河口区斜压梯度对余水位的累积影响及其机制探讨

杨昊; 欧素英; 姚鹏; 郭晓娟; 杨清书; 蔡华阳

doi:10.3969/j.issn.0253-4193.2019.01.003

河口区斜压梯度对余水位的累积影响及其机制探讨

doi: 10.3969/j.issn.0253-4193.2019.01.003

中山大学海洋工程与技术学院河口海岸研究所, 广东广州 510275;河口水利技术国家地方联合工程实验室, 广东广州 510275

基金项目: 国家重点研发计划（2016YFC0402600）；国家自然科学基金项目（51709287，41106015，41476073）；广东省自然科学基金（2017A030310321）；高校基本科研业务费青年教师重点培育项目（17lgzd12）。

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出版历程
- 收稿日期: 2017-11-25
- 修回日期: 2018-07-11

Cumulative effect of baroclinic gradient on the residual water level in estuaries and its underlying mechanism

Institute of Estuarine and Coastal Research, School of Marine Engineering and Technology, Sun Yat-sen University, Guangzhou 510275, China;State and Local Joint Engineering Laboratory of Estuarine Hydraulic Technology, Guangzhou 510275, China

摘要

摘要: 余水位（即潮平均水位）是河口区径潮相互作用的典型结果，研究其形成演变机制对探讨河口区的水资源高效开发利用具有重要科学意义。本文基于不同径潮边界条件下的三维斜压水动力数值模拟及切比雪夫机制分解，初步探讨了概化地形条件下斜压梯度对余水位沿程变化的影响。数值模拟结果表明：河口区余水位的沿程变化明显受径流量、潮波振幅、辐聚地形及斜压梯度等因素的共同影响，斜压梯度对余水位的影响是一种累积效应且影响区域集中在回水区，同时其影响强度具有明显的大小潮变化、洪枯季变化。利用数值模型提供的水位及流速场信息，通过切比雪夫分解非线性摩擦项分离出控制余水位变化的3个主要因素，即径流、潮流和径潮相互作用因子，并与斜压梯度产生的余水位进行对比分析，结果表明：回水区域余水位主要以径潮相互作用因子为主导；斜压梯度对余水位影响主要体现在小潮期间，有可能成为影响余水位变化的主控因子。
- 概化地形 /
- 余水位 /
- 斜压梯度 /
- 切比雪夫分解 /
- 数值模拟
Abstract: Residual water level (i.e. the tidally averaged water level) is mainly controlled by the tide-river interaction, and understanding its formation and evolution is important with regard to water resources management in estuaries. In this study, based on the three-dimensional baroclinic hydrodynamic numerical results under different tide-river conditions and the Chebyshev polynomial decomposition approach, the impact of the baroclinic gradient on residual water level variation was explored for given idealized geometry with a convergent width and a linear bed slope. Model results show that the variation of residual water level along the estuary axis is determined by freshwater discharge, tidal amplitude, convergent topography and baroclinic gradient. In particular, the influence of the baroclinic gradient on the residual water level is featured by an accumulative effect over the whole backwater zone, with a significant spring-neap and wet-dry changes. Information of water level and velocity field are provided by numerical model, making use of Chebyshev polynomial decomposition, it is possible to decompose the residual water level into different components, linking to tide, river and tide-river interaction, respectively. When compared with the residual water level induced by baroclinic gradient, it is shown that, the residual water level in backwater zone is primarily controlled by the tide-river interaction. Effect of baroclinic gradient on the residual water level becomes important during the neap tide and may become the dominant factor on the residual water level.
- idealized geometry /
- residual water level /
- baroclinic gradient /
- Chebyshev polynomial decomposition /
- numerical simulation

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参考文献(29)

欧素英, 杨清书. 珠江三角洲网河区径流潮流相互作用分析[J]. 海洋学报, 2004, 26(1):125-131. Ou Suying, Yang Qingshu. Interaction of fluctuating river flow with a barotropic tide in river network of the Zhujiang Delta[J]. Haiyang Xuebao, 2004, 26(1):125-131.

韩志远, 田向平, 欧素英. 人类活动对磨刀门水道河床地形和潮汐动力的影响[J]. 地理科学, 2010, 30(4):582-587. Han Zhiyuan, Tian Xiangping, Ou Suying. Impacts of large-scale human activities on riverbed morphology and tidal dynamics at Modaomen estuary[J]. Scientia Geographica Sinica, 2010, 30(4):582-587.

路川藤, 罗小峰, 韩玉芳. 长江口洪水期潮波变形数值模拟研究[J]. 海洋工程, 2015, 33(1):73-82. Lu Chuanteng, Luo Xiaofeng, Han Yufang. Numerical simulation study on tidal wave deformation mechanism during flood period in Yangtze estuary[J]. The Ocean Engineering, 2015, 33(1):73-82.

Guo Leicheng, van der Wegen M, Jay D A, et al. River-tide dynamics:exploration of nonstationary and nonlinear tidal behavior in the Yangtze River estuary[J]. Journal of Geophysical Research:Oceans, 2015, 120(5):3499-3521.

欧素英, 田枫, 郭晓娟, 等. 珠江三角洲径潮相互作用下潮能的传播和衰减[J]. 海洋学报, 2016, 38(12):1-10. Ou Suying, Tian Feng, Guo Xiaojuan, et al. Propagation and damping of tidal energy in the Pearl River Delta[J]. Haiyang Xuebao, 2016, 38(12):1-10.

