雅安芦山4.20震后县级单元生态系统风险评价

区域生态风险评价是对各种生态风险及环境问题进行评价和管理的重要手段。针对雅安地震灾区特殊的自然地理及生态环境特征,选取芦山县为研究对象,采用遥感、GIS及SPSS统计分析的方法,通过风险源、风险受体、暴露和易损性分析,建立生态风险综合评价模型,划分生态风险区类型,进而提出生态风险管理对策。结果表明:1)微度和低度生态风险区集中分布在高海拔的森林及草地生态系统,该区生物多样性丰富,抗干扰能力较强,地质灾害及人类活动影响较小;2)中度和高度生态风险区具有沿农田及建设用地生态系统集聚分布的特征,该区地质灾害频繁,地壳活动性较强,生态系统抵抗灾害的能力较差。研究结果可为地震灾区防御、规避风险及安全选址提供科学依据。

Risk Assessment of Ecology System in Unit at the County after Ya'an 4 .20 Earthquake

Regional ecological risk assessment is an important approach to evaluate and manage all kinds of ecological risks and envi -ronmental issues .Based on the special characters of natural geography and the ecological environment of Ya 'an earthquake -stricken area , this paper selected Lushan County as the research object , adopted the method of remote sensing , GIS and SPSS statistical analy-sis, then established ecological risk comprehensive assessment model by analyses of risk resource , risk receptor, exposure and vulner-ability, finally proposed ecological risk management strategies .The results are as following:1) the micro and low degree ecological risk were mainly distributed in the high altitude of the forest and grassland ecological system where the biodiversity is rich and the anti-jamming capability is strong , less influence of geological disasters and human activities .2) The moderate and high degree ecologi-cal risk area is concentrated distribution on the farmland and construction land ecosystem where frequent geological disasters and crus -tal activity is stronger , the poorer ability to fight disasters of the ecosystem .The results of the study can provide the earthquake zone defense, avoid risks and provide a scientific basis for safe location .