基于水库沉积物特征及WaTEM/SEDEM模型的贵州喀斯特小流域土壤侵蚀时空变化  

Spatial and Temporal Changes of Soil Erosion in Small Watershed in Guizhou Karst Based on Characteristics of Reservoir Sediments and WaTEM/SEDEM Model

作　　者：邱安安[1] 罗耀[1] 王红亚[1] QIU Anan;LUO Yao;WANG Hongya(College of Urban and Environmental Sciences,Peking University,Beijing 100871,China)

机构地区：[1]北京大学城市与环境学院,北京100871

出　　处：《水土保持研究》2019年第1期14-21,共8页Research of Soil and Water Conservation

基　　金：国家自然科学基金重大国际合作项目(41571130043)

摘　　要：全面认识长时间尺度的贵州喀斯特地区土壤侵蚀时空变化对土壤侵蚀治理具有重要意义。以贵州松官流域为研究对象,使用土壤侵蚀分布式模型WaTEM/SEDEM分6个阶段模拟了过去1986—2015年的土壤侵蚀变化,并将其与松官水库沉积物揭示的侵蚀强度进行了对比。结果表明:利用WaTEM/SEDEM模型模拟得到的产沙量与实测值相近,显示模型在喀斯特地区具有较好的适用性;过去30年间松官流域土壤平均侵蚀模数为21.33t/(hm2·a),侵蚀强度经历了先加剧后减缓的过程,最强烈的侵蚀出现在1996—2000年;流域南部的耕地地区是松官流域土壤侵蚀的主要来源,占土壤侵蚀总量的85.09%,而流域北部的林草地侵蚀较弱;模型结果与沉积物记录具有较好的一致性,皆反映出土地利用相较降雨对土壤侵蚀影响更大,未来对喀斯特地区的水土保持更应关注土地利用的变化。Understanding the temporal and spatial changes of soil erosion in the karst area of Guizhou Plateau is a key requirement for managing against soil erosion.A spatially distributed soil erosion and sediment delivery model(WATEM/SEDEM)was applied to investigate temporal-spatial changes in soil erosion under six scenarios during the past 30 years in Songguan Watershed.The results showed that the sediment yield simulated by using the WaTEM/SEDEM model and observed values fitted well,showing that the model had a good predictability and practicability in karst regions.The average soil erosion in Songguan watershed was 21.33 t/(hm^2·a)and the intensity of soil erosion decreased firstly and then increased during the past 30 years.The major sediment source was dryland,accounting for 85.09%of the total sediment yields while the erosion in northern forestland and grassland was relatively slight.The simulated sediment yields were in good agreement with the sediment records.They both demonstrated that land use had a greater impact on soil erosion rather than rainfall.The study suggests that attention should be given to the changes of land use spatial pattern when applying soil conservation policies in karst regions.

关 键 词：地理学 侵蚀模数 WaTEM/SEDEM模型 沉积物 贵州喀斯特 

分 类 号：S157[农业科学—土壤学] F301.24[农业科学—农业基础科学]