An improved 3-D ECOM-si model was used to study the impact of seasonal tide variation on saltwater intrusion into the Changjiang River estuary, especially at the bifurcation of the North Branch （NB） and the South Br...An improved 3-D ECOM-si model was used to study the impact of seasonal tide variation on saltwater intrusion into the Changjiang River estuary, especially at the bifurcation of the North Branch （NB） and the South Branch （SB）. The study assumes that the fiver discharge and wind are constant. The model successfully reproduced the saltwater intrusion. During spring tide, there is water and salt spillover （WSO and SSO） from the NB into the SB, and tidally averaged （net） water and salt fluxes are 985 m3/s and 24.8 ton/s, respectively. During neap tide, the WSO disappears and its net water flux is 122 m3/s. Meanwhile, the SSO continues, with net salt flux of 1.01 ton/s, much smaller than during spring tide. Because the tidal range during spring tide is smaller in June than in March, overall saltwater intrusion is weaker in June than in March during that tidal period. However, the WSO and SSO still exist in June. Net water and salt fluxes in that month are 622 m3/s and 15.35 ton/s, respectively, decreasing by 363 m3/s and 9.45 ton/s over those in March. Because tidal range during neap tide is greater in June than in March, saltwater intrusion in June is stronger than in March during that tidal period. The WSO and SSO appear in June, with net water and salt fluxes of 280 m3/s and 8.55 ton/s, respectively, increasing by 402 m3/s and 7.54 ton/s over those in March. Saltwater intrusion in the estuary is controlled by the fiver discharge, semi-diurnal flood-ebb tide, semi-monthly spring or neap tide, and seasonal tide variation.展开更多
Using the RMA4 water quality model to simulate the water quality of Neijiang river in Zhenjiang, the result showed that： in the dry season the ranges of the concentration of various pollutants simulation of Neijiang ...Using the RMA4 water quality model to simulate the water quality of Neijiang river in Zhenjiang, the result showed that： in the dry season the ranges of the concentration of various pollutants simulation of Neijiang were BOD5 3.2-5.2 mg/L, CODMn 4.7-6.8 mg/L, NH3-N 0.46-1.8 mg/L, TP 0.23-0.48 mg/L, and in the rainy period, the ranges of the concentration of various pollutants simulation of Neijiang were BOD5 0.69-0.73 mg/L, CODM, 1.9-2.3 mg/L, NH3-N 0.25-0.38 mg/L, TP 0.14-0.17 mg/L.These simulated values were closed to the monitoring values of pollution concentrations of Neijiang, which indicated that RMA4 was certain practical in the river water quality simulation, and simulation results have a certain degree of reliability, and it provides a scientific planning and management method for the river pollution control.展开更多
基金Supported by the National Basic Science Research Program of Global Change Research(No.2010CB951201)the Funds for Creative Research Groups of China(No.41021064)the Marine Special Program for Scientific Research on Public Causes(No.201005019)
文摘An improved 3-D ECOM-si model was used to study the impact of seasonal tide variation on saltwater intrusion into the Changjiang River estuary, especially at the bifurcation of the North Branch （NB） and the South Branch （SB）. The study assumes that the fiver discharge and wind are constant. The model successfully reproduced the saltwater intrusion. During spring tide, there is water and salt spillover （WSO and SSO） from the NB into the SB, and tidally averaged （net） water and salt fluxes are 985 m3/s and 24.8 ton/s, respectively. During neap tide, the WSO disappears and its net water flux is 122 m3/s. Meanwhile, the SSO continues, with net salt flux of 1.01 ton/s, much smaller than during spring tide. Because the tidal range during spring tide is smaller in June than in March, overall saltwater intrusion is weaker in June than in March during that tidal period. However, the WSO and SSO still exist in June. Net water and salt fluxes in that month are 622 m3/s and 15.35 ton/s, respectively, decreasing by 363 m3/s and 9.45 ton/s over those in March. Because tidal range during neap tide is greater in June than in March, saltwater intrusion in June is stronger than in March during that tidal period. The WSO and SSO appear in June, with net water and salt fluxes of 280 m3/s and 8.55 ton/s, respectively, increasing by 402 m3/s and 7.54 ton/s over those in March. Saltwater intrusion in the estuary is controlled by the fiver discharge, semi-diurnal flood-ebb tide, semi-monthly spring or neap tide, and seasonal tide variation.
文摘Using the RMA4 water quality model to simulate the water quality of Neijiang river in Zhenjiang, the result showed that： in the dry season the ranges of the concentration of various pollutants simulation of Neijiang were BOD5 3.2-5.2 mg/L, CODMn 4.7-6.8 mg/L, NH3-N 0.46-1.8 mg/L, TP 0.23-0.48 mg/L, and in the rainy period, the ranges of the concentration of various pollutants simulation of Neijiang were BOD5 0.69-0.73 mg/L, CODM, 1.9-2.3 mg/L, NH3-N 0.25-0.38 mg/L, TP 0.14-0.17 mg/L.These simulated values were closed to the monitoring values of pollution concentrations of Neijiang, which indicated that RMA4 was certain practical in the river water quality simulation, and simulation results have a certain degree of reliability, and it provides a scientific planning and management method for the river pollution control.
