头塘小流域退耕地不同植被恢复模式坡面径流和产沙特征分析

Analysis of the Flow and Sediment Characters of Different Restored Vegetation Types in Toutang Catchment

建立坡面径流观测场,对头塘小流域退耕还林中几种不同植被恢复模式的径流量、产沙量进行了定点观测。结果表明:不同植被恢复模式、不同坡度等级、两者的交互效应对坡面径流系数、产沙量影响均比较显著。乔灌草模式在产沙量、径流系数方面均为最小,其水土保持功能最大,其次为灌草模式。随着坡度的增大,径流系数与产沙量均有增大趋势。进一步研究和完善乔灌草的生态经营技术体系,提高该类退耕种植植被恢复模式的调蓄降雨能力,对指导退耕还林及植被经营有重要的意义。

Several long term plots for different restored vegetation types in Toutang catchment were set up, and the amount of the flow and sediment for several years were observed. The results showed that the flow coefficient and the sediment content were greatly influenced by different restored vegetation types, different slopes, and the interaction between them. The mode of tree ＋ bush ＋ grass had the least sediment content, so it had the most prominent effect on holding water and soil. Along with the slope increased, the flow coefficient and sediment content all had increased. To up-grade the capacity of holding the rainfall, further studies on the ecological techniques of tree ＋ bush ＋ grass were needed, and they could be guidelines to the engineering of converting farmland to forest in the area.