额济纳天然绿洲景观健康评价

Landscape health assessment on Ejin natural oasis.

在景观尺度上开展健康评价研究,不但可提供一个将自然生态过程与社会经济价值进行综合研究的基础,而且景观健康概念本身蕴含着在针对资源与环境问题开展研究时更为合适的时间和空间尺度.额济纳天然绿洲位于我国西北干旱内陆河黑河流域下游.近年来,随着黑河中、上游地区下泄地表径流量的减少,绿洲景观退化严重.基于研究区近十几年来的景观演变特征,分别从景观变化指标、生物物理指标、生态环境指标以及社会经济指标4个方面发展并构建了景观健康评价指标体系,制定了评价标准,并分别赋予了各指标相应的权重值,运用综合评判方法,得到了具有动态性、定量性的绿洲景观健康评价结果.结果表明,研究区景观近10多年来总体的景观健康指数为0.3042,健康等级紧邻“濒危的”级别.该结果较为客观、真实地反映了当前额济纳天然绿洲景观的健康状况,说明近10多年来研究区的景观健康状况与较早时期相比趋于恶化,发展态势表现出严重的不可持续性.

Landscape scale ecosystem health research could not only provide a basis for integrating natural ecological processes and social economic values,but also provide an appreciated temporal and spatial scale in dealing with the issues of resources and environment.The Ejin natural oasis landscape is at the lower reach of Heihe river basin in the arid inland regions of northwestern China.Owing to the lack of sufficient water resource from the upper reaches of Heihe River,a series of ecological and environmental problems are getting more serious in the oasis in recent years.Based on the past decade landscape change of the Ejin natural oasis,this paper developed a landscape health indicators system including landscape change indicators,bio-physical indicators,eco-environmental indicators and social-economic indicators,and established the criteria and weightiness for assessment indicators.The landscape health index (LHI) was finally figured out as 0.3042 by using fuzzy comprehensive evaluation method,which showed that the health condition of Ejin natural oasis landscape was ranked to 'severely ill level' in the landscape health assessment criteria system.The landscape health of Ejin natural oasis landscape today is much worse than in the past years,with a badly unsustainable developing trend.