热带海洋学报

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南海北部水团及中尺度现象对营养盐时空分布的影响

张金尚1,2,3, 邹定辉1, 马玉2,3,*, 李锐祥2,3, 刘愉强2,3, 孟强2,3, 刘同木2,3, 史华明2,3   

  1. 1.华南理工大学环境与能源学院, 广东 广州 510006;

    2.国家海洋局南海调查技术中心, 广东 广州 510300;

    3.自然资源部海洋环境探测技术与应用重点实验室, 广东 广州 510300;

  • 收稿日期:2022-03-03 修回日期:2022-05-04 出版日期:2022-05-05 发布日期:2022-05-05
  • 通讯作者: 马玉
  • 基金资助:
     广东省海洋经济发展(海洋六大产业)专项资金项目(粤自然资合[2021]038号、粤自然资合[2020]025号); 南方海洋科学与工程广东省实验室(珠海)项目(SML2021SP203); 广东省重点领域研发计划项目(2020B1111020003)

Spatiotemporal distribution and influencing factors of nutrients in the northern South China Sea

ZHANG Jinshang1,2,3, ZOU Dinghui1, MA Yu2,3,*, LI Ruixiang2,3, LIU Yuqiang2,3, MENG Qiang2,3, LIU Tongmu2,3, SHI Huaming2,3   

  1. 1.School of Environment and Energy, South China University of Technology, Guangzhou 510006, China;

    2.South China Sea Marine Survey and Technology Center, State Oceanic Administration, Guangzhou 510300, China;

    3.Key Laboratory of Marine Environmental Survey Technology and Application, Ministry of Natural Resources, Guangzhou 510300, China

  • Received:2022-03-03 Revised:2022-05-04 Online:2022-05-05 Published:2022-05-05
  • Contact: Yu MA
  • Supported by:
     Project Supported by Special Fund for Marine Economic Development (Six Major Marine Industries) of Guangdong Province (GDNRC[2021]038, GDNRC[2020]025); Project Supported by Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) (SML2021SP203); Key-Area Research and Development Project of Guangdong Province (2020B1111020003)

摘要: 2019年在南海北部开展了四个季节的现场调查, 获取了调查海域海水温度、盐度和营养盐等环境要素实测数据。珠江口西侧近岸海域营养盐表现出明显的季节性和区域特征, 除秋季为潜在的氮限制外, 冬、春、夏季均表现为磷限制, 且春季最为显著, 主要受冲淡水输入和陆架水入侵影响。受西南季风强弱和调查海域海底地形差异的影响, 春、夏季珠江口外跨陆架断面(A断面)上升流强度大于海南岛以东跨陆架断面(B断面), 且夏季营养盐等值线的爬升高度和范围大于春季。黑潮水入侵稀释了陆架坡折处以外海域的营养盐含量, 冬季75—150m水体的营养盐含量相比夏季降低了25%以上;El Ni?o期间黑潮水入侵增强, 春、秋季A断面的东沙群岛附近海域75m-150m水体营养盐含量比相邻站位均低20%以上。春季冷涡中心无机氮(dissolved inorganic nitrogen, DIN)、磷酸盐(PO43--P)和硅酸盐(SiO32--Si)相较于边缘区域分别升高了6.42μmol·L-1、0.71μmol·L-1和10.03μmol·L-1, 夏季上升流和中尺度涡共同作用造成了A断面营养盐的凹型结构。综上所述, 南海北部海域营养盐含量主要受冲淡水、上升流、黑潮入侵、中尺度涡旋等因素独立或耦合作用, 呈现复杂多变的时空分布。

关键词: 南海北部, 水团, 中尺度现象, 营养盐, 时空分布

Abstract: Temperature, salinity and nutrients were obtained from four seasonal in-field cruises during 2019 on the Northern South China Sea(NSCS). Due to the Pearl River plume and shelf seawater intrusion, nutrients distribution in the nearshore waters of the western Peal River Estuary(PRE) showed remarkable seasonal and regional variations, which was phosphorus limitation in three seasons, especially significant in spring, while showed potential nitrogen limitation in autumn. Influenced by the strength of southwest monsoon and seafloor topography variation, upwelling intensity of the cross-shelf section outside of the PRE (Section A) was greater than that of the cross-shelf section east of Hainan Island(section B) in spring and summer, and climbing height and range of the nutrient contours were greater in summer than that in spring. Nutrients was diluted by the intrusion of Kuroshio water on the slope area of NSCS, the nutrient concentration between 75 to 150 m in winter decreased more than 25% compared with that in summer, while the nutrient concentration near the Dongsha Island of the section A was less than the adjacent stations by above 20% in spring and autumn, since the reduced Kuroshio water intrusion during El Ni?o. The nutrients in the centre of the cold eddy increased 6.42μmol·L-1 DIN, 0.71μmol·L-1 PO43--P and 10.03μmol·L-1 SiO32--Si respectively compared with the adjacent stations outside of the eddy. The concave structure of nutrient distribution in section A was resulted from the co-effects of upwelling and mesoscale eddy in summer. It is summarized that the spatiotemporal variations of nutrient distribution in the NSCS were complicated, mainly effected by the independent or coupled factors including Pearl River plume, coastal upwelling, Kuroshio intrusion and mesoscale eddies.

Key words: Northern South China Sea, water mass, mesoscale phenomenon, nutrients, spatiotemporal distributions