金沙江不同林地坡面的产流产沙特征研究

Study on Runoff and Sediment Production in the Different Forest at Jinshajing River

为解决金沙江水土流失问题,在金沙江头塘小流域水源涵养林生态系统定位研究站内,选择典型人工林为研究对象,对4种典型生态恢复人工林类型(21年生云南松林、19年生旱冬瓜林、19年生银荆林和荒草地)的产流产沙特征进行研究。结果表明,4种林地坡面的产流量、产沙量和土壤侵蚀强度都表现出相同的大小规律,都为云南松林的最小,其次是银荆林和旱冬瓜林,荒草地的产流量、产沙量、土壤侵蚀强度都是最大的,分别为云南松林的3.05倍、6.23倍、6.29倍,说明云南松林的水土保持效果好。产流量、产沙量与降雨量都呈正相关关系,径流系数与产沙量呈正相关关系,即降雨在坡面产流时,径流系数增大,即产流量增大,产沙量也随之增大。由此可知,营造良好的人工林林分可以防止金沙江头塘小流域水土流失。

In order to solve problem of soil and water loss in Jinshajiang River,locate in the ecosystem research station of Jinshajiang River Basin,four typical ecological restoration plantations were selected as the research object,21-year-old of pure forest of Pinus yunnanensis,19-year-old of pure forest of Alnus nepalensis,19-year-old of pure forest of Acacia dealbata,and the waste-grassland,for the research on the characteristics of soil infiltration,runoff and sediment production,and the benefits of water conservation and ecological restoration.The results showed,four kinds of forest land in the runoff production,sediment production and soil erosion intensity of four kinds of forest lands exhibit the same order,which is:Pinus yunnanensis<Acacia dealbata<Alnus nepalensis<waste-grassland.The runoff production,sediment production and soil erosion intensity of waste-grassland is the biggest,its runoff production is 3.05 times of Pinus yunnanensis,its sediment production is 6.23 times of Pinus yunnanensis and its soil erosion intensity is 6.29 times of the smallest of Pinus yunnanensis.Description of the pure forest of Pinus yunnanensis has the most effective ecological benefit on soil and water conservation.There were positive correlation between both runoff yield,sediment yield with rainfall,there was positive correlation between runoff coefficient with sediment yield.Thus,when runoff coefficient donated large,runoff yeild increases namely,sediment yield will increases,too.So,good plantation could prevented soil and water loss in Jinshajiang River.