西北内陆河各流域地下水储量变化归因分析

Attribution analysis of groundwater storage variations across inland river basins in Northwest China

  • 摘要: 为揭示西北内陆河不同流域地下水储量变化特征及其影响因素差异,本文基于灌区与非灌区分区视角,对比分析2002—2020年内陆河各流域地下水储量的时空变化特征,利用水量平衡方程分离自然与人为因素影响并量化其贡献。结果表明:①内陆河流域整体地下水储量以0.29 cm/a的速率下降,呈“北降南升”的空间格局;灌区的下降速率(0.93 cm/a)约为流域的4倍,且在南北疆多数流域灌区降幅更为显著。②不同流域地下水储量变化的主要影响因素存在明显差异,但总体上与地表水、地下水供水量和人口密度显著相关。③而灌区主要受地下水开采、灌溉面积扩张及蒸散影响,降水和地表水补给对多数流域灌区地下水储量具有缓冲作用;地表水的大量取用是非灌区地下水储量减少的重要因素,在塔里木盆地、河西走廊等流域尤为显著。研究结果可为旱区地下水可持续利用与管理提供科学依据。

     

    Abstract: In this study, to reveal the variability in groundwater storage changes and their driving factors across different inland basins in Northwest China, we applied a comparative framework based on the partitioning of irrigated and non-irrigated regions. Groundwater storage anomaly (GWSA) from 2002 to 2020 was analyzed to characterize its spatiotemporal variations, and the impacts of natural and anthropogenic factors were separated using a water balance approach, with their respective contributions quantitatively assessed. Results show the following ①The overall GWSA decreased at a rate of 0.29 cm/a, exhibiting a spatial pattern of decreasing trends in the north and increasing trends in the south. The rate of decrease in irrigated regions (0.93 cm/a) was approximately four times greater than that in non-irrigated regions, with more pronounced depletion observed in irrigated regions across most basins in both northern and southern Xinjiang. ②The dominant factors of GWSA variations differ significantly among basins, but are generally associated with surface water supply, groundwater withdrawal, and population density. ③In irrigated regions, GWSA variations are mainly associated with groundwater extraction, cropland expansion, and evapotranspiration. Precipitation and surface water recharge exert buffering effects on groundwater depletion in most irrigated regions. However, intensive surface water abstraction has emerged as an important factor in groundwater storage decline in non-irrigated regions, particularly in the Tarim Basin and basins in the Hexi Corridor. These findings provide a scientific basis for the sustainable utilization and management of groundwater resources in arid regions.

     

/

返回文章
返回