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• 1. [Article] Stream-Associated Amphibian Habitat Assessment in the Portland-Vancouver Metropolitan Region

  This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may ...

  Citation × Citation Citation Abstract Copy Title: Stream-Associated Amphibian Habitat Assessment in the Portland-Vancouver Metropolitan Region Author: Dietrich, Andrew Evans Year: 2012 This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may dramatically affect the ecology of neighboring aquatic systems. It was hypothesized that lotic amphibians would be negatively associated with greater amounts of landscape development and positively associated with forested area within the surrounding watershed. Thirty-seven 1st-3rd order streams were sampled between June 21st and September 21st in 2011. Streams potentially providing adequate habitat for stream-obligate amphibians were randomly selected. Amphibians were surveyed along 30-meter stream transects using an active-cover search (ACS). Environmental variables associated with development in surrounding landscapes were measured in situ. GIS delineation was conducted to define landscape-scale variables at stratified distances from riparian networks up-stream of each site via the utilization of the 2006 NLCD dataset and a finer-scale, regional dataset compiled by the Institute for Natural Resources (INR). Amphibians were detected at seventeen of the thirty-seven sampled streams. The most commonly detected species were Dicamptadon tenebrosus, Plethadon vehiculum and Plethadon dunni. Streams where amphibians were observed had lower average water temperature and conductivity, coarser stream substrate and were located on public property more often than streams where no amphibians were detected. Landscape variables were most significant to amphibians within 100 and 200 meters of the upstream stream network. Occupancy of a site by facultative species was best explained by the proportion of mixed forest in the surrounding watershed (R2=0.343, p<0.001). Occupancy of a stream by obligate species was best predicted by measurements of water quality and in-stream cover (Water Temperature: R2=0.275, p<0.001; Water Conductivity: R2=0.248, p<0.001; Cover: R2=0.323, p<0.001). Occupancy of stream refugia by all observed amphibians was positively influenced by higher percentages of forest cover and lower percentages of urban development and herbaceous vegetation in the surrounding watershed. Results of this study indicate that urban refugia must contain adequate riparian forest area, coarse stream substrate and clean, cool water to sustain stream-amphibian communities. Protection of remnant forested headwater stream networks is essential to the conservation of lotic amphibians in this urbanized region. Title: Stream-Associated Amphibian Habitat Assessment in the Portland-Vancouver Metropolitan Region Author: Dietrich, Andrew Evans Year: 2012 This study assessed the influence of landscape development on stream-associated amphibians in forested riparian areas within the Portland-Vancouver metropolitan region. Human alteration of landscapes may dramatically affect the ecology of neighboring aquatic systems. It was hypothesized that lotic amphibians would be negatively associated with greater amounts of landscape development and positively associated with forested area within the surrounding watershed. Thirty-seven 1st-3rd order streams were sampled between June 21st and September 21st in 2011. Streams potentially providing adequate habitat for stream-obligate amphibians were randomly selected. Amphibians were surveyed along 30-meter stream transects using an active-cover search (ACS). Environmental variables associated with development in surrounding landscapes were measured in situ. GIS delineation was conducted to define landscape-scale variables at stratified distances from riparian networks up-stream of each site via the utilization of the 2006 NLCD dataset and a finer-scale, regional dataset compiled by the Institute for Natural Resources (INR). Amphibians were detected at seventeen of the thirty-seven sampled streams. The most commonly detected species were Dicamptadon tenebrosus, Plethadon vehiculum and Plethadon dunni. Streams where amphibians were observed had lower average water temperature and conductivity, coarser stream substrate and were located on public property more often than streams where no amphibians were detected. Landscape variables were most significant to amphibians within 100 and 200 meters of the upstream stream network. Occupancy of a site by facultative species was best explained by the proportion of mixed forest in the surrounding watershed (R2=0.343, p<0.001). Occupancy of a stream by obligate species was best predicted by measurements of water quality and in-stream cover (Water Temperature: R2=0.275, p<0.001; Water Conductivity: R2=0.248, p<0.001; Cover: R2=0.323, p<0.001). Occupancy of stream refugia by all observed amphibians was positively influenced by higher percentages of forest cover and lower percentages of urban development and herbaceous vegetation in the surrounding watershed. Results of this study indicate that urban refugia must contain adequate riparian forest area, coarse stream substrate and clean, cool water to sustain stream-amphibian communities. Protection of remnant forested headwater stream networks is essential to the conservation of lotic amphibians in this urbanized region. Close

