Numerical Simulation Of The Influences Of Planning Reclamation Project On Hydrodynamic And Sediment Environments Of Dongshan Bay

Nowadays,the contradiction between the rapid growth of coastal city's economy and the lack of land resources is getting even more intensified than ever before,and the land reclamation project can assist to settle the problem quickly.While such programmes are able to offer a great quantity of land,they can exert some side effects on the environment of waters at the same time,especially when we carry out the programme in inner bay,the results will be more serious and the environment will find it more difficult to recover.In order to exploit the resource more reasonably and protect the marine environment,it's important to carry out research about the influence of inner bay's reclamation on the hydrodynamic and sediment environments.This paper reviewed the research statuses regarding the influence of reclamation on hydrodynamic and sediment environments,established a 2-D numerical tidal current model based on triangle mesh,and simulated the hydrodynamic field of Dongshan Bay.The numerical results have been validated using the observation data.Under the premise that the model met the requirement of precision,the model was used in the Dongshan Bay reclamation programme,in order to discuss the change of hydrodynamic field in three different projects,from the aspect of tide volume,seawater exchange,flow field,velocity change and other aspects.On the base of numerical tidal current model,combined empirical formula of sediment deposition,we discussed the status of sediment deposition after the reclamation.According to the research,the reclamation reduces the tide volume of Dongshan Bay,and recedes the capacity of seawater exchange;tidal field redistributes along the edge of reclamation area,the bigger reclamation area is,the larger extent of flow field is influenced;the change of sediment deposition is consistent with the change of velocity change,the bigger reclamation area is,the larger extent of sediment deposition is influenced.Based on the former paper's simulation result,by adopting the evaluation index system of hydrological dynamics established by Gulf and Environment ResearchInstitute of Fujian Province,the paper evaluates different plans of Dongshan Bay reclamation.Plan ? and plan ? are suggested to be acceptable,while the plan ?should be treated carefully.The value of Reclamation Intensity Indexs(RII)of Dongshan Bay also has been discussed,in order to provide the basis for controlling the scale of reclamation.