Firstly

tendency factors of groundwater dynamic are evaluated and analyzed with measured data of the Luohuiqu irrigation district in Shanxi Province based on the Markov chain model of multiple element time-space sequence. The improved grey slope coefficient cor relation degree analysis method is applied to analyze the sensitive degree of various factors and groundwater depth. The concept of critical evaporation is put forward and the ARIMA model is established subsequently to predictev aporation. Results show that the tendency of groundwater dynamic in the irrigation district is worse. Evaporation is the main factor affecting groundwater dynamic and the interact ionamongst various factors forms coupling relationship under the complicated condition. When evaporation exceeds the 1800 mm critical value

groundwater level begins to rise and soil is subject to the threat of soil salinization. It is predicted that the evaporation in following several years almost exceeds the critical value and the precision of model is relatively high. It is feasible and practical to apply above method system to the investig ationon groundwater dynamic in irrigat ion district. The study provides a scientific basis for unified management and regulation of water resources.