Current Hydrochemical State of the Kola Bay Waters in the Murmansk Coastal Zone

Abstract

The purpose is to determine the hydrochemical state of the surface water layer of the Kola Bay in the coastal zone of Murmansk. Materials and methods. Sampling was conducted from the surface layer of the bay waters seasonally throughout the year at the fi ve sites selected for the study. Concentrations of O2 , Zn, Cd, Pb, Cu, Hg, petroleum products, ammonium nitrogen, nitrate, nitrite, sulphate, sulphide, chloride were determined using Hanna HI 9142 oximeter, AH-2 infrared analyser, Ta-Lab inversion voltammetric analyser and Kapel-105 M capillary electrophoresis system. Results and discussion. Cadmium, lead, copper, mercury, oil products, nitrogen compounds, sulfur compounds (sulfi des) and chlorides, are found to exceed the maximum permissible concentrations (for fi shery water bodies) in a number of areas. Also, oxygen content below the normative allowable value is registered. No zinc and sulfate maximum permissible concentrations are exceeded. For a number of chemical substances (Zn, Pb, Hg, nitrites, sulfates, sulfi des) in all sampling areas seasonal dynamics of concentrations fl uctuations are observed, indicating the activation of melt water fl ows in the spring period, especially for mercury. Conclusion. According to the results of sample analysis, in a number of areas exceedances of maximum permissible concentrationsРХ of Cd, Pb, Cu, Hg, oil products, nitrogen compounds, sulphides and chlorides, as well as oxygen content below the normatively permissible value were detected. The most polluted area is ‘Green Cape (Northern berths of the seaport)’, where oxygen defi ciency and exceedances of maximum permissible concentrationРХ of for the majority of pollutants are observed throughout the year. In all cases the main factor determining the intensity of pollution in the studied period of time is economic activity.