A study On the variation and forecasting m odels of groundwater level an d draining waterlogging in cultivated soil layersin the Jianghuai Valley

The annual and interannual variances of groundwater level and the relationships among the groundwater level and the initial soil moisture，the initial groundwater level，temperature，sunshine，reference crop evapotranspiration，evapo-ration，precipitation in the Jianghuai Valley were analyzed．The forecasting models of groundwater level were built with step regr ession method ，the degrees of providing water were calculated with relative analyses method and the draining wa-terlogging mod el in cultivated soil layers was built．