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• 11. [Article] Watershed Solutions: Collaborative Problem Solving for States and Communities

  In July 2002, the National Policy Consensus Center (NPCC) hosted a colloquium for people involved in watershed collaborations, academics, and other experts from government and non-profit organizations. ...

  Citation × Citation Citation Abstract Copy Title: Watershed Solutions: Collaborative Problem Solving for States and Communities Author: National Policy Consensus Center Year: 2002 In July 2002, the National Policy Consensus Center (NPCC) hosted a colloquium for people involved in watershed collaborations, academics, and other experts from government and non-profit organizations. Its aim was to identify lessons learned from successful watershed initiatives, and to develop recommendations for governors and other state officials on ways to enhance the use and effectiveness of watershed partnerships. This report is an outgrowth of that conference. Studies on watershed collaborations are beginning to identify what makes them successful and what some of the barriers are to greater success. For example, contrary to the fears of some observers, successful collaborations do not shy away from controversial issues. Drawing on a growing list of best practices and lessons learned from experiences across the country, state officials and local partners can be better assured of successful outcomes in collaborative watershed management initiatives. Title: Watershed Solutions: Collaborative Problem Solving for States and Communities Author: National Policy Consensus Center Year: 2002 In July 2002, the National Policy Consensus Center (NPCC) hosted a colloquium for people involved in watershed collaborations, academics, and other experts from government and non-profit organizations. Its aim was to identify lessons learned from successful watershed initiatives, and to develop recommendations for governors and other state officials on ways to enhance the use and effectiveness of watershed partnerships. This report is an outgrowth of that conference. Studies on watershed collaborations are beginning to identify what makes them successful and what some of the barriers are to greater success. For example, contrary to the fears of some observers, successful collaborations do not shy away from controversial issues. Drawing on a growing list of best practices and lessons learned from experiences across the country, state officials and local partners can be better assured of successful outcomes in collaborative watershed management initiatives. Close

• 12. [Article] Urban and Rural-residential Land Uses: Their Role in Watershed Health and the Rehabilitation of Oregon’s Wild Salmonids

  This technical report by the Independent Multidisciplinary Science Team (IMST) is a comprehensive review of how human activities in urban and rural-residential areas can alter aquatic ecosystems and resulting ...

  Citation × Citation Citation Abstract Copy Title: Urban and Rural-residential Land Uses: Their Role in Watershed Health and the Rehabilitation of Oregon’s Wild Salmonids Author: Harte, Michael, Kaczynski, Victor W., Shock, Clinton C., Yeakley, J. Alan, Hughes, Robert M., Molina, Nancy, Schreck, Carl B. Year: 2010 This technical report by the Independent Multidisciplinary Science Team (IMST) is a comprehensive review of how human activities in urban and rural-residential areas can alter aquatic ecosystems and resulting implications for salmonid recovery, with a geographic focus on the state of Oregon. The following topics are considered in the form of science questions, and comprise the major components of this report: The effects of urban and rural-residential development on Oregon’s watersheds and native wild salmonids. Actions that can be used to avoid or mitigate undesirable changes to aquatic ecosystems near developing urban and rural-residential areas. The benefits and pitfalls of salmonid habitat rehabilitation within established urban or rural-residential areas. Suggested research and monitoring focus areas that will facilitate the recovery of salmonid populations affected by development. The fundamental concepts presented in this report should be applicable to most native salmonid populations across the state. IMST encourages managers and policy-makers with interest in a specific species or geographic region to carefully research local ecological conditions, as well as specific life history characteristics of salmonids in the region. Conserving watershed condition and salmonids in the face of increasing development requires consideration of two distinct sets of processes. First are the human social and economic processes that drive patterns in land use change. Second are the ecological processes, altered by land use, that underlie salmonid habitat changes. This report focuses on the latter and summarizes the effects of rural-residential and urban development on native, wild salmonid populations and the watersheds upon which they depend. Title: Urban and Rural-residential Land Uses: Their Role in Watershed Health and the Rehabilitation of Oregon’s Wild Salmonids Author: Harte, Michael, Kaczynski, Victor W., Shock, Clinton C., Yeakley, J. Alan, Hughes, Robert M., Molina, Nancy, Schreck, Carl B. Year: 2010 This technical report by the Independent Multidisciplinary Science Team (IMST) is a comprehensive review of how human activities in urban and rural-residential areas can alter aquatic ecosystems and resulting implications for salmonid recovery, with a geographic focus on the state of Oregon. The following topics are considered in the form of science questions, and comprise the major components of this report: The effects of urban and rural-residential development on Oregon’s watersheds and native wild salmonids. Actions that can be used to avoid or mitigate undesirable changes to aquatic ecosystems near developing urban and rural-residential areas. The benefits and pitfalls of salmonid habitat rehabilitation within established urban or rural-residential areas. Suggested research and monitoring focus areas that will facilitate the recovery of salmonid populations affected by development. The fundamental concepts presented in this report should be applicable to most native salmonid populations across the state. IMST encourages managers and policy-makers with interest in a specific species or geographic region to carefully research local ecological conditions, as well as specific life history characteristics of salmonids in the region. Conserving watershed condition and salmonids in the face of increasing development requires consideration of two distinct sets of processes. First are the human social and economic processes that drive patterns in land use change. Second are the ecological processes, altered by land use, that underlie salmonid habitat changes. This report focuses on the latter and summarizes the effects of rural-residential and urban development on native, wild salmonid populations and the watersheds upon which they depend. Close

