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• 151. [Article] An evaluation of planning for water quality control in the Willamette River Basin

  It is no longer possible in any area of the United States to formulate water resources plans for single purpose projects as has been done in past years. No longer can one of our greatest natural resources, water, ...

  Citation × Citation Citation Abstract Copy Title: An evaluation of planning for water quality control in the Willamette River Basin Author: Kirkpatrick, Kenton It is no longer possible in any area of the United States to formulate water resources plans for single purpose projects as has been done in past years. No longer can one of our greatest natural resources, water, be used solely for navigation, power generation, irrigation, or controlled for reducing floods. This resource must now serve a multitude of purposes in our society. Determining the present status of our water resources, what the future requirements will be, how to plan for these future needs, and implementation of these plans represents a major undertaking of local, State, and Federal authorities having interests in this field. In the Pacific Northwest, the Willamette Basin Task Force, acting under the auspices of the Columbia Basin Inter-Agency Committee, has been created to provide the coordinating mechanism for the prosecution of a comprehensive study for the management and development of the water and related land resources of the Willamette River Basin. This study is presently underway. In this thesis, information was collected from individuals associated with the Task Force, from minutes of meetings, and from other publications not readily available, to provide a single document giving the organization and objectives of the Task Force. The National comprehensive planning mechanism was studied to provide background information relating to the evolution of the Task Force and its operation. Water quality control is one of the areas of investigation of the Willamette Basin Task Force. It is directly related to and influenced by the several other multiple-purpose uses of the basin's water resources. It is this aspect of the comprehensive planning mechanism that has been considered in this thesis to evaluate what progress is being made in planning for present and future water quality control requirements for the basin. The results of this study indicate that additional study will be necessary, after further progress has been made by the Task Force, to fully evaluate the planning procedures and accomplishments of the Task Force. Conclusions indicate problems that have been encountered using this particular approach to water resources comprehensive planning. Various problems in the water pollution phase of the study are discussed. Several research study areas are suggested as a means of solving water quality problems which exist now in the Willamette River Basin and those water quality problems which are anticipated in the future as greater demands are placed on this resource. Title: An evaluation of planning for water quality control in the Willamette River Basin Author: Kirkpatrick, Kenton It is no longer possible in any area of the United States to formulate water resources plans for single purpose projects as has been done in past years. No longer can one of our greatest natural resources, water, be used solely for navigation, power generation, irrigation, or controlled for reducing floods. This resource must now serve a multitude of purposes in our society. Determining the present status of our water resources, what the future requirements will be, how to plan for these future needs, and implementation of these plans represents a major undertaking of local, State, and Federal authorities having interests in this field. In the Pacific Northwest, the Willamette Basin Task Force, acting under the auspices of the Columbia Basin Inter-Agency Committee, has been created to provide the coordinating mechanism for the prosecution of a comprehensive study for the management and development of the water and related land resources of the Willamette River Basin. This study is presently underway. In this thesis, information was collected from individuals associated with the Task Force, from minutes of meetings, and from other publications not readily available, to provide a single document giving the organization and objectives of the Task Force. The National comprehensive planning mechanism was studied to provide background information relating to the evolution of the Task Force and its operation. Water quality control is one of the areas of investigation of the Willamette Basin Task Force. It is directly related to and influenced by the several other multiple-purpose uses of the basin's water resources. It is this aspect of the comprehensive planning mechanism that has been considered in this thesis to evaluate what progress is being made in planning for present and future water quality control requirements for the basin. The results of this study indicate that additional study will be necessary, after further progress has been made by the Task Force, to fully evaluate the planning procedures and accomplishments of the Task Force. Conclusions indicate problems that have been encountered using this particular approach to water resources comprehensive planning. Various problems in the water pollution phase of the study are discussed. Several research study areas are suggested as a means of solving water quality problems which exist now in the Willamette River Basin and those water quality problems which are anticipated in the future as greater demands are placed on this resource. Close

• 152. [Article] Derivation of near-shore bathymetry from multispectral satellite imagery used in a coastal terrain model for the topographic analysis of human influence on coral reefs

  The analysis of material and energy exchange between the marine and terrestrial components of island ecosystems enables research into the impact of human population and land use on the health of coral ...

  Citation × Citation Citation Abstract Copy Title: Derivation of near-shore bathymetry from multispectral satellite imagery used in a coastal terrain model for the topographic analysis of human influence on coral reefs Author: Hogrefe, Kyle Richard The analysis of material and energy exchange between the marine and terrestrial components of island ecosystems enables research into the impact of human population and land use on the health of coral reef habitat. Satellite and acoustic remote sensing technologies enable the collection of data to produce high resolution bathymetry for integration with terrestrial digital elevation models (DEMs) into coastal terrain models. An integrated terrain surface that incorporates the land-sea interface, grounded by a geographic information system, is a powerful analytical tool for geomorphic studies of watersheds and coastal processes. The island of Tutuila, American Samoa is an ideal case study due to its high relief terrain, data availability and local interest in impacts to coral reef resources. The Tutuila model integrates a USGS DEM, multibeam bathymetry from 15 to 500 m and near shore bathymetric data from 0 to 15 m derived from IKONOS satellite imagery. The high spatial resolution of IKONOS imagery is suitable for detection of features with subtle relief and intricate structure. Shallow water bathymetry is derived by quantifying the relative attenuation of blue and green spectral band radiance as a function of depth. The procedure used to derive bathymetry, Lyzenga (1985), is identified as the most effective of several proposed in the recent literature. The product is error-checked using control points extracted from multibeam sonar data and collected during recent field surveys, as well as terrain profiles. The coastal terrain model provides morphological detail of fine resolution and high accuracy for terrain and land use analysis to enhance the study of ecosystem interconnectivity and the effects of anthropogenic inputs to coral reef habitats. Subsequent topographic analyses of the Tutuila model use drainage patterns to identify contiguous marine/terrestrial basins within which the marine environment is most directly impacted by land use through freshwater inputs from affiliated catchments. Human population density serves as an indicator of intensified land use and urbanization, which has been shown to increase pathogen and sediment loads in runoff, while percent coral cover, coral colony density and coral genera diversity are used as indicators of reef health. Spatiotemporal correlation analyses of population density against the three reef health indices within each of the marine/terrestrial basins reveal a decline in reef health associated with increased population density. This paper integrates and builds upon established methods of satellite imagery analysis and terrain modeling to create the Tutuila coastal terrain model and uses it to refine the scale of other studies linking human terrestrial activities to the physical condition of coral reefs. Title: Derivation of near-shore bathymetry from multispectral satellite imagery used in a coastal terrain model for the topographic analysis of human influence on coral reefs Author: Hogrefe, Kyle Richard The analysis of material and energy exchange between the marine and terrestrial components of island ecosystems enables research into the impact of human population and land use on the health of coral reef habitat. Satellite and acoustic remote sensing technologies enable the collection of data to produce high resolution bathymetry for integration with terrestrial digital elevation models (DEMs) into coastal terrain models. An integrated terrain surface that incorporates the land-sea interface, grounded by a geographic information system, is a powerful analytical tool for geomorphic studies of watersheds and coastal processes. The island of Tutuila, American Samoa is an ideal case study due to its high relief terrain, data availability and local interest in impacts to coral reef resources. The Tutuila model integrates a USGS DEM, multibeam bathymetry from 15 to 500 m and near shore bathymetric data from 0 to 15 m derived from IKONOS satellite imagery. The high spatial resolution of IKONOS imagery is suitable for detection of features with subtle relief and intricate structure. Shallow water bathymetry is derived by quantifying the relative attenuation of blue and green spectral band radiance as a function of depth. The procedure used to derive bathymetry, Lyzenga (1985), is identified as the most effective of several proposed in the recent literature. The product is error-checked using control points extracted from multibeam sonar data and collected during recent field surveys, as well as terrain profiles. The coastal terrain model provides morphological detail of fine resolution and high accuracy for terrain and land use analysis to enhance the study of ecosystem interconnectivity and the effects of anthropogenic inputs to coral reef habitats. Subsequent topographic analyses of the Tutuila model use drainage patterns to identify contiguous marine/terrestrial basins within which the marine environment is most directly impacted by land use through freshwater inputs from affiliated catchments. Human population density serves as an indicator of intensified land use and urbanization, which has been shown to increase pathogen and sediment loads in runoff, while percent coral cover, coral colony density and coral genera diversity are used as indicators of reef health. Spatiotemporal correlation analyses of population density against the three reef health indices within each of the marine/terrestrial basins reveal a decline in reef health associated with increased population density. This paper integrates and builds upon established methods of satellite imagery analysis and terrain modeling to create the Tutuila coastal terrain model and uses it to refine the scale of other studies linking human terrestrial activities to the physical condition of coral reefs. Close

• 153. [Article] Headwater stream characterization : an energy and physical approach to stream temperature using distributed temperature sensing

  Headwater streams are an integral part of the ecological health of the greater stream network as they provide valuable biological habitat, provide upwards to 95% of total in channel flow, while providing ...

