Classification of annual dynamic of groundwater depth in Ejina delta

In this paper,the groundwater depth dynamic in a year in Ejina Delta was analyzed based on groundwater depth monitoring data(2010.4-2011.4) on one day intervals in 14 monitoring wells in Ejina Delta with descriptive statistical analysis,one variant linear regression direct analysis and K-means cluster analysis in SPSS18.0.The results showed that the groundwater depth dynamic had significant spatial heterogeneity in Ejina Delta,and could be divided into four fluctuation types.TypeⅠmainly occurred in the desert zone being remote from river.Groundwater table had weakly fluctuated but not significantly changed;typeⅡmainly occurred in riparian zone where groundwater and surface water continuously exchanged.Frequent lifting and decline of groundwater table was typical characteristics of the fluctuation type;type Ⅲ mainly occurred in the oasis zone located in the lower reaches of the Donghe River.The dynamic change of groundwater table was affected by human activities.Rapid lifting and slow decline of groundwater table was the typical characteristics of the fluctuation type;type Ⅳ mainly occurred in oasis surrounding area where was far from river.Groundwater table had been continuously declining in the study period.Constant and slow decline of groundwater table was the typical characteristics of the fluctuation type,which was related to groundwater with constant evapotranspiration and without recharge.