基于水文连通性的流域输沙量评估——以堵河流域为例  

Evaluation of Watershed Sediment Yield Based on Hydrological Connectivity——A Case Study of Upper Duhe Watershed

作　　者：张媛平 刘成帅 肖海兵 王剑[1] 史志华[1] ZHANG Yuanping;LIU Chengshuai;XIAO Haibing;WANG Jian;SHI Zhihua(College of Resources and Environment,Huazhong Agricultural University,Wuhan 430070,China)

机构地区：[1]华中农业大学资源与环境学院,武汉430070

出　　处：《水土保持研究》2022年第3期64-70,共7页Research of Soil and Water Conservation

基　　金：国家自然科学基金“流域水文连通性对侵蚀产沙过程的影响与机理”(41930755)。

摘　　要：水文连通性是指泥沙、营养盐等各种物质以水为载体,在空间异质景观或斑块间进行迁移、传输或扩散的便利程度,对流域产沙具有重要影响。为评估基于水文连通性模拟流域输沙量的可行性,以堵河流域为研究对象,分析了1990—2010年流域土壤侵蚀、水文连通性的时空变化特征,并以此估算了流域输沙量。结果表明:1990—2000年流域土壤侵蚀模数与连通程度不断增加,连通性等级主要由低和中低连通性转变为中高和高连通性。2000—2010年流域连通程度和土壤侵蚀模数均呈现不断减小的趋势。此外,输沙量估算值与实测值具有显著的线性关系(R^( 2)=0.92),但由于未考虑水库、湖泊等对泥沙输移的拦截效应,输沙量估算值要高于实测值,后续研究需将其纳入模型以更准确地评估流域输沙量。研究结果对于提高模型的适用性以及理解流域泥沙输移过程具有重要意义。Hydrological connectivity refers to the convenience of sediment,nutrients and other materials to migrate,transport or diffuse between spatial heterogeneous landscapes or patches with water as the carrier,which has an important impact on sediment yield.The spatial and temporal variation characteristics of soil erosion and hydrological connectivity were analyzed.Furthermore,the sediment yield of the watershed was further estimated based on the empirical model related to connectivity index and sediment delivery ratio.The results show that the soil erosion modulus and IC index increased continuously during the period 1990—2000;the connectivity level increased from low connectivity and medium-low connectivity to medium-high connectivity and high connectivity;both IC value and soil erosion modulus showed a decreasing trend during the period 2000—2010;in addition,there was a significant linear relationship between the estimated sediment yield and the measured value(R ^(2)=0.92),but the overestimated sediment yield was observed in this study,which might be related to the interception effect of reservoirs and lakes;it is necessary to incorporate them into the model for further research to more accurately evaluate sediment yield.These results are of the great significance for improving the applicability of the model and understanding the sediment yield processes in the watershed.

关 键 词：土壤侵蚀 水文连通性 输沙量 堵河流域 IC指数 

分 类 号：P333.4[天文地球—水文科学]