  Citation × Citation Citation Abstract Copy Title: Headwater stream characterization : an energy and physical approach to stream temperature using distributed temperature sensing Author: Roth, Travis R. Headwater streams are an integral part of the ecological health of the greater stream network as they provide valuable biological habitat, provide upwards to 95% of total in channel flow, while providing downstream reaches with important constituents such as sediment and woody debris. Small headwater streams are particularly susceptible to anthropogenic and natural disturbances that affect their runoff production, chemical make-up, and thermal regime. Based on their position in the drainage basin and contribution to stream flow, heat energy transfer within a small mountain stream helps establish the thermal regime of the downstream lower order streams. However, headwater catchment thermal function remains poorly understood. Stream temperature is a manifestation of the environment through which it flows and the mechanisms by which it reaches the stream. Subsurface process controls, such as local soil properties, bedrock topography, and lateral flow discharge play an important role in headwater stream generation. Study outcomes are a result of vigorous field experimental work at the Watershed 07 (WS07) stream at the H.J. Andrews Experimental Forest (HJA) located in the Western Cascades, Oregon. Bedrock Topography was delineated through the use of a dynamic cone penetrometer, local lateral inflow sources were identified and quantified through the application of a salt tracer, and the energy budget was characterized through the use of Distributed Temperature Sensing (DTS) technology. High gradient, low volume streams such as WS07 provide unique challenges for DTS deployment which require extensive post-calibration data analysis. An automated cable submersion identification process was developed and was carried out on the collected temperature data with 32.8 % (379 of 1155) of measured temperature points identified as "in-water". Uncertainty propagation analysis associated with DTS measurement was calculated to be 0.21 °C. Salt tracer application found that 2 localized lateral inflow discharge to the stream accounted for 15% and 16% of total discharge in the upper section of the stream. Downstream lateral inflows exhibited incremental additions to stream discharge on the order of 5%. Stream discharge increased by 1.13 l/s from the upper section to the start of the lower section, an increase of 45%. Substantial lateral inflows provided reduction of stream temperatures in the lower section. Using DTS technology we measured stream temperature as a validation method for a physically based energy balance stream temperature model to characterize energy controls on stream temperature. Analysis of model performance was determined through root mean square error with reported values of 0.38 °C and 0.32 °C for the upper and lower section, respectively. Total energy inputs into the upper and lower sections of the stream were 302 W/m² and 210 W/m². Primary energy balance components were found to be solar radiation, atmospheric longwave radiation, and bed conduction. Solar radiation accounted for 63% of total energy flux into the stream in the upper section and 28% in the lower section. This is primarily a result of the distinct vegetation differences between the two reaches. Atmospheric longwave radiation contributed 27% and 26% of total energy flux in the upper and lower sections, respectively. While bed conduction made up 11% and 24% of the total flux in the upper and lower sections. Title: Headwater stream characterization : an energy and physical approach to stream temperature using distributed temperature sensing Author: Roth, Travis R. Headwater streams are an integral part of the ecological health of the greater stream network as they provide valuable biological habitat, provide upwards to 95% of total in channel flow, while providing downstream reaches with important constituents such as sediment and woody debris. Small headwater streams are particularly susceptible to anthropogenic and natural disturbances that affect their runoff production, chemical make-up, and thermal regime. Based on their position in the drainage basin and contribution to stream flow, heat energy transfer within a small mountain stream helps establish the thermal regime of the downstream lower order streams. However, headwater catchment thermal function remains poorly understood. Stream temperature is a manifestation of the environment through which it flows and the mechanisms by which it reaches the stream. Subsurface process controls, such as local soil properties, bedrock topography, and lateral flow discharge play an important role in headwater stream generation. Study outcomes are a result of vigorous field experimental work at the Watershed 07 (WS07) stream at the H.J. Andrews Experimental Forest (HJA) located in the Western Cascades, Oregon. Bedrock Topography was delineated through the use of a dynamic cone penetrometer, local lateral inflow sources were identified and quantified through the application of a salt tracer, and the energy budget was characterized through the use of Distributed Temperature Sensing (DTS) technology. High gradient, low volume streams such as WS07 provide unique challenges for DTS deployment which require extensive post-calibration data analysis. An automated cable submersion identification process was developed and was carried out on the collected temperature data with 32.8 % (379 of 1155) of measured temperature points identified as "in-water". Uncertainty propagation analysis associated with DTS measurement was calculated to be 0.21 °C. Salt tracer application found that 2 localized lateral inflow discharge to the stream accounted for 15% and 16% of total discharge in the upper section of the stream. Downstream lateral inflows exhibited incremental additions to stream discharge on the order of 5%. Stream discharge increased by 1.13 l/s from the upper section to the start of the lower section, an increase of 45%. Substantial lateral inflows provided reduction of stream temperatures in the lower section. Using DTS technology we measured stream temperature as a validation method for a physically based energy balance stream temperature model to characterize energy controls on stream temperature. Analysis of model performance was determined through root mean square error with reported values of 0.38 °C and 0.32 °C for the upper and lower section, respectively. Total energy inputs into the upper and lower sections of the stream were 302 W/m² and 210 W/m². Primary energy balance components were found to be solar radiation, atmospheric longwave radiation, and bed conduction. Solar radiation accounted for 63% of total energy flux into the stream in the upper section and 28% in the lower section. This is primarily a result of the distinct vegetation differences between the two reaches. Atmospheric longwave radiation contributed 27% and 26% of total energy flux in the upper and lower sections, respectively. While bed conduction made up 11% and 24% of the total flux in the upper and lower sections. Close

• 154. [Article] Subsurface geology of the southeastern Cuyama Valley, southern Coast Ranges, California

  The southeastern Cuyama Valley is located in the southern Coast Ranges, west of Bakersfield, California. Subsurface geologic mapping using data from 62 prospect wells was integrated with surface mapping to ...

  Citation × Citation Citation Abstract Copy Title: Subsurface geology of the southeastern Cuyama Valley, southern Coast Ranges, California Author: Spitz, Herbert M. The southeastern Cuyama Valley is located in the southern Coast Ranges, west of Bakersfield, California. Subsurface geologic mapping using data from 62 prospect wells was integrated with surface mapping to determine the depositional and deformational history of this part of the Neogene Cuyama basin. The northwest-trending Russell fault system was active from late Oligocene to Pliocene time. Deformation along this major wrench system began during deposition of the late Oligocene to early Miocene Soda Lake Shale Member of the Vaqueros Formation and ended prior to deposition of the Plio-Pleistocene Morales Formation. The southern extension of this fault system remains uncertain, but it probably joins the Ozena fault southeast of the South Cuyama oil field. Removal of 16 to 18 miles of right-lateral offset on the Russell fault system restores the Ozena fault to a position directly east of the La Panza fault. These two faults were probably a single fault, designated the La Panza-Ozena fault, which was active, north-side down, during the Oligocene. Nonmarine conglomerates of the Simmler and lower Caliente formations were deposited north of this fault during the Oligocene, prior to the initiation of notion on the Russell fault system. Three major faults of the Cox fault zone on the west and the Lundstrom-Becker and Becker-Heller faults on the east define the margins of the Cox trough, a complex north- to northeast-trending graben north of the Russell fault which was active from Saucesian through Relizian time (early Miocene). The Saltos Shale Member of the Monterey Formation increases in thickness by 3 to 7 times across the margins of the trough. Growth faulting associated with the Cox trough ended prior to deposition of the middle Johnston sand on all faults except the Cox 46-5 fault, which was active through deposition of the Branch Canyon Sandstone. Post-Pliocene tectonism in the Cuyama basin was limited to folding and reverse-faulting in response to regional north-south compression. The Central Cuyama dome and associated north-dipping reverse faults formed during an early episode of this deformation. Subsequent deformation occurred on the Morales fault, the South Cuyama fault, and the rejuvenated Ozena fault. This Quaternary thrusting obscured the structures of the older wrench-tectonic regime and resulted in the formation of the Caliente and Sierra Madre Ranges and the present-day Cuyama Valley. Title: Subsurface geology of the southeastern Cuyama Valley, southern Coast Ranges, California Author: Spitz, Herbert M. The southeastern Cuyama Valley is located in the southern Coast Ranges, west of Bakersfield, California. Subsurface geologic mapping using data from 62 prospect wells was integrated with surface mapping to determine the depositional and deformational history of this part of the Neogene Cuyama basin. The northwest-trending Russell fault system was active from late Oligocene to Pliocene time. Deformation along this major wrench system began during deposition of the late Oligocene to early Miocene Soda Lake Shale Member of the Vaqueros Formation and ended prior to deposition of the Plio-Pleistocene Morales Formation. The southern extension of this fault system remains uncertain, but it probably joins the Ozena fault southeast of the South Cuyama oil field. Removal of 16 to 18 miles of right-lateral offset on the Russell fault system restores the Ozena fault to a position directly east of the La Panza fault. These two faults were probably a single fault, designated the La Panza-Ozena fault, which was active, north-side down, during the Oligocene. Nonmarine conglomerates of the Simmler and lower Caliente formations were deposited north of this fault during the Oligocene, prior to the initiation of notion on the Russell fault system. Three major faults of the Cox fault zone on the west and the Lundstrom-Becker and Becker-Heller faults on the east define the margins of the Cox trough, a complex north- to northeast-trending graben north of the Russell fault which was active from Saucesian through Relizian time (early Miocene). The Saltos Shale Member of the Monterey Formation increases in thickness by 3 to 7 times across the margins of the trough. Growth faulting associated with the Cox trough ended prior to deposition of the middle Johnston sand on all faults except the Cox 46-5 fault, which was active through deposition of the Branch Canyon Sandstone. Post-Pliocene tectonism in the Cuyama basin was limited to folding and reverse-faulting in response to regional north-south compression. The Central Cuyama dome and associated north-dipping reverse faults formed during an early episode of this deformation. Subsequent deformation occurred on the Morales fault, the South Cuyama fault, and the rejuvenated Ozena fault. This Quaternary thrusting obscured the structures of the older wrench-tectonic regime and resulted in the formation of the Caliente and Sierra Madre Ranges and the present-day Cuyama Valley. Close

• 155. [Article] Historical change in channel form and riparian vegetation of the McKenzie River, Oregon

  This study examined channel structure and position and riparian vegetation and land use on the upper 70 km of the McKenzie River, Oregon in the 1940s, compared the 1940s conditions to present conditions, ...

