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摘要：
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| 选取2016年枯水期实测咸情资料，分析东江下游虎门水道盐水运动规律及输运机制。结果表明：欧拉余流输运、垂向环流输运及潮泵输运决定了虎门水道内盐水的上溯和下落。虎门以上咸淡水充分或部分混合，欧拉余流及潮泵输运是盐分输运的主要动力；半月潮的潮差增强期盐水随潮变化形成陆向的脉冲式上溯，中潮涨憩时咸界最远；半月潮的潮差减弱期盐度趋近于零。虎门以下小潮阶段咸淡水分层特征显著，垂向环流输运较强，在密度梯度力作用下，表底层流速出现反向；潮差增强期，咸淡水掺混逐步加强，表层盐度持续上升，至中潮期达到峰值；潮差减弱期，表底层混合相对均匀，盐度值减小。由于口门上下游盐分输运方向相反，盐分主要在口门以下积累；口门以上水域的盐度最大值主要由潮差增强期的平流输运决定。因此，可从减弱涨潮动力及降低下游盐度两个方面着手，抑制虎门水道及上游东江三角洲的咸潮上溯。 |
| In recent years, saltwater intrusion in the Dongjiang River Delta has intensified significantly, threatening water supply security in Guangzhou, Dongguan, and other regions. It is thus imperative to conduct indepth research on the saltwater movement mechanisms from the Dongjiang Delta to the Humen Channel estuary and guide salt suppression practices. This paper analyzes the patterns and transport mechanisms of saltwater movement of the Humen Channel downstream Dongjiang River Delta during the dry season of 2016 using field salinity data. The results show that the upstream intrusion and downstream retreat of saltwater in the Humen Channel are governed by three transport mechanisms: Eulerian residual flow transport, vertical circulation transport, and tidal pumping transport. Upstream of Humen: Saltwater and freshwater are fully or partially mixed. Eulerian residual flow and tidal pumping serve as the primary drivers of salt transport. During the transition to spring tide, saltwater exhibits pulsed, landward intrusion synchronized with tidal cycles, with the saltwater front reaching its maximum upstream extent at flood slack at medium tide. During the transition to neap tide salinity approaches zero. Downstream of Humen: Significant stratification between saltwater and freshwater occurs during the neap tide. Vertical circulation transport dominates, driven by density gradients, resulting in opposing flow directions in the surface and bottom layers. As tidal range increases(transition to spring tide), mixing gradually intensifies, leading to a continuous rise in surface salinity that peaks during the medium tide period. During the transition to neap tide, vertical mixing becomes relatively uniform, and salinity decreases. Due to opposing salt transport directions upstream and downstream of the estuary mouth, salt primarily accumulates downstream of the mouth. The peak salinity levels upstream of the mouth are predominantly determined by advective transport during the spring tidal phase. Therefore, suppressing saltwater intrusion in the Humen Channel and the upstream Dongjiang Delta can be approached from two angles: reducing tidal influx momentum and lowering downstream salinity levels. |
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参考文献：
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[1] 陈文龙,马志鹏,袁菲,等.粤港澳大湾区水安全协同调控理论框架研究[J]. 水资源保护, 2023, 39(1):22-31.CHEN W L, MA Z P, YUAN F, et al. Theoretical framework of water security collaborative regulation and control in GuangdongHong Kong-Macao Greater Bay Area[J]. Water Resources Protection, 2023, 39(1):22-31.
[2] 杨芳,陈文龙,卢陈,等.粤港澳大湾区咸潮综合防控体系研究[J]. 水资源保护, 2023, 39(1):32-41.YANG F, CHEN W L, LU C, et al. Research on comprehensive prevention and control system of saltwater intrusion in the Guangdong-Hong Kong-Macao Greater Bay Area[J]. Water Resources Protection, 2023, 39(1):32-41.
[3] 钱燕,卢康明. 2021年珠江流域旱情分析与思考[J]. 中国防汛抗旱, 2022, 32(6):27-30.QIAN Y, LU K M. Brief analysis and thoughts on the drought of the Pearl River basin in 2021[J]. China Flood&Drought Management, 2022, 32(6):27-30.
