Microbial Diversity in Cerrado Biome (Neotropical Savanna) Soils

• Published in: PloS one 2016-02, Vol.11 (2), p.e0148785-e0148785
• Main Authors: de Castro, Alinne Pereira, Sartori da Silva, Maria Regina Silveira, Quirino, Betania Ferraz, da Cunha Bustamante, Mercedes Maria, Krüger, Ricardo Henrique
• Format: Article
• Language: English
• Subjects: Abundance; Archaea - classification; Archaea - genetics; Bacteria; Bacteria - classification; Bacteria - genetics; Bacteria - growth & development; Biodiversity; Biology and Life Sciences; Biomes; Brazil; Clay soils; Climate change; Communities; Deoxyribonucleic acid; DNA; Dormancy; Dry season; Earth Sciences; Ecology and Environmental Sciences; Ecosystems; Forest soils; Forests; Fungi; Fungi - classification; Fungi - genetics; Fungi - growth & development; Gene sequencing; Genes; Genetic testing; Grassland; Grasslands; Iron; Laboratories; Metabolism; Metagenome; Microbial activity; Microorganisms; Moisture content; Natural resources; Next-generation sequencing; Precipitation; Protein metabolism; Protein turnover; Rainy season; Relative abundance; Research and Analysis Methods; Ribonucleic acid; RNA; rRNA; Soil Microbiology; Soil moisture; Soil moisture variations; Soil water; Sporulation; Studies; Taxonomy; Temporal variations; Vegetation; Water stress; Water uptake
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0148785

The Cerrado, the largest savanna region in South America, is located in central Brazil. Cerrado physiognomies, which range from savanna grasslands to forest formations, combined with the highly weathered, acidic clay Cerrado soils form a unique ecoregion. In this study, high-throughput sequencing of ribosomal RNA genes was combined with shotgun metagenomic analysis to explore the taxonomic composition and potential functions of soil microbial communities in four different vegetation physiognomies during both dry and rainy seasons. Our results showed that changes in bacterial, archaeal, and fungal community structures in cerrado denso, cerrado sensu stricto, campo sujo, and gallery forest soils strongly correlated with seasonal patterns of soil water uptake. The relative abundance of AD3, WPS-2, Planctomycetes, Thermoprotei, and Glomeromycota typically decreased in the rainy season, whereas the relative abundance of Proteobacteria and Ascomycota increased. In addition, analysis of shotgun metagenomic data revealed a significant increase in the relative abundance of genes associated with iron acquisition and metabolism, dormancy, and sporulation during the dry season, and an increase in the relative abundance of genes related to respiration and DNA and protein metabolism during the rainy season. These gene functional categories are associated with adaptation to water stress. Our results further the understanding of how tropical savanna soil microbial communities may be influenced by vegetation covering and temporal variations in soil moisture.