极地研究

极地研究 ›› 2025, Vol. 37 ›› Issue (4): 658-667.DOI: 10.13679/j.jdyj.20240023

所属学科：极地海洋化学

• 研究论文 • 上一篇    下一篇

硝酸盐及其氮、氧同位素指示白令海沉积物中的硝酸盐转化过程

陈佳钦1, 陈玲1, 庄燕培2, 任健1, 季仲强1, 白有成1, 杨志1, 李杨杰1, 陈建芳1,3,4, 金海燕1,3,5,6   

  1. 1自然资源部第二海洋研究所, 海洋生态系统动力学重点实验室, 浙江 杭州 310012;
    2 集美大学极地与海洋研究院, 福建 厦门 361021;
    3上海交通大学海洋学院, 上海 200240;
    4卫星海洋环境监测预警全国重点实验室, 浙江 杭州 310012;
    5南方海洋科学与工程广东省实验室(珠海), 广东 珠海 5190823;
    6东海实验室, 浙江 舟山 316000
  • 收稿日期:2024-03-06 修回日期:2024-05-09 出版日期:2025-12-30 发布日期:2026-01-12
  • 通讯作者: 金海燕
  • 基金资助:
    国家重点研发计划和国家自然科学基金资助

Concentrations of nitrate and its dual isotopes in Bering Sea sediments reveal nitrate transformation processes

CHEN Jiaqin1, CHEN Ling1, ZHUANG Yanpei 2, REN Jian1, JI Zhongqiang1, BAI Youcheng1, YANG Zhi1, LI Yangjie1, CHEN Jianfang1,3,4, JIN Haiyan1,3,5,6   

  1. 1 Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China;
    2 Polar and Marine Research Institute, Jimei University, Xiamen 361021, China;
    3 School of Oceanography, Shanghai Jiaotong University, Shanghai 200240, China;
    4 State Key Laboratory of Satellite Ocean Environment Dynamics, Hangzhou 310012, China;
    5 Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai 5190823, China;
    6 Donghai Laboratory, Zhoushan 316000, China
  • Received:2024-03-06 Revised:2024-05-09 Online:2025-12-30 Published:2026-01-12

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摘要： 海洋沉积物中同时发生着硝化作用、反硝化作用等氮转化过程, 影响着海洋硝酸盐(NO3–)循环。研究白令海沉积物中同时发生的硝化和反硝化作用等氮转化过程, 对于了解极地和亚极地海域的氮循环具有重要意义。本文选取中国第5次和第7次北极科学考察过程中采集的白令海盆(BL-10)和白令海陆架(B12)两个多管沉积物柱状样中的沉积物间隙水, 分析其NO3–浓度及其稳定氮、氧同位素(d15N-NO3–, d18O-NO3–)值, 以探究NO3–及其氮、氧同位素指示白令海沉积物NO3–的转化过程。研究结果表明: (1)BL-10沉积物间隙水中的NO3–浓度范围为0.61~22.52 μmol·L–1, d15N-NO3–范围为3.6‰~17.8‰, d18O-NO3–范围为10.5‰~20.9‰, 沉积物间隙水中发生了硝化-反硝化耦合作用; (2)B12沉积物间隙水中的NO3–浓度范围为0.20~1.61 μmol·L–1, 远低于底层水中的NO3–浓度(18.60 μmol·L–1), 其中0~2 cm的d15N-NO3–范围为10.3‰~16.4‰, d18O-NO3–范围为13.2‰~19.7‰, 其表层沉积物间隙水中发生了剧烈的反硝化作用; (3)在白令海, 受水深、初级生产力和沉积物有机碳含量的共同作用, 陆架区域的反硝化作用比海盆区更加剧烈。

关键词: 硝酸盐, 氮氧同位素, 沉积物间隙水, 转化过程, 白令海

Abstract:

Simultaneous nitrification and denitrification processes happened in marine sediments affect the nitrate (NO3–) cycling in the Ocean. Studies of nitrogen (N) transformation processes occurring in Bering Sea sediments are crucial for improving our understanding of the N cycling in polar and subpolar marine regions. In this study, we conducted preliminary analyses of nitrate and its stable nitrogen and oxygen isotopes (d15N-NO3–, d18O-NO3–) in the sediment pore water in Bering Sea sediments. Samples were extracted from sediment cores collected during the 5th Chinese Arctic Research Expedition from the Bering Sea Basin (BL-10) and the 7th Chinese Arctic Research Expedition from the Bering Sea shelf (B12). The results show that: (1) at BL-10 station, nitrate concentration in pore water was 0.61~22.52 μmol·L–1, d15N-NO3– was 3.6‰~17.8‰, and d18O-NO3– was 10.5‰~20.9‰, suggesting coupling between nitrification-denitrification process. (2) At B12 station, the nitrate concentration in sediment pore water was 0.20~1.61 μmol·L–1, in 0~2 cm d15N-NO3– was 10.3‰~16.4‰, d18O-NO3– was 13.2‰~19.7‰, which was significantly lower than that in bottom sea (18.60 μmol·L–1). This indicates intense denitrification in the surface sediment pore water. (3) Denitrification appears to be more intense in shelf than in basin sediments because of the combined influence of water depth, primary productivity, and sediment organic carbon content.


Key words: nitrate, nitrogen and oxygen isotopes, sediment pore water, transformation process, Bering Sea