• 13. [Article] Informing Oregon's Marine Protected Area (MPA) Baseline: Past and Present Tribal Uses of Marine Resources

  Native American tribes with ancestral land adjacent to the coast have gathered, hunted, and fished marine resources for millennia. In 2012, the state of Oregon designated five marine sites as reserves ...

  Citation × Citation Citation Abstract Copy Title: Informing Oregon's Marine Protected Area (MPA) Baseline: Past and Present Tribal Uses of Marine Resources Author: Comet, Sabra Marie TallChief Year: 2017 Native American tribes with ancestral land adjacent to the coast have gathered, hunted, and fished marine resources for millennia. In 2012, the state of Oregon designated five marine sites as reserves in which ocean development and harvest were prohibited. Marine Protected Areas (MPAs) are paired with each of the reserves and have less stringent “take” restrictions. Conflict over tribal use of MPAs have arisen in other states (e.g., California) as designation of MPAs and Reserves can impact subsistence, ceremonial, and traditional uses. My master’s thesis is intended to inform Oregon MPA management by developing a dataset that will describe tribal past (ancestral) and present (recent, within the current generation) uses of marine resources. I have collected interview and survey data to document marine resource use by tribal peoples on the Oregon coast in or near current and planned MPA’s. The interview protocols I used were developed for northern California’s MPA Baseline project and use a mixture of long and short questions, as well as an interactive mapping exercise. Interviews will target current fishermen/gatherers and tribal elders. Outcomes from the project will help Oregon coastal managers incorporate tribal uses into MPA management. Title: Informing Oregon's Marine Protected Area (MPA) Baseline: Past and Present Tribal Uses of Marine Resources Author: Comet, Sabra Marie TallChief Year: 2017 Native American tribes with ancestral land adjacent to the coast have gathered, hunted, and fished marine resources for millennia. In 2012, the state of Oregon designated five marine sites as reserves in which ocean development and harvest were prohibited. Marine Protected Areas (MPAs) are paired with each of the reserves and have less stringent “take” restrictions. Conflict over tribal use of MPAs have arisen in other states (e.g., California) as designation of MPAs and Reserves can impact subsistence, ceremonial, and traditional uses. My master’s thesis is intended to inform Oregon MPA management by developing a dataset that will describe tribal past (ancestral) and present (recent, within the current generation) uses of marine resources. I have collected interview and survey data to document marine resource use by tribal peoples on the Oregon coast in or near current and planned MPA’s. The interview protocols I used were developed for northern California’s MPA Baseline project and use a mixture of long and short questions, as well as an interactive mapping exercise. Interviews will target current fishermen/gatherers and tribal elders. Outcomes from the project will help Oregon coastal managers incorporate tribal uses into MPA management. Close

• 14. [Article] Relationships Between Environmental Governance and Water Quality in a Growing Metropolitan Area of the Pacific Northwest, USA

  We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro ...

