Plant community stability is associated with a decoupling of prokaryote and fungal soil networks

Abstract

Soil microbial networks play a crucial role in plant community stability. However, we lack knowledge on the network topologies associated with stability and the pathways that shape these networks. In a 13-year mesocosm experiment, we determined how natural grassland soil and soil abandoned from agricultural practices 60 years before the start of the experiment associated with soil microbial networks. Abandoned arable soil promoted destabilising properties and was associated with soil microbial networks coupled in prokaryote and fungal responses. This coupling was linked with strong associations between prokaryotes, fungi and the plant community with soil chemical composition. Conversely, in stable natural grassland communities, soil prokaryote and fungal responses were decoupled. This decoupling was associated with a large variety of past plant community pathways affecting in particular fungal networks. We conclude that plant community stability is associated with a decoupling of prokaryote and fungal soil networks in which interactions with the plant community play a critical role.