抄録
Evapotranspiration is one of the most impotant components of hydrological cycle in forested basins for water resources planning and management. Because transpiration is closely related to soil moisture, it plays an impotant role especially in the time of drought. This study focuses on transpiration decline caused by the limitation of extractable soil water and the increase of vapor pressure deficit. A mathematical transpiration model developed by authors was applied to the observation obtained in a small forested basin and a critical soil moisture at which transpiration began to decline was identified. The proposed model could describe the transpiration decline in the basin during drought periods.
