Effect of light, iron and vitamin B12 co-limitation on phytoplankton species of the Ross Sea (Antarctica). Ecological implications.

• Main Author: Bolinesi, Francesco
• Format: Doctoral or Postdoctoral Thesis
• Language: Italian; English
• Published: 2020
• Subjects: Antarctic; Ross Sea; Southern Ocean; The Antarctic; Antarc*; Antarctica
• Online Access: http://www.fedoa.unina.it/13159/; http://www.fedoa.unina.it/13159/1/bolinesi_francesco_32.pdf

This thesis aimed at understanding the ecophysiological mechanisms implied in primary production processes in the Ross Sea waters (Antarctica), addressing aspects related to structural and functional biodiversity of phytoplankton, their production efficiency and the limiting role of iron and vitamin B12 in determining rates and timing of production. The information gathered during this thesis has confirmed some fundamental points on which is based the present paradigm on the role of the primary component in structuring the Antarctic food web. The results obtained show a richer picture of production mechanisms, thanks to adequate scales covering the coupling between water and the different coastal features or with the open waters of the Southern Ocean. Diatoms and haptophytes represent the dominant groups of phytoplankton community, although new ecological evidence emerges from the research performed in situ and on phytoplankton species isolated and cultivated in laboratory under manipulative conditions (iron and vitamin B12 limitation). Data, in fact, highlight the necessity of looking to the significant contributor of heterotrophic pathways to autotrophic primary production processes in a changing Southern Ocean.