降水特征与农作处理对坡耕地水土流失的动态研究

Dynamic Study on Soil and Water Loss in Different Rainfall Pattern and Farming Measures

通过在云南红壤坡耕地上建造径流小区,研究了自然降雨情况下6种不同农作处理的水土流失特征。结果表明:横坡垄作能有效减缓强降雨对坡耕地的侵蚀,减少径流流失,但不能有效防治长降雨的持续冲刷;顺坡垄作对强降雨和长降雨的侵蚀都不能有效减少水土流失。烤烟的不同生长时期对水土流失的影响因素不同。烤烟生长前期,垄作方式是影响水土流失的主要因素;在烤烟生长进入成熟期后,各处理间的泥沙流失量差异都不显著,各处理的地表植被覆盖率都达到最大化,地表植被覆盖率成为影响水土流失的主要因素。

In Yunnan red soil slope field,soil and water loss characteristics was studied by six kinds of farming measures,through monitoring the amount which Soil eroded in rainfall-runoff process by natural rainfall-runoff plot experiments. The study shows that contour ridge planting could effectively prevent the soil erosion by heavy rainfall in slope field,but not by consistent rainfall. The runoff amount of vertical ridge planting was more than contour ridge planting in heavy and consistent rainfall courses. The influencing factors of soil erosion were changed with tobacco growing period. The main factor affecting soil erosion at the early growth stage was ridge planting way. There was no obvious difference between the silt losses of farming measures during maturity. The maximal vegetation cover among different farming measures was the main factor affecting soil erosion.