• 2. [Article] Riparian Shade Assessment and Restoration Priorities Analysis in the Damascus Urban Growth Boundary Expansion Area

  An important component of progressive urban planning is the protection and restoration of riparian environments, particularly in the Pacific Northwest where increasing stream temperatures threaten the ...

  Citation × Citation Citation Abstract Copy Title: Riparian Shade Assessment and Restoration Priorities Analysis in the Damascus Urban Growth Boundary Expansion Area Author: Leferink, Robin K. Year: 2007 An important component of progressive urban planning is the protection and restoration of riparian environments, particularly in the Pacific Northwest where increasing stream temperatures threaten the survival of endangered salmonids and other cold-water biota. Restoration projects are often led by watershed councils or other grassroots organizations with limited resources, and it is essential that these groups have an efficient and effective approach to determine priority areas where their efforts can be directed to achieve the greatest ecological benefit. The purpose of this project was to quantify existing riparian shade levels and identify priority reaches for shade restoration on Clackamas River basin streams in the Damascus area expansion of the Portland, Oregon urban growth boundary. Additionally, potential errors in the Metro Regional Land Information System (RLIS) Lite geographic information system (GIS) coverage of the area’s streams were identified and corrected where possible. Riparian shade levels were quantified through interpretation of digital aerial photographs using GIS. At the start of the shade analysis six 50 m reaches in the study area were surveyed using a spherical densiometer to calibrate the aerial photo interpretation. Following the analysis, the method accuracy was assessed by comparing GIS-derived shade classes with field data from 25 sites in the study area that were surveyed in 2003. Stream reaches were identified and prioritized for restoration based on riparian shade level, presence or absence of late-summer flow (as determined through field investigations), and GISevaluated stream aspect (i.e. the direction of stream flow). Generally, the headwaters were found to have less shade than the downstream areas and many of the headwater reaches were identified as the highest restoration priority. Of the 60.5 km of streams assessed in the riparian shade analysis, 24.7 km were identified as potential restoration reaches based on shade levels and late-summer flow conditions. These 24.7 km were further broken into five priority ranks, with 4.1 km of stream reaches assigned to the highest shade restoration priority class. Potential errors in the GIS stream coverage were identified in conjunction with the riparian shade assessment. Where possible, these errors were corrected based on the aerial photographs. Although in many cases access was limited, a total of 18 site visits were made to verify stream locations. The results of this watershed-scale restoration priorities analysis are being used by Clackamas River Basin Council and others to guide restoration planning in the new urban area. While focusing on the high priority stream reaches identified, restoration managers will also need to consider reach-scale factors including land use plans, riparian continuity, parcel size, and landowner cooperation in the final selection of restoration sites. The GIS stream layer corrections were provided to Metro and to the City of Damascus for use in their 2007 natural resource inventory. Title: Riparian Shade Assessment and Restoration Priorities Analysis in the Damascus Urban Growth Boundary Expansion Area Author: Leferink, Robin K. Year: 2007 An important component of progressive urban planning is the protection and restoration of riparian environments, particularly in the Pacific Northwest where increasing stream temperatures threaten the survival of endangered salmonids and other cold-water biota. Restoration projects are often led by watershed councils or other grassroots organizations with limited resources, and it is essential that these groups have an efficient and effective approach to determine priority areas where their efforts can be directed to achieve the greatest ecological benefit. The purpose of this project was to quantify existing riparian shade levels and identify priority reaches for shade restoration on Clackamas River basin streams in the Damascus area expansion of the Portland, Oregon urban growth boundary. Additionally, potential errors in the Metro Regional Land Information System (RLIS) Lite geographic information system (GIS) coverage of the area’s streams were identified and corrected where possible. Riparian shade levels were quantified through interpretation of digital aerial photographs using GIS. At the start of the shade analysis six 50 m reaches in the study area were surveyed using a spherical densiometer to calibrate the aerial photo interpretation. Following the analysis, the method accuracy was assessed by comparing GIS-derived shade classes with field data from 25 sites in the study area that were surveyed in 2003. Stream reaches were identified and prioritized for restoration based on riparian shade level, presence or absence of late-summer flow (as determined through field investigations), and GISevaluated stream aspect (i.e. the direction of stream flow). Generally, the headwaters were found to have less shade than the downstream areas and many of the headwater reaches were identified as the highest restoration priority. Of the 60.5 km of streams assessed in the riparian shade analysis, 24.7 km were identified as potential restoration reaches based on shade levels and late-summer flow conditions. These 24.7 km were further broken into five priority ranks, with 4.1 km of stream reaches assigned to the highest shade restoration priority class. Potential errors in the GIS stream coverage were identified in conjunction with the riparian shade assessment. Where possible, these errors were corrected based on the aerial photographs. Although in many cases access was limited, a total of 18 site visits were made to verify stream locations. The results of this watershed-scale restoration priorities analysis are being used by Clackamas River Basin Council and others to guide restoration planning in the new urban area. While focusing on the high priority stream reaches identified, restoration managers will also need to consider reach-scale factors including land use plans, riparian continuity, parcel size, and landowner cooperation in the final selection of restoration sites. The GIS stream layer corrections were provided to Metro and to the City of Damascus for use in their 2007 natural resource inventory. Close

