Effects of field warming on high arctic soil bacterial community: a metagenomic analysis

Soil microbial communities in the Arctic, one of the most rapidly warming regions on Earth, play an important role in a range of ecological processes. This report describes initial studies of natural soil bacterial diversity at a High Arctic site on Svalbard, as part of a long-term field environmental manipulation study. The impact of increased soil temperature and water availability on soil microbial communities was investigated. The manipulation experiment, using open-top chambers, was installed in late summer 2014, and the soils were sampled soon after snow melt in July 2015. High throughput sequencing of 16S rRNA genes showed relatively uniform diversity across the study area and revealed no significant initial effect of treatments on bacterial communities over the first 10-month autumn–winter–spring manipulation period

Effects of freeze-thaw cycles on High Arctic soil bacterial communities

The projected increase in freeze-thaw frequency associated with warmer temperatures in the High Arctic could affect the dynamics of soil bacterial communities. We report here the effects of freeze-thaw (FT) cycles on High Arctic bacterial communities of soil samples collected from three sites with different depths of snow cover. Analysis of 16S rRNA gene amplicon sequences showed that bacterial diversity in soil sampled under high snow cover were significantly different from those under low snow cover and those with no snow cover, and showed little change in community diversity after nine consecutive FT cycles. Conversely, bacterial diversity in soil samples under low and with no snow cover decreased after the simulated FT cycles. It is therefore likely that reduced snow cover will influence soil bacterial community structure through an increased frequency of freeze-thaw cycling