台风"艾利"对福建沙质海滩影响过程研究

通过对福建沙质海滩地形地貌现场调查,对比分析0418号台风“艾利”登陆福建前后各沙滩剖面的蚀淤变化,探讨了福建沙滩对台风“艾利”响应规律。研究结果表明,2004年8月底台风“艾利”过境期间,福建沿海砂质海岸显出了较强烈的地貌响应。沙滩剖面地形变化,冲淤相间,以冲蚀为主;后滨沙丘蚀退、滩肩蚀低、岸线向陆迁移是地貌响应的主要特征;沙滩沉积物的总收支趋于亏损。不同海岸类型的沙滩剖面对台风“艾利”的响应特征不同。岬湾型沙滩剖面地貌响应以前滨滩面侵蚀为主要特征。夷直型的长乐江田下沙剖面,对“艾利”台风的主要地貌响应特征为后滨沙丘、高潮带侵蚀,岸线后退超过16m,出现高度近1 m的直立侵蚀陡坎。沙坝-泻湖型沙滩剖面冲淤变化的主要特征是中潮带形成次一级沙坝。各沙滩的地貌风暴效应有自北往南依次减弱的趋势。

Study on process response of Fujian beach geomorphology to typhoon Aere

On the basis of investigation of the beach geomorphology along the coast of Fujian,the erosion and accretion variation of beach profiles during Aere's landing was compared and analyzed,and the rule of response of the beach to Aere was summarized.The study indicates that violent geomorphology response occurred on beaches during the Aere's landing at the end of August,2004.The landform profiles eroded in general with several sections being aggradated.The backshore dunes' retreating,the berms' lowering,and the shoreline's moving landwards were the main response features of the profiles.The beach sediment budget decreases in the volume.The beach profiles of different coast types responded to Aere differently.The geomorphology response feature of cape-bay coast profiles was erosion in foreshore.The shape of profile changed from berm type to bar type.The straightened beach profile is at Xiasha,Jiangtian and Changle,and its main feature of response to Aere was dunes' erosion in backshore,shoreline recession and beach scarps occurring.The main response feature of the bar-lagoon beach profile was the formation of secondary bars at the mid tide zone.The storm effect on the beaches weakened subsequently from north to south.