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本文测定了504mm×504mm土盒中扰动Hagerstown粉砂粘壤土的细沟间侵蚀和径流,试验持续降雨20min,雨强为92mm/h,坡度为5%~85%。稳定状态下的土壤流失量(径流中的土壤悬移质)随坡度的增加而增加,5%坡侵蚀率为3.34g/m~2·min,85%坡增到22.47g/m~2·min。随坡度的增加土壤溅蚀的变化为:坡面下部增加,坡面上部减小,侧面稍有增加。土壤溅蚀总量(坡顶+坡底)与净坡底溅蚀量(坡顶-坡底)也随坡度的增加而增加。85%坡净土壤溅蚀达3.5g/m~2·min,85%的坡面上99%的土壤溅蚀运动到坡底。15%~85%坡面的稳定径流率没有区别,其平均径流率为66.5mm/h。单位面积的冲蚀和溅蚀总量同坡度呈线性关系。比较了实测的冲蚀和溅蚀总量与WEPP模型的估算值,结果表明坡度大于30%时实测值要大于WEPP模型的预测值(85%时要大1倍)。
In this paper, the erosion and runoff between two gouges in Hagerstown silty clay in 504mm × 504mm soil were measured. The rainfall was 20min, the rainfall intensity was 92mm / h and the slope was 5% ~ 85%. Soil loss at steady state (soil suspended matter in runoff) increased with the increase of slope, erosion rate at 5% slope was 3.34g / m ~ 2 · min, and slope at 85% increased to 22.47g / m ~ 2 min. With the increase of slope, the change of soil erosion is as follows: the lower part of the slope increases, the upper part of the slope decreases, and the side increases slightly. The amount of total soil erosion (top of slope + bottom) and net bottom slope erosion (top of slope - bottom) also increased with the increase of slope. The net soil erosion of 85% of the slope was 3.5g / m ~ 2 · min, and 99% of the soil erosion on 85% of the slope moved to the bottom of the slope. There was no difference between the stable runoff rates of 15% ~ 85% on the slope, and the average runoff rate was 66.5mm / h. The total amount of erosion and sputter erosion per unit area is linear with slope. The measured Erosion and Erosion Total and the WEPP model are compared. The results show that the measured value is greater than the WEPP model when the slope is greater than 30% (1 times larger at 85%).