Surface water quality is a growing concern in the Willamette River Basin and elsewhere. The region's growing population is dependent on the availability of clean water for drinking water, irrigation, wastewater dilution, and wildlife habitat. Watershed management to produce economic goods and environmental services requires an understanding of basic hydrologic...
This thesis focuses on the identification of ecohydrological processes in nested system of catchments in a tropical alpine (the wet Andean páramo) ecosystem. We accomplish this by conducting a water stable isotopic characterization of water sources, an evaluation of the mean transit time (MTT) of streams waters, and the investigation...
The effect of landuse change on the hydrologic, biogeochemical and ecological response of watersheds is a concern throughout the world. To help characterize the potential magnitude of such changes, and of the potential to remediate or avoid undesirable features, studies focused on the cumulative watershed effects of site level change...
This thesis explores the challenges of monitoring stream hydrology in a warmer and wetter climate in the Kenai Peninsula (KP) and Prince William Sound (PWS) region of Southcentral Alaska, located on the traditional territories of the Dena’ina, Ahtna, Alutiiq/Sugpiaq, and Eyak People. The physical and climatological extremes of this region...
Bedrock groundwater dynamics in headwater catchments are poorly understood and
poorly characterized. Direct hydrometric measurements have been limited due to the
logistical challenges associated with drilling through hard rock in steep, remote and
often roadless terrain. Here we develop and use an inexpensive, portable bedrock
drilling system to explore bedrock...
Energy use and greenhouse gas emissions are on the forefront of planning policy in the world today. In the U.S., the transportation sector accounts for 50 percent of greenhouse gas (GHG) emissions, the most of any single sector. State and local levels of government have been very proactive in the...
Forest harvesting and climate change induced shifts in precipitation characteristics (i.e., intensity, type) may affect how water is partitioned on the landscape, with more water potentially being lost to evaporation or groundwater, and less water being partitioned into the stream. Long-term, paired watershed data allows us to assess these possible...
In the last few decades, a lot of studies have been conducted to study about the quality of stormwater runoff from various sites and conditions. Highways, residential areas, and commercial sites are the focus of most of these studies while limited studies have done examination of stormwater from Maintenance and...
We present a systems modeling approach to the development of a place-based ecohydrological model. The conceptual model is calibrated to a variety of existing observations, taken in watershed 10 (WS10) at the HJ Andrews Experimental Forest (HJA) in Oregon, USA, a long term ecological research (LTER) site with a long...
Urban development causes changes in the hydrology, increasing stormwater runoff volumes, which often leads to flooding and ecosystem degradation. This is a common phenomenon in most urban Africa, due to lack of stormwater drainage infrastructures. Green Infrastructure (GI) has been shown to be an effective approach to lessen the effects...
This thesis investigates the effects of wave energy converters (WECs) on water waves through the analysis of extensive laboratory experiments, as well as subsequent numerical simulations. Data for the analysis was collected during the WEC-Array Experiments performed at the O.H. Hinsdale Wave Research Laboratory at Oregon State University, under co-operation...
Faidherbia albida is a widely used tree species in sub-Saharan Africa, promoted for use in parkland agroforestry systems based on reduced competition with crops during the rainy season from its reverse leafing phenology and positive effect on soil fertility. Increases in growth and yield have been reported for crops such...
A novel mode of shallow aquifer management could increase the volumetric potential and distribution of underground, freshwater storage: Shallow aquifer storage and recovery (SASR). In this mode, water is efficiently stored in basin fill aquifers with strong hydraulic connection to surface water. Regional numerical modeling can provide a linkage between...
Coastal landslides and erosion are major natural hazards resulting in unstable slopes, constituting immense challenges to modern infrastructure. Developing, maintaining, and performing risk assessments of infrastructure on, or close to, these hazards require a detailed understanding of the geophysical processes destabilizing the slope. These efforts start with the collection of...
