Study on the Characteristics of Water Conversion after Conveying Stream Water to the Lower Reaches of the Tarim River for Regenerating the Ecology

Located in the north Tarim Basin,the Tarim River is the longest continental river in China.However,stream flow at the lower reaches(357 km in length) of the river had been cut off since 1972.In this paper,the characteristics of leakage during stream water conveyance are analyzed based on the monitoring data collected during 6 times of conveying stream water to the lower reaches of the Tarim River for regenerating the ecology.The results show that the stream water leakage is related to the hydrological and geological conditions and the time of stream water conveyance.Moreover,the conversion trend of stream water to groundwater under the long-term stream water conveyance is simulated using Processing Modflow.The results reveal that the conversion efficiency of stream water to groundwater is gradually reduced under such intermittent stream water conveyance,but the evapotranspiration of groundwater is gradually increased,and a dynamical stability of groundwater level will be attained.Temporally,the groundwater level is continuously increased with the time of stream water conveyance.Viewing from the spatial distribution of groundwater level,the dynamical stability of groundwater level is advantageous for regenerating the vegetation along both riversides of the lower reaches of the Tarim River.