Biocrust environmental data across Chinese deserts

One of the key goals of ecology is to understand how communities are
assembled. The species co-existence theory suggests that community
β-diversity is influenced by species pool and community assembly
processes, such as environmental filtering, dispersal events, ecological
drift, and biotic interactions. However, it remains unclear whether there
are similar β-diversity patterns among different soil microbial groups and
whether all these mechanisms play significant roles in mediating
β-diversity patterns. By conducting a broad survey across Chinese deserts,
we aimed to address these questions by investing biological soil crusts
(biocrusts). Through amplicon-sequencing, we acquired β-diversity data for
multiple microbial groups, that is, soil total bacteria, diazotrophs,
phoD-harbouring taxa, and fungi. Our results have shown varying distance
decay rates of β-diversity across microbial groups, with soil total
bacteria showing a weaker distance-decay relationship than other groups.
The impact of the species pool on community β-diversity varied across
microbial groups, with soil total bacteria and diazotrophs being
significantly influenced. While the contributions of specific assembly
processes to community β-diversity patterns varied among different
microbial groups, significant effects of local community assembly
processes on β-diversity patterns were consistently observed across all
groups. Homogenous selection and dispersal limitation emerged as crucial
processes for all groups. Precipitation and soil C:P were the key factors
mediating β-diversity for all groups. This study has substantially
advanced our understanding of how the communities of multiple microbial
groups are structured in desert biocrust systems.