Impact of Climate Change on Inland Northwest Soil Erosion Under Various Land Management Practices

Abstract:

Changes in climate are hypothesized to have a multitude of impacts on the agricultural productivity of the inland Northwest of the United States. Much of the agricultural land in the region is composed of winter wheat and is managed under various tilling practices. Soil erosion under these various tilling practices and climate could be detrimental to the agricultural economy of the region and food security. We explore the susceptibility of the agricultural land of the region to erosion impacts under future climate scenarios using a two-pronged approach using the Water Erosion Prediction Project (WEPP) model. First, we assess the sensitivity of soil erosion to changes in climate variables including precipitation, temperature and precipitation intensity. This sensitivity analysis is done across several geographic regions, different hill slopes, soil types and land management practices. Secondly, we use downscaled climate projections from 20 climate models for the mid-21^st century to develop probabilistic estimates of changes in soil erosion across the region. These projected changes are further contextualized using the sensitivity experiments. Finally, we examine whether changes in erosion due to climate change may be partially offset by changes in land management.