  Citation × Citation Citation Abstract Copy Title: Historical change in channel form and riparian vegetation of the McKenzie River, Oregon Author: Minear, Paula J. This study examined channel structure and position and riparian vegetation and land use on the upper 70 km of the McKenzie River, Oregon in the 1940s, compared the 1940s conditions to present conditions, and explored the processes driving change in this system and the implications for aquatic habitat. The hydrologic record was analyzed, and field surveys were conducted and compared to historical habitat surveys. Riparian characteristics and channel features were digitized from aerial photographs from 1945/49 and 1986 and imported into Arcinfo GIS for analysis. Types of data digitized from the aerial photos included locations and length or area of wetted channel, active channel, tributaries, side channels, large woody debris, exposed gravel bars, roads, and dominant vegetation or land use within 200 m of the active channel. Construction of dams on the mainstem Mckenzie River and two major tributaries, Blue River and South Fork, in the 1960s has altered the flow regime and sediment supply to the mainstem Mckenzie, decreasing the frequency, mean and variation of peak flows, reducing the competence of flows to move existing bedload, and cutting off sediment from over half of the drainage area. Mean peak flows decreased 44% and competence of peak flows with a 2-yr recurrence interval declined approximately 29% after dams were constructed upriver. Adjustments to reduced sediment supply and flow alteration by dams in this system included 57% decrease in exposed gravel bars, 40% decrease in side channel length, and possible substrate coarsening (as compared to historical estimates). Channel straightening occurred in each of three instances of channel change during the study period, and sinuosity decreased one half of the amount needed to produce a straight channel in the most susceptible, unconstrained reach. Human actions prior to high flow events played a role in the direction of channel change in each case. Over the entire study area, 7% of the main channel changed position by 30 m or more and little or no change in channel position was noted in reaches constrained by valley floors. Additional channel constraint has been produced by road construction near the channel and riprapping for roads, bridges, and residences. Less large woody debris was observed in the 1986 channel than in the 1949 channel, indicating a reduction in pool-forming agents and channel roughness elements. Frequency of large pools ([greater than or equal to] 2 m depth and >40 m² area) decreased 19% over the study area. The greatest loss in pools (73%) was noted in the unconstrained reach that exhibited two areas of channel change and an increase in exposed gravel bars. Increased human use of the riparian area for roads and residential purposes has led to an increased fragmentation of the riparian landscape. Density of residential or developed patches within the riparian area has increased 215% as more and smaller areas are converted from natural vegetation to human use. Riparian area devoted to roads and residential uses has nearly doubled since the 1940s. Mean vegetation or land-use patch size has decreased from 2.2 ha to 1.6 ha as larger patches have been sub-divided, and patch and edge densities have increased. Agriculture and clearcuts for timber removal have decreased within the riparian area while continuing upslope. Riparian area in mature conifers has decreased 44% from levels in the 1940s while hardwoods have increased 45% in the riparian area. Future wood loading to the channel is reduced by a decline in mature riparian vegetation, especially mature conifers. Channel and riparian changes noted in this study have implications for fish populations. Channel straightening, reduction in side channels, and loss of pool-forming agents reduce habitat heterogeneity and off-channel refugia. Ecosystem management of watersheds requires evaluation of conditions across scales of time and space. The use of GIS in this study made it possible to detect changes in channel form and riparian conditions during four decades, along a 70-m channel and 90-m riparian area and to analyze the large data sets relevant to understanding functions and change in channels and riparian areas. Title: Historical change in channel form and riparian vegetation of the McKenzie River, Oregon Author: Minear, Paula J. This study examined channel structure and position and riparian vegetation and land use on the upper 70 km of the McKenzie River, Oregon in the 1940s, compared the 1940s conditions to present conditions, and explored the processes driving change in this system and the implications for aquatic habitat. The hydrologic record was analyzed, and field surveys were conducted and compared to historical habitat surveys. Riparian characteristics and channel features were digitized from aerial photographs from 1945/49 and 1986 and imported into Arcinfo GIS for analysis. Types of data digitized from the aerial photos included locations and length or area of wetted channel, active channel, tributaries, side channels, large woody debris, exposed gravel bars, roads, and dominant vegetation or land use within 200 m of the active channel. Construction of dams on the mainstem Mckenzie River and two major tributaries, Blue River and South Fork, in the 1960s has altered the flow regime and sediment supply to the mainstem Mckenzie, decreasing the frequency, mean and variation of peak flows, reducing the competence of flows to move existing bedload, and cutting off sediment from over half of the drainage area. Mean peak flows decreased 44% and competence of peak flows with a 2-yr recurrence interval declined approximately 29% after dams were constructed upriver. Adjustments to reduced sediment supply and flow alteration by dams in this system included 57% decrease in exposed gravel bars, 40% decrease in side channel length, and possible substrate coarsening (as compared to historical estimates). Channel straightening occurred in each of three instances of channel change during the study period, and sinuosity decreased one half of the amount needed to produce a straight channel in the most susceptible, unconstrained reach. Human actions prior to high flow events played a role in the direction of channel change in each case. Over the entire study area, 7% of the main channel changed position by 30 m or more and little or no change in channel position was noted in reaches constrained by valley floors. Additional channel constraint has been produced by road construction near the channel and riprapping for roads, bridges, and residences. Less large woody debris was observed in the 1986 channel than in the 1949 channel, indicating a reduction in pool-forming agents and channel roughness elements. Frequency of large pools ([greater than or equal to] 2 m depth and >40 m² area) decreased 19% over the study area. The greatest loss in pools (73%) was noted in the unconstrained reach that exhibited two areas of channel change and an increase in exposed gravel bars. Increased human use of the riparian area for roads and residential purposes has led to an increased fragmentation of the riparian landscape. Density of residential or developed patches within the riparian area has increased 215% as more and smaller areas are converted from natural vegetation to human use. Riparian area devoted to roads and residential uses has nearly doubled since the 1940s. Mean vegetation or land-use patch size has decreased from 2.2 ha to 1.6 ha as larger patches have been sub-divided, and patch and edge densities have increased. Agriculture and clearcuts for timber removal have decreased within the riparian area while continuing upslope. Riparian area in mature conifers has decreased 44% from levels in the 1940s while hardwoods have increased 45% in the riparian area. Future wood loading to the channel is reduced by a decline in mature riparian vegetation, especially mature conifers. Channel and riparian changes noted in this study have implications for fish populations. Channel straightening, reduction in side channels, and loss of pool-forming agents reduce habitat heterogeneity and off-channel refugia. Ecosystem management of watersheds requires evaluation of conditions across scales of time and space. The use of GIS in this study made it possible to detect changes in channel form and riparian conditions during four decades, along a 70-m channel and 90-m riparian area and to analyze the large data sets relevant to understanding functions and change in channels and riparian areas. Close

• 156. [Article] Forest Fire Effects on Radiative and Turbulent Fluxes over Snow : Implications for Snow Hydrology

  As a result of a warming climate, subsequent declining snowpack, and a century of fire suppression, forest fires are increasing across the western United States. However, we still do not fully understand ...

