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Oak forest and grassland in the Tongshan forestry farm in Nanjing,China were selected,within which,4 sets EM50 was used to measure Soil Volumetric Water Content (DASVWC) at depths of 5cm,15cm,30cm respectively and air humidity was measured at the height of 2 m.All these data were recorded continuously for every 15 minutes during June,2010 to May,2011.Precipitation was measured in both two types of land use with a far distance transportation system for each mm precipitation.By analyzing the vertical-temporal variable quantity,variations of DASVWC and their correlation with meteorological factors,it was found that they were affected by precipitation,air temperature and humidity and DASVWC.Quite different from the variability law of DASVWC in the Yellow River watershed,where variability of DASVWC in the 5cm layer was lower than those in the 15 cm and 30 cm soil layer,in this research variability of DASVWC in the 0-5 layer was higher than those in the 15 cm and 30 cm soil layer in the two types of land use.DASVWC in oak forest in the 0-30 soil layer was lower compared with those in the grass land,showing decrease of DASVWC in the surface soil layer with increase of plant coverage.In the same type of land use,values of DASVWC at three layers showed linear regression outstandingly.During rain intervals indifferent seasons,DASVWC showed exponential correlation with time very significantly.