Aridity drives global convergence of desert microbiomes and biogeochemical activities

作者：Pok Man Leung, Sean K. Bay, Wei Wen Wong, Thanavit Jirapanjawat, Stephen D. Archer, Julian E. Beaman, Ameur Cherif, Steven L. Chown, Don A. Cowan, Cecilia Demergasso, Asunción de los Rı́os, Jocelyne DiRuggiero, Bo Elberling, Beat Frey, Osnat Gillor, David W. Graham, Puja Gupta, Ian D. Hogg, Heli Juottonen, Minna‐Maarit Kytöviita, Thulani P. Makhalanyane, Laura Meredith, Thanh Nguyen-Dinh, Anders Priemé, Jean‐Baptiste Ramond, Steven D. Siciliano, Geok Yuan Annie Tan, Kimberley Warren‐Rhodes, Nimrod Wieler, Perran L. M. Cook, Manuel Delgado-Baquerizo, Chris Greening · 发表于：bioRxiv (Cold Spring Harbor Laboratory) · 年份：2025 · DOI：10.1101/2025.11.29.691269 · 被引用次数：3 · 研究领域：Polar Research and Ecology、Biocrusts and Microbial Ecology、Origins and Evolution of Life

Deserts cover a third of the world's surface, supporting unique biomes and ecosystem services. Yet, we lack a comprehensive assessment of what defines and drives the microbial communities that dominate life in these regions. Here, we conducted a standardized field survey in contrasting cold, hot, and polar deserts across the seven continents, and observed geographically distant deserts share similar structure, function, and activities. Desert communities are dominated by genomically streamlined Actinobacteriota and Chloroflexota, and compared with non-desert soils, are significantly enriched with stress tolerance genes, mobile genetic elements, and antiviral strategies, revealing previously unknown ecological and evolutionary dynamics. Metabolically, these communities exhibit reduced capacity for carbohydrate and protein degradation, and instead are enriched for chemosynthetic carbon fixation, continuous energy harvesting using atmospheric trace gases and sunlight, and energy reserve biosynthesis. All sampled soils mediated respiration, trace gas oxidation, and carbon fixation, with detectable activity even in hyper-arid Atacama and Antarctic soils at the margins of life. Driver analyses identified aridity as the primary overriding driver of the microbial communities and biogeochemical activities. Collectively, these findings suggest that aridity selects for metabolically self-sufficient taxa capable of continuously meeting energy and carbon needs independently of vegetation-...