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Characteristics of Cross Sections and Dynamic Factors of Bed Fomrming in the Lower Tidal Reach of the Yangtze River

  • Xingnong ZhangEmail author
  • Changying Chen
  • Dongdong Jia
Conference paper

Abstract

Based on the measured hydrological and topographic data of the reach below Nanjing of the Yangtze river, and the result of the one-dimensional tidal current numerical model, some issues about hydrodynamic factors of riverbed-forming in the tidal river were discussed. It is shown that the factors in tidal reach of the Yangtze River formed by the interweaving of runoff and tidal current, and the hydrodynamic force along downstream increases continuously due to superposition of runoff and tide. Because of riverbed storage and tidal wave deformation, in addition to the general bend and branching characteristics, the overall trend of channel plane morphology is to gradually broaden to form bell-shaped mouth with an inflection point appearing near the flood tidal current limit, but the average depth of cross-sections is maintained in 10~30m. Specifically, in the upper reach of the dry tidal current limit, runoff plays a major role in riverbed-forming, and the main channel width is 1500~2000m and the dominate discharge is 44000~47000m3/s.In the reach between the dry tidal current limit and the flood tidal current limit, both runoff and tidal current act together to riverbed-forming, and the main channel width is 2000-4000m and the dominate discharge is 50000~55000m3/s. In the lower reach of the flood tidal current limit, tidal current plays a major role in riverbed-forming, and the main channel width is 4000-13000m and the dominate discharge is greater than 75000 m3/s.

Keywords

the tidal reach of the Yangtze river cross sections dynamic factors 

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Notes

Acknowledgements

The authors gratefully acknowledge the support of the National Natural Science Foundation of China (No: 51679147,51779148 & 51579151) and the National Key R&D Program of China (No: 2018YFC0407302).

References

  1. Biedenharn D S, Thorne C R, and Watson C C(2000). Recent morphological evolution of the Lower Mississippi River. J. Gemorphology. (34):227-249.CrossRefGoogle Scholar
  2. DOU Guo-ren(1964). Riverbed morphology of alluvial plains rivers and tidal estuaries. J. Journal of Hydraulic Engineering. (2): 1-13. (in Chinese)Google Scholar
  3. HOU Chengcheng, ZHU Jianrong(2013). Study on the quantitative relationship of the location of the tidal current limit and the river discharge in the Changjiang Estuary. J. Journal of East China Normal University(Natural Science). (5):18-26. (in Chinese)Google Scholar
  4. LI Jianyong(2007). Study on water and sediment characteristics and fluvial process of the Datong-Xuliujing reach in the lower Yangtze River. Ph.D. Thesis, Hohai Univ. Nanjing, China. (in Chinese)Google Scholar
  5. O’BREIN M P.(1931). Estuary tidal prisms related to entrance areas. J. Civil Engineering. Serial No.1(8): 738-739.Google Scholar
  6. Rich A, Keller E A(2013). A hydrologic and geomorphic model of estuary breaching and closure. J]. Geomorphology. (191) :64·74.Google Scholar
  7. WU Daowen, WANG Xiudan, WANG Xiaojun(2013). Calculation of dominant discharges in the Yangtze Estuary. Proc. of the 16th China ocean (shore) engineering symposium. China ocean engineering society. Dalian, China. Dalian:1307-1314.(in Chinese)Google Scholar
  8. XU Hanxing, FAN Lianfa, GU Mingjie(2012). On tidal mark and tidal current mark in the Yangtze River s. J. Port & Waterway Engineering. Serial No.467 (6):15-20. (in Chinese)Google Scholar
  9. YANG Yunping, LI Yitian, HAN Jianqiao, et al(2012). Variation of tide limit and tidal current limit in Yangtze Estuary and its impact on projects. J. Journal of Sediment Research. (6):46-51. (in Chinese)Google Scholar
  10. YUN Caixing(2004). The recent evolution of the Yangtze river estuary. M. China Ocean Press. Beijing, China. (in Chinese)Google Scholar
  11. ZHANG Wei, XU Jingxin(2017). Study on dominant discharges in the tidal reach of the lower Yangtze River. J. Port&Waterway Engineering. SeriaI No.527 (4): 8-14.(in Chinese)Google Scholar
  12. ZHANG Xingnong, CHEN Zhangying, LIU Hui(2012). Studying on dividing and connecting of the hydrology standard between river and sea navigation engineering. J. ADVEANCE IN WATER SCIENCE. 26(5):717-726. (in Chinese)Google Scholar
  13. ZHAO Zi-hui(2014). Research and application of hydraulic geometry to reach of the Yangtze River. Ph.D. Thesis, Nanjing: Nanjing Normal Univ. (in Chinese)Google Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2020

Authors and Affiliations

  1. 1.Nanjing Hydraulic Research InstituteNanjing CityChina

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