Research On The Distributed Hydrological Model EasyDHM Applied In The Intake Area In Middle-route Of South-to-North Water Diversion

With the constant development and establishment of water resources management, the hydrology and water resources as an applied science, have been an indispensable research projects in our five-year plan. It not only has scientific foundation, but also provides theoretical support for the flood forecasting, water resources assessment and hydrologic analysis. Distributed hydrological model as a physical mechanism hydrological model, giving full consideration to the spatial differences in hydrologic parameters, combined with GIS and RS technology, can reproduce more accurate hydrological processes. Based on the simulation results of high accuracy, distributed hydrological model coupled with meteorological, ecological, environmental and other disciplines, analyze the climate change and human activities impact on the hydrological processes in-depth.Based on the "Eleventh Five-Year" Plan for major national scientific and technological support "Research on Water Resources Scheduling key technologies in Middle Route of the South-to-North Water Diversion Project " (2006BAB04A07), conduct hydrological process simulation on the intake area of the Middle Route Project ,using developed distributed dual hydrological model EasyDHM, carry out model parameters calibration and model evaluation. The model presented the independent parameters partitions with the topological relationships,to obtain higher precision, in order to reach the real hydrological processes. The rapid development of 3S technology,make obtaining the hydrological parameters values through remote sensing technology possible, to enhance and provide the possibility of further application by hydrological models.Based on EasyDHM model, hydrological modeling of watershed or study area with multiple entry points, multiple exit points, and trans-basin features such as, applied to different runoff mechanisms and convergence mechanisms, provides a platform for watershed management and scheduling. With the 1956-2005 data of hydro and metro gauges from the intake area, the paper simulated 16 typical regions for 5 consecutive years of rainfall runoff process to prove the feasibility of the model, Measured runoff and simulated results were compared, using runoff errors,correlation coefficient and Nash coefficient. After verification and analysis, EasyDHM model can achieve high simulation accuracy in large river basin.This paper selects Fuping area from Haihe River Basin to evaluate the model parameters, through multiple model simulations of the independent parameters assignments, concludes the variation of hydrological parameters and the effects on each part of the flood process.