Submitted to: Catena
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/2/2005
Publication Date: 3/3/2005
Citation: Oneal, M.R., Nearing, M.A., Vining, R.C., Southworth, J., Pfeifer, R.A. 2005. Climate change impacts on soil erosion in Midwest United States with changes in crop management. Catena. 61(2005)166-184. Interpretive Summary: In this study we looked at the future of erosion and runoff in the Midwest U.S. under a changing climate, assuming that farmers would also be changing their practices to react to climate change. The climate has been changing in the U.S., in terms of precipitation becoming more intense and air temperature increasing, as part of a general global warming. Erosion should also change as precipitation and temperature change. For this research, we used an erosion model to predict what erosion and runoff would be with climate change in the states of Illinois, Indiana, Michigan, Ohio, and Wisconsin, in the years 2040-59 and 2080-99, if farmers changed the types of crops that they grow and the time that they planted crops in order to respond to climate change. Compared to earlier studies that did not look at changing management, we found more widely variable soil loss estimates based on the specific crop management and the geographic location. Generally, there was a large increase in soil loss and runoff compared to today. A decrease in corn yields from summer temperature stress appeared to lead to increased erosion, since low yields mean less plant cover to protect the soil from erosion. It matters a great deal what crop type or crop rotation is planted, and when the crop is planted, to accurately estimate future soil erosion, and this study suggests that more work needs to be done in predicting future crop management. The impact of this research is to show that in order to model and predict future erosion, we need to model what farmers do in the future, not just what they do today, and also to show a potential increase in erosion for the Midwest U.S. region. Prediction of increased future erosion can help manage valuable cropland, suggest the need for soil conservation strategies, and prevent loss of the food resource that would occur through the menace of soil erosion.
Technical Abstract: This study investigates potential erosion changes in the Midwestern United States under climate change, including the adaptation of farm management to climate change. Previous studies of erosion under climate change have not taken into account farmer choices of crop rotation or planting date, which would likely change under global warming. 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 several regions of the study area, simulated soil loss and runoff increased over 40% in 2040-59 and 2080-99, relative to 1990-99. Compared to studies that did not take into account changes in management, soil loss changes were more widely variable, dependent on crop rotation, planting date, and geographic area. Decreasing cover from temperature-stressed corn yields and increased monthly precipitation were important determining factors. The impact of this research is to show that future farm management needs to be modeled to predict future erosion; prediction of increased future erosion can help manage valuable cropland, suggest the need for soil conservation strategies, and prevent loss of the food resource that would occur through soil erosion.