Nghiên cứu hiệu chỉnh hệ số cây trồng (C) trong dự báo xói mòn đất sử dụng cho vùng núi phía Bắc Việt Nam

Abstract

The results of calculating the Ch coefficient calculated from the monitoring plots with 39 experiments with the coefficient C looked up from the table of the International Society of Soil Science (ISSS) show that there is a large difference, the C coefficient from the table is higher than the C_h calculated from the erosion monitoring plots ranged from 1.32 to 20.0 times, on average 6.07 times. The crop coefficient, after being calibrated by using the C coefficient looked up from the table of the International Soil Science Association multiplied by the monthly rainfall distribution weight and coverage, should be adjusted according to the coefficient of technical measures. Calculation results show that, for the main crops, these coefficients ranged from 0.20 to 0.8. The results of using the universal land loss equation (USLE) to test show that the C coefficient correction method has better predictive results than using the C coefficient of ISSS. This is expressed in the value of the correlation coefficient R, the prediction results with the usual and corrected C coefficients of 0.69 and 0.8 and the RMSE's mean squared error using coefficients C from ISSS is 82.09, also use the adjusted C coefficient is 11.01.