摘要
亚高山草甸土广泛分布于川西高原的深切河谷斜坡地带,受特殊的土体结构和气候条件影响,浅层草甸土在雨季常发生解体并逐级溜滑,造成大面积的土体侵蚀和草甸退化,是川西高原生态脆弱的典型表现之一。在亚高山草甸土浅层溜滑侵蚀野外原型调查的基础上,结合TOPMODEL模型,考虑汇水区内地形与地下水流侧向流动的特点,并考虑渗透压力的影响改进了TRIGRS的无限斜坡地质力学模型,提出了适用于降雨型亚高山草甸土浅层溜滑侵蚀的空间分布预测模型(Ad-TSMS模型)。通过模型验证表明:Ad-TSMS模型的预测结果与野外调查的实际浅层溜滑侵蚀灾害点编录数据的吻合度更高,说明对TRIGRS模型的改进有效提高了模型的预测精度。本研究对准确地预测亚高山草甸土浅层溜滑侵蚀的空间分布,制定相应的草甸土浅层溜滑侵蚀防治措施和合理的高原生态保持管理制度,具有一定的理论和现实意义。
Subalpine meadow soils are widely distributed in the deep river valley slopes of the western Sichuan plateau,and due to the special soil structure and climatic conditions,shallow meadow soils often disintegrate and run out in the rainy season.This phenomenon causes extensive soil erosion and meadow degradation,which is one of the typical manifestations of ecological fragility in the western Sichuan plateau.Based on the field prototype investigation,this study proposes a spatial distribution prediction model(Ad-TSMS model)for shallow slide erosion risk of rainfall-type subalpine meadow soils on the basis of the erosion mechanism.The Ad-TSMS model is combined with the TOPMODEL model to effectively consider the lateral recharge of topography and groundwater flow in the catchment area,and by considering the influence of seepage pressure,the infinite slope of TRIGRS is improved as well.Through comparison and verification,the prediction results of the Ad-TSMS model are in better fit with the compiled data of soil erosion points from the field survey,indicating that the improvement of the TRIGRS model has effectively improved the prediction accuracy.The study has theoretical and practical significance for accurately evaluating the distribution of shallow slide erosion of subalpine meadow soil,formulating corresponding meadow soil erosion control measures,and a reasonable management system for plateau ecological conservation.
作者
邓远东
郭健
易鹏飞
DENG Yuandong;GUO Jian;YI Pengfei(State Key Laboratory of Geo-hazard Prevention and Geo-environment Protection,Chengdu University of Technology,Chengdu 610059,China;Sichuan Institute of Geological Engineering Investigation Group Co.,Ltd.,Chengdu 610072,China)
出处
《安全与环境工程》
CAS
CSCD
北大核心
2021年第3期170-178,共9页
Safety and Environmental Engineering
基金
国家自然科学基金青年基金项目(41807292)。
