Heavy Metals and Organic Carbon in the Bottom Sediments of Shallow Bights of the Peter the Great Bay

A noticeable feature of labile heavy metals is that they are highly prone to be to bioaccumulated and bioassimilated in natural environments. When in high concentrations, these metals are toxic to living organisms, as is particularly evident in the coastal shallow marine zones, which are most strongly affected by anthropogenic processes. This paper presents data on the contents of heavy metals, concentrations of organic carbon, and the granulometric composition of bottom-sediment cores in three shallow bights of the Peter the Great Bay, in two of which (Voevoda and Novgorodskaya bights), large bottom areas are overgrown with seagrass Zostera marina L. (sea zostera, ZM). Data on the vertical distribution of heavy metals and organic carbon in the cores showed that the highest concentrations of Zn and Cu (up to 204 and 91 mg/kg, respectively) occur in samples from Voevoda bight, and the highest concentrations of Mn and Pb (up to 344  and 45 mg/kg, respectively) were found in Novgorodskaya bight, where meadows of the seagrass grow. The highest Cr, Ni, and Co contents (up to 69, 31, and 13 mg/kg, respectively) were identified in Uglovoy bight, where sea grass is practically absent.