CERIUM IN THE LANDSCAPE COMPONENTS OF THE SHERLOVOGORSKIY MINING REGION (SOUTHEASTERN TRANSBAIKALIA)

Abstract

The relevance of the study is in the need to know the biogeochemistry of lanthanides in natural-anthropogenic landscape. The aim of the work is to study the behavior of the cerium geosystem of the unique rare-metal-tin-polymetallic Sherlovogorsk mining region in the South-Eastern Transbaikalia. The research methodology is to study the behavior of cerium in the links of the chain: rock (ore)→(technosoil)→plant→root system→ground part. Sampling of soil-forming rocks, ores, soils and plants was carried out during the field seasons 2001–2016. Soil samples were selected in accordance with GOST 17.4.4. 02-84, by artificial outcrops. In this work, data from analysis of 37 samples of rocks and ores, 211 soils, 119 technozems and 215 samples (3225 specimens) of grassy plants were used. The method of the work consisted in mineralogical and geochemical study of rocks and ores using optical and electron microscopy. The chemical composition of rocks, minerals, soils, technozems and plants was studied by ICP MS. Results. The authors have studied cerium behavior in the landscape of the Sherlovogrsk ore field. The main source of cerium in the soils and technozams of the ore region is monazite-(Ce). It is located in greisens and quartz-vein bodies, localized in the Sherlovogorsk granite massif, oxidized ores stored in substandard depots and dumps. Other carriers of cerium are agardite and godeite. It is also included in the composition of fluorite (8,2–1182 ppm), wolframite (0,4–11,1 ppm), clay residual cavities in the veins, which are productive for gemstone raw materials (3,3–206 ppm). The content of cerium in beryl (0,1–1,2 ppm) and topaz (0,2–2,81 ppm) are insignificant. The content of Ce in the sulfide mineral complex in the veins with gemstone raw material varies from 5,6 to 99,4 ppm. In the finely clastic material of soils and technosoils, the Ce content is in the range of 51–384 ppm. The experiments showed the possibility of transporting cerium onto the landscape with aqueous solutions containing up to 0,73 ppm. In all areas, the average content in soils is within 3,3–310 ppm, and in technosoils – 30–377 ppm. The maximum content of cerium (ppm) is set in the roots of grassy plants (1,0–3,9) (CBА 0,02–0,03), and the minimum in their terrestrial parts (0,8–1,4) (KBА 0,01–0,02). This indicates a very slight seizure of its plants and a low content of grazing plants in the forage. However, how safe it is for pets has not been yet known and requires special research.

Keywords

• cerium
• landscape
• soil
• tecnosoil
• plant
• biological absorption coefficient
• accumulation
• plant organs
• sherlovogorskiy mining region
• transbaikalia