利用GRACE数据分析中国区域地下水变化

Analysis of Regional Groundwater Changes in China by Using GRACE Data

利用GRACE和GLDAS数据计算了2003年1月—2012年12月我国长江中下游平原、西南地区、华北平原的地下水储量变化。长江中下游平原与西南地区地下水储量最低值在冬季、最高值在9月,华北平原地下水储量最低值在6月、最高值在12月,结合3个区域降水与农业耕作模式对地下水储量变化进行分析。西南地区地下水储量变化最显著的为云南省,可能与云南省的气温和喀斯特地貌有关。冬季华北平原冬小麦存在越冬期,灌溉需水量减少,地下水储量上升;春末处于冬小麦和夏玉米的轮作期,农业灌溉需水量增加地下水储量减少,达到一年中的最低值。

This paper uses GRACE and GLDAS data to calculate the changes of groundwater reserves in the plains of the middle and lower reaches of the Yangtze River,the southwestern region,and the North China Plain from Jan.2003 to Dec.2012.The lowest value of groundwater reserves in the middle and lower reaches of the Yangtze River is in the winter and the highest is in September.The lowest value of groundwater reserves in the North China Plain is in June and the highest is in December.This paper combines three regional precipitation and agricultural farming models to analyze changes in groundwater reserves.The most significant change in groundwater reserves in Southwest China is Yunnan Province,which may be related to temperature and karst landform in Yunnan Province.Since winter wheat in the North China Plain has wintering period,the irrigation water demand decreases,so groundwater reserves increase.At the end of spring winter wheat and summer maize are in rotation and agricultural irrigation water demand increases,groundwater reserves decrease,reaching the lowest value in a year.