LAND COVER MAPPING FOR THE NEBRASKA COOPERATIVE HYDROLOGY STUDY IN THE CENTRAL PLATTE RIVER BASIN (COHYST)

Agriculture dominates the landscape of the Central Platte River Basin. Habitat loss has caused concern for the welfare of the millions of migratory birds that stop along the Platte on their way to northern breeding grounds. In response to the Platte River Cooperative Agreement between Nebraska, Colorado, and Wyoming, the Cooperative Hydrology Study in the Central Platte River Basin (COHYST) was established to develop hydrologic modeling and detailed studies in the Platte River Basin upstream of Columbus, NE. As part of the COHYST project, remote sensing, spatial, and field data have been incorporated to produce an accurate map of agricultural crops and other land cover in the Central Platte River Basin in 1997. Multi-date Landsat Thematic Mapper imagery was used to capitalize on the seasonal dynamics of the agricultural crops and native plant communities. Extensive crop and field data were used in collecting training sites used in the supervised classification. Distinctions were made between irrigated and non-irrigated crops using field and ancillary data.

Comprehensive and current information on land cover and land use (especially irrigation and crop patterns) are critical to COHYST, since hydrologic conditions change in relation to crop dynamics. Future COHYST modeling efforts will require examination of historical and current agricultural land cover patterns. Current mapping efforts using 1982 and 2001 satellite imagery will also be discussed. More information about the project can be found at http://www.calmit.unl.edu/cohyst/.