不同下垫面每次降雨水土流失特征及影响因素分析

Studying the characters and factors of water and soil losses over different ground covers under one rainfall event

研究了不同下垫面每次降雨产流产沙特征及其与降雨、降雨前期条件的内在关系。结果表明,百喜草覆盖和敷盖处理的产流产沙均远小于对照处理,相对对照处理,减水率在95%以上,减沙率在99.9%以上。影响百喜草覆盖和敷盖处理产流、产沙的最主要因素为降雨量,其次为降雨历时。同时,在影响百喜草覆盖和敷盖处理产沙因素中,产流影响显得更密切,也更直接。而对于对照处理,影响产流、产沙的最主要因素为降雨量和降雨强度,而且降雨量主要影响产流,降雨强度则主要影响产沙。

Water and soil losses are very serious and not only damage the eco-environment, but also restrict the sustainable development of the economy and society. To prevent water and soil loss and develop soil and water conservation in practice, the characteristics of water and soil losses, the internal relationship between water and soil losses, precipitation, and the condition of anti-rainfall over different ground covers under one rainfall event were studied. The amount of runoff and sediment in plots of P. notatum coverage and P. notatum mulch were considerably less than those in the control （〉95.0% and 99.9% respectively）. The most important factor was rainfall amount and next was the duration. Runoff affected soil losses more tightly and directly, but for the control, the important factors for water and soil losses were rainfall amount and intensity. Furthermore, rainfall amount mainly affected runoff while intensity mainly affected soil loss.