Abstract:
Polar Regions (continental Antarctica and the Arctic) are characterized by a
range of extreme environmental conditions, which impose severe pressures on biological
life. Polar cold-active cyanobacteria are uniquely adapted to withstand the environmental
conditions of the high latitudes. These adaptations include high ultra-violet
radiation and desiccation tolerance, and mechanisms to protect cells from freeze–thaw
damage. As the most widely distributed photoautotrophs in these regions, cyanobacteria
are likely the dominant contributors of critically essential ecosystem services, particularly
carbon and nitrogen turnover in terrestrial polar habitats. These habitats include
soils, permafrost, cryptic niches (including biological soil crusts, hypoliths and
endoliths), ice and snow, and a range of aquatic habitats. Here we review current
literature on the ecology, and the functional role played by cyanobacteria in various
Arctic and Antarctic environments. We focus on the ecological importance of
cyanobacterial communities in Polar Regions and assess what is known regarding the
toxins they produce. We also review the responses and adaptations of cyanobacteria to
extreme environments.
