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• 1. [Article] The fractal structure of surface water waves near breaking

  The goal of this research project is to determine the fractal nature, if any, which certain surface water waves exhibit when viewed on a microscopic scale. We make use of the mathematical formulation of ...

  Citation × Citation Citation Abstract Copy Title: The fractal structure of surface water waves near breaking Author: Munzenmayer, Katja The goal of this research project is to determine the fractal nature, if any, which certain surface water waves exhibit when viewed on a microscopic scale. We make use of the mathematical formulation of non-viscous fluids describing their physical properties. Using these expressions and including boundary conditions for free surfaces as well as taking the surface tension into consideration, we obtain a partial differential equation describing the dynamics of surface water waves. A brief introduction to the study of fractal geometry with several examples of well-known fractals is included. An important property of fractals is their non-integral dimension. Several methods of determining the dimension of a curve are described in this paper. Our wave equation is examined under different assumptions representing the conditions of a surface water wave near its breaking point. Solutions are developed using analytical and numerical methods. We determine the dimension of 'rough' solutions using one of the methods introduced and conclude that under certain conditions, surface water waves near their breaking point exhibit a fractal structure on a microscopic scale. Title: The fractal structure of surface water waves near breaking Author: Munzenmayer, Katja The goal of this research project is to determine the fractal nature, if any, which certain surface water waves exhibit when viewed on a microscopic scale. We make use of the mathematical formulation of non-viscous fluids describing their physical properties. Using these expressions and including boundary conditions for free surfaces as well as taking the surface tension into consideration, we obtain a partial differential equation describing the dynamics of surface water waves. A brief introduction to the study of fractal geometry with several examples of well-known fractals is included. An important property of fractals is their non-integral dimension. Several methods of determining the dimension of a curve are described in this paper. Our wave equation is examined under different assumptions representing the conditions of a surface water wave near its breaking point. Solutions are developed using analytical and numerical methods. We determine the dimension of 'rough' solutions using one of the methods introduced and conclude that under certain conditions, surface water waves near their breaking point exhibit a fractal structure on a microscopic scale. Close

• 2. [Article] Hydrologic connectivity constrains partitioning of global terrestrial water fluxes

  This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in the journal Science on 10 July 2015, ...

  Citation × Citation Citation Abstract Copy Title: Hydrologic connectivity constrains partitioning of global terrestrial water fluxes Author: Noone, David, Bowen, Gabriel, Good, Stephen P. This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in the journal Science on 10 July 2015, Volume 349 number 6244, DOI:10.1126/science.aaa5931. The published article is copyrighted by the American Association for the Advancement of Science and can be found at: http://www.sciencemag.org/journals/ Title: Hydrologic connectivity constrains partitioning of global terrestrial water fluxes Author: Noone, David, Bowen, Gabriel, Good, Stephen P. This is the author’s version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in the journal Science on 10 July 2015, Volume 349 number 6244, DOI:10.1126/science.aaa5931. The published article is copyrighted by the American Association for the Advancement of Science and can be found at: http://www.sciencemag.org/journals/ Close

• 3. [Article] Toxic Pollutants Measured in Surface Water and Fish Collected from the Willamette River Basin by the Oregon Department of Environmental Quality (2008 – 2010)

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Toxic Pollutants Measured in Surface Water and Fish Collected from the Willamette River Basin by the Oregon Department of Environmental Quality (2008 – 2010) Author: Hamel, Allen, Coyle, Jim, Johnson, Ben Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Toxic Pollutants Measured in Surface Water and Fish Collected from the Willamette River Basin by the Oregon Department of Environmental Quality (2008 – 2010) Author: Hamel, Allen, Coyle, Jim, Johnson, Ben Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 4. [Article] Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment, and cultured oysters in the Chesapeake Bay, MD, USA

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersi...

  Citation × Citation Citation Abstract Copy Title: Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment, and cultured oysters in the Chesapeake Bay, MD, USA Author: Jacobs, John M., Shaw, Kristi S., Crump, Byron C. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/microbiology. Title: Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment, and cultured oysters in the Chesapeake Bay, MD, USA Author: Jacobs, John M., Shaw, Kristi S., Crump, Byron C. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Frontiers Research Foundation. The published article can be found at: http://www.frontiersin.org/microbiology. Close

• 5. [Article] Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin

  Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on ...

  Citation × Citation Citation Abstract Copy Title: Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin Author: Abdallah, Mohamed (Mohamed Ahmed B.) Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on vegetation and how changes in surface-soil water affect plant water uptake. Studies in arid environments have evaluated the effect of groundwater variation and simulated precipitation on plant production and vegetation condition but it is not clear if plants respond equally to the availability of surface water or groundwater. This study was conducted in a greenhouse to evaluate growth and physiology of three desert graminoids (Distichlis spicata, Leymus triticoides, and Juncus arcticus) as affected by surface water availability (mimicking precipitation) or subsurface water availability (mimicking groundwater). The species of study are amply distributed in wetlands and open rangelands of western USA and were collected from two sources of ecological distribution: an area near Bishop, California, and an area near Burns, Oregon. The Bishop, California area has a characteristic shallow aquifer and plants in this area are considered somewhat dependent on groundwater. The Burns, Oregon, area sustains the same species but in a variety of soil moisture conditions. We had two general hypotheses for this study: 1) that the use of surface water is favored over groundwater and 2) that there are ecotypic differences in the response of the species to water availability. The first hypothesis was partially supported by the results of the study, but variability existed among species. However, when all species had equal access to both surface soil water and groundwater plants tended to preferentially use surface water. The second hypothesis was clearly supported by our results. Although the mechanism is not clear, it is possible that an area with periodic and predictable shallow groundwater underlying a dry or saline soil layer, such as the California site, might favor plant ecotypes with high proficiency in water acquisition by deeper roots. Knowledge of water use characteristics of vegetation is essential to provide management guidelines for areas where plants depend on both surface-soil water and groundwater. This study contributed to that knowledge. Further studies on ecotypic variation and an expansion to different species that inhabit areas with shallow aquifers are recommended. Title: Physiological impacts of groundwater and surface water application on desert graminoids of different geographic origin Author: Abdallah, Mohamed (Mohamed Ahmed B.) Desert plant communities are among the most sensitive to changes in soil water conditions. In areas with shallow aquifers, it is important to understand both the effects of groundwater alterations on vegetation and how changes in surface-soil water affect plant water uptake. Studies in arid environments have evaluated the effect of groundwater variation and simulated precipitation on plant production and vegetation condition but it is not clear if plants respond equally to the availability of surface water or groundwater. This study was conducted in a greenhouse to evaluate growth and physiology of three desert graminoids (Distichlis spicata, Leymus triticoides, and Juncus arcticus) as affected by surface water availability (mimicking precipitation) or subsurface water availability (mimicking groundwater). The species of study are amply distributed in wetlands and open rangelands of western USA and were collected from two sources of ecological distribution: an area near Bishop, California, and an area near Burns, Oregon. The Bishop, California area has a characteristic shallow aquifer and plants in this area are considered somewhat dependent on groundwater. The Burns, Oregon, area sustains the same species but in a variety of soil moisture conditions. We had two general hypotheses for this study: 1) that the use of surface water is favored over groundwater and 2) that there are ecotypic differences in the response of the species to water availability. The first hypothesis was partially supported by the results of the study, but variability existed among species. However, when all species had equal access to both surface soil water and groundwater plants tended to preferentially use surface water. The second hypothesis was clearly supported by our results. Although the mechanism is not clear, it is possible that an area with periodic and predictable shallow groundwater underlying a dry or saline soil layer, such as the California site, might favor plant ecotypes with high proficiency in water acquisition by deeper roots. Knowledge of water use characteristics of vegetation is essential to provide management guidelines for areas where plants depend on both surface-soil water and groundwater. This study contributed to that knowledge. Further studies on ecotypic variation and an expansion to different species that inhabit areas with shallow aquifers are recommended. Close

• 6. [Article] Oxygen isotope ratio, barium and salinity in waters around the North American coast from the Pacific to the Atlantic: Implications for freshwater sources to the Arctic throughflow

  In 2002, oxygen isotope ratios of water (H2 18O/H2 16O), dissolved barium, and salinity were measured in surface waters around northern North America to identify freshwater sources and to provide a large-scale ...

  Citation × Citation Citation Abstract Copy Title: Oxygen isotope ratio, barium and salinity in waters around the North American coast from the Pacific to the Atlantic: Implications for freshwater sources to the Arctic throughflow Author: McLaughlin, Fiona A., Carmack, Eddy C., Yamamoto-Kawai, Michiyo, Falkner, Kelly K. In 2002, oxygen isotope ratios of water (H2 18O/H2 16O), dissolved barium, and salinity were measured in surface waters around northern North America to identify freshwater sources and to provide a large-scale background for interpretation of regional inputs and processes. Oxygen isotope ratios showed that precipitation, river runoff, and sea ice meltwater were all significant contributors to the freshwater carried by the coastal component of the Arctic throughflow. Precipitation and runoff contributed 40% and 60%, respectively, to the freshwater found in surface waters along the Pacific coast. Sea ice meltwater contributed up to 65% to waters residing near the Mackenzie River and in the Canadian Arctic Archipelago. The salinity-barium relationship, after being corrected for dilution by sea ice meltwater, indicated that freshwater from the Mackenzie River flowed eastward into Amundsen Gulf. It did not, however, continue eastward through Dolphin Union Strait and Coronation Gulf in 2002. In the eastern part of the Canadian Arctic Archipelago, Baffin Bay and the Labrador Sea, barium concentrations in surface waters were low, the result of biological activity and/or local freshwater inputs with low barium concentrations. Title: Oxygen isotope ratio, barium and salinity in waters around the North American coast from the Pacific to the Atlantic: Implications for freshwater sources to the Arctic throughflow Author: McLaughlin, Fiona A., Carmack, Eddy C., Yamamoto-Kawai, Michiyo, Falkner, Kelly K. In 2002, oxygen isotope ratios of water (H2 18O/H2 16O), dissolved barium, and salinity were measured in surface waters around northern North America to identify freshwater sources and to provide a large-scale background for interpretation of regional inputs and processes. Oxygen isotope ratios showed that precipitation, river runoff, and sea ice meltwater were all significant contributors to the freshwater carried by the coastal component of the Arctic throughflow. Precipitation and runoff contributed 40% and 60%, respectively, to the freshwater found in surface waters along the Pacific coast. Sea ice meltwater contributed up to 65% to waters residing near the Mackenzie River and in the Canadian Arctic Archipelago. The salinity-barium relationship, after being corrected for dilution by sea ice meltwater, indicated that freshwater from the Mackenzie River flowed eastward into Amundsen Gulf. It did not, however, continue eastward through Dolphin Union Strait and Coronation Gulf in 2002. In the eastern part of the Canadian Arctic Archipelago, Baffin Bay and the Labrador Sea, barium concentrations in surface waters were low, the result of biological activity and/or local freshwater inputs with low barium concentrations. Close

• 7. [Article] Sub-regional detention siting : a methodology using GIS

  The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s ...

  Citation × Citation Citation Abstract Copy Title: Sub-regional detention siting : a methodology using GIS Author: Murdock, Carol L. The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s and has recently accelerated. A landscape level analysis of the urbanization process was combined with the results of a recently completed storm water master plan for the area. The project resulted in the identification of potential locations for combined detention and water quality facilities. It also served to further justify the recent revision of surface water management rules and regulations to include requirements for lower release rates from detention facilities and riparian and wetland buffers. Geographic Information Systems (GIS) was used extensively throughout the project to provide data input into the XPSWMM model that was used to analyze storm water flows and to identify infrastructure needs and requirements. In addition, GIS played a pivotal role in identifying factors which may be contributing to changes in stream condition in the basin. The results of this analysis project will be used by surface water managers in their continuing effort to refine current surface water management rules and regulations in the face of on-going development and continued urbanization. Title: Sub-regional detention siting : a methodology using GIS Author: Murdock, Carol L. The Mt. Scott watershed in northern Clackamas County, Oregon is an urban watershed that lies inside the Portland metropolitan urban growth boundary. Urbanization of the watershed began in the early 1970s and has recently accelerated. A landscape level analysis of the urbanization process was combined with the results of a recently completed storm water master plan for the area. The project resulted in the identification of potential locations for combined detention and water quality facilities. It also served to further justify the recent revision of surface water management rules and regulations to include requirements for lower release rates from detention facilities and riparian and wetland buffers. Geographic Information Systems (GIS) was used extensively throughout the project to provide data input into the XPSWMM model that was used to analyze storm water flows and to identify infrastructure needs and requirements. In addition, GIS played a pivotal role in identifying factors which may be contributing to changes in stream condition in the basin. The results of this analysis project will be used by surface water managers in their continuing effort to refine current surface water management rules and regulations in the face of on-going development and continued urbanization. Close

• 8. [Article] The effects of land use on mineral flat wetland hydrologic processes in lowland agricultural catchments

  Hydrologic processes within mineral flat wetlands, along with their connections to groundwater and downstream surface water in lowland agricultural catchments are poorly understood, particularly under ...

  Citation × Citation Citation Abstract Copy Title: The effects of land use on mineral flat wetland hydrologic processes in lowland agricultural catchments Author: Marshall, Sarah M. (Sarah Marie) Hydrologic processes within mineral flat wetlands, along with their connections to groundwater and downstream surface water in lowland agricultural catchments are poorly understood, particularly under different land uses. In the three field studies included in this thesis, we examined infiltration, wetland hydroperiod, groundwater recharge dynamics, surface runoff generation, and water quality in mineral flat wetlands using a combination of soil and hydrometric measurements, stable isotope tracers, and water chemistry analysis. Our overarching objectives were to examine, for mineral flat wetlands under native prairie, farmed grassland, and restored prairie land cover: 1) how different land management influences infiltration and wetland hydroperiod at the plot scale, 2) the effects of land use on seasonal groundwater-surface water dynamics at the field scale, and 3) seasonal variation in runoff sources and nutrient transport from native prairie and farmed wetlands at the small catchment scale. At the plot scale, our results suggest that edaphic factors, particularly those related to soil structure, are strongly associated with wetland infiltration and overall hydroperiod across least-altered prairie, farmed, and restored prairie mineral flat wetlands. The hydroperiod metrics we examined were generally more sensitive to level of site disturbance than land use alone. At the field scale, our results indicate that, in spite of land use differences and slight variations in soil stratigraphy, many similarities exist in overall wetland hydroperiod, water sources and evaporation rates for mineral flat wetlands in the Willamette Valley lowlands. Isotopic evidence suggests that the greatest degree of groundwater-surface water mixing occurs in the upper 0.5 m of the saturated soil profile across sites under all land uses. Finally, at the small catchment scale, farmed wetland runoff was isotopically similar to field surface water for most of the wet season, indicating that saturation excess was an important runoff generation process. Prairie wetland runoff was isotopically similar to upstream water throughout the winter, and briefly similar to shallow groundwater and surface water within the wetland in mid-spring. Throughout the wet season, elevated nitrate, sulfate, and chloride concentrations were observed in groundwater and surface water at the farm site, and deeper groundwater at the prairie site. Upstream-downstream runoff chemistry remained similar throughout the wet season at the prairie site. Farm site runoff chemistry reflected the dominant water source within the farm field throughout the wet season. Our findings suggest that, while surface water pathways dominate runoff from wetland flats under farm land use, large wetland flat fields have a high potential to absorb, store, and process nutrients and agrochemicals from on-site and nearby off-site chemical inputs. Mineral flats that maintain wetland hydrology in spite of farm use represent a unique balance between agricultural production and preservation of some of the water storage and delay, and water quality-related ecosystem services once provided at a much larger scale in the Willamette Valley lowlands. We anticipate that results of this work will lead to better understanding of key site-scale edaphic and hydrologic factors to consider when prioritizing and managing sites for restoration, and how site disturbance under a variety of land uses may impact different hydrologic processes and components of the wetland hydroperiod. Additionally, our results provide a better understanding of how land use affects seasonal runoff generation processes in mineral flat wetlands, and the water quality implications of modifying groundwater and surface water connectivity between mineral flats and surrounding surface drainage networks. Title: The effects of land use on mineral flat wetland hydrologic processes in lowland agricultural catchments Author: Marshall, Sarah M. (Sarah Marie) Hydrologic processes within mineral flat wetlands, along with their connections to groundwater and downstream surface water in lowland agricultural catchments are poorly understood, particularly under different land uses. In the three field studies included in this thesis, we examined infiltration, wetland hydroperiod, groundwater recharge dynamics, surface runoff generation, and water quality in mineral flat wetlands using a combination of soil and hydrometric measurements, stable isotope tracers, and water chemistry analysis. Our overarching objectives were to examine, for mineral flat wetlands under native prairie, farmed grassland, and restored prairie land cover: 1) how different land management influences infiltration and wetland hydroperiod at the plot scale, 2) the effects of land use on seasonal groundwater-surface water dynamics at the field scale, and 3) seasonal variation in runoff sources and nutrient transport from native prairie and farmed wetlands at the small catchment scale. At the plot scale, our results suggest that edaphic factors, particularly those related to soil structure, are strongly associated with wetland infiltration and overall hydroperiod across least-altered prairie, farmed, and restored prairie mineral flat wetlands. The hydroperiod metrics we examined were generally more sensitive to level of site disturbance than land use alone. At the field scale, our results indicate that, in spite of land use differences and slight variations in soil stratigraphy, many similarities exist in overall wetland hydroperiod, water sources and evaporation rates for mineral flat wetlands in the Willamette Valley lowlands. Isotopic evidence suggests that the greatest degree of groundwater-surface water mixing occurs in the upper 0.5 m of the saturated soil profile across sites under all land uses. Finally, at the small catchment scale, farmed wetland runoff was isotopically similar to field surface water for most of the wet season, indicating that saturation excess was an important runoff generation process. Prairie wetland runoff was isotopically similar to upstream water throughout the winter, and briefly similar to shallow groundwater and surface water within the wetland in mid-spring. Throughout the wet season, elevated nitrate, sulfate, and chloride concentrations were observed in groundwater and surface water at the farm site, and deeper groundwater at the prairie site. Upstream-downstream runoff chemistry remained similar throughout the wet season at the prairie site. Farm site runoff chemistry reflected the dominant water source within the farm field throughout the wet season. Our findings suggest that, while surface water pathways dominate runoff from wetland flats under farm land use, large wetland flat fields have a high potential to absorb, store, and process nutrients and agrochemicals from on-site and nearby off-site chemical inputs. Mineral flats that maintain wetland hydrology in spite of farm use represent a unique balance between agricultural production and preservation of some of the water storage and delay, and water quality-related ecosystem services once provided at a much larger scale in the Willamette Valley lowlands. We anticipate that results of this work will lead to better understanding of key site-scale edaphic and hydrologic factors to consider when prioritizing and managing sites for restoration, and how site disturbance under a variety of land uses may impact different hydrologic processes and components of the wetland hydroperiod. Additionally, our results provide a better understanding of how land use affects seasonal runoff generation processes in mineral flat wetlands, and the water quality implications of modifying groundwater and surface water connectivity between mineral flats and surrounding surface drainage networks. Close

• 9. [Article] What Lies Below: Options to Improve Sustainable Management of U.S./Mexico TransboundaryAquifers

  Globally, as surface water quality and quantity diminishes there is increasing reliance on groundwater to buffer water demands of growing populations. Today in many arid regions around the world aquifer ...

  Citation × Citation Citation Abstract Copy Title: What Lies Below: Options to Improve Sustainable Management of U.S./Mexico TransboundaryAquifers Author: Welch, Christina, N. Globally, as surface water quality and quantity diminishes there is increasing reliance on groundwater to buffer water demands of growing populations. Today in many arid regions around the world aquifer pumping rates far exceed recharge rates. Often the groundwater is nonrenewable, or thousands of years old. Despite the known hydrologic connection between surface and groundwater, existing institutions and laws governing surface water are poorly equipped to manage groundwater. While there are more than 600 international treaties governing surface water, only one treaty worldwide explicitly addresses groundwater allocation. Like many other regions of the world, the treaties covering the Paseo del Norte region shared between Mexico and the United States allocate the quantity and timing of surface water deliveries, yet fail to regulate groundwater abstraction. The three transboundary aquifers shared by two countries and three states (New Mexico/U.S., Texas/U.S., and Chihuahua/MX) within Paseo del Norte study area present an ideal microcosm to closer examine water management institutions across the local, state, national, and international scales. This research assesses the United States and Mexico’s institutional capacity to manage groundwater across each scale. The problem is imminent since the Hueco Bolson transboundary aquifer is the primary source of drinking water for nearly 2 million people and the fresh water is predicted to be completely depleted between 2020-2050. The ultimate objective is to identify which future legal, scientific and economic options can best contribute to more sustainable management of transboundary aquifers without compromising water security in both countries. This research proposes three major paths to move forward: the first step is to increase public awareness of the aquifer exploitation problem; second, for water managers to accurately plan for future water demands there should be a binational groundwater model built by scientists on both sides of the border; third, an international treaty or regional joint agreement is necessary to legally support groundwater management efforts. Title: What Lies Below: Options to Improve Sustainable Management of U.S./Mexico TransboundaryAquifers Author: Welch, Christina, N. Globally, as surface water quality and quantity diminishes there is increasing reliance on groundwater to buffer water demands of growing populations. Today in many arid regions around the world aquifer pumping rates far exceed recharge rates. Often the groundwater is nonrenewable, or thousands of years old. Despite the known hydrologic connection between surface and groundwater, existing institutions and laws governing surface water are poorly equipped to manage groundwater. While there are more than 600 international treaties governing surface water, only one treaty worldwide explicitly addresses groundwater allocation. Like many other regions of the world, the treaties covering the Paseo del Norte region shared between Mexico and the United States allocate the quantity and timing of surface water deliveries, yet fail to regulate groundwater abstraction. The three transboundary aquifers shared by two countries and three states (New Mexico/U.S., Texas/U.S., and Chihuahua/MX) within Paseo del Norte study area present an ideal microcosm to closer examine water management institutions across the local, state, national, and international scales. This research assesses the United States and Mexico’s institutional capacity to manage groundwater across each scale. The problem is imminent since the Hueco Bolson transboundary aquifer is the primary source of drinking water for nearly 2 million people and the fresh water is predicted to be completely depleted between 2020-2050. The ultimate objective is to identify which future legal, scientific and economic options can best contribute to more sustainable management of transboundary aquifers without compromising water security in both countries. This research proposes three major paths to move forward: the first step is to increase public awareness of the aquifer exploitation problem; second, for water managers to accurately plan for future water demands there should be a binational groundwater model built by scientists on both sides of the border; third, an international treaty or regional joint agreement is necessary to legally support groundwater management efforts. Close

• 10. [Article] Economic criteria as normative content in Oregon surface water law

  Citation × Citation Citation Abstract Copy Title: Economic criteria as normative content in Oregon surface water law Author: Whittaker, Gerald W. Title: Economic criteria as normative content in Oregon surface water law Author: Whittaker, Gerald W. Close

• 11. [Article] Effect of iron limitation on the cadmium to phosphorus ratio of natural phytoplankton assemblages from the Southern Ocean

  There is considerable interest in the biogeochemical cycling of cadmium (Cd) and phosphate (PO4) in surface waters, driven in part by the ongoing development of a paleonutrient proxy that utilizes Cd preserved ...

  Citation × Citation Citation Abstract Copy Title: Effect of iron limitation on the cadmium to phosphorus ratio of natural phytoplankton assemblages from the Southern Ocean Author: Fitzwater, Steve E., Cullen, Jay T., Sherrell, Robert M., Chase, Zanna, Coale, Kenneth H. There is considerable interest in the biogeochemical cycling of cadmium (Cd) and phosphate (PO4) in surface waters, driven in part by the ongoing development of a paleonutrient proxy that utilizes Cd preserved in fossil planktonic foraminifera to determine past PO4 utilization efficiencies in ocean surface waters. The present article reports the results of a field study into the effects of Fe limitation on the Cd : P composition of natural assemblages of marine phytoplankton in the Antarctic Zone of the Pacific sector of the Southern Ocean. Iron enrichment to shipboard incubation bottles led to increases in community growth rate and final biomass. After 10.7 d of incubation, the climax community was dominated by large diatoms of the genus Fragillariopsis, Pseudonitzschia, and Nitzschia. Direct measurements of phytoplankton metal : P ratios from controlled shipboard experiments indicate that Cd : P, Co: P, and Zn : P ratios decreased from control values with increasing initial dissolved Fe concentrations in the incubation bottles, by factors of ~2–10 at highest Fe additions. We suggest that the effect of Fe limitation on resident diatoms is to decrease growth rate, leading to elevated cellular Cd content. The dissolved Cd : P ratio in iron-limited surface waters of the Southern Ocean may, therefore, respond to the supply of Fe to the resident phytoplankton community, which has implications for the developing paleonutrient proxy. We suggest that the biological uptake of Cd and P is independent of the dissolved Cd: PO4 ratio. As a consequence, the results argue against the use of empirical Rayleigh fractionation models or models with fixed phytoplankton uptake ratios to account for regional variability in surface water dissolved Cd : PO4. Title: Effect of iron limitation on the cadmium to phosphorus ratio of natural phytoplankton assemblages from the Southern Ocean Author: Fitzwater, Steve E., Cullen, Jay T., Sherrell, Robert M., Chase, Zanna, Coale, Kenneth H. There is considerable interest in the biogeochemical cycling of cadmium (Cd) and phosphate (PO4) in surface waters, driven in part by the ongoing development of a paleonutrient proxy that utilizes Cd preserved in fossil planktonic foraminifera to determine past PO4 utilization efficiencies in ocean surface waters. The present article reports the results of a field study into the effects of Fe limitation on the Cd : P composition of natural assemblages of marine phytoplankton in the Antarctic Zone of the Pacific sector of the Southern Ocean. Iron enrichment to shipboard incubation bottles led to increases in community growth rate and final biomass. After 10.7 d of incubation, the climax community was dominated by large diatoms of the genus Fragillariopsis, Pseudonitzschia, and Nitzschia. Direct measurements of phytoplankton metal : P ratios from controlled shipboard experiments indicate that Cd : P, Co: P, and Zn : P ratios decreased from control values with increasing initial dissolved Fe concentrations in the incubation bottles, by factors of ~2–10 at highest Fe additions. We suggest that the effect of Fe limitation on resident diatoms is to decrease growth rate, leading to elevated cellular Cd content. The dissolved Cd : P ratio in iron-limited surface waters of the Southern Ocean may, therefore, respond to the supply of Fe to the resident phytoplankton community, which has implications for the developing paleonutrient proxy. We suggest that the biological uptake of Cd and P is independent of the dissolved Cd: PO4 ratio. As a consequence, the results argue against the use of empirical Rayleigh fractionation models or models with fixed phytoplankton uptake ratios to account for regional variability in surface water dissolved Cd : PO4. Close

• 12. [Article] Surface-water contaminant routing using a digital stream information system

  Citation × Citation Citation Abstract Copy Title: Surface-water contaminant routing using a digital stream information system Author: Broad, Tyson Megee Title: Surface-water contaminant routing using a digital stream information system Author: Broad, Tyson Megee Close

• 13. [Article] A reconstruction of changes in land use/land cover in Vermont relative to sensitivity of surface waters to acidic deposition

  Citation × Citation Citation Abstract Copy Title: A reconstruction of changes in land use/land cover in Vermont relative to sensitivity of surface waters to acidic deposition Author: Clarke, Sharon Elaine Title: A reconstruction of changes in land use/land cover in Vermont relative to sensitivity of surface waters to acidic deposition Author: Clarke, Sharon Elaine Close

• 14. [Article] A study of carbon dioxide partial pressures in surface waters of the Pacific Ocean

  Citation × Citation Citation Abstract Copy Title: A study of carbon dioxide partial pressures in surface waters of the Pacific Ocean Author: Gordon, Louis Irwin, 1928- Title: A study of carbon dioxide partial pressures in surface waters of the Pacific Ocean Author: Gordon, Louis Irwin, 1928- Close

• 15. [Article] Biomarker temperature estimates for modern and last glacial surface waters of the California Current system between 33° and 42° N

  Citation × Citation Citation Abstract Copy Title: Biomarker temperature estimates for modern and last glacial surface waters of the California Current system between 33° and 42° N Author: Doose, Heidi, Lyle, Mitch W., Prahl, Fredrick Title: Biomarker temperature estimates for modern and last glacial surface waters of the California Current system between 33° and 42° N Author: Doose, Heidi, Lyle, Mitch W., Prahl, Fredrick Close

• 16. [Article] The development of a hydrological model of the Walla Walla Basin using Integrated Water Flow Model

  The Walla Walla basin lies in an arid region of Eastern Washington and Oregon. A large portion of the area is devoted to agricultural production, relying on irrigation water diverted from the Walla Walla ...

