Index Catalog // ScholarsArchive@OSU

The Impacts of Multiple Stressors on Aquatic Invertebrate Communities in the Umatilla River

Creator:: Clark, Hannah
Abstract:: Rivers impacted by human activities often have multiple stressors present. The effects of multiple stressors on biological communities can often be difficult to predict, due to the potential for complex interactions between stressors and communities. This thesis explores the impacts of two stressors often associated with agricultural land use, increased...
Resource Type:: Masters Thesis
Full Text:: the Umatilla River in eastern Oregon. The main objective of this study was to investigate the

Deep soil nitrogen survey, Lower Umatilla Basin, Oregon

Creator:: del Nero, Zachary Augustus
Abstract:: Soils of 49 agricultural and 2 "native condition" sites in the Lower Umatilla Basin, Oregon were sampled for nitrate-nitrogen, ammonium-nitrogen, chloride, and pH beginning in Fall of 1992. Several sites were sampled in Spring and Fall 1993 in order to indicate movement or loss of residual soil nitrogen over time....
Resource Type:: Masters Thesis
Full Text:: authority of the Oregon Department of Environmental Quality (ODEQ). The Lower Umatilla Basin Groundwater

Trace metal concentrations in the signal crayfish, Pacifastacus leniusculus (Decapoda: Astacidae), and the stonefly Pteronarcys californica (Plecoptera: Pteronarcyidae) along a downstream gradient of the Umatilla River

Creator:: Snyder, Jennifer L.
Abstract:: Metals are a persistent form of freshwater pollution and have been shown to bioaccumulate in aquatic macroinvertebrates through direct contact with contaminated water, sediments, and through consumption of contaminated organisms. This research explored the longitudinal bioaccumulation patterns of 5 common trace metals (Cr, Cu, Zn, Cd, and Pb) in the...
Resource Type:: Masters Thesis
Full Text:: ). The Umatilla River, located in the northeastern region of Oregon, is a natural location to study

Farm level response to agricultural effluent control strategies : the case of the Willamette Valley

Creator:: Taylor, Michael L. (Michael Lester), 1960-
Abstract:: Changes in the structure of the U.S. agricultural industry since World War II have transformed it into a highly productive component of the domestic economy. But these changes have not occurred without indirect costs. For example, the reliance on agricultural chemicals has produced environmental effects causing growing concern. In addition,...
Resource Type:: Dissertation
Full Text:: , Oregon. 111-4 Surface water pollution from nonpoint sources in the Willamette River Basin. 68 11I-5

An evaluation of well-water nitrate exposure and related health risks in the Lower Umatilla Basin of Oregon

Creator:: Mitchell, Thomas J.
Abstract:: Excessive nitrates in drinking water pose a human health threat, especially to infants. Methemoglobinemia, or blue-baby syndrome, is a potentially fatal condition that inhibits the ability of red blood cells to bind and transport oxygen. Nitrates/nitrites have also been linked to such conditions as cancer, birth defects, and behavioral and...
Resource Type:: Masters Thesis
Full Text:: health risks in the Lower Umatilla Basin of Oregon AN ABSTRACT OF THE THESIS OF Thomas J. Mitchell for

An eleven year study of nitrate leaching in vegetable production with winter cover crops

Creator:: Feaga, Jeff
Abstract:: The Willamette Valley of Oregon has high rates of winter precipitation that cause leaching losses of residual fertilizer nitrogen (N) as nitrate (NO₃). Cover crops may have potential to mitigate N loss. Shallow groundwater was sampled for 11 years from plots planted in summer vegetables with and without winter cover...
Resource Type:: Masters Thesis

An economic evaluation of on-farm strategies for reduction of nitrate groundwater pollution : the case of irrigated production in the Columbia basin

Creator:: Johnson, Scott Lee
Abstract:: Technological advances in agricultural production over the past 40 years have contributed to the high standard of living enjoyed by many in the United States. Extensive use of chemicals to enhance yield and improve crop quality has played a major role in creating this highly productive U.S. agricultural system. Increased...
Resource Type:: Dissertation
Full Text:: Dynamic Programming Model . . 62 3.1 General Soil Map for Western Umatilla County, Oregon 90 3.2 General

Field measurements of nitrate leaching below Willamette Valley row and mint crops

Creator:: Oregon State University. Extension Service, Feaga, Jeff, and Selker, John S.
Abstract:: According to the United States Geological Survey, 9 percent of wells in the Willamette Valley exceed the EPA’s 10 ppm drinking water standard for nitrogen in the NO3– compound, or NO3–-N. A study of 281 domestic drinking water wells in Lane County showed that 22 percent of the wells exceeded...
Resource Type:: Technical Report
Full Text:: -ROM. Oregon Depart- ment of Environmental Quality, Groundwater Section, Water Quality Division

The evolution of agricultural resource use strategies in the Willamette Valley

Creator:: Blok, Jack H.
Abstract:: Agriculture in the Willamette Valley, Oregon, has undergone continual change since the annual migrations of American pioneer farmers began to arrive in the early 1840's. The comparisons of data from each of the agricultural censuses of Oregon counties taken since 1850 confirms that change has been continual. The data revealed...
Resource Type:: Dissertation

Economic evaluation of alternative agricultural resources conservation policies

Creator:: Ogishi, Aya
Abstract:: The agriculture production system in the post-war United States is characterized as highly specialized and increasingly dependent on off-farm inputs. Although the US has traditionally supported agriculture with numerous government commodity programs such as target prices, nonrecourse loans, and deficiency payments, agriculture today is perceived as one of the major...
Resource Type:: Masters Thesis
Full Text:: deficiency payments, agriculture today is perceived as one of the major sources of environmental degradation

ScholarsArchive@OSU

The Impacts of Multiple Stressors on Aquatic Invertebrate Communities in the Umatilla River

Deep soil nitrogen survey, Lower Umatilla Basin, Oregon

Trace metal concentrations in the signal crayfish, Pacifastacus leniusculus (Decapoda: Astacidae), and the stonefly Pteronarcys californica (Plecoptera: Pteronarcyidae) along a downstream gradient of the Umatilla River

Farm level response to agricultural effluent control strategies : the case of the Willamette Valley

An evaluation of well-water nitrate exposure and related health risks in the Lower Umatilla Basin of Oregon

An eleven year study of nitrate leaching in vegetable production with winter cover crops

An economic evaluation of on-farm strategies for reduction of nitrate groundwater pollution : the case of irrigated production in the Columbia basin

Field measurements of nitrate leaching below Willamette Valley row and mint crops

The evolution of agricultural resource use strategies in the Willamette Valley

Economic evaluation of alternative agricultural resources conservation policies

Limit your search

Academic Affiliation

Advisor

Commencement Year

Committee Member

Creator

Date

Decade

Degree Field

Degree Level

Degree Name

File Format

Language

License

Location

Non-Academic Affiliation

Peer Reviewed

Resource Type

Rights Statement

Subject

Search Constraints

Search Results

Limit your search