| 摘要: |
| 刁口亚三角洲自废弃以来海岸地貌发生了巨大变化, 监测海岸线的变化对于保护和开发海岸带具有重要意义。本文以1976—2021年间典型年份的Landsat遥感影像和Google Earth高分辨率影像为数据源, 通过RS、GIS技术对刁口废弃亚三角洲地区的岸线进行提取, 最后用数字岸线分析系统对1976—2021年间的海岸线变迁进行定量分析。结果显示: 1976—2021年间海岸线以均值–23.24 m/a的速率向陆蚀退, 侵蚀程度逐年减弱, 且海岸线时空变化特征显著。就侵蚀程度而言, 刁口河口及东侧烂泥湾地区侵蚀强度最大(–165.49 m/a), 挑河口—刁口河口岸段次之(–127.61 m/a), 东北侧防海大堤岸段最小(–80.66 m/a)。1976—1986年研究区岸段处于快速侵蚀状态, 蚀退面积达102.7 km2; 1986—2006年处于持续侵蚀后退状态, 蚀退面积约为88.79 km2; 2006—2016年基本达到冲淤平衡状态, 2016年面积和2006年相差不大; 自2016年呈现缓慢蚀退状态, 年均蚀退速率为仅2.51 km2。岸线长度总体上表现为减少趋势, 但在1996年成为最低点后有所增加。刁口废弃亚三角洲海岸线变化主要受入海水沙、人类活动和海洋动力作用侵蚀的影响。 |
| 关键词: 刁口废弃亚三角洲 Landsat 海岸线 数字岸线分析系统 修正归一化水体指数 |
| DOI：10.11759/hykx20220327001 |
| 分类号:P737.12 |
| 基金项目:国家自然科学基金资助项目(41901006); NSFC—山东联合基金资助项目(U1706220); 山东高校青创科技团队项目(2020KJH002); 山东省基金资助项目(ZR2019BD005) |
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| Analysis of coastline changes in the abandoned sub-delta of Diaokou over the past 50 years |
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REN Zong-hai, ZHAN Chao, YU Jian-kui, GENG Wen-qian, CAO Yin, WANG Qing
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Institute of Coastal Research, Ludong University, Yantai 264025, China
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| Abstract: |
| The coastal geomorphology of Diaokou sub-delta has changed dramatically since its abandonment, and monitoring the changes of shoreline is important for the protection and development of the coastal zone. In this paper, Landsat remote sensing images and Google Earth images of typical years between 1976 and 2021 were used as data sources to extract shorelines in the abandoned sub-delta of Diaokou by RS and GIS techniques. Finally, the shoreline changes from 1976 to 2021 were quantitatively analyzed by Digital Shoreline Analysis System (DSAS). The results showed that the shoreline retreated to land with a mean value of –123.24m/a during 1976—2021, and the degree of erosion decreased year by year, and the spatial and temporal variation of shorelines was significant. In terms of erosion intensity, Diaokou River estuary and the eastern ruddy bay have the highest erosion intensity (–165.49 m/a), the Tiaohe River-Diaokou River port section has the second highest (–127.61 m/a), and the northeastern coast defense dike section has the lowest (–80.66 m/a). From 1976 to 1986, the shoreline of the study area was rapidly erosion, with an erosion area of 102.7 km2; from 1986 to 2006, it was in a state of continuous erosion and retreat, with an erosion area of 88.79 km2; from 2006 to 2016, it basically reached a state of equilibrium between erosion and siltation, and the area in 2016 was not much different from that in 2006; since 2016, it has been in a state of slow erosion and retreat. The overall trend of shoreline length is decreasing, but it has increased after the lowest in 1996. The shoreline changes of the abandoned delta of Diaokou are mainly influenced by river water and sediment, human activities and ocean dynamics. |
| Key words: Diaokou abandoned sub-delta Landsat shoreline DSAS MNDWI |
