Nitrogen fixation under the interaction of Kuroshio and upwelling in the northeastern South China Sea

文献类型： 外文期刊

第一作者： Liu, Jiaxing

作者： Liu, Jiaxing;Ding, Xiang;Zhou, Linbin;Ke, Zhixin;Tan, Yehui;Tan, Yehui;Zhang, Huangchen;Li, Jiajun

作者机构：

关键词： Trichodesmium; Unicellular nitrogen -fixing cyanobacteria; Dissolved organic phosphorus; Coastal upwelling; Kuroshio current

期刊名称：DEEP-SEA RESEARCH PART I-OCEANOGRAPHIC RESEARCH PAPERS （ 影响因子：2.4； 五年影响因子：3.1 ）

ISSN： 0967-0637

年卷期： 2023 年 200 卷

页码：

收录情况： SCI

摘要： Diazotrophic organisms are vulnerable to physical dynamic processes. However, the interactions and mechanisms of multiple dynamic processes on nitrogen fixation remain unclear. This study aimed to investigate one of these interactions; we conducted field investigations and bioassay experiments in the northeastern South China Sea, which faces the Kuroshio current and coastal upwelling. Using 15N tracer and molecular biology methods, we found that the eastern Guangdong upwelling, having high phosphorus and a lower N:P ratio, had higher nitrogen fixation rates as well as a higher abundance of diazotrophic cyanobacteria Trichodesmium spp. and UCYN-A compared with nonupwelling area. Additionally, a higher abundance of diazotrophic cyanobacteria occurred near the bottom of the euphotic zone along the shelf break that was affected by the Kuroshio current. Field incubation experiments confirmed that phosphorus increased the nitrogen fixation rates and stimulated the growth of cyanobacteria in the area affected by upwelling. Taken together, our results indicated that warmer surface water with a high N:P ratio likely mixed with upwelled phosphorus-rich water containing diazotrophic cyanobacteria, which were transported by the intensified Kuroshio current under the influence of the 2015/16 El Nin similar to o. This mixing then triggered a high abundance of diazotrophic cyanobacteria. These findings provide new insights into how the interaction of multiple dynamic processes can regulate nitrogen fixation.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序