气候变化下青海湖流域生态健康评价研究

Study on ecological health evaluation of Qinghai Lake Basin under climate change

全球变化与人类活动对陆地生态系统产生了深远的影响,对气候变化表现极其敏感的青海湖流域在此过程中系统内、外环境及生态健康状况均发生了一定变化。相关研究表明,近50年流域气候环境暖湿化程度不断加深,2004年以来青海湖流域降水显著增多。基于此,以青海湖流域为研究对象,从流域内、外部环境特征两方面出发选取共10个指标构建生态健康评价指标体系,采用AHP及专家打分法确定指标权重,将各指标图层叠加得出流域2000年、2005年和2010年生态健康状况图,用以探讨流域生态健康状况及变化趋势,结果表明:(1)暖湿期以来流域内部环境指标改善明显,其中年降水量、NDVI及NPP指数显著增长,但随着社会经济发展外部环境带来的压力也在逐步增大;(2)流域三期生态健康状况均以不健康、亚健康及健康状态为主且空间上健康等级均大致由东—西逐渐递减;(3)2000—2010年生态健康综合指数由0.542上升至0.547,生态健康变化稳定呈上升趋势,流域中西部、东南部地区生态健康状况改善明显,而东部及西南部局部地区有所恶化。气候变化对青海湖流域生态健康状况产生了一定影响,了解这一变化过程对青海湖流域生态环境规划管理与健康可持续发展具有重要的科学和现实意义。

Global changes and human activities have a profound impact on the terrestrial ecosystem.The Qinghai Lake Basin,which is extremely sensitive to climate change,has undergone certain changes in the internal and external environment and ecological health of the system.Related research shows that the degree of warming and humidification of the climate environment in the basin has been deepening in the past 50 years,and the precipitation in the Qinghai Lake basin has increased significantly since 2004.Based on this,taking the Qinghai Lake basin as the research object,a total of 10 indicators are selected from both the internal and external environmental characteristics of the basin to construct an ecological health evaluation index system,and the AHP and expert scoring method are used to determine the index weight,and each index layer is superimposed.The ecological health status maps of the basin in 2000,2005 and 2010 were used to explore the ecological health status and change trends of the basin.The results showed that:(1)The internal environmental indicators of the basin have improved significantly since the warm and humid period,including annual precipitation,NDVI and the NPP index has increased significantly,but with the social and economic development,the pressure brought by the external environment is gradually increasing.(2)The three stages of ecological health in the basin are mainly unhealthy,sub-healthy and healthy,and the spatial health level is roughly.It gradually decreases from east to west.(3)The comprehensive ecological health index rose from 0.542 to 0.547 from 2000 to 2010,and the ecological health changed steadily and showed an upward trend.The ecological health of the central,western and southeastern parts of the basin improved significantly,while the eastern and southwestern parts have deteriorated.Climate change has had a certain impact on the ecological health of the Qinghai Lake Basin.Understanding this change process has important scientific and practical significance for the ecological environment planning and management and healthy and sustainable development of the Qinghai Lake Basin.