ORIGINAL RESEARCH article
Front. Microbiol.
Sec. Aquatic Microbiology
This article is part of the Research TopicMicrobial Diversity and Survival Strategies in Polar EnvironmentsView all 6 articles
Ecological Responses of Antarctic Chaetoceros spp. to Simulated Melting and Salinity Shifts
Provisionally accepted
- 1Department of Biology, Polytechnic and Basic Sciences School, University of Naples Federico II, Naples, Italy
- 2Consorzio Nazionale Interuniversitario per le Scienze del Mare, Rome, Italy
Select one of your emails
You have multiple emails registered with Frontiers:
Notify me on publication
Please enter your email address:
If you already have an account, please login
You don't have a Frontiers account ? You can register here
Climate-driven freshening and shifting sea-ice dynamics are altering surface salinity regimes in coastal Antarctic waters, with profound ecological consequences. Phytoplankton, as the foundation of polar marine food webs and a key driver of biogeochemical cycles, are particularly sensitive to salinity variability. In this study, we exposed a mixed Chaetoceros culture from Terra Nova Bay (Ross Sea) to a range of salinity conditions representative of both current microhabitats and projected future scenarios. By tracking short-term and acclimated responses across multiple functional traits— including photosynthetic efficiency, cell size and morphology, pigment composition, and nutrient uptake—we identified distinct acclimation strategies shaped by the severity and direction of salinity stress. These findings reveal how salinity fluctuations can restructure phytoplankton physiology in ways that influence trophic transfer efficiency, carbon export potential, and community resilience. For instance, shifts toward smaller, less pigmented cells under moderate hyposalinity may reduce food quality for grazers and alter energy flow through the food web, while extreme salinity events may favor microbial recycling over export. Moreover, salinity-driven changes in pigment:chlorophyll a ratios have implications for interpreting remote sensing data and chemotaxonomic reconstructions. By linking physiological plasticity to ecosystem-level processes, this study underscores the central role of salinity as an ecological filter in polar systems and highlights the need to incorporate salinity variability into models of phytoplankton dynamics and Southern Ocean biogeochemistry under climate change.
Keywords: Antarctic phytoplankton, Climate Change, functional traits, HPLC, Ross Sea
Received: 20 Nov 2025; Accepted: 30 Jan 2026.
Copyright: © 2026 Zigic, Mangoni, Serino and Bolinesi. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Olga Mangoni
Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.