As a zonal phenomenon of soil heat dynamics in high latitude and high altitude areas, freeze-thaw cycle strongly affects soil microbial process, which has attracted more and more attentions in recent years. However, there are few studies on the effects of different stages of freeze-thaw cycle on the composition and function of soil microbial community.
Researchers from the Institute of Applied Ecology of the Chinese Academy of Sciences conducted in-situ freeze-thaw experiment in a mixed broad-leaved Korean pine forest in Changbai Mountain. They divided the freeze-thaw process into three stages (frozen stage, initial freeze-thaw stage and continuous freeze-thaw stage) to monitor changes in the composition and function of soil microbial communities.
According to the researchers, bacteria are more sensitive to freeze-thaw cycle than fungi, and the freeze–thaw stage has no significant effect on fungal biomass, diversity and community composition.
They further found moderate initial freeze–thaw increase bacterial biomass, diversity and copiotrophic taxa abundance, while subsequent continuous freeze-thaw reduce bacterial biomass and diversity.
In addition, changes of bacterial community composition and diversity during freeze-thaw cycle are mainly caused by the changes of soil water content, dissolved organic carbon, ammonium nitrogen and total dissolved phosphorus.
This study has been published in Ecological Processes entitled "Responses of soil microbial communities to freeze-thaw cycles in a Chinese temperate forest."
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