Seasonal observation of active later bacterial communities in Ny Alesund, Svalbard

The permafrost in the polar regions is vital for maintaining the status quo of the earth's climate by limiting greenhouse gas emissions. The top layer of permafrost that seasonally thaws during summer is called active layer (AL) permafrost. This study was carried out to understand the seasonal variations in bacterial diversity and communities of AL samples. The AL samples were collected from four different sites during winter and summer in Ny Alesund, Svalbard. Metagenomic DNA was isolated from AL samples and 16S rDNA amplicon sequencing targeting the V3 V4 region was carried out. Taxa abundance variation even at higher taxonomic levels was observed between seasons. The bacterial richness and diversity index were not significantly different between the winter and summer seasons. TN explained 25 % of bacterial community variation between seasons.

极地多年冻土（permafrost）通过抑制温室气体排放，对维持地球气候的稳态至关重要。夏季发生季节性融化的多年冻土层顶层，被称为活动层（active layer, AL）多年冻土。本研究旨在探究活动层冻土样本中细菌群落组成与多样性的季节变化规律。研究于斯瓦尔巴群岛的新奥尔松（Ny Alesund）开展，分别在冬季和夏季从四个不同采样点采集活动层冻土样本。从活动层冻土样本中提取宏基因组DNA，并针对V3-V4区开展16S rDNA扩增子测序。研究观察到，即使在高阶分类单元层面，不同季节间的类群丰度仍存在差异。冬季与夏季样本的细菌丰富度及多样性指数并无显著统计学差异。总氮（TN）可解释季节间25%的细菌群落变异。