• 3. [Article] Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed

  Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative ...

  Citation × Citation Citation Abstract Copy Title: Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed Author: Hong, Change-Yu, Chung, Eun-Sung Year: 2016 Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative governance definitely requires an active participatory decision-making process that reflects citizens’ preferences. Citizen preference also tends to substantially change with life pattern and life quality. These shifts can be caused by slight variations in both social priorities and personal preferences for SWM. Therefore, collaborative water governance must be frequently renewed in response to citizens’ values through the participatory framework. The An’yang Stream in South Korea is generally regarded as a representative urban stream restoration case that has been successfully led by collaborative governance. By conducting individual surveys with citizens on-site, this study addresses how citizens’ preferences of the stream’s management have changed between 2005 and 2015. In addition, this study used three quantitative hydrologic vulnerability indices: potential flood damage (PFD), potential streamflow depletion (PSD), and potential water quality deterioration (PWQD). They can spatially quantify citizen preference using the Analytic Hierarchy Process (AHP), which can systematically derive citizens’ subjective relative-weighted preferences. In the end, this study identified critical differences in priorities in regard to vulnerable areas between in 2005 and in 2015. Title: Temporal Variations of Citizens’ Demands on Flood Damage Mitigation, Streamflow Quantity and Quality in the Korean Urban Watershed Author: Hong, Change-Yu, Chung, Eun-Sung Year: 2016 Sustainable watershed management (SWM) can be achieved through recognition and reflection upon the values of citizens. Collaborative governance consisting of citizens is crucial for successful SWM. Collaborative governance definitely requires an active participatory decision-making process that reflects citizens’ preferences. Citizen preference also tends to substantially change with life pattern and life quality. These shifts can be caused by slight variations in both social priorities and personal preferences for SWM. Therefore, collaborative water governance must be frequently renewed in response to citizens’ values through the participatory framework. The An’yang Stream in South Korea is generally regarded as a representative urban stream restoration case that has been successfully led by collaborative governance. By conducting individual surveys with citizens on-site, this study addresses how citizens’ preferences of the stream’s management have changed between 2005 and 2015. In addition, this study used three quantitative hydrologic vulnerability indices: potential flood damage (PFD), potential streamflow depletion (PSD), and potential water quality deterioration (PWQD). They can spatially quantify citizen preference using the Analytic Hierarchy Process (AHP), which can systematically derive citizens’ subjective relative-weighted preferences. In the end, this study identified critical differences in priorities in regard to vulnerable areas between in 2005 and in 2015. Close