  Citation × Citation Citation Abstract Copy Title: The development of a hydrological model of the Walla Walla Basin using Integrated Water Flow Model Author: Scherberg, Jacob N. The Walla Walla basin lies in an arid region of Eastern Washington and Oregon. A large portion of the area is devoted to agricultural production, relying on irrigation water diverted from the Walla Walla River and underlying aquifers occurring within Quaternary and Mio-pliocene era gravel deposits, as well as a supplemental source from the Columbia River Basalt formation. Heavy water demand over summer months has resulted in a fully allocated surface water supply and significant drawdown in groundwater levels. The Walla Walla River also hosts two salmonid species listed as threatened under the endangered species act and entitled to federal protection. Specific questions have emerged regarding regional water supply as stakeholders work towards management strategies that meet water user demands, well also addressing concerns such as groundwater depletion and fish habitat. Currently, there are proposals aimed at increasing water use efficiency such as the lining of permeable canal beds and the expansion of a shallow aquifer recharge program. Effective implementation of such strategies, in part, relies on understanding the interactions between surface water and groundwater within this region. This project used the distributed hydrologic model, Integrated Water Flow Model (IWFM), for simulating surface and subsurface flows over a portion of the Walla Walla River basin spanning from Milton Freewater, Oregon to west of Touchet, Washington. This application of IWFM uses a grid with an average spacing of 100 x 100 meters over the 230 square kilometer model area. The model was developed and calibrated using data from 2007 through 2009, with 2010 data to be used as a data set for validation. Data collection has been a collaborative effort between a research team from Oregon State University and the Walla Walla Basin Watershed Council (WWBWC). This thesis provides explanation and documentation of model development. This includes details of data collection and processing for groundwater and surface water conditions, estimation of initial and boundary conditions, parameter calibration, model validation, and error analysis. Data sources include federal and state agencies, a gauge network managed by the WWBWC, and geologic research primarily performed by Kevin Lindsey of GSI Water Solutions with support of the WWBWC. Parameters have been independently determined from field measurements whenever possible. Otherwise they were estimated using established methods of hydrologic analysis, values drawn from previous regional studies, or the process of model calibration. Outputs include detailed hydrological budgets and hydrographs for groundwater and surface water gauges. The calibrated model has an overall correlation coefficient of 0.59 for groundwater and 0.63 for surface water. The standard deviation for groundwater is 3.2 meters at 62 well locations and surface water has a mean relative error of 22.3 percent at 34 gauges. This model intended as a tool for formulating water budgets for the basin under present conditions and making predictions of systemic responses to hypothetical water management scenarios. Scenarios of increased inputs into the Locher Road aquifer recharge site and conversion of irrigation district canals into pipelines are presented. Title: The development of a hydrological model of the Walla Walla Basin using Integrated Water Flow Model Author: Scherberg, Jacob N. The Walla Walla basin lies in an arid region of Eastern Washington and Oregon. A large portion of the area is devoted to agricultural production, relying on irrigation water diverted from the Walla Walla River and underlying aquifers occurring within Quaternary and Mio-pliocene era gravel deposits, as well as a supplemental source from the Columbia River Basalt formation. Heavy water demand over summer months has resulted in a fully allocated surface water supply and significant drawdown in groundwater levels. The Walla Walla River also hosts two salmonid species listed as threatened under the endangered species act and entitled to federal protection. Specific questions have emerged regarding regional water supply as stakeholders work towards management strategies that meet water user demands, well also addressing concerns such as groundwater depletion and fish habitat. Currently, there are proposals aimed at increasing water use efficiency such as the lining of permeable canal beds and the expansion of a shallow aquifer recharge program. Effective implementation of such strategies, in part, relies on understanding the interactions between surface water and groundwater within this region. This project used the distributed hydrologic model, Integrated Water Flow Model (IWFM), for simulating surface and subsurface flows over a portion of the Walla Walla River basin spanning from Milton Freewater, Oregon to west of Touchet, Washington. This application of IWFM uses a grid with an average spacing of 100 x 100 meters over the 230 square kilometer model area. The model was developed and calibrated using data from 2007 through 2009, with 2010 data to be used as a data set for validation. Data collection has been a collaborative effort between a research team from Oregon State University and the Walla Walla Basin Watershed Council (WWBWC). This thesis provides explanation and documentation of model development. This includes details of data collection and processing for groundwater and surface water conditions, estimation of initial and boundary conditions, parameter calibration, model validation, and error analysis. Data sources include federal and state agencies, a gauge network managed by the WWBWC, and geologic research primarily performed by Kevin Lindsey of GSI Water Solutions with support of the WWBWC. Parameters have been independently determined from field measurements whenever possible. Otherwise they were estimated using established methods of hydrologic analysis, values drawn from previous regional studies, or the process of model calibration. Outputs include detailed hydrological budgets and hydrographs for groundwater and surface water gauges. The calibrated model has an overall correlation coefficient of 0.59 for groundwater and 0.63 for surface water. The standard deviation for groundwater is 3.2 meters at 62 well locations and surface water has a mean relative error of 22.3 percent at 34 gauges. This model intended as a tool for formulating water budgets for the basin under present conditions and making predictions of systemic responses to hypothetical water management scenarios. Scenarios of increased inputs into the Locher Road aquifer recharge site and conversion of irrigation district canals into pipelines are presented. Close

• 17. [Article] The Orange County Water District Riverbed Filtration Pilot Project: Solids and Organic Carbon Removal Using Induced Riverbed Infiltration

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: The Orange County Water District Riverbed Filtration Pilot Project: Solids and Organic Carbon Removal Using Induced Riverbed Infiltration Author: Rice, Robert, Hutchinson, Adam, Milczarek, Michael, Keller, Jason, Woodside, Greg Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: The Orange County Water District Riverbed Filtration Pilot Project: Solids and Organic Carbon Removal Using Induced Riverbed Infiltration Author: Rice, Robert, Hutchinson, Adam, Milczarek, Michael, Keller, Jason, Woodside, Greg Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 18. [Article] Irrigation water and plant density effects on the epidemiology of aerial stem rot of potatoes

  Field plots of cv. Russet Burbank potatoes from a single seedlot were established at four sites over two seasons (1985-86) in two locations in Oregon to determine the role of water-borne inoculum of Erwinia ...

  Citation × Citation Citation Abstract Copy Title: Irrigation water and plant density effects on the epidemiology of aerial stem rot of potatoes Author: Cappaert, Marlys R. Field plots of cv. Russet Burbank potatoes from a single seedlot were established at four sites over two seasons (1985-86) in two locations in Oregon to determine the role of water-borne inoculum of Erwinia carotovora in plant infection. One site at each location was irrigated from a surface-water source and the other from a well-water source. Prior to planting, seed tubers and field soil were assayed for presence of Erwinia spp.. Populations of soft rot erwinias in water and on leaf surfaces, and the incidence of aerial stem rot were determined bimonthly from plant emergence until two weeks prior to regional harvest. Strains recovered from all sources were characterized biochemically, and Erwinia carotovora subsp. carotovora strains were typed serologically by Ouchterlony agar double diffusion. Populations of soft rot erwinias were consistently higher in surface water compared to well water. Populations ranged from 0 to 524 and 0 to 25 cfu/ml in surface-water sources in 1985 and 1986, respectively. Detection of soft rot erwinias in well water usually required enrichment. Populations of soft rot erwinias on potato foliage were highest in midseason after row closure. Populations in plots irrigated with surface-water and well-water were similar and ranged from 0 to 5.90 log cfu/g and from 0 to 6.22 log cfu/g fresh weight in 1985 and 1986, respectively. Final proportion of stems with aerial stem rot was consistently higher in well-water irrigated sites ranging from a low of 0.09 in the surface-water irrigated site in 1985 to a high of 0.51 in the well-water irrigated site in 1986. Over 90% of strains recovered from all sources were characterized as E. c. subsp. carotovora. About 25% of the E. c. subsp. carotovora strains recovered from all sources were identified serologically. At all but two sites over two years some of the strains recovered from water sources were the same serologically as epiphytic strains and strains recovered from diseased stems. A majority of stains isolated from diseased stems differed serologically from water serogroups at all locations. Field plots of potato cv. Russet Burbank were established at four sites in two years to determine the effect of plant density and plant spacing on development of aerial stem rot. Plant densities were 13, 26, and 52 x 10³ plants per hectare. The intermediate density had two treatments with different within-row and between-row spacing arrangements. Treatment effects were measured by onset of disease symptoms, final proportion of disease and area under the disease progress curve (AUDPC). In 1986, leaf area index was measured and throughout both seasons leaf wetness was monitored with a CR21X Campbell Scientific micrologger. Onset of aerial stem rot symptoms occurred earlier and final proportion of disease and AUDPC were greater in dense compared to sparse plantings. Larger differences in onset of disease and AUDPC occurred with a decrease in between-row spacings than in a decrease in within-row spacings. A linear regression model that used area under the leaf area index curve (AULAIC) for the four plant spacings as the independent variables accounted for 89-98% of the variation in AUDPC. Highest leaf area index values and longest average duration of leaf wetness preceded highest level of disease by two weeks. Title: Irrigation water and plant density effects on the epidemiology of aerial stem rot of potatoes Author: Cappaert, Marlys R. Field plots of cv. Russet Burbank potatoes from a single seedlot were established at four sites over two seasons (1985-86) in two locations in Oregon to determine the role of water-borne inoculum of Erwinia carotovora in plant infection. One site at each location was irrigated from a surface-water source and the other from a well-water source. Prior to planting, seed tubers and field soil were assayed for presence of Erwinia spp.. Populations of soft rot erwinias in water and on leaf surfaces, and the incidence of aerial stem rot were determined bimonthly from plant emergence until two weeks prior to regional harvest. Strains recovered from all sources were characterized biochemically, and Erwinia carotovora subsp. carotovora strains were typed serologically by Ouchterlony agar double diffusion. Populations of soft rot erwinias were consistently higher in surface water compared to well water. Populations ranged from 0 to 524 and 0 to 25 cfu/ml in surface-water sources in 1985 and 1986, respectively. Detection of soft rot erwinias in well water usually required enrichment. Populations of soft rot erwinias on potato foliage were highest in midseason after row closure. Populations in plots irrigated with surface-water and well-water were similar and ranged from 0 to 5.90 log cfu/g and from 0 to 6.22 log cfu/g fresh weight in 1985 and 1986, respectively. Final proportion of stems with aerial stem rot was consistently higher in well-water irrigated sites ranging from a low of 0.09 in the surface-water irrigated site in 1985 to a high of 0.51 in the well-water irrigated site in 1986. Over 90% of strains recovered from all sources were characterized as E. c. subsp. carotovora. About 25% of the E. c. subsp. carotovora strains recovered from all sources were identified serologically. At all but two sites over two years some of the strains recovered from water sources were the same serologically as epiphytic strains and strains recovered from diseased stems. A majority of stains isolated from diseased stems differed serologically from water serogroups at all locations. Field plots of potato cv. Russet Burbank were established at four sites in two years to determine the effect of plant density and plant spacing on development of aerial stem rot. Plant densities were 13, 26, and 52 x 10³ plants per hectare. The intermediate density had two treatments with different within-row and between-row spacing arrangements. Treatment effects were measured by onset of disease symptoms, final proportion of disease and area under the disease progress curve (AUDPC). In 1986, leaf area index was measured and throughout both seasons leaf wetness was monitored with a CR21X Campbell Scientific micrologger. Onset of aerial stem rot symptoms occurred earlier and final proportion of disease and AUDPC were greater in dense compared to sparse plantings. Larger differences in onset of disease and AUDPC occurred with a decrease in between-row spacings than in a decrease in within-row spacings. A linear regression model that used area under the leaf area index curve (AULAIC) for the four plant spacings as the independent variables accounted for 89-98% of the variation in AUDPC. Highest leaf area index values and longest average duration of leaf wetness preceded highest level of disease by two weeks. Close

• 19. [Article] Numerical computation of free surface water flow

  The present thesis is a report of investigations on a model for computing the water flow in the wave tank of the OSU Wave Laboratory. A wave board, established at one end of the 100 m long, 4 m wide and ...

  Citation × Citation Citation Abstract Copy Title: Numerical computation of free surface water flow Author: Kuhnert, Jorg The present thesis is a report of investigations on a model for computing the water flow in the wave tank of the OSU Wave Laboratory. A wave board, established at one end of the 100 m long, 4 m wide and 6 m deep wave tank, produces water waves by periodically moving back and forth. The resulting free surface water flow will be modeled physically. This physical model will be transformed into a mathematical model which is implemented on a computer. The goal is to approximately compute the velocity distribution of the fluid modeled as a linear combination of basis functions. Certain well known mathematical tools such as the Galerkin method or the idea of finite elements are employed. The theoretical developments are done for the three-dimensional case. However, numerical experiments are performed in two dimensions only. Two different types of basis functions will be introduced and investigated. Their advantages, disadvantages and capability to compute realistic results will clearly be shown and demonstrated in practice. Several problems occured during the development of the computation algorithms. These problems are outlined in this thesis, and several solutions are suggested. For example, a method how to deal with rising and falling water surface at a vertical boundary will be presented. The results of five numerical test runs will be exhibited, underlining what the theory predicts. Title: Numerical computation of free surface water flow Author: Kuhnert, Jorg The present thesis is a report of investigations on a model for computing the water flow in the wave tank of the OSU Wave Laboratory. A wave board, established at one end of the 100 m long, 4 m wide and 6 m deep wave tank, produces water waves by periodically moving back and forth. The resulting free surface water flow will be modeled physically. This physical model will be transformed into a mathematical model which is implemented on a computer. The goal is to approximately compute the velocity distribution of the fluid modeled as a linear combination of basis functions. Certain well known mathematical tools such as the Galerkin method or the idea of finite elements are employed. The theoretical developments are done for the three-dimensional case. However, numerical experiments are performed in two dimensions only. Two different types of basis functions will be introduced and investigated. Their advantages, disadvantages and capability to compute realistic results will clearly be shown and demonstrated in practice. Several problems occured during the development of the computation algorithms. These problems are outlined in this thesis, and several solutions are suggested. For example, a method how to deal with rising and falling water surface at a vertical boundary will be presented. The results of five numerical test runs will be exhibited, underlining what the theory predicts. Close

• 20. [Article] Irrigation Decisions for Major West Coast Crops: Water Scarcity and Climatic Determinants

  Access to this item has been restricted by repository administrators at the request of the publisher, Oxford University Press, until June 15, 2017.

  Citation × Citation Citation Abstract Copy Title: Irrigation Decisions for Major West Coast Crops: Water Scarcity and Climatic Determinants Author: Olen, Beau, Wu, JunJie, Langpap, Christian Access to this item has been restricted by repository administrators at the request of the publisher, Oxford University Press, until June 15, 2017. Title: Irrigation Decisions for Major West Coast Crops: Water Scarcity and Climatic Determinants Author: Olen, Beau, Wu, JunJie, Langpap, Christian Access to this item has been restricted by repository administrators at the request of the publisher, Oxford University Press, until June 15, 2017. Close

• 21. [Article] Surface water variation and water storage potential in Upper Klamath Basin, 2000-2012

  Citation × Citation Citation Abstract Copy Title: Surface water variation and water storage potential in Upper Klamath Basin, 2000-2012 Author: Tanner, Andrew M. Title: Surface water variation and water storage potential in Upper Klamath Basin, 2000-2012 Author: Tanner, Andrew M. Close

• 22. [Article] Flume testing of underwater seep detection using temperature sensing on or just below the surface of sand or gravel sediments

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291944-7973.

  Citation × Citation Citation Abstract Copy Title: Flume testing of underwater seep detection using temperature sensing on or just below the surface of sand or gravel sediments Author: Selker, J. S., Selker, F. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291944-7973. Title: Flume testing of underwater seep detection using temperature sensing on or just below the surface of sand or gravel sediments Author: Selker, J. S., Selker, F. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291944-7973. Close

• 23. [Article] Iron, nutrient, and phytoplankton distributions in Oregon coastal waters

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Iron, nutrient, and phytoplankton distributions in Oregon coastal waters Author: Wheeler, Patricia A., Chase, Zanna, Marra, John, van Geen, Alexander, Kosro, P. Michael, 1951- Copyrighted by American Geophysical Union. Title: Iron, nutrient, and phytoplankton distributions in Oregon coastal waters Author: Wheeler, Patricia A., Chase, Zanna, Marra, John, van Geen, Alexander, Kosro, P. Michael, 1951- Copyrighted by American Geophysical Union. Close

• 24. [Article] Modeling surface water and groundwater interactions near Milton- Freewater, Oregon

  The gravel aquifer of the Oregon side of Walla Walla River Basin has a strong hydrologic connection to surface water through a series of springs, unlined irrigation canals, the Walla Walla River, numerous ...

  Citation × Citation Citation Abstract Copy Title: Modeling surface water and groundwater interactions near Milton- Freewater, Oregon Author: Petrides Jimenez, Aristides Crisostomos The gravel aquifer of the Oregon side of Walla Walla River Basin has a strong hydrologic connection to surface water through a series of springs, unlined irrigation canals, the Walla Walla River, numerous wells and, since 2004, artificial recharge to the shallow aquifer using infiltration basins. The finite element Integrated Water Flow Model (IWFM) developed by California Department of Water Resources was used to quantify all of the major hydrologic features of the basin. Using the information provided by the Walla Walla Basin Watershed Council, irrigation districts, and previous studies conducted at Oregon State University and by consultants, the model was setup and calibrated, and a water budget simulation was performed for the years of 2003 to 2006. It is shown that close to 96 percent of the land use water demand goes to agriculture growing 16 major crops. 60 percent of the water comes from surface water diversions flowing through unlined irrigation canals , which themselves lose 28 percent of their inflow to the unconfined gravel aquifer. The calibrated and validated model was used to simulate the flow of the Johnson Creek Springs, which were shown to have increased flow due to the artificial recharge project. Title: Modeling surface water and groundwater interactions near Milton- Freewater, Oregon Author: Petrides Jimenez, Aristides Crisostomos The gravel aquifer of the Oregon side of Walla Walla River Basin has a strong hydrologic connection to surface water through a series of springs, unlined irrigation canals, the Walla Walla River, numerous wells and, since 2004, artificial recharge to the shallow aquifer using infiltration basins. The finite element Integrated Water Flow Model (IWFM) developed by California Department of Water Resources was used to quantify all of the major hydrologic features of the basin. Using the information provided by the Walla Walla Basin Watershed Council, irrigation districts, and previous studies conducted at Oregon State University and by consultants, the model was setup and calibrated, and a water budget simulation was performed for the years of 2003 to 2006. It is shown that close to 96 percent of the land use water demand goes to agriculture growing 16 major crops. 60 percent of the water comes from surface water diversions flowing through unlined irrigation canals , which themselves lose 28 percent of their inflow to the unconfined gravel aquifer. The calibrated and validated model was used to simulate the flow of the Johnson Creek Springs, which were shown to have increased flow due to the artificial recharge project. Close

• 25. [Article] Surface Water Interaction with “Confined” Columbia River Basalt Aquifers – Impacts to Streams from Declining Groundwater Levels near Mosier, Oregon

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Surface Water Interaction with “Confined” Columbia River Basalt Aquifers – Impacts to Streams from Declining Groundwater Levels near Mosier, Oregon Author: Lite Jr., Kenneth E. Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Surface Water Interaction with “Confined” Columbia River Basalt Aquifers – Impacts to Streams from Declining Groundwater Levels near Mosier, Oregon Author: Lite Jr., Kenneth E. Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 26. [Article] Satellite-based prediction of pCO₂ in coastal waters of the eastern North Pacific

  This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/progress-in-oceanography/. To the best of our knowledge, one or ...

  Citation × Citation Citation Abstract Copy Title: Satellite-based prediction of pCO₂ in coastal waters of the eastern North Pacific Author: Takahashi, Taro, Feely, Richard, Hales, Burke, Letelier, Ricardo, Sabine, Christopher, Strutton, Peter G., Chavez, Francisco, Saraceno, Martin This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/progress-in-oceanography/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Satellite-based prediction of pCO₂ in coastal waters of the eastern North Pacific Author: Takahashi, Taro, Feely, Richard, Hales, Burke, Letelier, Ricardo, Sabine, Christopher, Strutton, Peter G., Chavez, Francisco, Saraceno, Martin This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/progress-in-oceanography/. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 27. [Article] Observations of mixed layer restratification by onshore surface transport following wind reversal in a coastal upwelling region

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Observations of mixed layer restratification by onshore surface transport following wind reversal in a coastal upwelling region Author: Levine, Murray D., Austin, J. A., Dale, Andrew C., Barth, John A. copyrighted by American Geophysical Union Title: Observations of mixed layer restratification by onshore surface transport following wind reversal in a coastal upwelling region Author: Levine, Murray D., Austin, J. A., Dale, Andrew C., Barth, John A. copyrighted by American Geophysical Union Close

• 28. [Article] Recreational swimmers' exposure to Vibrio vulnificus and Vibrio parahaemolyticus in the Chesapeake Bay, Maryland, USA

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier ...

  Citation × Citation Citation Abstract Copy Title: Recreational swimmers' exposure to Vibrio vulnificus and Vibrio parahaemolyticus in the Chesapeake Bay, Maryland, USA Author: Jacobs, John M., Sapkota, Amy R., Shaw, Kristi S., He, Xin, Crump, Byron C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/environment-international. Title: Recreational swimmers' exposure to Vibrio vulnificus and Vibrio parahaemolyticus in the Chesapeake Bay, Maryland, USA Author: Jacobs, John M., Sapkota, Amy R., Shaw, Kristi S., He, Xin, Crump, Byron C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/environment-international. Close

• 29. [Article] Improved HF183 Quantitative Real-Time PCR Assay for Characterization of Human Fecal Pollution in Ambient Surface Water Samples

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the American ...

  Citation × Citation Citation Abstract Copy Title: Improved HF183 Quantitative Real-Time PCR Assay for Characterization of Human Fecal Pollution in Ambient Surface Water Samples Author: Borchardt, Mark A., Field, Katharine G., Varma, Manju, Knight, R., Haugland, Richard A., Millen, Hana T., Shanks, Orin C., Green, Hyatt C., Sivaganesan, Mano, Kelty, Catherine A., Walters, William A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the American Society for Microbiology and can be found at: http://aem.asm.org/. Title: Improved HF183 Quantitative Real-Time PCR Assay for Characterization of Human Fecal Pollution in Ambient Surface Water Samples Author: Borchardt, Mark A., Field, Katharine G., Varma, Manju, Knight, R., Haugland, Richard A., Millen, Hana T., Shanks, Orin C., Green, Hyatt C., Sivaganesan, Mano, Kelty, Catherine A., Walters, William A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the American Society for Microbiology and can be found at: http://aem.asm.org/. Close

• 30. [Article] Mixing of chlorophyll from the Middle Atlantic Bight cold pool into the Gulf Stream at Cape Hatteras in July 1993

  In July 1993 we collected hydrographic data and information on chlorophyll distribution on the continental shelf north of Cape Hatteras and across the shelf break at Cape Hatteras. The data show that a ...

