Regional features of heavy metals distribution in bottom sediments and surface water within river basins in Ukraine

Abstract

Summary GIS analysis of large amount spatial information on the chemical composition of bottom sediments and surface waters made it possible to determine the background content of lead, zinc and copper, as well as to establish patterns of their distribution within Ukraine river basins and sub-basins. Available data made it possible to determine the approximate coefficients of water migration of the metals. It was found that the variation range of the background metal content in bottom sediments in different river basins is 3.75–6.67 times. At the same time, for surface waters, this indicator is much higher - 38.5–88 times. The chemical composition of bottom sediments reflects the chemical composition of soils in catchment areas. Оn the contrary, the surface water chemical composition depends on a lot of factors. Analysis of the content of metals in water and bottom sediments of lowland rivers showed the presence of a relationship between them, while for mountain rivers there is no correlation, which is associated with the priority of hydrodynamic factors (rapid water exchange) in the formation of the water qualitative composition of the latters. The results obtained can be used for regional assessments of water bodies’ quality status and for information support for natural waters monitoring.