  Citation × Citation Citation Abstract Copy Title: Forest Fire Effects on Radiative and Turbulent Fluxes over Snow : Implications for Snow Hydrology Author: Gleason, Kelly Erika As a result of a warming climate, subsequent declining snowpack, and a century of fire suppression, forest fires are increasing across the western United States. However, we still do not fully understand how forest fire effects snowpack energy balance, nor the volume and availability of snow melt and associated water resources. This dissertation investigated the radiative and turbulent energy fluxes over snow in a burned and unburned forest site using a suite of experimental, modeling, and remote sensing methods to determine the overall impact of forest fire disturbance to snowpack energy balance and snow hydrology. For three years following the Shadow Lake Fire, which occurred in September 2011 at the crest of the Oregon Cascades, a suite of field experiments were maintained, including snow water equivalent and snow spectral albedo measurement transects, snow surface sampling, snow depth and basic micro-meteorological monitoring and eddy covariance measurements of turbulent heat fluxes. These data were used to empirically characterize forest fire effects to the radiative and turbulent fluxes over snow, to parameterize key drivers of snowpack energy balance and to model forest fire effects to snow hydrology using a physically-based spatially distributed snowpack energy and mass balance model for both the burned and unburned forest sites. This resulted in three papers summarizing forest fire effects to snowpack energy balance and implications for snow hydrology. This dissertation documented forest fire effects to the radiative and turbulent fluxes over snow and evaluated implications for snow hydrology. These results showed a 40% reduction in snow albedo in the burned forest during the ablation period in the first year following fire, while 60% more solar radiation reached the snow surface, driving a 200% increase in net shortwave radiation. This dissertation documented that both sensible and latent heat fluxes were double the magnitude and variability in the burned forest compared to the nearby unburned forest. These results showed that the turbulent fluxes over snow can be periodically large and substantial over time. The contribution of sensible heat flux and loss of energy by the latent heat flux is responsible for a loss of snow mass of approximately 2% that measured snowmelt in the burned forest site during the clear-sky snowmelt period. Overall, the radiative fluxes dominate the overall snowpack energy balance in burned and unburned forests. An empirically-based parameterization was developed to represent the temporal and spatial variability of snow albedo relative to days-since-snowfall in the burned and unburned forests, which was employed in a physically based spatially distributed snowpack energy and mass balance model. Using this variable snow albedo parameterization improved model performance in both burned and unburned forest sites, and better captured the temporal and spatial variability of snow albedo and snow water equivalent than a fixed albedo parameterization. Overall this evaluation demonstrated that even though more snow may accumulate in burned areas than unburned forests, the combined effect of the increased postfire radiative forcing to snow and increased turbulent fluxes over snow accelerates snow melt, shortens the duration of snow cover, and advances the date of snow disappearance across the extent of the burned forest. Although this research focused on a relatively small burned area in the western Oregon Cascades, it has broad applications from regional to global scales particularly in forested maritime snow-dominated watersheds. Eighty percent of forest fires in the western United States occur in the seasonal snow zone, and those fires are 4.4 times larger than outside the seasonal snow zone. As forest fires increase and snowpacks decrease across forested montane headwater regions of the western US and beyond, it is critical that we incorporate forest fire disturbance effects to snow hydrology in our hydrologic modeling applications and our natural resource management decisions. Title: Forest Fire Effects on Radiative and Turbulent Fluxes over Snow : Implications for Snow Hydrology Author: Gleason, Kelly Erika As a result of a warming climate, subsequent declining snowpack, and a century of fire suppression, forest fires are increasing across the western United States. However, we still do not fully understand how forest fire effects snowpack energy balance, nor the volume and availability of snow melt and associated water resources. This dissertation investigated the radiative and turbulent energy fluxes over snow in a burned and unburned forest site using a suite of experimental, modeling, and remote sensing methods to determine the overall impact of forest fire disturbance to snowpack energy balance and snow hydrology. For three years following the Shadow Lake Fire, which occurred in September 2011 at the crest of the Oregon Cascades, a suite of field experiments were maintained, including snow water equivalent and snow spectral albedo measurement transects, snow surface sampling, snow depth and basic micro-meteorological monitoring and eddy covariance measurements of turbulent heat fluxes. These data were used to empirically characterize forest fire effects to the radiative and turbulent fluxes over snow, to parameterize key drivers of snowpack energy balance and to model forest fire effects to snow hydrology using a physically-based spatially distributed snowpack energy and mass balance model for both the burned and unburned forest sites. This resulted in three papers summarizing forest fire effects to snowpack energy balance and implications for snow hydrology. This dissertation documented forest fire effects to the radiative and turbulent fluxes over snow and evaluated implications for snow hydrology. These results showed a 40% reduction in snow albedo in the burned forest during the ablation period in the first year following fire, while 60% more solar radiation reached the snow surface, driving a 200% increase in net shortwave radiation. This dissertation documented that both sensible and latent heat fluxes were double the magnitude and variability in the burned forest compared to the nearby unburned forest. These results showed that the turbulent fluxes over snow can be periodically large and substantial over time. The contribution of sensible heat flux and loss of energy by the latent heat flux is responsible for a loss of snow mass of approximately 2% that measured snowmelt in the burned forest site during the clear-sky snowmelt period. Overall, the radiative fluxes dominate the overall snowpack energy balance in burned and unburned forests. An empirically-based parameterization was developed to represent the temporal and spatial variability of snow albedo relative to days-since-snowfall in the burned and unburned forests, which was employed in a physically based spatially distributed snowpack energy and mass balance model. Using this variable snow albedo parameterization improved model performance in both burned and unburned forest sites, and better captured the temporal and spatial variability of snow albedo and snow water equivalent than a fixed albedo parameterization. Overall this evaluation demonstrated that even though more snow may accumulate in burned areas than unburned forests, the combined effect of the increased postfire radiative forcing to snow and increased turbulent fluxes over snow accelerates snow melt, shortens the duration of snow cover, and advances the date of snow disappearance across the extent of the burned forest. Although this research focused on a relatively small burned area in the western Oregon Cascades, it has broad applications from regional to global scales particularly in forested maritime snow-dominated watersheds. Eighty percent of forest fires in the western United States occur in the seasonal snow zone, and those fires are 4.4 times larger than outside the seasonal snow zone. As forest fires increase and snowpacks decrease across forested montane headwater regions of the western US and beyond, it is critical that we incorporate forest fire disturbance effects to snow hydrology in our hydrologic modeling applications and our natural resource management decisions. Close

• 157. [Article] Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data

  Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, ...

  Citation × Citation Citation Abstract Copy Title: Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data Author: Buffington, Kevin John Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, new methods are required that integrate data from the field and remote sensing platforms. Marsh elevation response models can be calibrated with site-specific data to determine the vulnerability of a marsh to sea-level rise and help guide management decisions. Elevation models are sensitive to initial elevation, the rate of accretion, and aboveground biomass. The overarching goal of this dissertation was to develop techniques to improve these important model inputs and evaluate the range of spatial and temporal variation. Light detection and ranging (lidar) is an invaluable tool for collecting elevation data, however dense vegetation prevents the accurate measurement of the tidal marsh surface. In Chapter 2, I describe the development of a technique to calibrate lidar digital elevation models with survey elevation data using readily available multispectral aerial imagery from the National Agricultural Inventory Program (NAIP). Using survey elevation data across 17 Pacific Coast tidal marshes, I demonstrated the utility of the Lidar Elevation Adjustment with NDVI (LEAN) technique to account for the positive bias in lidar due to vegetation. LEAN reduced error from an average of 23.1 cm to 7.2 cm root mean squared error and removed the positive bias caused by vegetation. This increase in accuracy will facilitate more accurate assessments of current and future vulnerability to sea-level rise. The phenology of aboveground biomass in tidal marsh plants in relation to climate variation has not been explored in the Pacific Northwest (PNW). In Chapter 3 I explain how I leveraged the Landsat archive and cloud computing capabilities to assess how Tasseled Cap Greenness (TCG, a proxy for aboveground biomass) in three PNW tidal marshes has responded to recent variation in climate to characterize sensitivity to climate change. Through analysis of over 3700 Landsat images obtained from 1984-2015, I found increased annual precipitation resulted in a higher peak TCG, while warmer May temperatures resulted in an earlier day of peak TCG. These results also demonstrate how time-series analysis of remote sensing data can be used to examine the sensitivity of tidal marsh plants to climate variability and directional change. The range of variation in tidal marsh accretion rates has not been characterized across the PNW. For Chapter 4, I collected and analyzed twenty-two soil cores from eight estuaries to estimate historic accretion rates with radioisotope dating techniques and evaluated the amount and source of variation across estuaries. I found that tidal marshes across the PNW had accretion rates greater than the current rate of sea-level rise, ranging from 2.3 – 7.3 mm yr⁻¹. Using a watershed-scale analysis, I found that long-term average annual fluvial discharge was the top predictor of tidal marsh accretion rates. Additionally, I found that calibrating the Wetland Accretion Rate Model for Ecosystem Resilience (WARMER) with accretion rate data from nearby estuaries can result in uncertainties of up to 41% (50 cm) after 100 years. Finally, in Chapter 5, I demonstrate that a range of 62 cm of error is possible in WARMER models after a 100 year simulation when both uncorrected lidar and non-local accretion rates are used, fundamentally changing the interpretation of the results. Altogether, this dissertation illustrates the importance of collecting site-specific wetland vegetation and elevation data and demonstrates how lidar and multispectral remote sensing data can be leveraged to improve our understanding of how climate variability and change impacts coastal ecosystems. Title: Improving Projections of Tidal Marsh Persistence under Climate Change with Remote Sensing and Site-Specific Data Author: Buffington, Kevin John Tidal marshes are dynamic ecosystems that are threatened by climate change and sea-level rise. To characterize baseline condition and historic climate sensitivities, and improve projections into the future, new methods are required that integrate data from the field and remote sensing platforms. Marsh elevation response models can be calibrated with site-specific data to determine the vulnerability of a marsh to sea-level rise and help guide management decisions. Elevation models are sensitive to initial elevation, the rate of accretion, and aboveground biomass. The overarching goal of this dissertation was to develop techniques to improve these important model inputs and evaluate the range of spatial and temporal variation. Light detection and ranging (lidar) is an invaluable tool for collecting elevation data, however dense vegetation prevents the accurate measurement of the tidal marsh surface. In Chapter 2, I describe the development of a technique to calibrate lidar digital elevation models with survey elevation data using readily available multispectral aerial imagery from the National Agricultural Inventory Program (NAIP). Using survey elevation data across 17 Pacific Coast tidal marshes, I demonstrated the utility of the Lidar Elevation Adjustment with NDVI (LEAN) technique to account for the positive bias in lidar due to vegetation. LEAN reduced error from an average of 23.1 cm to 7.2 cm root mean squared error and removed the positive bias caused by vegetation. This increase in accuracy will facilitate more accurate assessments of current and future vulnerability to sea-level rise. The phenology of aboveground biomass in tidal marsh plants in relation to climate variation has not been explored in the Pacific Northwest (PNW). In Chapter 3 I explain how I leveraged the Landsat archive and cloud computing capabilities to assess how Tasseled Cap Greenness (TCG, a proxy for aboveground biomass) in three PNW tidal marshes has responded to recent variation in climate to characterize sensitivity to climate change. Through analysis of over 3700 Landsat images obtained from 1984-2015, I found increased annual precipitation resulted in a higher peak TCG, while warmer May temperatures resulted in an earlier day of peak TCG. These results also demonstrate how time-series analysis of remote sensing data can be used to examine the sensitivity of tidal marsh plants to climate variability and directional change. The range of variation in tidal marsh accretion rates has not been characterized across the PNW. For Chapter 4, I collected and analyzed twenty-two soil cores from eight estuaries to estimate historic accretion rates with radioisotope dating techniques and evaluated the amount and source of variation across estuaries. I found that tidal marshes across the PNW had accretion rates greater than the current rate of sea-level rise, ranging from 2.3 – 7.3 mm yr⁻¹. Using a watershed-scale analysis, I found that long-term average annual fluvial discharge was the top predictor of tidal marsh accretion rates. Additionally, I found that calibrating the Wetland Accretion Rate Model for Ecosystem Resilience (WARMER) with accretion rate data from nearby estuaries can result in uncertainties of up to 41% (50 cm) after 100 years. Finally, in Chapter 5, I demonstrate that a range of 62 cm of error is possible in WARMER models after a 100 year simulation when both uncorrected lidar and non-local accretion rates are used, fundamentally changing the interpretation of the results. Altogether, this dissertation illustrates the importance of collecting site-specific wetland vegetation and elevation data and demonstrates how lidar and multispectral remote sensing data can be leveraged to improve our understanding of how climate variability and change impacts coastal ecosystems. Close

