Evaluation Of Ecological Geological Environment Quality In Yanyuan County Based On GIS Technology

Yanyuan county is located in the southwest of liangshan yi autonomous prefecture,sichuan province,in the transition of the sichuan basin and the qinghai-tibet plateau region,belongs to the fold mountain landscape,regional rainfall is rich,the frequent landslides,mud-rock flow,ground subsidence in the area of geological disasters,fragile ecological environment,ecological and geological environment quality evaluation of yanyuan,can be in in order to establish the reasonable environmental protection yanyuan,industry layout and other strategies to provide scientific basis.Through field survey and data collection,this paper analyzes the yanyuan ecological and geological environment,including topography,climate characteristics,hydrological characteristics,stratum lithology,geological disasters and geological structure etc.,and according to the relevant ecological geological environmental quality evaluation index system of construction principles,and establish the evaluation system,and then select the corresponding evaluation index,and yanyuan county of ecological and geological environment quality comprehensive evaluation,this paper has carried out the following work:(1)According to the analytic hierarchy process(ahp)to the target object is divided into a target layer,criterion layer and three layer 12 indicators,according to the principle of evaluation index system building,selected the geological conditions,geographical condition and ecological condition as the three level indicators and select 12 secondary indicators,yanyuan ecological geological environmental quality evaluation system is established.(2)Of yanyuan stratigraphic lithology,fault zone,weather,hydrology,topography,soil,vegetation and other natural geographical environment and geological environment data is analyzed,using GIS technology to extract the yanyuan of engineering geology,fault density,height,slope slope to,irregular topography,precipitation temperature,drainage density,vegetation index and other information.(3)Will be extracted to ecological geological environmental quality evaluation index of the corresponding classification,using ArcGIS platform for comprehensive weighted each layer,and using the method of analytic hierarchy process to the corresponding index weight calculation,and then according to the distribution characteristics of composite layer statistics,yanyuan's ecological and geological environment quality with natural discontinuous method is divided into good,good,medium,four poor grades,and characteristics of various partition are analyzed in detail.