Erosion predictions with the wind erosion equation (WEQ) using different climatic factors

Little information is available on the performance of the Wind Erosion Equation (WEQ) for estimating wind erosion under differing climatic conditions. The objective of this study was to assess the fitting of measured and WEQ-estimated wind erosion with different climatic C factors. Results showed that WEQ underestimated the annual wind erosion by 45 per cent when loaded with the historic C, obtained with climatic data records between 1981 and 1990. The monthly averaged C factor (monthly C, n = 12) underestimated the erosion by 29 per cent, the C factors of each one of the six studied years (annual C, n = 6) underestimated the erosion by 19 per cent, and the C factors of each one of the evaluated months (monthly C, n = 72) overestimated the erosion by 31 per cent. Precipitation explained most of C factors variability. C factors corresponding to high precipitation periods predicted low erosion amounts in no-till (NT) and conventional tillage (CT). C factors corresponding to low precipitation periods calculated high erosion rates in CT (143 t ha(-1) y(-1)) and low in NT (2.4 t ha(-1) y(-1)). The historical C factor predicted no erosion in NT and 7.1 t ha(-1) y(-1) in CT. These results indicated that the WEQ should be used with variable C factors in order to assess different climatic scenarios of the semiarid Argentina. Copyright (c) 2007 John Wiley & Sons, Ltd.