基于MUSLE模型的流域土壤侵蚀计算

发布时间：2018-03-02 10:40

本文关键词： MUSLE 泥沙河道演算土壤侵蚀模型　出处：《南京师范大学》2015年硕士论文　论文类型：学位论文

【摘要】：水土流失是流域非点源污染的主要驱动力,土壤侵蚀本身也是非点源污染的一种主要类型与方式。综合利用遥感、GIS技术,研究流域尺度土壤侵蚀定量评价方法,对流域水土资源管理以及非点源污染控制具有重要的意义。MUSLE (Modified Universal Soil Loss Equation)是美国土壤保护研究所开发的流域尺度土壤侵蚀计算模型,该模型综合考虑了影响土壤侵蚀状况的土壤可蚀性、坡度坡长、植被覆盖和管理措施、地表径流等因子,目前广泛应用于流域尺度水土流失过程模拟计算。本文以MUSLE模型为核心,在流域土壤侵蚀过程分析的基础上开发了可用于于流域非点源污染快速估算的分布式土壤侵蚀过程模型。本文的研究内容与成果如下：(1) 在流域土壤侵蚀过程分解和集成分析的基础上,分析了MUSLE模型的基本原理,研究了模型计算涉及的土壤可蚀性因子、植被覆盖因子、保持措施因子、坡度坡长因子等参数的计算方法,研究了基于泥沙沉积和冲刷计算的河道泥沙水力学演算方法,分析总结了流域尺度土壤侵蚀和泥沙传输分布式计算的相关理论,构建了模型开发的基础理论框架；(2) 研究了土壤侵蚀分布式计算的模型结构和数据组织方法,在Microsoft Studio.NET编程环境下,采用面向对象的C#语言,借助模块化的建模思想,构建了由坡面产沙模块、河道输沙模块为核心的流域尺度分布式土壤侵蚀计算模型；利用GIS的空间数据处理功能,以ArcgisEngine为辅助平台,开发了分布式计算的数据获取和组织、结果可视化显示、模拟结果校正等功能模块；(3) 分别以中田舍流域和潋水河流域为研究区,利用本文开发的模型对两个流域的土壤侵蚀和泥沙河道产出过程进行了分布式的计算,利用观测数据对模拟结果进行了校正和验证,并对模型适用性进行了评价。对中田舍流域2009-2014年进行模拟证明,由于受到清淤等人为措施的影响,总体模拟精度较低。但在排除受人为措施影响较大的年份,年产沙量模拟值和实测值相比较,决定系数(R2)和纳什系数(Ens)分别可以达到0.96和0.89,月产沙量的R2和Ens分别为0.92和0.69,模拟精度较高；为了进一步验证模型,选择潋水河流域2000-2009年产沙过程再次进行模拟验证,年产沙量R2为0.88,Ens为0.84；月产沙量R2为0.9,Ens为0.82,模拟精度较高,说明模型在两个流域具有较好的适用性。
[Abstract]:Soil erosion is the main driving force of non-point source pollution, and soil erosion itself is a main type and mode of non-point source pollution. It is of great significance to water and soil resources management and non-point source pollution control in watershed. MUSLE modified Universal Soil Loss Equation.MUSLE is a watershed scale soil erosion calculation model developed by the United States soil Conservation Institute. The model takes into account such factors as soil erodibility, slope length, vegetation cover and management measures, surface runoff and so on. At present, it is widely used in watershed scale soil erosion process simulation. The MUSLE model is used as the core in this paper. Based on the analysis of watershed soil erosion process, a distributed soil erosion process model for rapid estimation of non-point source pollution in watershed is developed. The research contents and results are as follows: 1) decomposition in watershed soil erosion process. And integration analysis, The basic principle of MUSLE model is analyzed, and the calculation methods of soil erodibility factor, vegetation cover factor, conservation measure factor, slope length factor and so on are studied. Based on the calculation of sediment deposition and erosion, the hydraulic calculation method of river channel sediment is studied, and the relevant theories of distributed calculation of soil erosion and sediment transport in river basin are analyzed and summarized. The model structure and data organization method of soil erosion distributed computing are studied in this paper. In the Microsoft Studio.NET programming environment, the object-oriented C # language is adopted and the modular modeling idea is used. A watershed scale distributed soil erosion calculation model with sediment yield module and channel sediment transport module as the core is constructed, and the data acquisition and organization of distributed computing are developed using spatial data processing function of GIS and ArcgisEngine as the auxiliary platform. The results show that the simulation results correction and other functional modules, such as simulation results correction, are used in the distributed calculation of soil erosion and sediment channel production processes in the middle Tianshe and Lianshui river basins, respectively, using the model developed in this paper. The simulation results were calibrated and verified by observation data, and the applicability of the model was evaluated. The simulation of Zhongtianshe Basin from 2009-2014 proved that due to the influence of artificial measures such as desilting, The simulation accuracy of the whole simulation is low. But in the year when the anthropogenic measures are excluded, the simulated value of annual sediment yield is compared with the measured value. The determinant coefficients R2) and Nash coefficients can reach 0.96 and 0.89, respectively, and the R2 and Ens of monthly sediment yield are 0.92 and 0.69, respectively, so the simulation accuracy is higher. In order to further verify the model, the Lianshui River basin sediment production process from 2000 to 2009 is selected to be simulated again. The annual sediment yield R2 is 0.88N Ens, and the monthly sediment yield R 2 is 0.92%. The simulation accuracy is high, which indicates that the model is suitable for the two watersheds.
【学位授予单位】：南京师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S157

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