Geochemical barriers of manganese distribution in edaphotopes of Dnieper Prysamarye

The article is devoted to the study of vanadium, a metal capable of stimulating the growth of phytoplankton in situ and has the greatest biological activity in dissolved form. The pattern of an increase in the concentration of vanadium dissolved forms in the mixing zones during the transition from river waters to seawaters is known. In this article, we examine the behavior, ratio and change in the concentrations of vanadium dissolved and suspended forms during the passage of geochemical barriers. The estuarine zone of the Razdolnaya River–Amur Bay (Sea of Japan) is considered as "river-sea" mixing zone. Modelling of physicochemical processes was carried out using the Selector-S and MINTEQA2/PRODEFA2 software systems. Ion-associative models of sea and river water were built and the modelling of the process of their mixing was carried out using the Selector-S software package. The sorption process was simulated using the MINTEQA2/PRODEFA2 software package. The results of modelling physicochemical processes occurring at geochemical barriers help to understand the reasons for changes in concentrations, both total vanadium and biologically active dissolved vanadium forms, during the passage of geochemical barriers in the "river-sea" mixing zones. The results showed that there is a change in the dissolved forms of vanadium migration, their transformation and an increase in the concentration of dissolved forms of vanadium at the geochemical barrier

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RESTORATION OF SOILS CONTAMINATED WITH RADIONUCLIDES BY PHYTOREDOMEDIATION METHOD

10.46813/2020-126-151 ◽

2020 ◽

pp. 151-155

Author(s):

I.V. Udalov ◽

V.A. Peresadko ◽

O.V. Polevich ◽

A.V. Kononenko

Keyword(s):

Model Experiment ◽

Toxic Elements ◽

Vegetation Period ◽

Soil Restoration ◽

Soil Conditions ◽

Geochemical Barriers ◽

Artificial Geochemical Barriers

The possibility of soil restoration by means of phytotechnology and artificial geochemical barriers (GB) from contamination by radionuclides (RN) and toxic elements (TE) is methodologically substantiated. For this purpose, a number of artificial GBs were created at a special landfill within the framework of a model experiment. The process of formation and development of barriers, their parameters are investigated. Agrophytocenosis cultures were selected for optimal phytostabilization of soil conditions. The study of phytoextraction of TE and RN by agrophytocenosis cultures during one complete vegetation period was performed. Some selectivity of the investigated plants for extraction of different TEs and RNs from soils and material of barriers was revealed.

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Role of geochemical barriers in forming sulfide ores in various geological environments

Domestic geology ◽

10.47765/0869-7175-2021-10014 ◽

2021 ◽

pp. 63-73

Author(s):

IRINA GABLINA

Keyword(s):

Sulfide Ores ◽

Atlantic Region ◽

Geochemical Barriers ◽

Sulfide Ore ◽

Cupriferous Sandstone ◽

Central Atlantic ◽

Ore Types ◽

Long Term Studies

Based on long-term studies of cupriferous sandstone and shale deposits, as well as deepsea sulfide ores, various types of geochemical barriers where sulfides form are shown. Cupriferous sandstones and shales form as metals precipitate from redbed reservoir waters on H2S geochemical barrier. Syngenetic and epigenetic barrier types are identified. Oceanic sulfide ores from the Central Atlantic region were studied; as a result, a new hydrothermal-metasomatic sediment-hosted mineralization type was found, along with previously known sulfide ore types (massive ores on the seafloor and stockwork ores in substrate rocks). Geochemical seafloor sulfide formation environments and those in biogenic carbonate bottom sediments are examined.

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