Articles | Volume 23, issue 11
https://doi.org/10.5194/bg-23-3887-2026
© 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-23-3887-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
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12 Jun 2026
Research article | Highlight paper |
| 12 Jun 2026
| 12 Jun 2026
Denitrification as the dominant process in nitrous oxide production in the water column of two eutrophic reservoirs
Elizabeth Leon-Palmero
CORRESPONDING AUTHOR
Departamento de Ecología and Instituto del Agua, Universidad de Granada, Granada, 18071, Spain
Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
current address: Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
Claudia Frey
Department of Environmental Science, University of Basel, Basel, 4056, Switzerland
Bess B. Ward
Department of Geosciences, Princeton University, Princeton, NJ, 08544, USA
Rafael Morales-Baquero
Departamento de Ecología and Instituto del Agua, Universidad de Granada, Granada, 18071, Spain
Isabel Reche
Departamento de Ecología and Instituto del Agua, Universidad de Granada, Granada, 18071, Spain
Research Unit Modeling Nature (MNat), Universidad de Granada, Granada, 18071, Spain
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Editorial statement
This study highlights reservoirs, which are widespread and expanding human made systems, as significant sources of nitrous oxide, with important implications for climate policy and water management. It provides a major advance by directly quantifying nitrous oxide production pathways in eutrophic reservoirs. Addressing key issues of climate change, water quality, and greenhouse gas emissions, the work is both timely and highly relevant. Conducted in Mediterranean systems, it also offers valuable insights for regional and global understanding of human impacts on biogeochemical cycles.
This study highlights reservoirs, which are widespread and expanding human made systems, as...
Short summary
Reservoirs act as nitrogen sinks and emit nitrous oxide, a potent greenhouse gas and major ozone-depleting substance. We studied two reservoirs and found that nitrification and denitrification produce nitrous oxide in the water column, but denitrification is the main source, fueled by fresh organic matter from phytoplankton. Our results also suggest that nitrous oxide is actively consumed. This study highlights the need to include reservoirs in global nitrous oxide budgets.
Reservoirs act as nitrogen sinks and emit nitrous oxide, a potent greenhouse gas and major...
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