Alebregtse N C, de Swart H E. Effect of river discharge and geometry on tides and net water transport in an estuarine network, an idealized model applied to the Yangtze Estuary[J]. Continental Shelf Research, 2016, 123:29-49.

Lamb M P, Nittrouer J A, Mohrig D, et al. Backwater and river plume controls on scour upstream of river mouths:implications for fluvio-deltaic morphodynamics[J]. Journal of Geophysical Research:Atmospheres, 2012, 117(F1):F01002.

Sassi M G, Hoitink A J F. River flow controls on tides and tide-mean water level profiles in a tidal freshwater river[J]. Journal of Geophysical Research:Oceans, 2013, 118(9):4139-4151.

路川藤, 罗小峰, 陈志昌. 长江潮流界对径流、潮差变化的响应研究[J]. 武汉大学学报:工学版, 2016, 49(2):201-205. Lu Chuanteng, Luo Xiaofeng, Chen Zhichang. Study of current Limit causing by runoff and tidal range in Yangtze River[J]. Engineering Journal of Wuhan University, 2016, 49(2):201-205.

侯成程. 长江潮流界和潮区界以及河口盐水入侵对径流变化响应的数值研究[D]. 上海:华东师范大学, 2013. Hou Chengcheng. Numerical study on the tidal current limit and tidal limit in the Changjiang River and the Response of saltwater intrusion in the Changjiang Estuary to the river discharge change[D]. Shanghai:East China Normal University, 2013.

Bezerra M O M, Pontes R K D S, Gallo M N, et al. Forcing and mixing processes in the Amazon estuary:a study case[J]. IL Nuovo Cimento C, 2008, 31(5):743-756.

Qiu Cheng, Zhu Jianrong. Influence of seasonal runoff regulation by the Three Gorges Reservoir on saltwater intrusion in the Changjiang River Estuary[J]. Continental Shelf Research, 2013, 71:16-26.

Yuan Rui, Wu Hui, Zhu Jianrong, et al. The response time of the Changjiang plume to river discharge in summer[J]. Journal of Marine Systems, 2016, 154:82-92.

Buschman F A, Hoitink A J F, van der Vegt M, et al. Subtidal water level variation controlled by river flow and tides[J]. Water Resources Research, 2009, 45(10):W10420.

Cai H, Savenije H H G, Toffolon M. Linking the river to the estuary:influence of river discharge on tidal damping[J]. Hydrology and Earth System Sciences, 2014, 18(1):287-304.

Cai H, Savenije H H G, Jiang C. Analytical approach for predicting fresh water discharge in an estuary based on tidal water level observations[J]. Hydrology and Earth System Sciences Discussions, 2014, 11(6):7053-7087.

Cai Huayang, Savenije H H G, Jiang Chenjuan, et al. Analytical approach for determining the mean water level profile in an estuary with substantial fresh water discharge[J]. Hydrology and Earth System Sciences, 2016, 20(3):1177-1195.

Cheng Peng, de Swart H E, Valle-Levinson A. Role of asymmetric tidal mixing in the subtidal dynamics of narrow estuaries[J]. Journal of Geophysical Research:Oceans, 2013, 118(5):2623-2639.

韩志远, 田向平, 刘峰. 珠江磨刀门水道咸潮上溯加剧的原因[J]. 海洋学研究, 2010, 28(2):52-59. Han Zhiyuan, Tian Xiangping, Liu Feng. Study on the causes of intensified saline water intrusion into Modaomen Estuary of the Zhujiang River in recent years[J]. Journal of Marine Sciences, 2010, 28(2):52-59.

王彪. 珠江河口盐水入侵[D]. 上海:华东师范大学, 2011. Wang Biao. Salt intrusion in the Pearl River estuary[D]. Shanghai:East China Normal University, 2011.

吕紫君, 冯佳佳, 郜新宇, 等. 磨刀门河口环流与咸淡水混合层化机制[J]. 水科学进展, 2017, 28(6):908-921. Lyu Zijun, Feng Jiajia, Gao Xinyu, et al. Estuarine circulation and mechanism of mixing and stratification in the Modaomen estuary[J]. Advances in Water Science, 2017, 28(6):908-921.

Chao Yi, Farrara J D, Zhang Hongchun, et al. Development, implementation, and validation of a modeling system for the San Francisco Bay and Estuary[J]. Estuarine, Coastal and Shelf Science, 2017, 194:40-56.

Grashorn S, Stanev E V, Koch W, et al. Downscaling to study wave-current interactions in coastal areas:unstructured grid model simulations in the North and Baltic Seas during a storm surge event[C]//Proceedings of EGU General Assembly Conference. Vienna, Austria:EGU General Assembly, 2015.

Savenije H H G. Salinity and tides in alluvial estuaries[M]. 1st Edition. Amsterdam:Elsevier, 2005.

Savenije H H G. Salinity and tides in alluvial estuaries[M]. 2nd Edition. Amsterdam:Elsevier, 2012.

Umlauf L, Burchard H. A generic length-scale equation for geophysical turbulence models[J]. Journal of Marine Research, 2003, 61(2):235-265.

Pawlowicz R, Beardsley B, Lentz S. Classical tidal harmonic analysis including error estimates in MATLAB using T_TIDE[J]. Computers & Geosciences, 2002, 28(8):929-937.

Godin G. The propagation of tides up rivers with special considerations on the upper Saint Lawrence river[J]. Estuarine, Coastal and Shelf Science, 1999, 48(3):307-324.

Hansen D V, Rattray M. Gravitational circulation in straits and estuaries[J]. Journal of Marine Research, 1965, 23:104-122.

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