基于PSR-AHP模型的稀土矿区生态安全评价

Ecological Security Assessment in Rare Earth Mining Area Based on PSR-AHP Model

稀土开采导致矿区植被破坏、水土流失、土壤沙化等生态问题,为定量评估稀土矿区的生态安全状况,以Landsat系列数据作为数据源,以定南县岭北稀土矿区为例,结合压力-状态-响应(PSR)框架模型和层次分析法(AHP),构建了3个层次、10个评价因子的稀土矿区生态安全评价指标体系及评价模型。结果表明:林地对于矿区生态安全贡献度最大;矿区生态安全平均值由2008年的6.99增加为2014年的7.00,矿区生态安全总体上表现较为稳定,矿区植被的自然生长与复垦能改善生态安全状况,而对植被的人为破坏以及稀土开采活动会导致矿区生态安全恶化;生态安全等级为"极不安全"的区域面积减少了9.7%,高分影像上稀土开采区域A,B,C与其对应位置上也出现了空间分布和面积一致性的变化,矿点稀土的开采会直接导致其生态安全恶化。

The vegetation destruction,soil erosion,soil desertification and other ecological problems were caused by earth rare mining activities.To quantitatively evaluate the ecological security status of the Rare Earth（RE）mining area,we took Lingbei RE mining area in Dingnan County as study area using the PSR（Pressure-State-Response） model and the method of AHP（Analytic Hierarchy Process） to constructed its land ecological security assessment system and grade scale which was made up of 3 levels and 10 evaluation factors by selecting Landsat series imageries as data source.The results showed that the forest land had the largest contribution to the ecological security in the RE mining area;the average value of the ecological security in the RE mining area increased from 6.99 in 2008 to 7 in 2014,and ecological security in RE mining area was relatively stable as a whole.The natural growth and reclamation of the vegetation in the RE mining area improved the ecological security,but man-made destruction of vegetation and the RE exploitation worsen;the area of severe ecological security was decreased by 9.7%.There were consistent change in spatial distribution and area between RE mining region A,B,C in high resolution imageries and corresponding positions of severe ecological security.Mining RE ore directly led to the deterioration of the ecological security.