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• 1. [Article] A Geospatial Tool for Wetland Prioritization at the Watershed Scale

  There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential ...

  Citation × Citation Citation Abstract Copy Title: A Geospatial Tool for Wetland Prioritization at the Watershed Scale Author: Blackmore, Debra Sue, Chang, Heejun Year: 2015 There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential of selected ecosystem functions for freshwater wetlands within a watershed using widely available geospatial data. We developed four functions to estimate 1) flood storage, 2) late season flow, 3) sediment retention and 4) temperature control in four pilot watersheds in Oregon (Tualatin, Coquille, Upper Grande Ronde and Sprague). These watersheds are geographically separated from each other representing diverse ecoregion environments. Spatial analysis and geographic information system (GIS) were designed for maximum re-use, based on publicly-available data, commonly-used software, semi-automated techniques and wetland characterizations that attempt to capture fundamental wetland processes. Our data sources include 30-meter digital elevation models, NRCS soil survey extracts, USGS National Land Cover Data, USGS HUC8 boundaries (polygons) and statewide wetland delineations (polygons) processed within ArcGIS 10.2 and Python 2.7.5 software. Model parameters were compiled using multiple proxy values for size, slope, aspect, proximity, flow path distance, hydrologic gradient, shade, and soil characteristics. WPT characterizations emphasize the multi-faceted value of freshwater wetlands, relating potential within a watershed as well as providing model-based characterizations between watersheds. Our wetland prioritization tool (WPT) provides useful information to estimate and compare the relative potential for selected wetland functions, thereby improving success in wetland conservation, restoration, and mitigation efforts. Title: A Geospatial Tool for Wetland Prioritization at the Watershed Scale Author: Blackmore, Debra Sue, Chang, Heejun Year: 2015 There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential of selected ecosystem functions for freshwater wetlands within a watershed using widely available geospatial data. We developed four functions to estimate 1) flood storage, 2) late season flow, 3) sediment retention and 4) temperature control in four pilot watersheds in Oregon (Tualatin, Coquille, Upper Grande Ronde and Sprague). These watersheds are geographically separated from each other representing diverse ecoregion environments. Spatial analysis and geographic information system (GIS) were designed for maximum re-use, based on publicly-available data, commonly-used software, semi-automated techniques and wetland characterizations that attempt to capture fundamental wetland processes. Our data sources include 30-meter digital elevation models, NRCS soil survey extracts, USGS National Land Cover Data, USGS HUC8 boundaries (polygons) and statewide wetland delineations (polygons) processed within ArcGIS 10.2 and Python 2.7.5 software. Model parameters were compiled using multiple proxy values for size, slope, aspect, proximity, flow path distance, hydrologic gradient, shade, and soil characteristics. WPT characterizations emphasize the multi-faceted value of freshwater wetlands, relating potential within a watershed as well as providing model-based characterizations between watersheds. Our wetland prioritization tool (WPT) provides useful information to estimate and compare the relative potential for selected wetland functions, thereby improving success in wetland conservation, restoration, and mitigation efforts. Close

• 2. [Article] Watershed Response to Climate Change and Fire-Burns in the Upper Umatilla River Basin, USA

  This study analyzed watershed response to climate change and forest fire impacts in the upper Umatilla River Basin (URB), Oregon, using the precipitation runoff modeling system. Ten global climate models ...

