The main aim in this research is comparison the parameters of some storm events in the watershed using two loss models in Unit hydrograph method by HEC-HMS. SCS Curve Number and Green-Ampt methods by developing loss m...The main aim in this research is comparison the parameters of some storm events in the watershed using two loss models in Unit hydrograph method by HEC-HMS. SCS Curve Number and Green-Ampt methods by developing loss model as a major component in runoff and flood modeling. The study is conducted in the Kuala Lumpurwatershed with674 km2 area located in Klang basin inMalaysia. The catchment delineation is generated for the Klang watershed to get sub-watershed parameters by using HEC-GeoHMS extension in ARCGIS. Then all the necessary parameters are assigned to the models applied in this study to run the runoff and flood model. The results showed that there was no significant difference between the SCS-CN and Green-Ampt loss method applied in the Klang watershed. Estimated direct runoff and Peak discharge (r = 0.98) indicates a statistically positive correlations between the results of the study. And also it has been attempted to use objective functions in HEC-HMS (percent error peaks and percent error volume) to classify the methods. The selection of best method is on the base of considering least difference between the results of simulation to observed events in hydrographs so that it can address which model is suit for runoff-flood simulation in Klang watershed. Results showed that SCS CN and Green-Ampt methods, in three events by fitting with percent error in peak and percent error in volume had no significant difference.展开更多
The main purpose of this study was to forecast the inflow to Hongze Lake using the Xin＇anjiang rainfall-runoff model. The upper area of Hongze Lake in the Huaihe Basin was divided into 23 sub-basins, including the su...The main purpose of this study was to forecast the inflow to Hongze Lake using the Xin＇anjiang rainfall-runoff model. The upper area of Hongze Lake in the Huaihe Basin was divided into 23 sub-basins, including the surface of Hongze Lake. The influence of reservoirs and gates on flood forecasting was considered in a practical and simple way. With a one-day time step, the linear and non-linear Muskingum method was used for channel flood routing, and the least-square regression model was used for real-time correction in flood forecasting. Representative historical data were collected for the model calibration. The hydrological model parameters for each sub-basin were calibrated individually, so the parameters of the Xin＇anjiang model were different for different sub-basins. This flood forecasting system was used in the real-time simulation of the large flood in 2005 and the results are satisfactory when compared with measured data from the flood.展开更多
A grid-based distributed hydrological model, the Block-wise use of TOPMODEL （BTOPMC）, which was developed from the original TOPMODEL, was used for hydrological daily rainfall-runoff simulation. In the BTOPMC model, ...A grid-based distributed hydrological model, the Block-wise use of TOPMODEL （BTOPMC）, which was developed from the original TOPMODEL, was used for hydrological daily rainfall-runoff simulation. In the BTOPMC model, the runoff is explicitly calculated on a cell-by-cell basis, and the Muskingum-Cunge flow concentration method is used. In order to test the model＇s applicability, the BTOPMC model and the Xin＇anjiang model were applied to the simulation of a humid watershed and a semi-humid to semi-arid watershed in China. The model parameters were optimized with the Shuffle Complex Evolution （SCE-UA） method. Results show that both models can effectively simulate the daily hydrograph in humid watersheds, but that the BTOPMC model performs poorly in semi-humid to semi-arid watersheds. The excess-infiltration mechanism should be incorporated into the BTOPMC model to broaden the model＇s applicability.展开更多
Urban highway runoff samples from seventeen rainfall events were collected in Shanghai in 2011. The concentrations of ten heavy metals and sixteen polycyclic aromatic hydrocarbons PAHs are analyzed. The results show t...Urban highway runoff samples from seventeen rainfall events were collected in Shanghai in 2011. The concentrations of ten heavy metals and sixteen polycyclic aromatic hydrocarbons PAHs are analyzed. The results show that the heavy metal concentrations range within 0.50 to 51.80 As 0 to 20.80 Se 13.67 to 445.80 Zn 0 to 44.20 Pb 0 to 15.80 Ni 39.58 to 264.20 Fe 0 to 253.00 Mn 0 to 8.20 Cr 0 to 124.20 Cu and 159.83 to 536.40 μg/L Al . Se Pb Mn and Al concentrations in most samples exceed their corresponding criterion continuous concentrations CCCs while Zn and Cu concentrations exceed their criterion maximum concentrations CMCs .The concentrations ofΣPAHs range within 37.25 to 114.57 ng/L and concentrations of PAHs are all below their corresponding CCCs.Cu Zn and ΣPAHs show the first flush phenomenon. Analysis results of the modified Nemerow index method NIM indicate that runoff from eight rainfall events may have very strong biological toxicity effects four have strong effects three have moderate effects and only two have insignificant effects.Therefore it is concluded that urban highway runoff is a significant pollution source to aquatic ecosystems and needs immediate purification.展开更多
文摘The main aim in this research is comparison the parameters of some storm events in the watershed using two loss models in Unit hydrograph method by HEC-HMS. SCS Curve Number and Green-Ampt methods by developing loss model as a major component in runoff and flood modeling. The study is conducted in the Kuala Lumpurwatershed with674 km2 area located in Klang basin inMalaysia. The catchment delineation is generated for the Klang watershed to get sub-watershed parameters by using HEC-GeoHMS extension in ARCGIS. Then all the necessary parameters are assigned to the models applied in this study to run the runoff and flood model. The results showed that there was no significant difference between the SCS-CN and Green-Ampt loss method applied in the Klang watershed. Estimated direct runoff and Peak discharge (r = 0.98) indicates a statistically positive correlations between the results of the study. And also it has been attempted to use objective functions in HEC-HMS (percent error peaks and percent error volume) to classify the methods. The selection of best method is on the base of considering least difference between the results of simulation to observed events in hydrographs so that it can address which model is suit for runoff-flood simulation in Klang watershed. Results showed that SCS CN and Green-Ampt methods, in three events by fitting with percent error in peak and percent error in volume had no significant difference.
