The effects of elevated CO 2 on soil bacterial community with upland vegetation have been widely studied, but limited information is available regarding responses of denitrifier and methanogen communities to elevated CO 2 in wetland ecosystems. Using restriction fragment length polymorphism (RFLP), terminal RFLP analysis, and real-time quantitative PCR, we compared communities of denitrifiers and methanogens in a laboratory-scale wetland system planted with one of three macrophytes, Typha latifolia, Scirpus lacustris, or Juncus effusus, after 110 days of incubation. Our study showed that elevated CO 2 could affect community structures of both denitrifiers and methanogens, each of which had a unique response pattern. In particular, elevated CO 2 shifted nirS-containing community with a unique structure irrespective of vegetation type. mcrA-containing community appeared to shift to community with unique types of hydrogenotrophs under elevated CO 2 conditions. The change of dissolved organic carbon driven by elevated CO 2 appeared to be related with the shift of both denitrifiers and methanogens. Overall, this study indicates that elevated CO 2 could change the community structure of denitrifiers and methanogens temporarily. These results also suggest a presence of stable dominant populations that were not substantially affected by changes in CO 2 concentration.
All Science Journal Classification (ASJC) codes
- Ecology, Evolution, Behavior and Systematics
- Soil Science