海南岛峨蔓五彩湾内海蚀平台对海蚀崖侵蚀的影响研究  

A study of the effect of shore platform morphology on coastal erosion of rocky cliffs in the Wucaiwan Bay,E’man,Hainan Island

作　　者：赵中伟 吴凌云 高伟健 李伟[1,2,3] ZHAO Zhongwei;WU Lingyun;GAO Weijian;LI Wei(CAS Key Laboratory of Ocean and Marginal Sea Geology(South China Sea Institute of Oceanology,Chinese Academy of Sciences),Guangzhou 511458,China;Sanya Institute of Ocean Eco-Environmental Engineering,Sanya 572000,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院边缘海与大洋地质重点实验室(中国科学院南海海洋研究所),广东广州511458 [2]三亚海洋生态环境工程研究院,海南三亚572000 [3]中国科学院大学,北京100049

出　　处：《热带海洋学报》2024年第5期106-115,共10页Journal of Tropical Oceanography

基　　金：国家自然科学基金项目(42206216);海南省自然科学基金项目(421QN0978)。

摘　　要：全球海洋变化所引起的极端波浪海洋灾害趋强,势必会加剧海南岛的海蚀崖侵蚀地质灾害危险。海蚀平台能够有效衰减波浪能量,从而降低极端波浪对海蚀崖的侵蚀破坏。海南岛西北部的火山岩基岩海岸地区,存在大量海蚀平台地貌,是研究海蚀平台对海蚀崖侵蚀影响的理想地区。文章以海南岛儋州市峨蔓镇的五彩湾基岩海岸为研究对象,利用海洋遥感影像刻画了五彩湾海蚀崖近十年的平均侵蚀速率达0.26m·a^(−1),通过物理海洋分析方法预测了研究区未来100年回归周期可能遭受的最大波高达7.8m,进一步基于海岸地貌研究方法调查了五彩湾倾斜型海蚀平台的地貌特征,及其后部海蚀崖岩石的抗侵蚀强度,从而通过数值计算证明了海蚀平台可以使得未来极端波浪对五彩湾海蚀崖的侵蚀强度平均减缓80%以上。此外,文章进一步探讨了五彩湾海蚀崖底部沉积沙滩、崖底植被和海蚀崖滑塌堆积物的天然护岸作用。The intensification of extreme wave marine hazard induced by global ocean change is very likely to accelerate the geohazard risk of cliff erosion in Hainan Island.Shore platforms are expected to effectively attenuate wave energy approaching the shore and consequently reduce the erosive impact of extreme waves on cliff.Shore platforms are commonly observed in volcanic rocky coasts on NW Hainan Island,providing an ideal natural laboratory to evaluate the effect of shore platform morphology on cliff erosion.This study employs the Wucaiwan Bay rocky coastline in the E’man Town,Danzhou City,Hainan Island as the study area.Time-lapsed marine remote sensing images revealed the cliff erosion rate is about 0.26 m·a^(−1) in the last decade in the area.Physical oceanography analysis suggested a maximum significant wave height of 7.8 m could be expected visiting the area in a 100-years return level.The geomorphological characteristics of the sloping shore platform and the rock strength of cliffs were further surveyed via coastal geomorphological approaches.Numerical computation outputs suggest the shore platforms is capable of reducing the wave erosional forces on cliff by over 80%under future extreme wave conditions.This study further discusses the natural coastal protection from sediment beaches,vegetations and in situ deposition of eroded boulders at rock cliff foot.

关 键 词：海蚀平台 海蚀崖侵蚀 玄武岩海岸 数值计算 海南岛 

分 类 号：P737.13[天文地球—海洋地质]