  Citation × Citation Citation Abstract Copy Title: Relationships Between Environmental Governance and Water Quality in a Growing Metropolitan Area of the Pacific Northwest, USA Author: Chang, Heejun, Thiers, Paul R., Netusil, Noelwah R., Yeakley, J. Alan, Rollwagen-Bollens, Gretchen, Bollens, Steve, Singh, Sonia Year: 2014 We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro areas share many common biophysical characteristics, they have different land development histories and water governance structures, providing a unique opportunity for examining how differences in governance might affect environmental quality. We conceptualize possible linkages in which water quality influences governance directly, using monitoring efforts as a metric, and indirectly by using the change in the sale price of single-family residential properties. Governance may then influence water quality directly through riparian restoration resulting from monitoring results and indirectly through land use policy.We investigate evidence to substantiate these linkages. Our results showed that changes in monitoring regimes and land development patterns differed in response to differences in growth management policy and environmental governance systems. Our results also showed similarities in environmental quality responses to varying governance systems. For example, we found that sales prices responded positively to improved water quality (e.g., increases in DO and reductions in bacteria counts) in both cities. Furthermore, riparian restoration efforts improved over time for both cities, indicating the positive effect of governance on this land-based resource that may result in improved water quality. However, as of yet, there were no substantial differences across study areas in water temperature over time, despite an expansion of these urban areas of more than 20%over 24 years. The mechanisms by which water quality was maintained was similar in the sense that both cities benefited from riparian restoration, but different in the sense that Portland benefited indirectly from land use policy. A combination of long-term legacy effects of land development, and a relatively short history of riparian restoration in both the Portland and Vancouver regions, may have masked any subtle differences between study areas. An alternative explanation is that both cities exhibited combinations of positive indirect and direct water quality governance that resulted in maintenance of water quality in the face of increased urban growth. These findings suggest that a much longer-term water quality monitoring effort is needed to identify the effectiveness of alternative land development and water governance policies Title: Relationships Between Environmental Governance and Water Quality in a Growing Metropolitan Area of the Pacific Northwest, USA Author: Chang, Heejun, Thiers, Paul R., Netusil, Noelwah R., Yeakley, J. Alan, Rollwagen-Bollens, Gretchen, Bollens, Steve, Singh, Sonia Year: 2014 We investigate relationships between environmental governance and water quality in two adjacent growing metropolitan areas in the western US. While the Portland, Oregon and Vancouver, Washington metro areas share many common biophysical characteristics, they have different land development histories and water governance structures, providing a unique opportunity for examining how differences in governance might affect environmental quality. We conceptualize possible linkages in which water quality influences governance directly, using monitoring efforts as a metric, and indirectly by using the change in the sale price of single-family residential properties. Governance may then influence water quality directly through riparian restoration resulting from monitoring results and indirectly through land use policy.We investigate evidence to substantiate these linkages. Our results showed that changes in monitoring regimes and land development patterns differed in response to differences in growth management policy and environmental governance systems. Our results also showed similarities in environmental quality responses to varying governance systems. For example, we found that sales prices responded positively to improved water quality (e.g., increases in DO and reductions in bacteria counts) in both cities. Furthermore, riparian restoration efforts improved over time for both cities, indicating the positive effect of governance on this land-based resource that may result in improved water quality. However, as of yet, there were no substantial differences across study areas in water temperature over time, despite an expansion of these urban areas of more than 20%over 24 years. The mechanisms by which water quality was maintained was similar in the sense that both cities benefited from riparian restoration, but different in the sense that Portland benefited indirectly from land use policy. A combination of long-term legacy effects of land development, and a relatively short history of riparian restoration in both the Portland and Vancouver regions, may have masked any subtle differences between study areas. An alternative explanation is that both cities exhibited combinations of positive indirect and direct water quality governance that resulted in maintenance of water quality in the face of increased urban growth. These findings suggest that a much longer-term water quality monitoring effort is needed to identify the effectiveness of alternative land development and water governance policies Close

• 15. [Article] Effects of Beaver Dams on Surface Water Flow During Storm Events in an Urban Landscape

  Urban land-use generally alters the hydrologic cycle, leading to changes in the natural flow regime of local streams. Runoff from impervious surfaces and routing of stormwater to streams causes urban streams ...

