地理学报 ›› 1993, Vol. 60 ›› Issue (6): 516-526.doi: 10.11821/xb199306005

• 论文 • 上一篇    下一篇

海平面上升对长江三角洲和苏北滨海平原海岸侵蚀的可能影响

季子修, 蒋自巽, 朱季文, 杨桂山   

  1. 中国科学院南京地理与湖泊研究所,南京 210008
  • 出版日期:1993-11-15 发布日期:1993-11-15
  • 基金资助:
    国家自然科学基金重大项目(编号:948807);中国科学院重大项目(编号:87-45-03)的研究成果之一

IMPACTS OF SEA LEVEL RISE ON COASTAL EROSION IN THE CHANGJIANG DELTA AND NORTH JIANGSU COASTAL PLAIN

Ji Zixiu, Jiang Zixun, Zhu Jiwen, Yang Guishan   

  1. Nanjing Institute of Geography & Limnology, Academia Sinica, Nanjing 210008
  • Online:1993-11-15 Published:1993-11-15

摘要: 本区海岸现有30%的岸段为侵蚀海岸,海平面上升将使海岸侵蚀加剧。海平面上升因素在海岸侵蚀诸因素中的比重较国外同类研究结论偏小,这与本区海岸的特殊演变原因有关。海平面上升通过潮流、波浪和风暴潮作用增强,海岸潮滩和湿地损失,岸滩消浪和抗冲能力减小等途径引起海岸侵蚀加剧。其结果是,侵蚀岸段扩大,淤涨岸段减少甚至转为侵蚀,潮间带宽度变窄,坡度加大,从而使沿岸海堤等挡潮工程的标准要相应提高。

关键词: 海岸侵蚀, Bruun定律, 海平面上升

Abstract: At present,approximately 30% of coasts are experiencing net erosion in the Changjiang Delta and the North Jiangsu coastal plain. Future sea level rise will accelerate the process of coastal erosion. According to the ratio of the calculated value of coast retreat by Bruun rule to the estimated value by using measured data,the proportion affected by sea level rise in total coastal erosion has been estimated in this paper. When sea level rises 20cm,the proportion determined by sea level rise will increase from 1.0% at present to 2. 2%in the future in the coasts of the Abandoned Yellow River Delta and from 8. 5%一9. 6%to l 3. 5%一15. 2%in the north and south coasts of the Changjiang Delta. This result is lower than that from the similar research in the world,and this phenomenon is related with the special development process of the coasts in this area. In the coasts of the Abandoned Yellow River Delta,coastal erosion is due to the sediments deficiency since the Yellow River returned to its north route in 1855,but in the coasts of the Changjiang Delta,there are rich in sediments,coastal erosion is mainly due to strong hydrodynamic action. Judged by the range of near-future sea level rise,sea level rise will not become a controlled factor of coastal erosion in this area. The mechanism of accelerating coastal erosion by sea level rise is that sea level rise will increase the intensity of tidal current,wave and storm surge and decrease the ability to reduce the force of waves on the tidal flat and coastal wetland due to the loss of their areas. Therefore ,the length of erosion coasts will increase,the sedimentation rate of accretion coasts will decrease or even turn accretion into erosion,the width of tidal flat will reduce and coastal slope will increase. So the project of coastal protection of this area must be reinforced.

Key words: coastal erosion, Bruun rule, sea level rise