• 158. [Article] An evaluation of the likelihood of successful implementation of the long term coral reef monitoring program on the Commonwealth of the Northern Mariana Islands

  Coral reef ecosystems are the oceanic equivalent of tropical rainforests, in terms of biodiversity. The estimated 1,037,000 square kilometers worldwide of reef provide habitat for over one million species ...

  Citation × Citation Citation Abstract Copy Title: An evaluation of the likelihood of successful implementation of the long term coral reef monitoring program on the Commonwealth of the Northern Mariana Islands Author: Kylstra, Pam Coral reef ecosystems are the oceanic equivalent of tropical rainforests, in terms of biodiversity. The estimated 1,037,000 square kilometers worldwide of reef provide habitat for over one million species of plants and animals (Hinrichsen, 1997). Coral reefs are important to the economy of coastal nations because of the fisheries and tourism industries they support. Reef ecosystems provide a host of important natural services such as storm buffering, a protein source for islanders, breeding and nursery grounds for marine organisms, water filtration and a source of biomedically important products. Coral reef areas also have aesthetic and intrinsic value that is reason enough to protect them. Coral reefs are also among the most endangered ecosystems on Earth. Naturally occurring disturbances are compounded by the impacts of anthropogenic disturbance. Factors that threaten the health of coral reef ecosystems on a global scale include global warming, the continuing increase in coastal populations and associated impacts such as nutrient pollution, sedimentation and runoff, coral mining, ship groundings, overfishing, and recreational overuse. Globally, coastal areas accommodate about 60% of Earth's human population. A significant portion of the population lies within tropical regions. This population pressure subjects coral reef environments to effects of increased competition for coastal resources, increased coastal pollution and problems related to coastal construction. The synergistic effect of stressors has been the irreversible degradation worldwide of 10% of reefs and another 60% in critical condition leaving, only 30% as stable (Wilkinson, 1993). The coral reefs of the Commonwealth of the Northern Mariana Islands (CNMI) are a good example of how the combination of increasing human population and the associated environmental pressure has resulted in degradation of the reef ecosystem. The CNMI has undergone significant change in economic and population growth within the past decade. To accommodate the rapid and continuing development of the tourism industry, numerous golf courses and resort hotels have been constructed on Saipan. The population of Saipan has increased over 30% in the last ten years. Currently, the local/resident population is 60,000 while the visitor population is 750,000 per year. This rapid growth has had serious ecological consequences. Coral roads have been converted to four lane highways and infrastructure such as septic tank systems has not been improved to meet higher demand. More and more development projects have been proposed without adequate consideration of environmental impacts. Conflicts over the use and conservation of marine and watershed resources continue to arise. The continuing decline of reef systems globally and in specific areas like the CNMI, highlights the need for effective methods of assessing change in nearshore ecosystems. This paper explores the ways that coral reef monitoring can provide information about reef health that serves to affect positive changes in management strategies for marine systems. Using a criteria drawn from case study comparisons of ongoing, well established coral monitoring programs and evaluation framework proposed by policy analysts Using criteria drawn from case, the Long Term Marine Monitoring Program (LTMMP) on Saipan, CNMI is evaluated. The evaluation provides insight about coral monitoring plan components that are essential to the effectiveness of coral reef monitoring programs. This report is an outgrowth of an internship the author performed with the CNMI Division of Environmental Quality on the island of Saipan from June to October of 1997. The University of Oregon Micronesia and South Pacific Program and the government of the Commonwealth of the Northern Mariana Islands (CMNI) sponsored the internship project. The objectives of the internship were to assist in field data collection and continuing development of the ongoing Long Term Marine Monitoring Plan (LTMMP) Assist and instruct Marine Monitoring Team (MMT) members in basic computer skills, understanding of data applicability, management, interpretation and analysis, basic biology and resource management techniques as it relates to marine monitoring work Facilitate inter-governmental agency coordination of marine monitoring activities Assess likelihood of success and explore challenges facing Saipan in implementation of the monitoring program This report first describes functions and services provided by coral reefs and an introduction to the stresses and disturbances that compromise the health of reef systems globally. Using examples from case studies of established marine monitoring programs, this report considers how effective monitoring can reveal changes in the reef system over time, enabling conservation measures to be taken. It then turns to the island of Saipan and briefly describes the environmental and socio-economic framework within which the coral reef related provisions of the CNMI coastal management program are considered. This background information is used to evaluate the Long Term Marine Monitoring Plan currently in place on the CNMI. This evaluation provides insight into the challenges to implementation of coral reef monitoring plans and recommendations for improvements in the LTMMP on Saipan. Title: An evaluation of the likelihood of successful implementation of the long term coral reef monitoring program on the Commonwealth of the Northern Mariana Islands Author: Kylstra, Pam Coral reef ecosystems are the oceanic equivalent of tropical rainforests, in terms of biodiversity. The estimated 1,037,000 square kilometers worldwide of reef provide habitat for over one million species of plants and animals (Hinrichsen, 1997). Coral reefs are important to the economy of coastal nations because of the fisheries and tourism industries they support. Reef ecosystems provide a host of important natural services such as storm buffering, a protein source for islanders, breeding and nursery grounds for marine organisms, water filtration and a source of biomedically important products. Coral reef areas also have aesthetic and intrinsic value that is reason enough to protect them. Coral reefs are also among the most endangered ecosystems on Earth. Naturally occurring disturbances are compounded by the impacts of anthropogenic disturbance. Factors that threaten the health of coral reef ecosystems on a global scale include global warming, the continuing increase in coastal populations and associated impacts such as nutrient pollution, sedimentation and runoff, coral mining, ship groundings, overfishing, and recreational overuse. Globally, coastal areas accommodate about 60% of Earth's human population. A significant portion of the population lies within tropical regions. This population pressure subjects coral reef environments to effects of increased competition for coastal resources, increased coastal pollution and problems related to coastal construction. The synergistic effect of stressors has been the irreversible degradation worldwide of 10% of reefs and another 60% in critical condition leaving, only 30% as stable (Wilkinson, 1993). The coral reefs of the Commonwealth of the Northern Mariana Islands (CNMI) are a good example of how the combination of increasing human population and the associated environmental pressure has resulted in degradation of the reef ecosystem. The CNMI has undergone significant change in economic and population growth within the past decade. To accommodate the rapid and continuing development of the tourism industry, numerous golf courses and resort hotels have been constructed on Saipan. The population of Saipan has increased over 30% in the last ten years. Currently, the local/resident population is 60,000 while the visitor population is 750,000 per year. This rapid growth has had serious ecological consequences. Coral roads have been converted to four lane highways and infrastructure such as septic tank systems has not been improved to meet higher demand. More and more development projects have been proposed without adequate consideration of environmental impacts. Conflicts over the use and conservation of marine and watershed resources continue to arise. The continuing decline of reef systems globally and in specific areas like the CNMI, highlights the need for effective methods of assessing change in nearshore ecosystems. This paper explores the ways that coral reef monitoring can provide information about reef health that serves to affect positive changes in management strategies for marine systems. Using a criteria drawn from case study comparisons of ongoing, well established coral monitoring programs and evaluation framework proposed by policy analysts Using criteria drawn from case, the Long Term Marine Monitoring Program (LTMMP) on Saipan, CNMI is evaluated. The evaluation provides insight about coral monitoring plan components that are essential to the effectiveness of coral reef monitoring programs. This report is an outgrowth of an internship the author performed with the CNMI Division of Environmental Quality on the island of Saipan from June to October of 1997. The University of Oregon Micronesia and South Pacific Program and the government of the Commonwealth of the Northern Mariana Islands (CMNI) sponsored the internship project. The objectives of the internship were to assist in field data collection and continuing development of the ongoing Long Term Marine Monitoring Plan (LTMMP) Assist and instruct Marine Monitoring Team (MMT) members in basic computer skills, understanding of data applicability, management, interpretation and analysis, basic biology and resource management techniques as it relates to marine monitoring work Facilitate inter-governmental agency coordination of marine monitoring activities Assess likelihood of success and explore challenges facing Saipan in implementation of the monitoring program This report first describes functions and services provided by coral reefs and an introduction to the stresses and disturbances that compromise the health of reef systems globally. Using examples from case studies of established marine monitoring programs, this report considers how effective monitoring can reveal changes in the reef system over time, enabling conservation measures to be taken. It then turns to the island of Saipan and briefly describes the environmental and socio-economic framework within which the coral reef related provisions of the CNMI coastal management program are considered. This background information is used to evaluate the Long Term Marine Monitoring Plan currently in place on the CNMI. This evaluation provides insight into the challenges to implementation of coral reef monitoring plans and recommendations for improvements in the LTMMP on Saipan. Close

