Microorganisms are the unseen pillars of mangrove biodiversity and ecosystem services

Mangrove ecosystems are widely acknowledged in international policy and scientific literature for their crucial ecosystem services, including carbon sequestration, greenhouse gas regulation, food provisioning, and cultural value. Effective mangrove conservation and restoration should account for the biodiversity that underpins ecosystem functioning and services. However, one fundamental layer of this biodiversity remains underrepresented in restoration assessments and monitoring: the microbial world. Microorganisms represent the most abundant and taxonomically diverse components of mangrove sediments and rhizospheres, serving as key mediators of biogeochemical processes and, under certain conditions (e.g., pathogen outbreaks), as potential disruptors of ecosystem services. We propose a roadmap that includes: (i) establishing baseline reference datasets across biogeographic regions, vegetation zones, and tidal elevations to enable distinction between natural variability and anthropogenic degradation, (ii) shifting research focus from descriptive diversity surveys toward establishing causal mechanisms and developing standardized microbial functional indicators that can be scaled from plot-level measurements to landscape-level ecosystem service outcomes, and (iii) integrating microbial monitoring into national and international policy frameworks, supported by capacity-building initiatives, sustained funding mechanisms, and biosecurity protocols for any microbiome-based interventions.