DEVELOP AND IMPROVE STRATEGIES FOR MANAGEMENT OF IRRIGATED AGRICULTURAL CROPS AND SOILS
Location: Northwest Irrigation and Soils Research
Title: The importance and challenge of modeling irrigation-induced erosion
Submitted to: Journal of Soil and Water Conservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 12, 2007
Publication Date: June 18, 2007
Citation: Sojka, R.E., Bjorneberg, D.L., Trout, T.J., Strelkoff, T., Nearing, M.A. 2007. The importance and challenge of modeling irrigation-induced erosion. Journal of Soil and Water Conservation. 62(3):153-162.
Interpretive Summary: Irrigation- and rain-induced erosion result from similar physical and chemical processes, but very different systematics; thus, both cannot be predicted well using the same models. Modeling requirements for prediction of surface irrigation-induced erosion differ most from rainfed models. Poor predictive capability for surface irrigation erosion is especially problematic since surface irrigation accounts for 90% of world irrigation and 80% of US fruit and vegetable production. Globally, irrigation averages twice the yield and three times the profit of rainfed agriculture. Irrigation also plays a vital role in atmospheric cooling and C sequestration. The importance of developing a robust, reliable, accurate, transient state erosion model for all forms of irrigation can hardly be over-stated. Regional and national assessments of erosion and water quality impairment from irrigation runoff have been hampered for decades by the lack of appropriate models. This hinders management choices, resource conservation strategies and policy, as well as conservation practice compensation. Our paper details the aspects unique to irrigation that must be accounted for in models, and summarizes the progress toward irrigation-induced erosion model development.
Irrigation-induced erosion and rain-induced erosion result from very different systematics. Therefore, both cannot be predicted effectively using the same models. The average 2 fold yield and 3 fold economic advantage of irrigation over rainfed agriculture, coupled with the fragility of irrigated land and the strategic importance of irrigation development to meet world agricultural production needs, has raised the urgency for the development of robust, accurate, and precise irrigation-induced erosion models. Our paper details the rationale for separate irrigation-induced erosion models, presents essential aspects unique to irrigation that must be accounted for in the models, and summarizes the progress (to date) towards the goal of irrigation-induced erosion model development.