生态输水后塔里木河下游地下水的动态变化

以生态建设和环境保护为根本的塔里木河下游生态输水工程,在实施近3年中,有10.15×10⁸m^3/生态水分5次流向塔里木河下游地区.随着生态水流的到来,该地区生态环境发生了明显的变化,直接反映在输水河道周围地下水的动态变化以及下游植被的响应上.根据近3年在塔里木河下游对地下水的动态监测,就生态输水后地下水位的变化规律进行了初步分析.结果显示,输水后地下水位表现出明显的时空动态变化规律.从时间上看,距河道远近不同的地下水位升降规律各异;从空间变化看,地下水位表现出以输水河道为中轴向外变化逐渐减弱和输水后不同地区地下水位抬升幅度的差异;鉴于地下水在达到一定水位以后其变化明显趋向复杂,而不同植被生长所要求的水位不同.因此,确定输水后的最佳生态水位将对今后在塔里木河下游进行大规模恢复和重建工作具有重大意义.

Dynamic change of groundwater after ecological water transport at the lower reaches of Tarim River

The ecological water transport project taking the ecological construction and environmental protection as fundamental task, has been carried out about 3 years at the lower reaches of Tarim River. There is 10.15?08 m3 ecological water flowing into this region for five times; and the eco-environment also changes obviously with the ecological water coming, reflecting directly in the dynamic change of groundwater around the transport river and the response of vegetation at the lower reaches of the river. According to the dynamic monitoring on the groundwater in recent 3 years, the change rule of the groundwater level after the transport was analyzed preliminarily. The groundwater level appears marked spatiotemporal dynamic change rule after the transport. In view of time, the groundwater levels in different distance from the river have different rising and falling rule. From viewpoint of space change, the groundwater level changes outward becoming smaller gradually with the transport river as center; and its rising range varies in different area. In view of that the groundwater change tends to be complex after the groundwater reaches definite level, and different vegetation growth needs different water level, confirmation of the best ecological water level after ecological water transport possesses accordingly important significance to restoring and rebuilding work at the lower reaches of Tarim River in future.