Interannual variability of evapotranspiration based on distributed hydrological model in Xinjiang catchment, Poyang Lake

Evapotranspiration (ET) is one of the hydrologic parameters and a major component of the water cycle and important in water resource development and management. The paper studies the interannual variability and spatial distribution of ET in Xinjiang catchment based on the WATLAC (Water Flow Model for Lake Catchment) model. The results show that the interception evaporation is maximal in June and August and minimal in winter, the soil evaporation is maximal between July and September and minimal between January and March, which is inverse proportion to the vegetation coverage. The average interannual distribution of stream evaporation is consistent with the rainfall. And the annual interception evaporation is larger in south of study area than ones in north. The spatial distribution of LAI reflects the variation of interception evaporation. The soil evaporation is large in south and northeast of study area, but very small in the downstream area.