Sediment transport modeling by the SWAT model using two scenarios in the watershed of Beni Haroun dam in Algeria

摘要

It is widely accepted that soil erosion has become a serious problem in recent decades for dams in general. In particular, the Dam of Beni Haroun (Algeria) is confronted with this problem. The present paper aims at investigating all the parameters likely to have an impact on this phenomenon. For this, the Soil and Water Assessment Tool model is applied for the purpose of estimating the solid inputs that would arrive at the dam, using two different scenarios in order to determine the most appropriate data that allows having the best representation of the watershed. The simulated results are compared with the ones obtained with the first scenario, for which R-2 is between 0.032 and 0.9 and the NSE (Nash-Sutcliffe efficiency coefficient) is in the interval 0.1-0.88, for the calibration period. However, the value of R-2 is found between 0.028 and 0.4 and the NSE in an interval of 0.27-0.88 for the validation period. In addition, R-2 is between 0.5 and 0.7, and the NSE ranges from 0.51 to 0.94 for the calibration period, in the second scenario; however, R-2 is in the interval from 0.27 to 0.52, and the NSE from 0.63 to 0.91 for the validation period. The total soil erosion rate of the watershed turns out to be equal to 3944.835 tons/km(2)/year.