Data from: Spatial patterning of soil microbial communities created by fungus-farming termites

Spatially overdispersed mounds of fungus-farming termites
(Macrotermitinae) are hotspots of nutrient availability and primary
productivity in tropical savannas, creating spatial heterogeneity in
communities and ecosystem functions. These termites influence the local
availability of nutrients in part by redistributing nutrients across the
landscape, but the links between termite ecosystem engineering and the
soil microbes that are the metabolic agents of nutrient cycling are little
understood. We used DNA metabarcoding of soils from Odontotermes
montanus mounds to examine the influence of termites on soil
microbial communities in a semi-arid Kenyan savanna. We found that
bacterial and fungal communities were compositionally distinct in
termite-mound topsoils relative to the surrounding savanna, and that
bacterial communities were more diverse on mounds. The higher microbial
alpha and beta diversity associated with mounds created striking spatial
patterning in microbial community composition, and boosted landscape-scale
microbial richness and diversity. Selected enzyme assays revealed
consistent differences in potential enzymatic activity, suggesting links
between termite-induced heterogeneity in microbial community composition
and the spatial distribution of ecosystem functions. We conducted a
large-scale field experiment in which we attempted to simulate termites’
effects on microbes by fertilizing mound-sized patches; this altered both
bacterial and fungal communities, but in a different way than natural
mounds. Elevated levels of inorganic nitrogen, phosphorus, and potassium
may help to explain the distinctive fungal communities in termite-mound
soils, but cannot account for the distinctive bacterial
communities associated with mounds.