1973—2016年南黄海辐射沙脊群东沙动态演化分析  

Dynamic evolution of Dongsha shoal of the radial sand ridges in the South Yellow Sea from 1973 to 2016

作　　者：刘柄麟 张振克[1] 何华春[1] 任航[1] 王卿 汪欢[1] LIU Binglin;ZHANG Zhenke;HE Huachun;REN Hang;WANG Qing;WANG Huan(Department of Geographic Information Science, Nanjing University, Nanjing 210023, China)

机构地区：[1]南京大学地理与海洋科学学院,南京210023

出　　处：《海洋地质与第四纪地质》2018年第2期63-71,共9页Marine Geology & Quaternary Geology

基　　金：国家自然科学基金项目"辐射沙洲群典型区域短尺度沉积与地貌过程研究"(41371024);"江苏沿海滩涂围垦土地质量变化过程及生态安全响应"(41230751);科技部科技支撑项目子课题"沿海滩涂农地生态化开发关键技术和示范"(2012BAC07B01)

摘　　要：以江苏岸外辐射沙洲地区的东沙为例,基于1973—2016年长周期遥感影像,引入形态学中最小外接矩形与质心的概念,对沙洲整体运动趋势进行研究。通过ArcGIS10.2软件提取各时相的东沙滩最小外接矩形质心,对不同时期的质心进行比较,以确定东沙滩在不同时期的整体运动趋势,同时通过热带气旋与东沙滩紫菜养殖资料进一步分析东沙滩运动的影响因素。研究发现:东沙滩在43a间的总体运动方向为北东北,具体分为5个阶段,各阶段运动方向与速度有所不同;东沙滩运动对热带气旋的响应有越来越强的趋势;近期快速扩张的东沙滩紫菜养殖对东沙的泥沙沉积的影响还有待进一步研究。The Dongsha Shoal,apart of the radial sand ridges off the Jiangsu coast,is selected as a case in this paper to study the dynamic evolution of the ridge system.Based on the remote sensing images from1973 to 2016,the concepts of minimum enclosing rectangle and centroid in morphology are introduced to reveal the general moving trend of the shoal.The centroids of minimum enclosing rectangles of each phase are extracted by means of ArcGIS10.2.The general moving trend of the Dongsha Shoal is specified by comparison of the centroids in different stages.The factors affecting the movement of Dongsha shoal is further studied with the data of nori-planting and records of tropical cyclones.The results suggest that the Dongsha Shoal has been moving toward north and northeast in the past 43 years.It can be further divided into five specific phases.The moving directions and speeds in each phases are different.Data shows that the impact of tropic cyclones is increasing in the Dongshan Shoal.The nori-planting in Dongsha Shoal expands currently,of which the impacts on the sand sediment at the Dongsha Shoal requires further researches.

关 键 词：最小外接矩形 质心 动态 动力机制 东沙滩 

分 类 号：P737.1[天文地球—海洋地质]