2002～2018年中国七大流域水储量变化及时空分布特征

基于 GRACE 重力卫星反演2002～2018年中国七大流域的水储量变化。研究表明，中国陆地水储量变化存在明显的地域分布特征，辽河、海河、黄河和淮河流域水储量总体上呈递减趋势，年均减少速率分别为-0.54±0.9 mm/a、-5.96±0.6 mm/a、-2.65±0.8 mm/a 和-1.94±1.2 mm/a。在海河流域，地下水严重超采导致水储量明显减少；松花江、长江、珠江流域水储量呈显著增加趋势，年均增长速率分别为4.52±1.1 mm/a、3.84±0.7 mm/a、4.87±1.1 mm/a。流域水储量峰值一般晚于最大降雨量月份，这是因为降雨转换为陆地水储量需要一定时间。

Changes and Spatio-Temporal Characteristics of Terrestrial Water Storage Variation in China’s Seven Main River Basins During 2002-2018

Based on the spherical harmonic coefficient products of the GRACE gravity satellite by CSR, we retrieve the changes of terrestrial water storage in China's seven major river basins from 2002 to 2018. Terrestrial water storage changes are obviously dependent on geographical distributions. The water storage of the Liaohe, Haihe, Huanghe and Huaihe river basins generally show decreasing trends, with average annual rates of -0.54±0.9 mm/a, -5.96±0.6 mm/a, -2.65±0.8 mm/a, -1.94±1.2 mm/a, respectively. The most significant decrease in water storage occurred in Haihe river basin, resulting plausibly from the overexploitation of groundwater for industrial and agricultural activities. In the Songhua river, Yangtze river, and Pearl river basins, the water storages show significant positive trends, with average annual rates of 4.52±1.1 mm/a, 3.84±0.7 mm/a, and 4.87±1.1 mm/a, respectively. The time of water storage peak of the basin generally lags behind that of the peak monthly precipitation, because it takes some time to convert rainfall into land water storage.