Abstract
Fog formation over tropical forests remains poorly characterized, despite its potential role in bioaerosol dispersion and ecosystem processes. Here, we analyzed fog samples collected at the Amazon Tall Tower Observatory using flow cytometry and culture-based techniques to characterize viable microbial communities. Microbial cell concentrations varied over an order of magnitude across 13 fog events, reaching up to 8 × 104 cells per ml of fog water. Flow cytometry consistently detected metabolically active cells, while culturing and mass spectrometry-based identification yielded eight viable bacterial species and seven fungal taxa. The bacteria Serratia marcescens, Ralstonia pickettii and Sphingomonas paucimobilis exhibited seasonal variations in prevalence. The fungal species identified were primarily mesophilic saprophytes and endophytes, commonly associated with soil and plant surfaces. Our findings indicate that fog harbors viable microbes, including Serratia marcescens and Ralstonia pickettii, which may imply a relevance of fog for microbial dispersal, colonization and nutrient cycling in the Amazon rainforest.
Data availability
The datasets generated during and/or analyzed during the current study are available in the Zenodo repository at https://doi.org/10.5281/zenodo.18255540. The SMPS data used in this analysis were obtained from the associated publication and are available at https://doi.org/10.1038/s41561-024-01585-0. All other data supporting the findings of this study are available within the article and its Supplementary Information files, including Source Data.
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Acknowledgements
The authors gratefully acknowledge the essential financial support that made this research possible. We thank ATTO and FINEP (Financing Agency for Studies and Projects) for funding Project 01.22.0258.01, which provided the necessary infrastructure and resources for the development of this work. We also express our gratitude to the National Council for Scientific and Technological Development (CNPq) for supporting the National Institute of Science and Technology (INCT) through grant 408944/2024-2. Special thanks are extended to Bruna Sebben for the master’s scholarship awarded by CAPES (Coordination for the Improvement of Higher Education Personnel), and to Emerson Hara for the postdoctoral fellowship funded by CNPq. These scholarships enabled full dedication to the research activities presented in this study. This research used resources at the Environmental Molecular Sciences Laboratory (EMSL), a DOE Office of Science User Facility. EMSL is sponsored by the Biological and Environmental Research program and operated under Contract No. DE-AC05-76RL01830. Without the generous support of these institutions and agencies and the commitment of the scholarship recipients, this work would not have been feasible.
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R.H.M.G. led the project conceptualization, supervised the study, contributed to formal analysis, investigation, data curation, visualization, writing—original draft, writing—review & editing, and funding acquisition. M.O.A. contributed to project conceptualization, investigation, data curation, writing—original draft, review & editing, and funding acquisition. U.P. contributed to conceptualization, formal analysis, writing—original draft, review & editing, and funding acquisition. S.T.M. contributed to conceptualization, formal analysis, writing—original draft, review & editing, and funding acquisition. C.P. contributed to conceptualization, formal analysis, resources, writing—original draft, review & editing, and funding acquisition. B.W. contributed to conceptualization, software development, resources, writing—original draft, review & editing, and funding acquisition. S.P.-V. contributed to formal analysis, data curation, writing—original draft, and review & editing. E.L.Y.H. contributed to methodology, validation, formal analysis, investigation, writing—original draft, and visualization. B.G.S. contributed to methodology, software, validation, formal analysis, investigation, data curation, writing—original draft, review & editing, and visualization. P.E.T. contributed to conceptualization, formal analysis, investigation, writing—original draft, and review & editing. D.M.C.eS. contributed to validation, formal analysis, investigation, resources, data curation, and writing—original draft. S.B. contributed to validation, software, formal analysis, investigation, resources, data curation, writing—original draft, review & editing, and visualization. V.B.D.F. contributed to validation, formal analysis, investigation, resources, and data curation. G.V. contributed to validation, formal analysis, investigation, resources, data curation, writing—original draft, and review & editing. L.F.H. contributed to methodology, formal analysis, data curation, writing—original draft, and review & editing. R.R.F. contributed to software, investigation, resources, and data curation. C.Q.D.-J. contributed to software, formal analysis, investigation, resources, data curation, writing—original draft, and review & editing. M.C.M. contributed to methodology, validation, formal analysis, and visualization. F.L.T.G. & R.F.C.M. contributed to formal analysis, resources, writing—original draft, and review & editing. R.I.A. contributed to software, formal analysis, writing—original draft, and review & editing. N.N.L. contributed to validation, formal analysis, investigation, resources, and data curation. G.V. contributed to validation, formal analysis, investigation, and data curation. S.C. contributed to formal analysis, resources, writing—original draft, review & editing, and funding acquisition. C.I.Y. contributed to validation, formal analysis, resources, data curation, writing—original draft, and review & editing. R.D.P. contributed to validation, formal analysis, investigation, resources, data curation, and writing—original draft. R.A.F.S. contributed to formal analysis, investigation, resources, data curation, writing—original draft, and review & editing. T.P. contributed to validation, formal analysis, investigation, data curation, writing—original draft, and review & editing. P.A. contributed to conceptualization, formal analysis, writing—original draft, and review & editing. L.A.T.M. contributed to software, formal analysis, data curation, writing—original draft, and review & editing. H.E. & I.K. contributed to formal analysis, data curation, writing—original draft, and review & editing. J.C.S.-S. contributed to validation, formal analysis, investigation, data curation, writing—original draft, and visualization. S.S.R. contributed to formal analysis, investigation, resources, data curation, writing—original draft, and visualization. J.W. contributed to validation, formal analysis, investigation, resources, writing—original draft, review & editing, and visualization. L.C.V. contributed to validation, formal analysis, data curation, writing—original draft, and review & editing.
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Godoi, R.H.M., Hara, E.L.Y., Sebben, B.G. et al. Amazonian fog harbors viable microbes. Commun Earth Environ (2026). https://doi.org/10.1038/s43247-026-03233-4
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DOI: https://doi.org/10.1038/s43247-026-03233-4
