Investigating microbial communities that exist in various nooks and crannies of both terrestrial and aquatic ecosystems is much like exploring outer space. The microbial universe on this planet is a great unknown. In fact, researchers suspect that only less than 1% of all microorganisms have been identified and documented. Microbial communities play a variety of essential roles, in particular, in complex geochemical processes of global elemental cycling. The mystery of the microbial world in terms of identifying who is out there (community structure) and what they are doing (community function) sparks my scientific curiosity.

My research questions explore the genetic diversity of microbial communities in biofilms that layer sediments and rock surfaces in Arctic stream systems of the Noatak National Preserve, Alaska. Biofilms are miniature landscapes. Interactions between geologic landforms, waterways, vegetation and animals comprise what we regard as a typical landscape; meanwhile bacteria, fungus, algae, enzymes and extracellular components interact on the whole as microbial landscapes. Both landscapes impart a certain geochemistry on one another and with the recent molecular techniques available, we can start to understand the interactions between large-scale and microbial landscapes at a fundamental level!

Studying microbial communities is also critical for understanding the function of delicate Arctic ecosystems. Moreover, given the recent effects of global climate change and the observed amplified changes in Arctic regions, microbial communities may be used as sensitive indicators of how these changes may alter geochemical cycling both on ecosystem and global scales.

These two landscapes at their own relative scales may very well impact each other!





Microbes that live in the permafrost may be activated with increased melting of the permafrost in Arctic Alaska. Will increased microbial activity of recently exposed microbes (e.g. those that give off methane) affect the delicate balance of geochemical cycling?



Story by: Julia Larouche
Masters Student, University of Vermont