• 159. [Article] Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA

  Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future ...

  Citation × Citation Citation Abstract Copy Title: Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA Author: Kennedy, Rebecca S.H. Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future amounts of dead wood in two landscapes and region-wide in the Coastal Province of Oregon. The objectives of the first study were to (1) determine whether two landscapes with different recent disturbance histories differ in the amount and characteristics of dead wood; and (2) explore relationships between patterns of dead wood in each landscape to potentially related factors including topography. The objectives of the second study were to (1) describe current regional amounts of dead wood; (2) compare dead wood amounts across ownerships; (3) determine relationships between current dead wood amounts and ownership, current and past vegetation conditions, climate, topography, and soils; and (4) evaluate whether the factors related to dead wood patterns differed according to the scale of analysis. The objectives of the third study were to (1) characterize the projected future change in dead wood amounts in a multi-ownership Province; (2) determine the longevity of present-day dead wood of different types and sizes in relation to amendments from management and stand development; and (3) evaluate differences in management approaches in transitional dynamics and long-term patterns of dead wood. In the first study, I sampled logs and snags at four topographic positions (streams, lower slopes, middle slopes, upper slopes) in the Tillamook State Forest and the Siuslaw National Forest. These two landscapes experienced catastrophic fire at different points in recent history. I developed statistical models relating various attributes of dead wood abundance to biophysical variables related to climate, topography, historical vegetation, current vegetation, soils, and ecoregion. I found that the type and timing of disturbance was important to dead wood amounts and characteristics, and that potential source and sink areas for dead wood were related to topographic position. In particular, lower slopes had higher amounts of logs, and upper slopes had higher basal areas of potential source wood, in the form of snags and legacy (pre-fire) stumps. Climatic factors were of greater relative importance to overall gradients of dead wood in the landscape in which fire occurred less recently. In the second study, I analyzed dead wood data from a region-wide systematic grid of field plots according to ownership and biophysical variables at multiple scales of resolution including plots, subwatersheds. Dead wood abundance and types varied greatly among ownerships, with public lands (Forest Service, Bureau of Land Management, State of Oregon) typically having higher amounts of dead wood and more dead wood in the larger size classes than the private lands (forest industry, non-industrial private). I found that the relative influence of ownership, topography, current and historical vegetation, and climate varied with scale of resolution. Current vegetation was of greater relative importance at finer scales of plots and subwatersheds, whereas climate, topography, and historical vegetation were of greater relative importance at coarser scales of watersheds and subbasins. Ownership was important to overall dead wood gradients at all scales considered. In the third study, by simulating stand development and dead wood dynamics under various forest management scenarios over a 300-year period, I was able to examine the long-term effects of management on dead wood abundance in the Coastal Province. I estimated potential upper bounds for future dead wood amounts. Dead wood amounts increased over time on average across the Province, mainly because of policies on public lands, especially the federal lands under the Northwest Forest Plan. Forest industry, under the Oregon Forest Practices Act and assuming retention of all snags at harvest and thinning, maintained amounts of dead wood that were similar to present-day levels, but size classes shifted toward the smaller sizes as existing large legacy dead wood decomposed. Non-industrial private lands showed increases from very low present-day amounts of dead wood. Across the Province, legacy logs and snags remained present for over a century of the simulation period, and buffered effects of intensive management to dead wood amounts. Variation across landscapes in starting conditions meant that contrasting management approaches had differential effects on long-term dead wood dynamics depending on where they were applied. Current amounts of dead wood and live vegetation patterns in the Province resulted from historical fire and logging. Results of this simulation study indicate that recently established policies oriented toward dead wood production and retention, in the absence of fire or other large- or mid-scale disturbances, are likely to result in increases in dead wood amounts that greatly exceed present-day levels. My results suggest that dead wood patterns of abundance will continue to diverge according to land ownership and that management practices that foster dead wood creation are of increasing importance to the long-term abundance of large dead wood as legacy dead wood is lost through decomposition. Title: Dead wood dynamics and relationships to biophysical factors, forest history, ownership, and management practices in the Coastal Province of Oregon, USA Author: Kennedy, Rebecca S.H. Dead wood patterns and dynamics vary with biophysical factors, disturbance history, ownership, and management practices. Through field and modeling studies, I examined the current and potential future amounts of dead wood in two landscapes and region-wide in the Coastal Province of Oregon. The objectives of the first study were to (1) determine whether two landscapes with different recent disturbance histories differ in the amount and characteristics of dead wood; and (2) explore relationships between patterns of dead wood in each landscape to potentially related factors including topography. The objectives of the second study were to (1) describe current regional amounts of dead wood; (2) compare dead wood amounts across ownerships; (3) determine relationships between current dead wood amounts and ownership, current and past vegetation conditions, climate, topography, and soils; and (4) evaluate whether the factors related to dead wood patterns differed according to the scale of analysis. The objectives of the third study were to (1) characterize the projected future change in dead wood amounts in a multi-ownership Province; (2) determine the longevity of present-day dead wood of different types and sizes in relation to amendments from management and stand development; and (3) evaluate differences in management approaches in transitional dynamics and long-term patterns of dead wood. In the first study, I sampled logs and snags at four topographic positions (streams, lower slopes, middle slopes, upper slopes) in the Tillamook State Forest and the Siuslaw National Forest. These two landscapes experienced catastrophic fire at different points in recent history. I developed statistical models relating various attributes of dead wood abundance to biophysical variables related to climate, topography, historical vegetation, current vegetation, soils, and ecoregion. I found that the type and timing of disturbance was important to dead wood amounts and characteristics, and that potential source and sink areas for dead wood were related to topographic position. In particular, lower slopes had higher amounts of logs, and upper slopes had higher basal areas of potential source wood, in the form of snags and legacy (pre-fire) stumps. Climatic factors were of greater relative importance to overall gradients of dead wood in the landscape in which fire occurred less recently. In the second study, I analyzed dead wood data from a region-wide systematic grid of field plots according to ownership and biophysical variables at multiple scales of resolution including plots, subwatersheds. Dead wood abundance and types varied greatly among ownerships, with public lands (Forest Service, Bureau of Land Management, State of Oregon) typically having higher amounts of dead wood and more dead wood in the larger size classes than the private lands (forest industry, non-industrial private). I found that the relative influence of ownership, topography, current and historical vegetation, and climate varied with scale of resolution. Current vegetation was of greater relative importance at finer scales of plots and subwatersheds, whereas climate, topography, and historical vegetation were of greater relative importance at coarser scales of watersheds and subbasins. Ownership was important to overall dead wood gradients at all scales considered. In the third study, by simulating stand development and dead wood dynamics under various forest management scenarios over a 300-year period, I was able to examine the long-term effects of management on dead wood abundance in the Coastal Province. I estimated potential upper bounds for future dead wood amounts. Dead wood amounts increased over time on average across the Province, mainly because of policies on public lands, especially the federal lands under the Northwest Forest Plan. Forest industry, under the Oregon Forest Practices Act and assuming retention of all snags at harvest and thinning, maintained amounts of dead wood that were similar to present-day levels, but size classes shifted toward the smaller sizes as existing large legacy dead wood decomposed. Non-industrial private lands showed increases from very low present-day amounts of dead wood. Across the Province, legacy logs and snags remained present for over a century of the simulation period, and buffered effects of intensive management to dead wood amounts. Variation across landscapes in starting conditions meant that contrasting management approaches had differential effects on long-term dead wood dynamics depending on where they were applied. Current amounts of dead wood and live vegetation patterns in the Province resulted from historical fire and logging. Results of this simulation study indicate that recently established policies oriented toward dead wood production and retention, in the absence of fire or other large- or mid-scale disturbances, are likely to result in increases in dead wood amounts that greatly exceed present-day levels. My results suggest that dead wood patterns of abundance will continue to diverge according to land ownership and that management practices that foster dead wood creation are of increasing importance to the long-term abundance of large dead wood as legacy dead wood is lost through decomposition. Close

• 160. [Article] Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin

  Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has ...

