不同植被类型下坡面径流侵蚀产沙差异性

利用野外模拟降雨试验分析不同植被类型不同雨强下坡面降雨入渗产流和侵蚀产沙过程特征及径流侵蚀产沙差异性,阐明了不同植被类型对坡面降雨侵蚀产沙过程的调控机理及其差异。结果表明:荒地、草地和坡耕地坡面产流产沙过程线均较林地强烈,呈现出多峰多谷的特点;植被类型和雨强及二者的交互效应均对产沙有显著影响,植被类型的作用大于雨强,交互效应相对较弱;植被类型和雨强对径流有显著影响,植被类型的作用大于雨强,此时交互效应的影响并不显著。各种类型的产沙量均存在显著差异,除荒地和草地两者径流量无明显差别外,其他两者之间存在显著差异。林地具有蓄水减沙的水土保持功效,草地具有直接拦沙的水土保持功效,植被对有效控制水土流失至关重要。该项研究有助于更好地理解植被、降雨和侵蚀之间的相互关系。

Difference of Runoff-Erosion-Sediment Yield Under Different Vegetation Type

Though the field simulated rainfall experiments,the characteristics and regulation of,as well as the difference of runoff and erosion sediment among,the slope rainfall-induced processes of infiltration,runoff generation,erosion and sedimentation under vegetation types and rainfall intensity were analyzed,the mechanism and variance of vegetation types regulating on the runoff and sediment process were clarified.The results show that slope runoff generation and sedimentation processes under wasteland,grassland and slope farmland conditions were stronger than those under forest conditions and showed multiple peaks and valleys.The vegetation types,rainfall intensity and interaction effect on sediment were significant.The sequence of influence was vegetation types,rainfall intensity and interaction effect.The vegetation types and rainfall intensity effect on runoff were important,the vegetation type’s influence was more significant than rainfall intensity,and interaction effect was little.The difference of sediment was significant under vegetation types,and it was also similar to the difference of runoff except under wasteland and grassland.Forest’s soil and water conservation function was based on water storage and sediment reduction.Grassland’s soil and water conservation function was based on direct sediment interception,and vegetation played a very important role in soil erosion control.The information of this study can be useful for better understanding the relationships between vegetation,soil erosion and precipitation.