Snow Ecosystem: Microbial community structure and function in arctic snowpacks

Speaker: Dr. Lorrie Maccario, Ecole Centrale of Lyon (ECL)

Host: Head of Department, Professor Niels Kroer, Department of Biology

Abstract
The Arctic seasonal snowpack can extend at times over a third of the Earth’s land surface and 25 million square kilometers of sea ice over ocean surface. This chemically dynamic environment interacts with different environmental compartments such as the atmosphere, soil, sea ice and meltwater, and thus, strongly influences the entire biosphere.  While the snowpack appears to be a critical component of the cryosphere, it is disappearing. However, the perturbation of biological processes within the snowpack are rarely included in cryospheric climate change biological models, because snow as biological entity is largely underestimated. During the last few decades, snow microbial inhabitants have received an increasing interest and the view of snowpack as a biologically inert compartment has been challenged.  The main goal of my work is to investigate the snow as a functional ecosystem; i.e. a community of living organisms in conjunction with the non-living component of their environment and interacting as a system. In order to do so, microbial community taxonomic and functional composition of snow samples from different arctic snowpack models (e.g. seasonal snow from terrestrial fresh water snowpack (Ny-Ålesund, Svalbard) and sea ice snow cover (Nuuk, Greenland)) are analyzed using high throughput sequencing technologies. While numerous questions remain about microbial activity and complex community interactions, this work is a step to understanding the snow microbial processes, slow individually but likely not negligible on a global scale.