中文摘要：

对已干涸50多年的青土湖进行人工输水,引起区域植物群落变化,对干旱区植被恢复研究具有参考意义。经过4 a的定位观测,应用空间分布指数及典范对应分析方法,分析青土湖岸的植物群落结构及与其环境的关系,结果表明：在人工湖形成过程中,距水面0~100 m范围的地下水位上升至3.50 m以上,地下芽植物数量剧增,呈集群分布;50~200 m范围的植物种集群趋向均匀分布。青土湖输水是极端水干扰土壤水盐再分配,促成植物群落组成结构单一,是一种植物群落格局配置适应环境的变化。植物群落空间结构表现出随地下水位和土壤盐分的空间序列,不同生活型植物种的比例与其距水源距离相关,植物种变化影响植物群落空间结构。

英文摘要：

The artificial water conveyance to the Qingtu Lake dried up for more than 50 years bring about the change of local vegetation communities,and it is of referring significance for researching the vegetation regeneration in arid area. After carrying out a four-year locating observation,the relationship between the plant community structure and its environment at the Qingtu lakeshore was analyzed using the spatial distribution index and canonical correspondence analysis. The results showed that,during the process of artificial lake formation,the distribution of plant species was gradually dispersed and differentiated. The number of cryptophytes in the areas 0- 50 m from the water body was sharply increased,and the groundwater level in the areas 3. 50 m from the water body was raised to about 3. 50 m. The distribution of plant species was in clusters and trended to uniform in the areas 50- 200 m from the water body. The water conveyance to the Qingtu Lake promoted a simple structure of the plant communities,and it brought about a distribution pattern of plant communities to adapt environment change. The spatial structure of plant communities was changed with the change of groundwater depth and soil water-salt regime,and the change of plant species changed the spatial structure of plant communities.