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bioRxiv · 10.1101/514083

Bacterial community changes with cryoconite granule size and their susceptibility to exogenous nutrients on 10 glaciers in northwestern Greenland

Uetake, J.·Nagatsuka, N.·Onuma, Y.·Takeuchi, N.·Motoyama, H.·Aoki, T.
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Abstract

Cryoconite granules, which are dark-colored biological aggregates on glaciers, effectively accelerate the melting of glacier ice. Bacterial community varies with granule size, however, community change in space and their susceptibility to environmental factors has not been described yet. Therefore, we focused on bacterial community from 4 different granule sizes (30-249 m, 250- 750 m, 750-1599 m, more than 1600 m diameter) in 10 glaciers in northwestern Greenland and their susceptibility for exogenous nutrients in cryoconite hole. A filamentous cyanobacterium Phormidesmis priestleyi, which has been frequently reported from glaciers in Arctic was abundant (10-26%) across any size of granules on most of glaciers. Bacterial community across glaciers became similar with size increase, and whence smallest size fractions contain more unique genera in each glacier. Multivariate analysis suggests that phosphate, which is significantly higher in one glacier (Scarlet Heart Glacier), is primary associated with bacterial beta diversity. Correlation coefficients between abundance of major genera and nutrients largely changed with granule size, suggesting that nutrients susceptibility to genera changes with growth process of granule (e.g. P. priestleyi was affected by nitrate in early growth stage).

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Uetake, J., Nagatsuka, N., Onuma, Y., Takeuchi, N., Motoyama, H., Aoki, T.. 2019-01-08. Bacterial community changes with cryoconite granule size and their susceptibility to exogenous nutrients on 10 glaciers in northwestern Greenland. https://doi.org/10.1101/514083

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