The ecology and function of soil mosses and their associated microbiome under global change

Mosses represent one of the most ubiquitous groups of non-vascular plants on Earth, occurring across diverse climates and habitats.Emblematic mosses, such as Sphagnum, have key physiological adaptations, including high cation-exchange capacity and the production of recalcitrant phenolic compounds that can facilitate long-term C preservation and peat accumulation.They also provide habitat for highly functional microbiomes, which are key in regulating major nutrient cycles, e.g., via biological nitrogen fixation (BNF) or helping in C sequestration.Unfortunately, climate change is impacting the moss-associated microbiome, leading to critical implications for moss microbiome-mediated biogeochemical cycles.This review seeks to summarize the current state of knowledge about the ecology and function of the microbiome of mosses and their vulnerability to climate change. Impact StatementMosses are ecologically significant non-vascular plants that contribute to multiple ecosystems functioning across diverse terrestrial habitats.Their associated microbiomes also facilitate these processes by taking an active part in various functions linked with nutrient cycles (e.g., BNF).However, climate change may alter these moss-microbe interactions, with potential consequences for microbiome-mediated biogeochemical processes.This manuscript provides a comprehensive overview of moss ecology and associated microbiomes, highlighting their role in regulating soil nutrient cycles in regions where vascular plant abundance is scarce.In this review, we discuss the fundamental ecological and biogeochemical functions of mossassociated microbiomes and evaluate the vulnerability of these vital microbial associations to ongoing climate change.