Data for: Cessation of grazing causes biodiversity loss and homogenization of soil food webs

There is widespread concern that cessation of grazing in historically
grazed ecosystems is causing biotic homogenization and biodiversity loss.
We used 12 montane grassland sites along an 800-km north-south gradient
across the United Kingdom, to test whether cessation of grazing
affects local ɑ- and β-diversity of belowground food
webs. We show cessation of grazing leads to strongly decreased
ɑ-diversity of most groups of soil microbes and fauna, particularly of
relatively rare taxa. In contrast, the β-diversity varied between groups
of soil organisms. While most soil microbial communities exhibited
increased homogenization after cessation of grazing, we observed decreased
homogenization for soil fauna after cessation of grazing. Overall, our
results indicate that exclusion of domesticated herbivores from
historically grazed montane grasslands has far-ranging negative
consequences for diversity of belowground food webs. This underscores the
importance of grazers for maintaining the diversity of belowground
communities, which play a central role in ecosystem functioning.