模拟降雨下林下覆被结构对产流产沙过程的影响  

Effect of Mulch Structure on Runoff and Sediment Yield Under Simulation Rainfall

作　　者：朱方方 秦建淼 朱美菲 张友焱[2] ZHU Fangfang;QIN Jianmiao;ZHU Meifei;ZHANG Youyan(College of Soil and Water Conservation,Beijing Forestry University,Beijing 100083;Institute of Ecological Protection and Restoration,Chinese Academy of Forestry Sciences,Beijing 100091)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]中国林业科学研究院生态保护与修复研究所,北京100091

出　　处：《水土保持学报》2023年第3期10-18,共9页Journal of Soil and Water Conservation

基　　金：“十四五”国家重点研发计划项目(2022YFF1302504)。

摘　　要：植被具有良好的水土保持效益,深入了解覆被结构特征与产流产沙关系是研究植被防蚀功能的基础。以鄂中地区典型森林植被为对象,通过人工模拟降雨试验研究5种覆被结构(灌木、草本、枯落物、灌木+草本、灌木+草本+枯落物)和侵蚀性降雨(60,90,120 mm/h)对坡面侵蚀产沙过程的影响。结果表明:(1)坡面产流率、产沙率随降雨时间先迅速增大,后缓慢增大,最后达到稳定趋势。降雨强度是坡面侵蚀产沙的主导因素,与产流时间、产流率和产沙率呈显著正相关关系(p<0.01)。(2)在有/无枯落物存在的情况下,植被覆盖度、植株密度分别是坡面产流产沙的主要影响因素。径流含沙量在不同覆被结构覆盖下表现为:草本>灌木>枯落物>灌木+草本>灌草枯。(3)结构特征参数对产流产沙影响的优先等级为覆盖度、生物量、植株密度、多样性指标,即水平结构>竖直结构>物种组成>空间格局。研究结果旨在揭示覆被结构对坡面侵蚀产沙的作用机理,为南方林地土壤侵蚀模型的构建提供科学参考。Vegetation has good function of soil and water conservation.Careful understanding the relationship between the structural characteristics of vegetation and the production of runoff is the basis for studying the erosion control function of vegetation.In this paper,the effects of five vegetation structures(shrubs,herbs,litter,shrubs+herbs,shrubs+herbs+litter)and erosive rainfall(60,90,120 mm/h)on the process of erosion were investigated by artificial simulated rainfall experiments with typical forest vegetation in Central Hubei.The results showed that:(1)The runoff and sediment yield increased rapidly at first,then increased slowly with the rainfall time,and finally reach a stable trend.Rainfall intensity was the dominant factor of slope erosion and sand production,and showed a significant positive correlation with flow production time,flow production rate and sand production rate(p<0.01).(2)With or without litter,vegetation coverage and plant density were the main factors affecting runoff and sediment yield on the slope.The sediment concentration of runoff under different covering structures was as follows:herb>shrub>litter>herb+shrub>shrub and grass withered.(3)The priority of structural characteristic parameters on runoff and sediment yield was:coverage,biomass,plant density,diversity index,that was,horizontal structure>vertical structure>species composition>spatial pattern.The results of the study aim to reveal the mechanism of the role of vegetation structure on slope erosion,and provide scientific reference for the construction of soil erosion models in southern woodlands.

关 键 词：土壤侵蚀 覆被结构 产流产沙 函数关系 

分 类 号：S714.7[农业科学—林学]