  Citation × Citation Citation Abstract Copy Title: Mixing of chlorophyll from the Middle Atlantic Bight cold pool into the Gulf Stream at Cape Hatteras in July 1993 Author: Huyer, Adriana, 1945-, Sherry, Nelson D., Wood, A. Michelle In July 1993 we collected hydrographic data and information on chlorophyll distribution on the continental shelf north of Cape Hatteras and across the shelf break at Cape Hatteras. The data show that a warm, transparent mixed layer lies over much colder, euphotic, chlorophyll-rich bottom water on the shelf. This layer has temperature and salinity properties characteristic of the Middle Atlantic Bight (MAB) cold pool, a distinctive mass of cold bottom water formed when cold water from the Gulf of Maine and Scotian Shelf is isolated from surface water by vernal warming and seasonal stratification [Houghton et al., 1982]. The constant density of this chlorophyll-rich water (σФ = 25.0–25.6) combined with a strong chlorophyll gradient along the 25 σФ isopycnal at the shelf break indicates that chlorophyll advected off the shelf at Cape Hatteras in July 1993. TS diagrams further indicate that cold pool water, and the chlorophyll it contained, mixed into upper levels of the Gulf Stream. Thus the MAB may contribute to the nutrient budget of Atlantic surface waters through a long loop of circulation that transports deep water from the Labrador Sea to Cape Hatteras. Title: Mixing of chlorophyll from the Middle Atlantic Bight cold pool into the Gulf Stream at Cape Hatteras in July 1993 Author: Huyer, Adriana, 1945-, Sherry, Nelson D., Wood, A. Michelle In July 1993 we collected hydrographic data and information on chlorophyll distribution on the continental shelf north of Cape Hatteras and across the shelf break at Cape Hatteras. The data show that a warm, transparent mixed layer lies over much colder, euphotic, chlorophyll-rich bottom water on the shelf. This layer has temperature and salinity properties characteristic of the Middle Atlantic Bight (MAB) cold pool, a distinctive mass of cold bottom water formed when cold water from the Gulf of Maine and Scotian Shelf is isolated from surface water by vernal warming and seasonal stratification [Houghton et al., 1982]. The constant density of this chlorophyll-rich water (σФ = 25.0–25.6) combined with a strong chlorophyll gradient along the 25 σФ isopycnal at the shelf break indicates that chlorophyll advected off the shelf at Cape Hatteras in July 1993. TS diagrams further indicate that cold pool water, and the chlorophyll it contained, mixed into upper levels of the Gulf Stream. Thus the MAB may contribute to the nutrient budget of Atlantic surface waters through a long loop of circulation that transports deep water from the Labrador Sea to Cape Hatteras. Close

• 31. [Article] Fate of ammonia volatilized from a confinement livestock facility

  A conceptual model was developed to further the understanding of the evolution and fate of volatilized ammonia in the atmosphere. Recent trends in livestock rearing have been toward confinement facilities ...

  Citation × Citation Citation Abstract Copy Title: Fate of ammonia volatilized from a confinement livestock facility Author: Hoffman, Eldon Randall A conceptual model was developed to further the understanding of the evolution and fate of volatilized ammonia in the atmosphere. Recent trends in livestock rearing have been toward confinement facilities in which high animal concentrations are maintained. One of the impacts of these facilities has been increased local concentrations of ammonia in the atmosphere-directly resulting from surface volatilization associated with the facility. The various components of the model serve as sinks for the atmospheric ammonia and subsequently, under the right conditions, will also emit ammonia. Depending upon the degree of influence which each component will display, atmospheric ammonia can become a serious pollutant. The most significant of these potential pollution situations is the eutrophication of surface waters resulting from the direct absorption of atmospheric ammonia. Ammonia evolution is also related to odor emission which is a major social concern relative to livestock production. A knowledge of the system described by the model and the interaction of the system components serve as the basis in developing a pollution management philosophy. The environmental impact of a livestock facility upon surface water bodies can be predicted by estimating the potential ammonia absorption rate, and the impact can be lessened by modifying the other system components. This approach takes advantage of nature's assimulative capacity. Title: Fate of ammonia volatilized from a confinement livestock facility Author: Hoffman, Eldon Randall A conceptual model was developed to further the understanding of the evolution and fate of volatilized ammonia in the atmosphere. Recent trends in livestock rearing have been toward confinement facilities in which high animal concentrations are maintained. One of the impacts of these facilities has been increased local concentrations of ammonia in the atmosphere-directly resulting from surface volatilization associated with the facility. The various components of the model serve as sinks for the atmospheric ammonia and subsequently, under the right conditions, will also emit ammonia. Depending upon the degree of influence which each component will display, atmospheric ammonia can become a serious pollutant. The most significant of these potential pollution situations is the eutrophication of surface waters resulting from the direct absorption of atmospheric ammonia. Ammonia evolution is also related to odor emission which is a major social concern relative to livestock production. A knowledge of the system described by the model and the interaction of the system components serve as the basis in developing a pollution management philosophy. The environmental impact of a livestock facility upon surface water bodies can be predicted by estimating the potential ammonia absorption rate, and the impact can be lessened by modifying the other system components. This approach takes advantage of nature's assimulative capacity. Close

• 32. [Article] Distribution of membrane lipids of planktonic Crenarchaeota in the Arabian Sea

  Intact core tetraether membrane lipids of marine planktonic Crenarchaeota were quantified in water column-suspended particulate matter obtained from four depth intervals (~70, 500, 1,000 and 1,500 m) at ...

  Citation × Citation Citation Abstract Copy Title: Distribution of membrane lipids of planktonic Crenarchaeota in the Arabian Sea Author: Wakeham, Stuart G., Hopmans, Ellen C., Sinninghe Damste, Jaap S., Rijpstra, W. Irene C., Prahl, Fredrick, Schouten, Stefan Intact core tetraether membrane lipids of marine planktonic Crenarchaeota were quantified in water column-suspended particulate matter obtained from four depth intervals (~70, 500, 1,000 and 1,500 m) at seven stations in the northwestern Arabian Sea to investigate the distribution of the organisms at various depths. Maximum concentrations generally occurred at 500 m, near the top of the oxygen minimum zone, and the concentrations at this depth were, in most cases, slightly higher than those in surface waters. In contrast, lipids derived from eukaryotes (cholesterol) and from eukaryotes and bacteria (fatty acids) were at their highest concentrations in surface waters. This indicates that these crenarchaeotes are not restricted to the photic zone of the ocean, which is consistent with the results of recent molecular biological studies. Since the Arabian Sea has a strong oxygen minimum zone between 100 and 1,000 m, with minimum oxygen levels of <1 μM, the abundance of crenarchaeotal membrane lipids at 500 m suggests that planktonic Crenarchaeota are probably facultative anaerobes. The cell numbers we calculated from the concentrations of membrane lipids are similar to those reported for the Central Pacific Ocean, supporting the recent estimation of M. B. Karner, E. F. DeLong, and D. M. Karl (Nature 409:507–510, 2001) that the world’s oceans contain ca. 10²⁸ cells of planktonic Crenarchaeota. Title: Distribution of membrane lipids of planktonic Crenarchaeota in the Arabian Sea Author: Wakeham, Stuart G., Hopmans, Ellen C., Sinninghe Damste, Jaap S., Rijpstra, W. Irene C., Prahl, Fredrick, Schouten, Stefan Intact core tetraether membrane lipids of marine planktonic Crenarchaeota were quantified in water column-suspended particulate matter obtained from four depth intervals (~70, 500, 1,000 and 1,500 m) at seven stations in the northwestern Arabian Sea to investigate the distribution of the organisms at various depths. Maximum concentrations generally occurred at 500 m, near the top of the oxygen minimum zone, and the concentrations at this depth were, in most cases, slightly higher than those in surface waters. In contrast, lipids derived from eukaryotes (cholesterol) and from eukaryotes and bacteria (fatty acids) were at their highest concentrations in surface waters. This indicates that these crenarchaeotes are not restricted to the photic zone of the ocean, which is consistent with the results of recent molecular biological studies. Since the Arabian Sea has a strong oxygen minimum zone between 100 and 1,000 m, with minimum oxygen levels of <1 μM, the abundance of crenarchaeotal membrane lipids at 500 m suggests that planktonic Crenarchaeota are probably facultative anaerobes. The cell numbers we calculated from the concentrations of membrane lipids are similar to those reported for the Central Pacific Ocean, supporting the recent estimation of M. B. Karner, E. F. DeLong, and D. M. Karl (Nature 409:507–510, 2001) that the world’s oceans contain ca. 10²⁸ cells of planktonic Crenarchaeota. Close

• 33. [Article] Particle size distributions in a region of coastal upwelling analyzed by characteristic vectors

  Particle size distributions (8-105-μm diameter), chlorophyll a, and particulate carbon were measured off the Oregon coast during July 1973. The particle counts were transformed to volume concentration ...

  Citation × Citation Citation Abstract Copy Title: Particle size distributions in a region of coastal upwelling analyzed by characteristic vectors Author: Kitchen, James C., Zaneveld, J. Ronald, Menzies, David, Pak, Hasong Particle size distributions (8-105-μm diameter), chlorophyll a, and particulate carbon were measured off the Oregon coast during July 1973. The particle counts were transformed to volume concentration and then subjected to characteristic vector analysis. Ninety-two percent of the variance was accounted for by linear combinations of the first two characteristic vectors. Two weighting factors define the proportions of the two characteristic vectors which will, when added to the mean volume concentration curve, approximate the actual data for each sample. Variations in the first weighting factor correspond well with variations in total volume. Changes in the second weighting factor indicate which segment of the size range contains the largest proportion of the particulate volume. Comparison with temperature and salinity data indicated that the near surface water with proportionately large volumes of particles less than 20 μm was warmer and less saline than the surface waters with large volumes between 20 and 50 μm. High correlation with particulate carbon and chlorophyll suggests that in both cases a large proportion of the particles is phytoplankton. Title: Particle size distributions in a region of coastal upwelling analyzed by characteristic vectors Author: Kitchen, James C., Zaneveld, J. Ronald, Menzies, David, Pak, Hasong Particle size distributions (8-105-μm diameter), chlorophyll a, and particulate carbon were measured off the Oregon coast during July 1973. The particle counts were transformed to volume concentration and then subjected to characteristic vector analysis. Ninety-two percent of the variance was accounted for by linear combinations of the first two characteristic vectors. Two weighting factors define the proportions of the two characteristic vectors which will, when added to the mean volume concentration curve, approximate the actual data for each sample. Variations in the first weighting factor correspond well with variations in total volume. Changes in the second weighting factor indicate which segment of the size range contains the largest proportion of the particulate volume. Comparison with temperature and salinity data indicated that the near surface water with proportionately large volumes of particles less than 20 μm was warmer and less saline than the surface waters with large volumes between 20 and 50 μm. High correlation with particulate carbon and chlorophyll suggests that in both cases a large proportion of the particles is phytoplankton. Close

• 34. [Article] Vegetative filter strips near surface water in the Pacific Northwest

  Published September 2004. Reviewed July 2008. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog/catalog

  Citation × Citation Citation Abstract Copy Title: Vegetative filter strips near surface water in the Pacific Northwest Author: Cole, C. (Charles M.), Lins, Ryan D., Colquhoun, Jed, Oregon State University. Extension Service Published September 2004. Reviewed July 2008. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog/catalog Title: Vegetative filter strips near surface water in the Pacific Northwest Author: Cole, C. (Charles M.), Lins, Ryan D., Colquhoun, Jed, Oregon State University. Extension Service Published September 2004. Reviewed July 2008. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog/catalog Close

• 35. [Article] A comparison of the prevalence of infectious gastrointestinal disease and the quality of individual, surface source water systems in Lincoln County, Oregon

  This study was a comparison of the prevalence of infectious gastrointestinal disease and the quality of construction of individual, surface source water systems in Lincoln County, Oregon. Two measurement ...

  Citation × Citation Citation Abstract Copy Title: A comparison of the prevalence of infectious gastrointestinal disease and the quality of individual, surface source water systems in Lincoln County, Oregon Author: Nauman, Hal Eugene This study was a comparison of the prevalence of infectious gastrointestinal disease and the quality of construction of individual, surface source water systems in Lincoln County, Oregon. Two measurement instruments were developed for this study. An objective instrument was developed to determine if the water systems observed in the study were adequately or inadequately constructed. A second objective instrument was developed to determine if individuals interviewed in the study were ill with an infectious gastrointestinal disease. The Delphi Method was used to validate the two instruments, and was based on a concensus of opinions by a panel of experts regarding this subject matter. The sample population was identified through a systematic selection of dwellings using a Lincoln County Department of Engineers road map and a list of random numbers. Individuals were interviewed using the Surface Source Water System Gastrointestinal Disease Evaluation instrument to determine if they had an infectious gastrointestinal disease. The surface source water systems were evaluated using the Individual Surface Source Water System Evaluation Instrument to determine if they were adequately constructed. Subsequently, the individuals were categorized as being ill or not ill. The water systems were all categorized as being adequately or inadequately constructed. The chi square statistic was used to determine if there was a significant difference between the number of people with and without an infectious gastrointestinal disease using inadequately constructed individual, surface source water systems. Also, the chi square statistic was used to determine if there was a significant difference between the number of people with and without an infectious gastrointestinal disease using adequately constructed, individual, surface source water systems. The statistical analysis revealed that there were significantly more well people than ill people using both types of water systems at a significance level of 0.05. Because of a lack of clear differentiation in the data, the common public health concept that quality of construction of individual surface source water systems as a factor in the spread of infectious gastrointestinal diseases cannot be supported or refuted. A major recommendation was to repeat the study by examining the water directly using laboratory techniques. This would positively establish the presence or absence of a disease causing organism in the water system. A literature search by the author revealed that effective measurement instruments for evaluation of relationships of gastrointestinal diseases and well construction quality were not readily available. The instruments developed by the author may require further testing to yield more definitive data. Title: A comparison of the prevalence of infectious gastrointestinal disease and the quality of individual, surface source water systems in Lincoln County, Oregon Author: Nauman, Hal Eugene This study was a comparison of the prevalence of infectious gastrointestinal disease and the quality of construction of individual, surface source water systems in Lincoln County, Oregon. Two measurement instruments were developed for this study. An objective instrument was developed to determine if the water systems observed in the study were adequately or inadequately constructed. A second objective instrument was developed to determine if individuals interviewed in the study were ill with an infectious gastrointestinal disease. The Delphi Method was used to validate the two instruments, and was based on a concensus of opinions by a panel of experts regarding this subject matter. The sample population was identified through a systematic selection of dwellings using a Lincoln County Department of Engineers road map and a list of random numbers. Individuals were interviewed using the Surface Source Water System Gastrointestinal Disease Evaluation instrument to determine if they had an infectious gastrointestinal disease. The surface source water systems were evaluated using the Individual Surface Source Water System Evaluation Instrument to determine if they were adequately constructed. Subsequently, the individuals were categorized as being ill or not ill. The water systems were all categorized as being adequately or inadequately constructed. The chi square statistic was used to determine if there was a significant difference between the number of people with and without an infectious gastrointestinal disease using inadequately constructed individual, surface source water systems. Also, the chi square statistic was used to determine if there was a significant difference between the number of people with and without an infectious gastrointestinal disease using adequately constructed, individual, surface source water systems. The statistical analysis revealed that there were significantly more well people than ill people using both types of water systems at a significance level of 0.05. Because of a lack of clear differentiation in the data, the common public health concept that quality of construction of individual surface source water systems as a factor in the spread of infectious gastrointestinal diseases cannot be supported or refuted. A major recommendation was to repeat the study by examining the water directly using laboratory techniques. This would positively establish the presence or absence of a disease causing organism in the water system. A literature search by the author revealed that effective measurement instruments for evaluation of relationships of gastrointestinal diseases and well construction quality were not readily available. The instruments developed by the author may require further testing to yield more definitive data. Close

• 36. [Article] Sea surface water motion off Chile latitudes 18°S-40°S, revealed from satellite images of chlorophyll and temperature distribution

  The mesoscale sea-surface circulation pattern within 400 km off Chile and between 18°S and 40°S latitude is described using chlorophyll and temperature images from the Coastal Zone Color Scanner NIMBUS-7 ...

  Citation × Citation Citation Abstract Copy Title: Sea surface water motion off Chile latitudes 18°S-40°S, revealed from satellite images of chlorophyll and temperature distribution Author: Espinoza, Felix R. The mesoscale sea-surface circulation pattern within 400 km off Chile and between 18°S and 40°S latitude is described using chlorophyll and temperature images from the Coastal Zone Color Scanner NIMBUS-7 satellite. The data base is a set of four mosaics developed from band-3 (550 nm) images taken on June 4 and September 16, 1979 and January 14 and April 7, 1980, supplemented with one mosaic of sea-surface temperature distribution for the September mosaic, orbit 4526. Coastal eddies, upwelling zones and zones of onshore-offshore transport are clearly distinguished because a zone of low-pigment concentration water generally separates the highly pigmented near-shore upwelling zones from oceanic waters with pigment concentration in mid-range. The cause of the low-pigment water adjacent to upwelling zones is not known, but the absence of temperature differences between up-welled and low-pigmented water suggest a biological cause. Onshore jets of oceanic waters are traced from distances up to 300 km offshore to within, in places, a few tens of kilometers of the shoreline; width of the jets is of the order of 60 km. In general, these onshore jets are separated by plumes of near-shore surface water moving seaward, with plumes width on the order of 40 km also extending as far as 400 km offshore. Large eddies form off the leading edges of both onshore and offshore plumes, giving rise to a formation called a "hammerhead" structure. Onshore jets are consistent with the result of Inostroza (1972) which documents intrusions of warm oceanic surface waters as semi-stationary features off Coquimbo (30°S) and off Talcahuano (37°S). Lack of wind data for 1979-80 prevents a direct correlation of onshore-offshore plumes with regional wind stress data. Low level wind charts for the 1979-80 period are too coarse in resolution to yield correlations. However, stick diagrams were prepared from coastal wind station data for 1977. Both time and space variations in surface winds could be responsible for the patterns revealed in chlorophyll images. The existence of persistent but probably episodic onshore-offshore transport of surface waters to such large distances offshore have not been reported previously for Chilean waters. These must certainly impact directly the patterns of migrations of populations of major fishery resources such as the Jack Mackerel (Trachurus murphyi, common name Jurel, species. Title: Sea surface water motion off Chile latitudes 18°S-40°S, revealed from satellite images of chlorophyll and temperature distribution Author: Espinoza, Felix R. The mesoscale sea-surface circulation pattern within 400 km off Chile and between 18°S and 40°S latitude is described using chlorophyll and temperature images from the Coastal Zone Color Scanner NIMBUS-7 satellite. The data base is a set of four mosaics developed from band-3 (550 nm) images taken on June 4 and September 16, 1979 and January 14 and April 7, 1980, supplemented with one mosaic of sea-surface temperature distribution for the September mosaic, orbit 4526. Coastal eddies, upwelling zones and zones of onshore-offshore transport are clearly distinguished because a zone of low-pigment concentration water generally separates the highly pigmented near-shore upwelling zones from oceanic waters with pigment concentration in mid-range. The cause of the low-pigment water adjacent to upwelling zones is not known, but the absence of temperature differences between up-welled and low-pigmented water suggest a biological cause. Onshore jets of oceanic waters are traced from distances up to 300 km offshore to within, in places, a few tens of kilometers of the shoreline; width of the jets is of the order of 60 km. In general, these onshore jets are separated by plumes of near-shore surface water moving seaward, with plumes width on the order of 40 km also extending as far as 400 km offshore. Large eddies form off the leading edges of both onshore and offshore plumes, giving rise to a formation called a "hammerhead" structure. Onshore jets are consistent with the result of Inostroza (1972) which documents intrusions of warm oceanic surface waters as semi-stationary features off Coquimbo (30°S) and off Talcahuano (37°S). Lack of wind data for 1979-80 prevents a direct correlation of onshore-offshore plumes with regional wind stress data. Low level wind charts for the 1979-80 period are too coarse in resolution to yield correlations. However, stick diagrams were prepared from coastal wind station data for 1977. Both time and space variations in surface winds could be responsible for the patterns revealed in chlorophyll images. The existence of persistent but probably episodic onshore-offshore transport of surface waters to such large distances offshore have not been reported previously for Chilean waters. These must certainly impact directly the patterns of migrations of populations of major fishery resources such as the Jack Mackerel (Trachurus murphyi, common name Jurel, species. Close

• 37. [Article] Passive sampling devices as biological surrogates for evaluating seasonal bioavailability of hydrophobic organic contaminants in surface water

  Citation × Citation Citation Abstract Copy Title: Passive sampling devices as biological surrogates for evaluating seasonal bioavailability of hydrophobic organic contaminants in surface water Author: Sethajintanin, Doolalai Title: Passive sampling devices as biological surrogates for evaluating seasonal bioavailability of hydrophobic organic contaminants in surface water Author: Sethajintanin, Doolalai Close

• 38. [Article] ArikAidaD2011.pdf

  Citation × Citation Citation Abstract Copy Title: ArikAidaD2011.pdf Author: Arik, Aida D. Title: ArikAidaD2011.pdf Author: Arik, Aida D. Close

• 39. [Article] Appendix C - Stream Temperature Model.zip

  Citation × Citation Citation Abstract Copy Title: Appendix C - Stream Temperature Model.zip Author: Arik, Aida D. Title: Appendix C - Stream Temperature Model.zip Author: Arik, Aida D. Close

• 40. [Article] Appendix B - Data Collected 1-June 2008.zip

  Citation × Citation Citation Abstract Copy Title: Appendix B - Data Collected 1-June 2008.zip Author: Arik, Aida D. Title: Appendix B - Data Collected 1-June 2008.zip Author: Arik, Aida D. Close

• 41. [Article] Appendix B - Data Collected 2-Sept 2008.zip

  Citation × Citation Citation Abstract Copy Title: Appendix B - Data Collected 2-Sept 2008.zip Author: Arik, Aida D. Title: Appendix B - Data Collected 2-Sept 2008.zip Author: Arik, Aida D. Close

• 42. [Article] Appendix B - Data Collected 3-July 2009.zip

  Citation × Citation Citation Abstract Copy Title: Appendix B - Data Collected 3-July 2009.zip Author: Arik, Aida D. Title: Appendix B - Data Collected 3-July 2009.zip Author: Arik, Aida D. Close

• 43. [Article] Appendix B - Data Collected 4-Aug 2009.zip

  Citation × Citation Citation Abstract Copy Title: Appendix B - Data Collected 4-Aug 2009.zip Author: Arik, Aida D. Title: Appendix B - Data Collected 4-Aug 2009.zip Author: Arik, Aida D. Close

• 44. [Article] Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho

  In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders ...

  Citation × Citation Citation Abstract Copy Title: Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho Author: Inouye, Allison Marshall In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and identify strategies that may help mitigate the impacts. The 8,300 square kilometer region in central Idaho contains a mixture of public and private land ownership, a diversity of landcover ranging from steep forested headwaters to expansive desert shrublands to a concentrated area of urban development that has experienced a quadrupling of population since the 1970s. With nearly 60% of precipitation falling as winter snow, stakeholders expressed concern regarding the vulnerability of the quantity and timing of seasonal snowpack as well as surface water supplies used primarily for agricultural irrigation under projected climate change. Here, we achieve two objectives. The first is the development of a hydrologic model to represent the dynamics of the surface water system in the Big Wood Basin. We use the semi-distributed model Envision-Flow to represent surface water hydrology, reservoir operations, and agricultural irrigation. We calibrated the model using a multi-criteria objective function that considered three metrics related to streamflow and one metric related to snow water equivalent. The model achieved higher an efficiency of 0.74 for the main stem of the Big Wood River and 0.50 for the Camas Creek tributary during the validation period. The second objective is an analysis of the Big Wood Basin hydrology under alternative future climate scenarios. We forced the calibrated model with three downscaled CMIP5 climate model inputs representing a range of possible future conditions over the period 2010-2070. The climate models simulate an increase in basin average annual air temperature ranging from 1.6-5.7oC in the 2060s compared to the 1980-2009 average. The climate models show less of a clear trend regarding precipitation but in general, one model simulates precipitation patterns similar to historic, one is slightly wetter than historic, and one is slightly drier than historic by the mid-21st century. Under these future climate scenarios, the depth of April 1 SWE may decline by as much as 92% in the 2060s compared to the historic average. Mid to high elevations exhibit the largest reductions in SWE. Simulated streamflows show a shift in timing, with peak flows occurring up to three weeks earlier and center of timing from two to seven weeks earlier in the 2050-2069 period compared to the historic period. Reduced peak flows of 14-70% were simulated by mid-century. The simulated total annual streamflow, though, fell within the historic interquartile range for most years in the future period. These and other metrics considered suggest that the surface water hydrology of the Big Wood Basin is likely to be impacted by climate change. If the natural water storage provided by the annual snowpack is reduced and timing of streamflows shifts, water resource use and management may need to change in the future. This work provides a foundation from which to explore alternative management scenarios. The approach used here can be transferred to other watersheds to further assess how water resources may be affected by climate change. Title: Development of a hydrologic model to explore impacts of climate change on water resources in the Big Wood Basin, Idaho Author: Inouye, Allison Marshall In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and identify strategies that may help mitigate the impacts. The 8,300 square kilometer region in central Idaho contains a mixture of public and private land ownership, a diversity of landcover ranging from steep forested headwaters to expansive desert shrublands to a concentrated area of urban development that has experienced a quadrupling of population since the 1970s. With nearly 60% of precipitation falling as winter snow, stakeholders expressed concern regarding the vulnerability of the quantity and timing of seasonal snowpack as well as surface water supplies used primarily for agricultural irrigation under projected climate change. Here, we achieve two objectives. The first is the development of a hydrologic model to represent the dynamics of the surface water system in the Big Wood Basin. We use the semi-distributed model Envision-Flow to represent surface water hydrology, reservoir operations, and agricultural irrigation. We calibrated the model using a multi-criteria objective function that considered three metrics related to streamflow and one metric related to snow water equivalent. The model achieved higher an efficiency of 0.74 for the main stem of the Big Wood River and 0.50 for the Camas Creek tributary during the validation period. The second objective is an analysis of the Big Wood Basin hydrology under alternative future climate scenarios. We forced the calibrated model with three downscaled CMIP5 climate model inputs representing a range of possible future conditions over the period 2010-2070. The climate models simulate an increase in basin average annual air temperature ranging from 1.6-5.7oC in the 2060s compared to the 1980-2009 average. The climate models show less of a clear trend regarding precipitation but in general, one model simulates precipitation patterns similar to historic, one is slightly wetter than historic, and one is slightly drier than historic by the mid-21st century. Under these future climate scenarios, the depth of April 1 SWE may decline by as much as 92% in the 2060s compared to the historic average. Mid to high elevations exhibit the largest reductions in SWE. Simulated streamflows show a shift in timing, with peak flows occurring up to three weeks earlier and center of timing from two to seven weeks earlier in the 2050-2069 period compared to the historic period. Reduced peak flows of 14-70% were simulated by mid-century. The simulated total annual streamflow, though, fell within the historic interquartile range for most years in the future period. These and other metrics considered suggest that the surface water hydrology of the Big Wood Basin is likely to be impacted by climate change. If the natural water storage provided by the annual snowpack is reduced and timing of streamflows shifts, water resource use and management may need to change in the future. This work provides a foundation from which to explore alternative management scenarios. The approach used here can be transferred to other watersheds to further assess how water resources may be affected by climate change. Close

• 45. [Article] Distribution of suspended matter in the Panama basin

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Distribution of suspended matter in the Panama basin Author: Zaneveld, J. Ronald, Plank, William S., Pak, Hasong Copyrighted by American Geophysical Union. Title: Distribution of suspended matter in the Panama basin Author: Zaneveld, J. Ronald, Plank, William S., Pak, Hasong Copyrighted by American Geophysical Union. Close

• 46. [Article] Results of First Year of Wsda Pesticide Testing of Surface Waters in the Yakima Valley

  64th Annual Pacific Northwest Insect Management Conference, held January 3 and 4, 2005.

