土壤结皮对降雨入渗和产流产沙的影响

Effects of soil encrustation on rainfall infiltration,runoff and sediment generation

依据250场次人工降雨和相应的径流、泥沙资料,采用对比法,分析结皮与无结皮土壤对降雨入渗和产流产沙的影响。结果表明,非结皮土壤的平均入渗率是结皮土壤的1.25倍,平均产沙总量为1.28倍,而结皮土壤的平均产流总量是非结皮土壤的1.15倍。因此,土壤结皮具有减缓降雨入渗、增大地表径流和抑制产沙的作用,且雨强愈小影响作用愈大,雨强愈大,影响作用愈小。

Effects of soil encrustation and non-encrustation on rainfall infiltrating, runoff and sediment yield were studied under condition of 250 simulated rainfalls indoor and data of runoff and sediment accordingly. By comparison analysis, results showed that average infiltration rate of non-encrustation soil was 1.5 times as much as that of encrustation soil, and average total amount of sediment generation was 1.28 times as much as that of encrustation soil, but average total amount of runoff generation of encrustation soil was 1.15 times as much as that of non-encrustation soil. Therefore, soil encrustation had a function of slowing down rainfall infiltration, increasing surface runoff and restraining sediment generation. The weaker rainfall intensity, the bigger the function is, and the reverse is also true.