植被对含碎石土壤坡面降雨入渗和径流侵蚀的影响

目的]研究植被对含碎石土壤坡面入渗和径流侵蚀的影响,为合理配置三峡地区含碎石土壤坡面植被提供科学依据。方法]在建立的径流小区内铺设含碎石土壤,并配置不同种类、不同覆盖度的植被,进行人工降雨试验。结果]各类小区径流量排序为:裸坡灌木坡面草本坡面草灌混合坡面,入渗量与径流量排序相反,有植被覆盖坡面的壤中流大于裸坡;入渗率服从对数函数规律,产流强度呈幂函数变化;草地对水沙的调控机制更多的是直接拦沙;累计径流量和累计侵蚀量的关系均满足幂函数形式。结论]植被措施可有效地减少含碎石土壤坡面的水土流失,不同的植被措施减少的效益不同。

Effect of Vegetation on Rainfall Infiltration and Runoff Erosion and Sediment Yield in Gravel Soil Slope

Objective] Studying the influences of vegetation on rainfall infiltration and runoff erosion and sediment yield in order to provide a scientific basis for rationally allocating the vegetation in gravel soil slope in the Three Gorges area.Methods] Runoff plots containing gravel soil were set with different types and coverage of vegetation. Artificial rainfall experiments were conducted.Results] The amount of runoff showed as follows bare slope > shrub slope > herb slope > grass shrub mixed slope, in contrast, infiltration and runoff showed the opposite trend. The interflow in vegetation-covered slope was greater than that in the bare slope. Infiltration rate obeyed the law of logarithmic function, while the runoff yield strength varied as power function. The regulation mechanism of grassland to water and sediment was mostly direct sad blocking. The relationship between cumulative runoff and cumulative sediment yield showed as the power function.Conclusions] Vegetation measures can effectively reduce soil and water loss in gravel soil slope, and different vegetation measures represent the different reducing benefits.