Flooding is the most prevalent and costly natural disaster in the world and building reservoirs is one of the major structural measures for flood control and management. In this paper, a framework was proposed to eval...Flooding is the most prevalent and costly natural disaster in the world and building reservoirs is one of the major structural measures for flood control and management. In this paper, a framework was proposed to evaluate functions of reservoirs′ locations and magnitudes on daily peak flow attenuation for a large basin of China, namely Ganjiang River Basin. In this study, the Xinanjiang model was adopted to simulate inflows of the reservoirs and flood hydrographs of all sub-catchments of the basin, and simple reservoir operation rules were established for calculating outflows of the reservoirs. Four reservoirs scenarios were established to analyze reservoirs′ locations on daily peak flow attenuation. The results showed that: 1) reservoirs attenuated the peak discharges for all simulated floods, when the flood storage capacities increase as new reservoirs were built, the peak discharge attenuation by reservoirs showed an increasing tendency both in absolute and relative measures; 2) reservoirs attenuated more peak discharge relatively for small floods than for large ones; 3) reservoirs reduced the peak discharge more efficiently for the floods with single peak or multi peaks with main peak occurred first; and 4) effect of upstream reservoirs on peak attenuation decreased from upper reaches to lower reaches; upstream and midstream reservoirs played important roles in decreasing peak discharge both at middle and lower reaches, and downstream reservoirs had less effect on large peak discharge attenuation at outlet of the basin. The proposed framework of evaluating functions of multiple reservoirs′ storage capacities and locations on peak attenuation is valuable for flood control planning and management at basin scale.展开更多
To improve the Xinanjiang model, the runoff generating from infiltration excess is added to the model. The another 6 parameters are added to Xinanjiang model. In prin ciple, the improved Xinanjiang model can be used t...To improve the Xinanjiang model, the runoff generating from infiltration excess is added to the model. The another 6 parameters are added to Xinanjiang model. In prin ciple, the improved Xinanjiang model can be used to simulate runoff in the humid, semi-humid and also semi-arid regions. The application in Yi River shows the improved Xinanjiang model could forecast discharge with higher acetrracy and can satisfy the practical requirements,It also shows thai the improved model is reasonable.展开更多
The Xinanjiang(XAJ)model has been successfully applied in humid and semi-humid regions.Considering the geomorphologic factors to accurately estimate floods,this study adopted the geomorphologic instantaneous unit hydr...The Xinanjiang(XAJ)model has been successfully applied in humid and semi-humid regions.Considering the geomorphologic factors to accurately estimate floods,this study adopted the geomorphologic instantaneous unit hydrograph(GIUH)method to calculate the surface runoff instead of the experience unit hydrograph(EUH)in the original model.The geomorphologic factors of the case study basin were obtained by using a digital elevation model(DEM)and the Terrain analysis using Digital Elevation Models(TauDEM).Furthermore,the dynamic Muskingum model was used for the channel flood routing.This study focused on the simulation of heavy precipitation and floods over the Chong River,which is a tributary river to the Songhua River on the right bank in northeast China.The detailed steps of the method were shown,up to the estimated value of flood runoff discharges and flood peaks and their comparison with observed values.The average deterministic coefficients(DCs)of model calibration and validation were 0.89 and 0.83,respectively.The results show that the model precision is high and the model is feasible for flood forecasting.Lastly,some methodological perspectives to enhance the method are presented.展开更多
In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies,...In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies, there is a general opinion that no single-objective function can represent all important characteristics of even one specific hydrological variable(e.g., streamflow).Thus hydrologists must turn to multi-objective calibration.In this study, we demonstrated that an optimized single-objective function can compromise multi-response modes(i.e., multi-objective functions) of the hydrograph, which is defined as summation of a power function of the absolute error between observed and simulated streamflow with the exponent of power function optimized for specific watersheds.The new objective function was applied to 196 model parameter estimation experiment(MOPEX) watersheds across the eastern United States using the semi-distributed Xinanjiang hydrological model.The optimized exponent value for each watershed was obtained by targeting four popular objective functions focusing on peak flows, low flows, water balance, and flashiness, respectively.Results showed that the optimized single-objective function can achieve a better hydrograph simulation compared to the traditional single-objective function Nash-Sutcliffe efficiency coefficient for most watersheds, and balance high flow part and low flow part of the hydrograph without substantial differences compared to multi-objective calibration.The proposed optimal single-objective function can be practically adopted in the hydrological modeling if the optimal exponent value could be determined a priori according to hydrological/climatic/landscape characteristics in a specific watershed.展开更多
