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We characterized seafloor sediment conditions near the mouth of the Elwha River from underwater photographs taken every four hours from September 2011 to December 2013. A digital camera was affixed to a tripod that was deployed in approximately 10 meters of water (Tripod location from September 2011 to April 2013: 48.15333, -123.55931; tripod location from April 2013 to December 2013: 48.15407, -123.55444). Each photograph was qualitatively characterized as one of six categories: (1) base, or no sediment; (2) low sediment; (3) medium sediment; (4) high sediment; (5) turbid; or (6) kelp. For base conditions, no sediment was present on the seafloor. Low sediment conditions were characterized by a light dusting of...
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In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring has been conducted on streams and rivers throughout the Nation. Outside of the NAWQA project, the USGS and other Federal, State, and local agencies also have collected long-term water-quality data to support their own assessments of changing water-quality conditions. Data from these multiple sources have been combined to support...
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This dataset depicts relative erosion rate derived for all land draining above the Mesoamerican reef. It is a function of slope, land cover type, precipitation and soil type. The indicators developed by the Reefs at Risk in the Caribbean project enable detailed comparative analyses of threats on many scales. The Reefs at Risk indicators are a simplification of human activities and complex natural processes. This data set was derived at the World Resources Institute for input to the sedimentation and pollution from watershed based sources threat analysis. Agriculture, though important to economic development and food security, is a source of increased sediment, nutrient, and pesticide runoff. Threats from sedimentation...
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Using basins derived from a hydrologically-corrected 30m resolution DEM as a unit for summary statistics, we provide a series of indicators focused on land-based sources of threat within the US Virgin Islands and Puerto Rico. This includes indicators of a) the relative vulnerability of the land to erosion (based on slope, precipitation and soil erodibility); b) the relative erosion potential (REP) of the land, based on the relative vulnerability of the land, coupled with the current land cover type; c) the sediment delivery rate for each basin (percentage of eroded which reaches the river mouth); d) estimated sediment delivery for the basin, given current land use;
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The State of Alaska's Strategic and Critical Minerals (SCM) Assessment project, a State-funded Capital Improvement Project (CIP), is designed to evaluate Alaska's statewide potential for SCM resources. The SCM Assessment is being implemented by the Alaska Division of Geological & Geophysical Surveys (DGGS), and involves obtaining new airborne-geophysical, geological, and geochemical data. For the geochemical part of the SCM Assessment, thousands of historical geochemical samples from DGGS, U.S. Geological Survey (USGS), and U.S. Bureau of Mines archives are being reanalyzed by DGGS using modern, quantitative, geochemical-analytical methods. The objective is to update the statewide geochemical database to more clearly...
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This metadata record documents 11 comma delimited tables representing the amount of reported best management practice (BMP) implementation for the years from 1985 to 2014 at three geographic scales: county or land-river modeling segment, River Input Monitoring (RIM) station drainage areas, and the entire Chesapeake Bay Watershed (CBWS). Data originated from the Chesapeake Bay Watershed jurisdictions including Maryland, Pennsylvania, Virginia, Delaware, New York, West Virginia, and the District of Columbia. Data were reported to the Chesapeake Bay Program for an annual review of progress toward meeting nitrogen, phosphorus, and sediment reduction goals.
map background search result map search result map Mesoamerican Relative Erosion Rate Puerto Rico Watershed Indicators by Basin Water-quality and streamflow datasets used in the Weighted Regressions on Time, Discharge, and Season (WRTDS) models to determine trends in the Nation’s rivers and streams, 1972-2012(output) Characterization of seafloor photographs near the mouth of the Elwha River during the first two years of dam removal (2011-2013) Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Tonsina area, Valdez Quadrangle, Alaska 1) Best management practice implementation in the Chesapeake Bay watershed from 1985 to 2014 Characterization of seafloor photographs near the mouth of the Elwha River during the first two years of dam removal (2011-2013) Geochemical reanalysis of historical U.S. Geological Survey sediment samples from the Tonsina area, Valdez Quadrangle, Alaska Puerto Rico Watershed Indicators by Basin 1) Best management practice implementation in the Chesapeake Bay watershed from 1985 to 2014 Mesoamerican Relative Erosion Rate Water-quality and streamflow datasets used in the Weighted Regressions on Time, Discharge, and Season (WRTDS) models to determine trends in the Nation’s rivers and streams, 1972-2012(output)