人工养护后厦门香山-长尾礁海滩的演变特征  

Evolution characteristics of nourished beach from Xiangshan to Changweijiao in Xiamen

作　　者：曹惠美[1] 蔡锋[2] 郑勇玲[1] 

机构地区：[1]国家海洋局第三海洋研究所,福建厦门361005 [2]国家海洋局海岛研究中心,福建平潭350403

出　　处：《应用海洋学学报》2015年第1期24-33,共10页Journal of Applied Oceanography

基　　金：福建省自然科学基金资助项目(2009J01219);国家海洋局海洋沉积与环境地质重点实验室开放基金资助项目(MASEG200612);国家海洋局第三海洋研究所基本科研业务费专项经费资助项目(海三科2009060)

摘　　要：通过对厦门香山-长尾礁养护后海滩的地形地貌和沉积物的变化进行研究,分析了养护后海滩的演变特征,发现该海滩养护后第一年内海滩平面和剖面变化最剧烈,滩肩外缘线和0 m线蚀退量最大,滩肩外缘线平均蚀退20.0 m,最大蚀退量达30.0 m,0 m线平均蚀退8.0 m,最大蚀退量达12.8 m,海滩滩面变陡,坡度从初始的3.5°变成了6.4°,滩面沉积物从0.30~0.66 mm变粗到1.46mm,之后趋于一个相对稳定的态势.应用经验正交函数（EOF）提取香山-长尾礁海滩自2009年4月至2014年3月竣工后60个月内15次的剖面监测数据中的主要空间模态和时间模态信息来分析海滩剖面的时空变化特征,结果表明该海滩有两个主要模态,第一模态是滩肩剖面和沙坝剖面的转换,其贡献率为77.72%,第二模态表现为大潮高潮位的侵蚀性滩角,该模态贡献率为13.53%.采用GSTA模型进行泥沙净运移趋势分析,结果显示该海滩泥沙总体上呈向岸运移的趋势,说明近年来养护后的海滩基本处于稳定状态.海滩养护5a后,后滨填沙保存88%,养护后的海滩形态与预期的形态相近,养滩效果良好.Based on the study of variations of geomorphology and sediment distribution of the nourished beach from Xiangshan to Changweijiao in Xiamen,a project performance is analyzed in thespaper. It shows that the beach planform and profiles changed dramatically after being nourished within the first year. The berm and the zero meter line eroded,averagely 20. 0 m and 8. 0 m,at the most and the largest one reached 30. 0m and 12. 8 m,respectively. The beach face gradient steepened from 3. 5° to 6. 4°. The grain size of beach face coarsen from 0. 30 ~0. 66 mm to 1. 46 mm. Thereafter,it would present a new balanced planform. Empirical Orthogonal Function is applied to pick up spatial mode and temporal mode to analyze beach profiles measured at Xiangshan-Changweijiao from April 2009 to March 2014. It indicates that the beach profile variation includes 2 modes. The first complex mode contributing to the variance of the data is 77. 72 % which represents the step beach interconvert the bar beach. The second complex mode contributing to the variance of the data is 13. 53 % which represents the beach cusps erupted at spring high tide. According to the analysis on the net transportation trend of the grain size parameter by Gao,the sediment of the beach transported on the shore is large. Five year after the nourishment,88% of the filling sands were remained at the backshore and the beach geomorphology was similar to the expectation. As a whole,the beach nourishment was rather successful.

关 键 词：海洋地质学 人造沙滩 经验正交函数 空间模态 时间模态 运移趋势 演变 厦门 香山-长尾礁 

分 类 号：P736[天文地球—海洋地质]