Year: 2026
Type: preprint
Abstract: Hydrostatic pressure defines the deep ocean, yet its role in structuring microbial activity across the subseafloor biosphere remains poorly understood. Here, we assessed pressure effects on anabolic activity in sediment communities across margin-proximal, bathyal, abyssal, and hadal settings of the Puerto Rico Trench (493-8,385 m water depth). Community-level responses to pressure reversed with burial, revealing an unrecognized shift toward piezophily in communities down to 20 meters below seafloor (mbsf). Atmospheric pressure yielded higher proportions of active cells in surficial sediments, whereas in situ pressure yielded higher proportions in the subseafloor. Pressure also structured active-community composition; in trench-axis sediments down to 8.35 mbsf, JS1/Atribacterota populations within widespread hadal lineages exhibited a physiological response to in situ pressure, indicative of subseafloor piezophily. These findings suggest that hydrostatic pressure acts as an ecological filter after burial, favoring piezophilic traits that may support microbial persistence in the deep subseafloor biosphere.
Authors: Miguel Desmarais, Corinna Breusing, Anna H. Finch, Chloe M. J. Baumas, William D. Orsi, Alvaro M. Plominsky, Yuki Morono, Laura M. Wehrmann, Dennis Graham, Robert A. Pockalny, Arthur J. Spivack, Irita Aylward, Taylor Walton, Barbara Saucedo, Sofia Rivera Soto, Jelis Sostre-Cortes, Ying Zhang, Evan A. Solomon, David C. Smith, Anne E. Dekas, Jeffrey S. Bowman, Steven D'Hondt, Douglas H. Bartlett
Institutions: Scripps Institution of Oceanography, University of California San Diego, University of Rhode Island, Stanford University, Ludwig-Maximilians-Universität München, Japan Agency for Marine-Earth Science and Technology, Stony Brook University, University of Washington, University of Puerto Rico-Mayaguez
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
SDG: Life below water
Open Access status: green
Funders: National Aeronautics and Space Administration, National Institutes of Health, Japan Agency for Marine-Earth Science and Technology, National Institute of Neurological Disorders and Stroke, School of Medicine, University of California, San Diego, Genome Center, University of California, Davis
OpenAlex ID: W7215098557