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Editorial: Innovating A New Knowledge Base For Water Justice Studies: Hydrosocial, Sociohydrology, And Beyond, Melissa Haeffner, Jenia Mukherjee, Rebecca Lave, Jamie Linton, John Ndiritu, Raul Pacheco-Vega, Maria Ruska, Margreet Zwarteveen Mar 2024

Editorial: Innovating A New Knowledge Base For Water Justice Studies: Hydrosocial, Sociohydrology, And Beyond, Melissa Haeffner, Jenia Mukherjee, Rebecca Lave, Jamie Linton, John Ndiritu, Raul Pacheco-Vega, Maria Ruska, Margreet Zwarteveen

Environmental Science and Management Faculty Publications and Presentations

Creating a new knowledge base that centers water justice (Zwarteveen and Boelens, 2014; Sultana, 2018; Wölfle-Hazard, 2022) in hydrosocial and sociohydrology studies involves a broader discussion about why justice matters, how to work toward this goal, and what the implications for research praxis are. The articles in this Research Topic approach different angles of water justice: as law (Fernández and Alba), a social movement (Dame et al.), practice (Pool et al.; Reeves and Bonney), cases of injustice (Caretta et al.), and theory (Krueger and Alba). From this Research Topic, we find that the interrelated concepts of naturecultures and care can …


Long-Term Phosphorus Reduction And Phytoplankton Responses In An Urban Lake (Usa), Yuan Xiao Grund, Yangdong Pan, Mark Rosenkranz, Eugene Foster Feb 2023

Long-Term Phosphorus Reduction And Phytoplankton Responses In An Urban Lake (Usa), Yuan Xiao Grund, Yangdong Pan, Mark Rosenkranz, Eugene Foster

Environmental Science and Management Faculty Publications and Presentations

Eutrophication is one of the primary factors causing harmful cyanobacteria blooms in freshwater lakes. This study investigated the long-term changes in water quality and summer phytoplankton assemblages in Oswego Lake, OR, USA, in relation to phosphorus reduction through hypolimnetic aeration and alum applications. Both water quality and phytoplankton assemblages were sampled biweekly during the summers from 2001 to 2013. The concentrations of total phosphorus, soluble reactive phosphorus, and total nitrogen decreased 66%, 93% and 31%, respectively, in response to the hypolimnetic aeration and alum treatments since 2005. Summer phytoplankton assemblages showed a 62% reduction of cyanobacteria biovolume and a …


Stakeholder Perceptions Of Microplastics Management In Oregon, Maya A. Hurst-Mayr May 2022

Stakeholder Perceptions Of Microplastics Management In Oregon, Maya A. Hurst-Mayr

Student Research Symposium

There is currently no federal policy in the United States that specifically addresses microplastics (MPs) pollution. However, states are beginning to act on this issue; California’s SB 1422 initiates measurement of MPs in drinking water resources and Senate Bill 1263 requires the state to adopt a strategy to reduce the ecological impact of MPs in marine ecosystems. Other West Coast states like Oregon and Washington are expected to follow California’s example. It is important to know what the actors who are a part of shaping MPs policy in Oregon would see as barriers and opportunities to doing so. We conducted …


Water Quality Analysis Of Ecoroof Runoff In Portland, Pranoti P. Deshmukh Aug 2019

Water Quality Analysis Of Ecoroof Runoff In Portland, Pranoti P. Deshmukh

Civil and Environmental Engineering Master's Project Reports

Portland, Oregon is internationally recognized for its implementation of sustainable stormwater management technologies. Ecoroof is one of the sustainable solutions to reduce stormwater runoff which also provides multiple environmental benefits. However, very little is known about the impact of ecoroofs on water quality of roof runoff. Stormwater runoff carries a significant amount of pollutants, which, if it directly enters a stream or river, degrades water quality and severely harms aquatic life.

