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This landcover raster was generated through a Random Forest predictive model developed in R using a combination of image-derived and ancillary variables, and field-derived training points grouped into 18 classes. Overall accuracy, generated internally through bootstrapping, was 75.5%. A series of post-modeling steps brought the final number of land cover classes to 28.
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Training points collected in the field between 2012 and 2013 were grouped into 18 classes: Forested Burn (66), Foothill Woodland Steppe Transition (73), Greasewood Flat (73), Greasewood Steppe (239), Greasewood Sage Steppe (277), Great Plains Badlands (166), Great Plains Riparian (255), Low Density Sage Steppe (776), Medium Density Sage Steppe (783), Mixed Grass Prairie (555), Mixed Grass Prairie Burned (278), Ponderosa Pine Woodland and Shrubland (512), Riparian Floodplain (223), Semi-Desert Grassland (103), Sparsely Vegetated Mixed Shrub (252), Silver Sage Flat (70) , Silver Sage Steppe (64), and Water (246). When insufficient field data were available for a class, we augmented it through photointerpretation of...
The National Climate Assessment summarizes the impacts of climate change on the United States, now and in the future. A team of more than 300 experts guided by a 60-member Federal Advisory Committee produced the report, which was extensively reviewed by the public and experts, including federal agencies and a panel of the National Academy of Sciences. The report can be explored interactively at http://nca2014.globalchange.gov.
This study investigates potential changes in erosion rates in the Midwestern United States under climate change, including the adaptation of crop management to climate change. Previous studies of erosion under climate change have not taken into account farmer choices of crop rotations or planting dates, which will adjust to compensate for climate change. In this study, changes in management were assigned based on previous studies of crop yield, optimal planting date, and most profitable rotations under climate change in the Midwestern United States. Those studies predicted future shifts from maize and wheat to soybeans based on price and yield advantages to soybeans. In the results of our simulations, for 10 of...
This paper presents results of a study to assess the impacts of climate change on Midwestern streams and the ability of alternative regulations to maintain critical stream conditions. The study focuses on two generic types of regulations, those that restrict withdrawals to a constant flowrate at all times and those that allow withdrawals to increase and decrease with streamflow. Trading of water withdrawal permits is also considered as an adjunt to both policies. The study uses a modeling technique based on the SWAT model, applied to data for a Midwestern river basin. Streamflow was assumed stressed by agricultural irrigation, which is most intense during times when natural streamflows are at their lowest even without...
Much time and money has been spent over the last 40 years in the U.S. by farmers, soil scientists, hydrologists, geomorphologists, engineers, and ecologists attempting to document how agricultural best management practices, natural vegetation in riparian corridors, and stream rehabilitation or bank stabilization reduces sediment yields and improves ecological conditions at watershed outlets. These issues are especially pertinent in the steep erodible landscape of the Driftless Area in southwest Wisconsin, where many miles of world-class spring-fed trout streams remain on state impaired waters lists from excessive sedimentation and degraded habitat even though this area was the birthplace of the conservation movement...
Nitrate N from artificially drained soils of the upper Midwest USA is finding its way to the Mississippi River and then to the Gulf of Mexico. There is some concern that this nitrate N is causing hypoxia in the Gulf of Mexico. The DRAINMOD-N model was used to evaluate the long-term effect of N application rate and drain spacing on corn (Zea mays L.) yield and nitrate N losses. Prior to evaluation, the model was calibrated and then validated against long-term field data from southwestern Minnesota. A 24-yr simulation showed that climate plays a major role in determining drainage, yield, and nitrate N losses from a moderately well-drained Normania clay loam (fine-loamy, mixed, mesic Aquic Hapludoll) soil under continuous...
This project is part of the USDA's Mississippi River Basin Initiative. We are providing the water quality monitoring to assess the impact of various best management practices aimed at reducing nutrient runoff from agricultural lands.
map background search result map search result map Charles M. Russell National Wildlife Refuge Spot Landcover Classification in Relation to Greater Sage Grouse Training Points Training Points Charles M. Russell National Wildlife Refuge Spot Landcover Classification in Relation to Greater Sage Grouse