晋北地区生态环境脆弱性的GIS综合评价

生态环境脆弱性评估可以为退化系统的综合整治提供策略依据。晋北地区作为我国北方农牧交错带的组成部分,在自然和人为因素的综合作用下,表现出脆弱性的特征。本文利用空间主成分分析和层次分析法,结合遥感数据和地理信息系统技术,评价了晋北地区生态环境的脆弱性。结果表明:在自然和人为因素综合作用下,晋北地区生态环境脆弱性呈现不平衡的空间分布特征,东北部重,西南部轻。极度和重度脆弱区主要分布在东北部,占整个研究区面积的33.1%;微度和中度脆弱区主要分布在西南部,占41.9%;轻度脆弱区在整个研究区几乎均有分布,占24.9%。轻度和中度脆弱区占整个研究区面积的55.5%。总体来看,晋北地区大部分区域处于中度和轻度脆弱性水平。自然因素是晋北地区生态环境脆弱性的主导因素,人为因素是其脆弱性变化的关键外在因素。影响晋北地区生态环境脆弱性的自然因素主要有干旱、NDVI、水土流失比率;人为因素主要有土地利用、第二产业占GDP比重、环保投资指数、水资源量。研究结果为晋北地区合理调控人类活动,保护和治理生态环境提供一定的依据。

Integrated Assessment of Eco-environmental Vulnerability in North Shanxi Province

Assessment of eco-environmental vulnerability can be taken as a strategic basis for the comprehensive improvement on a degraded system. North Shanxi Province was a constituent part of farming-pastoral ecotone in north China, was characteristic of vulnerable under integrated impact of natural and human factors. In this paper, based on remote sensing data and geographic information system software, combined with spatial principal com- ponent analysis and analytic hierarchy process （AHP）, an integrated method was used to evaluate the eco-envi- ronmental vulnerability of North Shanxi Province. The results show that the vulnerability of the eco-environment in North Shanxi Province is characteristic of imbalance in general under integrated influences of natural and hu- man factors. The northeast part is evaluated as the most vulnerable region, which occupy 33.1% of the total stud- ied area. The southwest part is the slightly and moderately vulnerable areas, which occupy 49.1% of the total studied area. And the lightly vulnerable areas scatter throughout the entire region. Totally, the moderately and lightly vulnerable areas occupy 55.5%. This indicates that a majority of the region owns moderate and light vul- nerability. The vulnerability in this area is mainly caused by nature factors, and human activities are the critical external reasons to cause the variable of vulnerability degree. The natural factors affecting the eco-environmental vulnerability of the North Shanxi Province are aridity, normalized difference vegetation index （NDVI）, water and soil erosion rate, etc., whereas the human factors are land use, proportion of the second industry accounting for GDP, index of environmental protection investment and water source amounts, etc. The main characteristics of the extremely and heavily vulnerable regions are aridity, low NDVI, serious water and soil erosion, unreasonable land use, high proportion of the second industry accounting for GDP, low environment protection investment in- dex and few water source amounts. Degree of eco-environmental vulnerability in North Shanxi Province will drop with increasingly rational human activities and more and more environmental protection investments. Re- suits of this research can provide a basis for rational regulating and controlling of human activities and eco-envi- ronment protection and improvement in North Shanxi Province.