AGROECOLOGICAL CONTROL OF IRON AND MANGANESE CONTENT IN BOTTOM SEDIMENTS OF AGRICULTURALLY SIGNIFICANT RESERVOIRS IN KAZAKHSTAN

Abstract

The article presents the results of research on bottom sediments in the coastal zones of the Verkhnietobolskoe and Karatomar reservoirs of the Republic of Kazakhstan. Sampling was conducted during the winter period under low-temperature conditions from beneath the ice cover of the water bodies. The research results reflect the content of heavy elements, such as iron and manganese, in the bottom sediments. It was found that the average content of these elements, recalculated from their oxide form to the elemental form, does not exceed the average Clarke values of elements in the Earth’s crust. The obtained results are consistent with the provisions of the UNECE Guidelines on Monitoring and Assessment of Transboundary and International Lakes, which emphasize that coarse-grained components of bottom sediments are typically characterized by low levels of heavy metal content. The results of this study can be used as reference information on the qualitative composition of bottom sediments in flowing water bodies of temperate climate regions; as methodological recommendations for organizing and conducting comprehensive assessments of qualitative and toxic indicators of bottom sediments in freshwater flowing water bodies; as methodological guidance for implementing rapid X-ray fluorescence spectral analysis of solid-phase forms of bottom sediments; and for monitoring heavy metal content in water bodies intended for agricultural use.