西北干旱荒漠生态区脆弱性动态监测及驱动因子定量分析

Dynamic Monitoring of Ecological Vulnerability in Arid Desert Ecological Region of Northwest China and the Quantitative Analysis of Its Driving Forces

全球气候变化和人类活动双重胁迫下,西北干旱荒漠生态区的脆弱生态系统发生了深刻变化。论文在充分考虑研究区生态环境背景特征(沙漠化、盐渍化、风力侵蚀、干旱等灾害严重)的基础上,引入极端气候灾害因子(指示气候变化)和大尺度景观格局指数(指示人类活动对生态景观的干扰),构建了西北干旱荒漠生态区的生态脆弱性评价体系,并对研究区2000—2013年的生态脆弱性时空变化格局及其驱动机制进行了定量分析和讨论。研究结果表明:西北干旱荒漠生态区的生态脆弱性总体上处于中-重度脆弱状态;其生态脆弱性空间分布格局总体上呈现自东向西递减的趋势,西部局部地区则呈现"E"字型格局,该分布格局主要受西北内陆地区大气环流以及三山夹两盆的特殊地貌影响;2000—2013年,西北干旱荒漠生态区生态脆弱性呈现减小趋势,其生态脆弱性变化状况受气温、降水以及人类活动影响显著。研究成果可以为西北干旱荒漠生态区的生态保护和治理提供决策支持。

Under the double stress of global climate change and human activities, the fragile ecosystem in arid desert region of Northwest China has undergone profound changes. Thus,how to evaluate the ecological vulnerability of the arid land has become a hot topic in the field of ecology. Fully considering the characteristics of the eco-environment（desertification,salinization, wind erosion, drought and other disasters） in the study area, we introduced extreme climate event factors（indicating the climate changes） and large-scale landscape pattern indexes（indicating the disturbance of human activities on the ecological landscape） to establish the evaluation system of ecological vulnerability in arid desert region of Northwest China.Then, the spatial-temporal change of ecological vulnerability and its driving mechanism during the past 13 years were analyzed and discussed. The results showed that： the ecological vulnerability of arid desert region in Northwest China generally belonged to the level of moderate or severe vulnerability, and the spatial distribution pattern of ecological vulnerability showed a decreasing trend from east to west and a＂E＂pattern appeared in the western part,which was significantly affected by the atmospheric circulation and special landform of＂Two basins sandwiched with three mountains＂. During the period of 2000-2013, the ecological vulnerability in the arid desert region of Northwest China showed a decreasing trend, and the changes were greatly affected by temperature, precipitation and human activities. There were significant relationships between the change intensity of ecological vulnerability and climatic tendencies of precipitation and temperature. The research results can provide decision supports for ecological protection and management in arid desert region of Northwest China.