Articles | Volume 23, issue 15
https://doi.org/10.5194/bg-23-5533-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-5533-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Aug 2026
Research article |
| 11 Aug 2026
| 11 Aug 2026
Estuarine mixing drives organic nitrogen transformation and bioavailability dynamics
Chenglong Han
Tianjin Key Laboratory of Environmental Technology for Complex Trans-media Pollution, Tianjin International Joint Research Center for Environmental Biogeochemical Technology, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
Shaojun Qiu
Tianjin Key Laboratory of Environmental Technology for Complex Trans-media Pollution, Tianjin International Joint Research Center for Environmental Biogeochemical Technology, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
Xinyi Li
Tianjin Key Laboratory of Environmental Technology for Complex Trans-media Pollution, Tianjin International Joint Research Center for Environmental Biogeochemical Technology, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
Ying Ke
Tianjin Key Laboratory of Environmental Technology for Complex Trans-media Pollution, Tianjin International Joint Research Center for Environmental Biogeochemical Technology, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
Rolf D. Vogt
Norwegian Institute for Water Research, Oslo 0579, Norway
Xueqiang Lu
CORRESPONDING AUTHOR
Tianjin Key Laboratory of Environmental Technology for Complex Trans-media Pollution, Tianjin International Joint Research Center for Environmental Biogeochemical Technology, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
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Short summary
Estuaries shape how nitrogen from rivers reaches the sea. We mixed river and seawater across a range of salinities and traced organic nitrogen using light signals and isotope patterns. Salt rapidly made much of the land-derived material stick to particles, boosting long-term burial in sediments. Meanwhile, microbes converted part of the remaining dissolved nitrogen into smaller compounds and ammonia that algae can use. These linked processes improve forecasts and management of coastal nitrogen.
Estuaries shape how nitrogen from rivers reaches the sea. We mixed river and seawater across a...
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