Abstract: Taking Yingsu-section in the lower reaches of Tarim River, Xinjiang, China, as the study area, using the methods of qualitative and quantitative analysis, the study considered different water conveyance conditions from the year of 2000 to 2015(zero water conveyance of 2008, including water conveyance pole juvenile of 2009, and more water conveyance of 2011), in order to investigate the relation between ecological water conveyance and the change process of groundwater table, and find the dynamic response laws of the groundwater table in the area. As the source of water conveyance, changes of the level of Bosten Lake directly affect the ecological water conveyance quantity. From 2000 to 2015, there have been sixteen water cycles and more than 20 stages of ecological water conveyance process in the lower reaches of the Tarim River, the cumulative water conveyance quantity was about 51.12×10⁸ m³, the total days of water supply was about 1 577. During the period, the level changes and the trend of ecological water conveyance were basically the same, showing a positive correlation. From 2000 to 2015, the groundwater table of Yingsu-section presented wave-type increase or decrease, and the overall trend was consistent with the ecological water conveyance. The deepest groundwater table was in 2009 and the highest groundwater table was in 2011, because 2011 was the year with the most water supply, but the ecological water conveyance in 2007-2009 was insufficient. The results indicate as follows:(1)The groundwater table overall showed a steady decline trend, but there was significant increase trend in individual months during a year, which mainly concentrated in the water conveyance time. In addition, there was also a certain increase of groundwater table during February to March due to the permafrost melting.(2)The response of groundwater table changes to ecological water conveyance showed obvious time synchronization near the river, especially within 60 meters away from the river, but there was a lag in the response time of the groundwater table which far away from the river.(3)With the increase of the distance to the river, the groundwater level exhibited a linear decreasing trend, the depth level was related to the ecological water conveyance and the lag time of each year. Owing to the ecological water conveyance, groundwater table maintained gradually at 2-6 meters within 750 meters away from the river. It is a reasonable level of groundwater that required by the growth of plants in Yingsu-section. What's more, in order to obtain the maximum ecological benefit of ecological water transfer process, not only maintaining a certain amount of water transfer is necessary, but also maintaining the continuity of the water cycle is needed.

Key words: lower reaches of Tarim River, groundwater table, ecological water conveyance, Yingsu-section