Soil CO2-fixation by cbbL-harboring microorganisms in different types of permafrost peatlands

Permafrost peatlands serve as crucial reservoirs of soil carbon (C). However, the mechanisms of microbial-driven soil C fixation in different types of permafrost peatlands are unclear. In this study, microbial C-fixation rate and carbon-fixation microbial community in different soil layers of continuous permafrost (CP), discontinuous permafrost (DP), and seasonal frozen (SF) peatlands were investigated using 13C isotopic labeling and DNA stable isotope probing (13C-DNA-SIP) techniques. The measured microbial C-fixation rates were in the range of 0.05 to 0.74 mg C m-2 day-1.