Open AccessLong‐term warming alters the composition of A rctic soil microbial communities
Author(s) -
Deslippe Julie R.,
Hartmann Martin,
Simard Suzanne W.,
Mohn William W.
Publication year - 2012
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.2012.01350.x
Subject(s) - species evenness , tundra , microbial population biology , biology , ecology , ecosystem , nutrient cycle , dominance (genetics) , global warming , arctic , proteobacteria , climate change , species diversity , biochemistry , genetics , 16s ribosomal rna , bacteria , gene
Despite the importance of A rctic soils in the global carbon cycle, we know very little of the impacts of warming on the soil microbial communities that drive carbon and nutrient cycling in these ecosystems. Over a 2‐year period, we monitored the structure of soil fungal and bacterial communities in organic and mineral soil horizons in plots warmed by greenhouses for 18 years and in control plots. We found that microbial communities were stable over time but strongly structured by warming. Warming led to significant reductions in the evenness of bacterial communities, while the evenness of fungal communities increased significantly. These patterns were strongest in the organic horizon, where temperature change was greatest and were associated with a significant increase in the dominance of the A ctinobacteria and significant reductions in the G emmatimonadaceae and the P roteobacteria . Greater evenness of the fungal community with warming was associated with significant increases in the ectomycorrhizal fungi, R ussula spp., C ortinarius spp., and members of the Helotiales suggesting that increased growth of the shrub B etula nana was an important mechanism driving this change. The shifts in soil microbial community structure appear sufficient to account for warming‐induced changes in nutrient cycling in A rctic tundra as climate warms.