Unveiling the role of bioturbation on bacterial activity in metal-contaminated sediments by Microcomputed tomography and Synchrotron-based 2D μXR

with Simone Pennafirme

440 Goodwin Hall
Thursday, February 10, 3:30 PM to 5:00 PM
Hosted by Juliana P. Duarte

Interactions among macrofauna, biogeochemistry, and microbiology of marine sediments are essential for the full functioning of benthic marine ecosystems. The biogenic structures of macrofauna (such as galleries, tunnels, burrows) and interactions among organisms are of great relevance in studies aimed at understanding ecological processes in sedimentary environments. The modalities of benthic animal activities reflect on the interaction with the sediment and its associated microorganisms. The trophic mode of bioturbation benthic fauna is essential since this controls the gallery structure and irrigation rate, which, in its turn, affects the composition of the microbial communities and associated biogeochemical processes. The interaction between micro- and macrofauna often impacts sedimentary processes, including transport, solutes flow, and remineralization of organic matter. In contaminated areas, contaminant mobilization may also occur, altering the behavior of metals in sediments and microbial communities. These activities, in many cases, result in both positive and negative feedback controls on the fauna itself. Although it is known that bioturbation affects microbial communities and that bacteria, in its turn, have strategies to immobilize contaminants, little is known about the mechanisms behind these interactions. New and creative interdisciplinary research is needed to address the empirical challenges of discerning the connection between bioturbation, bacterial assemblages, and the integrity of ecosystem function in environments contaminated by metals. Microcomputed tomography and Synchrotron-based 2D μXR, associated with biomarkers and biological analysis, have a significant potential for unveiling ecosystems’ marine processes and functioning.

Simone Pennafirme is a PostDoc Researcher at the Nuclear Engineering Program at UFRJ / POLI / COPPE, supervised by Professor Lima. Dr. Pennafirme has a Ph.D. in Marine Biology from the Graduate Program at UFF. Part of Dr. Pennafirme’s thesis was carried out at the Nuclear Engineering Program/COPPE-UFRJ and the National Synchrotron Light Laboratory (LNLS-CNPEM). Dr. Pennafirme is interested in Marine Microbiology Ecology, working mainly on the interaction between Macro- and Microorganisms, focusing on bacterial biofilm and the use of Biomarkers and Nuclear Techniques (µCT, XRF, and SRµXRF) as investigation tools.