Tamanho da fonte: 

Miombo is the most extensive ecosystem in southern Africa, being strongly driven byfire, climate, herbivory, and human activity. Soils are major regulating and supporting services,sequestering nearly 50% of the overall carbon and comprising a set of yet unexploited functions.In this study, we used next-generation Illumina sequencing to assess the patterns of bacterial soildiversity in two pioneer Miombo species, Brachystegia boehmii and Brachystegia spiciformis, along a firegradient, in ferric lixisol and cambic arenosol soils. In total, 21 phyla, 51 classes, 98 orders, 193 families,and 520 genera were found, revealing a considerably high and multifunctional diversity with a strongpotential for the production of bioactive compounds and nutrient mobilization. Four abundant generacharacterized the core microbiome among plant species, type of soils, or fire regime: Streptomyces,Gaiella, Chthoniobacter, and Bacillus. Nevertheless, bacterial networks revealed a higher potentialfor mutualistic interactions and transmission of chemical signals among phylotypes from low firefrequency sites than those from high fire frequency sites. Ecological networks also revealed thenegative effects of frequent fires on the complexity of microbial communities. Functional predictionsrevealed the core “house-keeping” metabolisms contributing to the high bacterial diversity found,suggesting its importance to the functionality of this ecosystem.Keywords: Brachystegia; carbon; functional potential; legumes; metagenomics; rhizosphere; C and Nstable isotopes