• 4. [Article] Introduction to Common Native and Potential Invasive Freshwater Plants in Alaska

  Freshwater aquatic plants are found in most lakes and rivers in Alaska. They range from tiny floating plants that can form mats on a lake surface to emergent plants growing two meters above the water. ...

  Citation × Citation Citation Abstract Copy Title: Introduction to Common Native and Potential Invasive Freshwater Plants in Alaska Author: Morgan, Vanessa Howard, Sytsma, Mark Year: 2009 Freshwater aquatic plants are found in most lakes and rivers in Alaska. They range from tiny floating plants that can form mats on a lake surface to emergent plants growing two meters above the water. Aquatic plants are an important part of freshwater environments. They provide food and shelter for a wide variety of insects, fish, mammals, and birds; stabilize shorelines; and form an important link in nutrient cycles. To date, Alaska has had relatively few problems with invasive, non-native aquatic plants. However, invasive aquatic plants pose an increasing threat to human safety and the integrity of native aquatic communities. Actions taken to detect and prevent the introduction and spread of invasive aquatic plants in Alaska are necessary in order to avoid the environmental and economic harm invasive plants have caused in other parts of the United States. The primary purposes of this manual are to aide the identification of freshwater aquatic plants that are likely to be seen in Alaska’s lakes, streams, bogs and marshes; and to help prevent the spread of harmful invasive plants. This manual was written for people who do not necessarily have a scientific background, but it also should be useful for professionals who need assistance in identifying common aquatic species. Title: Introduction to Common Native and Potential Invasive Freshwater Plants in Alaska Author: Morgan, Vanessa Howard, Sytsma, Mark Year: 2009 Freshwater aquatic plants are found in most lakes and rivers in Alaska. They range from tiny floating plants that can form mats on a lake surface to emergent plants growing two meters above the water. Aquatic plants are an important part of freshwater environments. They provide food and shelter for a wide variety of insects, fish, mammals, and birds; stabilize shorelines; and form an important link in nutrient cycles. To date, Alaska has had relatively few problems with invasive, non-native aquatic plants. However, invasive aquatic plants pose an increasing threat to human safety and the integrity of native aquatic communities. Actions taken to detect and prevent the introduction and spread of invasive aquatic plants in Alaska are necessary in order to avoid the environmental and economic harm invasive plants have caused in other parts of the United States. The primary purposes of this manual are to aide the identification of freshwater aquatic plants that are likely to be seen in Alaska’s lakes, streams, bogs and marshes; and to help prevent the spread of harmful invasive plants. This manual was written for people who do not necessarily have a scientific background, but it also should be useful for professionals who need assistance in identifying common aquatic species. Close

• 5. [Article] Calculating the Volume of the May 18, 1980 Eruption of Mount St. Helens

  The May 18, 1980 eruption of Mount St. Helens created a massive amount of sediment and debris, thought to be as much as 5.5 billion cubic yards. This sediment causes infill of river stretches and collects ...

