Microbiome of a revegetated iron-mining site and pristine ecosystems from the Brazilian Cerrado

Abstract

The Cerrado domain is composed of different phytophysiognomies and considered a hot spot of global diversity. However, few studies have assessed the soil microbiome of this domain using metabarcoding approach. This study aimed to determine the soil microbiome in a mining site under revegetation and compare with communities of pristine ecosystems. Soil samples were collected in the dry and rainy seasons in an iron-mining site under revegetation (RA), semi-decidual forest (FL), canga (NG) and Cerrado stricto sensu (CE). Soil community was accessed by the amplification of the 16S and 18S ribosomal gene fragments using high-throughput sequencing. The prokaryotic operational taxonomic units (OTUs) were assigned to 18 phyla, 48 classes, 73 orders, 123 families and 168 genera. Acidobacteria and Proteobacteria were the most abundant phylum for FL, CE and RA while Actinobacteria and Acidobacteria were dominant in NG. Relative abundance of families within each phylum varied mainly among sites, but not seasons. For Eukarya, OTUs were assigned to 15 phyla, 35 classes, 94 orders, 168 families and 247 genera. Opisthokonta, SAR (Stramenopiles, Alveolates, and Rhizaria), and Archaeplastida were the most abundant groups for all phytophysiognomies and Fungi accounted for 51–71% of total sequences. Principal coordinate analysis indicates that soil community composition was not influenced by season within each site. We concluded that soil microbiome was dissimilar among sites at the family and genus level but sites shared the same dominant phyla, and that differentiation of soil microbiome was driven mainly by plant community composition.