准噶尔盆地生态环境时空演化及生态环境问题分析

分析了准噶尔盆地的地域概况,指出其地处我国西北干旱区,表生生态环境脆弱的特征。以地下水与生态环境之间的关系为依据,结合自然地理条件对准噶尔盆地生态系统类型进行划分,探讨了1990、2000和2009年3个时期准噶尔盆地生态环境时空演化过程;结合准噶尔盆地水资源的开发利用状况和生态环境演化规律,分析了生态环境变化引起的主要生态环境问题,并集中论述了以下几点：①山地生态系统中永久性冰川雪地面积减少,河流径流量呈增加趋势,山地生态系统的水资源涵养能力下降;②地下水位下降,溢出带北移;③湖面萎缩;④天然植被退化;⑤耕地和建设用地面积扩展;⑥盐渍化耕地面积增加,盐渍化总面积在1990～2000年呈增加趋势,而在2000～2009年间基本不变,说明传统的农业灌溉方式对水资源的利用产生了重要的影响,导致了盐渍化面积的变迁。

Space-Time Evolution and Problems of Ecological Environment of Junggar Basin

Geological conditions of Junggar Basin are analyzed in this study,it is located in the northwest arid areas of China with a vulnerable supergene eco-environment.Based on the relationship between underground water and ecological environment,natural geological conditions are combined to classify ecosystem types in the study area,space-time evolution of its eco-environment in three periods is discussed:1990,2000 and 2009;development and utilization of water resources in Junggar Basin as well as its eco-environment evolution laws are taken to analyze problems brought by eco-environment changes,focusing on the following points:A.decreasing area of permanent glacier in mountainous ecosystem,increasing volume of river runoff,reducing capacity of mountainous ecosystem in conserving water resources;B.decreasing underground water,overflowing belt shifting northwards;C.shrinking lake area;D.degrading natural vegetation;E.expanding area of cultivated land and construction land;F.more cultivated land influenced by salinization,showing an increase trend between 1990 and 2000,maintaining stable between 2000 and 2009,which implies that traditional agricultural irrigation method has brought significant influence on the utilization of water resources,and resulted in the shifting area of salinized land.