Abstract: For the sake of improving the eco-environment, and preventing degradation of the vegetation, the water transport project in the lower Tarim River was carried out in April 2000. According to the water path, temporal and spatial distributions of water resources in this region were greatly changed in the past 10 years. As a result, the eco-environment condition has also changed obviously. In this paper, field surveys data and remote sensing data from 2001 to 2011 were used to analyze the variation of groundwater level and natural vegetation; and the vegetation response to the groundwater level variation in typical sections were also discussed. The results indicated that (1) the fluctuation of groundwater level in each section is closely related to the quantity and duration of the water transport, and shows a process from a significant rise to slow reduction, and to a slight rise during the 10 years; the correlation coefficient of groundwater depth variation and water transfer quantity is approximately 0.78, and the correlation coefficient of groundwater depth variation and water transport duration is 0.7. (2) The area of vegetation cover in this region showed an increasing trend from 2001 to 2011, and the biggest area change in natural vegetation occurred in shrub land; the fraction of vegetation coverage were increased obviously during 2001-2006, and changed slightly from 2006 to 2011. (3) The fraction of vegetation coverage was found to increase along with the rise of groundwater level. In vertical direction of the river, ground water level and vegetation coverage showed a similar spatial distribution: the more distance away from river the lower groundwater level is, the lower fraction vegetation coverage. In parallel direction of the river, the response intensity of the fraction of vegetation coverage to groundwater level showed a decreasing trend along the distance from Daxihaizi reservoir.

Key words: eco-environment, lower Tarim River, remote sensing, intermittent water transport