Microbial carbon use efficiency rises after abrupt permafrost thaw, study finds

Décongélage of permafrost is a major climate risk due to the associated release of carbon dioxide and other greenhouse gases (GHG). However, new research by a team led by Professor Yang Yuanhe of the Botanical Institute of the Chinese Academy of Sciences shows how microbes can stabilize the carbon of the soil and potentially weaken climate risk.

In a new study published in Proceedings of the National Academy of SciencesResearchers provide convincing evidence that the effectiveness of the use of microbial carbon (CUE) – The proportion of carbon absorption used for microbial growth – is launching after a thaw of brutal pergialisol.

Using an independent substrate ¹⁸Approach to tracing O, the researchers examined how the microbial signal changes after a sudden thaw of permafrost. They collected samples of topsoil representing the Dégelisol – IE thawing sequence, the different phases of the thaw process – as well as samples of five additional sites assigned to the thaw on the Tibetan plateau.

The results of the Dégel sequence and regional sites have constantly revealed that the microbial signal increased after the thaw of permafrost, demonstrating the generality of the discovery.

A more in -depth analysis indicated that this microbial signal increase was largely driven by changes in the composition of microbial communities, including a higher fungal / bacterial biomass ratio and greater prevalence of rapid growth taxa in thawed soils. Increased availability of soil phosphorus during defrosting has also provided microbes with essential nutrients, thus supporting growth and improvement of the signal.

Traditionally, a sudden thawing thaw has been considered a major source of GHG emissions, accelerating carbon-climate comments. However, the observed increase in the microbial signal can promote the incorporation of microbial derivative compounds in the soil, promoting the stable soil carbon formation and potentially attenuating the intensity of carbon-climate feedback.

This study highlights the way in which the thaw of brutal permafrost affects the microbial signal and highlights the critical role of microbial physiology in determining the fate of the carbon of pergélisol.