The Unseen Impacts of Human Footprints: How Land Use Reshapes Actinobacterial Communities in the Brazilian Cerrado

Evaluating microbial community changes in soils allows the understanding of ecoevolutionary dynamics, providing information on microbiome responses to anthropological interferences, reduced biodiversity, and climatic changes. The actinobacteria phylum plays crucial roles from an ecological point of view and is the focus of the present study, which tracked changes in the actinobacterial communities from Brazilian Cerrado soil in an environmental protection unit, based on different land uses. The evaluation of 16S rRNA and further taxonomical clustering of operational taxonomic units (OTUs) indicated Actinomycetales as the main order within all land uses, ranging from 45.4-70.1%, with Micrococales and Rubrobacterales being found only in agricultural soils. The evaluation of taxonomical classes revealed Actinobacteria as the main representative in all land uses (45.5-70.4%), with a paired coprevalence of Thermoleophilia (43.4%) in secondary soils, a taxon associated with phosphorus-deficient grounds. The unraveling of families and genera was most challenging due to the OTUs' dispersion given the volume of data, coupled with a high percentage of unidentified genera (71.6-86.1%), mainly in conserved and preserved areas. The reduced biodiversity, reduced undescribed taxa, and enhanced potentially pathogenic strains in anthropogenic affected sites, which suffer more from climatic changes, denote the harm that human activity causes to microbiological diversity.