title: Distinct bacterial communities across a gradient of vegetation from a preserved Brazilian Cerrado.
abstract: The Cerrado biome in the Sete Cidades National Park, an Ecological Reserve in Northeastern Brazil, has conserved its native biodiversity and presents a variety of plants found in other savannas in Brazil. Despite this finding the soil microbial diversity and community structure are poorly understood. Therefore, we described soil bacterial diversity and distribution along a savanna vegetation gradient taking into account the prevailing environmental factors. The bacterial composition was retrieved by sequencing a fragment of the 16S ribosomal RNA gene. The bacterial operational taxonomic units (OTUs) were assigned to 37 different phyla, 96 classes, and 83 genera. At the phylum level, a core comprised by Proteobacteria, Acidobacteria, Actinobacteria, Firmicutes, Verrucomicrobia and Planctomycetes, was detected in all areas of Cerrado. 'Cerrado stricto sensu' and 'Cerradao' share more similarities between edaphic properties and vegetation and also present more similar bacterial communities, while 'Floresta decidual' and 'Campo graminoide' show the largest environmental differences and also more distinct bacterial communities. Proteobacteria (26%), Acidobacteria (21%) and Actinobacteria (21%) were the most abundant phyla within the four areas. All the samples present similar bacteria richness (alpha diversity) and the observed differences among them (beta diversity) were more related to the abundance of specific taxon OTUs compared to their presence or absence. Total organic C, N and P are the main abiotic factors structuring the bacterial communities. In summary, our findings show the bacterial community structure was clearly different across the Cerrado gradient, but that these environments share a bacterial phylum-core comprising Proteobacteria, Acidobacteria, Actinobacteria, Verrucomicrobia and Planctomycetes with other Brazilian savannas.
authors.affiliation: Soil Quality Laboratory, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil. asfaruaj@yahoo.com.br.
authors.forename: Ademir Sergio Ferreira
authors.initials: AS
authors.lastname: de Araujo
authors.affiliation: Laboratório de Ecologia Microbiana e Biotecnologia, Federal University of Ceara, Fortaleza, CE, Brazil.
authors.forename: Walderly Melgaço
authors.initials: WM
authors.lastname: Bezerra
authors.affiliation: Soil Quality Laboratory, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil.
authors.forename: Vilma Maria
authors.initials: VM
authors.lastname: Dos Santos
authors.affiliation: Soil Quality Laboratory, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil.
authors.forename: Sandra Mara Barbosa
authors.initials: SM
authors.lastname: Rocha
authors.affiliation: Soil Quality Laboratory, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil.
authors.forename: Nilza da Silva
authors.initials: ND
authors.lastname: Carvalho
authors.affiliation: Genome Laboratory, Agronomic Institute of Pernambuco, Recife, PE, Brazil.
authors.forename: Maria do Carmo Catanho Pereira
authors.initials: MD
authors.lastname: de Lyra
authors.affiliation: Genome Laboratory, Agronomic Institute of Pernambuco, Recife, PE, Brazil.
authors.forename: Marcia do Vale Barreto
authors.initials: MD
authors.lastname: Figueiredo
authors.affiliation: Genetic and Molecular Biology Laboratory, Agricultural Science Center, Federal University of Piauí, Teresina, PI, Brazil.
authors.forename: Ângela Celis
authors.initials: ÂC
authors.lastname: de Almeida Lopes
authors.affiliation: Laboratório de Ecologia Microbiana e Biotecnologia, Federal University of Ceara, Fortaleza, CE, Brazil.
authors.forename: Vania Maria Maciel
authors.initials: VM
authors.lastname: Melo
mesh_terms: D061271:Acidobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D039903:Actinobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D044822:Biodiversity; D001938:Brazil; D017753:Ecosystem; D000068536:Bacillota / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D061328:Planctomycetales / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D010944:Plants / Q000382:microbiology; D020560:Proteobacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012988:Soil Microbiology; D061327:Verrucomicrobia / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D012336:RNA, Ribosomal, 16S
keywords: 16S rRNA gene-based metagenomic; Brazilian savanna; Soil bacterial diversity