环渤海五省市生态风险评价

生态风险评价是近20年来兴起的一个研究热点,是地理学、生态学、环境风险评价等领域的综合交叉点。对生态风险进行研究,有助于了解研究区内的生态环境状况,从而降低生态风险,改善人地关系。环渤海地区是人地矛盾非常突出的典型区域。本文参考美国环保署(USEPA)的框架,根据相对风险评价模型的分级排序思想,评估环渤海五省市的单项及综合生态风险值。采用生态资产表征生态终点,进行风险受体的损失度量;通过构建评价指标体系,采用主成分分析和ArcGIS加权叠加的方法,进行受体环境的脆弱性评价;基于土地利用和植被斑块数据,利用景观格局指数法评价生态系统的结构易损性。结果表明:海陆交错带、山地丘陵区和城市是典型的高生态风险区域;低风险区域主要分布在地形、水热、植被状况好、灾害频次低的平原和部分丘陵地区。对于高风险的区域,做好风险防范至关重要。

Ecological risk assessment of five provinces around the Bohai Sea

Ecological risk assessment is a hotspot arising in recent 20 years,being an integrated junction of geography,ecology,and environment risk evaluation.The study of ecological risk is helpful for understanding local ecological environment,reducing ecological risk,and finally improving the interactions between human beings and nature.Taking the Bohai rim,a typical region of sharp contradiction between population and land,as a case,this paper assessed the ecological risk of five provinces(municipalities) around the Bohai Sea by referring to USEPA framework of ecological risk and combining the methodologies of grading and ordering in relative risk method.Different materials and methods were applied in different steps of the assessment framework.For risk receptor analysis,the ecological endpoints were expressed in ecological capital loss,while the environmental vulnerability was calculated by principal component analysis and weighted layer stack methods according to the index system.Then,the structure vulnerability was evaluated by landscape index approach based on land use data and vegetation patches data.In the study area,the typical regions with high integrated ecological risk were sea-land interaction belts,mountainous and hilly areas,and cities,while those with low ecological risk were mainly distributed in plains and some hills,where the topography was relatively gentle with low relief,water and heat conditions were favourable,vegetation was dense,and natural disasters frequency was relatively low.For the high risk areas,it would be critical for risk prevention.