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Full-Text Articles in Environmental Sciences

Stream-Associated Amphibian Habitat Assessment In The Portland-Vancouver Metropolitan Region, Andrew Evans Dietrich Dec 2012

Stream-Associated Amphibian Habitat Assessment In The Portland-Vancouver Metropolitan Region, Andrew Evans Dietrich

Dissertations and Theses

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 …


Survey Of Aquatic Invasive Species In Selected Umpqua National Forest Lakes And Ponds, Mark D. Sytsma, Rich Miller Jan 2012

Survey Of Aquatic Invasive Species In Selected Umpqua National Forest Lakes And Ponds, Mark D. Sytsma, Rich Miller

Center for Lakes and Reservoirs Publications and Presentations

Eleven lakes and ponds within the Umpqua National Forest were surveyed for invasive aquatic macrophytes, snails, bivalves, and crayfish during the summer of 2011. Yellow floating heart (Nymphoides peltata), an invasive floating leaf macrophyte species, was detected in Willow Sump within the Little River drainage. European ear snails (Radix auricularia), an invasive species present in several Umpqua National Forest waterbodies, were detected in Beaver Pond within the Steamboat Creek drainage. One native crayfish species, the signal crayfish (Pacifastacus leniusculus), was observed in Crayfish Lake within the Brice Creek drainage. Diverse assemblages of native plant species were observed in the lakes …


Climate Change Effects And Water Vulnerability In The Molalla Pudding River Basin, Oregon, Usa, Susan Amelia Wherry Jan 2012

Climate Change Effects And Water Vulnerability In The Molalla Pudding River Basin, Oregon, Usa, Susan Amelia Wherry

Dissertations and Theses

Water management plans are typically developed using historical data records and historical return periods for extreme events, such as floods or droughts. Since these analyses of return periods typically assume a certain degree of stationarity (constant mean, standard deviation, distribution) in hydrologic variables, the potential future impacts of climate change are excluded. In developing water management plans, predicted changes to climate variables should be considered to evaluate the degree of non-stationarity that may exist in the future. In this way, regions most sensitive to climate change can be identified and managed appropriately. This study performed such a task by using …


Groundwater Surface Trends In The North Florence Dunal Aquifer, Oregon Coast, Usa, Sarah Rebecca Doliber Jan 2012

Groundwater Surface Trends In The North Florence Dunal Aquifer, Oregon Coast, Usa, Sarah Rebecca Doliber

Dissertations and Theses

The North Florence Dunal Aquifer is the only feasible source for drinking water for the coastal city of Florence, Oregon and Florence's Urban Growth Boundary. High infiltration rates and a shallow groundwater table leave the aquifer highly susceptible to contamination from septic tank effluent, storm runoff, chemical fertilizers and recreational ATV use throughout the dunes. Public interest in the quality and quantity of the aquifer water has been sparked since the City of Florence received a grant from the Environmental Protection Agency for a watershed protection and restoration project. Delineation of the shallow groundwater surface and its relationship to the …


Greenhouse Gas Fluxes In Southeastern U.S. Coastal Plain Wetlands Under Contrasting Land Uses, Jennifer L. Morse, Marcelo Ardón, Emily S. Bernhardt Jan 2012

Greenhouse Gas Fluxes In Southeastern U.S. Coastal Plain Wetlands Under Contrasting Land Uses, Jennifer L. Morse, Marcelo Ardón, Emily S. Bernhardt

Environmental Science and Management Faculty Publications and Presentations

Whether through sea level rise or wetland restoration, agricultural soils in coastal areas will be inundated at increasing rates, renewing connections to sensitive surface waters and raising critical questions about environmental trade-offs. Wetland restoration is often implemented in agricultural catchments to improve water quality through nutrient removal. Yet flooding of soils can also increase production of the greenhouse gases nitrous oxide and methane, representing a potential environmental trade-off. Our study aimed to quantify and compare greenhouse gas emissions from unmanaged and restored forested wetlands, as well as actively managed agricultural fields within the North Carolina coastal plain, USA. In sampling …