EPS Seminar Series: Dr. Richard LaBrie

Dr.  Richard LaBrie

Post-doctoral researcher working with Nagissa Mahmoudi

Department of Earth and Planetary Sciences, McGill University

12:00 - 13:00

FDA 232 (in-person) 

Pizza will be served

Marine bacteria as long-term sink of carbon and nitrogen

Abstract:

We live in a microbial world; global biogeochemical cycles are driven by microbial activity. In the oceans, the role of bacteria in the food chain has been recognized 50 years ago. By consuming dissolved organic matter produced by the primary producers (e.g., algae), they reintroduce part of the consumed carbon and nutrients into the food chain. However, this consumption is not perfect and they release a lot of CO2 when they respire, but also partially degraded molecules that can persist in the environment, a process referred to as the microbial carbon pump. As the marine dissolved organic matter pool is one of the most complex substances, understanding how some molecules persist is challenging. To do so, I use complementary approaches at the intersection between geochemistry and microbial ecology. In this presentation, I will talk about the role of marine heterotrophic bacteria in the cycling of dissolved organic carbon and nitrogen, and present two studies specifically on the role of bacteria as long-term sink of carbon and nitrogen.