  Citation × Citation Citation Abstract Copy Title: Results of First Year of Wsda Pesticide Testing of Surface Waters in the Yakima Valley Author: Schreiber, Alan S. Year: 2005 64th Annual Pacific Northwest Insect Management Conference, held January 3 and 4, 2005. Title: Results of First Year of Wsda Pesticide Testing of Surface Waters in the Yakima Valley Author: Schreiber, Alan S. Year: 2005 64th Annual Pacific Northwest Insect Management Conference, held January 3 and 4, 2005. Close

• 47. [Article] Characterization of spring and surface water conductance : Whychus Creek from Pole Creek Ditch to the Camp Polk Meadow riparian area

  Poster from the 2006 Cascades student poster session

  Citation × Citation Citation Abstract Copy Title: Characterization of spring and surface water conductance : Whychus Creek from Pole Creek Ditch to the Camp Polk Meadow riparian area Author: Brown, Jason Poster from the 2006 Cascades student poster session Title: Characterization of spring and surface water conductance : Whychus Creek from Pole Creek Ditch to the Camp Polk Meadow riparian area Author: Brown, Jason Poster from the 2006 Cascades student poster session Close

• 48. [Article] Continuous monitoring and modeling to assess pesticide exposure in critical habitat for Pacific salmonids

  Pacific Northwest and California freshwater resources are key elements in the life history and ecology of Pacific salmon and steelhead listed as threatened or endangered under the Endangered Species Act. ...

  Citation × Citation Citation Abstract Copy Title: Continuous monitoring and modeling to assess pesticide exposure in critical habitat for Pacific salmonids Author: Janney, Philip Kenton Pacific Northwest and California freshwater resources are key elements in the life history and ecology of Pacific salmon and steelhead listed as threatened or endangered under the Endangered Species Act. Risk to listed Pacific salmonid species can be assessed by evaluating the spatial and temporal co-occurrence of salmonid species at sensitive life stages and pesticide concentrations at levels that may elicit adverse effects. Understanding the potential for the co-occurrence requires knowledge of pesticide use patterns and application methods, pesticide properties that influence environmental fate, as well as landscape/land management, edaphic, and climatic factors that influence off-site movement into surface water. Reported here is the use of a passive sampling device to monitor selected current use pesticides in surface water on a continuous basis. Passive sampling devices (PSDs) were deployed continuously in 5 watersheds within the Pudding River subbasin, critical habitat for the Upper Willamette River Chinook and Steelhead ESUs, between June 2010 and October 2011 in order to characterize the temporal trends in surface water concentrations. PSDs were deployed in off-channel habitats preferred by juvenile salmonids. The majority of the monitoring results were well below EPA aquatic life benchmarks, as well as levels of concern for listed salmonids. Using the EPA ecoregion framework watershed sensitivity to pesticide surface water loading was characterized. The Soil and Water Assessment Tool (SWAT) was used to assess the relationship between land management practices and PSD monitoring data collected in the Zollner Creek watershed. SWAT was evaluated under different parameterization scenarios representing increasing levels of local knowledge of the system in order to evaluate model performance in relation to average daily stream flow. Using spatially distributed precipitation data and incorporating engineered drainage features into model parameterization resulted in a satisfactory fit of average daily stream flow indicating satisfactory characterization of the watershed hydrology. SWAT was then used to simulate the fate of chlorpyrifos and trifluralin, the two most commonly detected pesticides in the PSD monitoring. The pattern of simulated time-weighted average (TWA) pesticide concentrations was similar to measured values. However, simulated pesticide TWA concentrations consistently underestimated measured values. The most likely source of this bias is underrepresented pesticide use practices. Title: Continuous monitoring and modeling to assess pesticide exposure in critical habitat for Pacific salmonids Author: Janney, Philip Kenton Pacific Northwest and California freshwater resources are key elements in the life history and ecology of Pacific salmon and steelhead listed as threatened or endangered under the Endangered Species Act. Risk to listed Pacific salmonid species can be assessed by evaluating the spatial and temporal co-occurrence of salmonid species at sensitive life stages and pesticide concentrations at levels that may elicit adverse effects. Understanding the potential for the co-occurrence requires knowledge of pesticide use patterns and application methods, pesticide properties that influence environmental fate, as well as landscape/land management, edaphic, and climatic factors that influence off-site movement into surface water. Reported here is the use of a passive sampling device to monitor selected current use pesticides in surface water on a continuous basis. Passive sampling devices (PSDs) were deployed continuously in 5 watersheds within the Pudding River subbasin, critical habitat for the Upper Willamette River Chinook and Steelhead ESUs, between June 2010 and October 2011 in order to characterize the temporal trends in surface water concentrations. PSDs were deployed in off-channel habitats preferred by juvenile salmonids. The majority of the monitoring results were well below EPA aquatic life benchmarks, as well as levels of concern for listed salmonids. Using the EPA ecoregion framework watershed sensitivity to pesticide surface water loading was characterized. The Soil and Water Assessment Tool (SWAT) was used to assess the relationship between land management practices and PSD monitoring data collected in the Zollner Creek watershed. SWAT was evaluated under different parameterization scenarios representing increasing levels of local knowledge of the system in order to evaluate model performance in relation to average daily stream flow. Using spatially distributed precipitation data and incorporating engineered drainage features into model parameterization resulted in a satisfactory fit of average daily stream flow indicating satisfactory characterization of the watershed hydrology. SWAT was then used to simulate the fate of chlorpyrifos and trifluralin, the two most commonly detected pesticides in the PSD monitoring. The pattern of simulated time-weighted average (TWA) pesticide concentrations was similar to measured values. However, simulated pesticide TWA concentrations consistently underestimated measured values. The most likely source of this bias is underrepresented pesticide use practices. Close

• 49. [Article] Silicon biogeochemistry in the open-ocean surface waters : insights from the Sargasso Sea and equatorial Pacific

  Diatoms are a ubiquitous group of plankton responsible for 20-40% of oceanic primary production, and a higher fraction of organic matter export to the ocean interior. Diatoms actively transport dissolved ...

  Citation × Citation Citation Abstract Copy Title: Silicon biogeochemistry in the open-ocean surface waters : insights from the Sargasso Sea and equatorial Pacific Author: Krause, Jeffrey W. Diatoms are a ubiquitous group of plankton responsible for 20-40% of oceanic primary production, and a higher fraction of organic matter export to the ocean interior. Diatoms actively transport dissolved inorganic silicon into their cells, and through the process of silicification (i.e. biogenic silica production) they build tough and intricate shells, known as frustules. With a global distribution and the ability to persist in high numerical abundances, diatoms dominate the biological cycling of Si in the oceans. The biogeochemical cycling of Si has been well studied in the coastal ocean, specifically in upwelling regions where diatoms are generally the dominant phytoplankton group. However, much less is known about the role diatoms play in the open ocean; which comprises the vast majority of the oceanic surface area. Outside of the Southern Ocean, only 11 studies (prior to 2003) directly examined surface-water Si biogeochemistry in the open ocean. Current knowledge about Si biogeochemistry in the open ocean suffers from what can only be described as gross under-sampling. This dissertation reports on the surface-water Si biogeochemistry in two open-ocean regions: the northwestern Sargasso Sea and the eastern equatorial Pacific. The three research chapters are linked by the examination of spatial or temporal variability in surface-water Si biogeochemistry. Chapters 2 and 4 examine scales of temporal variability in Si biogeochemistry in the Sargasso Sea. The results demonstrate that biogenic silica concentrations, and presumably Si biogeochemical processes, vary on daily, seasonal, multi-year (e.g. ~3-4 years), and decadal time scales. In Chapter 3 data were gathered over a ~2.6x106 km2 area (i.e. larger than the Bering Sea) in the equatorial Pacific. Within that area biogenic silica production showed little spatial or temporal variability. Additionally, the estimated contribution to new production (productivity supporting the export of organic matter to the ocean interior) by diatoms in this region was 4-10 times higher than the diatom contribution to total autotrophic biomass. Title: Silicon biogeochemistry in the open-ocean surface waters : insights from the Sargasso Sea and equatorial Pacific Author: Krause, Jeffrey W. Diatoms are a ubiquitous group of plankton responsible for 20-40% of oceanic primary production, and a higher fraction of organic matter export to the ocean interior. Diatoms actively transport dissolved inorganic silicon into their cells, and through the process of silicification (i.e. biogenic silica production) they build tough and intricate shells, known as frustules. With a global distribution and the ability to persist in high numerical abundances, diatoms dominate the biological cycling of Si in the oceans. The biogeochemical cycling of Si has been well studied in the coastal ocean, specifically in upwelling regions where diatoms are generally the dominant phytoplankton group. However, much less is known about the role diatoms play in the open ocean; which comprises the vast majority of the oceanic surface area. Outside of the Southern Ocean, only 11 studies (prior to 2003) directly examined surface-water Si biogeochemistry in the open ocean. Current knowledge about Si biogeochemistry in the open ocean suffers from what can only be described as gross under-sampling. This dissertation reports on the surface-water Si biogeochemistry in two open-ocean regions: the northwestern Sargasso Sea and the eastern equatorial Pacific. The three research chapters are linked by the examination of spatial or temporal variability in surface-water Si biogeochemistry. Chapters 2 and 4 examine scales of temporal variability in Si biogeochemistry in the Sargasso Sea. The results demonstrate that biogenic silica concentrations, and presumably Si biogeochemical processes, vary on daily, seasonal, multi-year (e.g. ~3-4 years), and decadal time scales. In Chapter 3 data were gathered over a ~2.6x106 km2 area (i.e. larger than the Bering Sea) in the equatorial Pacific. Within that area biogenic silica production showed little spatial or temporal variability. Additionally, the estimated contribution to new production (productivity supporting the export of organic matter to the ocean interior) by diatoms in this region was 4-10 times higher than the diatom contribution to total autotrophic biomass. Close

• 50. [Article] Water quality effects of hyporheic processing

  "PB2000-107420."

  Citation × Citation Citation Abstract Copy Title: Water quality effects of hyporheic processing Author: Wigington, P.J., Landers, Dixon, Fernald, Alexander "PB2000-107420." Title: Water quality effects of hyporheic processing Author: Wigington, P.J., Landers, Dixon, Fernald, Alexander "PB2000-107420." Close

• 51. [Article] A study of the seasonal variation in temperature and salinity along the Oregon - Northern California coast

  This study examines the seasonal variability in temperature and salinity of the nearshore waters off Oregon and Northern California. Specifically, temperature and salinity variations during summer and winter ...

  Citation × Citation Citation Abstract Copy Title: A study of the seasonal variation in temperature and salinity along the Oregon - Northern California coast Author: Bourke, Robert H. This study examines the seasonal variability in temperature and salinity of the nearshore waters off Oregon and Northern California. Specifically, temperature and salinity variations during summer and winter were ana1yzed from data gathered at shore stations along the coast and from hydrographic data collected within 25 nautical miles of shore. At each of five shore stations a modal cell technique was used to establish the temperature-salinity characteristics of the "normal" water type existing at each station during summer and winter. A classification scheme was employed to determine what local processes were influential in altering the "normal" T-S characteristics at each station. In summer mixing with Columbia River plume water was found to be the major modifying process along the Northern Oregon coast. Off Central and Southern Oregon local heating and mixing with water from the shelf/slope region were found to be most influential. In winter dilution due to precipitation and subsequent runoff is the major modifying factor along the entire coast except off Northern Oregon where mixing with shelf/slope waters is slightly more influential. The temperature and salinity structure of the near surface waters (< 200 meters) was examined for four latitudinal zones off the Oregon- Northern California coast. Within each zone profiles were constructed at 5, 15, and 25 nautical miles offshore. Surface waters are warmer and more saline in summer than in winter. Surface temperatures increase seaward in both seasons. Surface salinities increase seaward only during winter; in summer the increase is shoreward. Offshore gradients of temperature and salinity are one to two orders of magnitude greater than longshore gradients. A strong thermocline to 30 meters and a strong halocline to 75 meters is present in summer. In winter the water is isothermal to 50 meters while a strong halocline is present to 100 meters. Below these levels temperatures and salinities continue to slowly decrease and increase, respectively, until at 200 meters they become constant throughout the study area. Variability with distance from shore is significant only in summer and is constrained to the upper 150 meters of the water column. Title: A study of the seasonal variation in temperature and salinity along the Oregon - Northern California coast Author: Bourke, Robert H. This study examines the seasonal variability in temperature and salinity of the nearshore waters off Oregon and Northern California. Specifically, temperature and salinity variations during summer and winter were ana1yzed from data gathered at shore stations along the coast and from hydrographic data collected within 25 nautical miles of shore. At each of five shore stations a modal cell technique was used to establish the temperature-salinity characteristics of the "normal" water type existing at each station during summer and winter. A classification scheme was employed to determine what local processes were influential in altering the "normal" T-S characteristics at each station. In summer mixing with Columbia River plume water was found to be the major modifying process along the Northern Oregon coast. Off Central and Southern Oregon local heating and mixing with water from the shelf/slope region were found to be most influential. In winter dilution due to precipitation and subsequent runoff is the major modifying factor along the entire coast except off Northern Oregon where mixing with shelf/slope waters is slightly more influential. The temperature and salinity structure of the near surface waters (< 200 meters) was examined for four latitudinal zones off the Oregon- Northern California coast. Within each zone profiles were constructed at 5, 15, and 25 nautical miles offshore. Surface waters are warmer and more saline in summer than in winter. Surface temperatures increase seaward in both seasons. Surface salinities increase seaward only during winter; in summer the increase is shoreward. Offshore gradients of temperature and salinity are one to two orders of magnitude greater than longshore gradients. A strong thermocline to 30 meters and a strong halocline to 75 meters is present in summer. In winter the water is isothermal to 50 meters while a strong halocline is present to 100 meters. Below these levels temperatures and salinities continue to slowly decrease and increase, respectively, until at 200 meters they become constant throughout the study area. Variability with distance from shore is significant only in summer and is constrained to the upper 150 meters of the water column. Close

• 52. [Article] Late quaternary changes in the oceanography of the eastern tropical Pacific

  Factor analysis of radiolarian species from the tops of 34 gravity cores in the area extending from 5°N to 45°N, 95°W to 155°W, yields five factor assemblages which are related to the present surface circulation: 1) ...

  Citation × Citation Citation Abstract Copy Title: Late quaternary changes in the oceanography of the eastern tropical Pacific Author: Wenkam, Chiye R. Factor analysis of radiolarian species from the tops of 34 gravity cores in the area extending from 5°N to 45°N, 95°W to 155°W, yields five factor assemblages which are related to the present surface circulation: 1) a Pacific Equatorial Water assemblage; 2) a California Current assemblage; 3) a North Equatorial Current assemblage; 4) a Tropical Surface Water assemblage; 5) an oxygen minimum layer assemblage. A sixth assemblage appears to be the result of dissolution. The variation of these factors through the late Pleistocene is based on the analysis of samples from two cores. Transfer functions which relate core top assemblages to temperature at the sea surface and at 130 m depth were used to determine paleotemperatures. Stratigraphic control was provided by oxygen isotope analysis of planktonic foraminifera from one core, Synchronous levels in the other core were determined from biostratigraphic correlation of the variations in the abundance of three species of radiolaria between cores. A reconstruction of the paleoceanography based on the results of the above analyses indicates that during the last glacial maximum (18,000 yrs BP): 1) sea surface temperatures were slightly lower than today; 2) the areal extent of warm Pacific Equatorial water and Tropical Surface water was diminished; 3) the California Current, North Equatorial Current, and the Equatorial Current were stronger than at present; 4) there was an increase in the thermal gradient in the thermocline and/or an increase in the depth of the mixed layer; 5) air and sea surface circulation patterns were constricted and experienced minimal north-south oscillation. Title: Late quaternary changes in the oceanography of the eastern tropical Pacific Author: Wenkam, Chiye R. Factor analysis of radiolarian species from the tops of 34 gravity cores in the area extending from 5°N to 45°N, 95°W to 155°W, yields five factor assemblages which are related to the present surface circulation: 1) a Pacific Equatorial Water assemblage; 2) a California Current assemblage; 3) a North Equatorial Current assemblage; 4) a Tropical Surface Water assemblage; 5) an oxygen minimum layer assemblage. A sixth assemblage appears to be the result of dissolution. The variation of these factors through the late Pleistocene is based on the analysis of samples from two cores. Transfer functions which relate core top assemblages to temperature at the sea surface and at 130 m depth were used to determine paleotemperatures. Stratigraphic control was provided by oxygen isotope analysis of planktonic foraminifera from one core, Synchronous levels in the other core were determined from biostratigraphic correlation of the variations in the abundance of three species of radiolaria between cores. A reconstruction of the paleoceanography based on the results of the above analyses indicates that during the last glacial maximum (18,000 yrs BP): 1) sea surface temperatures were slightly lower than today; 2) the areal extent of warm Pacific Equatorial water and Tropical Surface water was diminished; 3) the California Current, North Equatorial Current, and the Equatorial Current were stronger than at present; 4) there was an increase in the thermal gradient in the thermocline and/or an increase in the depth of the mixed layer; 5) air and sea surface circulation patterns were constricted and experienced minimal north-south oscillation. Close

• 53. [Article] Assimilative Capacity Modeling in Support of the Georgia Comprehensive State-Wide Water Management Plan

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: Assimilative Capacity Modeling in Support of the Georgia Comprehensive State-Wide Water Management Plan Author: Davie, Steven, Booth, Elizabeth A., Watson, Brian, Wyss, Jeremy Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: Assimilative Capacity Modeling in Support of the Georgia Comprehensive State-Wide Water Management Plan Author: Davie, Steven, Booth, Elizabeth A., Watson, Brian, Wyss, Jeremy Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 54. [Article] Shallow Aquifer Recharge from Irrigation in a Semi-arid Agricultural Valley in New Mexico, USA

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American Society of Civil Engineers and can be found at: http://cedb.asce.o...

  Citation × Citation Citation Abstract Copy Title: Shallow Aquifer Recharge from Irrigation in a Semi-arid Agricultural Valley in New Mexico, USA Author: Ochoa, Carlos G., Shukla, Manoj K., Guldan, Steven J., Fernald, Alexander G., Tidwell, Vincent C. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American Society of Civil Engineers and can be found at: http://cedb.asce.org/cgi/WWWdisplay.cgi?310565. Title: Shallow Aquifer Recharge from Irrigation in a Semi-arid Agricultural Valley in New Mexico, USA Author: Ochoa, Carlos G., Shukla, Manoj K., Guldan, Steven J., Fernald, Alexander G., Tidwell, Vincent C. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American Society of Civil Engineers and can be found at: http://cedb.asce.org/cgi/WWWdisplay.cgi?310565. Close

• 55. [Article] Nitrate and water under terraced dryland wheat production in Oregon

  Dry land agriculture using summer fallow is a common crop production practice in the Columbia Plateau region of eastern Oregon. Farmed-over level terraces are used to control surface water runoff and soil ...

  Citation × Citation Citation Abstract Copy Title: Nitrate and water under terraced dryland wheat production in Oregon Author: Strock, Jeffrey S. Dry land agriculture using summer fallow is a common crop production practice in the Columbia Plateau region of eastern Oregon. Farmed-over level terraces are used to control surface water runoff and soil erosion. More than 70 percent of the average annual precipitation around Pendleton, Oregon (350 - 400 mm) falls as low intensity, long duration rainfall from September to March. Wetter soil zones typically occur above and below the terrace. These areas have a higher potential for crop production as well as for movement of chemicals to ground water and to surface water where seepage occurs. The extra nitrogen or water that could accumulate in these areas needs to be considered in managing these areas. The first objective of this study was to measure the distribution of nitrate nitrogen (NO₃-N) and water in relation to farmed-over level terraces, and infer potential solute flow patterns from changes in the measured distributions over time. The second objective was to make recommendations regarding management practices required for specific field locations to maximize crop production and minimize negative impacts on groundwater quality. Results indicate NO⁻₃ concentrations following harvest were < 4 mg kg⁻¹ of soil. Equivalent to soil solution concentrations between 27 and 20 mg L⁻¹ at 15 and 20 percent volumetric water content, respectively. Limited deep percolation of NO⁻₃ occurred below the root zone between harvest and planting. The NO⁻₃ concentrations below the root zone were < 1 to 15 mg kg⁻¹ following the summer fallow period. In August 1993, evidence exists that shows N applied fertilizer moved out of the surface 0.3 m and deeper into the profile. The redistribution of NO⁻₃ in the terrace channels of transects 1 and 2 strongly support this. Soil profiles that contain high residual concentrations of NO₃-N during the fallow period increase the potential for NO₃-N leaching below the root zone. Unusually heavy precipitation during normally dry periods or above normal winter precipitation increases the potential for NO₃-N leaching below the root zone. Title: Nitrate and water under terraced dryland wheat production in Oregon Author: Strock, Jeffrey S. Dry land agriculture using summer fallow is a common crop production practice in the Columbia Plateau region of eastern Oregon. Farmed-over level terraces are used to control surface water runoff and soil erosion. More than 70 percent of the average annual precipitation around Pendleton, Oregon (350 - 400 mm) falls as low intensity, long duration rainfall from September to March. Wetter soil zones typically occur above and below the terrace. These areas have a higher potential for crop production as well as for movement of chemicals to ground water and to surface water where seepage occurs. The extra nitrogen or water that could accumulate in these areas needs to be considered in managing these areas. The first objective of this study was to measure the distribution of nitrate nitrogen (NO₃-N) and water in relation to farmed-over level terraces, and infer potential solute flow patterns from changes in the measured distributions over time. The second objective was to make recommendations regarding management practices required for specific field locations to maximize crop production and minimize negative impacts on groundwater quality. Results indicate NO⁻₃ concentrations following harvest were < 4 mg kg⁻¹ of soil. Equivalent to soil solution concentrations between 27 and 20 mg L⁻¹ at 15 and 20 percent volumetric water content, respectively. Limited deep percolation of NO⁻₃ occurred below the root zone between harvest and planting. The NO⁻₃ concentrations below the root zone were < 1 to 15 mg kg⁻¹ following the summer fallow period. In August 1993, evidence exists that shows N applied fertilizer moved out of the surface 0.3 m and deeper into the profile. The redistribution of NO⁻₃ in the terrace channels of transects 1 and 2 strongly support this. Soil profiles that contain high residual concentrations of NO₃-N during the fallow period increase the potential for NO₃-N leaching below the root zone. Unusually heavy precipitation during normally dry periods or above normal winter precipitation increases the potential for NO₃-N leaching below the root zone. Close

• 56. [Article] Chlorophyll enchancement and mixing associated with meanders of the shelf break front in the Mid-Atlantic Bight

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Chlorophyll enchancement and mixing associated with meanders of the shelf break front in the Mid-Atlantic Bight Author: Yoder, J. A., Cornillon, P. C., Barth, John A., Ryan, J. P. copyrighted by American Geophysical Union Title: Chlorophyll enchancement and mixing associated with meanders of the shelf break front in the Mid-Atlantic Bight Author: Yoder, J. A., Cornillon, P. C., Barth, John A., Ryan, J. P. copyrighted by American Geophysical Union Close

• 57. [Article] Anthropogenic CO₂ invasion into the northeast Pacific based on concurrent δ¹³CDIC and nutrient profiles from the California Current

  The stable isotopic signature of dissolved inorganic carbon (δ¹³CDIC) in the northeast Pacific Ocean is lower in near-surface waters by 1.1‰ relative to values predicted from global oceanic trends of ...

  Citation × Citation Citation Abstract Copy Title: Anthropogenic CO₂ invasion into the northeast Pacific based on concurrent δ¹³CDIC and nutrient profiles from the California Current Author: Wheeler, Patricia A., Key, R. M., Mix, Alan C., Ortiz, Joseph D. The stable isotopic signature of dissolved inorganic carbon (δ¹³CDIC) in the northeast Pacific Ocean is lower in near-surface waters by 1.1‰ relative to values predicted from global oceanic trends of δ¹³CDIC versus nutrients. A combination of anthropogenic carbon uptake from the atmosphere and thermodynamic, air-sea gas exchange processes in different water mass source areas account for the isotopic depletion. Here we evaluate the efficacy of using a concurrent nutrient-δ¹³C strategy to separate these two effects, with the goal of improving estimates of anthropogenic carbon uptake over the course of the Industrial Revolution. In depth profiles from the sea surface to 2500 m at four stations across the California Current (42ºN), nitrate, rather than phosphate, is best correlated to δ¹³CDIC providing the best choice for this experiment. On the basis of an assumption of no anthropogenic carbon in North Pacific Deep Waters between 1000–2500 m depth (potential densities, σθ ~ 27.3–27.7), the “anthropogenic – preanthropogenic” carbon isotope shift (∆δ¹³Ca–p) in near-surface waters of the northeast Pacific is inferred to be -0.62 ± 0.17‰, while the thermodynamic air-sea gas exchange signature is estimated at -0.48 ± 0.17‰. Values of ∆δ¹³Ca–p (similar to the regional patterns of ∆¹4C and Tritium penetration) approach zero for σθ > 26.8, indicating little penetration of anthropogenic carbon into the North pacific Intermediate Water or the upper North pacific Deep Water. Our results suggest an upper North Pacific sink of anthropogenic carbon over the past ~200 years that is ~40% greater than that estimated for the interval between ~1970 and ~1990 by Quay et al. [1992]. Our estimate of the North Pacific inventory of anthropogenic carbon, added to published estimates from the North Atlantic and Indian Ocean, is smaller than model predictions of the total carbon sink, suggesting that a significant portion of anthropogenic carbon enters the deep sea via the Southern Ocean. Title: Anthropogenic CO₂ invasion into the northeast Pacific based on concurrent δ¹³CDIC and nutrient profiles from the California Current Author: Wheeler, Patricia A., Key, R. M., Mix, Alan C., Ortiz, Joseph D. The stable isotopic signature of dissolved inorganic carbon (δ¹³CDIC) in the northeast Pacific Ocean is lower in near-surface waters by 1.1‰ relative to values predicted from global oceanic trends of δ¹³CDIC versus nutrients. A combination of anthropogenic carbon uptake from the atmosphere and thermodynamic, air-sea gas exchange processes in different water mass source areas account for the isotopic depletion. Here we evaluate the efficacy of using a concurrent nutrient-δ¹³C strategy to separate these two effects, with the goal of improving estimates of anthropogenic carbon uptake over the course of the Industrial Revolution. In depth profiles from the sea surface to 2500 m at four stations across the California Current (42ºN), nitrate, rather than phosphate, is best correlated to δ¹³CDIC providing the best choice for this experiment. On the basis of an assumption of no anthropogenic carbon in North Pacific Deep Waters between 1000–2500 m depth (potential densities, σθ ~ 27.3–27.7), the “anthropogenic – preanthropogenic” carbon isotope shift (∆δ¹³Ca–p) in near-surface waters of the northeast Pacific is inferred to be -0.62 ± 0.17‰, while the thermodynamic air-sea gas exchange signature is estimated at -0.48 ± 0.17‰. Values of ∆δ¹³Ca–p (similar to the regional patterns of ∆¹4C and Tritium penetration) approach zero for σθ > 26.8, indicating little penetration of anthropogenic carbon into the North pacific Intermediate Water or the upper North pacific Deep Water. Our results suggest an upper North Pacific sink of anthropogenic carbon over the past ~200 years that is ~40% greater than that estimated for the interval between ~1970 and ~1990 by Quay et al. [1992]. Our estimate of the North Pacific inventory of anthropogenic carbon, added to published estimates from the North Atlantic and Indian Ocean, is smaller than model predictions of the total carbon sink, suggesting that a significant portion of anthropogenic carbon enters the deep sea via the Southern Ocean. Close

• 58. [Article] CTD and velocity surveys of seaward jets off Northern California, July 1981 and 1982

  Two mesoscale surveys were conducted (in July 1981 and July 1982) near Point Arena, California, to determine the structure and circulation associated with tongues of cold surface water extending seaward from ...