This study evaluates the trends in the long-term water quality data from ecoroofs and conventional roofs in the Portland area. Mann Kendall trend test was used to detect the …


Long-Term Variation Of Summer Phytoplankton Communities In An Urban Lake In Relation To Lake Management And Climate Conditions, Yuan Xiao Grund Dec 2018

Long-Term Variation Of Summer Phytoplankton Communities In An Urban Lake In Relation To Lake Management And Climate Conditions, Yuan Xiao Grund

Dissertations and Theses

Eutrophication is one of the primary factors causing harmful cyanobacteria blooms in freshwater lakes; climate change such as warmer temperature can potentially further increase both frequency and intensity of blooms. This study investigated the long-term changes in water quality and summer phytoplankton assemblages in Oswego Lake, OR, in relation to lake management practices (e.g., hypolimnetic aeration and alum treatments), as well as climatic and regional meteorological conditions. Both water quality and phytoplankton assemblages were sampled biweekly during summer seasons between 2001 and 2013. The concentrations of total phosphorus (TP), soluble reactive phosphorus (SRP) and total nitrogen (TN) decreased 66%, 93% …


Using Wetlands To Prevent The Surface Accumulation Of Aphanizomenon Flos-Aquae From Upper Klamath Lake, Arick Christopher Rouhe Aug 2018

Using Wetlands To Prevent The Surface Accumulation Of Aphanizomenon Flos-Aquae From Upper Klamath Lake, Arick Christopher Rouhe

Dissertations and Theses

The ability to regulate buoyancy (sinking and floating) using cellular gas vesicles is a unique characteristic that allows many common bloom-forming cyanobacteria to accumulate at water surfaces and dominate systems. Typical control and management strategies include nutrient manipulation and phosphorus reduction, which are effective but do not reduce the advantage of buoyancy control. Since buoyancy control is based upon a mechanism that is driven by photosynthesis along with environmental conditions that trigger vesicle formation and ion exchange, buoyancy regulation can be influenced by manipulating extracellular conditions. In this study I manipulated extracellular conditions using wetland water and additions of potassium, …


Mapping Water Availability, Cost And Projected Consumptive Use In The Eastern United States With Comparisons To The West, Vincent C. Tidwell, Barbie D. Moreland, Calvin R. Shaneyfelt, Peter Kobos Jan 2018

Mapping Water Availability, Cost And Projected Consumptive Use In The Eastern United States With Comparisons To The West, Vincent C. Tidwell, Barbie D. Moreland, Calvin R. Shaneyfelt, Peter Kobos

Environmental Science and Management Faculty Publications and Presentations

The availability of freshwater supplies to meet future demand is a growing concern. Water availability metrics are needed to inform future water development decisions. Furthermore, with the help of water managers, water availability was mapped for over 1300 watersheds throughout the 31-contiguous states in the eastern U.S. complimenting a prior study of the west. The compiled set of water availability data is unique in that it considers multiple sources of water (fresh surface and groundwater, wastewater and brackish groundwater); accommodates institutional controls placed on water use; is accompanied by cost estimates to access, treat and convey each unique source of …


Effects Of Water Level Increase On Phytoplankton Assemblages In A Drinking Water Reservoir, Yangdong Pan, Shijun Guo, Yuying Li, Wei Yin, Pengcheng Qi, Jainwei Shi, Lanqun Hu, Bing Li, Shengge Bi, Jingya Zhu Jan 2018

Effects Of Water Level Increase On Phytoplankton Assemblages In A Drinking Water Reservoir, Yangdong Pan, Shijun Guo, Yuying Li, Wei Yin, Pengcheng Qi, Jainwei Shi, Lanqun Hu, Bing Li, Shengge Bi, Jingya Zhu

Environmental Science and Management Faculty Publications and Presentations

Excessive water level fluctuation may affect physico-chemical characteristics, and consequently ecosystem function, in lakes and reservoirs. In this study, we assessed the changes of phytoplankton assemblages in response to water level increase in Danjiangkou Reservoir, one of the largest drinking water reservoirs in Asia. The water level increased from a low of 137 m to 161 m in 2014 as a part of the South–North Water Diversion Project. Phytoplankton assemblages were sampled four times per year before, during and after the water level increase, at 10 sites. Environmental variables such as total nitrogen as well as phytoplankton biomass decreased after …


Hydrological Patterns And The Effects Of Land Use On Tss Concentrations And Yields In The Mccarthy Creek Watershed, Portland, Oregon, David Farmer Oct 2017

Hydrological Patterns And The Effects Of Land Use On Tss Concentrations And Yields In The Mccarthy Creek Watershed, Portland, Oregon, David Farmer

