Dataset Information

In situ response of Antarctic under-ice primary producers to experimentally altered pH.

ABSTRACT: Elevated atmospheric CO₂ concentrations are contributing to ocean acidification (reduced seawater pH and carbonate concentrations), with potentially major ramifications for marine ecosystems and their functioning. Using a novel in situ experiment we examined impacts of reduced seawater pH on Antarctic sea ice-associated microalgal communities, key primary producers and contributors to food webs. pH levels projected for the following decades-to-end of century (7.86, 7.75, 7.61), and ambient levels (7.99), were maintained for 15?d in under-ice incubation chambers. Light, temperature and dissolved oxygen within the chambers were logged to track diurnal variation, with pH, O₂, salinity and nutrients assessed daily. Uptake of CO₂ occurred in all treatments, with pH levels significantly elevated in the two extreme treatments. At the lowest pH, despite the utilisation of CO₂ by the productive microalgae, pH did not return to ambient levels and carbonate saturation states remained low; a potential concern for organisms utilising this under-ice habitat. However, microalgal community biomass and composition were not significantly affected and only modest productivity increases were noted, suggesting subtle or slightly positive effects on under-ice algae. This in situ information enables assessment of the influence of future ocean acidification on under-ice community characteristics in a key coastal Antarctic habitat.

SUBMITTER: Cummings VJ

PROVIDER: S-EPMC6465331 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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In situ response of Antarctic under-ice primary producers to experimentally altered pH.

Cummings Vonda J VJ Barr Neill G NG Budd Rod G RG Marriott Peter M PM Safi Karl A KA Lohrer Andrew M AM

Scientific reports 20190415 1

Elevated atmospheric CO<sub>2</sub> concentrations are contributing to ocean acidification (reduced seawater pH and carbonate concentrations), with potentially major ramifications for marine ecosystems and their functioning. Using a novel in situ experiment we examined impacts of reduced seawater pH on Antarctic sea ice-associated microalgal communities, key primary producers and contributors to food webs. pH levels projected for the following decades-to-end of century (7.86, 7.75, 7.61), and am ...[more]

PMID: 30988340

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Dataset Information

In situ response of Antarctic under-ice primary producers to experimentally altered pH.

Publications

In situ response of Antarctic under-ice primary producers to experimentally altered pH.

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