Contemporary role of catchment water balance data for forest evapotranspiration research

Recently, catchment water balance measurements have not been used actively for examining forest evapotranspiration compared to process-based measurements based on meteorological and sap-flow methods. This paper overviewed the history of forest evapotranspiration studies and clarified what caused this situation. This paper then pointed out that catchment water balance measurements cannot be replaced completely by process-based measurements from the viewpoints of data accuracy and feasibility of measurements. This paper also pointed out that coordination of process-based measurements and catchment water balance measurements brings new insights. Furthermore, this paper proposed several important topics that should be examined by such coordination and also proposed measures to develop environments that promote such coordination.