近30年来白洋淀流域平原区地下水位动态变化及原因分析

白洋淀流域平原区是华北平原的农业高产区域，灌溉用水主要靠开采地下水。近几十年来，白洋淀地下水位下降严重，在1974年-2007年。该区域地下水埋深以平均每年0．51m的速率下降，1980年以后下降速率明显加速，在2000年-2007年年均下降速率达到了0．99m。引起地下水位持续下降的主要原因是地下水超采严重，且用水高峰期遭遇枯水期，尤其体现在1980年以后年降水偏枯．同时社会经济用水量维持在高峰阶段。低效的农业用水模式及地下水超采已经严重制约了白洋淀地区水资源的可持续利用。

Dynamics and Causes of Groundwater Table Change in Plain Area of Baiyangdian Basin in last 30 Years

The plain area of Baiyangdian basin is a grain high-yieid area in north China plain.The agricultural irrigation water was mostly obtained from groundwater.In recent decades, the groundwater level in this area has continually dropped seriously.According to statistics, the groundwater table buried depth has dropped at the average annual rate of about 0.51 meters from 1974 to 2007.After 1980, The declining rate accelerated significantly, and the average annual rate of 2000-2007 has reached 0.99 meters.The main factors to lead groundwater level dropping are the serious over-exploitation of groundwater, and the overlapping of peak water use period and dry season.Annual precipitation has been lower than normal years since 1980, and water consumption at its highest.The low irrigation water use efficiency in farmland and over-exploitation of groundwater have limited the sustainable utilization of water resource in this area.