Articles | Volume 23, issue 2
https://doi.org/10.5194/bg-23-727-2026
© 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-23-727-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
26 Jan 2026
Research article |
| 26 Jan 2026
| 26 Jan 2026
Variability of greenhouse gas (CH4 and CO2) emissions in a subtropical hydroelectric reservoir: Nam Theun 2 (Lao PDR)
Anh-Thái Hoàng
CORRESPONDING AUTHOR
Université de Toulouse, CNRS, IRD, LAERO, Toulouse, France
Université de Toulouse, CNRS, IRD, GET, Toulouse, France
Frédéric Guérin
Université de Toulouse, CNRS, IRD, GET, Toulouse, France
Chandrashekhar Deshmukh
Asia Pacific Resources International Ltd., Kabupaten Pelalawan, Indonesia
Axay Vongkhamsao
Nam Theun 2 Power Company Limited (NTPC), Environment & Social Division, Water Quality and Biodiversity Dept., Gnommalath Office, P.O. Box 5862, Vientiane, Lao PDR
Saysoulinthone Sopraseuth
Nam Theun 2 Power Company Limited (NTPC), Environment & Social Division, Water Quality and Biodiversity Dept., Gnommalath Office, P.O. Box 5862, Vientiane, Lao PDR
Vincent Chanudet
Electricité de France, Hydro Engineering Centre, Sustainable Development Dpt., Savoie Technolac, 73290 La Motte Servolex, France
Stéphane Descloux
Electricité de France, Hydro Engineering Centre, Sustainable Development Dpt., Savoie Technolac, 73290 La Motte Servolex, France
Nurholis Nurholis
Asia Pacific Resources International Ltd., Kabupaten Pelalawan, Indonesia
Ari Putra Susanto
Asia Pacific Resources International Ltd., Kabupaten Pelalawan, Indonesia
Toan Vu Duc
Research of Organic Matter Group (ROOM), Environmental and Life Science Research Laboratory, Thuy Loi University, Hanoi, Vietnam
Dominique Serça
Université de Toulouse, CNRS, IRD, LAERO, Toulouse, France
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Short summary
We studied greenhouse gas emissions from a large reservoir in Laos over 14 years to understand carbon cycling and changes over time. Methane release through bubbling remained high, while other pathways, like diffusion and degassing, declined. These findings show how emissions evolve as reservoirs age and highlight the value of long-term studies for understanding the climate impact of hydropower.
We studied greenhouse gas emissions from a large reservoir in Laos over 14 years to understand...
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