  Citation × Citation Citation Abstract Copy Title: Effects of Beaver Dams on Surface Water Flow During Storm Events in an Urban Landscape Author: Poor, Erin Year: 2017 Urban land-use generally alters the hydrologic cycle, leading to changes in the natural flow regime of local streams. Runoff from impervious surfaces and routing of stormwater to streams causes urban streams to respond quickly and more intensely to storm events-more so than then would be observed in a less urbanized landscape. The rapid pulse of water that is routed to streams during precipitation events can degrade the physical structure of the channel and alter water quality and habitat availability. To manage these common urban stream issues, agencies have been seeking alternative ways of restoring and enhancing resilience in urban stream networks within the constraints of existing infrastructure. One potential strategy may be to support beaver recolonization of urban streams. This is because beaver dam building activity has been found to attenuate streamflow in areas that have experienced minimal human impact. Currently, however, no studies have been published that examine how beaver dams affect stream flow in altered urban systems. This study seeks to determine if the presence of beaver dams and ponds in urban stream reaches in the Tualatin River basin, Oregon, modifies the stream’s response to storm events. Continuous surface water levels are being collected upstream and downstream of two beaver affected reaches in order to determine how the presence of dams and ponds affect the flow regime, and whether this more closely resembles a less degraded state. Title: Effects of Beaver Dams on Surface Water Flow During Storm Events in an Urban Landscape Author: Poor, Erin Year: 2017 Urban land-use generally alters the hydrologic cycle, leading to changes in the natural flow regime of local streams. Runoff from impervious surfaces and routing of stormwater to streams causes urban streams to respond quickly and more intensely to storm events-more so than then would be observed in a less urbanized landscape. The rapid pulse of water that is routed to streams during precipitation events can degrade the physical structure of the channel and alter water quality and habitat availability. To manage these common urban stream issues, agencies have been seeking alternative ways of restoring and enhancing resilience in urban stream networks within the constraints of existing infrastructure. One potential strategy may be to support beaver recolonization of urban streams. This is because beaver dam building activity has been found to attenuate streamflow in areas that have experienced minimal human impact. Currently, however, no studies have been published that examine how beaver dams affect stream flow in altered urban systems. This study seeks to determine if the presence of beaver dams and ponds in urban stream reaches in the Tualatin River basin, Oregon, modifies the stream’s response to storm events. Continuous surface water levels are being collected upstream and downstream of two beaver affected reaches in order to determine how the presence of dams and ponds affect the flow regime, and whether this more closely resembles a less degraded state. Close

• 16. [Article] Scenario Development and Analysis of Freshwater Ecosystem Services under Land Cover and Climate Change in the Tualatin and Yamhill River Basins, Oregon

  Humans make decisions within ecosystems to enhance their well-being, but choices can lead to unintended consequences. The ecosystem services (ES) approach supports decision-making that considers all environmental ...

  Citation × Citation Citation Abstract Copy Title: Scenario Development and Analysis of Freshwater Ecosystem Services under Land Cover and Climate Change in the Tualatin and Yamhill River Basins, Oregon Author: Hoyer, Robert Wesley Year: 2013 Humans make decisions within ecosystems to enhance their well-being, but choices can lead to unintended consequences. The ecosystem services (ES) approach supports decision-making that considers all environmental goods and services. Many challenges remain in the implementation of the ES approach like how specific ES vary through space and time. We address this research problem using the Tualatin and Yamhill river basins in northwestern Oregon as a study area. Freshwater ES are quantified and mapped with the spatially-explicit ES modeling tool, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). In chapter II, we develop a simple urban land cover change modeling approach with selected stakeholder input. The products of this analysis are used in part to answer the question of how the freshwater ES of water yield, nutrient retention, and sediment retention will change in the future, and how their distribution potentially will change? In chapter III, these ES are modeled in InVEST using the land cover scenarios and three downscaled global climate models. The base period is 1981 to 2010 and the future period is 2036 to 2065. The models are calibrated to empirical estimates, and display different sensitivities to inputs. Water yield increases with higher rainfall but decreases with the highest temperature scenario. Nutrient export and retention estimates are positively correlated. In the Tualatin basin, more urban lands generally lead to increases in nutrient exports and retention. The effect is reversed in the Yamhill basin from much larger agricultural exports. Sediment exports and retention increase with higher winter rainfall but are negatively spatially correlated due to topographic effects. Simulation of a landscape scale installation of riparian buffers leads to decreases in exports and increases in retention. The distribution of the provision of freshwater ES remains unchanged throughout the scenarios. With few parameters in each InVEST model, all display a high degree of sensitivity. Parameterization is subject to high uncertainty even with calibrated values. We discuss the assumptions and limitations of InVEST's freshwater models. The spatially explicit nature of InVEST is its main advantage. This work coupled with other analyses in the study area can facilitate the identification of tradeoffs amongst ES leading to better ecosystem management. Title: Scenario Development and Analysis of Freshwater Ecosystem Services under Land Cover and Climate Change in the Tualatin and Yamhill River Basins, Oregon Author: Hoyer, Robert Wesley Year: 2013 Humans make decisions within ecosystems to enhance their well-being, but choices can lead to unintended consequences. The ecosystem services (ES) approach supports decision-making that considers all environmental goods and services. Many challenges remain in the implementation of the ES approach like how specific ES vary through space and time. We address this research problem using the Tualatin and Yamhill river basins in northwestern Oregon as a study area. Freshwater ES are quantified and mapped with the spatially-explicit ES modeling tool, Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST). In chapter II, we develop a simple urban land cover change modeling approach with selected stakeholder input. The products of this analysis are used in part to answer the question of how the freshwater ES of water yield, nutrient retention, and sediment retention will change in the future, and how their distribution potentially will change? In chapter III, these ES are modeled in InVEST using the land cover scenarios and three downscaled global climate models. The base period is 1981 to 2010 and the future period is 2036 to 2065. The models are calibrated to empirical estimates, and display different sensitivities to inputs. Water yield increases with higher rainfall but decreases with the highest temperature scenario. Nutrient export and retention estimates are positively correlated. In the Tualatin basin, more urban lands generally lead to increases in nutrient exports and retention. The effect is reversed in the Yamhill basin from much larger agricultural exports. Sediment exports and retention increase with higher winter rainfall but are negatively spatially correlated due to topographic effects. Simulation of a landscape scale installation of riparian buffers leads to decreases in exports and increases in retention. The distribution of the provision of freshwater ES remains unchanged throughout the scenarios. With few parameters in each InVEST model, all display a high degree of sensitivity. Parameterization is subject to high uncertainty even with calibrated values. We discuss the assumptions and limitations of InVEST's freshwater models. The spatially explicit nature of InVEST is its main advantage. This work coupled with other analyses in the study area can facilitate the identification of tradeoffs amongst ES leading to better ecosystem management. Close

