降雨与流域产沙——黄土高原产沙模型研究之一

本文以黄土高原强烈侵蚀区的孤山川流域为研究区,经广泛实地考察、遥感解释及30年实测水文资料分析认识流域产沙特征,根据这些特征提出流域产沙模型结构为C·R=S。再据实测降雨与流量变化关系提出可能影响流域产沙的降雨特性因子,用多元逐步回归分析方法确定主导降雨特性因子为P_m和I_a,降雨-产沙关系式为S=585.80P_m~(1.2856)I_a~(0.8875)。     

Model Study of Basin Soil Loss (BSL) in the Loess Plateau of China (Ⅱ)

According to the influence of underlayer factor upon the basin erosion and in the support of Geographic Information System (GIS) of Loess Plateau(LPIS), the Gushanchuan Basin is divided into several regions with different erosion intensity. Correlating them to the BSL quantity, the complete soil loss model is established. By using this model, the soil loss quantity of the whole basin as well as each erosion intensity region can be estimated.     

Model Study of Basin Soil Loss (BSL) in the Loess Plateau of China (Ⅰ)

Rain is the main motive force of erosion in the Loess Plateau of China. The relationship between rain and basin soil loss (BSL) is the base for establishing BSL model. Based on areo image interpretation, site investigation and analysis of 30-year rain-hydrological data of the study area——the Gushanchuan River Basin which is a branch of the middle reaches of the Yellow River basin as well as one of the intense erosion centres, the BSL features have been revealed. According to the features, the structure of the BSL model is proposed as follows: C·R =S, where C, R and S represent the factor of underlayer, rain and BSL quantity, respectively.Then by using the methods of multivariate statistical analysis, the dominant rain specific elements that affect the BSL and the corresponding formula of the relationship between rain and BSL have been determined as P_m and I_a, and respectively. With this formula the BSL quantity of every rainfall can be estimated. The estimated accuracy can be satisfied after correc     

下垫面与侵蚀强度及其产沙量——黄土高原产沙模型研究之二

本文介绍如何根据下垫面因子对流域产沙的影响,在地理信息系统支持下,将流域划分为不同侵蚀强度区,并使其与流域总产沙量相联系,建立完整产沙模型。利用该模型可以预报每一场降雨后的流域总产沙量及各侵蚀强度区的产沙量。