  Citation × Citation Citation Abstract Copy Title: CTD and velocity surveys of seaward jets off Northern California, July 1981 and 1982 Author: Huyer, Adriana, 1945-, Kosro, P. Michael, 1951- Two mesoscale surveys were conducted (in July 1981 and July 1982) near Point Arena, California, to determine the structure and circulation associated with tongues of cold surface water extending seaward from the coastal zone. Both surveys were designed at sea on the basis of available satellite IR data, and each was completed in less than a week. Sampling extended 100 km alongshore and 150 km (1981) to 250 km (1982) offshore, and included conductivity, temperature, and depth casts to 500 dbar, and continuous ocean current profiling to 150 m by means of a Doppler acoustic log. Both surveys showed that the tongues of cold water seen in the satellite images were the surface manifestation of hydrographic and current anomalies that extended to a depth of at least 100 m. In each case, strong seaward flow was observed along the northern edge of the cold tongue, which also marked a shallow water mass boundary between low-salinity (< 32.8 ppt) surface waters to the north and high-salinity (> 33.2 ppt) waters to the south. The seaward jets were very strong (up to 80 cm/s) and narrow (30 km), with strong shears (up to 10- 2 S- 1 in the vertical and up to 10^(-4)/s in the horizontal). They were largely geostrophic, had transports exceeding 1.5 sverdrups, and can persist for 2-3 weeks. The seaward jets seemed to be continuous with southward flowing alongshore coastal jets. There is evidence that the seaward jets are recurrent features in the vicinity of Point Arena. Title: CTD and velocity surveys of seaward jets off Northern California, July 1981 and 1982 Author: Huyer, Adriana, 1945-, Kosro, P. Michael, 1951- Two mesoscale surveys were conducted (in July 1981 and July 1982) near Point Arena, California, to determine the structure and circulation associated with tongues of cold surface water extending seaward from the coastal zone. Both surveys were designed at sea on the basis of available satellite IR data, and each was completed in less than a week. Sampling extended 100 km alongshore and 150 km (1981) to 250 km (1982) offshore, and included conductivity, temperature, and depth casts to 500 dbar, and continuous ocean current profiling to 150 m by means of a Doppler acoustic log. Both surveys showed that the tongues of cold water seen in the satellite images were the surface manifestation of hydrographic and current anomalies that extended to a depth of at least 100 m. In each case, strong seaward flow was observed along the northern edge of the cold tongue, which also marked a shallow water mass boundary between low-salinity (< 32.8 ppt) surface waters to the north and high-salinity (> 33.2 ppt) waters to the south. The seaward jets were very strong (up to 80 cm/s) and narrow (30 km), with strong shears (up to 10- 2 S- 1 in the vertical and up to 10^(-4)/s in the horizontal). They were largely geostrophic, had transports exceeding 1.5 sverdrups, and can persist for 2-3 weeks. The seaward jets seemed to be continuous with southward flowing alongshore coastal jets. There is evidence that the seaward jets are recurrent features in the vicinity of Point Arena. Close

• 59. [Article] Air-water CO₂ fluxes in the microtidal Neuse River Estuary, North Carolina

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/.

  Citation × Citation Citation Abstract Copy Title: Air-water CO₂ fluxes in the microtidal Neuse River Estuary, North Carolina Author: Paerl, Hans W., Hales, Burke, Crosswell, Joseph R., Wetz, Michael S. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/. Title: Air-water CO₂ fluxes in the microtidal Neuse River Estuary, North Carolina Author: Paerl, Hans W., Hales, Burke, Crosswell, Joseph R., Wetz, Michael S. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/jgr/. Close

• 60. [Article] Wind-driven transport pathways for Eurasian Arctic river discharge

  copyrighted by the American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Wind-driven transport pathways for Eurasian Arctic river discharge Author: Muench, Robin D., Mensch, Manfred, Guay, Christopher K. H., Falkner, Kelly, Bayer, Reinhold, Frank, Markus copyrighted by the American Geophysical Union Title: Wind-driven transport pathways for Eurasian Arctic river discharge Author: Muench, Robin D., Mensch, Manfred, Guay, Christopher K. H., Falkner, Kelly, Bayer, Reinhold, Frank, Markus copyrighted by the American Geophysical Union Close

• 61. [Article] Meridional fluxes of dissolved silicon in the southern ocean

  Meridional fluxes of silica across the Southern Ocean polar front are attributed to two different processes which generally act in opposite directions. Equatorward low frequency fluxes of silica inferred ...

  Citation × Citation Citation Abstract Copy Title: Meridional fluxes of dissolved silicon in the southern ocean Author: Jennings, Joe C. Meridional fluxes of silica across the Southern Ocean polar front are attributed to two different processes which generally act in opposite directions. Equatorward low frequency fluxes of silica inferred from ISOS current meter data in the Drake Passage are approximately balanced by poleward meridional diffusion of silica along surfaces of constant potential density. Considering only these two processes, a balance of the silicon budget in the Circumpolar Current can be achieved. The poleward diffusive flux along shoaling density surfaces may uaintain the high silicon concentrations characteristic of Antarctic surface waters south of the frontal zone. Title: Meridional fluxes of dissolved silicon in the southern ocean Author: Jennings, Joe C. Meridional fluxes of silica across the Southern Ocean polar front are attributed to two different processes which generally act in opposite directions. Equatorward low frequency fluxes of silica inferred from ISOS current meter data in the Drake Passage are approximately balanced by poleward meridional diffusion of silica along surfaces of constant potential density. Considering only these two processes, a balance of the silicon budget in the Circumpolar Current can be achieved. The poleward diffusive flux along shoaling density surfaces may uaintain the high silicon concentrations characteristic of Antarctic surface waters south of the frontal zone. Close

• 62. [Article] Flow-Solute : A Tool for Exploring the Effects of Nitrogen Management in Alternative Future Scenarios

  Surface water quality is a growing concern in the Willamette River Basin and elsewhere. The region's growing population is dependent on the availability of clean water for drinking water, irrigation, wastewater ...

  Citation × Citation Citation Abstract Copy Title: Flow-Solute : A Tool for Exploring the Effects of Nitrogen Management in Alternative Future Scenarios Author: Wentworth, Andrew Michael Surface water quality is a growing concern in the Willamette River Basin and elsewhere. The region's growing population is dependent on the availability of clean water for drinking water, irrigation, wastewater dilution, and wildlife habitat. Watershed management to produce economic goods and environmental services requires an understanding of basic hydrologic processes in addition to tools that accurately represent the interactions between human activity, biophysical processes, and climate change. In this study we developed a plug-in for the Envision modeling framework to explore where interactions between climate change and human activities are most likely to result in impaired water quality. This study has two primary objectives. The first is to develop a plug-in for Envision that can accurately simulate the effect of agricultural practices (e.g. fertilizer application rates and timing, crop selection, etc.) on the system's nitrogen budget. The second objective is to explore the landscape response to three future scenarios of changing climate, agricultural practices, and conservation actions as measured by nitrogen loading to surface waters in the Calapooia River Basin. The model we developed for this study was created by integrating algorithms from two widely used models: a conceptual hydrologic model and a nitrogen dynamics model. A number of changes were required to merge the two models and the accuracy of streamflow predictions suffered. The result of the scenario analysis was consistent with our expectations beginning the study: warmer and wetter climate scenarios were associated with higher annual nitrogen export rates, and policies that resulted in lower fertilizer application led to a decrease in annual nitrogen export rates. Title: Flow-Solute : A Tool for Exploring the Effects of Nitrogen Management in Alternative Future Scenarios Author: Wentworth, Andrew Michael Surface water quality is a growing concern in the Willamette River Basin and elsewhere. The region's growing population is dependent on the availability of clean water for drinking water, irrigation, wastewater dilution, and wildlife habitat. Watershed management to produce economic goods and environmental services requires an understanding of basic hydrologic processes in addition to tools that accurately represent the interactions between human activity, biophysical processes, and climate change. In this study we developed a plug-in for the Envision modeling framework to explore where interactions between climate change and human activities are most likely to result in impaired water quality. This study has two primary objectives. The first is to develop a plug-in for Envision that can accurately simulate the effect of agricultural practices (e.g. fertilizer application rates and timing, crop selection, etc.) on the system's nitrogen budget. The second objective is to explore the landscape response to three future scenarios of changing climate, agricultural practices, and conservation actions as measured by nitrogen loading to surface waters in the Calapooia River Basin. The model we developed for this study was created by integrating algorithms from two widely used models: a conceptual hydrologic model and a nitrogen dynamics model. A number of changes were required to merge the two models and the accuracy of streamflow predictions suffered. The result of the scenario analysis was consistent with our expectations beginning the study: warmer and wetter climate scenarios were associated with higher annual nitrogen export rates, and policies that resulted in lower fertilizer application led to a decrease in annual nitrogen export rates. Close

• 63. [Article] Primary productivity in the southeast Pacific Ocean : effects of enhanced ultraviolet-B radiation

  Anthropogenic releases of trace gases into the atmosphere are causing a decrease in stratospheric ozone concentrations and a subsequent increase in solar ultraviolet-B (UV-B)(280-320 nm) radiation reaching ...

  Citation × Citation Citation Abstract Copy Title: Primary productivity in the southeast Pacific Ocean : effects of enhanced ultraviolet-B radiation Author: Behrenfeld, Mike J. Anthropogenic releases of trace gases into the atmosphere are causing a decrease in stratospheric ozone concentrations and a subsequent increase in solar ultraviolet-B (UV-B)(280-320 nm) radiation reaching the earth's surface. The objective of this study was to determine the acute effects of enhanced UV-B radiation on the primary production of natural marine phytoplankton assemblages sampled over a wide latitudinal gradient and incubated under ambient levels of photosynthetically active radiation (PAR). Samples were collected approximately every 2 to 4° latitude in the southeast Pacific. Primary production was measured using the carbon-14 light and dark bottle technique. Fluorescent sunlamps were used to enhance the dose of UV-B radiation above ambient. Samples were maintained at ambient surface water temperature in a flow-through incubation tank. Enhanced UV-B radiation caused a significant mean decrease of 34% in surface water primary production. Decreases in primary production increased with and with increasing assimilation efficiencies. Results indicate that predicted increases in ambient solar UV-B radiation resulting from stratospheric ozone depletion could result in mean annual decreases of near-surface oceanic primary production of less than 1% near the equator to more than 32% at high southern latitudes. Title: Primary productivity in the southeast Pacific Ocean : effects of enhanced ultraviolet-B radiation Author: Behrenfeld, Mike J. Anthropogenic releases of trace gases into the atmosphere are causing a decrease in stratospheric ozone concentrations and a subsequent increase in solar ultraviolet-B (UV-B)(280-320 nm) radiation reaching the earth's surface. The objective of this study was to determine the acute effects of enhanced UV-B radiation on the primary production of natural marine phytoplankton assemblages sampled over a wide latitudinal gradient and incubated under ambient levels of photosynthetically active radiation (PAR). Samples were collected approximately every 2 to 4° latitude in the southeast Pacific. Primary production was measured using the carbon-14 light and dark bottle technique. Fluorescent sunlamps were used to enhance the dose of UV-B radiation above ambient. Samples were maintained at ambient surface water temperature in a flow-through incubation tank. Enhanced UV-B radiation caused a significant mean decrease of 34% in surface water primary production. Decreases in primary production increased with and with increasing assimilation efficiencies. Results indicate that predicted increases in ambient solar UV-B radiation resulting from stratospheric ozone depletion could result in mean annual decreases of near-surface oceanic primary production of less than 1% near the equator to more than 32% at high southern latitudes. Close

• 64. [Article] Distribution and variability of iron input to Oregon coastal waters during the upwelling season

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Distribution and variability of iron input to Oregon coastal waters during the upwelling season Author: Schwartz, Roseanne, Hales, Burke, Chase, Zanna, Cowles, Timothy J., van Geen, Alexander Copyrighted by American Geophysical Union. Title: Distribution and variability of iron input to Oregon coastal waters during the upwelling season Author: Schwartz, Roseanne, Hales, Burke, Chase, Zanna, Cowles, Timothy J., van Geen, Alexander Copyrighted by American Geophysical Union. Close

• 65. [Article] Heat and mass balances of the South Atlantic Ocean calculated from a numerical model

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Heat and mass balances of the South Atlantic Ocean calculated from a numerical model Author: Matano, Ricardo P., Philander, S. George H. copyrighted by American Geophysical Union Title: Heat and mass balances of the South Atlantic Ocean calculated from a numerical model Author: Matano, Ricardo P., Philander, S. George H. copyrighted by American Geophysical Union Close

• 66. [Article] Depth Distribution of Oceanic Shrimps (Decapoda ; Natantia) off Oregon

  Sixteen species of oceanic shrimps, seven Penaeidea and nine Caridea, appeared in 244 collections made within the upper 1500 m at one station in the northeast Pacific off Oregon. Most of the species were ...

  Citation × Citation Citation Abstract Copy Title: Depth Distribution of Oceanic Shrimps (Decapoda ; Natantia) off Oregon Author: Forss, Carl A., Pearcy, William G. Sixteen species of oceanic shrimps, seven Penaeidea and nine Caridea, appeared in 244 collections made within the upper 1500 m at one station in the northeast Pacific off Oregon. Most of the species were primarily mesopelagic in distribution. The most abundant species, Sergestes similis, was the only shrimp common in epipelagic waters at night and the only species clearly demonstrating did vertical migrations. Night catches exceeded day catches in near-surface waters, while day catches exceeded night catches at mid-depths. Sergestes similis migrated into the upper 50 m at night and on one occasion was collected at the surface. Title: Depth Distribution of Oceanic Shrimps (Decapoda ; Natantia) off Oregon Author: Forss, Carl A., Pearcy, William G. Sixteen species of oceanic shrimps, seven Penaeidea and nine Caridea, appeared in 244 collections made within the upper 1500 m at one station in the northeast Pacific off Oregon. Most of the species were primarily mesopelagic in distribution. The most abundant species, Sergestes similis, was the only shrimp common in epipelagic waters at night and the only species clearly demonstrating did vertical migrations. Night catches exceeded day catches in near-surface waters, while day catches exceeded night catches at mid-depths. Sergestes similis migrated into the upper 50 m at night and on one occasion was collected at the surface. Close

• 67. [Article] Waves and fractals

  The goal of this research project is to determine the fractal nature, if any, which surface water waves exhibit when viewed on a microscopic scale. Due to the relatively recent development of this area ...

  Citation × Citation Citation Abstract Copy Title: Waves and fractals Author: Gilliland, Crystal L. The goal of this research project is to determine the fractal nature, if any, which surface water waves exhibit when viewed on a microscopic scale. Due to the relatively recent development of this area of mathematics, a brief introduction to the study of fractal geometry, as well as several examples of fractals, are included in this paper. From that point, this paper addresses the specific situation of a surface wave as it nears the breaking point and attempts to detect the fractal structure of a wave at this given point when viewed on a microscopic scale. This is done from both a physical standpoint based on observations at the Hinsdale Wave Facility at Oregon State University and at Cape Perpetua, Oregon on the Pacific Coast, and from a theoretical standpoint based on a spring model. Title: Waves and fractals Author: Gilliland, Crystal L. The goal of this research project is to determine the fractal nature, if any, which surface water waves exhibit when viewed on a microscopic scale. Due to the relatively recent development of this area of mathematics, a brief introduction to the study of fractal geometry, as well as several examples of fractals, are included in this paper. From that point, this paper addresses the specific situation of a surface wave as it nears the breaking point and attempts to detect the fractal structure of a wave at this given point when viewed on a microscopic scale. This is done from both a physical standpoint based on observations at the Hinsdale Wave Facility at Oregon State University and at Cape Perpetua, Oregon on the Pacific Coast, and from a theoretical standpoint based on a spring model. Close

• 68. [Article] The changing carbon cycle in the Southern Ocean

  This is the publisher’s final pdf. The published article is copyrighted by The Oceanography Society and can be found at: www.tos.org/.

  Citation × Citation Citation Abstract Copy Title: The changing carbon cycle in the Southern Ocean Author: Takahashi, Taro, Newberger, Timothy, Goddard, John G., Chipman, David W., Sweeney, Colm, Hales, Burke, Sutherland, Stewart C., Iannuzzi, Richard A. This is the publisher’s final pdf. The published article is copyrighted by The Oceanography Society and can be found at: www.tos.org/. Title: The changing carbon cycle in the Southern Ocean Author: Takahashi, Taro, Newberger, Timothy, Goddard, John G., Chipman, David W., Sweeney, Colm, Hales, Burke, Sutherland, Stewart C., Iannuzzi, Richard A. This is the publisher’s final pdf. The published article is copyrighted by The Oceanography Society and can be found at: www.tos.org/. Close

• 69. [Article] Quantifying physical habitat in wadeable streams : surface waters

  We describe concepts, rationale, and analytical procedures for characterizing physical habitat in wadeable streams based on raw data generated from methods similar or equal to those of Kaufmann and Robison ...

  Citation × Citation Citation Abstract Copy Title: Quantifying physical habitat in wadeable streams : surface waters Author: Robison, E. George, Seeliger, Curt, Levine, Paul, Peck, David V., Kaufmann, Phillip R. We describe concepts, rationale, and analytical procedures for characterizing physical habitat in wadeable streams based on raw data generated from methods similar or equal to those of Kaufmann and Robison (in PB99-139156). We provide guidance for calculating measures or indices of stream size and gradient, sinuosity, substrate size and stability, habitat complexity and cover, woody debris size and abundance, residual pool dimensions and frequency, riparian vegetation cover and structure, anthropogenic disturbances, and channel-riparian interaction. We evaluated sampling precision of field habitat survey methods employed by EMAP in several hundred streams in Oregon and the Mid-Atlantic region, comparing variance among streams ('signals') with variance between repeat stream visits (measurement 'noise'). The final measure of the utility of a habitat approach is whether it is useful for interpreting controls on biota or impacts of human activity. Title: Quantifying physical habitat in wadeable streams : surface waters Author: Robison, E. George, Seeliger, Curt, Levine, Paul, Peck, David V., Kaufmann, Phillip R. We describe concepts, rationale, and analytical procedures for characterizing physical habitat in wadeable streams based on raw data generated from methods similar or equal to those of Kaufmann and Robison (in PB99-139156). We provide guidance for calculating measures or indices of stream size and gradient, sinuosity, substrate size and stability, habitat complexity and cover, woody debris size and abundance, residual pool dimensions and frequency, riparian vegetation cover and structure, anthropogenic disturbances, and channel-riparian interaction. We evaluated sampling precision of field habitat survey methods employed by EMAP in several hundred streams in Oregon and the Mid-Atlantic region, comparing variance among streams ('signals') with variance between repeat stream visits (measurement 'noise'). The final measure of the utility of a habitat approach is whether it is useful for interpreting controls on biota or impacts of human activity. Close

• 70. [Article] Cold halocline, increased nutrients and higher chlorophyll off Oregon in 2002

  Observed changes in the nutrient levels in the halocline of the California Current during 2002 indicated a natural eutrophication that was accompanied by increased chlorophyll and oxygen in surface water. ...

  Citation × Citation Citation Abstract Copy Title: Cold halocline, increased nutrients and higher chlorophyll off Oregon in 2002 Author: Wheeler, Patricia A., Huyer, Adriana, 1945-, Fleischbein, Jane Observed changes in the nutrient levels in the halocline of the California Current during 2002 indicated a natural eutrophication that was accompanied by increased chlorophyll and oxygen in surface water. Decreased oxygen in the lower water column over the shelf indicated that much of the phytoplankton production was respired rather than passed on to higher trophic levels. In 2002 the halocline water was >1ºC colder than usual and 0.5ºC colder than any previous observation. Four transect lines off the coast of Oregon show a 50% increase in nitrate, phosphate and silicate at 33 psu in 2002 compared to 1998–2001. The increase in nutrients resulted in a 2-fold increase in chlorophyll standing stocks during the summer of 2002 compared with the preceding four years. A significant portion of the increased production was subsequently respired resulting in low oxygen water over the shelf. Title: Cold halocline, increased nutrients and higher chlorophyll off Oregon in 2002 Author: Wheeler, Patricia A., Huyer, Adriana, 1945-, Fleischbein, Jane Observed changes in the nutrient levels in the halocline of the California Current during 2002 indicated a natural eutrophication that was accompanied by increased chlorophyll and oxygen in surface water. Decreased oxygen in the lower water column over the shelf indicated that much of the phytoplankton production was respired rather than passed on to higher trophic levels. In 2002 the halocline water was >1ºC colder than usual and 0.5ºC colder than any previous observation. Four transect lines off the coast of Oregon show a 50% increase in nitrate, phosphate and silicate at 33 psu in 2002 compared to 1998–2001. The increase in nutrients resulted in a 2-fold increase in chlorophyll standing stocks during the summer of 2002 compared with the preceding four years. A significant portion of the increased production was subsequently respired resulting in low oxygen water over the shelf. Close

• 71. [Article] A study of stream temperature using distributed temperature sensing fiber optics technology in Big Boulder Creek, a tributary to the Middle Fork John Day River in eastern Oregon

  Citation × Citation Citation Abstract Copy Title: A study of stream temperature using distributed temperature sensing fiber optics technology in Big Boulder Creek, a tributary to the Middle Fork John Day River in eastern Oregon Author: Arik, Aida D. Title: A study of stream temperature using distributed temperature sensing fiber optics technology in Big Boulder Creek, a tributary to the Middle Fork John Day River in eastern Oregon Author: Arik, Aida D. Close

• 72. [Article] A Collaborative Effort to Evaluate Water Resources in the Lower Siuslaw Watershed

  Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR.

  Citation × Citation Citation Abstract Copy Title: A Collaborative Effort to Evaluate Water Resources in the Lower Siuslaw Watershed Author: Livesay, Dave, Miller, Mike, Nelson, Dennis, Moellendorf, Suzanne Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Title: A Collaborative Effort to Evaluate Water Resources in the Lower Siuslaw Watershed Author: Livesay, Dave, Miller, Mike, Nelson, Dennis, Moellendorf, Suzanne Year: 2011 Presented at The Oregon Water Conference, May 24-25, 2011, Corvallis, OR. Close

• 73. [Article] Mixing and Intrusions in a Rotating Cold-Core Feature off Cape Blanco, Oregon

  During August 1986, a large cold anomaly was observed in satellite and in situ measurements near Cape Blanco at 42°N, 126°30′W off the Pacific Coast. Detailed vertical profiles of temperature, conductivity, ...

  Citation × Citation Citation Abstract Copy Title: Mixing and Intrusions in a Rotating Cold-Core Feature off Cape Blanco, Oregon Author: Caldwell, Douglas R., Stabeno, Phyllis J., Moum, James N. During August 1986, a large cold anomaly was observed in satellite and in situ measurements near Cape Blanco at 42°N, 126°30′W off the Pacific Coast. Detailed vertical profiles of temperature, conductivity, turbulent dissipation, and horizontal currents showed 1) surface water temperature changes as large as 2 degrees in 1 kilometer (but smaller gradients at depth); 2) a structure in the mean currents resembling that of either a cyclonic eddy or a current meander, 3) a current field in geostrophic balance on scales of 10 km and greater, 4) a region of intrusions on the northern side of the eddy; 5) a concentration of turbulence (as indicated by the kinetic-energy dissipation rate) on the edges of the eddy and in the region of intrusions, the core of the eddy being turbulence-free; and 6) a substantial change in the surface structure in 24 hours. Title: Mixing and Intrusions in a Rotating Cold-Core Feature off Cape Blanco, Oregon Author: Caldwell, Douglas R., Stabeno, Phyllis J., Moum, James N. During August 1986, a large cold anomaly was observed in satellite and in situ measurements near Cape Blanco at 42°N, 126°30′W off the Pacific Coast. Detailed vertical profiles of temperature, conductivity, turbulent dissipation, and horizontal currents showed 1) surface water temperature changes as large as 2 degrees in 1 kilometer (but smaller gradients at depth); 2) a structure in the mean currents resembling that of either a cyclonic eddy or a current meander, 3) a current field in geostrophic balance on scales of 10 km and greater, 4) a region of intrusions on the northern side of the eddy; 5) a concentration of turbulence (as indicated by the kinetic-energy dissipation rate) on the edges of the eddy and in the region of intrusions, the core of the eddy being turbulence-free; and 6) a substantial change in the surface structure in 24 hours. Close

• 74. [Article] Nutrient loading of surface waters in the Upper Klamath Basin : agricultural and natural sources

  Published March 2001. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog...

