Potential carbon mineralization of permafrost peatlands in Great Hing'an Mountains, China

Peatlands play a significant role in global carbon (C) cycles. Through incubation experiments of peat samples selected in the discontinuous permafrost zone of the Great Hing'an Mountains, we studied the effects of temperature and moisture on potential CO₂ emission. Rates of C mineralization decreased with soil depth, increased with temperature, and reached the highest rates at 60% WHC (water holding capacity) at the same temperature. Total C mineralization ranged from 10.3 to 95.0 mg under the treatments for 40 d incubation and was significantly affected by soil temperature and moisture (P∈<∈0.001). Calculated Q ₁₀ values ranged from 2.1 to 2.7, and the average values could be used for multiple regression functions. We successfully predicted C mineralization as a function of incubation time, temperature, and moisture (P∈<∈0.001) and estimated the peat C mineralization under future climate scenarios. The results indicated that C mineralization of peatlands would be accelerated under warming temperature. The peatlands in our study area would be a potential CO₂ source to the atmosphere with future climatic changes.