In the Western United States where 50-70% of annual precipitation comes in the form of winter snowfall, water supplies may be particularly sensitive to a warming climate. We worked with a network of stakeholders in the Big Wood Basin, Idaho, to explore how climate change may affect water resources and...
Field studies in watershed hydrology continue to characterize and catalogue the enormous heterogeneity and complexity of rainfall runoff processes in more and more watersheds, in different hydroclimatic regimes, and at different scales. Nevertheless, the ability to generalize these findings to ungauged regions remains out of reach. In spite of their...
Dissolved organic matter (DOM) is a critical component of the carbon cycle linking terrestrial and aquatic ecosystems. Although many factors influence DOM fluxes and quality in rivers, controls on DOM compositions in catchments of the western U.S. are poorly understood. UV and fluorescent spectroscopy is a simpler, faster, and less...
Contemporary fire effects are raising concerns about the resistance and resilience of dry mixed-conifer forests to large wildfires. Fire refugia – unburned or low-severity patches within fire perimeters – are understudied components of post-fire mosaics that may be key drivers of forest recovery following high-severity fire. Little is known about...
Precision irrigation has made spatially explicit water management a reality. However, detailed knowledge about the spatially variable evapotranspiration is often unavailable. One example location where we can begin to understand the impact of spatial variability on evapotranspiration is at the field edge, which contains a sharp discontinuity in surface conditions....
Diking and channelizing in the Toppenish Creek basin, associated with irrigated agricultural development, has altered its natural ecosystem function and hydraulic processes. We seek to answer two research questions: if surface waters are diverted for aquifer recharge in the winter, will this water be available for ecosystem function in the...
A Geyser in a stormwater (SW) and combined sewer system (CSS) is an oscillatory and violent release of a mixture of air and water through vertical shafts. Violent geysers are highly destructive. In the case of combined sewer systems, many municipalities operate their systems at a fraction of their maximum...
The Wood River Basin lies upstream of Upper Klamath Lake, the main reservoir of the USBR Klamath Irrigation Project that provides irrigation water to 210,000 acres of downstream land. Water allocation became a contentious issue in 2001 when drought led to curtailment of irrigation deliveries to the Klamath Irrigation Project...
The Tumalo Project at Tumalo Reservoir in Central Oregon was proclaimed a failure almost as soon as it was completed. As the reservoir filled with water diverted from Tumalo creek in the spring of 1915, sinkholes developed in the reservoir floor and every last drop of captured water disappeared into...
The glaciated coastal mountain watersheds that drain into the Gulf of Alaska (GOA) provide a model laboratory to explore the challenges of hydrological modeling and study the impact of climate and glacier cover change on regional hydrology. The region is data-sparse and contains a complex assemblage of topography and land...
Coastal communities throughout the US West Coast and elsewhere are facing the daunting task of preparing for climate change impacts, particularly the hazards from increased flooding and erosion. With sea-level rise, changing storminess patterns, and possible changes to the frequency and severity of major El Niño events, communities are already...
Rising global temperatures are having lasting effects on mountain snow environments in the form of diminishing snowpacks, shorter accumulation seasons, and shifts in meltwater timing. Seasonal snowpack is a vital source of water for natural and human systems. In the forested mountain landscapes of the Pacific Northwest seasonal snowmelt feeds...
Climate Change in the Northwest: Implications for Our Landscapes, Waters, and Communities is a report aimed at assessing the state of knowledge about key climate impacts and consequences to various sectors and communities in the Northwest United States. This report draws on two recent state climate assessments in Washington in...
The purpose of this watershed assessment is to provide an inventory and characterization of
watershed conditions in the Wilson River watershed and to provide recommendations that
address the issues of water quality, fisheries and fish habitat, and watershed hydrology.
The purpose of this watershed assessment is to inventory and characterize watershed conditions of the Miami River watershed and to provide recommendations that address the issues of water quality, fisheries and fish habitat, and watershed hydrology. This assessment was conducted by reviewing and synthesizing existing data sets and some new...
