Behaviour and distribution of heavy metals at the boundary of “water-bottom sediments” in mouth zones of rivers

The aquatic elementary landscapes of the Don and Northern Dvina Rivers mouth zones as arenas mass transfer heavy metals (HM) are studied. results long-term comprehensive studies authors, which included sampling water upper layer bottom sediments in order to determine content mercury, copper, methane, hydrogen sulfide, well pH Eh values, presented. According type prevailing geochemical conditions level anthropogenic impact, natural, man-made natural-anthropogenic distinguished. layers both rivers were characterized by positive but it should be noted that they generally relatively low for surface watercourses. values redox potential index, methane total presence following is proved – oxygen, gley, oxygen-gley gley-hydrogen sulfide. At - sediment interface, most cases, there was a decrease first tenths while usually decreased quite sharply, often negative values. In terms content, similar, concentration sulfide higher Don. It shown zone rivers, areas subject constant organic pollution eutrophication, an increase mercury copper sediments. Higher concentrations gross will found natural dominated environments. important role microparticles polydisperse medium deposition revealed.