Articles | Volume 19, issue 7
https://doi.org/10.5194/bg-19-2007-2022
© Author(s) 2022. 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-19-2007-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
11 Apr 2022
Research article |
| 11 Apr 2022
| 11 Apr 2022
Suspended particulate matter drives the spatial segregation of nitrogen turnover along the hyper-turbid Ems estuary
Institute of Geology, Center for Earth System Research and
Sustainability (CEN), University Hamburg, Hamburg, 20146, Germany
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht,
21502, Germany
Tina Sanders
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht,
21502, Germany
Justus E. E. van Beusekom
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht,
21502, Germany
Institute of Oceanography, University Hamburg, Hamburg, 20146, Germany
Yoana G. Voynova
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht,
21502, Germany
Andreas Schöl
Department of Microbial Ecology, Federal Institute of
Hydrology, Koblenz, 56068, Germany
Kirstin Dähnke
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht,
21502, Germany
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In this study, using extensive field observations and a numerical model, we analyzed the physical and biogeochemical structure of a coastal system following an extreme flood event. Our results suggest that a number of anomalous observations were driven by a co-occurrence of peculiar meteorological conditions and increased riverine discharges. Our results call for attention to the combined effects of hydrological and meteorological extremes that are anticipated to increase in frequency.
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Short summary
Estuaries can significantly alter nutrient loads before reaching coastal waters. Our study of the heavily managed Ems estuary (Northern Germany) reveals three zones of nitrogen turnover along the estuary with water-column denitrification in the most upstream hyper-turbid part, nitrate production in the middle reaches and mixing/nitrate uptake in the North Sea. Suspended particulate matter was the overarching control on nitrogen cycling in the hyper-turbid estuary.
Estuaries can significantly alter nutrient loads before reaching coastal waters. Our study of...
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