干旱区生态环境知识资源中心

Understanding the dominant causes of streamflow alteration and effects of the current water diversion scheme is beneficial for sustainable management of water resources in an arid area. This study presents a quantitative attribution of the run-off changes between headstreams and mainstream from 1960 to 2015 using the Choudhury-Yang equation and evaluates the effects of 18 times of ecological water conveyance in the lower reaches of the Tarim River Basin (TRB). Our results suggest that climate change was the primary determinant of increase of the streamflow in the headstreams from 2000 to 2015. While in the mainstream, human activities played a dominant role in deduction in the streamflow with the contribution of 54.8-355.6%. Eighteen episodes of ecological water conveyance have a positive effect on rising groundwater level and are highly related to seed falling time of Shrub and Perennial herbaceous and Annual herbaceous except for Arbor. It indicates that restoring the long-term drying of the lower reaches through continuous water conveyance is feasible, although the existing programme has not restored the entire riparian system. Our study suggests that it is necessary to adopt an integrated approach for water resources allocation rather than relying on a single tributary contribution in the TRB.