ESTIMATING EVAPOTRANSPIRATION BY NATURAL VEGETATION IN THE HEIHE RIVER BASIN WITH A DISTRIBUTED HYDROLOGICAL MODEL (GISMOD)
Understanding hydrological processes of natural ecosystems is important for the management of water resources, ecosystem and environment in northwestern China.Evapotranspiration is one of the most important elements in hydrological processes.Different types of vegetation have different characteristics of water demands at growing stages, indicating that total leaf area and root water uptake of each plant might differ.In this paper, a distributed hydrological model, Grid—based Integrated Surface—groundwater model (GISMOD), was developed to estimate evapotranspiration by vegetation using an agro— meteorology theorybased method.The dynamic characteristics of Leaf Area Index (LAI) for different natural vegetation were estimated based on effective accumulated temperature and soil water content.Precipitation intercepted by plants, evaporation from ground surface and plant transpiration were estimated by GISMOD according to empirical equation of plant water requirement, potential evapotranspiration (PET), allocation characteristics of available water resources and simulated LAI data.A case study in the Heihe River basin was presented in order to evaluate model performance for estimating variability of evapotranspiration and LAI.Simulation results were consistent with actual situation and may be helpful in the future for the management of water resources
hydrological modelevapotranspirationleaf area indexHeihe River
国家科技期刊平台
NSTL
万方数据
维普
