| Wenzhou which is an important port city in the southeast coast of China occupies few landbut with many people. In order to solve the serious shortage of land resources, most area inWenzhou conducts offshore construction projects on a large scale. However, the impact on themarine environment has become a new research topic after a lot of reclamation projects arecompleted. Our country is still in the exporatory stage on the research which is aboutthe cumulative influence of reclamation projects on the marine environment. So to grasp theimpact on the marine reclamation hydrodynamic environment and to study the combined effects ofmultiple reclamation works on the marine environmet will play a positive and important role orpractical significance for the region ’s marine economy development in Wenzhou. Thispaper mainly use two methods to analyze and evaluate tidal current superposition effect of thereclamation projects in Wenzhou coastal. This paper mainly uses two methods which arecomparing the front an rear monitoring data marine construction works and numerical simulationto analyze and evaluate tidal current superposition effect of the reclamation projects in Wenzhoucoastal. This thesis is composed of five chapters as follows:In chapter1,we systematically introduce the background and significance on studying thehydrodynamic impact of marine construction project in the seas adjacent to Wenzhou. We discussthe related researches which the previous have done in our country. The main research methodsand contents are also introduced.In chapter2, we generalize the geographical location, topography, weather, waves and runoffin the study area and we introducethe hydrodynamic characteristic in the study area. Also wesummarize the reclamation situation in the research area for years.In chapter3, this paper have collected the measured tides and tidal currents measured data indifferent stages of many projects in past three to five years near the Wenzhou offshore. Theharmonic method is used to analyze tide and tidal currents data observed at five stations in the seaadjacent to Wenhou. The tidal amplitudes of M2constituent are between170～215cm and thelags are between242～303°.According to the comparison of analytical results of harmonic constants of these stations in2007,2010,2011. The maximum change of tidal amplitudes andphase-lags range for the main semidiurnal tides(M2、S2、N2),the diurnal tide(K1、O1)and theshallow water tide(M4、MS4、M6) are1.3～4.8cm and1.3～7°,respectively. The ellipticity Kfor M2constituent is-0.04~0.08in2007，The ellipticity K for M2constituent is-0.03~0.087in2011.The ellipse major axis of M2constituent is slightly smaller in2007compared with2011.The numerical value of the velocity average decrease is0.08m/s.therefore, thesuperimposed influences of the tide and tidal current field for construction engineering inWenzhou offshore is not significant.In chapter4,after analyzing the tide and tidal current characteristic of Wenzhou offshore, thispaper used an unstructured grid and finite-volume coastal ocean model (FVCOM) totest the result of simulation. The maximum absolute differences of elevation、flow velocity anddirection are0.11~0.18、2.6~4.2cm/s and6.5°~9.5°.The new shoreline and depth producedby the construction projects are closed in major years, the tide and tidal current field for the newshoreline and depth are constructed. This characterizes the superimposed influences ofconstruction engineering in Wenzhou offshore.In chapter5, we sum up superimposed influences of construction engineering in Yueqing Bay,Oujiang River, Aojiang River and adjacent areas. |
PDF Full Text Request