Role of Protists in Bacterial Carbon Decay in the Oceans
Abstract/Description/Artist Statement
Protists (single-celled eukaryotic microbes) are a diverse taxonomic group, with members filling multiple niches, including primary production, predation on bacteria, and direct consumption of dead particulate organic matter. Predatory protists are common, and they feed on bacteria, their presence may slow carbon remineralization by impeding decay by bacteria. On the other hand, modelling studies have found that protists may enhance bacterial decay through the release of nutrients that may stimulate bacterial activity. To better understand the effects protists produce on bacterial decay, several studies were conducted examining the effect under different conditions. In each of the experiments, particulate organic carbon (POC) decay was tracked using 14C radiolabelled algae.
Our results show that the effect on decay depended on the presence, abundance, size, and niche of the protist examined. Overall, however, and given natural abundances of heterotrophic protists, our experiments demonstrated a negligible effect of protists on decay rates simplifying parameterization of carbon flux models.
Faculty Advisor/Mentor
Alexander Bochdansky
Faculty Advisor/Mentor Email
abochdan@odu.edu
Faculty Advisor/Mentor Department
Oceanography
College/School Affiliation
College of Sciences
Student Level Group
Graduate/Professional
Presentation Type
Oral Presentation
Role of Protists in Bacterial Carbon Decay in the Oceans
Protists (single-celled eukaryotic microbes) are a diverse taxonomic group, with members filling multiple niches, including primary production, predation on bacteria, and direct consumption of dead particulate organic matter. Predatory protists are common, and they feed on bacteria, their presence may slow carbon remineralization by impeding decay by bacteria. On the other hand, modelling studies have found that protists may enhance bacterial decay through the release of nutrients that may stimulate bacterial activity. To better understand the effects protists produce on bacterial decay, several studies were conducted examining the effect under different conditions. In each of the experiments, particulate organic carbon (POC) decay was tracked using 14C radiolabelled algae.
Our results show that the effect on decay depended on the presence, abundance, size, and niche of the protist examined. Overall, however, and given natural abundances of heterotrophic protists, our experiments demonstrated a negligible effect of protists on decay rates simplifying parameterization of carbon flux models.