| 摘要: |
| 海滩地形变化是复杂的地形动力过程作用的结果，包含着诸多的时间和空间尺度特征信息。本研究利用经验正交函数（Empirical Orthogonal Function， EOF），对2018年4月至2019年3月的琼州海峡南岸铺前湾、海口湾和澄迈湾海滩剖面数据进行了分析。结果表明：①前3个时空函数可以代表琼州海峡南岸海滩主要变化模态。其中第1模态都表现为淤积，铺前湾和海口湾海滩呈现夏秋淤冬春冲的季节性特征，澄迈湾为夏秋冲冬春淤的季节性特征。第2、3模态则可能是风暴作用、潮位影响下的沉积物在滩面上的迁移或波浪随潮位变化引起，与海湾区域地形、入射波向、泥沙来源、潮差、波高、风暴路径等有关。②铺前湾和海口湾海域建设的人工岛加剧了海湾的遮蔽程度，促进了海湾部分岸段海滩淤积，海滩还要一段时间才能达到新的平衡。③作为次控因素之一，观测期间台风对海滩的影响程度有限。同时，海滩对台风响应与台风强度、登陆距离、相对台风的方位以及当地地形遮蔽程度密切相关。 |
| 关键词: 海洋地质学 经验正交函数 海滩剖面 季节变化 台风影响 琼州海峡 |
| DOI：10.3969/J.ISSN.2095-4972.2021.04.015 |
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| 基金项目:国家自然科学基金资助项目(41676079)；南方海洋科学与工程广东省实验室（湛江）资助项目（ZJW-2019-08）；广东海洋大学创新强校工程资助项目(Q18307) |
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| Dynamic variation characteristics of beach profile along southern coast of Qiongzhou Strait |
| HU Taihuan,LI Zhiqiang,ZHU Shibing,CHEN Ruifeng,LI Gaocong,ZENG Chunhua,ZHANG Huiling |
| (College of Electronic and Information Engineering, Guangdong Ocean University, Zhanjiang 524088， China;Marine Resources Big Data Center of South China Sea, Southern Marine Science and Engineering Guangdong Laboratory (Zhanjiang), Zhanjiang 524000;College of Ocean Engineering, Guangdong Ocean University, Zhanjiang 524088, China) |
| Abstract: |
| The change of beach topography is the result of complex topographic dynamic process with many information of temporal and spatial characters. In this paper, the empirical orthogonal function (EOF) was used to analyze beach profile data of Puqian Bay, Haikou Bay and Chengmai Bay in the southern coast of Qiongzhou Strait from April 2018 to March 2019. Results show that first, the first three spatial and temporal functions could represent the main modes for the changes of beach on the southern coast of Qiongzhou Strait. The first mode represented the beach accretion. Beaches of Puqian Bay and Haikou Bay showed the seasonal characteristics of silting from summer to autumn and eroding from winter to spring. Chengmai Bays beach had the seasonal characteristics of eroding in summer and autumn and silting in winter and spring. The second and third modes might be caused by the migration of the sediments on the beach influenced by storms, tidal levels, or by changes of the wave height and the tidal level, which were related to bay area topography, incident wave direction, sediment source, tidal range, wave height, storm path, etc. Second, artificial islands in Puqian Bay and Haikou Bay had increased the bays sheltering and promoted the silting of partial gulfs beaches. It takes times before the beach reached a new balance. Third, as a secondary control factor during the observation typhoon impacts on the beaches were found limited. At the same time, the beach response to typhoons was closely related to typhoon intensity, landing distance, relative typhoon position and degree of local terrain shelter. |
| Key words: marine geology empirical orthogonal function beach profile seasonal change typhoon influence Qiongzhou Strait |