Abstract Watershed-scale fate/transport modeling of contaminants is a tool that scientists and land managers can use to assess pesticide contamination to stream systems. The Catchment Modeling Framework (CMF) is a catchment-scale fate/transport modeling tool. It was developed to help scientists and land managers assess the effects of possible land-use decisions...
The dominant controls on flow generation in steep, forested hillslopes are poorly understood. This dissertation examined the dominant flow processes operating at the hillslope scale, using a combined macroscale measurement and model development and analysis framework. Irrigation experiments at two steep forested hillslopes were conducted to isolate individual hillslope flow...
The physical controls of snowmelt in the Pacific Northwest (PNW) are poorly
understood. While there have been numerous field and modeling investigations at the
plot and watershed scale, few studies have identified how the snow energy balance
(EB) components vary in importance both spatially and temporally. The identification
of how...
This report presents a nested gauging study of streamflow variability from three sub-catchments (150-200 ha in area) of the Burns Creek catchment (565 ha) in the Entiat Experimental Forest of central Washington State. We test and reject the hypothesis that headwater catchments of this size are composed of physically and...
Effective watershed restoration planning and prioritization is often very difficult because decision making typically involves a large number of alternatives evaluated on the basis of multiple and often conflicting technical, social, economic, and environmental objectives and criteria. In order to solve such complex decision making problems, multiobjective decision making (MODM)...
Rapid increasing of renewable energies and the knowledge about their environmental effects are very limited. As a result, the renewable energies (e.g. solar or wind energies) will play a vital role in the future because it is well accepted by environmental friendly industries. This dissertation presents the modeling, data analysis...
This study uses semi-structured interviews and an online survey to explore the structure, challenges and outcomes of a five-year National Science Foundation-funded water scarcity modelling project in the Willamette River Basin of Oregon, USA. The research team chose to facilitate broader impacts by engaging stakeholders from the study’s inception (e.g....
Non-starter lactic acid bacteria (NSLAB) are found at low levels in fresh raw milk and are important to the dairy industry because of their potential impact on the flavor and texture of yogurt, sour cream, and cheese. The purpose of this study was to evaluate three methods for the identification...
As the western United States continues to experience prolonged drought that is extending water deficits and threatening ecosystem resilience and socioeconomic systems, it will be vital to understand the relationship between water use and transport for proper water resource management. This is especially important to the agricultural areas of the...
Large river basins integrate the signal of water from atmospheres to oceans. Climate change is widely expected to alter streamflow and potentially disrupt water management systems. We tested the ecological resilience -- capacity of headwater ecosystems to sustain streamflow under climate change – and the engineering resilience – capacity of...
Over the last 150 years, Oregon white oak habitat in the Willamette Valley has been converted to support grass crops, orchards and vineyards, cities, and conifer forests, nearly extirpating it from the Willamette Valley. Yet Oregon white oak offers many ecosystem services to the Willamette Valley and its residents. Recent...
We characterize how regional watersheds function as simple, dynamic systems through a series of hysteresis loops using measurements from NASA's Gravity Recovery and Climate Experiment (GRACE) satellites. These loops illustrate the temporal relationship between runoff and terrestrial water storage in three regional-scale watersheds (> 150 000 km²) of the Columbia...
We characterize how regional watersheds function as simple, dynamic systems through a series of hysteresis loops. These loops illustrate the temporal relationship between runoff and terrestrial water storage using measurements from NASA's Gravity Recovery and Climate Experiment (GRACE) satellites in three regional-scale watersheds (>150 000 km² ) of the Columbia...
The identification of sources of point and nonpoint fecal pollution is difficult to determine. Understanding the sources of fecal organisms in quality limited waters could greatly enhance our ability to restore and protect the water quality and habitat of these systems. Antibiotic resistance patterns of fecal streptococci bacteria were analyzed...
