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Full-Text Articles in Physical Sciences and Mathematics
Grassland Bird Use Of Conservation Reserve Program Fields In The Great Plains, Douglas H. Johnson
Grassland Bird Use Of Conservation Reserve Program Fields In The Great Plains, Douglas H. Johnson
Publications of the US Geological Survey
The area enrolled in the Conservation Reserve Program in the Great Plains is enormous: nearly 18 million acres, or more than 7 million hectares, in Montana, North Dakota, South Dakota, Wyoming, Nebraska, Colorado, Kansas, Oklahoma, and Texas. This change in land use has had a huge influence on grassland bird populations. Many, but certainly not all, grassland species flourish in CRP habitats. Responses to the program vary not only by species, but by region, year, vegetation composition in a field, and whether or not a field was hayed or grazed. Further, the large scale of CRP has allowed researchers to …
Mercury Bioaccumulation In Fish In A Region Affected By Historic Gold Mining: The South Yuba River, Deer Creek, And Bear River Watersheds, California, 1999, Jason T. May, Roger L. Hothem, Charles N. Alpers, Matthew A. Law
Mercury Bioaccumulation In Fish In A Region Affected By Historic Gold Mining: The South Yuba River, Deer Creek, And Bear River Watersheds, California, 1999, Jason T. May, Roger L. Hothem, Charles N. Alpers, Matthew A. Law
Publications of the US Geological Survey
Mercury that was used historically for gold recovery in mining areas of the Sierra Nevada continues to enter local and downstream water bodies, including the Sacramento–San Joaquin Delta and the San Francisco Bay of northern California. Methylmercury is of particular concern because it is the most prevalent form of mercury in fish and is a potent neurotoxin that bioaccumulates at successive trophic levels within food webs. In April 1999, the U.S. Geological Survey, in cooperation with several other agencies—the Forest Service (U.S. Department of Agriculture), the Bureau of Land Management, the U.S. Environmental Protection Agency, the California State Water Resources …
Metals Transport In The Sacramento River, California, 1996–1997 Volume 2: Interpretation Of Metal Loads, Charles N. Alpers, Ronald C. Antweiler, Howard E. Taylor, Peter D. Dileanis, Joseph L. Domagalski
Metals Transport In The Sacramento River, California, 1996–1997 Volume 2: Interpretation Of Metal Loads, Charles N. Alpers, Ronald C. Antweiler, Howard E. Taylor, Peter D. Dileanis, Joseph L. Domagalski
Publications of the US Geological Survey
Metals transport in the Sacramento River, northern California, from July 1996 to June 1997 was evaluated in terms of metal loads from sam-ples of water and suspended colloids that were collected on up to six occasions at 13 sites in the Sacramento River Basin. Four of the sampling periods (July, September, and November 1996; and May–June 1997) took place during relatively low-flow conditions and two sampling periods (December 1996 and January 1997) took place during high-flow and flooding conditions, respec-tively. This study focused primarily on loads of cadmium, copper, lead, and zinc, with secondary emphasis on loads of aluminum, iron, …
Mercury Contamination From Historic Gold Mining In California, Charles N. Alpers, Michael P. Hunerlach
Mercury Contamination From Historic Gold Mining In California, Charles N. Alpers, Michael P. Hunerlach
Publications of the US Geological Survey
Mercury contamination from historic gold mines represents a potential risk to human health and the environment. This fact sheet provides background information on the use of mercury in historic gold mining and processing operations in California, and describes a new USGS project that addresses the potential risks associated with mercury from these sources, with emphasis on historic hydraulic mining areas. Miners used mercury (quicksilver) to recover gold throughout the western United States at both placer (alluvial) and hardrock (lode) mines. The vast majority of mercury lost to the environment in California was from placer-gold mines, which used hydraulic, drift, and …
Metals Transport In The Sacramento River, California, 1996–1997 Volume 1: Methods And Data, Charles N. Alpers, Howard E. Taylor, Joseph L. Domagalski
Metals Transport In The Sacramento River, California, 1996–1997 Volume 1: Methods And Data, Charles N. Alpers, Howard E. Taylor, Joseph L. Domagalski
Publications of the US Geological Survey
Metals transport in the Sacramento River, northern California, was evaluated on the basis of samples of water, suspended colloids, streambed sediment, and caddisfly larvae that were collected on one to six occasions at 19 sites in the Sacramento River Basin from July 1996 to June 1997. Four of the sampling periods (July, September, and November 1996; and May–June 1997) took place during relatively low-flow conditions and two sampling periods (December 1996 and January 1997) took place during high-flow and flooding conditions; respectively. Tangential-flow ultrafiltration with 10,000 nominal molecular weight limit, or daltons (0.005 micrometer equivalent), pore-size membranes was used to …
Land Cover Trends Dataset, 1973–2000, Christopher E. Soulard, William Acevedo, Roger F. Auch, Terry L. Sohl, Mark A. Drummond, Benjamin M. Sleeter, Daniel G. Sorenson, Steve Kambly, Tamara S. Wilson, Janis L. Taylor, Kristi L. Sayler, Michael P. Stier, Christopher A. Barnes, Steve C. Methven, Thomas R. Loveland, Rachel Headley, Mark S. Brooks
Land Cover Trends Dataset, 1973–2000, Christopher E. Soulard, William Acevedo, Roger F. Auch, Terry L. Sohl, Mark A. Drummond, Benjamin M. Sleeter, Daniel G. Sorenson, Steve Kambly, Tamara S. Wilson, Janis L. Taylor, Kristi L. Sayler, Michael P. Stier, Christopher A. Barnes, Steve C. Methven, Thomas R. Loveland, Rachel Headley, Mark S. Brooks
Publications of the US Geological Survey
The U.S. Geological Survey Land Cover Trends Project is releasing a 1973–2000 time-series land-use/land-cover dataset for the conterminous United States. The dataset contains 5 dates of land-use/land-cover data for 2,688 sample blocks randomly selected within 84 ecological regions. The nominal dates of the land-use/land-cover maps are 1973, 1980, 1986, 1992, and 2000. The land-use/land-cover maps were classified manually from Landsat Multispectral Scanner, Thematic Mapper, and Enhanced Thematic Mapper Plus imagery using a modified Anderson Level I classification scheme. The resulting land-use/land-cover data has a 60-meter resolution and the projection is set to Albers Equal-Area Conic, North American Datum of 1983. …
Water Quality In The Sacramento River Basin, California,1994–98, Joseph L. Domagalski, Donna L. Knifong, Peter D. Dileanis, Larry R. Brown, Jason T. May, Valerie Connor, Charles N. Alpers
Water Quality In The Sacramento River Basin, California,1994–98, Joseph L. Domagalski, Donna L. Knifong, Peter D. Dileanis, Larry R. Brown, Jason T. May, Valerie Connor, Charles N. Alpers
Publications of the US Geological Survey
This report summarizes major findings about water quality in the Sacramento River Basin that emerged from an assessment conducted between 1994 and 1998 by the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program. Water quality is discussed in terms of local and regional issues and compared to conditions found in all 36 NAWQA study areas, called Study Units, assessed to date. Findings are also explained in the context of selected national benchmarks, such as those for drinking-water quality and the protection of aquatic organisms. The NAWQA Program was not intended to assess the quality of the Nation's drinking water, …