Dynamics of 'Glacier Blood' microbial ecosystems in the European Alps

Mountain environments are home to extremophilic terrestrial microalgae that become loaded with pigments to protect them from strong light conditions. The red staining of snow and ice surfaces characteristic of such microbial activity (known as 'glacier blood') is now noticeably more frequent and widespread at high altitudes globally and is

evidence that warming is impacting mountain ecology at the most fundamental of levels. Although algae residing within the surface of high-latitude ice masses are now well- known to play globally significant roles in biogeochemical cycling and ice-albedo feedbacks, the distribution, diversity, and function of algal communities specific to alpine regions

has been poorly studied, meaning little is understood regarding their origin and dynamics, means of production, and impact on carbon cycling and glacier melt. Objectives 1. Apply Earth Observation tools to quantify algal spatial and temporal dynamics on snow and ice surfaces 2. Undertake field sampling of snow and ice surfaces and

melt products 3. Apply metagenomic and metaproteomic analyses to samples to elucidate ecosystem composition and function 4. Quantify the sources and fluxes of carbon at the catchment scale and the contribution from snow- and ice- surface ecosystems Novelty & timeliness Algae affect and are affected by environmental warming

and expansion of algal communities at high elevation has potentially destablising consequences for mountain ecosystems and ice bodies. This project will couple Earth Observation approaches that will quantify algal community expansion at the Alpine scale with plot- and catchment- level sampling to enable: (a) metagenomic and

metaproteomic analyses that will establish microbial community composition, processes and metabolic pathways; and (b) carbon quality and carbon isotope analysis that will quantify carbon fluxes from biological and geological sources. This novel suite of methods aims to provide unique insight into algal community functioning and

dynamics and their role in biogeochemical processes that sequester atmospheric CO2.