Spatial and temporal evaluation of water quality response to climate variability and land use change in South Dakota watersheds

Abstract:

Land use dynamics and climate change can have considerable effects on watershed hydrology and water quality. Recent research showed that 1 to 5% of grassland is being annually converted to cropland in the Western Corn Belt region, including South Dakota (SD). At the same time, the effects of climate on water resources have been a concern in the region. This study aims to assess the potential impacts of hitorical climate and land use change on water quality (sediment, nitrate, and total phosphorus losses) in two representative SD watersheds by using the Soil and Water Assessment Tool (SWAT) with historical climate and land use data. The specific objective of this study is to characterize water quality changes that possibly occurred in South Dakota between the years 1980s and 2000s based on SWAT model simulations. This study will provide an elaborated view of water quality characteristics in South Dakota watersheds to support further research and understanding of water quality impacts of future agricultural activities in the state.