The Carbonate System of the Estuaries of the Syran and Ul'ban Rivers (Ul'banskii Bay, the Sea of Okhotsk) during Spring Flood.

In the period of summer flood 2016, a number of chemical characteristics associated with carbon cycle were studied in the estuaries of the Syran and Ul'ban rivers in the area of the Shantarskii Archipelago with the total water discharge of 194.7 m³/s. The zone of mixing at the salinity of <20‰ is the source of CO₂ for the atmosphere with the estimated CO₂ flux up to 112.7 mmol m⁻² day⁻¹. At the salinity >20‰, the thickness of the photic layer increases abruptly and photosynthesis starts to dominate, resulting in the formation of CO₂ flow from the atmosphere into water with a rate of up to 30 mmol m⁻² day⁻¹. A model CO₂ flow at the water/atmosphere interface is presented at a wind speed from 2 to 15 m/s for the entire mixing zone, the water in which generally absorb atmospheric CO₂. A specific feature of the basin compared with the estuaries of the Uda and Usalgin rivers in the zone of the Shantarskii Archipelago is the combination of the relatively low volume of water and solid runoff with a relatively high phosphorus flux in mineral and organic forms. [ABSTRACT FROM AUTHOR]