Dynamic research on groundwater in Changchun

Based on dynamic monitoring data of groundwater observation wells,the authors analyzed the dynamic variation trend and reason of main groundwater type in Changchun.Since 2000,the groundwater level has been in picking up state,and the depth of pore-water decreased for 0.16 m in loosening rocks and about 0.78 m in bedrock fissure water reduccd for each year,which was mainly caused by exploitation restriction of groundwater.The tendency of groundwater level of typical observation holes shows the groundwater level in shallow layer is closely related to air temperature,but there is a response lag for about 1～1.5 months.