基于多源数据的福建东山岛海岸侵蚀及其不同时空尺度成因分析

摘要

Coastal erosion causes great harm to islands with scarce land resources and beach of tourism value .Based on multi source data such as satellite remote sensing ,aerial photography ,unmanned aerial vehicle(UAV ) ,GPS and field survey etc ,the changes of coastline types ,location ,length and evolution of beach surface erosion in Dongshan Island was analyzed by GIS .The results show that the length of entire coastline was reduced ,because of the trans‐formation from irregular natural coastline to regular artificial coastline .UAV elevation inversion can meet precision requirements for beach surface erosion monitoring .Various breeding drainage ways on beach surface has caused different beach surface gullies in Wujiao Bay and Nanmen Bay ,so the micro morphology of the beach was changed . Rising sea levels and the typhoon storm surge are representative factors of the long term and short term erosion re‐spectively .Present human activities has become the most important factor of coastal erosion in short time scale ,and is likely to turn into long term tendency factor .%海岸侵蚀对海岛紧缺的陆地资源及旅游价值较大的沙滩危害巨大。基于卫星遥感、有人航空摄影、无人机航测、GPS和现场调查等多源数据，利用GIS分析了东山岛海岸线类型、位置与长度变化及滩面冲蚀演变。研究表明，东山岛多处曲折自然岸线转化为较为平直的人工岸线致使整体岸线长度减少，无人机高程反演满足滩面排水冲蚀监测精度要求，乌礁湾和山南湾不同养殖排水方式形成不同特征的滩面冲沟，改变了沙滩微地貌形态。海平面上升和台风风暴潮是长期趋势性和短期突发性侵蚀因素的代表，当前短时间尺度的人类活动已成为滩面冲蚀的最主要因素，且有可能转变为长期趋势性因素。