The Impact of Grazing on Plant Community Succession in the Central Pyrenee

The Pyrenees, a region characterized by high biodiversity and complex environmental heterogeneity, has experienced significant changes in traditional grazing practices in recent decades. To investigate the effects of these changes on plant community succession, we selected four landscapes in the Central Pyrenees where grazing management still persists. Within each landscape, we sampled both grazed and ungrazed sites across five successional stages: grassland, erizon-dominated, boxwood-dominated, and pine-dominated communities. Our study aimed to assess the impact of grazing on plant community composition and structure across these successional stages. By comparing grazed and ungrazed sites, we sought to determine how grazing influences the transition between stable states and intermediate stages of succession. Metabarcoding of the 16S rRNA gene was used for the identification of soil prokaryotes, the internal transcribed spacer (ITS) region was used for the identification of soil fungi; and the 18S rRNA gene was used to specifically identify arbuscular mycorrhizal (AM) fungi.