基金Commonwealth and Specialized Programs for Scientific Research,Ministry of Water Resources of China(No.200901042)
文摘Flooding is the most prevalent and costly natural disaster in the world and building reservoirs is one of the major structural measures for flood control and management. In this paper, a framework was proposed to evaluate functions of reservoirs′ locations and magnitudes on daily peak flow attenuation for a large basin of China, namely Ganjiang River Basin. In this study, the Xinanjiang model was adopted to simulate inflows of the reservoirs and flood hydrographs of all sub-catchments of the basin, and simple reservoir operation rules were established for calculating outflows of the reservoirs. Four reservoirs scenarios were established to analyze reservoirs′ locations on daily peak flow attenuation. The results showed that: 1) reservoirs attenuated the peak discharges for all simulated floods, when the flood storage capacities increase as new reservoirs were built, the peak discharge attenuation by reservoirs showed an increasing tendency both in absolute and relative measures; 2) reservoirs attenuated more peak discharge relatively for small floods than for large ones; 3) reservoirs reduced the peak discharge more efficiently for the floods with single peak or multi peaks with main peak occurred first; and 4) effect of upstream reservoirs on peak attenuation decreased from upper reaches to lower reaches; upstream and midstream reservoirs played important roles in decreasing peak discharge both at middle and lower reaches, and downstream reservoirs had less effect on large peak discharge attenuation at outlet of the basin. The proposed framework of evaluating functions of multiple reservoirs′ storage capacities and locations on peak attenuation is valuable for flood control planning and management at basin scale.
基金this research was funded by the Chinese National Natural Sciences Foundation (40671033 and 40671032)China MOST"863"Project(2006AA10Z228)China MOST"973"Project (2009CB421307)
文摘To improve the Xinanjiang model, the runoff generating from infiltration excess is added to the model. The another 6 parameters are added to Xinanjiang model. In prin ciple, the improved Xinanjiang model can be used to simulate runoff in the humid, semi-humid and also semi-arid regions. The application in Yi River shows the improved Xinanjiang model could forecast discharge with higher acetrracy and can satisfy the practical requirements,It also shows thai the improved model is reasonable.
文摘The Xinanjiang(XAJ)model has been successfully applied in humid and semi-humid regions.Considering the geomorphologic factors to accurately estimate floods,this study adopted the geomorphologic instantaneous unit hydrograph(GIUH)method to calculate the surface runoff instead of the experience unit hydrograph(EUH)in the original model.The geomorphologic factors of the case study basin were obtained by using a digital elevation model(DEM)and the Terrain analysis using Digital Elevation Models(TauDEM).Furthermore,the dynamic Muskingum model was used for the channel flood routing.This study focused on the simulation of heavy precipitation and floods over the Chong River,which is a tributary river to the Songhua River on the right bank in northeast China.The detailed steps of the method were shown,up to the estimated value of flood runoff discharges and flood peaks and their comparison with observed values.The average deterministic coefficients(DCs)of model calibration and validation were 0.89 and 0.83,respectively.The results show that the model precision is high and the model is feasible for flood forecasting.Lastly,some methodological perspectives to enhance the method are presented.
基金Under the auspices of National Key Research and Development Program of China(No.2016YFC0402701)National Natural Science Foundation of China(No.51825902)
文摘In the calibration of hydrological models, evaluation criteria are explicitly and quantitatively defined as single-or multi-objective functions when utilizing automatic calibration approaches.In most previous studies, there is a general opinion that no single-objective function can represent all important characteristics of even one specific hydrological variable(e.g., streamflow).Thus hydrologists must turn to multi-objective calibration.In this study, we demonstrated that an optimized single-objective function can compromise multi-response modes(i.e., multi-objective functions) of the hydrograph, which is defined as summation of a power function of the absolute error between observed and simulated streamflow with the exponent of power function optimized for specific watersheds.The new objective function was applied to 196 model parameter estimation experiment(MOPEX) watersheds across the eastern United States using the semi-distributed Xinanjiang hydrological model.The optimized exponent value for each watershed was obtained by targeting four popular objective functions focusing on peak flows, low flows, water balance, and flashiness, respectively.Results showed that the optimized single-objective function can achieve a better hydrograph simulation compared to the traditional single-objective function Nash-Sutcliffe efficiency coefficient for most watersheds, and balance high flow part and low flow part of the hydrograph without substantial differences compared to multi-objective calibration.The proposed optimal single-objective function can be practically adopted in the hydrological modeling if the optimal exponent value could be determined a priori according to hydrological/climatic/landscape characteristics in a specific watershed.