  Citation × Citation Citation Abstract Copy Title: Nutrient loading of surface waters in the Upper Klamath Basin : agricultural and natural sources Author: Charlton, Brian A., Oregon State University. Agricultural Experiment Station, Rykbost, K. A. Published March 2001. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Nutrient loading of surface waters in the Upper Klamath Basin : agricultural and natural sources Author: Charlton, Brian A., Oregon State University. Agricultural Experiment Station, Rykbost, K. A. Published March 2001. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 75. [Article] Fate and transport of the surfactant linear alkylbenzenesulfonate in a sewage-contaminated aquifer

  Linear alkylbenzenesulfonate (LAS) is the most widely used anionic surfactant in commercial detergent formulations. The environmental fate of LAS is of interest because of its disposal to wastewater treatment ...

  Citation × Citation Citation Abstract Copy Title: Fate and transport of the surfactant linear alkylbenzenesulfonate in a sewage-contaminated aquifer Author: Krueger, Carolyn J. Linear alkylbenzenesulfonate (LAS) is the most widely used anionic surfactant in commercial detergent formulations. The environmental fate of LAS is of interest because of its disposal to wastewater treatment facilities and subsequent occurrence as a micropollutant in surface waters and groundwater. While LAS fate in wastewater treatment systems and surface waters is well-documented, few studies describe LAS fate in groundwater. This work investigates the transport and biodegradation of LAS in sewage-contaminated groundwater using natural-gradient pulsed and continuous field tracer tests and laboratory column experiments. An "in-vial" disk elution technique that couples solid phase extraction disk elution of LAS as tetrabutylammonium ion pairs with injection-port derivatization was developed for the determination of LAS in groundwater. Pulsed tracer tests then were conducted in an aerobic (~9 mg/L dissolved oxygen) uncontaminated zone, and a moderately aerobic (~1 mg/L dissolved oxygen), sewage-contaminated zone. A continuous injection test also was conducted in the sewage-contaminated zone. Chromatographic separation of the surfactant mixture was observed and attributed to the greater retardation of the longer alkyl chain homologs during transport. In the sewage-contaminated groundwater, biodegradation preferentially removed the longer alkyl chain homologs and external isomers resulting in LAS mixtures that were enriched in the more mobile and biologically-resistant components. LAS mass removal coincided with a decrease in dissolved oxygen concentrations, the appearance of LAS metabolites, and an increase in the number of free-living bacteria. The composition of the LAS mixture changed in the continuous field and column experiments and biodegradation rates increased as dissolved oxygen concentration increased. Mass removal rates were generally 2-3 times greater in the column experiments than in the field for similar dissolved oxygen concentrations. Rate constants for the continuous and pulsed tests conducted in the field were comparable indicating that increased exposure time of the aquifer sediments to the LAS did not increase biodegradation rates. Title: Fate and transport of the surfactant linear alkylbenzenesulfonate in a sewage-contaminated aquifer Author: Krueger, Carolyn J. Linear alkylbenzenesulfonate (LAS) is the most widely used anionic surfactant in commercial detergent formulations. The environmental fate of LAS is of interest because of its disposal to wastewater treatment facilities and subsequent occurrence as a micropollutant in surface waters and groundwater. While LAS fate in wastewater treatment systems and surface waters is well-documented, few studies describe LAS fate in groundwater. This work investigates the transport and biodegradation of LAS in sewage-contaminated groundwater using natural-gradient pulsed and continuous field tracer tests and laboratory column experiments. An "in-vial" disk elution technique that couples solid phase extraction disk elution of LAS as tetrabutylammonium ion pairs with injection-port derivatization was developed for the determination of LAS in groundwater. Pulsed tracer tests then were conducted in an aerobic (~9 mg/L dissolved oxygen) uncontaminated zone, and a moderately aerobic (~1 mg/L dissolved oxygen), sewage-contaminated zone. A continuous injection test also was conducted in the sewage-contaminated zone. Chromatographic separation of the surfactant mixture was observed and attributed to the greater retardation of the longer alkyl chain homologs during transport. In the sewage-contaminated groundwater, biodegradation preferentially removed the longer alkyl chain homologs and external isomers resulting in LAS mixtures that were enriched in the more mobile and biologically-resistant components. LAS mass removal coincided with a decrease in dissolved oxygen concentrations, the appearance of LAS metabolites, and an increase in the number of free-living bacteria. The composition of the LAS mixture changed in the continuous field and column experiments and biodegradation rates increased as dissolved oxygen concentration increased. Mass removal rates were generally 2-3 times greater in the column experiments than in the field for similar dissolved oxygen concentrations. Rate constants for the continuous and pulsed tests conducted in the field were comparable indicating that increased exposure time of the aquifer sediments to the LAS did not increase biodegradation rates. Close

• 76. [Article] Understanding pesticide persistence and mobility for groundwater and surface water protection

  Published January 1994. Reprinted April 2007. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension...

  Citation × Citation Citation Abstract Copy Title: Understanding pesticide persistence and mobility for groundwater and surface water protection Author: Jenkins, Jeffrey J., Kerle, Elizabeth A., Oregon State University. Extension Service, Vogue, Peggy A. Published January 1994. Reprinted April 2007. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Understanding pesticide persistence and mobility for groundwater and surface water protection Author: Jenkins, Jeffrey J., Kerle, Elizabeth A., Oregon State University. Extension Service, Vogue, Peggy A. Published January 1994. Reprinted April 2007. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 77. [Article] Summary of a discussion : the relationships between land use and surface water phosphorus concentrations

  Published July 1997. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Summary of a discussion : the relationships between land use and surface water phosphorus concentrations Published July 1997. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Summary of a discussion : the relationships between land use and surface water phosphorus concentrations Published July 1997. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 78. [Article] Beaver ecology on the west Copper River Delta, Alaska

  Since the 1964 earthquake and geologic uplift, beavers (Castor canadensis) have expanded their historic range from the inland (outwash plain) Copper River Delta, Alaska to the once tidally influenced ...

  Citation × Citation Citation Abstract Copy Title: Beaver ecology on the west Copper River Delta, Alaska Author: Cooper, Erin E. Since the 1964 earthquake and geologic uplift, beavers (Castor canadensis) have expanded their historic range from the inland (outwash plain) Copper River Delta, Alaska to the once tidally influenced areas of the outer area (uplifted marsh). The uplift presents a unique opportunity to observe beaver expansion, habitat selection and influence on hydrologic structure of a coastal wetland ecosystem after a major disturbance. First, I examined the relationship between the sites of active beaver lodges and associated water and vegetative features (Chapter 2). I hypothesized that active lodge sites would be associated with distinct water features and woody vegetation types in each landscape. I used aerial photographic and ground survey methods to compare sightability and to determine habitat associations. I developed an a priori set of models to determine active beaver lodge occurrence using logistic regression with presence and absence as the response variables and water features and vegetation cover as the dependent variables. My results were similar between survey methods but differed between the two major landscape types. In the uplifted marsh, odds of an active lodge occurrance increased with the presence of former tidal sloughs and an increase in mixed shrub coverage. The odds of an active lodge occurrence increased with the presence of streams and decreased with increasing closed cottonwood-alder-willow coverage in the outwash plain. Post earthquake uplift, beaver now exploit a unique topographic setting through the use and modification of former tidal sloughs and a transitioning mixed shrub vegetation community. Second, I quantified the influence of beaver on the surface water of the West Copper River Delta using remote sensing (Chapter 3). Water features were documented from digitized aerial photographs from 1959, 1974, 1986, 1992/1993, and 1996. My results showed that surface water area in beaver influenced water impoundments increased from 0 to 20% from 1959 to 1996, concurrent with beaver colonization of the uplifted marsh. These results suggest that beavers may have altered the trajectory of wetland change on the West Copper River Delta by raising the water table within open water basins and flooding those areas that would have otherwise drained. Beaver may be used an effective management tool in wetland restoration where key habitat features are available. Title: Beaver ecology on the west Copper River Delta, Alaska Author: Cooper, Erin E. Since the 1964 earthquake and geologic uplift, beavers (Castor canadensis) have expanded their historic range from the inland (outwash plain) Copper River Delta, Alaska to the once tidally influenced areas of the outer area (uplifted marsh). The uplift presents a unique opportunity to observe beaver expansion, habitat selection and influence on hydrologic structure of a coastal wetland ecosystem after a major disturbance. First, I examined the relationship between the sites of active beaver lodges and associated water and vegetative features (Chapter 2). I hypothesized that active lodge sites would be associated with distinct water features and woody vegetation types in each landscape. I used aerial photographic and ground survey methods to compare sightability and to determine habitat associations. I developed an a priori set of models to determine active beaver lodge occurrence using logistic regression with presence and absence as the response variables and water features and vegetation cover as the dependent variables. My results were similar between survey methods but differed between the two major landscape types. In the uplifted marsh, odds of an active lodge occurrance increased with the presence of former tidal sloughs and an increase in mixed shrub coverage. The odds of an active lodge occurrence increased with the presence of streams and decreased with increasing closed cottonwood-alder-willow coverage in the outwash plain. Post earthquake uplift, beaver now exploit a unique topographic setting through the use and modification of former tidal sloughs and a transitioning mixed shrub vegetation community. Second, I quantified the influence of beaver on the surface water of the West Copper River Delta using remote sensing (Chapter 3). Water features were documented from digitized aerial photographs from 1959, 1974, 1986, 1992/1993, and 1996. My results showed that surface water area in beaver influenced water impoundments increased from 0 to 20% from 1959 to 1996, concurrent with beaver colonization of the uplifted marsh. These results suggest that beavers may have altered the trajectory of wetland change on the West Copper River Delta by raising the water table within open water basins and flooding those areas that would have otherwise drained. Beaver may be used an effective management tool in wetland restoration where key habitat features are available. Close

• 79. [Article] Dissolved nitrogen in surface waters and nitrogen mineralization in riparian soils within a multi-land use basin

  The growing population of Oregon’s Willamette River Basin places an increasing demand on the basin’s surface waters. Watershed-scale research addressing spatial trends of dissolved nitrogen (DN) and its ...

  Citation × Citation Citation Abstract Copy Title: Dissolved nitrogen in surface waters and nitrogen mineralization in riparian soils within a multi-land use basin Author: Evans, Daniel M. The growing population of Oregon’s Willamette River Basin places an increasing demand on the basin’s surface waters. Watershed-scale research addressing spatial trends of dissolved nitrogen (DN) and its relationship with landuse and soil N dynamics, such as N mineralization, is sparse in the Willamette Basin. I measured DN along 124 km of the Calapooia River, a tributary to the Willamette River, and in 44 non-nested sub-basins to the Calapooia River for three years. Relationships between land-use and DN concentrations were explored using correlation and regression analysis. Additionally, I measured net N mineralization at monthly intervals for one year in surface soils (0-15cm) of the riparian zone at 32 locations along the length of the Calapooia River. Results show that there was consistently more DN in lower sub-basin surface waters dominated by poorly drained soils and agricultural production when compared to upper sub-basins that are dominated by well-drained soils and timber production. Nitrate-N was >10 mg L-1 for eight lower-basins and total N was >10 mg L-1 for nine lower basins during at least one sample period. Dissolved organic N (DON) represented a greater proportion of DN in the upper basin, but had lower concentrations relative to the lower basin. Seasonal nitrate-N concentrations had strong positive correlations to the percent of a sub-basin that was managed for agriculture (%AG) in all seasons except summer, whereas seasonal DON concentrations had strong positive correlations to %AG in all seasons. This study indicated that DN concentrations and components varied widely among seasons and years relative to precipitation amount and timing, soil drainage, and land management. Efforts to reduce or regulate DN in the Calapooia Basin or similar basins in the Willamette Basin must address this large temporal variability and should include consideration of soil drainage because of its influence on hydrological connections between terrestrial and aquatic systems. Net N mineralization in riparian soils had seasonal trends with relatively low mean net mineralization rates in the fall and winter and relatively high mean rates in the spring and summer when conditions for microbial activity and decomposition were enhanced. Annual net N mineralization was positively correlated with total N and labile N in surface soils and with basal area of hardwoods within the riparian zone. Annual net N mineralization per unit area was lower in riparian soils along the upper reaches of the basin compared to the lower reaches. This difference was primarily caused by higher amounts of coarse fragments in soils along the upper reaches. This demonstrates that there is an inherent likelihood of more N mineralization in riparian soils of the lower Calapooia Basin because of a lack of coarse fragments when compared to the upper basin. Net N mineralization per kg of soil-size fraction may be a more appropriate measure when exploring relationships with riparian conditions on watershed scales. Title: Dissolved nitrogen in surface waters and nitrogen mineralization in riparian soils within a multi-land use basin Author: Evans, Daniel M. The growing population of Oregon’s Willamette River Basin places an increasing demand on the basin’s surface waters. Watershed-scale research addressing spatial trends of dissolved nitrogen (DN) and its relationship with landuse and soil N dynamics, such as N mineralization, is sparse in the Willamette Basin. I measured DN along 124 km of the Calapooia River, a tributary to the Willamette River, and in 44 non-nested sub-basins to the Calapooia River for three years. Relationships between land-use and DN concentrations were explored using correlation and regression analysis. Additionally, I measured net N mineralization at monthly intervals for one year in surface soils (0-15cm) of the riparian zone at 32 locations along the length of the Calapooia River. Results show that there was consistently more DN in lower sub-basin surface waters dominated by poorly drained soils and agricultural production when compared to upper sub-basins that are dominated by well-drained soils and timber production. Nitrate-N was >10 mg L-1 for eight lower-basins and total N was >10 mg L-1 for nine lower basins during at least one sample period. Dissolved organic N (DON) represented a greater proportion of DN in the upper basin, but had lower concentrations relative to the lower basin. Seasonal nitrate-N concentrations had strong positive correlations to the percent of a sub-basin that was managed for agriculture (%AG) in all seasons except summer, whereas seasonal DON concentrations had strong positive correlations to %AG in all seasons. This study indicated that DN concentrations and components varied widely among seasons and years relative to precipitation amount and timing, soil drainage, and land management. Efforts to reduce or regulate DN in the Calapooia Basin or similar basins in the Willamette Basin must address this large temporal variability and should include consideration of soil drainage because of its influence on hydrological connections between terrestrial and aquatic systems. Net N mineralization in riparian soils had seasonal trends with relatively low mean net mineralization rates in the fall and winter and relatively high mean rates in the spring and summer when conditions for microbial activity and decomposition were enhanced. Annual net N mineralization was positively correlated with total N and labile N in surface soils and with basal area of hardwoods within the riparian zone. Annual net N mineralization per unit area was lower in riparian soils along the upper reaches of the basin compared to the lower reaches. This difference was primarily caused by higher amounts of coarse fragments in soils along the upper reaches. This demonstrates that there is an inherent likelihood of more N mineralization in riparian soils of the lower Calapooia Basin because of a lack of coarse fragments when compared to the upper basin. Net N mineralization per kg of soil-size fraction may be a more appropriate measure when exploring relationships with riparian conditions on watershed scales. Close

• 80. [Article] Fiber optics opens window on stream dynamics

  This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/.

  Citation × Citation Citation Abstract Copy Title: Fiber optics opens window on stream dynamics Author: van de Giesen, Nick, Parlange, Marc B., Westhoff, Martijn, Selker, John, Luxemburg, Wim This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Title: Fiber optics opens window on stream dynamics Author: van de Giesen, Nick, Parlange, Marc B., Westhoff, Martijn, Selker, John, Luxemburg, Wim This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Close

• 81. [Article] A comparison of watershed contamination between a sewered and an unsewered community

  In 1968, a study conducted by the sanitarians of the State Health Division and Benton County Health Department revealed a high failure rate of on-site sewage disposal systems in Southwest Corvallis. The ...

  Citation × Citation Citation Abstract Copy Title: A comparison of watershed contamination between a sewered and an unsewered community Author: Maritim, Gabriel Kipngeno, 1950- In 1968, a study conducted by the sanitarians of the State Health Division and Benton County Health Department revealed a high failure rate of on-site sewage disposal systems in Southwest Corvallis. The survey team concluded that sewage disposal in this area was inadequate, and a significant health hazard existed due to contamination of the watershed. Following these findings, a part of Southwest Corvallis was annexed to the city of Corvallis and sewered. The rest of the community remained unsewered and continued to use on-site sewage disposal systems. This follow-up study, therefore, was designed to quantitatively determine and compare the bacteriological levels of watershed contamination in the sewered and the unsewered area. Specifically, this investigation was to determine if the replacement of on-site sewage disposal systems by municipal sewer service in the sewered area significantly reduced surface water contamination and subsequently eliminated the sewage related health hazards. Major hypotheses tested in this study were: Ho₁: µ[subscript 1968] bacteriological levels = µ[subscript 1979] bacteriological levels in the sewered area (i.e.: There is no significant difference between the mean bacteriological levels before and after municipal sewer connections.) Ho₂: u[subscript 1968] bacteriological levels = u[subscript 1979] bacteriological levels in the unsewered area (i.e.: There has been no significant change in bacteriological level in the unsewered area since 1968.) According to the 1968 investigating team, sampling sites were chosen within the guidelines of sampling procedures given in The Standards Methods for the Examination of Water and Wastewater. The current investigator closely followed the same guidelines, and since this was a comparative study, samples were obtained from the 22 sampling sites that were chosen in 1968 by previous investigators. From the findings of this study the following conclusions have been drawn. 1. The replacement of individual on-site sewage disposal systems with municipal sewage systems significantly reduced the level of surface water contamination. Subsequently, the sewage related health hazards has significantly diminished in the sewered areas. The null hypothesis was rejected at α = 0.01. 2. The levels of surface water contamination were still the same in the unsewered area. Thus, the sewage related health hazards still existed in the area. The null hypothesis was rejected at α = 0.01. The findings, therefore, strongly suggested that municipal sewer systems were more effective than the on-site sewage disposal systems in the area studied. Title: A comparison of watershed contamination between a sewered and an unsewered community Author: Maritim, Gabriel Kipngeno, 1950- In 1968, a study conducted by the sanitarians of the State Health Division and Benton County Health Department revealed a high failure rate of on-site sewage disposal systems in Southwest Corvallis. The survey team concluded that sewage disposal in this area was inadequate, and a significant health hazard existed due to contamination of the watershed. Following these findings, a part of Southwest Corvallis was annexed to the city of Corvallis and sewered. The rest of the community remained unsewered and continued to use on-site sewage disposal systems. This follow-up study, therefore, was designed to quantitatively determine and compare the bacteriological levels of watershed contamination in the sewered and the unsewered area. Specifically, this investigation was to determine if the replacement of on-site sewage disposal systems by municipal sewer service in the sewered area significantly reduced surface water contamination and subsequently eliminated the sewage related health hazards. Major hypotheses tested in this study were: Ho₁: µ[subscript 1968] bacteriological levels = µ[subscript 1979] bacteriological levels in the sewered area (i.e.: There is no significant difference between the mean bacteriological levels before and after municipal sewer connections.) Ho₂: u[subscript 1968] bacteriological levels = u[subscript 1979] bacteriological levels in the unsewered area (i.e.: There has been no significant change in bacteriological level in the unsewered area since 1968.) According to the 1968 investigating team, sampling sites were chosen within the guidelines of sampling procedures given in The Standards Methods for the Examination of Water and Wastewater. The current investigator closely followed the same guidelines, and since this was a comparative study, samples were obtained from the 22 sampling sites that were chosen in 1968 by previous investigators. From the findings of this study the following conclusions have been drawn. 1. The replacement of individual on-site sewage disposal systems with municipal sewage systems significantly reduced the level of surface water contamination. Subsequently, the sewage related health hazards has significantly diminished in the sewered areas. The null hypothesis was rejected at α = 0.01. 2. The levels of surface water contamination were still the same in the unsewered area. Thus, the sewage related health hazards still existed in the area. The null hypothesis was rejected at α = 0.01. The findings, therefore, strongly suggested that municipal sewer systems were more effective than the on-site sewage disposal systems in the area studied. Close

• 82. [Article] Sources and input mechanisms of hafnium and neodymium in surface waters of the Atlantic sector of the Southern Ocean

  This is the publisher’s final pdf. The article is sponsored by the Geochemical Society and the Meteoritical Society and published by Elsevier. It can be found at: http://www.journals.elsevier.com/geoch...

  Citation × Citation Citation Abstract Copy Title: Sources and input mechanisms of hafnium and neodymium in surface waters of the Atlantic sector of the Southern Ocean Author: Haley, Brian A., Stichel, Torben, Rickli, Jorg, Jeandel, Catherine, Pradoux, Catherine, Hathorne, Ed C., Frank, Martin This is the publisher’s final pdf. The article is sponsored by the Geochemical Society and the Meteoritical Society and published by Elsevier. It can be found at: http://www.journals.elsevier.com/geochimica-et-cosmochimica-acta. Title: Sources and input mechanisms of hafnium and neodymium in surface waters of the Atlantic sector of the Southern Ocean Author: Haley, Brian A., Stichel, Torben, Rickli, Jorg, Jeandel, Catherine, Pradoux, Catherine, Hathorne, Ed C., Frank, Martin This is the publisher’s final pdf. The article is sponsored by the Geochemical Society and the Meteoritical Society and published by Elsevier. It can be found at: http://www.journals.elsevier.com/geochimica-et-cosmochimica-acta. Close

• 83. [Article] Development and application of an analytical technique for the determination of methylmercury compounds in environmental samples based on isolation by distillation, followed by purge-and-trap sample concentration and GC/MS separation and detection, after aqueous phase ethylation with sodium tetraethylborate

  An analytical technique has been developed for the determination of methylmercury compounds in environmental samples. The technique is based on a two-stage procedure. In the first stage, methylmercury ...

  Citation × Citation Citation Abstract Copy Title: Development and application of an analytical technique for the determination of methylmercury compounds in environmental samples based on isolation by distillation, followed by purge-and-trap sample concentration and GC/MS separation and detection, after aqueous phase ethylation with sodium tetraethylborate Author: Rice, William R. An analytical technique has been developed for the determination of methylmercury compounds in environmental samples. The technique is based on a two-stage procedure. In the first stage, methylmercury compounds are isolated from the sample matrix as methylmercury chloride (MeRgCl) by distillation. The distillation procedure is based on a series of published methods for the determination of methylmercury compounds in sediment and natural waters. In the second stage, MeRgCl is converted to the more volatile methylethylmercury (MeRgEt) by derivatization with an aqueous solution of sodium tetraethylborate. The volatile species is then determined by purge-and-trap sample concentration and gas chromatography/mass spectrometry (GC/MS) separation and detection. Initial work focused on the development of the method with optimization of the experimental parameters and operating conditions associated with the distillation and final measurement steps. The concentration of MeHgCl in standard solutions (concentration range from 0-30 ng/L as Hg), with and without nitric acid preservation, was monitored as a function of storage time to evaluate storage losses. Aqueous solutions of MeHgCl at the ng/L level are very stable for at least three months if stored (1) in the dark at 4 DC, (2) in acid-cleaned polypropylene flasks, (3) and without nitric acid preservation. Rapid loss of MeHgCl was observed for solutions acidified with nitric acid and stored under identical conditions (25% and 40% decrease in signal response after 3 and 96 days, respectively). The analytical technique was applied to the determination of methylmercury compounds in lake-bottom sediment and surface-water samples collected from Cottage Grove Reservoir, located in Lane County, Oregon. The concentration of methylmercury in a surface-water sample was 2.1 ± 0.11 ng/L as Hg(II). Recoveries of approximately 100 percent were observed for surface-water samples spiked with MeHgCl to a level of 4 ng as Hg(II). Concentrations of methylmercury in lake-bottom sediment ranged from 0.143 ± 0.008 to 35 ± 3.1 ng/g sediment as Hg(II) (wet weight). Recoveries of approximately 90 percent were observed for sediment samples spiked with MeHgCl to a level of 15 ng as Hg(II). The reproducibility of the entire analytical technique and the measurement step alone were evaluated through the analysis of replicate sediment samples. The percent relative standard deviation (RSD) of the entire analytical procedure was 2.6 percent, while the percent RSD of the measurement step alone was determined to be 1.5 percent. The absolute detection limit for MeHgCl was determined to be 4 pg as Hg(II) for the analysis of a 40-mL sample volume. Title: Development and application of an analytical technique for the determination of methylmercury compounds in environmental samples based on isolation by distillation, followed by purge-and-trap sample concentration and GC/MS separation and detection, after aqueous phase ethylation with sodium tetraethylborate Author: Rice, William R. An analytical technique has been developed for the determination of methylmercury compounds in environmental samples. The technique is based on a two-stage procedure. In the first stage, methylmercury compounds are isolated from the sample matrix as methylmercury chloride (MeRgCl) by distillation. The distillation procedure is based on a series of published methods for the determination of methylmercury compounds in sediment and natural waters. In the second stage, MeRgCl is converted to the more volatile methylethylmercury (MeRgEt) by derivatization with an aqueous solution of sodium tetraethylborate. The volatile species is then determined by purge-and-trap sample concentration and gas chromatography/mass spectrometry (GC/MS) separation and detection. Initial work focused on the development of the method with optimization of the experimental parameters and operating conditions associated with the distillation and final measurement steps. The concentration of MeHgCl in standard solutions (concentration range from 0-30 ng/L as Hg), with and without nitric acid preservation, was monitored as a function of storage time to evaluate storage losses. Aqueous solutions of MeHgCl at the ng/L level are very stable for at least three months if stored (1) in the dark at 4 DC, (2) in acid-cleaned polypropylene flasks, (3) and without nitric acid preservation. Rapid loss of MeHgCl was observed for solutions acidified with nitric acid and stored under identical conditions (25% and 40% decrease in signal response after 3 and 96 days, respectively). The analytical technique was applied to the determination of methylmercury compounds in lake-bottom sediment and surface-water samples collected from Cottage Grove Reservoir, located in Lane County, Oregon. The concentration of methylmercury in a surface-water sample was 2.1 ± 0.11 ng/L as Hg(II). Recoveries of approximately 100 percent were observed for surface-water samples spiked with MeHgCl to a level of 4 ng as Hg(II). Concentrations of methylmercury in lake-bottom sediment ranged from 0.143 ± 0.008 to 35 ± 3.1 ng/g sediment as Hg(II) (wet weight). Recoveries of approximately 90 percent were observed for sediment samples spiked with MeHgCl to a level of 15 ng as Hg(II). The reproducibility of the entire analytical technique and the measurement step alone were evaluated through the analysis of replicate sediment samples. The percent relative standard deviation (RSD) of the entire analytical procedure was 2.6 percent, while the percent RSD of the measurement step alone was determined to be 1.5 percent. The absolute detection limit for MeHgCl was determined to be 4 pg as Hg(II) for the analysis of a 40-mL sample volume. Close

• 84. [Article] Seasonal spillover and varve formation in the Santa Barbara Basin, California

  A temporal record of oxygen and NO3- concentrations in the bottom water of the Santa Barbara Basin indicates that outside waters spill over into the basin seasonally. It is proposed that an annual bottom-water ...

