Application of integrated system of GIS-PModflow to water environment early warning in west of Songnen plain

With the effect of the groundwater table changes on the environment, the coupling technology with GIS and PModflow is used to define the threshold of the groundwater environment early warning in the paper.By means of this method, the phreatic water table without salinization is defined as the maximum limit, while the pumping limit of the phreatic water as the minimum limit.On the basis of the system model generalization, the water table is simulated and predicted The spatial analysis of GIS is used for overlaying the grid and the attribute judgment.The water environment precaut ion compares the predicted water with the threshold water table.Results show that the precaution state occurs more in 2015 than 1999, and mainly with the secondary salinization due to the phreatic water table uplift.