The First Detection of Hypoxia in Vostok Bay (the Sea of Japan)

A hypoxic zone with dissolved oxygen concentrations of 3.0–3.6 mL/L (42–51% saturation) was first discovered in the bottom depression in the Srednyaya Cove (between the Pushchin and Pashinnikov capes) in Vostok Bay in July–September 2021. It existed from mid-July to mid-September. It was revealed that the surveyed area was characterized by high concentrations of phosphates at bottom horizons and organic carbon in sediments. It was shown that the formation of the hypoxic zone occurred as the result of an increase in the anthropogenic impact on this sea area.