The Black Sea is the largest known oxygen-depleted, sulfide-enriched basin on Earth. Although hydrogen sulfide is usually toxic, oxygen-depleted marine waters rich in sulfide can have surprisingly high densities of eukaryotic microorganisms (e.g., foraminiferans). This modest NSF award will support work on a single research collecting cruise in the southwestern Black Sea to explore microbial communities at points where the sediment/water interface intersects with the disappearance of oxygen in the water column. Populations of eukaryotic microbes will be quantified and characterized, as well as examined for the presence of symbiotic bacteria. Environmental conditions will be determined by using chemical data that will be collected from the same samples (as part of other NSF projects, G. Luther, University of Delaware). Results will provide a view of what may be a very unique bottom-dwelling Black Sea microbial community, with many organisms previously unknown to science, thereby providing a foundation for future, more multidisciplinary detailed studies in the area.
Oxygen depletion caused by human activities is becoming more widespread in marine waters. Characterizing microbial consortia in the Black Sea may lead to a better understanding of the role of these communities in other waters where the process is less desirable, and could suggest new remedies. Other broader impacts of this project include the involvement of an undergraduate student from an institution in an EPSCoR state, and interaction between the PI and possible foreign collaborators. Results will be integrated into coursework taught in future classes at the University of South Carolina.