Abstract
The article presents the results of comprehensive studies of the hydrological and chemical structure of the Middle and Northern Caspian Sea carried out aboard R/V Issledovatel Kaspiya in September 2022. It is shown, despite the continuing decrease in sea level, that there is no aeration of deep layers and a hydrogen sulfide layer persists with a tendency towards an increasing hydrogen sulfide concentration in the bottom layer. There is an enlargement in the oxygen minimum zone. The changes of the Caspian Sea ecosystem have led to weakening of nutrient transfer from the photic layer into the bottom layers and, as a consequence, to a decrease in the silicon concentration in the bottom layer. The results will make it possible to evaluate trends of ongoing changes.
This is a preview of subscription content, log in via an institution to check access.
REFERENCES
L. A. Dukhova, E. A. Serebrennikova, A. K. Ambrosimov, et al., “Hydrochemical studies of deep-water basins of the Caspian Sea in August–September 2013 aboard the R/V Nikifor Shurekov,” Oceanology 55 (1), 145–147 (2015).
Guidelines for the Chemical Analysis of Sea and Fresh Waters during Environmental Monitoring of Fishery Reservoirs and Promising Fishing Areas of the World Ocean, Ed. by V. V. Sapozhnikov (Izd. VNIRO, Moscow, 2003) [in Russian].
N. I. Torgunova, N. V. Arzhanova, A. S. Khursanov, et al., “Hydrological and hydrochemical studies in the Middle Caspian Sea in July–August 2019,” Tr. VNIRO 180, 174–178 (2020).
ACKNOWLEDGMENTS
The authors thank the scientific group of the Volga-Caspian Branch, Russian Research Institute of Fisheries and Oceanography, and the crew of the R/V Issledovatel Kaspiya for their assistance in the research.
Funding
This work was supported by ongoing institutional funding. No additional grants to carry out or direct thisparticular research were obtained.
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
CONFLICT OF INTEREST
The authors of this work declare that they have no conflicts of interest.
ETHICS APPROVAL AND CONSENT TO PARTICIPATE
This work does not contain any studies involving human and animal subjects.
Additional information
Publisher’s Note.
Pleiades Publishing remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
About this article
Cite this article
Dukhova, L.A., Suvorova, A.S., Gruzevich, A.K. et al. Hydrogen Sulfide Contamination Studies in the Deep-Water Basin of the Middle Caspian Sea during a Cruise of the R/V Issledovatel Kaspiya in September 2022. Oceanology 64, 329–331 (2024). https://doi.org/10.1134/S000143702402005X
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S000143702402005X