Bacterial communities in the boreal forest soils with nitrogon and sulphur amendment

To improve the understanding of the boreal forest ecosystem response to N and S deposition in the AOSR, a stimulated deposition experiment was established in 2006. It was found that after 4-5 years of treatment soil microbial biomass carbon and nitrogen were not affected, and that after 5 years the soil microbial functional diversity and enzymatic activities were strongly affected (Jung and Chang 2012, Hu et al. 2013). In this study, we used pyrosequencing of 16S rRNA genes to determine the effects of N and S depositions on soil bacterial community diversity, composition, metabolism genes, and co-occurrence network. We hypothesize that (1) the overall diversity of bacteria species will decrease after N and S addition because it will favour species conditioned to thrive in N and S rich environments creating a narrow niche for microbial life and this will cause a change in species composition, (3) bacteria in treatments exposed to N and/or S will have functional gene profiles that focus on adaptation and metabolism genes that will utilize N and S as a source of viability when compared to the control, and (4) the number of interactions will be lower in the treatment sites when compared to the control because the depositions will create more confined niches for bacteria and thus limiting their intra and interspecies interaction. N and S deposition have a wide range of effects that can include fertilization but also acidification; therefore, it is an important issue that is of concern not only to the government and industry but also to the public