• 17. [Article] Physical, Chemical and Biological Assessment of Yoncalla Log Ponds

  The Yoncalla Log Ponds are a series of four ponds located in within the city limits of the town in Yoncalla in northern Douglas County, Oregon. The ponds were created in stages between the late 1930s and ...

  Citation × Citation Citation Abstract Copy Title: Physical, Chemical and Biological Assessment of Yoncalla Log Ponds Author: Miller, Rich, Sytsma, Mark D., Strecker, Angela L. Year: 2014 The Yoncalla Log Ponds are a series of four ponds located in within the city limits of the town in Yoncalla in northern Douglas County, Oregon. The ponds were created in stages between the late 1930s and the 1950s and used for log storage through the 1970s (North Douglas Betterment 2014). North Douglas Betterment purchased the land surrounding the ponds and contracted with the Center for Lakes and Reservoirs at Portland State University to assess the current morphometry, vegetation and water quality status of the ponds and provide recommendations for management of the aquatic vegetation. The scope of this document covers the current status assessment of the ponds using data collected from June 2013 through May 2014. Title: Physical, Chemical and Biological Assessment of Yoncalla Log Ponds Author: Miller, Rich, Sytsma, Mark D., Strecker, Angela L. Year: 2014 The Yoncalla Log Ponds are a series of four ponds located in within the city limits of the town in Yoncalla in northern Douglas County, Oregon. The ponds were created in stages between the late 1930s and the 1950s and used for log storage through the 1970s (North Douglas Betterment 2014). North Douglas Betterment purchased the land surrounding the ponds and contracted with the Center for Lakes and Reservoirs at Portland State University to assess the current morphometry, vegetation and water quality status of the ponds and provide recommendations for management of the aquatic vegetation. The scope of this document covers the current status assessment of the ponds using data collected from June 2013 through May 2014. Close

• 18. [Article] Convergent Surface Water Distributions in U.S. Cities

  Earth's surface is rapidly urbanizing, resulting in dramatic changes in the abundance, distribution and character of surface water features in urban landscapes. However,the scope and consequences of surface ...

