金沙江流域退耕还草地水土保持效益分析研究

Benefit of Forage on Water and Soil Conservation in Jinsha Valley

为评价牧草在防止水土流失上的作用,2001年在金沙江流域退耕还林还草综合配套技术试验示范区建立了径流观测场。3年的试验结果表明:林草复合模式能有效地控制水土流失,其植被覆盖能显著地降低径流速度而增加雨水入渗,减少径流和侵蚀量。退耕还草后,土壤养分流失减少,土壤体积质量(容重)降低,土壤理化性质改善,由于牧草能截获流失的养分,试验区具有更高的草地生产力。

In order to evaluate the effect of incorporation of forage with forest and shrubby on erosion control, runoff plots were constructed in 2001 in Jinsha River Experimentation Demonstration Plots. The results of three years showed that forages and forest had very significant effects on controlling runoff and soil loss. The vegetation could reduce runoff speed and increase rainfall penetration remarkably, thus could reduce runoff and erosion. After grain for green, soil nutrient increased, soil bulk density decreased, soil physical and chemical characteristics improved, and plot production promoted greatly due to the interception and capture of the lost soil nutrient by forage.