  Citation × Citation Citation Abstract Copy Title: Seasonal spillover and varve formation in the Santa Barbara Basin, California Author: Reimers, Clare E., Tabak, Marialana, Lange, Carina B., Bernhard, Joan M. A temporal record of oxygen and NO3- concentrations in the bottom water of the Santa Barbara Basin indicates that outside waters spill over into the basin seasonally. It is proposed that an annual bottom-water cycle leads ultimately to varve production. As evidence in support of a benthic mechanism for varve formation, we present results of surface sediment and pore-water analyses, from box-core collections during three seasons in 1988. The greater degree of bottom-water oxygen depletion that occurs regularly in late summer and fall was coincident with a smaller pool of pore-water Fe, penetration of ΣH2S up to the sediment-water interface, maximal numbers of benthic Foraminifera, and bacterial mat growth. The latter was indicated by increases in concentrations of extractable ATP, organic C, and total N in sediments from the depth intervals 0–0.25 and 0.25–0.5 cm. The greatest numbers of siliceous phytoplankton skeletons were found on the sea floor soon after the late spring, surface-water, Chl a maximum. This event coincides with additions of new and more-oxygenated seawater to the deep basin. Title: Seasonal spillover and varve formation in the Santa Barbara Basin, California Author: Reimers, Clare E., Tabak, Marialana, Lange, Carina B., Bernhard, Joan M. A temporal record of oxygen and NO3- concentrations in the bottom water of the Santa Barbara Basin indicates that outside waters spill over into the basin seasonally. It is proposed that an annual bottom-water cycle leads ultimately to varve production. As evidence in support of a benthic mechanism for varve formation, we present results of surface sediment and pore-water analyses, from box-core collections during three seasons in 1988. The greater degree of bottom-water oxygen depletion that occurs regularly in late summer and fall was coincident with a smaller pool of pore-water Fe, penetration of ΣH2S up to the sediment-water interface, maximal numbers of benthic Foraminifera, and bacterial mat growth. The latter was indicated by increases in concentrations of extractable ATP, organic C, and total N in sediments from the depth intervals 0–0.25 and 0.25–0.5 cm. The greatest numbers of siliceous phytoplankton skeletons were found on the sea floor soon after the late spring, surface-water, Chl a maximum. This event coincides with additions of new and more-oxygenated seawater to the deep basin. Close

• 85. [Article] Temporal variation of hydrological exchange and hyporheic biogeochemistry in a headwater stream during autumn

  This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The North American Benthological Society and can be found at: http://www.freshwater-science.org/Journal.aspx. As ...

  Citation × Citation Citation Abstract Copy Title: Temporal variation of hydrological exchange and hyporheic biogeochemistry in a headwater stream during autumn Author: Ribot, Miquel, Marti, Eugenia, Sabater, Francesc, Argerich, Alba This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The North American Benthological Society and can be found at: http://www.freshwater-science.org/Journal.aspx. As of 2012, the Journal of the North American Benthological Society is called Freshwater Science and is published by The Society for Freshwater Science. Title: Temporal variation of hydrological exchange and hyporheic biogeochemistry in a headwater stream during autumn Author: Ribot, Miquel, Marti, Eugenia, Sabater, Francesc, Argerich, Alba This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by The North American Benthological Society and can be found at: http://www.freshwater-science.org/Journal.aspx. As of 2012, the Journal of the North American Benthological Society is called Freshwater Science and is published by The Society for Freshwater Science. Close

• 86. [Article] Spatial and temporal distribution of dissolved oxygen in Crater Lake, Oregon

  Small temporal and spatial variations in the distribution of dissolved oxygen in Crater Lake, Oregon, are used to estimate the mean age of the lake’s deep water, the flux of labile organic carbon to the ...

  Citation × Citation Citation Abstract Copy Title: Spatial and temporal distribution of dissolved oxygen in Crater Lake, Oregon Author: Dymond, Jack, Wheat, C. Geoffrey, McManus, James, Collier, Robert W., Larson, Gary L. Small temporal and spatial variations in the distribution of dissolved oxygen in Crater Lake, Oregon, are used to estimate the mean age of the lake’s deep water, the flux of labile organic carbon to the deep lake, and the influence of hydrothermal activity on the concentration of dissolved oxygen within the lake. An increase in the concentration of dissolved oxygen in the deep water during winter 1988-1989 indicates that 30-45% of deep water was replaced with well-oxygenated surface water. This deep-water renewal corresponds to a mean deep water residence time of 2-4 yr. The deep-water oxygen consumption rate is 2 l-26 μmol m-3 d-l, which occurs primarily through the oxidation of organic matter and, to a lesser extent, the oxidation of reduced inorganic species that are introduced to the lake via subsurface hydrothermal springs. Title: Spatial and temporal distribution of dissolved oxygen in Crater Lake, Oregon Author: Dymond, Jack, Wheat, C. Geoffrey, McManus, James, Collier, Robert W., Larson, Gary L. Small temporal and spatial variations in the distribution of dissolved oxygen in Crater Lake, Oregon, are used to estimate the mean age of the lake’s deep water, the flux of labile organic carbon to the deep lake, and the influence of hydrothermal activity on the concentration of dissolved oxygen within the lake. An increase in the concentration of dissolved oxygen in the deep water during winter 1988-1989 indicates that 30-45% of deep water was replaced with well-oxygenated surface water. This deep-water renewal corresponds to a mean deep water residence time of 2-4 yr. The deep-water oxygen consumption rate is 2 l-26 μmol m-3 d-l, which occurs primarily through the oxidation of organic matter and, to a lesser extent, the oxidation of reduced inorganic species that are introduced to the lake via subsurface hydrothermal springs. Close

• 87. [Article] Water scarcity and reservoir reliability in basins affected by climate and land use change : impacts of hydrogeology, sensitivities, and uncertainties in the Santiam River Basin, Oregon

  Multipurpose management of hydrosystems face a number of uncertainties related to hydrologic variability and nonstationarity. Anticipated air temperature increases in the Pacific Northwest region are projected ...

  Citation × Citation Citation Abstract Copy Title: Water scarcity and reservoir reliability in basins affected by climate and land use change : impacts of hydrogeology, sensitivities, and uncertainties in the Santiam River Basin, Oregon Author: Mateus, M. Cristina Multipurpose management of hydrosystems face a number of uncertainties related to hydrologic variability and nonstationarity. Anticipated air temperature increases in the Pacific Northwest region are projected to alter the timing and quantity of streamflow associated with precipitation shifting from snow to rain, including shorter winter runoff periods, earlier spring runoff, and longer and drier summers. Changes in land use, such as urbanization, can reduce infiltration and groundwater recharge, thus lowering base-flow levels. Furthermore, these future changes in water supply are likely to vary across catchments with sensitivity to climate and land use changes. In this dissertation, I investigate hydrosystem sensitivities to climate and land use change considering modeling uncertainty across two different hydrologic settings in the Santiam River Basin in Oregon (Chapter 2), the reliability of reservoirs to accommodate these changes given current operating procedures (Chapter 3), and the performance of alternative reservoir operations scenarios in mitigating projected future hydrologic changes (Chapter 4). This research is based on modeled future streamflows forced by temperature and precipitation projections from eight global climate models and two greenhouse gas emissions scenarios. To represent the uncertainty associated with future streamflow, I apply global climate model projections to a groundwater-surface water model (GSFLOW), coupled with a formal Bayesian uncertainty analysis. The land use changes were simulated in GSFLOW by adjusting model parameters based on the proportion of change in land use area within hydrologic response units. I apply streamflow projections as inputs to a reservoir operation model (HEC-ResSim) to analyze reservoir system reliability under future climate. I then use historical records to identify what outcomes are unacceptable to stakeholders, a condition labeled as vulnerable, and establish thresholds of reservoir reliability. I then use projections of future hydrology to identify the likelihood of the system being pushed to that vulnerable state under current and alternate reservoir operations. Modeling and analysis is conducted in the North and South Santiam River basin, Oregon. The North Santiam sub-basin is sourced by the High Cascades, with high elevations but low in relief, deep groundwater and spring-dominated drainage system that sustain base flow during the dry summer months. In contrast, the South Santiam sub-basin is entirely sourced by the Western Cascades geology, with steep drainage network and relatively impermeable rock that generates rapid runoff responses, high peak flows, high flow variability and little groundwater storage. In the context of water scarcity, Chapter 2 presents an analysis of the influence of climate and land use change on the future availability of water resources across sub-basins with different hydrogeological and land use characteristics. In this analysis, I investigate how sub-basin characteristics, including elevation, intensity of water demands, and apparent intensity of groundwater interactions, contribute to hydrologic sensitivity, to climate and land use change response, and to water scarcity. Across the entire SRB, water demand exerts the strongest influence on basin sensitivity to water scarcity, regardless of hydrogeology, with the highest demand located in the lower reaches dominated by agricultural and urban land uses. Results highlight how seasonal runoff responses to climate and land use change vary across sub-basins with differences in hydrogeology, land use, and elevation. In Chapter 3, I investigate the impact and importance of climate-related uncertainties and hydrologic variability on reliability and sensitivity of current reservoir operations for meeting water resources objectives. I assess whether and how projected future changes in the timing and quantity of water resources affect the reliability of reservoir systems to meet flood management, spring and summer environmental flows, and hydropower generation objectives. I evaluate which sub-basin and reservoir operations are more sensitive to hydrologic variability, and the sensitivity of different elements of reservoir operations to climate variability. Despite projected increases in winter flows and decreases in summer flows, results suggested little evidence of a response in reservoir operation performance to a warming climate, with the exception of summer flow targets in the SSB. Independent of climate impacts, historical prioritization of reservoir operations appeared to impact reliability, suggesting areas where operation performance may be improved. Results also highlighted how hydrologic uncertainty is likely to complicate planning for climate change in basins with substantial groundwater interactions. In Chapter 4, I apply a bottom-up approach to identify reservoir system sensitivities and vulnerabilities to changes in operations considering hydrologic variability and uncertainty. I compare historical reservoir reliability to projected future reliability to evaluate how well climate information can capture historical conditions that determine when the system is in a vulnerable state, and evaluate the effectiveness of implementing variable rule curves to current reservoir operations. Results highlight the poor fit between coupled GCM and hydrologic models and historical summer streamflows in this basin. Results illustrate how increases in air temperature appear to reduce the reliability of meeting summer flow targets, but have negligible impacts on reservoir refilling and flooding. Variable rule curves appear to mitigate the impact of atmospheric warming on summer target reliability to some extent, without compromising flood risk. Across the two hydrogeologic settings, results indicate that the mixed groundwater-surface water basin has higher sensitivity to changes in climate and reservoir operations than the basin with streamflows derived primarily from surface water. The studies presented herein provide useful information about the causes (e.g. climate change, land use change, water demands) and degree of future changes in the performance of hydrosystem, as well as the potential benefits of changes in reservoir operations. The results highlight several important conclusions. First, in addition to hydrogeology and elevation, considering water demands is a key mechanism needed to translate the analysis of atmospheric warming on low flows into the impacts on people. Second, the impact of climate variability on reservoir reliability was only evident for summer low flow targets. However, implementing variable rule curves to current reservoir operations appears to be an effective strategy to reduce the impact of atmospheric warming on summer target reliability, without increasing the risk of flooding. Finally, higher sensitivity to changes in climate and reservoir operations were projected for the mixed groundwater-surface water basin than the basin sourced primarily from surface water. Though, higher uncertainty is related with the basin with substantial groundwater interactions complicating the planning for climate change because water resources may be less predictable at these locations. While the results from this study are specific to the Santiam River Basin in Oregon, USA, the analyses and general findings regarding governing mechanisms for vulnerability to climate and land use change will be relevant to hydrosystems with similar hydrogeologic characteristics around the world. Title: Water scarcity and reservoir reliability in basins affected by climate and land use change : impacts of hydrogeology, sensitivities, and uncertainties in the Santiam River Basin, Oregon Author: Mateus, M. Cristina Multipurpose management of hydrosystems face a number of uncertainties related to hydrologic variability and nonstationarity. Anticipated air temperature increases in the Pacific Northwest region are projected to alter the timing and quantity of streamflow associated with precipitation shifting from snow to rain, including shorter winter runoff periods, earlier spring runoff, and longer and drier summers. Changes in land use, such as urbanization, can reduce infiltration and groundwater recharge, thus lowering base-flow levels. Furthermore, these future changes in water supply are likely to vary across catchments with sensitivity to climate and land use changes. In this dissertation, I investigate hydrosystem sensitivities to climate and land use change considering modeling uncertainty across two different hydrologic settings in the Santiam River Basin in Oregon (Chapter 2), the reliability of reservoirs to accommodate these changes given current operating procedures (Chapter 3), and the performance of alternative reservoir operations scenarios in mitigating projected future hydrologic changes (Chapter 4). This research is based on modeled future streamflows forced by temperature and precipitation projections from eight global climate models and two greenhouse gas emissions scenarios. To represent the uncertainty associated with future streamflow, I apply global climate model projections to a groundwater-surface water model (GSFLOW), coupled with a formal Bayesian uncertainty analysis. The land use changes were simulated in GSFLOW by adjusting model parameters based on the proportion of change in land use area within hydrologic response units. I apply streamflow projections as inputs to a reservoir operation model (HEC-ResSim) to analyze reservoir system reliability under future climate. I then use historical records to identify what outcomes are unacceptable to stakeholders, a condition labeled as vulnerable, and establish thresholds of reservoir reliability. I then use projections of future hydrology to identify the likelihood of the system being pushed to that vulnerable state under current and alternate reservoir operations. Modeling and analysis is conducted in the North and South Santiam River basin, Oregon. The North Santiam sub-basin is sourced by the High Cascades, with high elevations but low in relief, deep groundwater and spring-dominated drainage system that sustain base flow during the dry summer months. In contrast, the South Santiam sub-basin is entirely sourced by the Western Cascades geology, with steep drainage network and relatively impermeable rock that generates rapid runoff responses, high peak flows, high flow variability and little groundwater storage. In the context of water scarcity, Chapter 2 presents an analysis of the influence of climate and land use change on the future availability of water resources across sub-basins with different hydrogeological and land use characteristics. In this analysis, I investigate how sub-basin characteristics, including elevation, intensity of water demands, and apparent intensity of groundwater interactions, contribute to hydrologic sensitivity, to climate and land use change response, and to water scarcity. Across the entire SRB, water demand exerts the strongest influence on basin sensitivity to water scarcity, regardless of hydrogeology, with the highest demand located in the lower reaches dominated by agricultural and urban land uses. Results highlight how seasonal runoff responses to climate and land use change vary across sub-basins with differences in hydrogeology, land use, and elevation. In Chapter 3, I investigate the impact and importance of climate-related uncertainties and hydrologic variability on reliability and sensitivity of current reservoir operations for meeting water resources objectives. I assess whether and how projected future changes in the timing and quantity of water resources affect the reliability of reservoir systems to meet flood management, spring and summer environmental flows, and hydropower generation objectives. I evaluate which sub-basin and reservoir operations are more sensitive to hydrologic variability, and the sensitivity of different elements of reservoir operations to climate variability. Despite projected increases in winter flows and decreases in summer flows, results suggested little evidence of a response in reservoir operation performance to a warming climate, with the exception of summer flow targets in the SSB. Independent of climate impacts, historical prioritization of reservoir operations appeared to impact reliability, suggesting areas where operation performance may be improved. Results also highlighted how hydrologic uncertainty is likely to complicate planning for climate change in basins with substantial groundwater interactions. In Chapter 4, I apply a bottom-up approach to identify reservoir system sensitivities and vulnerabilities to changes in operations considering hydrologic variability and uncertainty. I compare historical reservoir reliability to projected future reliability to evaluate how well climate information can capture historical conditions that determine when the system is in a vulnerable state, and evaluate the effectiveness of implementing variable rule curves to current reservoir operations. Results highlight the poor fit between coupled GCM and hydrologic models and historical summer streamflows in this basin. Results illustrate how increases in air temperature appear to reduce the reliability of meeting summer flow targets, but have negligible impacts on reservoir refilling and flooding. Variable rule curves appear to mitigate the impact of atmospheric warming on summer target reliability to some extent, without compromising flood risk. Across the two hydrogeologic settings, results indicate that the mixed groundwater-surface water basin has higher sensitivity to changes in climate and reservoir operations than the basin with streamflows derived primarily from surface water. The studies presented herein provide useful information about the causes (e.g. climate change, land use change, water demands) and degree of future changes in the performance of hydrosystem, as well as the potential benefits of changes in reservoir operations. The results highlight several important conclusions. First, in addition to hydrogeology and elevation, considering water demands is a key mechanism needed to translate the analysis of atmospheric warming on low flows into the impacts on people. Second, the impact of climate variability on reservoir reliability was only evident for summer low flow targets. However, implementing variable rule curves to current reservoir operations appears to be an effective strategy to reduce the impact of atmospheric warming on summer target reliability, without increasing the risk of flooding. Finally, higher sensitivity to changes in climate and reservoir operations were projected for the mixed groundwater-surface water basin than the basin sourced primarily from surface water. Though, higher uncertainty is related with the basin with substantial groundwater interactions complicating the planning for climate change because water resources may be less predictable at these locations. While the results from this study are specific to the Santiam River Basin in Oregon, USA, the analyses and general findings regarding governing mechanisms for vulnerability to climate and land use change will be relevant to hydrosystems with similar hydrogeologic characteristics around the world. Close

• 88. [Article] An environmentally driven time-integrating water sampler

  This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/.

  Citation × Citation Citation Abstract Copy Title: An environmentally driven time-integrating water sampler Author: Rupp, David E., Selker, John S. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Title: An environmentally driven time-integrating water sampler Author: Rupp, David E., Selker, John S. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Close

• 89. [Article] Surface Water and Groundwater Interactions in the Walla Walla River, Northeast Oregon, USA : A Multi-Method Field-Based Approach

  Surface water and groundwater interactions are a key component in the functioning of stream ecosystems. Exchange of water between the stream and the hyporheic zone creates habitat for aquatic organisms ...

  Citation × Citation Citation Abstract Copy Title: Surface Water and Groundwater Interactions in the Walla Walla River, Northeast Oregon, USA : A Multi-Method Field-Based Approach Author: Gryczkowski, Landon Surface water and groundwater interactions are a key component in the functioning of stream ecosystems. Exchange of water between the stream and the hyporheic zone creates habitat for aquatic organisms and serves as a control for stream biogeochemical, thermal, and flow processes. This study takes a multi-method field-based approach to gain a better understanding of exchange processes in the Walla Walla River, Northeast Oregon, USA, with focus on advancing methodologies, spatial and temporal exchange dynamics, fish ecology and habitat, and geomorphic controls on hyporheic exchange. Fiber-optic distributed temperature sensing (DTS) was used to identify, quantify, and map cold-water inflows at the meter scale. Analysis of the maximum and minimum daily temperature traces separated each cold-water inflow into either hyporheic or groundwater-derived. DTS identified a very active hyporheic zone in this system, with a near-equal importance of hyporheic and groundwater inflows. Approximately one-third of the 2-km study reach was influence by cold-water inflows, providing significant cooling in certain areas. Using piezometers in conjunction with DTS provided validation and supplementation of DTS results, increased the reliability of conclusions, and helped to identify and understand specific exchange processes. Piezometer data showed downwelling conditions (negative head differential) except immediately downstream of riffles, with head differentials becoming increasingly negative farther downstream from a riffle. Furthermore, head differentials increased in the negative direction from left bank to right bank, indicating lateral movement of groundwater and more loss of river water from the right bank. Nearest to riffles and river bends, head differentials remained more stable over time, which may indicate that geomorphic structures influence head variations locally, while aquifer levels and dynamics have an increasing influence farther from these structures. Seasonally, head differentials became increasingly negative through the summer into fall as aquifer levels decreased, and areas of the river that lost the most water to the subsurface tended to lose more water at a faster rate as the summer progressed. However, the seasonal trend of head differentials may be counteracted by decreasing bed permeability, yielding little or no temporal change in vertical flux of water through the streambed. During high-flow events, river losses to the subsurface decreased overall; in particular, areas with the greatest water loss at low flows showed reduced losses during high flows. High variability and lack of patterns in the response to high flow events suggests complexity in this process. Temperature-related variables from DTS data were combined with habitat-related variables to determine which variables best explain pool-scale salmonid abundance. Two snorkel surveys of 23 pools within the study reach were performed. The change in temperature across the pool showed the strongest overall relationship to salmonid abundance, particularly Chinook salmon. Chinook salmon showed a stronger preference for specific pools compared to steelhead/rainbow trout. The magnitude of cold-water inflows appears more important than the presence or proportion of the pool receiving cold-water inflows, and salmonid abundance was more strongly explained by hyporheic inflows compared to groundwater. Temperature variables increased in importance relative to habitat variables in the second snorkel sample compared to sample one. The highest river temperatures of the summer occurred between the two sample dates, and this may suggest that salmonids’ affinity for cold-water refuge was enhanced through behavioral adaptation following periods of high temperature approaching the lethal threshold. The combined use of DTS, continuous electrical resistivity/induced polarization profiling, LiDAR, aerial imagery analysis, and field surveys allowed for the quantification of many geomorphic and hydraulic variables known or hypothesized to contribute to surface water and groundwater exchange processes. Regression analysis was used to determine which of these variables best explain the presence and magnitude of both groundwater and hyporheic inflows. For the first time, the cross-sectional area of the hyporheic zone was estimated at high resolution at the reach scale, and decreasing hyporheic cross-sectional area best explained both the presence and magnitude of cold-water inflows of either type. Higher water surface slope and sinuosity/curvature were next in order of importance. The presence of hyporheic inflows was also explained by higher water surface slope, sinuosity, and Reynolds number, while the magnitude of hyporheic inflows was best explained by higher sinuosity. Groundwater inflows were also explained by higher width-to-depth ratio, higher water surface slope, decreasing distance from a stream bank to the bankfull or floodplain extent, and decreasing flow velocity. Lateral processes (e.g. sinuosity) and vertical processes (e.g. water surface slope) were found to be of comparable importance, but lateral processes better explained larger decreases in stream temperature, possibly because lateral subsurface flow paths are longer in distance and duration. Hydraulic conductivity variables did not show up among the most important variables likely because of the difficulty in estimating hydraulic conductivity at the meter scale using electrical geophysical tools. Title: Surface Water and Groundwater Interactions in the Walla Walla River, Northeast Oregon, USA : A Multi-Method Field-Based Approach Author: Gryczkowski, Landon Surface water and groundwater interactions are a key component in the functioning of stream ecosystems. Exchange of water between the stream and the hyporheic zone creates habitat for aquatic organisms and serves as a control for stream biogeochemical, thermal, and flow processes. This study takes a multi-method field-based approach to gain a better understanding of exchange processes in the Walla Walla River, Northeast Oregon, USA, with focus on advancing methodologies, spatial and temporal exchange dynamics, fish ecology and habitat, and geomorphic controls on hyporheic exchange. Fiber-optic distributed temperature sensing (DTS) was used to identify, quantify, and map cold-water inflows at the meter scale. Analysis of the maximum and minimum daily temperature traces separated each cold-water inflow into either hyporheic or groundwater-derived. DTS identified a very active hyporheic zone in this system, with a near-equal importance of hyporheic and groundwater inflows. Approximately one-third of the 2-km study reach was influence by cold-water inflows, providing significant cooling in certain areas. Using piezometers in conjunction with DTS provided validation and supplementation of DTS results, increased the reliability of conclusions, and helped to identify and understand specific exchange processes. Piezometer data showed downwelling conditions (negative head differential) except immediately downstream of riffles, with head differentials becoming increasingly negative farther downstream from a riffle. Furthermore, head differentials increased in the negative direction from left bank to right bank, indicating lateral movement of groundwater and more loss of river water from the right bank. Nearest to riffles and river bends, head differentials remained more stable over time, which may indicate that geomorphic structures influence head variations locally, while aquifer levels and dynamics have an increasing influence farther from these structures. Seasonally, head differentials became increasingly negative through the summer into fall as aquifer levels decreased, and areas of the river that lost the most water to the subsurface tended to lose more water at a faster rate as the summer progressed. However, the seasonal trend of head differentials may be counteracted by decreasing bed permeability, yielding little or no temporal change in vertical flux of water through the streambed. During high-flow events, river losses to the subsurface decreased overall; in particular, areas with the greatest water loss at low flows showed reduced losses during high flows. High variability and lack of patterns in the response to high flow events suggests complexity in this process. Temperature-related variables from DTS data were combined with habitat-related variables to determine which variables best explain pool-scale salmonid abundance. Two snorkel surveys of 23 pools within the study reach were performed. The change in temperature across the pool showed the strongest overall relationship to salmonid abundance, particularly Chinook salmon. Chinook salmon showed a stronger preference for specific pools compared to steelhead/rainbow trout. The magnitude of cold-water inflows appears more important than the presence or proportion of the pool receiving cold-water inflows, and salmonid abundance was more strongly explained by hyporheic inflows compared to groundwater. Temperature variables increased in importance relative to habitat variables in the second snorkel sample compared to sample one. The highest river temperatures of the summer occurred between the two sample dates, and this may suggest that salmonids’ affinity for cold-water refuge was enhanced through behavioral adaptation following periods of high temperature approaching the lethal threshold. The combined use of DTS, continuous electrical resistivity/induced polarization profiling, LiDAR, aerial imagery analysis, and field surveys allowed for the quantification of many geomorphic and hydraulic variables known or hypothesized to contribute to surface water and groundwater exchange processes. Regression analysis was used to determine which of these variables best explain the presence and magnitude of both groundwater and hyporheic inflows. For the first time, the cross-sectional area of the hyporheic zone was estimated at high resolution at the reach scale, and decreasing hyporheic cross-sectional area best explained both the presence and magnitude of cold-water inflows of either type. Higher water surface slope and sinuosity/curvature were next in order of importance. The presence of hyporheic inflows was also explained by higher water surface slope, sinuosity, and Reynolds number, while the magnitude of hyporheic inflows was best explained by higher sinuosity. Groundwater inflows were also explained by higher width-to-depth ratio, higher water surface slope, decreasing distance from a stream bank to the bankfull or floodplain extent, and decreasing flow velocity. Lateral processes (e.g. sinuosity) and vertical processes (e.g. water surface slope) were found to be of comparable importance, but lateral processes better explained larger decreases in stream temperature, possibly because lateral subsurface flow paths are longer in distance and duration. Hydraulic conductivity variables did not show up among the most important variables likely because of the difficulty in estimating hydraulic conductivity at the meter scale using electrical geophysical tools. Close

• 90. [Article] Cenozoic biogenic silica sedimentation in the Antarctic Ocean, based on two deep sea drilling project sites

  The Antarctic Ocean during the Cenozoic experienced four periods of increased surface productivity: the Middle Eocene; the beginning of the Miocene; the Middle Miocene; and near the Miocene-Pliocene boundary. ...