  Citation × Citation Citation Abstract Copy Title: Calculating the Volume of the May 18, 1980 Eruption of Mount St. Helens Author: Wickham, Dâvid Nuñez Year: 2009 The May 18, 1980 eruption of Mount St. Helens created a massive amount of sediment and debris, thought to be as much as 5.5 billion cubic yards. This sediment causes infill of river stretches and collects along levees protecting southwest Washington State. The sediment must be removed to ensure these areas do not flood. The US Army Corps of Engineers (USACOE) is tasked with flood protection for southwest Washington State and the levees protecting the cities of Castle Rock, Lexington, Kelso, and Longview. The Sediment Retention Dam, opened in 1989 is able to filter out larger particulate but fine grain sediment remains in the water column and is transported further down the river. In order to calculate how much sediment remains to be removed Portland State University’s Environmental Sciences and Management program and the USACOE formed a partnership and generated Digital Elevation Models (DEM) from topographic maps made by the United States Geological Survey (USGS). This was accomplished by taking 600 dots per inch (dpi) scanned images of the eruption path, geographically rectifying them in ESRI’s ArcMap software environment, and running Iterative Self-Organizing Data Analysis Technique (ISODATA) Unsupervised Classification utilizing ERDAS Imagine 9.3 software. After the contour lines were extracted from the images we cleaned up the lines in a raster environment, converted the raster to vector lines, and entered elevations. From these contour lines we created the DEM and calculated the volume difference between the pre-eruption 15 minute USGS maps and the 7.5 minute post-eruption quad maps. The volume difference was 7,870,546,345 m3 for Mount St. Helens quads, - 4,335,917,517 m3 for Spirit Lake quads, -220,149,557 m3 for Goat Mtn. in Cougar quads, -3,155,437,891 m3 for Elk Rock quads, and 734,102,545 m3 for Hoffstadt Mtn. in Elk Rock pre quad. These figures indicated a large generation of sediment and debris on the slope north of Mount St. Helens, sediment deposition in the Hoffstadt Mtn. river reach, and erosion in all other areas. The USACOE will use my raw data contour elevation lines to create their own DEMs incorporating stream locations to further refine the data. From this data they hope to extrapolate how much sediment is left and where the sediment deposits are likely to erode from in the future. Title: Calculating the Volume of the May 18, 1980 Eruption of Mount St. Helens Author: Wickham, Dâvid Nuñez Year: 2009 The May 18, 1980 eruption of Mount St. Helens created a massive amount of sediment and debris, thought to be as much as 5.5 billion cubic yards. This sediment causes infill of river stretches and collects along levees protecting southwest Washington State. The sediment must be removed to ensure these areas do not flood. The US Army Corps of Engineers (USACOE) is tasked with flood protection for southwest Washington State and the levees protecting the cities of Castle Rock, Lexington, Kelso, and Longview. The Sediment Retention Dam, opened in 1989 is able to filter out larger particulate but fine grain sediment remains in the water column and is transported further down the river. In order to calculate how much sediment remains to be removed Portland State University’s Environmental Sciences and Management program and the USACOE formed a partnership and generated Digital Elevation Models (DEM) from topographic maps made by the United States Geological Survey (USGS). This was accomplished by taking 600 dots per inch (dpi) scanned images of the eruption path, geographically rectifying them in ESRI’s ArcMap software environment, and running Iterative Self-Organizing Data Analysis Technique (ISODATA) Unsupervised Classification utilizing ERDAS Imagine 9.3 software. After the contour lines were extracted from the images we cleaned up the lines in a raster environment, converted the raster to vector lines, and entered elevations. From these contour lines we created the DEM and calculated the volume difference between the pre-eruption 15 minute USGS maps and the 7.5 minute post-eruption quad maps. The volume difference was 7,870,546,345 m3 for Mount St. Helens quads, - 4,335,917,517 m3 for Spirit Lake quads, -220,149,557 m3 for Goat Mtn. in Cougar quads, -3,155,437,891 m3 for Elk Rock quads, and 734,102,545 m3 for Hoffstadt Mtn. in Elk Rock pre quad. These figures indicated a large generation of sediment and debris on the slope north of Mount St. Helens, sediment deposition in the Hoffstadt Mtn. river reach, and erosion in all other areas. The USACOE will use my raw data contour elevation lines to create their own DEMs incorporating stream locations to further refine the data. From this data they hope to extrapolate how much sediment is left and where the sediment deposits are likely to erode from in the future. Close

• 6. [Article] The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River

  A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the ...

