Variation of Shallow Groundwater Level in Shijiazhuang Plain

Based on the analysis of the dynamic characteristics of shallow groundwater in Shijiazhuang Plain,the inter-annual and intra-annual dynamic variation law and effect elements(groundwater exploitation and precipitation) of groundwater level lowering were identified.The results showed the inter-annual falling trend of groundwater level was apparently.For each month,the inter-annual lowering rate of groundwater level was different,which showed a more rapid falling of water table during January and May than that during June and December.The variation of groundwater level was affected by the groundwater exploitation and precipitation.In terms of the inter-annual variation of groundwater level,increasing of groundwater exploitation led to the continuous lowering of groundwater level.It was showed that precipitation affected groundwater dynamic changes,according to rising or slow falling of groundwater level in wet years but rapid falling in dry years.In terms of the intra-annual variation of groundwater level,increasing of groundwater exploitation and low precipitation induced the lowering of groundwater level from March,while the increasing of precipitation and decreasing of groundwater exploitation led to the recovery of groundwater level from June.