  Citation × Citation Citation Abstract Copy Title: Cenozoic biogenic silica sedimentation in the Antarctic Ocean, based on two deep sea drilling project sites Author: Brewster, Nancy Ann The Antarctic Ocean during the Cenozoic experienced four periods of increased surface productivity: the Middle Eocene; the beginning of the Miocene; the Middle Miocene; and near the Miocene-Pliocene boundary. The fourth increase in productivity began five million years ago and has since progressively increased to the present level of intense surface productivity. The major control of Antarctic surface productivity is climate. Opal production in the Neogene increased during glacial times, due to the intensification of upwelling south of the Polar Front, caused from accelerated atmospheric circulation and an increased volume production of Antarctic Bottom Water. Cenozoic variations in surface productivity are also related to the tectonic changes in the Antarctic Ocean basin, which altered the patterns of surface and thermohaline circulation. Antarctic Surface Waters became more conducive to biological productivity with the progressive latitudinal and thermal isolation of Antarctica, The efficiency of surface productivity has progressed to such an extent that much of the global silica supply has been transferred to the Antarctic at the expense of other productive oceanic regions such as the Central Equatorial Pacific. In the Neogene, the preservation or dissolution of calcium carbonate is influenced by the rate of upwelling south of the Polar Front. During glacial times, the upwelling of COB_rich Circumpolar Deep Water accelerates and effectively raises the calcite compensation depth. Title: Cenozoic biogenic silica sedimentation in the Antarctic Ocean, based on two deep sea drilling project sites Author: Brewster, Nancy Ann The Antarctic Ocean during the Cenozoic experienced four periods of increased surface productivity: the Middle Eocene; the beginning of the Miocene; the Middle Miocene; and near the Miocene-Pliocene boundary. The fourth increase in productivity began five million years ago and has since progressively increased to the present level of intense surface productivity. The major control of Antarctic surface productivity is climate. Opal production in the Neogene increased during glacial times, due to the intensification of upwelling south of the Polar Front, caused from accelerated atmospheric circulation and an increased volume production of Antarctic Bottom Water. Cenozoic variations in surface productivity are also related to the tectonic changes in the Antarctic Ocean basin, which altered the patterns of surface and thermohaline circulation. Antarctic Surface Waters became more conducive to biological productivity with the progressive latitudinal and thermal isolation of Antarctica, The efficiency of surface productivity has progressed to such an extent that much of the global silica supply has been transferred to the Antarctic at the expense of other productive oceanic regions such as the Central Equatorial Pacific. In the Neogene, the preservation or dissolution of calcium carbonate is influenced by the rate of upwelling south of the Polar Front. During glacial times, the upwelling of COB_rich Circumpolar Deep Water accelerates and effectively raises the calcite compensation depth. Close

• 91. [Article] The Role of Wind-Generated Mixing in Coastal Upwelling

  A simple parameterization of mixing processes originally developed by Kraus and Turner (1967) is included in a two-dimensional, two-layer theory of wind-driven coastal upwelling. Mixed-layer deepening ...

  Citation × Citation Citation Abstract Copy Title: The Role of Wind-Generated Mixing in Coastal Upwelling Author: Richman, J. G., de Szoeke, R. A. A simple parameterization of mixing processes originally developed by Kraus and Turner (1967) is included in a two-dimensional, two-layer theory of wind-driven coastal upwelling. Mixed-layer deepening is a competition between entrainment due to wind stirring, stabilization due to surface beating, and upwelling vertical velocity. For longshore winds favorable to upwelling, the temperature of the surface water mass being pushed offshore by the wind is determined by that of the incoming subsurface water mass, by the surface heating, and by the mixing dynamics. An upwelling steady state is possible with surface heating. In this state, the vertical upwelling velocity is exactly matched by the entrainment velocity, and the resulting cold water flux into the mixed layer is balanced by surface heating; surface temperature increases linearly with distance offshore. Time-dependent numerical solutions exhibit a, tendency toward this steady-state solution. Winds favorable to downwelling cause detrainment of light water from the mixed layer into the quiescent lower layer, leading to conditions lacking any symmetry with those found for upwelling-favorable winds. This feature, observed in nature, is a consequence of the nonlinearity and irreversibility of the mixing processes in the theory. Computed model solutions for upwelling and downwelling bear reasonable resemblance to hydrographic observations made off Oregon during 1972 and 1973. Title: The Role of Wind-Generated Mixing in Coastal Upwelling Author: Richman, J. G., de Szoeke, R. A. A simple parameterization of mixing processes originally developed by Kraus and Turner (1967) is included in a two-dimensional, two-layer theory of wind-driven coastal upwelling. Mixed-layer deepening is a competition between entrainment due to wind stirring, stabilization due to surface beating, and upwelling vertical velocity. For longshore winds favorable to upwelling, the temperature of the surface water mass being pushed offshore by the wind is determined by that of the incoming subsurface water mass, by the surface heating, and by the mixing dynamics. An upwelling steady state is possible with surface heating. In this state, the vertical upwelling velocity is exactly matched by the entrainment velocity, and the resulting cold water flux into the mixed layer is balanced by surface heating; surface temperature increases linearly with distance offshore. Time-dependent numerical solutions exhibit a, tendency toward this steady-state solution. Winds favorable to downwelling cause detrainment of light water from the mixed layer into the quiescent lower layer, leading to conditions lacking any symmetry with those found for upwelling-favorable winds. This feature, observed in nature, is a consequence of the nonlinearity and irreversibility of the mixing processes in the theory. Computed model solutions for upwelling and downwelling bear reasonable resemblance to hydrographic observations made off Oregon during 1972 and 1973. Close

• 92. [Article] Late quaternary oceanic circulation along the Pacific Coast of South America

  The distribution patterns of quartz and opal contents and the distribution patterns of radiolarian assemblages, in the sediments of the southeastern Pacific, are largely controlled by both the surface ...

  Citation × Citation Citation Abstract Copy Title: Late quaternary oceanic circulation along the Pacific Coast of South America Author: Molina-Cruz, Adolfo The distribution patterns of quartz and opal contents and the distribution patterns of radiolarian assemblages, in the sediments of the southeastern Pacific, are largely controlled by both the surface winds and the mixed-layer oceanic circulation. The distribution pattern of quartz is related to eolian and ice-rafted transport, as well as to runoff. In the subtropical region, quartz distribution extends offshore of Peru as a tongue in the same direction and position as the prevailing trade winds. Along the South American and Antarctic coast, high quartz concentrations are found in patches near shore or abundances commonly decrease rapidly seaward. Opal distribution follows the mixed-layer circulation around the subtropical anticyclonic gyre and shows high values under areas of oceanic divergence, characterized by high primary productivity. Along the continental margins, opal abundances are diluted by terrigenous debris; even off the Peruvian coast, where strong upwelling occurs and consequently high primary productivity prevails The distribution patterns of six radiolarian assemblages, defined through Q-mode factor analysis, reflect the geographical distribution of water masses associated with both surface and subsurface circulation. These are: 1) the surface Antarctic water mass, 2) the surface Subantarctic-Temperate water mass, 3) the Chile Current, 4) the Peru Current, 5) the surface Subtropical water mass and 6) the Equatorial Undercurrent. The Equatorial Undercurrent surfaces either because of strong trade winds or because of considerable relaxed trade winds. The above mentioned distribution patterns have shifted geographically during the Late Quaternary because of global climatic changes (glacial and interglacial stages). Fluctuations in the strength of the winds have been concurrent with fluctuations in the amount of ice stored on the continents, represented by the δ18O stratigraphic record, however, the direction and position of the winds have varied in a rather complex manner. Consequently, the oceanic circulation and associated water masses have presented a different behavior within each of the last five δ18O stages. Approximately 127,000 years ago, at the δ18O stage 5/6 boundary, the oceanographic conditions along the Pacific coast of South America were like the ones observed presently. During δ18O stage 5, weak trade winds, probably less parallel to the Peruvian coast than at the present, caused reduction in coastal upwelling and allowed advection of subantarctic-temperate waters, via the Chi1 Current, along the Peruvian coast. During δ18O stage 4, the trade winds were strong and more parallel to the equator, even to the east of the Galapagos Islands This gave rise to surfacing of the Equatorial Undercurrent through divergence processes Because of weak trade winds, the Galapagos front was positioned nearer to the South American coast during the lower part of stage 3. During the upper δ18O stage 3 and stage 2, the Pacific coast of South America experienced an intensified circulation, a strong development of upwelling, and as a result "cool" surface water temperatures. Approximately 18,000 years ago, at the climax of the last glaciation (δ18O stage 2), sea surface temperatures in the subtropical southeastern Pacific, were as much as 4°C cooler than present during the austral winter. It appears that the trend to the present oceanographic conditions began first in high latitudes and later in the tropical regions. Similar features in oceanographic changes were also observed during the onset of δ18O stage 5. A significant waning of the Antarctic ice occurred approximately 400,000 years ago. This was preceded by a considerable waxing of the Antarctic ice close to the Brunhes-Matuyama paleo-magnetic boundary (approximately 700,000 years ago). During the last 700,000 years the Polar front zone has shifted from its present position toward the north. Title: Late quaternary oceanic circulation along the Pacific Coast of South America Author: Molina-Cruz, Adolfo The distribution patterns of quartz and opal contents and the distribution patterns of radiolarian assemblages, in the sediments of the southeastern Pacific, are largely controlled by both the surface winds and the mixed-layer oceanic circulation. The distribution pattern of quartz is related to eolian and ice-rafted transport, as well as to runoff. In the subtropical region, quartz distribution extends offshore of Peru as a tongue in the same direction and position as the prevailing trade winds. Along the South American and Antarctic coast, high quartz concentrations are found in patches near shore or abundances commonly decrease rapidly seaward. Opal distribution follows the mixed-layer circulation around the subtropical anticyclonic gyre and shows high values under areas of oceanic divergence, characterized by high primary productivity. Along the continental margins, opal abundances are diluted by terrigenous debris; even off the Peruvian coast, where strong upwelling occurs and consequently high primary productivity prevails The distribution patterns of six radiolarian assemblages, defined through Q-mode factor analysis, reflect the geographical distribution of water masses associated with both surface and subsurface circulation. These are: 1) the surface Antarctic water mass, 2) the surface Subantarctic-Temperate water mass, 3) the Chile Current, 4) the Peru Current, 5) the surface Subtropical water mass and 6) the Equatorial Undercurrent. The Equatorial Undercurrent surfaces either because of strong trade winds or because of considerable relaxed trade winds. The above mentioned distribution patterns have shifted geographically during the Late Quaternary because of global climatic changes (glacial and interglacial stages). Fluctuations in the strength of the winds have been concurrent with fluctuations in the amount of ice stored on the continents, represented by the δ18O stratigraphic record, however, the direction and position of the winds have varied in a rather complex manner. Consequently, the oceanic circulation and associated water masses have presented a different behavior within each of the last five δ18O stages. Approximately 127,000 years ago, at the δ18O stage 5/6 boundary, the oceanographic conditions along the Pacific coast of South America were like the ones observed presently. During δ18O stage 5, weak trade winds, probably less parallel to the Peruvian coast than at the present, caused reduction in coastal upwelling and allowed advection of subantarctic-temperate waters, via the Chi1 Current, along the Peruvian coast. During δ18O stage 4, the trade winds were strong and more parallel to the equator, even to the east of the Galapagos Islands This gave rise to surfacing of the Equatorial Undercurrent through divergence processes Because of weak trade winds, the Galapagos front was positioned nearer to the South American coast during the lower part of stage 3. During the upper δ18O stage 3 and stage 2, the Pacific coast of South America experienced an intensified circulation, a strong development of upwelling, and as a result "cool" surface water temperatures. Approximately 18,000 years ago, at the climax of the last glaciation (δ18O stage 2), sea surface temperatures in the subtropical southeastern Pacific, were as much as 4°C cooler than present during the austral winter. It appears that the trend to the present oceanographic conditions began first in high latitudes and later in the tropical regions. Similar features in oceanographic changes were also observed during the onset of δ18O stage 5. A significant waning of the Antarctic ice occurred approximately 400,000 years ago. This was preceded by a considerable waxing of the Antarctic ice close to the Brunhes-Matuyama paleo-magnetic boundary (approximately 700,000 years ago). During the last 700,000 years the Polar front zone has shifted from its present position toward the north. Close

• 93. [Article] Microbiological comparison of surface soil and unsaturated subsurface soil from a semiarid high desert

  Thirty-two chemoheterotrophic bacteria were isolated from unsaturated subsurface soil samples obtained from ca. 70 m below land surface in a high desert in southeastern Idaho. Most isolates were gram positive (84%) ...

  Citation × Citation Citation Abstract Copy Title: Microbiological comparison of surface soil and unsaturated subsurface soil from a semiarid high desert Author: Colwell, Frederick Thirty-two chemoheterotrophic bacteria were isolated from unsaturated subsurface soil samples obtained from ca. 70 m below land surface in a high desert in southeastern Idaho. Most isolates were gram positive (84%) and strict aerobes (79%). Acridine orange direct counts of microbes in one subsurface sample showed lower numbers than similar counts performed on surface soils from the same location (ca. 5 x 10⁵ versus 2 x 10⁶ cells per g [dry weight] of soil), but higher numbers than those from plate counts performed on the subsurface material. Another sample taken from the same depth at another location showed no evidence of colonies under identical conditions. Soil analyses indicated that subsurface sediments versus surface soils were slightly alkaline (pH 7.9 versus 7.4), had a higher water content (25.7 versus 6.3%), and had lower organic carbon concentrations (0.05 to 0.17 versus 0.25% of soil dry weight). Analyses of biologically relevant gases from the unsaturated subsurface indicated an aerobic environment. As in other unsaturated soil environments, either a high proportion of bacteria in these subsurface sediments are not viable or they are incapable of growth on conventional media under aerobic conditions. The presence and numbers of bacteria in these deep sediments may be influenced by colonization opportunities afforded by periodic percolation of surface water through fractures in overlying strata. Title: Microbiological comparison of surface soil and unsaturated subsurface soil from a semiarid high desert Author: Colwell, Frederick Thirty-two chemoheterotrophic bacteria were isolated from unsaturated subsurface soil samples obtained from ca. 70 m below land surface in a high desert in southeastern Idaho. Most isolates were gram positive (84%) and strict aerobes (79%). Acridine orange direct counts of microbes in one subsurface sample showed lower numbers than similar counts performed on surface soils from the same location (ca. 5 x 10⁵ versus 2 x 10⁶ cells per g [dry weight] of soil), but higher numbers than those from plate counts performed on the subsurface material. Another sample taken from the same depth at another location showed no evidence of colonies under identical conditions. Soil analyses indicated that subsurface sediments versus surface soils were slightly alkaline (pH 7.9 versus 7.4), had a higher water content (25.7 versus 6.3%), and had lower organic carbon concentrations (0.05 to 0.17 versus 0.25% of soil dry weight). Analyses of biologically relevant gases from the unsaturated subsurface indicated an aerobic environment. As in other unsaturated soil environments, either a high proportion of bacteria in these subsurface sediments are not viable or they are incapable of growth on conventional media under aerobic conditions. The presence and numbers of bacteria in these deep sediments may be influenced by colonization opportunities afforded by periodic percolation of surface water through fractures in overlying strata. Close

• 94. [Article] Consumptive use of surface water by Willamette Basin municipalities

  The consumptive water use of six cities in the Willamette Basin of northwestern Oregon was evaluated for the period 1960-66. Consumptive use ratios were obtained by analyzing data from monthly water supply ...

  Citation × Citation Citation Abstract Copy Title: Consumptive use of surface water by Willamette Basin municipalities Author: Mittelstadt, Richard Lee The consumptive water use of six cities in the Willamette Basin of northwestern Oregon was evaluated for the period 1960-66. Consumptive use ratios were obtained by analyzing data from monthly water supply and sewage flow records. The average annual consumptive use for the six cities was found to be 26 percent, and the average monthly ratios varied from essentially zero in the winter months to as high as 53 percent in July and August. The principal factors affecting consumptive use were found to be weather conditions, lawn watering, water system losses, cost of water, air conditioning, and proportion of water used for industrial purposes. While not affecting consumptive use, per se, sewer infiltration, storm runoff, and incomplete water or sewer systems can affect the calculated consumptive use ratios. The extent to which a water right is consumptive is inferred by the use to which the water is put. On the basis of existing water law and past court decisions, it is concluded that a city has the legal right to consume the full amount of its municipal water right providing the water is used strictly in accordance with the conditions of its permit. Title: Consumptive use of surface water by Willamette Basin municipalities Author: Mittelstadt, Richard Lee The consumptive water use of six cities in the Willamette Basin of northwestern Oregon was evaluated for the period 1960-66. Consumptive use ratios were obtained by analyzing data from monthly water supply and sewage flow records. The average annual consumptive use for the six cities was found to be 26 percent, and the average monthly ratios varied from essentially zero in the winter months to as high as 53 percent in July and August. The principal factors affecting consumptive use were found to be weather conditions, lawn watering, water system losses, cost of water, air conditioning, and proportion of water used for industrial purposes. While not affecting consumptive use, per se, sewer infiltration, storm runoff, and incomplete water or sewer systems can affect the calculated consumptive use ratios. The extent to which a water right is consumptive is inferred by the use to which the water is put. On the basis of existing water law and past court decisions, it is concluded that a city has the legal right to consume the full amount of its municipal water right providing the water is used strictly in accordance with the conditions of its permit. Close

• 95. [Article] Quantification of Osmolytes in the Sargasso Sea Surface Layer Water Column

  Oceanic carbon cycling plays a major role in determining global atmospheric CO₂. A better understanding of dissolved organic matter and its constituents in the water column and how it affects marine carbon ...

  Citation × Citation Citation Abstract Copy Title: Quantification of Osmolytes in the Sargasso Sea Surface Layer Water Column Author: Muslin, Omran Oceanic carbon cycling plays a major role in determining global atmospheric CO₂. A better understanding of dissolved organic matter and its constituents in the water column and how it affects marine carbon cycling is sought after. This study successfully measured osmolytes, low molecular zwitterionic compounds derived from amino acids, in depth profiles from the surface to 300 meters in the Sargasso Sea. Dimethylsulfionopropionate (DMSP), glycine betaine, and TMAo are three osmolytes that have been extensively studied. This study identified seven additional osmolytes in seawater for the first time: alanine betaine, propionobetaine, trigonelline, L-proline betaine, betonicine, butyrobetaine, and L-carnitine. We found that these compounds reached a maximum at different depths in the water column. Osmolyte concentrations were in the picomolar (pM) range, and fluctuated depending on time of day, suggesting a relationship to photosynthetic activity. Total osmolytes reached a maximum between 250 and 400 pM at the deep chlorophyll maximum at 80 to 120 meters below surface waters during all sampling times. In addition to these environmental measurements, experiments with cultured photosynthetic organisms were used to investigate the production of osmolytes in extracellular organic matter released by cells. These experiments yielded evidence of the production in culture of many of the osmolytes we had detected in seawater Title: Quantification of Osmolytes in the Sargasso Sea Surface Layer Water Column Author: Muslin, Omran Oceanic carbon cycling plays a major role in determining global atmospheric CO₂. A better understanding of dissolved organic matter and its constituents in the water column and how it affects marine carbon cycling is sought after. This study successfully measured osmolytes, low molecular zwitterionic compounds derived from amino acids, in depth profiles from the surface to 300 meters in the Sargasso Sea. Dimethylsulfionopropionate (DMSP), glycine betaine, and TMAo are three osmolytes that have been extensively studied. This study identified seven additional osmolytes in seawater for the first time: alanine betaine, propionobetaine, trigonelline, L-proline betaine, betonicine, butyrobetaine, and L-carnitine. We found that these compounds reached a maximum at different depths in the water column. Osmolyte concentrations were in the picomolar (pM) range, and fluctuated depending on time of day, suggesting a relationship to photosynthetic activity. Total osmolytes reached a maximum between 250 and 400 pM at the deep chlorophyll maximum at 80 to 120 meters below surface waters during all sampling times. In addition to these environmental measurements, experiments with cultured photosynthetic organisms were used to investigate the production of osmolytes in extracellular organic matter released by cells. These experiments yielded evidence of the production in culture of many of the osmolytes we had detected in seawater Close

• 96. [Article] Impact of land use patterns and agricultural practices on water quality in the Calapooia River Basin of western Oregon

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Soil and ...

  Citation × Citation Citation Abstract Copy Title: Impact of land use patterns and agricultural practices on water quality in the Calapooia River Basin of western Oregon Author: Giannico, G. R., Pfender, W.F., Whittaker, G.W., Garcia, T.S., Banowetz, G.M., Griffith, S.M., Mueller-Warrant, G.W. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Soil and Water Conservation Society and can be found at: http://www.jswconline.org/. Title: Impact of land use patterns and agricultural practices on water quality in the Calapooia River Basin of western Oregon Author: Giannico, G. R., Pfender, W.F., Whittaker, G.W., Garcia, T.S., Banowetz, G.M., Griffith, S.M., Mueller-Warrant, G.W. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Soil and Water Conservation Society and can be found at: http://www.jswconline.org/. Close

• 97. [Article] Input and cycling of iron in the Gulf of Aqaba, Red Sea

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Input and cycling of iron in the Gulf of Aqaba, Red Sea Author: Chen, Ying, Chase, Zanna, Johnson, Kenneth S., Paytan, Adina, Street, Joseph Copyrighted by American Geophysical Union. Title: Input and cycling of iron in the Gulf of Aqaba, Red Sea Author: Chen, Ying, Chase, Zanna, Johnson, Kenneth S., Paytan, Adina, Street, Joseph Copyrighted by American Geophysical Union. Close

• 98. [Article] Environmental temperature sensing using Raman spectra DTS fiber-optic methods

  This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/.

  Citation × Citation Citation Abstract Copy Title: Environmental temperature sensing using Raman spectra DTS fiber-optic methods Author: Torgersen, Thomas, Schladow, S. Geoffrey, Hausner, Mark B., Hatch, Christine E., Selker, John S., Tyler, Scott W., Thodal, Carl E. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Title: Environmental temperature sensing using Raman spectra DTS fiber-optic methods Author: Torgersen, Thomas, Schladow, S. Geoffrey, Hausner, Mark B., Hatch, Christine E., Selker, John S., Tyler, Scott W., Thodal, Carl E. This is the publisher’s final pdf. The published article is copyrighted by American Geophysical Union and can be found at: http://sites.agu.org/. Close

• 99. [Article] Phase 1: Benton County water analysis and demand forecast

  The Phase 1 report is an overview of the complex water quantity and quality information and issues specific to Benton County. It is a first step toward assessing and planning for future water quantity ...

  Citation × Citation Citation Abstract Copy Title: Phase 1: Benton County water analysis and demand forecast Author: Benton County Water Project The Phase 1 report is an overview of the complex water quantity and quality information and issues specific to Benton County. It is a first step toward assessing and planning for future water quantity and quality within Benton County and provides a template for regional water planning. The report details a collaborative process of data collection and assessment of the supply and demand (use) on surface water and groundwater resources. Forecasting is based on existing Federal, State and local databases. Baseline assessments of technical data related to water supply and demand were provided to an interdisciplinary steering committee and work teams tasked with providing direction and input. All committee and advisory team participation was voluntary. Engaging community stakeholders and residents was an important component of the project. Five community meetings and distribution of a questionnaire elicited concerns and values of county residents regarding water quantity and quality (Section 6). In addition, each steering committee and team meeting included an opportunity for public input where a number of water issues were identified. The Board of Benton County Commissioners is the convener of this project. The authority of the County Commissioners does not include regulation of water and is not binding upon the political jurisdictions within Benton County. Therefore, consensus is a goal. Title: Phase 1: Benton County water analysis and demand forecast Author: Benton County Water Project The Phase 1 report is an overview of the complex water quantity and quality information and issues specific to Benton County. It is a first step toward assessing and planning for future water quantity and quality within Benton County and provides a template for regional water planning. The report details a collaborative process of data collection and assessment of the supply and demand (use) on surface water and groundwater resources. Forecasting is based on existing Federal, State and local databases. Baseline assessments of technical data related to water supply and demand were provided to an interdisciplinary steering committee and work teams tasked with providing direction and input. All committee and advisory team participation was voluntary. Engaging community stakeholders and residents was an important component of the project. Five community meetings and distribution of a questionnaire elicited concerns and values of county residents regarding water quantity and quality (Section 6). In addition, each steering committee and team meeting included an opportunity for public input where a number of water issues were identified. The Board of Benton County Commissioners is the convener of this project. The authority of the County Commissioners does not include regulation of water and is not binding upon the political jurisdictions within Benton County. Therefore, consensus is a goal. Close

• 100. [Article] An update to the Surface Ocean CO₂ Atlas (SOCAT version 2)

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. This is the publisher’s final pdf. The published ...

  Citation × Citation Citation Abstract Copy Title: An update to the Surface Ocean CO₂ Atlas (SOCAT version 2) Author: Smith, K., Pfeil, B., et al., Hales, B., Bakker, D. C. E. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications and can be found at: http://www.earth-system-science-data.net/ Title: An update to the Surface Ocean CO₂ Atlas (SOCAT version 2) Author: Smith, K., Pfeil, B., et al., Hales, B., Bakker, D. C. E. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Copernicus Publications and can be found at: http://www.earth-system-science-data.net/ Close