EnviroAtlas - Average annual soil loss and sediment yield to waterbodies by 12-digit HUC for the Conterminous United States

This EnviroAtlas national dataset shows the average annual soil loss and sediment yield to waterbodies by 12-digit HUC subwatershed for the conterminous United States for 2011 with existing land use / land cover and under a scenario in which natural vegetation is removed. It also includes the soil loss and sediment yield prevented by natural vegetation, calculated as the difference between soil loss or sediment yield with existing land cover and under the vegetation removal scenario. This dataset is based on a collection of six rasters showing runoff, sediment delivery ratio, and sediment yield to streams and waterbodies under two land cover scenarios. The two scenarios are the existing vegetation scenario based on the 2011 National Land Cover Database (NLCD), and a scenario in which natural land cover was replaced with barren land. Average annual soil loss due to sheet and rill erosion was calculated using the Revised Universal Soil Loss Equation (RUSLE) equation for both scenarios. A Sediment Delivery Ratio (SDR) was then applied to both scenarios. The SDR was multiplied by the average annual soil loss to estimate net sediment yield to downstream waterways under both scenarios. These datasets can be used together to quantify the soil retention services of natural vegetation. The datasets used as inputs include the 2011 NLCD, 1971-2000 Rainfall-runoff erosivity factor from PRISM (Parameter-elevation Regressions on Independent Slopes Model), the U.S. Geological Survey's 30-meter digital elevation model (DEM), Soil Survey Geographic Database (SSURGO), and State Soil Geographic Database (STATSGO2) data, MODIS (Moderate Resolution Imaging Spectroradiometer) Normalized Difference Vegetation Index (NDVI), and the US Department of Agriculture (USDA)'s crop management zones (CMZs). This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).