Broad-scale predictability of carbohydrates and exopolymers in Antarctic and Arctic sea ice

Graham J. C. Underwood, Shazia N. Aslam, Christine Michel, Andrea Niemi, Louiza Norman, Klaus M. Meiners, Johanna Laybourn-Parry, Harriet Paterson, David N. Thomas

Research output: Contribution to journalArticlepeer-review

41 Citations (Scopus)

Abstract

Sea ice can contain high concentrations of dissolved organic carbon (DOC), much of which is carbohydrate-rich extracellular polymeric substances (EPS) produced by microalgae and bacteria inhabiting the ice. Here we report the concentrations of dissolved carbohydrates (dCHO) and dissolved EPS (dEPS) in relation to algal standing stock [estimated by chlorophyll (Chl) a concentrations] in sea ice from six locations in the Southern and Arctic Oceans. Concentrations varied substantially within and between sampling sites, reflecting local ice conditions and biological content. However, combining all data revealed robust statistical relationships between dCHO concentrations and the concentrations of different dEPS fractions, Chl a, and DOC. These relationships were true for whole ice cores, bottom ice (biomass rich) sections, and colder surface ice. The distribution of dEPS was strongly correlated to algal biomass, with the highest concentrations of both dEPS and non-EPS carbohydrates in the bottom horizons of the ice. Complex EPS was more prevalent in colder surface sea ice horizons. Predictive models (validated against independent data) were derived to enable the estimation of dCHO concentrations from data on ice thickness, salinity, and vertical position in core. When Chl a data were included a higher level of prediction was obtained. The consistent patterns reflected in these relationships provide a strong basis for including estimates of regional and seasonal carbohydrate and dEPS carbon budgets in coupled physical- biogeochemical models, across different types of sea ice from both polar regions.

Original languageEnglish
Pages (from-to)15734-15739
Number of pages6
JournalProceedings of the National Academy of Sciences of the United States of America
Volume110
Issue number39
DOIs
Publication statusPublished - 24 Sep 2013
Externally publishedYes

Fingerprint

Dive into the research topics of 'Broad-scale predictability of carbohydrates and exopolymers in Antarctic and Arctic sea ice'. Together they form a unique fingerprint.

Cite this