  Citation × Citation Citation Abstract Copy Title: The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River Author: Ahilan, Sangaralingam, Guan, Mingfu, Sleigh, Andrew, Wright, Nigel G., Chang, Heejun Year: 2016 A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km2 (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up to 25% at the downstream. Results also indicated that approximately 20%–30% of sediment from the upstream is deposited on the East Lents floodplain. Furthermore, deposited sediment over the simulated period (1941–2014) is approximately 0.1% of the basin's flood storage capacity; however, the reduction in the storage does not offset the overall flood resilience impact of the flood basin. The sediment conservation at the East Lents flood basin as predicted by the model reduces the annual sediment loading of the Johnson Creek by 1% at the confluence with Willamette River, providing both improved water quality and flood resilience further downstream. Title: The Influence of Floodplain Restoration on Flow and Sediment Dynamics in an Urban River Author: Ahilan, Sangaralingam, Guan, Mingfu, Sleigh, Andrew, Wright, Nigel G., Chang, Heejun Year: 2016 A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km2 (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up to 25% at the downstream. Results also indicated that approximately 20%–30% of sediment from the upstream is deposited on the East Lents floodplain. Furthermore, deposited sediment over the simulated period (1941–2014) is approximately 0.1% of the basin's flood storage capacity; however, the reduction in the storage does not offset the overall flood resilience impact of the flood basin. The sediment conservation at the East Lents flood basin as predicted by the model reduces the annual sediment loading of the Johnson Creek by 1% at the confluence with Willamette River, providing both improved water quality and flood resilience further downstream. Close

• 7. [Article] Comparative Standards for Intensive Livestock Operations in Canada, Mexico, and the United States

  Livestock farming has been transformed in the past twenty years from a business dominated by relatively small producers to one dominated by large facilities raising thousands of animals. A side effect ...

  Citation × Citation Citation Abstract Copy Title: Comparative Standards for Intensive Livestock Operations in Canada, Mexico, and the United States Author: Speir, Jerry, Bowden, Marie-Ann, Ervin, David E., McElfish, Jim, Espejo, Rosario P., Whitehouse, Tim, Carpentier, Chantal L. Year: 2003 Livestock farming has been transformed in the past twenty years from a business dominated by relatively small producers to one dominated by large facilities raising thousands of animals. A side effect of this development has been a new set of environmental concerns unique to this industry. While regulation of livestock agriculture has historically been a state/provincial and local matter, governments from the local to the federal level have found themselves grappling with the issues created by these new, concentrated facilities. This Report surveys the current environmental requirements for "intensive livestock operations" (ILOs) in the United States, Mexico and Canada. The Report draws conclusions about current regulatory regimes and makes recommendations on the management of environmental issues associated with ILOs. Title: Comparative Standards for Intensive Livestock Operations in Canada, Mexico, and the United States Author: Speir, Jerry, Bowden, Marie-Ann, Ervin, David E., McElfish, Jim, Espejo, Rosario P., Whitehouse, Tim, Carpentier, Chantal L. Year: 2003 Livestock farming has been transformed in the past twenty years from a business dominated by relatively small producers to one dominated by large facilities raising thousands of animals. A side effect of this development has been a new set of environmental concerns unique to this industry. While regulation of livestock agriculture has historically been a state/provincial and local matter, governments from the local to the federal level have found themselves grappling with the issues created by these new, concentrated facilities. This Report surveys the current environmental requirements for "intensive livestock operations" (ILOs) in the United States, Mexico and Canada. The Report draws conclusions about current regulatory regimes and makes recommendations on the management of environmental issues associated with ILOs. Close