基于SWAT模型的延河流域径流侵蚀能量空间分布

发布时间：2019-05-23 19:35

【摘要】：降雨侵蚀力是通用土壤流失方程(universal soil loss equation,USLE)等流域土壤侵蚀模型中应用最广泛的侵蚀动力因子,但仍具有一定的局限性,相比之下,径流侵蚀功率可以更充分地反映地表水力侵蚀动力的综合作用。分析径流侵蚀功率的空间分布,以期从能量的角度阐明流域侵蚀的分布情况,研究流域空间侵蚀的特征。该研究运用SWAT模型在延河流域的模拟结果,将次暴雨径流侵蚀功率推广到年尺度,提出年径流侵蚀功率的概念,并研究年径流侵蚀功率的空间分布规律及尺度效应。研究结果表明:在延河流域年径流侵蚀功率的空间分布具有"支流大、干流小;上游大、下游小"的特点;将子流域出口断面控制面积作为空间尺度因子,与径流侵蚀功率拟合,呈幂函数关系,空间尺度效应阈值在155 km2;将子流域出口断面以上河长作为空间尺度因子,与径流侵蚀功率拟合,呈指数函数关系,且干、支流的空间尺度效应不同。研究结果从能量角度阐明了延河流域水力侵蚀动力的空间分布,为在延河流域不同地区进行针对性的水土资源管理、水土保持工程建设提供理论支持。
[Abstract]:Rainfall erosivity is the most widely used erosion dynamic factor in watershed soil erosion models such as the general soil loss equation (universal soil loss equation,USLE), but it still has some limitations. Runoff erosion power can more fully reflect the comprehensive effect of surface hydraulic erosion power. The spatial distribution of runoff erosion power is analyzed in order to clarify the distribution of basin erosion from the point of view of energy and to study the characteristics of spatial erosion in watershed. Based on the simulation results of SWAT model in Yanhe River Basin, the erosion power of rainstorm runoff is extended to annual scale, the concept of annual runoff erosion power is put forward, and the spatial distribution law and scale effect of annual runoff erosion power are studied. The results show that the spatial distribution of annual runoff erosion power in Yanhe River Basin is characterized by "large tributary, small main stream, large upstream and small downstream". The control area of the outlet section of the sub-basin is taken as the spatial scale factor, which is fitted with the runoff erosion power, and the spatial scale effect threshold is at 155 km2;. The river length above the outlet section of the sub-basin is taken as the spatial scale factor, which is fitted with the runoff erosion power in an exponential function, and the spatial scale effect of the dry and tributaries is different. The research results clarify the spatial distribution of hydraulic erosion power in Yanhe River Basin from the point of view of energy, and provide theoretical support for the management of soil and water resources and the construction of soil and water conservation projects in different areas of Yanhe River Basin.
【作者单位】：西安理工大学西北水资源与环境生态教育部重点实验室;中国科学院水利部水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室;
【基金】：国家重点研发计划(2016YFC0402404) 国家自然科学基金重点项目(41330858) 陕西省教育厅重点实验室科研计划项目(16JS086) 西安理工大学博士创新基金(310-252071505)
【分类号】：S157.1

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