地理学报 ›› 2007, Vol. 62 ›› Issue (7): 707-716.doi: 10.11821/xb200707004

• 地貌演化 • 上一篇    下一篇

近10 年来长江口水下三角洲的冲淤变化 ———兼论三峡工程蓄水的影响

李鹏1,2, 杨世伦1, 戴仕宝3, 张文祥1   

  1. 1. 华东师范大学河口海岸学国家重点实验室, 上海200062;
    2. 国家海洋局东海预报中心, 上海200081;
    3. 滁州学院地理系, 安徽滁州239012
  • 收稿日期:2006-11-03 修回日期:2007-05-10 出版日期:2007-07-25 发布日期:2010-08-04
  • 通讯作者: 杨世伦, 教授, E-mail: slyang@sklec.ecnu.edu.cn E-mail:slyang@sklec.ecnu.edu.cn
  • 作者简介:李鹏(1978- ), 男, 山东菏泽人, 博士生, 主要从事河口海岸环境研究。E-mail: lipeng827@126.com
  • 基金资助:

    国家自然科学基金项目(40576043); 教育部创新团队发展计划项目(PCSIRT0427); 上海市科委重大项目 (04DZ19305); 国家重大基础研究发展规划(973)项目课题(2002CB412407)

Accr etion/erosion of the Subaqueous Delta at the Yangtze Estuary in Recent 10 Year s

LI Peng1,2, YANG Shilun1, DAI Shibao3, ZHANG Wenxiang1   

  1. 1. State Key Lab of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China;
    2. East China Sea Forecast Centre, SOA, Shanghai 200081, China;
    3. Geography Department, Chuzhou University, Chuzhou 239012, Anhui, China
  • Received:2006-11-03 Revised:2007-05-10 Online:2007-07-25 Published:2010-08-04
  • Supported by:

    National Natural Science Foundation of China, No.40576043; Program for Innovative Research Team in University, Ministry of Education, No.PCSIRT0427; Shanghai Science and Technology Committee, No.04DZ19305; National 973 Project, No.2002CB412407

摘要:

根据对近10 年来长江入海泥沙量和河口冲淤的对比分析, 探讨水下三角洲冲淤对长江入海泥沙锐减以及三峡工程运行的响应。结果表明: (1) 三峡水库蓄水导致长江入海泥沙减少1×108 t/a 量级; (2) 1995-2000 年、2000-2004 年和2004-2005 年研究区淤积(冲刷) 面积分别占75.5% (24.5%)、30.5% (69.5%) 和14% (86%), 垂向冲淤速率(负为冲刷) 分别为6.4 cm/a、-3.8 cm/a 和-21 cm/a。(3) 由于地形和水动力的变化以及工程的影响, 研究区内冲淤对河流来沙减少的响应存在显著空间差异。结论包括: 三峡水库蓄水加剧了长江入海泥沙的减少; 入海泥沙的锐减是水下三角洲从淤积为主向侵蚀为主转变的主要原因。随着水库拦沙能力的增强等流域人类活动的影响, 长江入海泥沙将进一步下降, 河口口门区的冲刷可能加剧, 值得有关部门重视。

关键词: 长江, 三峡工程, 水下三角洲, 冲淤演变

Abstract:

Based on the sediment supply from the Yangtze River and the analysis of the accretion/erosion of the subaqueous delta at the Yangtze Estuary in recent ten years, the accretion/erosion response of the subaqueous delta to the sharp decline of the sediment supply from the Yangtze River to the sea and the impoundment of the Three Gorges Reservoir was preliminarily discussed. The results show that (1) because of the impoundment of the Three Gorges Reservoir, the sediment supply from the Yangtze River to the sea decreased at an order of magnitude 1×108 t/a; (2) the proportion of accretion area to the total area is 75.5%, 30.5% and 14% in the three periods. The accretion/erosion rates of the three periods (1995-2000, 2000-2004, 2004-2005) are 6.4 cm/a, -3.8 cm/a and -21 cm/a respectively in the study area; and (3) the accretion/erosion response to the decrease of the sediment discharge from the Yangtze River in the study area has significant spacial different results in the influence of topography, the change of hydrodynamics and the engineering projects. The conclusions are that the impoundment of the Three Gorges Reservoir accelerated the decrease of the sediment from the Yangtze River which is the main cause for the change from accretion to erosion of the subaqueous delta. Attentions should be paid to the future evolution processes of the Yangtze River Delta in view of the further decrease of sediment supply of the Yangtze River, which is due to the more dam construction and land conservation in the future, and the consequent further erosion in the subaqueous delta.

Key words: the Yangtze River, the Three Gorges Reservoir, subaqueous delta, the analysis of accretion/erosion