Abstract:

Abandoned quarries seriously destroy ecoenvironment and affect social and economic sustainable development.How to measure ecoenvironmental impact of abandoned quarries,which has become a problem,is what this paper is aimed to solve.GIS was taken as working platform.Firstly,based on the survey data of abandoned quarries geological environment and the theories of the relationship system between human beings and ecoenvironment,ecoenvironmental impact evaluation model of abandoned quarries was built from two perspectives of ecoenvironmental damage and surrounding area sensitivity.Secondly,the evaluation index system of ecoenvironmental damage of abandoned quarries,including land occupation area,rock slope angle, the volume of solid waste,the ratio of stonepit area to land occupation area,the depth of stonepit and the possibility of geological disaster,was established according to the principles of representativeness and availability.Index weights were determined using means of Analysis Hierarchy Process and value assignment standard was given on the basis of previous research and expert knowledge.Then the degree value of ecoenvironmental damage was calculated using means of Comprehensive Evaluation Model.Thirdly,residential areas, roads, railways, rivers and scenic areas were selected as sensitive elements,and the sensitivity of sensitive elements was determined by means of Analysis Hierarchy Process.The spatial distance between abandoned quarries and the nearest sensitive elements was measured using method of GISbased Spatial Analysis.Based on Distancedecay Law and Gravity Model,the distance adjustment coefficient was computed,which was used to adjust the sensitivity of sensitive elements.Combined the above five sensitive elements,the degree value of surrounding area sensitivity was calculated.Fourthly,according to the definition,the degree value of ecoenvironmental impact of abandoned quarries was obtained using the degree value of ecoenvironmental damage and the degree value of surrounding area sensitivity.Ecoenvironmental impact degree matrix,which was used to classify the degree value of ecoenvironmental impact of abandoned quarries,was established by referring to risk matrix method.The degree value of ecoenvironmental impact of abandoned quarries was divided into five degree levels: high, slightly high,average,slightly low,low.Finally,a case study including 205 abandoned quarries was conducted in Tongshan District of Xuzhou city.The results showed that the percentage of high,slightly high,average,slightly low,low degree levels of ecoenvironmental impact of abandoned quarries were 20%,307%,507%,122% and 44% respectively,and the four abandoned quarries of high degree level of ecoenvironmental impact were Heqiu,Yuezhuang,Sheng Shiwei,Quan Taiyin.Abandoned quarries of the high degree level of ecoenvironmental impact were mostly in Liuquan,Maocun,Liguo,and abandoned quarries in the north part of Tongshan District needed ecoenvironmental construction more urgently than those in south part.This paper was supposed to provide a scientific method to evaluate ecoenvironmental impact of abandoned quarries and choose abandoned quarries that sorely needed ecoenvironmental construction