The Role of Microbial Ecology in Glacier Retreat

Glaciers have been considered too hostile to harbor life for a long time. However, they are now recognized as unique biomes dominated by microbial communities which maintain active biochemical routes. Microbial communities inhabiting glaciers are diverse depending on the type of glacier and the area studied. Some glaciers have a marine margin and finish in a calving front, with partly or completely temperate tidewater tongues, this establishes important differences with respect to glaciers with a land margin. Depending on the glacier area studied, microorganisms are also characteristic as they establish a vertical food chain, from the surface photosynthesizers in upper illuminated layers to heterotrophs confined in the inner part. Glaciers are retreating in many areas of the world due to global warming. Microorganisms are their most abundant and unknown occupants. They play a main role, carrying out key processes in the development of soil and facilitating plant colonization when glaciers have ultimately retired. These microorganisms are perfectly adapted to their harsh environment and are very susceptible to environmental changes. This chapter summarizes the role of microbial ecology as indicator of the conservation status of glaciers.