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Full-Text Articles in Environmental Monitoring
Nutrients Mediate The Effects Of Temperature On Methylmercury Concentrations In Freshwater Zooplankton, Meredith P. Jordan, A. Robin Stewart, Collin A. Eagles-Smith, Angela L. Strecker
Nutrients Mediate The Effects Of Temperature On Methylmercury Concentrations In Freshwater Zooplankton, Meredith P. Jordan, A. Robin Stewart, Collin A. Eagles-Smith, Angela L. Strecker
Environmental Science and Management Faculty Publications and Presentations
Methylmercury (MeHg) bioaccumulation in freshwater aquatic systems is impacted by anthropogenic stressors, including climate change and nutrient enrichment. The goal of this study was to determine how warmer water temperatures and excess nutrients would alter zooplankton communities and phytoplankton concentrations, and whether those changes would in turn increase or decrease MeHg concentrations in freshwater zooplankton. To test this, we employed a 2 × 2 factorialexperimental design with nutrient and temperature treatments. Mesocosms were filled with ambient water and plankton from Cottage Grove Reservoir, Oregon, U.S.A., a waterbody that has experienced decades of elevated MeHg concentrations and …
Fish Species Introductions Provide Novel Insights Into The Patterns And Drivers Of Phylogenetic Structure In Freshwaters, Angela L. Strecker, Julian D. Olden
Fish Species Introductions Provide Novel Insights Into The Patterns And Drivers Of Phylogenetic Structure In Freshwaters, Angela L. Strecker, Julian D. Olden
Environmental Science and Management Faculty Publications and Presentations
Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) …
Sediment Nutrient Accumulation And Nutrient Availability In Two Tidal Freshwater Marshes Along The Mattaponi River, Virginia, Usa, Jennifer L. Morse, J. Patrick Megonigal, Mark R. Walbridge
Sediment Nutrient Accumulation And Nutrient Availability In Two Tidal Freshwater Marshes Along The Mattaponi River, Virginia, Usa, Jennifer L. Morse, J. Patrick Megonigal, Mark R. Walbridge
Environmental Science and Management Faculty Publications and Presentations
Sediment deposition is the main mechanism of nutrient delivery to tidal freshwater marshes (TFMs). We quantified sediment nutrient accumulation in TFMs upstream and downstream of a proposed water withdrawal project on the Mattaponi River, Virginia. Our goal was to assess nutrient availability by comparing relative rates of carbon (C), nitrogen (N), and phosphorus (P) accumulated in sediments with the C, N, and P stoichiometries of surface soils and above ground plant tissues. Surface soil nutrient contents (0.60–0.92% N and 0.09–0.13% P) were low but within reported ranges for TFMs in the eastern US. In both marshes, soil nutrient pools and …