The main primary producers on snow and ice surfaces are snow and ice algae, respectively. They are poly-extremophilic microalgae, which have evolved a range of adaptations to low temperature environments including the freezing of water, desiccation, nutrient deficiencies, and high light irradiation. In order to protect their photosystematic apparatus from photoinhibition, they produce a range of pigments, which cause distinct colourations of the snow and ice (e.g., green, red, brown, black). Together with other impurities (e.g., dust, minerals, black carbon), these algal-derived pigments cause a darkening of the snow and ice surfaces, which in turn decreases albedo and increases melt rates.
Yet, the biogeographic distribution patterns, their biodiversity and the biochemical strategies are still poorly understood. In order to get a better understanding, we are evaluating snow and ice algal communities, and their associated microbiome (i.e., bacteria, archaea, fungi), in various Arctic and Alpine settings by using a multi-disciplinary approach. We are conducting high-throughput sequencing to reveal community compositions and dynamics. The molecular findings are cross-correlated with the physico-chemical (e.g., pH) and geochemical (e.g., nutrients, trace metals) boundary conditions. Further, we are using a metabolomics approach to understand how their metabolome responds to changing environmental conditions.
Ongoing Project Collaborations:
REMACA - Radiocarbon estimates of microbial activity and carbon accumulation surrounding the Princess Elisabeth Station (REMACA)
This is a collaborative project with Dr. Lori Ziolkowski (University of South Carolina, USA), who was awarded the Baillet Latour Antarctica Fellowship to conduct field work in Antarctica in 2017 and 2018. Her project aims to use the natural abundance of radiocarbon to study the rates of carbon accumulation and microbial activity in a variety of habitats in Antarctica. Our contribution is the analysis of the microbial community compositions. The results will be coupled with the age estimates, to better characterize what microbes are active. For more information on this project, please visit http://www.science.loriz.ca/antarctica/ .
Arctic – Alpine comparison of snow algal communities
In collaboration with Dr. Daniel Remias (University of Applied Sciences Upper Austria, Wels), we are evaluating the geographic differences in the biodiversity of Alpine and Arctic snow communities. For more information on this project, please visit https://www.researchgate.net/project/Metabolomics-and-Biodiversity-of-Snow-and-Ice-Phototrophs
Black and Bloom – Understanding the melt of the Greenland Ice Sheet
This large NERC funded UK-led collaborative project aims to unravel how dark particles (black) and microbial processes (bloom) darken and accelerate the melting of the Greenland Ice Sheet. For more information on this project, please visit https://blackandbloom.org