摘要
土壤抗冲性对喀斯特地区的水土保持和生态环境建设具有重要意义。以阔叶林、针叶林和灌草地的土壤为研究对象,采用人工模拟降雨和原状土冲刷试验法,研究不同植被覆盖条件下的土壤抗冲性动态变化特征及其影响因素。结果表明:①在降雨冲刷的2 min内,各植被类型土壤的产沙量最大,随后逐渐减少,在9 min后趋于稳定状态,产沙量随时间的变化总体表现为灌草地>针叶林>阔叶林,并且随坡度的升高而逐渐增多;②在坡度为15°时,灌草地的土壤抗冲性最低,且与阔叶林和针叶林相差较大,但在坡度为45°和4~12 min的降雨冲刷情况时,土壤抗冲性表现为阔叶林>灌草地>针叶林,不同植被条件下的土壤抗冲性存在差异,总体表现为:阔叶林的土壤抗冲性能最强,利于保持水土,针叶林次之,灌草地最弱;③不同植被条件下的土壤抗冲性随降水冲刷时间的增加而逐渐增强,坡度和根系尤其是径级>1 mm植被根系对土壤抗冲性具有重要的影响作用。
Soil anti-scourability is of great significance for soil and water conservation and ecological environment construction in Karst area.Taking the soils in broad-leaved forest,coniferous forest and shrub-grass land as the research objects,this paper researches the dynamic variation characteristics of soil anti-scourability and its influencing factors under different vegetation types in karst area by the artificial simulated rainfall and undisturbed soil scouring experiment.The results show that:(1)Within 2 min of rainfall scouring,the sediment yield of soil in different vegetation types is especially large,then gradually decreases,and reaches a stable state after 9 min.In general,the sediment yield of shrub-grass land was largest,followed by coniferous forest and broad-leaved forest,and the sediment yield of different vegetation types increases gradually with the increase of the slope.(2)The soil anti-scourability of shrub-grass land is lowest at the slope of 15°,which is obvious different from the broad-leaved and coniferous forest,but in the slope of 45°and within 4~12 min of rainfall scouring,the soil anti-scourability of broad-leaved forest is the strongest,followed by shrub-grass land and coniferous forest.Soil anti-scourability of different vegetation types are different,that is broad-leaved forest>coniferous forest>shrub-grass land.With strongest soil anti-scourability,the broad-leaved forest is beneficial to soil and water conservation.(3)The soil anti-scourability of different vegetation types increases gradually with the increase of the rainfall scouring time,and the slope and root system,especially the root of vegetation with more than 1 mm diameter,have important influences on the soil anti-scourability.
作者
韦小茶
龙小梅
唐欣
刘洋
肖杨
李洪广
WEI Xiaocha;LONG Xiaomei;TANG Xin;LIU Yang;XIAO Yang;LI Hongguang(School of Geography and Environment Science,Guizhou Normal University,Guiyang 550001,China)
出处
《人民珠江》
2020年第2期67-73,共7页
Pearl River
基金
贵州师范大学创新基金项目(YC〔2018〕026)
关键词
土壤抗冲性
植被类型
坡度
人工模拟降雨
原状土冲刷试验
喀斯特区
soil anti-scourability
vegetation types
slope
artificial simulated rainfall
undisturbed soil scouring experiment
Karst area
