雷州半岛南部海滩对1720号台风(卡努)的响应研究

海滩风暴响应的观测和研究有助于加深对海滩过程的认识。2017年10月16日台风“卡努”在广东徐闻县沿海登陆, 对雷州半岛南部海滩造成了显著影响。文章通过海滩剖面观测和沉积物采样, 探讨了该区域海滩对台风“卡努”的响应特征, 得出以下主要结论。1) 台风浪作用下, 海滩表层沉积物变粗, 分选性变差。海滩状态朝着更加消散的状态转化, 以缓冲和适应高强度波浪的能量。2) 受到岬角和湾口朝向、大小等因素影响, 各海滩及同一海滩的不同岸段剖面变化表现出差异性。台风作用后海滩可能形成水下沙坝, 或者在海滩上部形成滩肩等特征地形。因此, 研究海滩风暴响应时, 要注意到区域地质地貌的影响。3) 水下礁坪、巨型砂质岬角等因素影响了台风过程灯楼角海滩的变化。对这种海滩–珊瑚礁坪系统的风暴效应, 还需要进行进一步探讨和更详细的观测和研究。

Study on beach response to Typhoon Khanun (No. 1720) along southern Leizhou Peninsula

Observations and research on beach responses to storms help deepen our understanding of beach processes. Typhoon Khanun (No. 1720) made landfall in Xuwen, Guangdong on October 16, 2017. The typhoon caused significant impacts on the beaches along the southern Leizhou Peninsula. Based on the field profile survey and sediment sampling before and after the typhoon landfall, beach response characteristics are investigated in this study. The main results show the following. (1) Under extreme wave conditions, the surface sediment became coarser and the sorting was worse. Beach states transformed toward more dispersed states to buffer and adapt to the high intensity wave energy. (2) Beaches and different segments in the same beach had different responses. These differences were influenced by the headlands, bays’ orientations and sizes. Submarine bar or beach berm may occur on the beach profile. Attention should be paid to the roles of geological and geomorphologic factors when studying beach responses to storms. (3) Changes of the Dengloujiao Beach were influenced by the reef flat and the huge sandy headland. The beach response of beach-coral reef flat system to storm needs further study. More detailed observations and studies of beach responses to storms are needed in the future.