山西省水土流失治理的战略抉择

Strategy Choice for Control of Water Loss and Soil Erosion in Shanxi

黄土丘陵山区占山西全省土地面积的80%,水土流失面积占全省土地面积的69%。山西省是我国水土流失最严重的省份之一。黄河流经山西的大北干流河段,占黄河干流长度的11.9%,而该区向黄河输入泥沙量达2.9亿t,约占全省入黄泥沙量的80.6%,占黄河总泥沙量的18.12%,是水土异常强烈流失区,侵蚀模数达到10000～15000t/km2。把山西西部沿黄丘陵山区作为水土治理特区重点治理,对改善山西和黄河生态具有重要战略意义。总结半个世纪以来黄土高原治理水土流失的经验,只有由治水为主,转向植树、种草恢复植被,治山治土,综合治理,遵循地带性适树、适草原则,森林覆盖率达到30%,植被覆盖率达到60%,区域水土流失控制在1000～1500t/km2,水土流失才可能得到全面控制。

Loess hilly area accounts for 80% land area and soil erosion area accounts for 69% of the total land area in Shanxi,so Shanxi is one of the most serious soil erosion provinces in China.Though Dabei main course in Shanxi accounts for 11.9% of the total main course of Yellow River and its basin area 2.5% of that of the Yellow River,its sediment input capacity of 290 million tons accounts for 80.6% of the total sum of the whole province and 18.12% of the total for the Yellow River,Shanxi is an area of ultra serious water loss and soil evosion.Taking hilly area along Yellow River in western Shanxi as control focus of water loss and soil erosion,it is of great importance to improve the ecology in the province and of the Yellow River.In the paper,experience was summed up and the conclusion is that plantation of trees and grasses,erosion control and integrated management around hills is the only choice.Only when we forllow the principles of the right tree and grasses for individual land and the forest coverage rate reaches 30%,vegetation cover 60% and area erosion module below 1 000～1 500 t/km2,is it possible to completely control water loss and soil erosion.