华南海岸风沙地貌台风响应模式的典型研究

Based on the pre-and post-typhoon high-precision surveys of shape change of different types of coastal Aeolian landforms, fixed position observation of wind-sand processes in the season of non-typhoon time and systematic sampling analysis of Aeolian deposit sediments over coastal dunes at the coasts of Pingtan Island in Fujian Province which is one of the most typical distribution areas in China, the pre-and post-typhoon change of the position and shape as well as the size of coastal dune and the volume of erosion and accumulation over coastal dune are compared with the different coast area, different coastal dune types, different protection status of coastal dunes, and different intensity and wind direction of typhoons, so as to the pre-and post-typhoon change of the structure and thickness of Aeolian deposit sediment stratifications and the particle size of Aeolian deposit sediments. The difference of morphological and sedimentological impacts of typhoon to different coastal Aeolian landforms is researched, in which the relationship between the typhoon and the change of shape and deposit sediment of coastal Aeolian landforms in typical area is quantitative analyzed, the basic rule of typhoon effect of coastal Aeolian landforms in south China is explored and the models of typhoon effect of coastal Aeolian landforms in south China are established. This is the first systematic research on the typhoon effect of coastal Aeolian landforms in China. This research has the characteristics of leading subject, filling gaps in studying and the systematic and actual field measurement study. There would be some progresses achieved in the quantitative analysis of influence factors of the models of typhoon effect of coastal Aeolian landforms. Through this project, the status of coastal Aeolian landform research continuing to use the normal research form of inland Aeolian landform research will be broken in China. This project will make important intention to improve the research level of coastal Aeolian landforms in China, which has profound scientific and practice significance.

通过对台风前后不同类型海岸沙丘形态变化的高精度测量、非台风季风沙运动过程的定位观测以及沙丘沉积物的系统采样分析等，比较研究区域不同的海岸地点、沙丘类型、海岸防护状态及不同强度和风向的台风作用下，海岸沙丘台风前后的位置、形态、规模及不同部位侵蚀与堆积量的变化，海岸沙丘表面沉积层层理结构、厚度与沉积物粒度的变化，研究海岸风沙地貌形态与沉积物对台风响应及其差异性，定量分析海岸风沙地貌形态和沉积变化与台风间的相互联系，探究台风对华南海岸风沙地貌的作用规律，建立华南海岸风沙地貌的台风响应模式。该研究是对我国海岸风沙地貌台风响应的首次系统研究，具有学科前沿、填补空白、系统与实测性研究的特点，并将在定量分析海岸风沙地貌台风响应模式的影响因素方面取得一定进展，是突破沿用内陆风沙地貌研究范式进行海岸风沙地貌研究的一项重要工作，对提高我国海岸风沙地貌研究水平将产生重要作用，具有重要的科学意义与实践价值。

项目按计划完成了研究设计、研究区域选择、数据资料收集、定位半定位观测点设定、野外实地调查观测与测量、室内样品分析、数据整理、理论分析总结与成果发表等工作，具体选择福建平潭岛海岸为典型研究区域，采集了16659个海岸沙丘高精度测量数据、5539个海岸沙丘表层粒度样品数据和一次海岸沙丘野外风沙观测数据，在华南海岸不同类型沙丘形态的台风响应、不同类型沙丘表层沉积物的台风响应、不同海岸沙丘台风响应的差异性以及华南海岸风沙地貌台风响应机理等方面取得了较好的研究成果。研究结果表明，海岸沙丘在台风登陆前后的形态变化主要是以体积减少和沙丘高度降低为主但不同类型海岸沙丘及其不同部位的响应并非一致且存在较大差异，不同类型海岸沙丘在台风群登陆前后的形态变化存在一定差异且不同类型海岸沙丘形态对台风群的响应中均未见累积效应，整体而言海岸沙丘表层粒度对台风的响应变化不明显、基本无等级性质的差别，得出了整体而言台风对海岸沙丘的影响应是暂时和局部性的，较长时间尺度而言低频高能的台风对海岸沙丘形态和表层沉积物粒度的塑造与影响相对有限，但不同类型海岸沙丘对台风的响应存在一定差异等一些研究结论。项目研究结果，是国内海岸风沙地貌台风响应模式研究的重要进展，填补了我国该方面的研究空白，丰富了我国海岸风沙研究的内容、理论与方法，具有较为重要的科学意义与实践价值。