Biodiversity has become an important focus of ecological and wildlife research.
However, the social aspects of biodiversity policy and regulations, specifically the public's
perspectives and values about biodiversity, have not been adequately considered. This study
examines the range of opinion about biodiversity of six groups that are potentially affected by...
Increasing rates of species imperilment and the loss of biological diversity in naturally functioning ecosystems can be directly linked to accelerated urban development and the conversion of natural habitats to satisfy the needs of man. In combating this loss of biodiversity, scientists and policy makers alike recognize the relevance of...
In the face of climate change droughts are predicted to become more persistent, further intensifying the need for accurately predicting the timing and magnitude of summer streamflow in rivers. In order to determine the sensitivity of a watershed to drought, there is a need to describe what these drought conditions...
Headwater streams represent the majority of the drainage area of a river network and provide many critical functions supporting aquatic and terrestrial ecosystem health. The riparian zones that surround these streams are transitional areas between terrestrial and stream ecosystems, which provide key habitat for aquatic and terrestrial organisms, especially during...
Rainfall interception is a primary control over the moisture input to a forested ecosystem through the partitioning of precipitation into throughfall, stemflow, and an evaporated component (i.e. the interception loss). Rainfall interception is a spatially and temporally varying process at multiple scales, but heterogeneity in interception processes are poorly understood...
The Middle Fork John Day Basin in Northeastern Oregon is prime habitat for spring Chinook salmon and Steelhead trout. In 2008, a major tributary supporting rearing habitat, Big Boulder Creek, was restored to its historic mid-valley channel along a 1 km stretch of stream 800 m upstream of the mouth....
Full Text:
, knowledge, and support. Also, thanks to my committee
members Sherri Johnson, Kelly Vaché, and Stanley
The WET-Temp (Watershed Evaluation Tool Temperature) model is designed to take advantage of spatially explicit datasets to predict stream temperature distribution. Datasets describing vegetation cover, stream network locations, elevation and stream discharge are utilized by WET-Temp to quantify geometric relationships between the sun, stream channel and riparian areas. These relationships...
Glaciers are effective reservoirs because they moderate variations in runoff and
supply reliable flow during drought periods. Thus, there needs to be a clear
understanding of the influence of glacier runoff at both the basin and catchment scale.
The objectives of this study were to quantify the late summer contributions...
Natural resource management and policy is ideally informed by the best available science. Natural resource researchers ideally participate in broader impacts activities to extend the reach of their best available research. However, there are many cultural, institutional, and practical barriers to participating in broader impact activities and to incorporating science...
The levels of cooperation in efforts towards transboundary water management in the Aral Sea basin have ranged from high to low over the past few decades, due in part to diverse purposes for water use in the region. Two important and often conflicting uses are agriculture and hydropower, which tend...
Peakflow frequency analysis is used in forest hydrology for designing stream crossing structures such as culverts and bridges. The traditional approach to frequency analysis is based on the assumption that the observed sample of peakflows represents a homogeneous population. It is not clear if using the "homogeneous" population of the...
Decision-making in environmental management is complex due to the multiplicity arid diversity of management objectives and technological choices. This suggests that modelers and experts could utilize (I) multiple-criteria decision-making (MCDM) approaches to assist stakeholder groups in integrating and synthesizing relevant data and information to address ecological and socio-economic concerns and...
Throughout many of the world’s mountain ranges snowpack accumulates during the winter and into the spring, providing a natural reservoir for water. As this reservoir melts, it fills streams and recharges groundwater for over 1 billion people globally. Despite its importance to water resources, our understanding of the storage capacity...
This annotated bibliography was prepared for the Salmon Anchor Habitat Work Group. This group was formed by the Oregon Department of Forestry to review and evaluate the Salmon Anchor Habitat Strategy as directed by the 2003 Oregon Legislature. The Salmon Anchor Habitat Strategy is a component of management plans developed...
