塔克拉玛干沙漠南缘绿洲外围的天然植被

The Vegetation and Its Utilization in the Southern Fringe of the Taklimakan Desert

塔克拉玛干沙漠南缘是一片极端于旱的荒漠，生态环境严酷、脆弱；植物区系组成贫乏。根据植被生存所需要的水分来源，本文将绿洲外围的天然植被粗略地划分为雨育植物群落、毛管水植物群落，以及主要靠大气降水、地表散（径）流渗透和土壤包气带中的水汽维持生存的兼性植物群落，主要靠大气降水并从沙层中吸收凝结水维持生命活动的兼性植物群落；上述各类天然植物群落是保护绿洲支持系统的有机组成，使绿洲免于或减轻风沙流入侵。然而，植被现状令人忧虑，局部地段已构成严重的生态危机，急需加大对绿洲外围天然植被保护和恢复的力度，在确保最大限度地发挥生态效益的前提下进行适度利用。

The southern fringe of the Taklimakan Desert is the extremely arid desert.The ecological environment is bad and it is poor in flora composition. According to the watersources,this paper cIassified the natural vegetations into four plant communities. The com-munities are important for protecting the desert oasis. But the present situation is very bad,iturgently needs the further protection of the natural vegetation.