Bacterial community shifts along the chronosequence in the Austre Lovenbreen glacier foreland, Svalbard

Abstract

We investigated the shift in bacterial community structure and soil development along a 100-year old chronosequence in the Austre Lovenbreen glacier foreland of Svalbard. Time after glacier retreat played a key role in determining bacterial community structure and soil development during succession. Environmental filtering (i.e., soil temperature) also accounted for a different, but substantial, proportion of the taxonomic and functional structure of bacterial communities. Average rRNA operon (rrn) copy number decreased over successional time, and there was a strong positive relationship between rrn copy number and metabolic functional diversity. This suggests that bacteria rapidly responding to nutrient availability may have the potential to adapt well to fluctuating environmental conditions by shifts in their cellular metabolism and physiology. Soil temperature is important in bacterial community assembly and functioning in deglaciated foreland. Trait-based studies have the potential to predict the responses of microbial communities to environmental change by linking the ecological strategies of soil microbes with ecosystem processes.