渭北小流域水土保持措施的减沙效益

Sediment Reduction Effect by Soil and Water Conservation in Weibei Watershed

通过对渭北地区29个县、市、区的34条小流域水土流失的成因和分布规律的调查和资料分析,并对实施的各项水土保持措施的减沙量进行了计算。认为,渭北高原水土流失是多因素综合作用的结果,其中,侵蚀量的大小与10min最大雨强、地形坡度因子成正相关;人类活动具有二重性。34条流域的总减沙量为192.51万t,其中梯田埝也减沙量占减沙量的28.7％,林草为46.43％,工程措施为24.28％。

Describes soil and water losses caused by comprehensive actions of several factors. Among these, the erosive power is directly correlated to maximum rainfall within 10 minutes and the topographic slope.Human activities play a double roles on soil and water losses. Total sediment reduction amount up to 1925. 1 thousand tons in the whole Weibei watershed. In which the sediment reduction of terraces is 28.79%, of the forest and grasslands is 46.43% and of the engineering devices is 24.28%.