  Citation × Citation Citation Abstract Copy Title: Convergent Surface Water Distributions in U.S. Cities Author: Steele, Meredith K., Heffernan, James B., Bettez, Neil D., Cavender-Bares, Jeannine, Groffman, Peter M., Grove, J. Morgan, Hall, Sharon J., Hobbie, Sarah E., Larson, Kelli L., Morse, Jennifer L., Neill, Christopher, Nelson, Kristen C., O'Neil-Dunne, Jarlath, Ogden, Laura A., Pataki, Diane E., Polsky, Colin, Chowdhury, Rinku Roy Year: 2014 Earth's surface is rapidly urbanizing, resulting in dramatic changes in the abundance, distribution and character of surface water features in urban landscapes. However,the scope and consequences of surface water redistribution at broad spatialscales are not well understood. We hypothesized that urbanization would lead to convergent surface water abundance and distribution: in other words, cities will gain or lose water such that they become more similar to each other than are their surrounding natural landscapes. Using a database of more than 1 million water bodies and 1 million km of streams, we compared the surface water of 100 US cities with their surrounding undeveloped land. We evaluated differences in areal ( A) and numeric densities ( N) of water bodies (lakes, wetlands, and so on), the morphological characteristics of water bodies (size), and the density ( D) of surface flow channels (that is, streams and rivers). The variance of urban A, N, and D across the 100 MSAs decreased, by 89, 25, and 71%, respectively, compared to undeveloped land. These data show that many cities are surface water poor relative to undeveloped land; however, in drier landscapesurbanization increases the occurrence of surface water. This convergence pattern strengthened with development intensity, such that high intensityurban development had an areal water body density 98% less than undeveloped lands. Urbanization appears to drive the convergence of hydrological features across the US, such that surface water distributions of cities are more similar to each other than to their surrounding landscapes. Title: Convergent Surface Water Distributions in U.S. Cities Author: Steele, Meredith K., Heffernan, James B., Bettez, Neil D., Cavender-Bares, Jeannine, Groffman, Peter M., Grove, J. Morgan, Hall, Sharon J., Hobbie, Sarah E., Larson, Kelli L., Morse, Jennifer L., Neill, Christopher, Nelson, Kristen C., O'Neil-Dunne, Jarlath, Ogden, Laura A., Pataki, Diane E., Polsky, Colin, Chowdhury, Rinku Roy Year: 2014 Earth's surface is rapidly urbanizing, resulting in dramatic changes in the abundance, distribution and character of surface water features in urban landscapes. However,the scope and consequences of surface water redistribution at broad spatialscales are not well understood. We hypothesized that urbanization would lead to convergent surface water abundance and distribution: in other words, cities will gain or lose water such that they become more similar to each other than are their surrounding natural landscapes. Using a database of more than 1 million water bodies and 1 million km of streams, we compared the surface water of 100 US cities with their surrounding undeveloped land. We evaluated differences in areal ( A) and numeric densities ( N) of water bodies (lakes, wetlands, and so on), the morphological characteristics of water bodies (size), and the density ( D) of surface flow channels (that is, streams and rivers). The variance of urban A, N, and D across the 100 MSAs decreased, by 89, 25, and 71%, respectively, compared to undeveloped land. These data show that many cities are surface water poor relative to undeveloped land; however, in drier landscapesurbanization increases the occurrence of surface water. This convergence pattern strengthened with development intensity, such that high intensityurban development had an areal water body density 98% less than undeveloped lands. Urbanization appears to drive the convergence of hydrological features across the US, such that surface water distributions of cities are more similar to each other than to their surrounding landscapes. Close

• 19. [Article] Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife Refuge

  This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat ...

  Citation × Citation Citation Abstract Copy Title: Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife Refuge Author: Blackmore, Debra Sue Year: 2016 This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent decades; however, scientific studies have rarely addressed hydrologic connectivity and hydrologic permanence, in spite of the documented importance of these properties. Research steps were designed to be straightforward for easy repeatability: 1) locate sample sites, 2) predict wetness with water indices, 3) estimate wetness with soil samples from the field, 4) validate the index predictions against the soil samples from the field, and 5) in the demonstration step, estimate hydrologic connectivity and hydrological permanence. Results indicate that both indices predicted the presence of large, open water features with clarity; that dry conditions were predicted by MNDWI with more subtle differentiation; and that NDWI results seem more sensitive to sites with vegetation. Use of this low-cost method to discover patterns of surface moisture in the landscape could directly improve the ability to manage wetland environments. Title: Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife Refuge Author: Blackmore, Debra Sue Year: 2016 This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent decades; however, scientific studies have rarely addressed hydrologic connectivity and hydrologic permanence, in spite of the documented importance of these properties. Research steps were designed to be straightforward for easy repeatability: 1) locate sample sites, 2) predict wetness with water indices, 3) estimate wetness with soil samples from the field, 4) validate the index predictions against the soil samples from the field, and 5) in the demonstration step, estimate hydrologic connectivity and hydrological permanence. Results indicate that both indices predicted the presence of large, open water features with clarity; that dry conditions were predicted by MNDWI with more subtle differentiation; and that NDWI results seem more sensitive to sites with vegetation. Use of this low-cost method to discover patterns of surface moisture in the landscape could directly improve the ability to manage wetland environments. Close

