The role of foraminifera in Antartic Benthic communities with respect to the seasonal deposition of organic matter

• Main Author: Suhr Sliester, Stephanie B
• Format: Thesis
• Language: English
• Published: University of Southampton 2003
• Subjects: Antarctic; The Antarctic; Antarctic Peninsula; McMurdo Sound; Anvers; Anvers Island; Arthur Harbor; Explorers Cove; Antarc*; antartic*; Sea ice
• Online Access: https://eprints.soton.ac.uk/465049/; https://eprints.soton.ac.uk/465049/1/906238.pdf

Antarctic marine environments are characterised by intense seasonality. High nutrient concentrations in seasonally ice covered Antarctic coastal and shelf areas lead to a massive phytoplankton bloom following the melting of the sea ice in spring and early summer. A major part of this particulate organic material can be deposited on the seafloor, where it is available as food for the benthic community. The seasonality of nutrient input is probably the most significant ecological feature in Antarctic shelf environments. Foraminifera often represent a substantial proportion of the abundance and biomass of benthic communities in polar environments, where they may contribute significantly to the benthic carbon cycle. The Antarctic Peninsula shelf, with its regular seasonal phytoplankton blooms and following organic matter deposition, represents a good opportunity to investigate the influence of pulsed food input on the benthic community and the role of foraminifera in these environments. This study examines benthic-pelagic coupling processes with a focus on foraminiferal and metazoan abundance and vertical distribution patterns at a study site on the Western Antarctic Peninsula shelf (FOODBANCS site A, 65°10’S, 64°46’W, near Anvers Island). In addition, aspects of foraminiferal feeding biology with respect to seasonal organic matter availability are investigated at three different sites around the Antarctic (Antarctic Peninsula shelf: FOODBANCS site A, Arthur Harbor: Anvers Island, Explorers Cove: McMurdo Sound), using fatty acid biomarker analysis, and the possible implications of the highly selective feeding displayed by some common species of foraminifera on Antarctic benthic communities are discussed. The results demonstrate that foraminifera and metazoans may respond in different ways to seasonal deposition of phytodetritus on the seafloor, and that foraminifera must be considered when studying benthic-pelagic coupling processes. Furthermore, it is important to consider different species of foraminifera ...