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According to precipitation data from 1951 to 2002, the precipitation distribution characteristics and variation tendency were analyzed. There was great variation in year-to-year precipitation with the maximum being five times greater than the minimum. The seasonal distributions were quite uneven with a general downward trend; especially since 1997 precipitation has been smaller than the normal. By means of monthly precipitation and temperature data from 1951 to 2002 and an empirical formula of land surface evaporation, the land-surface evaporating, evaporating coefficient and available precipitation coefficient were calculated; it is concluded that water resources and precipitation have similar variation characteristics and there occurred frequently droughts in spring in Taian. Through analyzing the underground water level data from 1984 to 2002, the following conclusions are arrived: the underground water level changes basically with precipitation; there is a general downward tendency and underground water resources decrease correspondingly; especially the underground water level declines year by year since 1995. Two solutions to mitigate the shortage of water resources are proposed: increasing precipitation through artificial rain enhancement and economizing water resources use.