Известия Томского политехнического университета: Инжиниринг георесурсов (Mar 2021)
MATERIAL COMPOSITION OF PEATS OF THE TIMIRYAZEVO MIRE (TOMSK, WESTERN SIBERIA)
Abstract
Relevance. Mires are simultaneously the indicator of the condition of an environment, including the river and ground waters connected to mires. It is especial in the area of accommodation of a large drinking water supply system, for example, the Tomsk system of drinking water supply from groundwaters. The aim of the research is to reveal the changes of the chemical composition (acid peat extracts) and mineral inclusions as indicators of mire formation conditions according to nature and anthropogenous influence in the peat deposit of the Timiryazevo mire (the western corner of Tomsk city, Western Siberia). Methods: methods of definition of chemical and mineral composition of peat and soils, statistical methods. Results and conclusions. An uneven change of ash content, Al, Ti, Cr and other elements was revealed with a maximum in the upper and lower layers of the peat deposit in proportion to mineral sources (atmospheric dust and underlying clays, respectively) for mesotrophic Timiryazevo mire in the Tom river valley near the Tomsk city. An assumption is made about the presence of a general mechanism for peat formation and the transformation of mineral inclusions in mires based on the environment filtration properties taking into account the previously obtained data for the Vasyugan mire. The main features are the biochemical transformation of mineral substances coming from the atmosphere, or surface and ground flow from drylands. As a result, the substance is in a dissolved, colloidal and suspended form in the active horizon. Mineral phases are formed in the inert horizon. Trace elements co-precipitate on the surface of these particles (also particles of hydroxides) and authigenic minerals including phosphates of rare earth elements are formed. The velocity and direction of these processes depend on the geomorphological and hydrological conditions that determine the emergence and functioning of geochemical barriers.
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