摘要
针对河口泥沙岛淤泥质潮滩坡度和潮汐变化对水边线的影响,提出一种利用两期遥感水边线模拟海岛岸线及潮滩数字高程模型(Digtal Elevation Model,DEM)的方法,研究辽河口鸳鸯岛的形成与演变过程。结合遥感影像、实测地形和潮位数据分析表明:1)模拟潮滩DEM与实测DEM之间的误差集中在—40~55cm的范围内,平均误差14.24cm,表明遥感模拟作为一种手段对实测资料的欠缺是一种有效的补充。2)从20世纪80年代初至今,鸳鸯岛的发育经历了萌生、生长和动态稳定三个时期;入海径流量的增加是鸳鸯岛萌生的诱因,涨落潮流路分歧及其形成的缓流区促进鸳鸯岛的持续生长。3)在鸳鸯岛生长过程中,南沙处在次生缓流区中,在相同时段内其潮滩淤积量大于北沙;在鸳鸯岛演变稳定期,就岸线和面积变化而言,东北部潮滩侵蚀程度小于南部潮滩淤积程度,但从体积变化来看,东北部潮滩侵蚀量略大于南部潮滩淤积量。
Tidal and landform variations have a significant impact on detection of coastline changes for a tidal flat of estuary island dominated by sediment deposits.In thisstudy,we presented a methodology that simulate the shoreline of island and the Digtal Elevation Model（DEM）of tidal flat,and studied the formation and evolution of Yuanyang Island in Liaohe Estuary.Combined with remote sensing images,the measured topography and tidal data analysis show that,1）The error between DEM and practical tidal flat varies from-40 cm to 55 cm,with the average value of 14.24 cm,which imply that remote sensing modeling can be an effective supplementary way under the case of the scarcity ofthe measured data.2）From the1980 sto present,the development of Yuanyang Island can be divided into the following three periods,initiating,growth and dynamic stablingstages.The increase of river discharge led to the initiation of the formation of Yuanyang Island.The different routines of flood flow and ebb flow,together with the slow water area between these two channels,promote the growth of this island.3）During the growing period of Yuanyang Island,South Bar is in the second slow water area and its tidal flat sedimentation rate is greater relative to North Bar.During the stable period of Yuanyang Island,in terms of the variations of coastline and area changing,the erosion degree of tidal flat in the northeast tidal flat is less thanthe deposition degree of the tidal flat in the southern tidal flat.However,from the point of view of volume variations,the erosion amount of the northeast tidal flat is slightly larger than the deposition amount of the southern tidal flat.
出处
《海洋科学进展》
CAS
CSCD
北大核心
2017年第4期579-592,共14页
Advances in Marine Science
基金
海洋公益性行业科研专项--典型海岛生态脆弱性评估及综合调控技术研究与示范(201505012)
关键词
水边线方法
潮位校正
河口泥沙岛
冲淤演变
waterline apprpach
tide correction
estuary sediment island
evolution of erosion and deposition
