Lee Karp-Boss and Emmanuel Boss, professors in the Faculty of Marine Sciences at the University of Maine, took a month-long research cruise to the western South Atlantic Ocean as part of the Mission Microbiomes project of the Tara Ocean Foundation.

Tara, a French association that leads oceanic expeditions using its titular research schooner, launched the project in December 2020 to learn more about how marine microbiomes, or assemblages of microorganisms, work in a given ocean environment. The organization also aims to understand how climate change and plastic pollution affect marine microbiomes.

Microbiomes make up two-thirds of marine biomass, support an extensive food chain, and play an important role in biogeochemical cycles, but little is known about their inner workings, according to Tara.

Boss and Karp-Boss joined the schooner Tara at the start November for part of the two-year 40,000 mile journey along the African, South American and Antarctic coasts. Along with other Brazilian researchers, they designed and sampled various oceanographic regimes in sub-sampled regions of Brazilian waters.

Funded by a grant from the National Aeronautics and Space Administration (NASA), Karp-Boss and Boss also installed the latest generation of oceanic instruments on the research vessel to study plankton, tiny single-celled organisms that are the basis of the aquatic food chain, and their associated optical properties.

The new instruments include two sensors recently developed at Sequoia Scientific Inc. by, among others, Wayne Slade and Thomas Leeuw, two former students of the UMaine School of Marine Sciences, to measure hyperspectral backscatter and polarized angular scattering. These instruments provide information on the size and composition of ocean particles, link them to Ocean Color remote sensing – an area of ​​interest to NASA – and provide a unique view of the organisms that make up plankton. UMaine researchers have also installed a plankton imaging sensor called Imaging Flow Cytobot, which allows scientists to detect changes in the composition of the plankton community “in flight”.

In addition to conducting research, Boss and Karp-Boss participated in several outreach activities in several Brazilian cities, including Rio de Janeiro, Santos and Itajaí, and in Buenos Aires, Argentina, where their leg of the journey ended. . They met school-aged children and members of the general public who visited the schooner and participated in scientific meetings to develop new collaborations with scientists from Brazil and Argentina. They also attended a ceremony in Santos, Brazil, in which city officials signed a law requiring the inclusion of ocean literacy in public school curricula, the first of its kind in the world. .

Karp-Boss and Boss disembark from the research vessel in Buenos Aires. Guillaume Bourdin, doctoral student at the School of Marine Sciences at UMaine, replaced them for the next stage of the Microbiomes mission from Buenos Aires to Ushuaia, Argentina, which will focus on coccolithophoric blooms in the Malvinas Current. Coccolithophores are algae responsible for massive blooms culminating in geological features such as the White Cliffs of Dover, England. Other current and past UMaine students and affiliates are expected to board the ship along its route to South Africa and along the African coast to its home port in Lorient, where it will arrive. in October 2022. More information about the trip can be found on the Tara Ocean Foundation website.

Contact: Marcus Wolf, 207.581.3721; [email protected]