干旱区内陆河流域生态脆弱性评价——以新疆塔里木河流域为例

生态脆弱性是景观或生态系统在特定时空尺度上相对于干扰而具有的敏感反应和恢复状态 ,它是生态系统固有属性在干扰作用下的表现6] 。关于生态脆弱性的研究 ,可追溯到 2 0世纪初 ,美国生态学家 Clements提出了生态过渡带 ,自 80年代以来 ,该领域成为生态学研究的一个热点。干旱内陆河流域气候条件 ,尤其是水热条件和地貌特征 ,是植被生态、土壤环境及水环境形成与分异最主要的控制性因素 ,几大环境要素之间相互联系 ,相互制约 ,形成内陆河流域生态环境空间分布规律和生态系统功能在空间不同地带上的差异性 2 ] ,并表现出不同程度的脆弱性…

Ecological Fragility Assessment on Continental River Basin in Arid Zone--Taking Tarim River Basin, Xinjiang as An Example

Great changes of ecological environment have taken place in Tarim River Basin of continental river basin in arid zone since last 5 decades.As a result, a series of characteristics that are not stability appeared.With regard to the natural conditions and artificial interference, 20 complex factors of water resource system, land source system, vegetation resource system and environment system (esp.desertification state) are chosen to analyze the ecological fragility.Through establishment of indicator system of ecological fragility assessment and classification standard, based on the arithmetic logarithm processing, ecological fragility index (EFI) is built up.The results are as follows: the EFI values of source stream area including Aksu River Basin, Yerkant River Basin, Hetian River Basin and main stream including upper reaches, middle reaches and lower reaches of Tarim River Basin are 0.08, 0.23, 0.32, 0.25, 0.53 and 0.87 respectively.The degrees of ecological fragility belong to slight fragility, medium fragility and extreme fragility in Aksu River Basin, middle and lower reaches of Tarim River respectively in addition to general fragility in other three sections.