Journal Article

Bacterial Community Composition and Diversity Respond to Nutrient Amendment but Not Warming in a Maritime Antarctic Soil

Yamamoto, Naomichi, Hopkins, David W., Dong, Ke, Adams, Jonathan M., Newsham, Kevin K., Tripathi, Binu M.

2019

Overview

A resumption of climate warming in maritime Antarctica, arising from continued greenhouse gas emissions to the atmosphere, is predicted to lead to further expansions of plant populations across the region, with consequent increases in nutrient inputs to soils. Here, we test the main and interactive effects of warming, applied with open top chambers (OTCs), and nutrient amendment with tryptic soy broth (TSB), an artificial growth substrate, on bacterial community composition and diversity using Illumina sequencing of 16S rRNA genes in soil from a field experiment in the southern maritime Antarctic. Substantial effects of TSB application on bacterial communities were identified after 49 months, including reduced diversity, altered phylogenetic community assembly processes, increased Proteobacteria-to-Acidobacteria ratios and significant divergence in community composition, notably increases in the relative abundances of the gram-positive genera Arthrobacter, Paeniglutamicibacter and Planococcus. Contrary to previous observations from other maritime Antarctic field warming experiments, we recorded no effects of warming with OTCs, or interactive effects of OTCs and TSB application, on bacterial community composition or diversity. Based on these findings, we conclude that further warming of the maritime Antarctic is unlikely to influence soil bacterial community composition or diversity directly, but that increased nutrient inputs arising from enhanced plant growth across the region may affect the composition of soil bacterial communities, with possible effects on ecosystem productivity.

• Publisher: Springer Science + Business Media,Springer US,Springer Nature B.V
• Subject: Antarctic region / Antarctic Regions / Antarctica / Arthrobacter / Bacteria / Bacteria - classification / bacterial communities / Bacterial Physiological Phenomena / Biomedical and Life Sciences / Climate change / Communities / Community composition / community structure / Composition / Divergence / Ecology / Ecosystem assessment / ecosystems / Emissions / Experiments / Fertilizers - analysis / field experimentation / Gene sequencing / genes / Geoecology/Natural Processes / Global Warming / Glucose / Gram-negative bacteria / Gram-positive bacteria / Greenhouse effect / greenhouse gas emissions / Greenhouse gases / Hot Temperature / Influence / Life Sciences / Microbial Ecology / Microbiology / Microbiota - drug effects / Mineral nutrients / Nature Conservation / Nutrients / Phylogenetics / Phylogeny / Plant growth / Plant population / Plant populations / Ratios / ribosomal RNA / RNA, Bacterial - analysis / RNA, Ribosomal, 16S - analysis / rRNA 16S / Science / sequence analysis / Soil / soil bacteria / SOIL MICROBIOLOGY / Soil microorganisms / Soil sciences / Soils / Substrates / Taxonomy / Water Quality/Water Pollution