• 20. [Article] The Impact of Fine Sediment on Stream Macroinvertebrates in Urban and Rural Oregon Streams

  Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial ...

  Citation × Citation Citation Abstract Copy Title: The Impact of Fine Sediment on Stream Macroinvertebrates in Urban and Rural Oregon Streams Author: Hoy, Raymond S. Year: 2001 Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial space in the substratum, which may have adverse effects on stream biota. A field survey was conducted in Oregon urban and non-urban basins to investigate the relationship between fine sediments and stream macroinvertebrates. Physical, chemical, and biological data were collected from 59 stream sites in two urban and two rural streams. The stream sites fulfilled a continuous sediment gradient, which ranged from a low of 2% of fine sediment in the substrate to a high of 64% with an average of 22%. The % fines, in Clear Creek (rural basin) was significantly lower than in the urban basins (Johnson Creek and Tryon Creek) (p=0.005). Johnson Creek (mean=23%) had approximately three times more fine sediment than Clear Creek (mean=7%), while Tryon Creek (mean=32%) had nearly five times as much fine sediment as Clear Creek. EPT taxa richness was significantly higher in both rural streams than in both urban streams (p0.05). For example, regression analysis of EPT taxa richness vs. % fine sediments displayed a coefficient of determination (r2) value of 0.2. Other macro invertebrates metrics displayed similar patterns. The lack of significant correlations may be due to the cumulative effect of basin-wide "historical land use past". Past land use activity may have resulted in long-term reductions of sensitive taxa in the basin taxa pool and efforts to improve local habitats may not be quickly colonized by pollution sensitive taxa. Long-term degradation to the urban streams resulted in a relatively homogenous assemblage of macro invertebrates, which may have confounded the quantitative relationship between sediments and macroinvertebrates. This study suggests there is a clear difference between urban and non-urban streams in terms of macro invertebrates, which may be likely due to sediments, but the quantitative relationship between fine sediments and macro invertebrates is weak. Title: The Impact of Fine Sediment on Stream Macroinvertebrates in Urban and Rural Oregon Streams Author: Hoy, Raymond S. Year: 2001 Urbanization, often characterized by high impervious surface area, can result in excessive inputs of fine sediments into urban streams. Excessive fine sediments can blanket the stream bed filling the interstitial space in the substratum, which may have adverse effects on stream biota. A field survey was conducted in Oregon urban and non-urban basins to investigate the relationship between fine sediments and stream macroinvertebrates. Physical, chemical, and biological data were collected from 59 stream sites in two urban and two rural streams. The stream sites fulfilled a continuous sediment gradient, which ranged from a low of 2% of fine sediment in the substrate to a high of 64% with an average of 22%. The % fines, in Clear Creek (rural basin) was significantly lower than in the urban basins (Johnson Creek and Tryon Creek) (p=0.005). Johnson Creek (mean=23%) had approximately three times more fine sediment than Clear Creek (mean=7%), while Tryon Creek (mean=32%) had nearly five times as much fine sediment as Clear Creek. EPT taxa richness was significantly higher in both rural streams than in both urban streams (p0.05). For example, regression analysis of EPT taxa richness vs. % fine sediments displayed a coefficient of determination (r2) value of 0.2. Other macro invertebrates metrics displayed similar patterns. The lack of significant correlations may be due to the cumulative effect of basin-wide "historical land use past". Past land use activity may have resulted in long-term reductions of sensitive taxa in the basin taxa pool and efforts to improve local habitats may not be quickly colonized by pollution sensitive taxa. Long-term degradation to the urban streams resulted in a relatively homogenous assemblage of macro invertebrates, which may have confounded the quantitative relationship between sediments and macroinvertebrates. This study suggests there is a clear difference between urban and non-urban streams in terms of macro invertebrates, which may be likely due to sediments, but the quantitative relationship between fine sediments and macro invertebrates is weak. Close