3.2. Grass hedges action on overland flow
The overland flow in plots with soybean, winter wheat, alfalfa and no crops is presented in Table 3, Table 4, Table 5 and Table 6, respectively. Table 3 shows that the overland flow under the precipitation intensity of 14 mm h−1 was very limited, even in the very wet run. For this reason in the following experiments, the 14–22–36 mm h−1 intensities were substituted with 22–36–63 mm h−1. From Table 3, Table 4, Table 5 and Table 6, we find that the control plots had the highest overland flow, followed by plots protected with Arundinella and Pennisetum hedges, in that order, under all rainfall intensities and slope gradients. The reducing effect of grass hedges on overland flow ranged from 0% to 99% depending on rainfall intensity, slope gradient and grass hedges. The results of statistical analysis indicate that in most cases the differences between the overland flow in Pennisetum protected plots and the control are significant (P < 0.05), whereas the differences between the overland flow in Arundinella protected plots and the control are not always significant (P > 0.05).
3.2. Grass hedges action on overland flow
The overland flow in plots with soybean, winter wheat, alfalfa and no crops is presented in Table 3, Table 4, Table 5 and Table 6, respectively. Table 3 shows that the overland flow under the precipitation intensity of 14 mm h−1 was very limited, even in the very wet run. For this reason in the following experiments, the 14–22–36 mm h−1 intensities were substituted with 22–36–63 mm h−1. From Table 3, Table 4, Table 5 and Table 6, we find that the control plots had the highest overland flow, followed by plots protected with Arundinella and Pennisetum hedges, in that order, under all rainfall intensities and slope gradients. The reducing effect of grass hedges on overland flow ranged from 0% to 99% depending on rainfall intensity, slope gradient and grass hedges. The results of statistical analysis indicate that in most cases the differences between the overland flow in Pennisetum protected plots and the control are significant (P < 0.05), whereas the differences between the overland flow in Arundinella protected plots and the control are not always significant (P > 0.05).
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