35
radionuclides in the environment and an increase in the content of radionuclides in
those components that determine the intake of radionuclides in the human body.
One of the ways of radionuclide penetration into the human body is through
trophic chains, in which the “soil plant” plays an important role. Information on the
forms of radionuclides in the soil that determine the radionuclide intake to plants is
undoubtedly of interest. The study of the behavior of natural and technogenic radionuclides entering into the ecosystems from anthropogenic sources makes it possible
to control the radioactivity of the environment and to reveal the nature of the effect
on the ecosystems of natural and introduced radioactivity.
Countries that develop nuclear energy, including Belarus, should have a reliable
system of radiation monitoring. Current monitoring systems in economically developed countries allow monitoring radioecological situations. However, even the most
advanced of them are not able to fully ensure the prediction of the radioecological
state of the territories without assessing the parameters characterizing the mobility
of radionuclides in ecosystems. When assessing and forecasting the radioecological
situations, an assessment of the reliability of geochemical barriers that prevent the
spread of radionuclides beyond the limits of their localization should be considered
among the primary scientific and applied problems. In terrestrial ecosystems, the
main barrier function is carried out by the soil cover, which has a determining effect
on the intake of radionuclides into groundwater and surface water, vegetation and
other ecosystem components, and ultimately to the human body. The properties of
soil as a natural geochemical barrier that prevents the migration of radionuclides in
terrestrial ecosystems are determined by its sorption characteristics and can be estimated from the distribution of radionuclides between the solid phase and the pore
moisture of the soil. Such information helps to identify places with increased mobility of radionuclides and to assess the environmental consequences of the presence
of radionuclides in the environment (Sokolik et al. 2012).
The redistribution of radionuclides in terrestrial ecosystems essentially depends
on that part of the radionuclides that is reversibly bound in the soil with the components of the sorption complex. These are, as a rule, radionuclides located in the soil
in ionic or molecular form and capable of passing from the solid phase to the pore
waters of the soil and genetically related with them surface and ground waters.
Radionuclides of soil pore solutions, most actively included in the processes of
biogeochemical migration, can be identified as radionuclides in a migratory-active
form. Radionuclides reversibly associated with the solid phase of the soil (exchangeable forms) compensate for the loss of radionuclides in the pore solution when
interfacial equilibrium is disturbed (intake of radionuclides into groundwater and
vegetation assimilation), seeking to restore the disturbed equilibrium. In terrestrial
ecosystems, the migratory-active, exchangeable and mobile (biologically accessible) radionuclide species are among the main indicators determining the migration
properties of radionuclides in the soil-vegetation cover.
The state and mobility of uranium in the soil-vegetation cover depends significantly on the characteristics of the soil. Long-term changes in meteorological
conditions affect the properties of the soil (The Second Congress of the Soil Science
Society 1996; Loginov et al. 2010). The most significant meteorological parameters
Uranium and Its Distribution in Typical Belarusian Soils
radionuclides in the environment and an increase in the content of radionuclides in
those components that determine the intake of radionuclides in the human body.
One of the ways of radionuclide penetration into the human body is through
trophic chains, in which the “soil plant” plays an important role. Information on the
forms of radionuclides in the soil that determine the radionuclide intake to plants is
undoubtedly of interest. The study of the behavior of natural and technogenic radionuclides entering into the ecosystems from anthropogenic sources makes it possible
to control the radioactivity of the environment and to reveal the nature of the effect
on the ecosystems of natural and introduced radioactivity.
Countries that develop nuclear energy, including Belarus, should have a reliable
system of radiation monitoring. Current monitoring systems in economically developed countries allow monitoring radioecological situations. However, even the most
advanced of them are not able to fully ensure the prediction of the radioecological
state of the territories without assessing the parameters characterizing the mobility
of radionuclides in ecosystems. When assessing and forecasting the radioecological
situations, an assessment of the reliability of geochemical barriers that prevent the
spread of radionuclides beyond the limits of their localization should be considered
among the primary scientific and applied problems. In terrestrial ecosystems, the
main barrier function is carried out by the soil cover, which has a determining effect
on the intake of radionuclides into groundwater and surface water, vegetation and
other ecosystem components, and ultimately to the human body. The properties of
soil as a natural geochemical barrier that prevents the migration of radionuclides in
terrestrial ecosystems are determined by its sorption characteristics and can be estimated from the distribution of radionuclides between the solid phase and the pore
moisture of the soil. Such information helps to identify places with increased mobility of radionuclides and to assess the environmental consequences of the presence
of radionuclides in the environment (Sokolik et al. 2012).
The redistribution of radionuclides in terrestrial ecosystems essentially depends
on that part of the radionuclides that is reversibly bound in the soil with the components of the sorption complex. These are, as a rule, radionuclides located in the soil
in ionic or molecular form and capable of passing from the solid phase to the pore
waters of the soil and genetically related with them surface and ground waters.
Radionuclides of soil pore solutions, most actively included in the processes of
biogeochemical migration, can be identified as radionuclides in a migratory-active
form. Radionuclides reversibly associated with the solid phase of the soil (exchangeable forms) compensate for the loss of radionuclides in the pore solution when
interfacial equilibrium is disturbed (intake of radionuclides into groundwater and
vegetation assimilation), seeking to restore the disturbed equilibrium. In terrestrial
ecosystems, the migratory-active, exchangeable and mobile (biologically accessible) radionuclide species are among the main indicators determining the migration
properties of radionuclides in the soil-vegetation cover.
The state and mobility of uranium in the soil-vegetation cover depends significantly on the characteristics of the soil. Long-term changes in meteorological
conditions affect the properties of the soil (The Second Congress of the Soil Science
Society 1996; Loginov et al. 2010). The most significant meteorological parameters
Uranium and Its Distribution in Typical Belarusian Soils