Assessment Of The Landslide Susceptibility In Xiuning County,Anhui Province Using GIS And Spatial Multicriteria Decision Analysis

Landslide,as one of the frequent geological disasters in China,not only brings serious casualties and property losses,but also causes ecological imbalance,and the post-disaster recovery work is complicated and expensive.Therefore,it is urgent and necessary to study landslide geological hazards,and it is an important means of landslide disaster prevention and mitigation under the current technical conditions to evaluate the susceptibility of landslide geological hazards and to make sure that the hazards are in advance and prevented in advance.Xiuning County of Anhui Province is located in the deep part of the southern Anhui mountains.Historically,landslides occurred frequently,which posed a serious threat to the safety of local people's lives and property.This paper analyzed the geographical and human-influenced factors of landslides in Xiuning County,determined the factors for evaluating the vulnerability of landslide disasters in the County,calculated the weight of each factor,designed and calculated the landslide prediction models using GIS and spatial multi-criterion decision analysis techniques,and then analyzed the regional landslide zonation of the County.The main research work and achievements are as follows:(1)A spatial database of the known landslides and evaluation factors in Xiuning County were established.The evaluation factors include faults,rivers,geomorphic units,rainfall,slope aspects,roads,lithology,land uses and slopes.(2)The evaluation indicators of landslide susceptibility in the County included nine factors such as fault,river,geomorphic unit,rainfall,slope aspect,road,lithology,land use and slope.The weights of these nine indicators were obtained by analytic hierarchy process(AHP)as follows: 0.2087,0.1595,0.0408,0.0302,0.0582,0.2386,0.1235,0.0646 and 0.0758 respectively.These nine environmental or human impact factors are spatially related to the distribution of the landslides in the County.(3)When the parameter p = 2,the spatial TOPSIS model had a good prediction effect and was used for the evaluation and zoning of landslide hazard susceptibility in Xiuning County.In Xiuning County,landslide prone areas are mainly distributed around roads,rivers and faults.The remaining areas are the middle and low prone areas of landslides.(4)Landslide prevention and control in Xiuning County: build drainage works and protective walls,increase forest ecological green protection,prohibit unreasonable human exploitation and utilization behavior,strengthen the ability and means of geological disaster monitoring,and improve the residents' awareness and ability for disaster prevention and mitigation;In the prone and low-prone areas of landslides,prevention should be given priority and control should be supplemented.