密云水库上游石匣小流域水土流失综合治理措施研究

坡面处理措施及土地利用方式是控制水土流失最重要的影响因素,通过合适的坡面措施与合理的土地利用方式可以有效地抑制土壤侵蚀,保护土地资源,改善生态坏境。论文通过对石匣小流域不同处理的径流试验小区的实测资料分析,研究了坡面综合水土保持措施对水土流失的影响。研究表明,与坡耕地、开荒地相比,梯田和水平条可以有效地拦蓄地面径流,控制水土流失,减沙率可达64.83%~91.81%,并且阴坡上的水平条的蓄水保土作用好于阳坡,有土埂的大水平条的减水拦沙效率好于无土埂的水平条;综合水保措施的水土保持效益更高,对径流量的拦蓄率高达96.21%~99.38%,并且进行综合措施处理的坡面的土壤侵蚀模数都小于水利部发布的北方土石山区允许土壤流失量200t/km².a;对坡面的自然封禁能够有效地控制坡面水土流失;同时由于综合水保措施很大程度上改变了原有的地形,坡度对水土流失的影响不明显。

Study on Comprehensive Control Measures of Soil Erosion about Shixia Small Watersheds in the Upper Miyun Reservoir

The control measures of the slope land and types of land use are the most important factors for controlling water and soil loss,and the appropriate control measures of the slope land and types of land use could control soil erosion,protect land resource,and improve the environment effectively.In this study,based on the survey data of runoff plots,the effect of integrated water and soil conservation measures on slope surface on water and soil loss was researched.The results showed that compared with the slope land,the sediment reduction rate of terrace and narrow terrace reaches 64.83%-91.81%,this shows terrace could control soil erosion effectively,and the water and soil reduction benefits from terrace on the shady slope are better than the terrace on the sunny slope and the wide narrow terrace with ridge is better than the one without ridge.The water and sediment benefits from comprehensive water and soil conservation measure are very high,which can get to 96.21%-99.38%.At the same time,the soil erosion modulus of runoff plots with comprehensive control measure is less than the soil loss tolerance of 200t/km²·a in earthy-rocky mountain area of northern China,which is promulgated by the Ministry of Water Resources of the People's Republic of China.The natural prohibition can also control water and soil loss effectively,but as a result of comprehensive control measure induced changes of the slope surface shape,slope grade has less impact on water and soil loss.