Characterizing changes in soil bacterial community structure in response to short-term warming.
High altitude alpine meadows are experiencing considerably greater than average increases in soil surface temperature, potentially as a result of ongoing climate change. The effects of warming on plant productivity and soil edaphic variables have been established previously, but the influence of warming on soil microbial community structure has not been well characterized. Here, the impact of 15 months of soil warming (both +1 and +2 °C) on bacterial community structure was examined in a field experiment on a Tibetan plateau alpine meadow using bar-coded pyrosequencing. Warming significantly changed (P < 0.05) the structure of the soil bacterial community, but the alpha diversity was not dramatically affected. Changes in the abundance of the Actinobacteria and Alphaproteobacteria were found to contribute the most to differences between ambient (AT) and artificially warmed conditions. A variance partitioning analysis (VPA) showed that warming directly explained 7.15% variation in bacterial community structure, while warming-induced changes in soil edaphic and plant phenotypic properties indirectly accounted for 28.3% and 20.6% of the community variance, respectively. Interestingly, certain taxa showed an inconsistent response to the two warming treatments, for example Deltaproteobacteria showed a decreased relative abundance at +1 °C, but a return to AT control relative abundance at +2 °C. This suggests complex microbial dynamics that could result from conditional dependencies between bacterial taxa.
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, China; School of Marine Sciences, Ningbo University, Ningbo, China.
Jinbo
J
Xiong
Huaibo
H
Sun
Fei
F
Peng
Huayong
H
Zhang
Xian
X
Xue
Sean M
SM
Gibbons
Jack A
JA
Gilbert
Haiyan
H
Chu
D039903:Actinobacteria / Q000235:genetics*; D020561:Alphaproteobacteria / Q000235:genetics*; D044822:Biodiversity; D057232:Global Warming; D058889:Molecular Typing; D010944:Plants / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012988:Soil Microbiology
D012336:RNA, Ribosomal, 16S
Tibetan plateau; bacterial community; soil warming