Plant and soil microbiome following glacier retreat

Glaciers are retreating at an accelerating rate due to global climate warming, profoundly reshaping alpine landscapes. As ice recedes, newly exposed forelands become natural laboratories to study primary succession and ecosystem development. These environments offer unique opportunities to understand how biodiversity colonizes and functions in response to rapid environmental change. In particular, glacier retreat has far-reaching consequences for microbial and plant communities and, consequently, for ecosystem processes such as nutrient cycling and soil formation.In this project, we investigated how glacier retreat influences fungal and bacterial communities and their interactions with plants along a chronosequence spanning approximately 160 years of deglaciation. We sampled bulk soil, rhizosphere soil, and root endosphere from multiple plant species across four stages of deglaciation. Unlike many studies that focus on single plant species, we adopted a community-level approach, encompassing a broad diversity of co-occurring alpine plants to better capture the complexity of plant-microbe associations in these dynamic systems.Our study aimed to (1) characterize the composition and diversity of bacterial and fungal communities across different plant microhabitats (soil, rhizosphere, roots), (2) assess how these communities change along the temporal and spatial gradient of glacier retreat, and (3) reconstruct plant-bacteria and plant-fungi interaction networks to identify key drivers of microbial community assembly and ecosystem functioning. We examined both alpha-diversity (within-sample diversity) and beta-diversity (between-sample variation), as well as the distribution of functional groups associated with different stages of succession. We analyzed a total of 234 microbial communities using high-throughput sequencing approaches, enabling detailed insights into how microbial diversity and function evolve over time and space.Although soil microorganisms play a foundational role in ecological processes and ecosystem functions, they are often overlooked in conservation measures. It is therefore important to understand their fate in fast-changing environments, especially before the extinction of glaciers leads to their disappearance from Earth. Our study contributes to filling this knowledge gap by providing an integrative view of plant-microbe interactions along a glacier foreland. The results underscore the need to consider microbial communities in ecological models and conservation frameworks addressing the impacts of climate change on alpine ecosystems.