不同结皮条件对崩岗崩积体坡面侵蚀的影响

Effects of Soil Crust on the Erosion of Colluvial Deposits in Granite Benggang

通过人工模拟降雨试验,对3个雨强下(1.00,1.67,2.33mm/min)和3种处理(未结皮、5min结皮、10min结皮)的崩岗崩积体坡面的产流产沙及细沟的发育与形态特征进行研究,结果表明:结皮产生使崩积体坡面的产流时间提前,出现细沟的时间延迟,土壤侵蚀量及细沟侵蚀密度、侵蚀宽度、侵蚀深度减少,结皮的存在具有减缓土壤侵蚀的作用;但10min结皮的产流时间和出现细沟的时间均比5min结皮的提前,土壤侵蚀量及细沟侵蚀程度增加,说明结皮程度高的侵蚀效应大于结皮程度低的,结皮只在一定程度上起到抗侵蚀的效果。

The erosion characteristics of the colluvial deposits under different crusts（non-crust, 5 min curst, 10 min crust）and rainfall intensities（1.00,1.67,2.33 mm/min） were analyzed. The results indicated that： The slope with crust would delay runoff-yielding time, but the time of rill erosion occurrence was earlier, and the soil loss, rill density, rill width, rill depth all decreased, these showed that crust would reduce the soil erosion. The time of runoff-yielding and rill erosion occurrence in 10 min crust slope was earlier than that in 5 min crust slope, the sediment yield and rill erosion all increased in 10 min crust slope, this indicated that the crust to some extent retarded the soil erosion.