基于沙漠化程度和NDVI指数的奈曼旗生态安全评价

Ecological security assessment of Naiman County based on desertification degree and NDVI index

从土地利用/覆被角度进行生态安全评价是土地资源可持续利用研究的核心和基础。在强调沙漠化过程影响的条件下,本文以乡镇为评价单元,以土地利用现状和对应的NDVI值为评价依据,将层次分析法(AHP)和综合评价指数法有机结合,对内蒙古奈曼旗地区的生态安全格局进行了综合评价。结果表明:从1985、1995和2005年3个分析年份的现状来看,奈曼旗的生态安全状况经历了极不安全-较安全-较安全、安全的临界状态的变化过程;安全区和较安全区域面积由零逐渐增加,到2005年二者区域面积之和占到了总面积的2/3之多;虽然局部地区如巴嘎波日和苏木出现恶化-好转-恶化的反弹趋势,但区域整体生态安全水平是好转的趋势。

Ecological security assessment from the viewpoint of land use/cover is the core and base of the study on sustainable land use. With the emphasis on the impacts of desertification process, a township scale comprehensive assessment was made on the ecological security pattern in Naiman County of Inner Mongolia, according to the present status of land use/cover and corresponding NDVI value, and by the combination of analytic hierarchy process （AHP） and integrative assessment index. The ecological security situation of the County had undergone extreme unsafety - more safety - critical state between more safety and safety in 1985, 1995, and 2005. The areas of safe and more safe increased gradually from zero, and their sum accounted for two thirds of the total. Although a few townships such as Bagaborihe had a rebound trend of deteriorated - improved - deteriorated, the overall situation of ecological security in the County was improved.