Lowland Tropical Forests Remain a Methane Sink Under Warming and Long-Term Hurricane Disturbance Recovery

Authors

• Gabriele Larocca Conte, Chapman UniversityFollow
• Lucia Zuvela, Macalester College
• Rachel Cruz-Pérez, Pennsylvania State University
• Tatiana Barreto-Vélez, U.S.D.A. Forest Service
• Nibia Becerra-Santillan, Macalester College
• Sophia F. Campbell, George Washington University
• Hieu P. Chu, Macalester College
• Trung Dam, Macalester College
• Iana F. Grullón-Penkova, U.S.D.A. Forest Service
• Miriam Kleit, Macalester College
• Deyaneira A. Ortiz-Iglesias, U.S.D.A. Forest Service
• Laura C. Rubio-Lebrón, U.S.D.A. Forest Service
• Molly A. Cavaleri, Michigan Technological University
• Sasha C. Reed, U.S. Geological Survey
• Debjani Sihi, North Carolina State University
• Tana E. Wood, U.S.D.A. Forest Service
• Christine S. O'Connell, Chapman UniversityFollow

Document Type

Article

Publication Date

5-23-2026

Abstract

Methane (CH₄) is a potent greenhouse gas, and tropical forests account for roughly one–third of global atmospheric CH₄ uptake by soils. Projected warming and more frequent hurricanes in these ecosystems may alter soil CH₄ sink strength, as warmer and wetter soils enhance methanogenesis activity. We measured soil CH₄ and CO₂ efflux during the calendar summer months of 2023 and 2024 alongside continuous records of soil moisture, soil and air temperature, and precipitation in an in–situ warming experiment (TRACE) located in a lowland tropical forest in Puerto Rico, six to seven years after Hurricanes Irma and Maria (2017). The realized warming (∼1.95°C) enhanced soil respiration only in summer 2023 (p < 0.05), but net soil CH₄ uptake was invariant in both campaigns (p > 0.05). Instead, sampling day and between–plot variability explained soil CH₄ dynamics much more than treatment contrasts. Importantly, CH₄ uptake was consistently coupled to CO₂ efflux, suggesting tight linkages between methanotrophic and heterotrophic activities. Between treatments, CH₄ and CO₂ responses to soil temperature variation were less sensitive in warmed plots, which may suggest weak metabolic upregulation under elevated temperatures. Together, these findings indicate that lowland tropical soils remain CH₄ sink even under warming and years after hurricane disturbance, with CH₄ dynamics driven more by spatial and temporal variability than experimental warming. Long–term, high–resolution monitoring integrating soil biogeochemistry and microbial processes will be critical to determine whether the observed net CH₄ uptake signal represents a sustainable or transient response under continued warming and disturbance.

Comments

This article was originally published in Agricultural and Forest Meteorology, volume 386, in 2026. https://doi.org/10.1016/j.agrformet.2026.111225

Recommended Citation

Larocca Conte, G., Zuvela, L., Cruz-Pérez, R., Barreto-Vélez, T., Becerra-Santillan, N., Campbell, S.F., Chu, H.P., Dam, T., Grullón-Penkova, I.F., Kleit, M., Ortiz-Iglesias, D.A., Rubio-Lebrón, L.C., Cavaleri, M.A., Reed, S.C., Sihi, D., Wood, T.E., O’Connell, C.S., 2026. Lowland tropical forests remain a methane sink under warming and long-term hurricane disturbance recovery. Agricultural and Forest Meteorology 386, 111225. https://doi.org/10.1016/j.agrformet.2026.111225

Copyright

The authors

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 License.