Microbial activity in forest soil reflects the changes in ecosystem properties between summer and winter
Abstract
Understanding the ecology of coniferous forests is very important because these environments represent significant global carbon sinks. Metatranscriptomics, microbial community, and enzyme analyses were combined to describe the detailed role of microbial taxa in the functioning of the Picea abies-dominated coniferous forest soil in two contrasting seasons.
These seasons were the summer, representing the peak of plant photosynthetic activity, and late winter, after an extended period with no photosynthate input. The results show that microbial communities in soil and litter were highly diverse both in composition and function and characterized by a high abundance of fungi.
Differences in ecosystem functions between seasons consisted of a combination of moderate changes in microbial community composition and profound changes in taxon-specific microbial transcription profiles. Further, these differences were more significant in soil than in litter.
Most importantly, fungal contribution to total microbial transcription in soil decreased from 33% in summer to 16% in winter. In particular, the activity of abundant ectomycorrhizal was reduced in winter.
Overall, these results indicate that plant photosynthetic production was likely the major driver of changes in the functioning of microbial communities in this coniferous forest across seasons.