基金supported by the National Natural Science Foundation of China (Grant No. 50479017)the Program for Changjiang Scholars and Innovative Research Teams in Universities (Grant No. IRT071)
文摘The main purpose of this study was to forecast the inflow to Hongze Lake using the Xin＇anjiang rainfall-runoff model. The upper area of Hongze Lake in the Huaihe Basin was divided into 23 sub-basins, including the surface of Hongze Lake. The influence of reservoirs and gates on flood forecasting was considered in a practical and simple way. With a one-day time step, the linear and non-linear Muskingum method was used for channel flood routing, and the least-square regression model was used for real-time correction in flood forecasting. Representative historical data were collected for the model calibration. The hydrological model parameters for each sub-basin were calibrated individually, so the parameters of the Xin＇anjiang model were different for different sub-basins. This flood forecasting system was used in the real-time simulation of the large flood in 2005 and the results are satisfactory when compared with measured data from the flood.
基金supported by the Research Fund for Commonweal Trades (Meteorology) (Grants No.GYHY200706037, GYHY (QX) 2007-6-1,GYHY200906007,and GYHY201006038)the National Natural Science Foundation of China (Grants No.50479017 and 40971016)Program for Changjiang Scholars and Innovative Research Team in University (Grant No.IRT0717)
文摘A grid-based distributed hydrological model, the Block-wise use of TOPMODEL （BTOPMC）, which was developed from the original TOPMODEL, was used for hydrological daily rainfall-runoff simulation. In the BTOPMC model, the runoff is explicitly calculated on a cell-by-cell basis, and the Muskingum-Cunge flow concentration method is used. In order to test the model＇s applicability, the BTOPMC model and the Xin＇anjiang model were applied to the simulation of a humid watershed and a semi-humid to semi-arid watershed in China. The model parameters were optimized with the Shuffle Complex Evolution （SCE-UA） method. Results show that both models can effectively simulate the daily hydrograph in humid watersheds, but that the BTOPMC model performs poorly in semi-humid to semi-arid watersheds. The excess-infiltration mechanism should be incorporated into the BTOPMC model to broaden the model＇s applicability.
基金Key Project of Science and Technology Commission of Shanghai Municipality(No.11231202100)
文摘Urban highway runoff samples from seventeen rainfall events were collected in Shanghai in 2011. The concentrations of ten heavy metals and sixteen polycyclic aromatic hydrocarbons PAHs are analyzed. The results show that the heavy metal concentrations range within 0.50 to 51.80 As 0 to 20.80 Se 13.67 to 445.80 Zn 0 to 44.20 Pb 0 to 15.80 Ni 39.58 to 264.20 Fe 0 to 253.00 Mn 0 to 8.20 Cr 0 to 124.20 Cu and 159.83 to 536.40 μg/L Al . Se Pb Mn and Al concentrations in most samples exceed their corresponding criterion continuous concentrations CCCs while Zn and Cu concentrations exceed their criterion maximum concentrations CMCs .The concentrations ofΣPAHs range within 37.25 to 114.57 ng/L and concentrations of PAHs are all below their corresponding CCCs.Cu Zn and ΣPAHs show the first flush phenomenon. Analysis results of the modified Nemerow index method NIM indicate that runoff from eight rainfall events may have very strong biological toxicity effects four have strong effects three have moderate effects and only two have insignificant effects.Therefore it is concluded that urban highway runoff is a significant pollution source to aquatic ecosystems and needs immediate purification.
