In Arctic soils, warming accelerates decomposition of organic matter and increases emission of greenhouse gases (GHGs), contributing to a positive feedback to climate change. Although microorganisms play a key role in the processes between decomposition of organic matter and GHGs emission, the effects of warming on temporal responses of microbial activity are still elusive. In this study, treatments of warming and precipitation were conducted from 2012 to 2018 in Cambridge Bay, Canada. Soils of organic and mineral layers were collected monthly from June to September in 2018 and analyzed for extracellular enzyme activities and bacterial community structures. The activity of hydrolases was the highest in June and decreased thereafter over summer in both organic and mineral layers. Bacterial community structures changed gradually over summer, and the responses were distinct depending on soil layers and environmental factors; water content and soil temperature affected the shift of bacterial community structures in both layers, whereas bacterial abundance, dissolved organic carbon, and inorganic nitrogen did so in the organic layer only. The activity of hydrolases and bacterial community structures did not differ significantly among treatments but among months. Our results demonstrate that temporal variations may control extracellular enzyme activities and microbial community structure rather than the small effect of warming over a long period in high Arctic soil. Although the effects of the treatments on microbial activity were minor, our study provides insight that microbial activity may increase due to an increase in carbon availability, if the growing season is prolonged in the Arctic.
|Number of pages||14|
|Publication status||Published - 2022 Jul|
Bibliographical noteFunding Information:
The authors appreciate the support of the Korea Polar Research Institute and National Research Foundation of Korea.
This study was supported by the Ministry of Education of Korea (NRF-2019H1A2A1076239; Global Ph.D. Fellowship Program) and the Ministry of Science and ICT of Korea (NRF-2016M1A5A1901795, NRF-2016M1A5A1901770, PN20081 NRF-2018K2A9A1A01090455, NRF-2020R1I1A2072824 and NRF-2020M1A5A1110494).
© 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.
All Science Journal Classification (ASJC) codes
- Ecology, Evolution, Behavior and Systematics
- Soil Science