Upper Klamath Lake (UKL) and Agency Lake in south-central Oregon are hypereutrophic due to phosphorus (P) loading from both geologic and agricultural sources in the watershed. Restoring historic lake-fringe wetlands to provide P sinks around the lakes has been accepted as a favorable means of reducing lake P levels and...
A study of phosphorus loading and water quality implications was conducted for
the Oregon coastal lakes. The study was based on existing data for lake total phosphorus
concentrations and for watershed land uses. A phosphorus mass-balance model was
developed to predict lake total phosphorus concentrations from estimated phosphorus
loading from...
The anthropogenic introduction of nutrients to water bodies has been shown to alter the structure and function of natural aquatic ecosystems, yet national EPA lake and reservoir nutrient criteria remain too broad for effective regional water quality management. This study uses a reference site approach to propose numeric nutrient criteria...
High intensity sampling was undertaken to characterize the temporal and spatial
variability of oxidized nitrogen (NO3-N + NO2-N), ammonia-nitrogen (NH3-N), total
dissolved phosphorus, total unfiltered phosphorus and orthophosphorus (PO4-P) from two
adjacent small streams in Western Oregon's Coast Range, Deer Creek (303 ha) and Flynn
Creek (203 ha). Deer Creek...
Two Oregon reservoirs contaminated by different mercury
sources were compared for mercury distribution in sediment and
bioaccumulation by fish. The average mercury concentration in
the sediment of Cottage Grove reservoir (0.67 ± 0.05 μg/g dry
wt) was higher than for Dorena Reservoir (0.12 ± 0.01 μg/g dry
wt). Sediment mercury...