Ten questions and visions of groundwater in the Taklimakan Desert: Based on 60−year hydrogeological investigation and research

This paper is the result of hydrogeological survey engineering.

Objective A systematic review has been conducted on groundwater investigation and research in the Taklimakan Desert over the past 60 years to consolidate significant achievements and insights regarding groundwater recharge, discharge, and circulation. The review highlights key deficiencies in current research efforts, presents ten unresolved questions, and identifies areas for future study.

Methods Investigation reports and academic papers were meticulously gathered on groundwater in the Taklimakan Desert for a comprehensive review on groundwater quality, quantity, and circulation. This review was conducted in conjunction with the latest relevant findings on desert groundwater from both domestic and international hydrogeological communities.

Results Groundwater in the desert primarily originates from lateral groundwater flow from oases, precipitation, and river water infiltration. It is predominantly consumed by evapotranspiration, with a limited amount withdrawn by humans. The vast groundwater storage in the region is estimated to be around 80 trillion m³. However, there is currently significant uncertainty in estimating groundwater recharge and discharge. The overall groundwater quality is generally poor, as evidenced by the spatial distribution of total dissolved solids (TDS), with most of the desert containing saline groundwater with TDS levels ranging from 5 to 10 g/L, while only a small area has TDS levels below 5 g/L. Vertically, the groundwater quality is characterized by saline groundwater in deeper layers and brackish groundwater in upper layers. Regionally, groundwater flows northward and then shifts eastward at the northern edge of the Tarim River fluvial plain, with an average velocity of 55.94 m/a.

Conclusions To address these scientific questions, future studies should focus on quantifying groundwater recharge and discharge using more precise and extended methodologies. Detailed data on groundwater circulation can be obtained through packer tests and monitoring to systematically analyze circulation patterns, establish regional groundwater flow patterns, and quantitatively summarize the characteristics of each flow system. Additionally, efforts should be made to identify sources of fresh water and develop techniques for utilizing high Total Dissolved Solids (TDS) groundwater in the desert in upcoming investigations and research endeavors.