塔里木河下游断流河道输水的生态变化分析

根据连续多年监测获得的塔里木河下游地下水位、植被数据,对比分析了塔里木河下游生态输水后地下水位、生物量、物种多样性的变化。结果表明:实施生态输水工程后,地下水位变化显著,地下水位逐渐抬升,下降趋势得以控制。草本植物生物量的变化趋势与每次输水量变化趋势基本一致,即随着输水量的增加草本植物的生物量也相应增加,输水的时间、输水量的多少对草本植物生物量有较强影响。地下水位埋深上升,物种多样性也呈上升趋势,但二者并不同步,物种多样性上升趋势滞后于地下水位的上升,这表明地下水位的抬升有利于植物多样性的增加,但是地下水位变化对植物多样性的影响是一个渐变的过程。

Ecological Changes of Water Conveyance in Dried-up Riverway in the Down Stream of Tarim River

The paper compares and analyzes the variations of groundwater level, biomass and species diversity in the downstream of Tarim River after water conveyance based on the long-period and continuous monitored datas of groundwater level and vegetation in the region. The outcomes show that the groundwater level increases gradually and the downward trend have been controlled after the project of ecological water conveyance. The variation trend of biomass of herbs is basically the same as that of water conveyance, i.e. the biomass of herbs increases accordingly along with the increase of water conveyance and the time and the amount of water conveyance have greater influence to the biomass of herbs. The depth of groundwater level increases and the species diversity also shows the trend of increase, but they are not synchronous. The increase trend of species diversity lags behind the increase of groundwater level, showing the increase of groundwater level is beneficial to the increase of diversity of plants, but the influence of variation of groundwater level to the diversity of plants is a process of gradual change.