Articles | Volume 23, issue 20
https://doi.org/10.5194/bg-23-7493-2026
© 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-23-7493-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
BG Letters
| Highlight paper
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26 Oct 2026
BG Letters | Highlight paper |
| 26 Oct 2026
| 26 Oct 2026
Warming vs. browning: a dual mechanism behind net ecosystem production of shallow brown aquatic systems
Aleksey Paltsev
CORRESPONDING AUTHOR
Department of Ecology, Environment and Geoscience (EMG), Umeå University, Umeå, Sweden
Department of Ecology, Environment and Geoscience (EMG), Umeå University, Umeå, Sweden
Department of Biosciences, Centre for Biogeochemistry in the Anthropocene (CBA), University of Oslo, Oslo, Norway
Department of Ecoscience (ECOS), Aarhus University, Aarhus, Denmark
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Editorial statement
The study shows that warming and browning both promote heterotrophy in shallow boreal lakes, but through distinct pathways: browning enhances bacterial production and alters stoichiometry of major nutrients (C, N, P), while warming suppresses primary production. The authors consider not only changes in nutrient stoichiometry, but also their potential consequences for ecosystem productivity due to environmental changes. This research topic is timely and likely becomes increasingly important in the future due to climate change.
The study shows that warming and browning both promote heterotrophy in shallow boreal lakes, but...
Short summary
Warming and browning (increasing organic carbon) in aquatic systems both promote heterotrophy via distinct mechanisms: browning alone enhances bacterial production and alters stoichiometry, which suppresses primary production. Browning and warming combined shift aquatic ecosystems toward net heterotrophy. This mesocosm study provides mechanistic insight into interacting drivers of global change, with broad relevance for northern freshwaters undergoing increasing browning and warming.
Warming and browning (increasing organic carbon) in aquatic systems both promote heterotrophy...
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