Upper Washita River Experimental Watersheds: Land Cover Data Sets (1974-2007) for Two Southwestern Oklahoma Agricultural Watersheds

Land cover data sets were developed for 1997, 1999, 2003, 2005, 2006, and 2007 for the Little Washita River and Fort Cobb Reservoir experimental watersheds (LWREW and FCREW, respectively), located in southwestern Oklahoma, to support remote sensing based studies of soil water content. A previously unpublished retrospective land cover analysis covering the years 1974, 1981, 1985, 1989, and 1994 was conducted to complement these data sets to gain a sense of the dynamics of land cover in both the LWREW and FCREW over the 33 yr. Each of these studies used satellite-based sensors of various spatial, radiometric, and spectral resolutions, but the number of images used, image date, and methods used to analyze the images varied from study to study. Our purpose was to document the details of the retrospective land cover study, to compare land cover between watersheds with time, and to compare findings from the various studies to elucidate changes or trends in land cover in each watershed during the 33 yr the data sets represent. Information on how to access to the data sets is also given. The LWREW was a grassland watershed that changed little during the study period. The FCREW was divided between grassland and cropland, but the cropland portion exhibited dynamic behavior that appeared correlated with peanut (Arachis hypogaea L.) price supports and Conservation Reserve programs. Dynamic land use information coupled with information concerning conservation practices will enhance assessment of conservation practice effectiveness as well as improve modeling of the fate and transport of chemicals and nutrients in watersheds.