[4] 陈荣力,刘诚,高时友.磨刀门水道枯季咸潮上溯规律分析[J]. 水动力学研究与进展A辑, 2011, 26(3):312-317.CHEN R L, LIU C, GAO S Y. Analysis of the mechanism on the saltwater intrusion in Modaomen estuary[J]. Chinese Journal of Hydrodynamics, 2011, 26(3):312-317.
[5] GONG W P, MAA J P Y, HONG B, et al. Salt transport during a dry season in the Modaomen Estuary, Pearl River Delta, China[J]. Ocean&Coastal Management, 2014, 100:139-150.
[6] 高时友,陈子燊.珠江口磨刀门水道枯季咸潮上溯与盐度输运机理分析[J]. 海洋通报, 2016, 35(6):625-631.GAO S Y, CHEN Z S. Analysis on salinity transport mechanism for the Modaomen waterway of Pearl River in the dry season[J]. Marine Science Bulletin, 2016, 35(6):625-631.
[7] LIU C J, YU M H, JIA L W, et al. Impacts of physical alterations on salt transport during the dry season in the Modaomen Estuary,Pearl River Delta, China[J]. Estuarine, Coastal and Shelf Science,2019, 227:106345.
[8] GONG W P, LIN Z Y, ZHANG H, et al. The response of salt intrusion to changes in river discharge, tidal range, and winds,based on wavelet analysis in the Modaomen estuary, China[J]. Ocean&Coastal Management, 2022, 219:106060.
[9] 胥加仕. 2021年珠江流域抗旱保供水工作实践与启示[J]. 中国水利, 2022(1):8-11.XU J S. Practice and enlightenment of drought resistance and water supply assurance in the Pearl River Basin in 2021[J]. China Water Resources, 2022(1):8-11.
[10] 刘祖发,关帅,张淦濠,等.基于FVCOM的虎门水道盐水入侵三维数值模拟[J]. 热带海洋学报, 2016, 35(2):10-18.LIU Z F, GUAN S, ZHANG J H, et al. Three-dimensional numerical simulation of saltwater intrusion into the Humen estuary based on FVCOM[J]. Journal of Tropical Oceanography,2016, 35(2):10-18.
[11] 林中源,唐琦,王凤恩,等.特枯水年珠江流域东江三角洲压咸调度预演与策略[J]. 人民珠江, 2024, 45(7):58-66.LIN Z Y, TANG Q, WANG F E, et al. Simulation and strategy for salinity control scheduling in Dongjiang Delta of Pearl River basin in severe drought year[J]. Pearl River, 2024, 45(7):58-66.
[12] 杨芳,邹华志,卢陈,等.东江三角洲咸潮加剧原因和对策探讨[J]. 中国水利, 2022(4):28-30.YANG F, ZOU H Z, LU C, et al. Study on reasons and measures to increasing seawater intrusion in Dongjiang Delta[J]. China Water Resources, 2022(4):28-30.
[13] 杨芳,林中源,邹华志,等.极端干旱条件下珠江口东江三角洲咸潮上溯响应规律研究[J]. 海洋通报, 2023, 42(5):496-507.YANG F, LIN Z Y, ZOU H Z, et al. Study on the response law of saltwater intrusion in the Dongjiang Delta of the Pearl River Estuary under extreme drought conditions[J]. Marine Science Bulletin, 2023, 42(5):496-507.
[14] 陈晖,黄广灵,谭超,等.东江咸潮上溯特征及盐度输运机理浅析[J]. 水资源保护, 2023, 39(6):195-203.CHEN H, HUANG G L, TAN C, et al. Analysis of saltwater intrusion characteristics and salinity transport mechanism in the Dongjiang River[J]. Water Resources Protection, 2023, 39(6):195-203.
[15] 应秩甫,陈世光.珠江口伶仃洋咸淡水混合特征[J]. 海洋学报,1983, 5(1):1-10.YING Z P, CHEN S G. Characteristics of saltwater-freshwater mixing in the Lingdingyang Estuary of the Pearl River[J]. Acta Oceanologica Sinica, 1983, 5(1):1-10. |
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