黄土坡面降雨产流产沙过程及其响应关系研究

降雨及其产生的径流是引起黄土高原土壤侵蚀的主要动力,开展黄土区降雨产流产沙过程研究可为土壤侵蚀过程模型研发奠定基础,为该区水土保持与生态建设提供重要科学依据。该文基于收集分析子洲径流试验站天然非恒定降雨、产流、产沙过程观测资料,应用非线性模拟技术,对黄土坡面降雨产流产沙动态变化过程及响应关系进行了研究,结果表明,黄土坡面累积降雨量随降雨历时的变化过程、累积径流深随产流历时的变化过程、累积侵蚀产沙模数随产沙历时的变化过程、累积径流深变化过程对累积降雨量变化过程的响应、累积侵蚀产沙模数变化过程对累积径流深变化过程的响应均呈现为非线性关系,可分别划分为两种类型,并分别可用扩展S型曲线模型和扩展幂函数模型进行数学描述。

Research on Processes and Responses of Rainfall-Runoff-Sediment Yield on Loess Hillslope

Rainfall and runoff are the main dynamic factors which cause soil erosion on the Loess Plateau.Research on processes of rainfall,runoff and sediment yield can serve as development of process-based mode of soil erosion,soil and water conservation,and ecology construction on loess region.Based on analyzing the data of natural unsteady rainfall,runoff and sediment yield processes observed in Zizhou field experimental station,and applying non-linear modelling technology,the dynamic variational processes and responded relationship of rainfall-runoff-sediment yield on loess hillslope are studied.The research results show that the variation processes of accumulated rainfall amount with rainfall time,the variation processes of accumulated runoff depth with runoff time,the variation processes of accumulated erosion modulus with sediment yield time,the responses of variation processes of accumulated runoff depth to variation processes of accumulated rainfall amount,the responses of variation processes of accumulated erosion modulus to variation processes of accumulated runoff depth are all displayed with non-linear relationships.All of them can be divided into two types and can be described with extanded S curve model and extanded power function model respectively.