Development of a distributed model for eco-hydrological simulation in the upper Heihe River

Abstract:

Development of distributed eco-hydrological model is quite important for water resources management in the arid regions. Based on the analysis of topography and spatial vegetation patterns, a distributed eco-hydrological model was developed and applied to the upper Heihe River basin which was a typical inland basin in Northwest China. Interaction between the vegetation dynamics, hillslope hydrological processes and frozen soil processes were described in the model. A method using the ”subbasin-flow interval-grid-hillslope” system was developed for catchment discretization. Hillslope was the basic unit for eco-hydrological simulation. Key eco-hydrological processes includes vegetation growth, evaporation, infiltration, soil moisture move, groundwater flow and surface flow were simulated on the hillslope. Numerical simulation experiment showed that topography parameterization significantly influenced the eco-hydrological simulation. Concave hillslopes lead to larger flood peaks then linear hillslopes. Spatial variability of radiation due to the variability of slope and aspect played on important role in energy and water balance. Frozen soil changes and vegetation changes showed large effects the hydrological process.