MMBI RAS summarizes the results of comprehensive marine research in the Barents and Kara Seas, conducted aboard the R/V "Dalniye Zelentsy" from July 9 to August 8, 2025. Over 31 days of work, scientists conducted large-scale research at 45 complex stations, collecting a unique array of data on the state of Arctic sea ecosystems.
The expedition covered a wide range of scientific fields. To study thermohaline characteristics, 44 water column profiles were performed using CTD probes. Hydrochemical research was another important component: scientists collected 84 seawater samples for comprehensive analysis. These samples allow for the determination of dissolved oxygen concentration, the content of nutrients (nitrates, nitrites, phosphates, silicon), pH, and the isotopic composition of oxygen.
To study zoobenthos, samples of benthic organisms were collected using a Van Veen grab. Additionally, an analysis of bycatches of megabenthos from bottom trawlings was conducted, providing insight into large benthic communities. Bottom trawlings also provide data for studying ichthyofauna – assessing species composition and abundance, biomass, and biological condition of fish. Age samples (otoliths) were delivered for laboratory processing at MMBI. The presence of key species of Arctic fauna, such as polychaetes, ophiuroids, bivalves, and sea urchins, was recorded during the work. Additionally, sediment samples were collected for analysis of granulometric composition, organic matter content, and photosynthetic pigments.
The data collected during the expeditionary research are of fundamental importance. They will allow for an assessment of the current background state of the Barents and Kara Sea ecosystems, and an analysis of long-term trends in the variability of both abiotic (physicochemical) and biotic (biological) indicators under observed climate change and anthropogenic impact. This work is necessary for building reliable forecasts of future ecosystem processes in the Russian Arctic and monitoring possible anthropogenic impact on the marine environment. The goals and objectives of the expeditionary research were fully accomplished under supervision of the Expedition Leader Olga Zimina. All collected samples have been transferred to MMBI laboratories for further detailed research and storage.
Photo: Elizaveta Kuimova, Konstantin Muradov
