Long-term forest soil warming alters microbial communities in temperate forest soils
DeAngelis, Kristen M.
Topcuoglu, Begum D.
van Diepen, Linda T. A.
Varney, Rebecca M.
Blanchard, Jeffrey L.
Melillo, Jerry M.
Frey, Serita D.
MetadataShow full item record
Soil microbes are major drivers of soil carbon cycling, yet we lack an understanding of how climate warming will affect microbial communities. Three ongoing field studies at the Harvard Forest Long-term Ecological Research (LTER) site (Petersham, MA) have warmed soils 5°C above ambient temperatures for 5, 8, and 20 years. We used this chronosequence to test the hypothesis that soil microbial communities have changed in response to chronic warming. Bacterial community composition was studied using Illumina sequencing of the 16S ribosomal RNA gene, and bacterial and fungal abundance were assessed using quantitative PCR. Only the 20-year warmed site exhibited significant change in bacterial community structure in the organic soil horizon, with no significant changes in the mineral soil. The dominant taxa, abundant at 0.1% or greater, represented 0.3% of the richness but nearly 50% of the observations (sequences). Individual members of the Actinobacteria, Alphaproteobacteria and Acidobacteria showed strong warming responses, with one Actinomycete decreasing from 4.5 to 1% relative abundance with warming. Ribosomal RNA copy number can obfuscate community profiles, but is also correlated with maximum growth rate or trophic strategy among bacteria. Ribosomal RNA copy number correction did not affect community profiles, but rRNA copy number was significantly decreased in warming plots compared to controls. Increased bacterial evenness, shifting beta diversity, decreased fungal abundance and increased abundance of bacteria with low rRNA operon copy number, including Alphaproteobacteria and Acidobacteria, together suggest that more or alternative niche space is being created over the course of long-term warming.
© The Author(s), 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Frontiers in Microbiology 6 (2015): 104, doi:10.3389/fmicb.2015.00104.
The following license files are associated with this item:
Showing items related by title, author, creator and subject.
Steeper declines in forest photosynthesis than respiration explain age-driven decreases in forest growth Tang, Jianwu; Luyssaert, Sebastiaan; Richardson, Andrew D.; Kutsch, Werner; Janssens, Ivan A. (2014-04)The traditional view of forest dynamics originated by Kira, Shidei, and Odum suggests a decline in net primary productivity (NPP) in ageing forests due to stabilized gross primary productivity (GPP) and continuously increased ...
Long-term CO2 enrichment of a forest ecosystem : implications for forest regeneration and succession Mohan, Jacqueline E.; Clark, James S.; Schlesinger, William H. (Ecological Society of America, 2007-06)The composition and successional status of a forest affect carbon storage and net ecosystem productivity, yet it remains unclear whether elevated atmospheric carbon dioxide (CO2) will impact rates and trajectories of forest ...
Ducklow, Hugh W. (Inter-Research, 2008-09-18)Bacteria, archaea and other microbes have dominated most biogeochemical processes on Earth for >99% of the history of life, but within the past few decades anthropogenic activity has usurped their dominance. Human activity ...