Biodiversity and function of bacteria in the Southern Ocean

Abstract

A short overview of the biodiversity of Antarctic marine bacteria is given with respect to morphology and metabolic activity. The importance of spatial and temporal variability is described. The physiological adaptation and ecological function of Antarctic marine bacterioplankton are discussed.

Plankton Structure of Shallow Coastal Zone at Admiralty Bay, King George Island, West Antarctic Peninsula (Wap) During Early Summer/2010: Pico, Ultra and Microplankton and Chlorophyll Biomass

“…The West Antarctic Peninsula (WAP) waters undergo extreme seasonal uctuations in terms of light regime, seaice concentration and productivity (Delille, 2004). e WAP has experienced a signi cant rise in air temperatures during the last 50 years (±0.56 °C per decade; Marshall et al, 2002).…”

Pseudoalteromonas prydzensis sp. nov., a psychrotrophic, halotolerant bacterium from Antarctic sea ice

“…Bacteria concentrate in diatom assemblages which occur either as surface populations, internal band assemblages, or at the sea ice/seawater interface (Palmisano & Garrison, 1993). The majority of the bacterial populations in sea ice assemblages are psychrophilic (Bowman et al, 1997c;DeLille, 1996). In seawater underlying sea ice the presumable lack of nutrients, lack of surfaces or stable matrices for colonization prevents the establishment of psychrophilic populations even though the temperature is comparable to that of the lower sections of sea ice (about -2 "C).…”

“…Psychrotrophic bacteria predominate in under-ice seawater, however compared to popu- lations in sea ice assemblages their activity and productivity is low. Psychrotrophic bacterial species appear to be as common in sea ice as in the underlying seawater (Bowman et al, 1997c;DeLille, 1996; Helmke & Weyland, 1995) with Pseudoalteromonas strains being the most frequently isolated psychrotroph (Bowman et al, 1997a, c).Most probable number (MPN) counting was used to determine the viable heterotrophic bacterial count for sea ice and underlying seawater samples at incubation temperatures of 2 and 25 "C (Bowman et al, 1997b). Colonies of Pseudoalteromonas-like strains were frequently isolated from the highest positive dilution incubated at 25 "C (77 % of all samples) of both sea ice and seawater samples.…”

Microplankton Community Structure of the Shallow Coastal Zone at Admiralty Bay, Antarctica: Comparison Between Two Consecutive Austral Summers

“…Marshall et al, 2002;Delille, 2004;Moline et al, 2004;Montes-Hugo et al, 2009). In this context, a monitoring program to study the planktonic biodiversity in shallow waters (<30m) at Admiralty Bay was implemented in 2002 by PROANTAR (Brazilian Antarctic Program) aiming to study the effects of environmental impacts (natural and anthropogenic) on the microplanktonic community structure, through the analysis of long-term time series.…”