  Citation × Citation Citation Abstract Copy Title: Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin Author: Eiler, John H. Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has raised concerns over the future status of the returns, and severely impacted commercial and subsistence fisheries within the drainage. Management is further complicated by the mixed-stock composition of the run, the presence of other temporally similar salmon species, and the need to equitably allocate harvests between the numerous fisheries and user groups scattered throughout the basin. Detailed information is needed on Chinook salmon run characteristics to better understand and manage the returns, and facilitate conservation efforts. However, this goal is exacerbated by the massive size and remote nature of the basin, the large number of highly mobile fish, and the compressed timing of the run. To address these challenges, radio telemetry was used to determine the stock composition and spawning distribution of the returns, and the migratory characteristics of the fish. The migratory patterns exhibited by returning salmon provide a number of insights into the status of the run. Since the Yukon River is essentially free-flowing (i.e., not regulated), this study also presented an opportunity to document the distribution and upriver movements of large returns of wild Chinook salmon under natural conditions. During 2002-2004, returning adult Chinook salmon were captured in the lower Yukon River (approximately 300 km upriver from the river mouth), tagged with radio transmitters, and tracked upriver using remote tracking stations located on important migratory routes and major spawning tributaries. Aerial tracking surveys were used to locate fish in spawning areas and between stations. The fish responded well to the capture and handling procedures, with most (2,790, 98%) resuming upriver movements. Although the fish initially displayed a negative tagging response, with slower migration rates observed immediately after release, the duration of this response was relatively short (several days) and less severe as the fish moved upriver. Independent measures indicated that the swimming speeds and timing of the fish upriver from the tagging area were comparable to untagged fish, suggesting that the tagging methods used were relatively benign. Fish returned to spawning areas throughout the basin, ranging from several hundred to over 3,000 km from the tagging area. Distribution patterns were similar across years, suggesting that the principal components of the run were identified. Most spawning fish were clustered in a number of key tributaries, with smaller numbers of fish located in other spatially isolated areas. The fish typically returned to clear water tributaries that were relatively entrenched, had moderate gradients, and were associated with upland areas. Fish were largely absent in lowland reaches characterized by meandering, low gradient, highly alluvial channels often associated with main river floodplains. There was suggestive evidence of mainstem spawning in reaches of the Upper Yukon. The status of fish remaining in other mainstem areas was less certain, and may represent local spawning activity or fish that died while in-transit to upriver areas. Although Chinook salmon spawned throughout the basin, the run was dominated by two regional components (Tanana and Upper Yukon), which annually comprised over 70% of the return. Substantially fewer fish returned to other areas ranging from 2-9% of the return, although the collective contribution of these stocks was appreciable. Most regional returns consisted of several principal stocks and a number of small, spatially isolated populations. Regional and stock composition estimates were similar across years even though differences in run abundance were reported, suggesting that these abundance differences were not related to regional or stock-specific differences. Run timing was relatively compressed compared to rivers in the southern portion of the range, with most stocks passing through the lower river over a 6-week period, ranging from 16 to 38 d. Run timing was generally earlier for stocks traveling farther upriver, although exceptions were noted. Lower basin stocks were primarily later run fish. Pronounced differences were observed in the migration rates (km/d) exhibited by regional stocks. Substantially slower swimming speeds were observed for fish returning to terminal tributaries in the lower basin ranging from 28-40 km/d compared to 52-62 km/d for upper basin stocks. The migratory patterns (migration rates in sequential reaches) of the fish also showed distinct regional differences. Average migration rates through the lower river were remarkably similar for the different stocks, ranging from 57-62 km/d, with most stocks exhibiting a general decline as the fish moved farther upriver. Tanana River stocks displayed a pronounced reduction in swimming speed after leaving the Yukon River main stem, with migration rates declining to 24 km/d on average as the fish approached their terminal tributaries. Conversely, upper basin stocks exhibited a relatively gradual (but variable) overall decline in migration rate even though these fish were traveling substantially greater distances upriver. Average migration rates for upper basin stocks ranged from 43-61 km/d as the fish approached their terminal tributaries. There was substantial variation in the migratory patterns exhibited by individual fish, although these patterns tended to be similar to the patterns exhibited by the regional stocks, particularly as the fish moved farther upriver from the tagging area. The dominant source of variation among fish reflected the average migration rate, with individual fish traveling slower in the lower basin exhibiting consistently slower migration rates as they moved upriver compared to their faster moving counterparts. This migratory pattern was consistent across stocks, and on average explained 74% of the within-stock variation in migration rate represented by the multivariate data. The second source of variation in migration rate reflected a shift in the relative swimming speeds of the individual fish as they progressed upriver. Although movement rates declined for nearly all of the fish during the migration, differences were observed in the pattern of the decline. Fish with faster migration rates in the lower river exhibited a pronounced decline in swimming speed as they moved upriver, whereas fish moving slower in the lower river displayed a more gradual decline in migration rate. On average, this migratory pattern explained 22% of the within-stock variation in migration rate represented by the multivariate data. Most fish (98%) exhibited continuous upriver movements and strong fidelity to the rivers they entered. However a small number of fish (n = 66) deviated from this pattern. Some of these individuals initially passed their final destination and continued upriver for varying distances before reversing direction, swimming back downstream, and entering their terminal tributary. Although most of these excursions were relatively short (< 30 km), there were several instances where fish traveled hundreds of kilometers out of their way. Thirty-four fish tracked to terminal tributaries subsequently left these rivers, and traveled to other terminal tributaries within the basin (n = 31) or were harvested in upriver fisheries (n = 3). Although most of these incidents involved nearby tributaries, major diversions were also observed, with several fish traveling over 300 km to natal rivers after leaving the initial tributary. Chinook salmon returns to the Yukon River typically consisted of a series of distinct and sizable increases in the number fish entering the river over the course of the run, commonly referred to as pulses. A large number of fish (n = 251) were radio tagged over a 4-day period during a pulse in 2003 to provide information on the progression of the pulse as it moved upriver. The time taken by the pulse to move past subsequent upriver locations increased as the fish moved farther upriver from the tagging area, with the fish passing sites located 580 and 800 km upriver over a span of 14 and 21 d, respectively. Although not surprising considering the extensive variation in migration rates observed among individual fish, this finding does suggest that these pulses do not represent cohesive aggregates of fish moving upriver. Unlike the well established methods used to estimate other life history characteristics, the development of quantitative methods for analyzing and modeling fish movements has lagged noticeably behind, due in part to the complexity associated with movement data and (prior to the advent of telemetry) the difficulty of collecting this type of information on free-ranging individuals. Two fundamentally different analytical approaches, hierarchical linear regression models and multivariate ordination, were used during this study to evaluate factors thought to influence the upriver movements of the fish. In spite of the inherent differences, both methods provided strikingly similar results, indicating that the study findings were not dependent on the approach used, and suggesting that the results were plausible based on the information available and the weight of evidence. Both analytical methods had advantages, and provided complementary information. With hierarchical linear models, it was possible to simultaneously evaluate a wide range of explanatory variables (in our case, both biological and environmental), which provided standardized comparisons and simplified the interpretation of the results. Since both fixed and random effects were incorporated in the models, it was possible to account for sources of variation when insufficient information was available to identify the underlining factors – an important consideration since few field studies provide comprehensive data. With multivariate ordination, separate analyzes were needed to examine the relationships between the migration rates and the biotic and physical variables. In addition to being cumbersome, this limitation made it more difficult to compare the relative influence of the different factors and interactions between factors. However, ordination was very useful as an exploratory tool. Although compartmentalized by stock, across fish comparisons were simple and relatively straightforward. Because the explanatory variables were evaluated separately in relation to the ordination score assigned to the fish, it was possible to examine and compare highly correlated variables. Ordination was also able to identify overall patterns within the data and assess the relative importance. While this can be accomplished within the framework of linear regression using mixture models to determine whether multiple distributions exist within the data, the process is much simpler with ordination. The migratory patterns of the fish were influenced by a wide range of factors, with evidentiary support for complex, multi-faceted relationships. Physical features of the basin demonstrated stronger explanatory power, accounting for over 70% of the observed variation in migration rate compared to 18% for the biological characteristics of the fish. Parameter estimates associated with the steepness of the migratory route and remaining distance the fish had to travel to reach their natal rivers were most strongly correlated with migration rate, with consistent relationships observed across stocks. Migration rates were also noticeably slower in extensively braided reaches of the basin. The weaker relationships between migration rate and biotic factors may reflect stabilizing selection on long-distance migrants. Smaller fish exhibited minimally faster swimming speeds on average than larger individuals. This relationship was stronger in highly braided reaches. Run timing was positively related to migration rate for most stocks. Surprisingly, upper basin stocks traveling farther upriver displayed progressively negative relationships, suggesting that late-run fish were moving slower. Ancillary information suggests that this decline may relate to deteriorating fish condition later in the season. Title: Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin Author: Eiler, John H. Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has raised concerns over the future status of the returns, and severely impacted commercial and subsistence fisheries within the drainage. Management is further complicated by the mixed-stock composition of the run, the presence of other temporally similar salmon species, and the need to equitably allocate harvests between the numerous fisheries and user groups scattered throughout the basin. Detailed information is needed on Chinook salmon run characteristics to better understand and manage the returns, and facilitate conservation efforts. However, this goal is exacerbated by the massive size and remote nature of the basin, the large number of highly mobile fish, and the compressed timing of the run. To address these challenges, radio telemetry was used to determine the stock composition and spawning distribution of the returns, and the migratory characteristics of the fish. The migratory patterns exhibited by returning salmon provide a number of insights into the status of the run. Since the Yukon River is essentially free-flowing (i.e., not regulated), this study also presented an opportunity to document the distribution and upriver movements of large returns of wild Chinook salmon under natural conditions. During 2002-2004, returning adult Chinook salmon were captured in the lower Yukon River (approximately 300 km upriver from the river mouth), tagged with radio transmitters, and tracked upriver using remote tracking stations located on important migratory routes and major spawning tributaries. Aerial tracking surveys were used to locate fish in spawning areas and between stations. The fish responded well to the capture and handling procedures, with most (2,790, 98%) resuming upriver movements. Although the fish initially displayed a negative tagging response, with slower migration rates observed immediately after release, the duration of this response was relatively short (several days) and less severe as the fish moved upriver. Independent measures indicated that the swimming speeds and timing of the fish upriver from the tagging area were comparable to untagged fish, suggesting that the tagging methods used were relatively benign. Fish returned to spawning areas throughout the basin, ranging from several hundred to over 3,000 km from the tagging area. Distribution patterns were similar across years, suggesting that the principal components of the run were identified. Most spawning fish were clustered in a number of key tributaries, with smaller numbers of fish located in other spatially isolated areas. The fish typically returned to clear water tributaries that were relatively entrenched, had moderate gradients, and were associated with upland areas. Fish were largely absent in lowland reaches characterized by meandering, low gradient, highly alluvial channels often associated with main river floodplains. There was suggestive evidence of mainstem spawning in reaches of the Upper Yukon. The status of fish remaining in other mainstem areas was less certain, and may represent local spawning activity or fish that died while in-transit to upriver areas. Although Chinook salmon spawned throughout the basin, the run was dominated by two regional components (Tanana and Upper Yukon), which annually comprised over 70% of the return. Substantially fewer fish returned to other areas ranging from 2-9% of the return, although the collective contribution of these stocks was appreciable. Most regional returns consisted of several principal stocks and a number of small, spatially isolated populations. Regional and stock composition estimates were similar across years even though differences in run abundance were reported, suggesting that these abundance differences were not related to regional or stock-specific differences. Run timing was relatively compressed compared to rivers in the southern portion of the range, with most stocks passing through the lower river over a 6-week period, ranging from 16 to 38 d. Run timing was generally earlier for stocks traveling farther upriver, although exceptions were noted. Lower basin stocks were primarily later run fish. Pronounced differences were observed in the migration rates (km/d) exhibited by regional stocks. Substantially slower swimming speeds were observed for fish returning to terminal tributaries in the lower basin ranging from 28-40 km/d compared to 52-62 km/d for upper basin stocks. The migratory patterns (migration rates in sequential reaches) of the fish also showed distinct regional differences. Average migration rates through the lower river were remarkably similar for the different stocks, ranging from 57-62 km/d, with most stocks exhibiting a general decline as the fish moved farther upriver. Tanana River stocks displayed a pronounced reduction in swimming speed after leaving the Yukon River main stem, with migration rates declining to 24 km/d on average as the fish approached their terminal tributaries. Conversely, upper basin stocks exhibited a relatively gradual (but variable) overall decline in migration rate even though these fish were traveling substantially greater distances upriver. Average migration rates for upper basin stocks ranged from 43-61 km/d as the fish approached their terminal tributaries. There was substantial variation in the migratory patterns exhibited by individual fish, although these patterns tended to be similar to the patterns exhibited by the regional stocks, particularly as the fish moved farther upriver from the tagging area. The dominant source of variation among fish reflected the average migration rate, with individual fish traveling slower in the lower basin exhibiting consistently slower migration rates as they moved upriver compared to their faster moving counterparts. This migratory pattern was consistent across stocks, and on average explained 74% of the within-stock variation in migration rate represented by the multivariate data. The second source of variation in migration rate reflected a shift in the relative swimming speeds of the individual fish as they progressed upriver. Although movement rates declined for nearly all of the fish during the migration, differences were observed in the pattern of the decline. Fish with faster migration rates in the lower river exhibited a pronounced decline in swimming speed as they moved upriver, whereas fish moving slower in the lower river displayed a more gradual decline in migration rate. On average, this migratory pattern explained 22% of the within-stock variation in migration rate represented by the multivariate data. Most fish (98%) exhibited continuous upriver movements and strong fidelity to the rivers they entered. However a small number of fish (n = 66) deviated from this pattern. Some of these individuals initially passed their final destination and continued upriver for varying distances before reversing direction, swimming back downstream, and entering their terminal tributary. Although most of these excursions were relatively short (< 30 km), there were several instances where fish traveled hundreds of kilometers out of their way. Thirty-four fish tracked to terminal tributaries subsequently left these rivers, and traveled to other terminal tributaries within the basin (n = 31) or were harvested in upriver fisheries (n = 3). Although most of these incidents involved nearby tributaries, major diversions were also observed, with several fish traveling over 300 km to natal rivers after leaving the initial tributary. Chinook salmon returns to the Yukon River typically consisted of a series of distinct and sizable increases in the number fish entering the river over the course of the run, commonly referred to as pulses. A large number of fish (n = 251) were radio tagged over a 4-day period during a pulse in 2003 to provide information on the progression of the pulse as it moved upriver. The time taken by the pulse to move past subsequent upriver locations increased as the fish moved farther upriver from the tagging area, with the fish passing sites located 580 and 800 km upriver over a span of 14 and 21 d, respectively. Although not surprising considering the extensive variation in migration rates observed among individual fish, this finding does suggest that these pulses do not represent cohesive aggregates of fish moving upriver. Unlike the well established methods used to estimate other life history characteristics, the development of quantitative methods for analyzing and modeling fish movements has lagged noticeably behind, due in part to the complexity associated with movement data and (prior to the advent of telemetry) the difficulty of collecting this type of information on free-ranging individuals. Two fundamentally different analytical approaches, hierarchical linear regression models and multivariate ordination, were used during this study to evaluate factors thought to influence the upriver movements of the fish. In spite of the inherent differences, both methods provided strikingly similar results, indicating that the study findings were not dependent on the approach used, and suggesting that the results were plausible based on the information available and the weight of evidence. Both analytical methods had advantages, and provided complementary information. With hierarchical linear models, it was possible to simultaneously evaluate a wide range of explanatory variables (in our case, both biological and environmental), which provided standardized comparisons and simplified the interpretation of the results. Since both fixed and random effects were incorporated in the models, it was possible to account for sources of variation when insufficient information was available to identify the underlining factors – an important consideration since few field studies provide comprehensive data. With multivariate ordination, separate analyzes were needed to examine the relationships between the migration rates and the biotic and physical variables. In addition to being cumbersome, this limitation made it more difficult to compare the relative influence of the different factors and interactions between factors. However, ordination was very useful as an exploratory tool. Although compartmentalized by stock, across fish comparisons were simple and relatively straightforward. Because the explanatory variables were evaluated separately in relation to the ordination score assigned to the fish, it was possible to examine and compare highly correlated variables. Ordination was also able to identify overall patterns within the data and assess the relative importance. While this can be accomplished within the framework of linear regression using mixture models to determine whether multiple distributions exist within the data, the process is much simpler with ordination. The migratory patterns of the fish were influenced by a wide range of factors, with evidentiary support for complex, multi-faceted relationships. Physical features of the basin demonstrated stronger explanatory power, accounting for over 70% of the observed variation in migration rate compared to 18% for the biological characteristics of the fish. Parameter estimates associated with the steepness of the migratory route and remaining distance the fish had to travel to reach their natal rivers were most strongly correlated with migration rate, with consistent relationships observed across stocks. Migration rates were also noticeably slower in extensively braided reaches of the basin. The weaker relationships between migration rate and biotic factors may reflect stabilizing selection on long-distance migrants. Smaller fish exhibited minimally faster swimming speeds on average than larger individuals. This relationship was stronger in highly braided reaches. Run timing was positively related to migration rate for most stocks. Surprisingly, upper basin stocks traveling farther upriver displayed progressively negative relationships, suggesting that late-run fish were moving slower. Ancillary information suggests that this decline may relate to deteriorating fish condition later in the season. Close