Bacterial and fungal representation and interactions in a former degraded upland peatland vegetation mosaic undergoing restoration

Peatlands are under threat from land management, anthropogenic pollution and climate change. These factors are implicated in severe degradation of ombrotrophic peatlands in the Southern Pennines of northern England. Significant areas of unconsolidated bare peat are both highly vulnerable to peat erosion and resistant to natural re-vegetation. Restoration efforts during the last 30 years have included liming and fertilisation of bare peat allowing transient growth of introduced lowland grass species for peat stabilisation that facilitates establishment of Calluna vulgaris and other dwarf shrubs. Key restoration goals through revegetation of bare peat are to increase biodiversity and recover hydrological, and retain carbon storage, functions.

Below-ground bacterial and fungal communities were characterised in tandem across this vegetation mosaic using high-throughput sequencing of respective phylogenetic markers (16S and ITS1). Restoration activities were reflected in changes in plant cover and the below-ground microbial community, which based on the situation in other ecosystems, are likely to be of functional importance in relation to restoration goals and future land management planning. Bare peat supported increased ligninolytic Basidiomycota and oligotrophic bacteria. In vegetated zones, root-associated Archaeorhizomyces and -symbiotic ericoid- and ectomycorrhizal fungal taxa were highly represented although arbuscular mycorrhizal taxa were rare. Candidate indicator microbes of relevance to monitoring and restoration of peatlands were identified. Bacterial and fungal co-occurrence was examined through cross-kingdom network analyses, revealing putative functional groups linked to vegetation and edaphic status of relevance to maintenance and restoration of peatland function.

Funded by Manchester Metropolitan University and Moors for the Future Partnership. See also New Phytologist Symposium 33 conference poster.