南方丘陵区生态水资源库脆弱度评价--以湖南省为例

Assessment of vulnerability of ecological water resource bank in hilly-land regions,South China: a case study of Hunan Province

以南方生态水资源库为研究对象,提出生态水资源库脆弱性概念,分析了其脆弱性成因和主要表现。从脆弱性成因角度构建了包含10个具体指标的南方丘陵区生态水资源库脆弱性评价指标体系。以湖南为研究案例,运用模糊物元评价模型对85个县级评价单元的生态水资源库脆弱度进行综合评判。结果表明,全省生态水资源库脆弱性等级以中等脆弱为主,其中,微脆弱等级3个,占总评价单元的3.5%,中等脆弱等级70个,占总评价单元的82.4%,强脆弱12个,占总评价单元的14.1%。脆弱度空间分布存在"西部大于东部,南部大于北部"的总体分布态势。其中,以湘西北、湘西南和湘南所构成的外部环形地带和以长沙、衡邵盆地为中心的中东部地带为全省两个比较明显的高脆弱区(带)。

A new concept of vulnerability on ecological water resource bank was provided to analyze the formation and representation of vulnerability of water resource system, by investigating ecological water resource bank in the hilly-land regions in south China. On the basis of formation of vulnerability, the evaluation index system on vulnerability of water resource bank, including 10 concrete indices , was also constructed in the hilly-land regions in south China. The ten indices included precipitation, surface water subsystem, soil water subsystem, vegetable water subsystem and economic subsystem,then the evaluation index system of vulnerability of ecological water resource bank in Hunan Province was established using analytic hierarchy process （AHP）. The vulnerability indices of ecological water resource bank were calculated in 85 counties of Hunan Province using fuzzy matter-element analysis method, Three grades （high, medium and low） were used in the evaluation index system. The main findings were： （1） Most counties showed medium vulnerability. The low, medium and high vulnerabilities accounted for 3.5% , 82.4% and 14.1% in the 85 counties, respectively. （2） The spatial distribution pattern was that the vulnerability in the west （or south） regions was higher than that in the east （or north） regions. Two significantly higher vulnerability zones included the external arc zone formed by northwest, southwest and south Hunan Province, and central-east zone centralized by Changsha, Hengshao Basin.