黄土高塬沟壑区典型小流域不同雨型水沙关系特征  

Relationship between runoff and sediment under different rainfall patterns in the small watershed on the tableland-gully region of the Loess Plateau

作　　者：郭小雪 田鹏[2] 杜敏 赵广举 穆兴民[1,3] 高鹏 卢小燕[4] GUO Xiaoxue;TIAN Peng;DU Min;ZHAO Guangju;MU Xingmin;GAO Peng;LU Xiaoyan(State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau,Institute of Soil and Water Conservation,Northwest A&F University,712100,Yangling,Shaanxi,China;College of Natural Resources and Environment,Northwest A&F University,712100,Yangling,Shaanxi,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,712100,Yangling,Shaanxi,China;Hydrological Survey Bureau of Ordos City of Inner Mongolia,017020,Ordos,Inner Mongolia,China)

机构地区：[1]西北农林科技大学,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,陕西杨凌712100 [2]西北农林科技大学资源环境学院,陕西杨凌712100 [3]中国科学院水利部水土保持研究所,陕西杨凌712100 [4]内蒙古自治区鄂尔多斯水文勘测局,内蒙古鄂尔多斯017020

出　　处：《中国水土保持科学》2022年第6期1-7,共7页Science of Soil and Water Conservation

基　　金：国家自然科学基金“黄土高塬沟壑区对比小流域植被恢复对水沙变化的驱动机制”(42177323);国家自然科学基金委黄河水科学研究联合基金“黄土高原水土保持措施潜力及其对河流水沙的调控机制”(U2243211);国家科技基础资源调查项目“中国南北过渡带综合科学考察”(2017FY100904)。

摘　　要：探究不同降雨类型下流域产流产沙特征及水沙关系,以黄土高塬沟壑区杨家沟小流域作为研究区,采用K-means聚类算法和判别分析法对流域1981—2010年的184场次降雨事件进行分类,用幂函数方法探究不同降雨类型的水沙关系特征。杨家沟小流域年径流量和输沙量都呈现显著减少趋势(P<0.01),相较1981—1989年,二者在1990—2010年的均值分别减少50.32%和55.64%。场次降雨事件可划分为3种类型:A雨型(小雨量、中历时、中降雨强度)、B雨型(大雨量、长历时、小降雨强度)和C雨型(中雨量、短历时、大降雨强度),其中A雨型是流域产流产沙的主要降雨类型。幂函数能较好地拟合不同雨型的径流深和输沙模数关系,A雨型的拟合效果优于B雨型。降雨量减少和植被覆盖率增加是杨家沟流域径流量及输沙量减少的主要原因,降雨量、降雨强度、降雨历时对流域产流产沙能力有重要影响。[Background]The Loess Plateau,one of the most severe soil erosive areas in the world,is discharging large amounts of sediment to the Yellow River,resulting in serious sedimentation of the downstream channel.Assessing the relationships between rainfall,runoff,and sediment in the watershed may provide critical insights for understanding hydrological and soil erosion processes which are vital to sustainable management of watershed.This study attempts to analyze characteristics of runoff and sediment yield and their relationship with different rainfall patterns in the Yangjiagou watershed on the tableland-gully region of the Loess Plateau.[Methods]This study applied the K-means clustering method and discriminant analysis method,and the rainfall events were classified using the runoff and sediment load data of the 184 rainfall events in the Yangjiagou watershed during 1981-2010.The power function was used to analyze the relationship of runoff and sediment.[Results]Annual runoff and sediment load demonstrated significant decreasing trend(P<0.01).Average annual value of the runoff and sediment load decreased by 50.32%and 55.64%in 1990-2010 compared to those during 1981-1989,respectively.The rainfall events were divided into three patterns.Pattern A was characterized by low rainfall amount(13.30-29.20 mm),medium duration(4.00-12.63 h)and medium rainfall intensity(1.80-5.00 mm/h).It included 149 rainfall events,accounting for 81%of the total rainfall events.Pattern B comprised of 32 rainfall events,accounting for 17%,which were characterized by high rainfall amount(48.73-75.05 mm),long duration(24.38-38.31 h)and low rainfall intensity(1.32-2.73 mm/h).Only 3 rainfall events belonged to pattern C,accounting for 2%of the total,and was characterized by medium rainfall amount(15.45-60.85 mm),short duration(0.57-4.40 h)and heavy rain intensity(27.65-38.60 mm/h).Pattern A was major rainfall pattern in the studied watershed,pattern B was similar to pattern A,and pattern C was extreme rainfall events.The proportions of the accumul

关 键 词：降雨类型 产流产沙 水沙关系 黄土高塬沟壑区 杨家沟小流域 

分 类 号：S152.1[农业科学—土壤学]