不同砾石含量塿土堆积体坡面侵蚀特征研究  

Erosion of Slopes of Lou Soil Stacks Different in Gravel Content

作　　者：赵满 王文龙 郭明明[1] 康宏亮 杨波 王文鑫 陈卓鑫 ZHAO Man;WANG Wenlong;GUO Mingming;KANG Hongliang;YANG Bo;WANG Wenxin;CHEN Zhuoxin(State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau,Institute of Soil and Water Conservation,Northwest A&F University,Yangling,Shaanxi 712100,China;Institute of Soil and Water Conservation,Chinese Academy of Sciences and Ministry of Water Resources,Yangling,Shaanxi 712100,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]中国科学院水利部水土保持研究所,陕西杨凌712100

出　　处：《土壤学报》2020年第5期1166-1176,共11页Acta Pedologica Sinica

基　　金：国家重点研发计划项目(2016YFC0501604);国家自然科学基金项目(40771127,41761062)资助。

摘　　要：为明确砾石含量对关中塿土堆积体坡面径流和侵蚀特性的影响,采用室内模拟降雨试验方法,以土质坡面为对照,研究了10%、20%、30%三种砾石含量堆积体坡面的侵蚀特征。结果表明:(1)1.0 mm·min^-1雨强下,10%砾石含量时初始产流时间最大,雨强>1.0 mm·min^-1时,各坡面初始产流时间在10%砾石含量时最小;(2)各砾石含量坡面平均流速均随雨强增大而增大,1.0和2.5 mm·min^-1雨强条件下10%砾石含量坡面流速最大,而1.5和2.0 mm·min^-1雨强下,含砾石坡面流速较土质坡面分别减少15.3%~21.2%和13.6%~14.1%;(3)不同雨强条件下各含砾石坡面含沙量在产流前期(0~6 min)急剧下降;产流6 min后,含沙量在1.0、1.5 mm·min^-1雨强下逐渐趋于稳定,在2.0、2.5 mm·min^-1雨强下呈多峰多谷的变化,该时期砾石主导产沙过程;(4)次降雨侵蚀量随雨强增大呈显著的幂函数关系;而随雨强的增大各砾石坡面侵蚀量较土质坡面分别减少22.4%~42.6%、8.2%~66.3%、2.2%~56.5%和45.0%~68.3%。该研究可为关中地区堆积体坡面水蚀模型的建立提供理论依据。【Objective】During the processes of production and construction in Guanzhong Region,a large number of stacks of Lou soil were formed.Gravel in the stack is an important factor affecting soil erosion on stack slopes in characteristic.Therefore,this study was designed to explore impacts of gravel concentration on runoff and sediment yielding processes on slopes of Lou soil stacks different in gravel content.【Method】In this paper,artificial rainfalls were simulated indoor,different in intensity(1.0 mm·min^-1,1.5 mm·min^-1,2.0 mm·min^-1 and 2.5 mm·min^-1),to explore their effects on runoff and sediment yield on slopes of Lou soil stacks different in gravel content(0,10%,20%and 30%).The experiment had test plots set up,5 m×1 m×0.6 m in area and 25°in slope gradient.The nozzles of the artificial rainfall simulator were 18 m high over the slopes,spraying water evenly(more than 80%in evenness).Rainfall intensity were calibrated before the start of each test to ensure that the deviation of the actual rainfall intensity in the test was kept less than 5%of the designed rain intensity for the test.During the test,flow velocity of the runoff on the slope was measured with the dyeing method,width of the flow with a steel ruler,duration of runoff and sediment collection recorded with a stopwatch,and quantity of the samples weighed on an electronic scale.【Result】Results show:(1)runoff lasted the longest on the Lou soil slope 10%in gravel content under rainfall 1.0 mm·min^-1 in intensity,and the shortest under rainfall lower than 1.0 mm·min^-1 in intensity;(2)mean flow velocity of runoff increased with rising rainfall intensity on all the gravel-containing slopes regardless of gravel content.The flow velocity on the slope 10%in gravel content was the highest under rainfalls 1.0 and 2.5 mm·min^-1 in intensity,and 15.3%-21.2%and 13.6%-14.1%lower than that on the slope under rainfall 1.5 and 2.0 mm·min^-1 in intensity,respectively;(3)sediment content in runoff dropped drastically during the initial period(0-6 m

关 键 词：降雨强度 砾石含量 径流产沙 塿土 

分 类 号：S157.1[农业科学—土壤学]