应急输水干扰下塔里木河下游荒漠植被的变化

根据5年来在塔里木河下游的监测结果,结合实测数据和历史资料,对输水前后地下水位以及荒漠植被的变化进行对比分析.结果表明:随着应急输水工程的继续和扩大,离河道一定范围内地下水位升高明显.相应地,下游植被对输水干扰的生态响应也很显著,沿河岸及古河道附近多种草本植物又重新出现;随着生境的改善,一些耐旱乔、灌木长势也出现明显好转,主要表现在植被盖度的提高,种类的增加,胡杨冠幅、郁闭度和基部萌生枝的增加以及胡杨次生苗、实生苗的出现.

Effects of Emergency Water Transpotation on Desert Vegetation at the Lower Reaches of Tarim River

The present study was designed to analyze the change of ground water level and desert vegetation before and after water transpotation based on 5 years' monitoring results at the lower reaches of Tarim River.The resuts indicated that the ground water level went up significantly with continuous expansion of emergency water.Correspondingly,the ecological response of vegetation downstream was also very great,a lot of herbaceous vegetations along river bank restored.At the same time,some xerophytic arbor and bush grew better obviously with the habitat improving mainly judging from the increase of vegetation coverage,species richness,crown of P.euphratica,crown density and sprouting leaves from root as well as the emergence of the secondary seedlings and seedlings.