Microbial succession and assembly shaped by sulfur, spatial partitioning, and water flow in a volcanic acidic river of northern Patagonia
Year: 2026
Type: article
Abstract: Extreme acidic environments represent natural laboratories for investigating the mechanisms of microbial community assembly, yet the ecological processes structuring these communities remain incompletely understood. Here, we investigate how spatial partitioning, hydrodynamics, and colonization history shape microbial succession in a unique sulfur-rich, acidic river of volcanic origin in northern Patagonia. We combined 16S rRNA gene profiling and shotgun metagenomics with a multi-scale experimental framework encompassing water column fractionation and colonization assays under native and controlled conditions. Microbial diversity was strongly influenced by spatial fractionation, with free-living communities exhibiting higher richness and temporal variability than particle-associated assemblages. Water flow modulated community structure, increasing evenness in free-living fractions under high-flow conditions, but had limited impact on particle-attached communities. Colonization of sulfur-beads followed a structured successional trajectory, with autotrophic sulfur oxidizers dominating early stages and heterotrophs adapted to biofilm lifestyles increasing over time. Ex situ recolonization assays revealed strong priority effects, with initial colonizers determining successional trajectories. Turnover analyses revealed that the balance among stochastic and deterministic assembly processes shifted across communities with pronounced stochasticity in the water column and flow-dependent effects in free-living communities, while biofilm associated communities on sulfur-beads exhibited stronger contribution of deterministic selection. These ecological patterns were mirrored by functional differentiation, with gene enrichment analyses revealing adaptive signatures of substrate attachment and resource acquisition. By integrating fine-scale environmental variation with colonization dynamics, this study reveals how microscale habitat structure and temporal fluxes jointly modulate microbial community assembly rules, offering a nuanced framework to dissect ecological processes in extreme systems.
Source: The ISME Journal
Institutions: San Sebastián University, Metropolitan University of Technology, Universidad Tecnológica Metropolitana, Consejo Nacional de Investigaciones Científicas y Técnicas, Universidad Nacional del Comahue, Natural History Museum, Bangor University, Coventry University, Pontificia Universidad Católica de Chile, Universidad Mayor, Millenium Institute Center for Genome Regulation, University of Concepción, Millennium Institute of Oceanography, Centro Científico Tecnológico - Patagonia Norte
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,153
Awards: G1060648662, G1950977545, PHYSICAL HETEROGENEITY IN BIOMINING BIOFILMS TOWARDS DECIPHERING EXTRACELLULAR POLYMER PRODUCTION AND THE ROLE OF DIFFUSIBLE SIGNAL FACTORS, MOLECULAR DELIVERY PLATFORM BASED ON LIPIDIC NANOPARTICLES FOR ACID MINE DRAINAGE (AMD) MICROBIAL COMMUNITIES ENGINEERING AND CONTROL PROOF OF CONCEPT, METAMOBILOME OF EL TATIO GEOTHERMAL FIELD A MODEL ECOSYSTEM TO STUDY LOCAL MOBILE GENETIC ELEMENT DISPERSAL PREVALENCE AND ROLE IN HOST ADAPTATION AND ECOEVOLUTION., ACIDIC MICROBIOMES AS MODEL SYSTEMS IN ECO-EVOLUTIONARY STUDIES OF COMMUNITY ASSEMBLY PROCESSES, G6131236365, MICROBIAL MICRODIVERSIFICATION AS A STRATEGY FOR FUNCTIONAL EQUILIBRIUM UNDER EXTREME SELECTION, G646719516, SIGNALING IN CHEMOLITOAUTOTROPHIC ACIDOPHILIC BACTERIA A ROLE FOR OUTER MEMBRANE VESICLES IN BIOFILM FORMATION., CENTRO CIENTIFICO TECNOLOGICO DE EXCELENCIA CIENCIA & VIDA (CIENCIA & VIDA)
OpenAlex ID: W7134225181