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• 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