黄河流域地下水储量时空演变特征及影响因素分析

Spatio⁃Temporal Characteristics and Influencing Factors Analysis of GroundwaterStorage Variations in the Yellow River Basin

基于GRACE和GRACE Follow-On卫星及GLADS数据,考虑气候、植被等影响,构建了时间序列分解和随机森林算法耦合模型,揭示了2003—2022年黄河流域地下水储量时空变化特征及主要驱动过程。结果表明:近20 a黄河流域地下水储量显著减小,减小变率为-3.3 mm/a,其中汾河盆地和关中平原地区减小速度最快,变率为-15~-30 mm/a;气候呈暖干化趋势,植被绿度提高,蒸散发量显著增加;地下水储量的减小是植被覆盖增加、气温升高和蒸散发量增加共同作用导致地下水消耗量增加的结果;地下水储量空间变化主导因素差异显著,不同区域主导过程均由植被状况和气温的相互作用驱动。

Based on GRACE and GRACE Follow⁃On satellite,as well as the data of GLDAS,considering the impacts of climate and vegeta⁃tion,a coupled model of time series decomposition and random forest algorithms was built to reveal the spatial⁃temporal variations and driving processes of groundwater storage in the Yellow River Basin from 2003 to 2022.The results indicate that a)over the past 20 years,groundwa⁃ter storage in the basin has significantly decreased,with a rate of-3.3 mm/year,especially in the Fenhe River basin and Guanzhong Plain where the rates are the fastest,ranging from-15 mm/year to-30 mm/year.b)The climate of the basin shows a trend towards warmer and drier,with increased vegetation greenness and evapotranspiration.c)The reduction in groundwater storage is a result of increased groundwa⁃ter consumption caused by a combination of increased vegetation cover,rising temperatures and increased evapotranspiration.d)The domi⁃nant factors for spatial variations in groundwater storage differ significantly,with temperature and vegetation interactions driving the processes in different regions.