Forest management is rapidly undergoing a transformation from a discipline based on efficient commodity production to one for multiple uses, especially on federally managed land in the United States. This new management paradigm has challenged silviculturists to develop and adapt forest management techniques that can deal with increased demands. Using...
Tillamook Bay is the second largest estuary on the Oregon coast, and concerns have been raised whether human induced impacts have been responsible for the perceived increase in sedimentation rates during the past century. Major land-use practices within the five watersheds of the Bay include logging, forest fires, the construction...
We have sufficient evidence that our historical management of natural resources is not sustainable. Food production is stagnating or declining. Nonrenewable energy sources on which the energy sector has historically depended are being rapidly depleted. Water resources, for which the energy and food sectors compete, are being depleted and impaired....
This study models poverty changes across the United States between 1990 and 2000 as a function of spatial poverty variables (variables that attempt to capture the spatial effects of poverty and poverty changes), social capital, local employment growth, and demographic controls. Newly available decennial census data at the tract level...
Wetland restoration mitigates effects of agricultural development on water quality, flooding, and habitat loss. Multi-objective optimization for wetland locations and sizes has not included objective functions for water quality, hydrology, and habitat in unison, limiting analysis of trade-offs among these ecosystem services. This study establishes two methods to improve the...
This work furthers the understanding of processes occurring in catchments that affect stream nitrate concentrations using two different approaches: a temporally intensive case study of three headwater catchments with varying land use (through storm event monitoring) and a spatially intensive study on the regional scale (through statistical modeling) of 1st-4th...
The specific objectives of this dissertation are to determine subsurface flow
behaviors across different antecedent wetness conditions from a top-down perspective
and to mechanistically assess the hydrological controls on DOC and N transport at the
hillslope and catchment scale. The study area is a small catchment where hillslopes
issue directly...
The development of ecohydrological frameworks and theories under the ongoing global climate crisis depends on the development of new and advanced ecohydrological measurements. Currently, numerous of datasets have been collected at plot and ecosystem levels to understand the complex interactions of along the soil, plant, and atmosphere continuum. The development...
Recommendations are provided in this watershed analysis to identify actions and management decisions on the part of BLM that might improve watershed health in the Trask River watershed.
Irrigated agriculture constitutes the greatest consumptive water use globally, so that irrigation efficiency measures are an important part of global efforts to best utilize this limited resource. However, greater irrigation efficiency must be achieved while simultaneously maintaining or increasing crop yields and farming profitability. Incremental water use decisions are made...
Numerous studies have explored how alluvial channel size and morphology are adjusted to different sediment and flow conditions, yet we still know very little about how and to what degree the flow regime controls channel form and processes. We use the term ‘channel form’ to refer to the size and...
In this watershed assessment, the authors of the report summarized current conditions and data gaps within the Necanicum River watershed to help to identify how current and past resource management is impacting aquatic resources.
A study is conducted to provide information useful to the future development of agro-pastoralists
in the Kolda Region through an economic and socio-cultural analysis of the
practice of stabling. Two main issues are addressed: the generation and distribution of
profits and the factors related to adoption of stabling. A partial...
Reinhabitation is an approach to building local cultures and economies within industrial society. The food system is a vital starting point. What are the principles of reinhabitory food systems? What are the possibilities for a locally adapted food system in the Marys River region of western Oregon? I describe past...
Consistent with its charge under Oregon House Bill 3543, the Oregon Climate Change Research Institute (OCCRI) conducts a biennial assessment of the state of climate change science, including biological, physical, and social science, as it relates to Oregon and the likely effects of climate change on Oregon. This fifth Oregon...
A first-order approximation is made of the frequency and magnitude of bedload transport downstream of the Pelton-Round Butte Dam Complex, lower Deschutes River, Oregon with implications for salmonid spawning habitat. Field measurements of channel hydraulics, geometry, and particle size were combined with one-dimensional hydraulic and bedload transport models to determine...