【摘要】 基于DELFT3D模型研究了清澜-八门湾潟湖的水位分布和潮汐波内部结构,以及由于人类开垦引起的海岸线变化（以1962年、1985年和2008年为例）对潟湖水动力特性的影响。结果表明,清澜-八门湾潟湖潮汐是由多种分潮耦合而成的复杂驻波,其中K₁,O₁,M₂,S₂和M₄分潮的影响最大。由湾外向湾内传输,由于湾内红树林和浅滩引起的底部损耗增加,M₂,S₂,K₁和O₁分潮幅值减弱;M₄分潮幅值增强,表现出明显的浅水增幅效应;M₂和S₂分潮相位在文教河和文昌江领域表现出明显的干湿效应。不同年代海岸线的研究表明,1985年和2008年间,人类复垦导致潟湖及其潮汐汊道附近的红树林和滩涂区域严重破坏,海岸线缩减,引发了水位降低、纳潮量减少和潟湖潮汐汊道底摩擦弱化,从而削弱了干湿、潮呛和浅水效应。后果提示持续的人类复垦活动将会引发清澜-八门湾潮汐水动力环境的进一步恶化,可能导致未来发生更大的自然灾害。更多还原

【Abstract】 Here the tidal dynamics of the Qinglan-Eight Gate Bay are simulated using a two-dimensional flow model of DELFT3 D.The water-level distribution and the structure of tidal wave,as well as impacts of the human reclamation（taking the coastline changes of lagoon in 1962,1985 and 2008 as examples）,are studied.The results show that the tide of the Qinglan-Eight Gate Bay is a complex standing wave,consisting of various tidal components among which the K₁,O₁,M₂,S₂ and M₄ tides are dominant.During the process of the tidal transmission from outside to inside,the K₁,O₁,M₂ and S₂ amplitudes gradually decreases due to increase of the bottom dissipation caused by the mangrove and shoal,exhibiting the obvious tidal choking effect; in contrast,the M₄ amplitude decreases,indicating the obvious shoaling effect.The M₂ and S₂ phases show the minimal or maximal values in area of Wenjiao and Wenchang rivers,indicating occurrence of the wetting-drying effect.It is also shown that due to the human reclamation caused mainly by the removal of mangroves and tidal flats,the hydrodynamics in Qinglan-eight gate Bay has deteriorated,exhibited by reduction of the tidal volume and bottom friction,as well as weakening of the wetting-drying,tidal choking and the shoaling effect.More importantly,our finding indicates that the sustained activities of human reclamation will lead to further deterioration of tidal hydrodynamic environment in the QingLan-eight gate Bay,resulting in the great natural disaster in the future.更多还原