Environmental Science and Management Professional Master's Project Reports

The spread of impervious surface areas and the reduction of tree canopy via urbanization has numerous water quality impacts on Pacific Northwest watersheds. One such impact is elevated levels of Total Suspended Solids (TSS) in run-off during storm events, particularly in steep, forested watersheds undergoing urbanization. This project was developed in collaboration with the West Multnomah Soil and Water Conservation District and focused on the McCarthy Creek Watershed, as a case-study watershed located in Portland, OR. The study aimed to identify elevated TSS concentrations and yields during storm events on both mainstem and tributary sampling locations, establish the relationship between …


Temporal Variations Of Citizens’ Demands On Flood Damage Mitigation, Streamflow Quantity And Quality In The Korean Urban Watershed, Change-Yu Hong, Eun-Sung Chung Apr 2016

Temporal Variations Of Citizens’ Demands On Flood Damage Mitigation, Streamflow Quantity And Quality In The Korean Urban Watershed, Change-Yu Hong, Eun-Sung Chung

Urban Studies and Planning Faculty Publications and Presentations

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 …


Construction Of An Environmental Quality Index For Public Health Research, Lynne C. Messer, Jyotsna S. Jagai, Kristen M. Rappazzo, Danelle T. Lobdell May 2014

Construction Of An Environmental Quality Index For Public Health Research, Lynne C. Messer, Jyotsna S. Jagai, Kristen M. Rappazzo, Danelle T. Lobdell

Community Health Faculty Publications and Presentations

Background

A more comprehensive estimate of environmental quality would improve our understanding of the relationship between environmental conditions and human health. An environmental quality index (EQI) for all counties in the U.S. was developed.

Methods

The EQI was developed in four parts: domain identification; data source acquisition; variable construction; and data reduction. Five environmental domains (air, water, land, built and sociodemographic) were recognized. Within each domain, data sources were identified; each was temporally (years 2000–2005) and geographically (county) restricted. Variables were constructed for each domain and assessed for missingness, collinearity, and normality. Domain-specific data reduction was accomplished using principal components …


Getting Salmon Back In Salmon Creek: Systematizing Comparative Water Quality Analysis For Targeted Restoration, Zbigniew J. Grabowski, Sarah Janjua, Michael Swamer, Heejun Chang, Eric Watson Oct 2013

Getting Salmon Back In Salmon Creek: Systematizing Comparative Water Quality Analysis For Targeted Restoration, Zbigniew J. Grabowski, Sarah Janjua, Michael Swamer, Heejun Chang, Eric Watson

Geography Faculty Publications and Presentations

This presentation focuses on water quality restoration efforts in Salmon Creek


Water Supply, Demand, And Quality Indicators For Assessing The Spatial Distribution Of Water Resource Vulnerability In The Columbia River Basin, Heejun Chang, Il-Won Jung, Angela L. Strecker, Daniel Wise, Martin Lafrenz, Vivek Shandas, Hamid Moradkhani, J. Alan Yeakley, Yangdong Pan, Robert Allen Bean, Gunnar Johnson, Mike Psaris Mar 2013

Water Supply, Demand, And Quality Indicators For Assessing The Spatial Distribution Of Water Resource Vulnerability In The Columbia River Basin, Heejun Chang, Il-Won Jung, Angela L. Strecker, Daniel Wise, Martin Lafrenz, Vivek Shandas, Hamid Moradkhani, J. Alan Yeakley, Yangdong Pan, Robert Allen Bean, Gunnar Johnson, Mike Psaris

Geography Faculty Publications and Presentations

We investigated water resource vulnerability in the US portion of the Columbia River basin (CRB) using multiple indicators representing water supply, water demand, and water quality. Based on the US county scale, spatial analysis was conducted using various biophysical and socio-economic indicators that control water vulnerability. Water supply vulnerability and water demand vulnerability exhibited a similar spatial clustering of hotspots in areas where agricultural lands and variability of precipitation were high but dam storage capacity was low. The hotspots of water quality vulnerability were clustered around the main stem of the Columbia River where major population and agricultural centres are …


"Ecosystems", William E. Cooper Jun 1978

"Ecosystems", William E. Cooper

Special Collections: Oregon Public Speakers

From a lecture series with M.A. Arbib, "Environmental simulation and long-term planning."