Abstract: This paper deals with the measurement and analysis on the continuous time gradients and spatial gradients of oak community and its poapultionswith ZHT potetometer. The daily variation laws of transpiration intensityof tree、shrub and herb layer are obtained. The status of each populationin the community is suggested at the tranpiration physiology angle. Thetranspiration intensity is a physiological factor that can reflect the spatialpattern of population.

Key words: Oak, Transpiration