Metagenomic sequencing of South Korean forest soils reveal plant host and spatially mediated microbial structure

Background/Question/Methods

Plant species, as well as biogeochemical traits, are major mediators of microbial diversity in forest ecosystem soils.  The effect of both host and nutrient concentration has been difficult to measure in forest soils because microbial diversity is largely unculturable and difficult to discern.  New sequencing technologies have drastically influenced our ability to address microbial ecology in soils.  In an attempt to observe host effects on forest soil microbial diversity, we studied research forest sites with a long history of recorded natural history and geochemical data within South Korea.  These forests were clear-cut during Japanese occupation during WWII and subsequently reforested and managed.  This dramatic history of forests in South Korea provides a unique opportunity to address the role of tree host in mediating microbial diversity.

Results/Conclusions

In order to address soil microbial diversity host-tree affects, we assessed microbial diversity in five forested plots in South Korea. Using metagenomic shotgun sequencing of total DNA from soils in these forest stands, we identified bacterial, archaeal, and eukaryotic taxa, notably fungal diversity.  Additionally, we addressed functional diversity in sequenced genes from each soil type.  We observed a similar general structure of microbial components in each forest soil.  However the data shows minute spatial and putative host-associated differences, particularly in the eukaryotic taxa that were identified.  While bacterial presence was fairly constant across all the sampled locations, eukaryotic diversity was spatially patchy.