  Citation × Citation Citation Abstract Copy Title: Watershed Response to Climate Change and Fire-Burns in the Upper Umatilla River Basin, USA Author: Yazzie, Kimberly Crystal, Chang, Heejun Year: 2017 This study analyzed watershed response to climate change and forest fire impacts in the upper Umatilla River Basin (URB), Oregon, using the precipitation runoff modeling system. Ten global climate models using Coupled Intercomparison Project Phase 5 experiments with Representative Concentration Pathways (RCP) 4.5 and 8.5 were used to simulate the effects of climate and fire-burns on runoff behavior throughout the 21st century. We observed the center timing (CT) of flow, seasonal flows, snow water equivalent (SWE) and basin recharge. In the upper URB, hydrologic regime shifts from a snow-rain-dominated to rain-dominated basin. Ensemble mean CT occurs 27 days earlier in RCP 4.5 and 33 days earlier in RCP 8.5, in comparison to historic conditions (1980s) by the end of the 21st century. After forest cover reduction in the 2080s, CT occurs 35 days earlier in RCP 4.5 and 29 days earlier in RCP 8.5. The difference in mean CT after fire-burns may be due to projected changes in the individual climate model. Winter flow is projected to decline after forest cover reduction in the 2080s by 85% and 72% in RCP 4.5 and RCP 8.5, in comparison to 98% change in ensemble mean winter flows in the 2080s before forest cover reduction. The ratio of ensemble mean snow water equivalent to precipitation substantially decreases by 81% and 91% in the 2050s and 2080s before forest cover reduction and a decrease of 90% in RCP 4.5 and 99% in RCP 8.5 in the 2080s after fire-burns. Mean basin recharge is 10% and 14% lower in the 2080s before fire-burns and after fire-burns, and it decreases by 13% in RCP 4.5 and decreases 22% in RCP 8.5 in the 2080s in comparison to historical conditions. Mixed results for recharge after forest cover reduction suggest that an increase may be due to the size of burned areas, decreased canopy interception and less evaporation occurring at the watershed surface, increasing the potential for infiltration. The effects of fire on the watershed system are strongly indicated by a significant increase in winter seasonal flows and a slight reduction in summer flows. Findings from this study may improve adaptive management of water resources, flood control and the effects of fire on a watershed system. Title: Watershed Response to Climate Change and Fire-Burns in the Upper Umatilla River Basin, USA Author: Yazzie, Kimberly Crystal, Chang, Heejun Year: 2017 This study analyzed watershed response to climate change and forest fire impacts in the upper Umatilla River Basin (URB), Oregon, using the precipitation runoff modeling system. Ten global climate models using Coupled Intercomparison Project Phase 5 experiments with Representative Concentration Pathways (RCP) 4.5 and 8.5 were used to simulate the effects of climate and fire-burns on runoff behavior throughout the 21st century. We observed the center timing (CT) of flow, seasonal flows, snow water equivalent (SWE) and basin recharge. In the upper URB, hydrologic regime shifts from a snow-rain-dominated to rain-dominated basin. Ensemble mean CT occurs 27 days earlier in RCP 4.5 and 33 days earlier in RCP 8.5, in comparison to historic conditions (1980s) by the end of the 21st century. After forest cover reduction in the 2080s, CT occurs 35 days earlier in RCP 4.5 and 29 days earlier in RCP 8.5. The difference in mean CT after fire-burns may be due to projected changes in the individual climate model. Winter flow is projected to decline after forest cover reduction in the 2080s by 85% and 72% in RCP 4.5 and RCP 8.5, in comparison to 98% change in ensemble mean winter flows in the 2080s before forest cover reduction. The ratio of ensemble mean snow water equivalent to precipitation substantially decreases by 81% and 91% in the 2050s and 2080s before forest cover reduction and a decrease of 90% in RCP 4.5 and 99% in RCP 8.5 in the 2080s after fire-burns. Mean basin recharge is 10% and 14% lower in the 2080s before fire-burns and after fire-burns, and it decreases by 13% in RCP 4.5 and decreases 22% in RCP 8.5 in the 2080s in comparison to historical conditions. Mixed results for recharge after forest cover reduction suggest that an increase may be due to the size of burned areas, decreased canopy interception and less evaporation occurring at the watershed surface, increasing the potential for infiltration. The effects of fire on the watershed system are strongly indicated by a significant increase in winter seasonal flows and a slight reduction in summer flows. Findings from this study may improve adaptive management of water resources, flood control and the effects of fire on a watershed system. Close

• 3. [Article] Science and Practice of Integrated River Basin Management : Lessons from North and Central American UNESCO-HELP Basins

  The Hydrology for the Environment, Life and Policy (HELP) program, a cross-cutting component of the UNESCO International Hydrological Programme (IHP), has as its goal to facilitate dialogue among hydrologists, ...

  Citation × Citation Citation Abstract Copy Title: Science and Practice of Integrated River Basin Management : Lessons from North and Central American UNESCO-HELP Basins Author: Chang, Heejun, Browning-Aiken, Anne Year: 2010 The Hydrology for the Environment, Life and Policy (HELP) program, a cross-cutting component of the UNESCO International Hydrological Programme (IHP), has as its goal to facilitate dialogue among hydrologists, social and economic scientists, water resource managers, water lawyers, policy experts, and river basin stakeholder communities in setting a research agenda driven by local management and policy issues. HELP seeks to improve the benefits to society by applying the principals of integrated water-resources management to complex, interdisciplinary issues within catchments. This Monograph is the culmination of a workshop held in 2010 in which the managers from the six North American basins (San Pedro, Willamette, Upper Washita, Lake Champlain, Iowa-Cedar, Luquillo) and a Central American basin (Panama Canal), see Figure 1, met to exchange ideas and “lessons learned” in various applications of IWRM within the HELP philosophy. Three major themes were examined: 1. Climate change: Creating watershed resilience 2. Use of social learning in IWRM 3. Knowledge and information management for IWRM Each of these themes is explored in detail and enhanced with case studies of IWRM applications from the participating North and Central American HELP basins. Title: Science and Practice of Integrated River Basin Management : Lessons from North and Central American UNESCO-HELP Basins Author: Chang, Heejun, Browning-Aiken, Anne Year: 2010 The Hydrology for the Environment, Life and Policy (HELP) program, a cross-cutting component of the UNESCO International Hydrological Programme (IHP), has as its goal to facilitate dialogue among hydrologists, social and economic scientists, water resource managers, water lawyers, policy experts, and river basin stakeholder communities in setting a research agenda driven by local management and policy issues. HELP seeks to improve the benefits to society by applying the principals of integrated water-resources management to complex, interdisciplinary issues within catchments. This Monograph is the culmination of a workshop held in 2010 in which the managers from the six North American basins (San Pedro, Willamette, Upper Washita, Lake Champlain, Iowa-Cedar, Luquillo) and a Central American basin (Panama Canal), see Figure 1, met to exchange ideas and “lessons learned” in various applications of IWRM within the HELP philosophy. Three major themes were examined: 1. Climate change: Creating watershed resilience 2. Use of social learning in IWRM 3. Knowledge and information management for IWRM Each of these themes is explored in detail and enhanced with case studies of IWRM applications from the participating North and Central American HELP basins. Close