Researchers of the P. P. Shirshov Institute of Oceanology of the Russian Academy of Sciences, subordinate to the Ministry of Education and Science of the Russian Academy of Sciences, completed work off the coast of Brazil at the mouth of the Amazon, which took place as part of the 52nd voyage of the expedition of the Research vessel “Academician Boris Petrov”. According to the results of the research, the participants were able to determine how plastic garbage gets into the World Ocean from the mouth, according to a press release from the Ministry of Education and Science.
This is the second case in history when a Russian scientific vessel enters the Amazon for the purpose of conducting scientific research. The first such expedition took place in 1983 on board the research vessel “Professor Shtokman” under the leadership of Academician Andrey Monin. Then scientists examined samples of sea suspension and solid sediments from the waters of the Amazon.
This year it was decided to repeat similar studies with the help of modern devices. The work was carried out in the largest river plume (desalinated water mass) The world Ocean, on the shelf of the northern part of Brazil near the mouth of the Amazon River.
Measurements performed at 28 stations included CTD-sounding (measurement of electrical conductivity, temperature, pressure) and sampling of water from various horizons, zooplankton and phytoplankton, as well as collecting microplastic samples.
As you know, the Amazon is the largest source of plastic waste entering the ocean, but the mechanism of plastic distribution in the Amazon plume has not been fully studied. Scientists paid attention to the general picture of plastic pollution of the coast, landscapes that contribute to the accumulation of plastic debris to varying degrees, the origin of macroplastic and its typification, collecting samples of overgrown plastic to analyze the structure of microplaston, as well as phytoplankton catches and soil sampling for analysis.
They also studied eight areas of the coastal zone, significantly spaced across the terrain and differing in the degree of anthropogenic (human activity-related) load.
Preliminary results showed that over 80% of macroscopic plastic garbage on the Atlantic coast in the studied areas is disposable packaging (PET bottles, bags and foam). Experts concluded that most of this garbage is brought by the river through estuarine zones of individual delta channels from ports, settlements and large settlements located higher up the river.
About 90% of the labelled plastic is of local Brazilian origin. In the coming months, scientists will have to analyze the material collected during the expedition in the laboratories and draw final conclusions.
Brazilian colleagues from the universities of Rio Grande do Sul and the State of Para also took part in the research. The authors note that the expedition allowed to obtain rare scientific data about this area of the ocean, and also became a significant milestone in the development of international scientific cooperation between the BRICS countries.
The research was carried out with the financial support of the Ministry of Education and Science of Russia and the Russian Foundation for Basic Research.
Source: BRICS website