Peatlands store one-third of the total global soil carbon despite covering only 3-4% of the global land surface. In recent hundreds years, the impact of global warming on permafrost thaws has even caused permafrost peatlands collapse and high amount of CO2 and CH4 emitted into atmosphere. Except climate change, wildfire also influences carbon dynamics in peatlands through direct burning of biomass or surface peat soils and with deposition of the fire products on the peatlands surface.
Carbon dynamic process and carbon stability in peatlands carbon pool are both important for researchers evaluating the impact of these environmental factors on peatlands carbon pool, several studies have already focused on the impact of historical climate change and regional human activities on the carbon dynamic process in these peatlands. While, the impact of these factors on the stability of peatlands carbon pool remains poorly understood.
The researchers from the Northeast Institute of Geography and Agroecology of the Chinese Academy of Sciences (IGA) selected five permafrost peatlands in northern Great Khingan Mountains, seriously affected by increasing temperature and high frequency wildfire in the last century, to reveal the impact of wildfire (indicated by pyrogenic carbon deposition fluxes) and global warming on the stability of the peatlands carbon pool (indicated by the carbohydrate and aromatic contents). These researches have been published on the Land Degradation & Development (https://onlinelibrary.wiley.com/doi/abs/10.1002/ldr.2837), and the Science of the Total Environment(https://www.sciencedirect.com/science/article/pii/S0048969719364721).
The results shown the mean July temperature was the most important climate factor for carbon stability in peatlands carbon pool. With the increasing of wildfire frequency and the residual wildfire products stored in peatlands carbon pool between 1900 and 1980, wildfire was the major factor that cause peatlands carbon pool more stable than other periods. After 1980, due to the wildfire controlled by local policies, increasing temperatures and decreasing precipitation became the major factors that increased carbon accumulation rates and the stability of peatlands carbon pool in northern Great Khingan Mountains, especially after 2000. “Our results suggested that global warming and high frequency wildfire could promote permafrost peatlands carbon pool more stable than before”, said Dr. GAO Chuanyu.
These work were supported by the National Key Research and Development Program, the National Natural Science Foundation of China, and the Jilin Provincial Joint Key Laboratory of Changbai Mountain Wetland and Ecology.
Dr. GAO Chuanyu
Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences
www.iga.ac.cn
Changchun, Jilin, 130102, China
Tel. 0431-85542274
E-mail: gaochuanyu@iga.ac.cn
Key words: permafrost peatlands, wildfire, carbon stability, climate change, mid-high latitude
