Soil microbes and enzymes in permafrost peatland are sensitive to temperature changes, which might result in more potential loss of carbon and increase in available nitrogen from permafrost peatlands in a warming world. However, soil microbial abundance and enzymatic activity in permafrost peatlands under long-term climate warming is not well understood.
Researchers from the Northeast Institute of Geography and Agroecology of Chinese Academy of Sciences assessed the impact of long-term warming on soil microbial abundance and enzymatic activity in a permafrost peatland of northeastern China.
Results revealed that 6-year warming increased the abundance of bacteria in 0 to 15 cm soil under tussock and from shrub rhizosphere, fungi from shrub non-rhizosphere, and archaea under tussock and from the rhizosphere of shrub.
Six-year warming increased methanogen abundance in 0 to 15 cm soil and methanotroph abundance in 15 to 30 cm soil under tussock, indicating that warming could enhance CH4 cycling. Soil nirS-denitrifier abundance from the 0 to 15 cm shrub rhizosphere increased under warming, thereby suggesting that warming stimulated denitrification and N2O emission.
They found that β-glucosidase activity in 0 to 15 cm soil under tussock and from shrub rhizosphere increased, but invertase activity in 15 to 30 cm soil showed opposite tendency under warming.
Positive correlations between abundances of bacteria, archaea, contents of DOC, and NH4+–N in 0 to 15 cm soil suggest that increases in bacterial and archaeal abundance could indicate higher carbon and nitrogen availability in topsoil of permafrost peatlands under warming.
The results offer new insights into the response of plant-soil-microbe interactions in permafrost peatlands to climate change.
The research papers by SONG Yanyu, JIANG Lei, and SONG Changchun et al.werepublished in the journal of Ecological Indicators.