水土保持对王家沟流域山洪形成影响的研究

Study on Influence of Soil and Water Conservation on Mountain Torrents in Wangjiagou Watershed

由多种水保因素共同作用的水文现象具有相当大的不确定性,同时也存在一定的规律性。因此水文现象的研究往往依靠经验方法,而且结果也未必准确。文章利用HEC-HMS水文模型及ARCGIS平台,对分辨率为30m的DEM数据进行了预处理和数字流域的提取,并将王家沟流域划分为7个子流域,结合对应的土地利用及土壤类型数据,生成水文模型的基本计算单元。采用Green and Ampt法+SCS曲线法+马斯京跟法+退水曲线法进行模拟,定量探讨了植被条件和耕作方式等典型水土保持措施实施效果对该流域山洪的影响。分析表明,流域内林地的增加会导致土壤入渗率的增加,植被退化会导致叶面积指数的减小进而减小树冠截流量;结论可对山西省山洪灾害分析评价工作及其山丘区洪水预报工作提供技术指导和理论支持。

The hydrological phenomena,which are caused by many factors of water and soil conservation,is considerable uncertainty and some regularity.Therefore,the study of hydrological phenomena often relies on empirical methods and the results may not be accurate.Using HEC-HMS hydrological model and ARCGIS platform,this paper carried on the pretreatment and extraction of digital watershed resolution of 30 m DEM data,and it divided the Wangjiagou basin into seven subbasins.Combined with land use and soil type data,this paper generated a basic computing unit of hydrological model.Using Green and + Ampt + SCS curve method + Muskingum+ back water curve method,this paper discussed the effect of the implementation of typical soil and water conservation measures such as vegetation conditions and farming methods on themountain torrents.The results showed that the increase of the woodland in the basin could lead to the increase of soil infiltration rate,and the degradation of vegetation could lead to the decrease of the leaf area index and canopy interception rate.The conclusion could provide technical guidance and theoretical support and evaluation work of flood forecasting work in Hilly areas.