Study of physical and chemical properties of edaphotopes of the waste dumps at coal mines in the Novovolynsk mining area

Abstract

Purpose. To define the influence of physical and chemical properties of edaphotopes that are formed at mine dumps within the Novovolynsk mining area (Ukraine) on the biogenic component of the region’s ecological safety. Methodology. The genetic horizons and the soils classification have been described according to the provisions of “Atlas of Soils”. Physico-chemical research on edaphotopes and soils within the horizons were conducted by the methods of N.B. Myakina and E.V.Arinushkina. The granulometric soil composition was determined by N.A.Kachinskii Method, with preparation by the pyrophosphate method; humus – by the Tyurin Method in the modification of Nikitin; pH of water and salt extracts – by the potentiometry method; hydrolytic acidity and the sum of imbibed bases – according to Kappen Method; degree of saturation with bases – by the calculation method; exchangeable calcium and magnesium – by the method of complexometry; easily hydrolyzable nitrogen – according to the Kornfield Method; mobile potassium – by the methods of Chirikov (non-carbonate samples) and Protasova (carbonate samples); mobile phosphorus – by the methods of Chirikov (non-carbonate samples) and Machigin (carbonate samples); СО2 of carbonates – by means of a calcimeter according to Geisler-Maksimyuk Method. The software included a package of application programs Surfer, MS Excel, MS Visio, Paint. The rock temperature was set using an HP-1300 pyrometer. Rock moisture was measured using a MG-44 moisture meter. The level of radiation background was measured with the use of “Soeks” environmental tester. Findings. During field studies in the Novovolynsk mining area, it was found that coal mine dumps are represented by three types of edaphotopes – rock (black) refuse, burnt (gray) rock and bulk soil mixtures. It has been established that the black burnt rock of the waste heap (light loamy soils) contains a significant amount of nitrogen, while the clay mass and middle loamy burnt rock has a very high content of easily hydrolyzable nitrogen (46.2 mg/100 g of rock). The study of burnt gray rock near the ignition sources at No. 9 Novovolynska mine showed that it is characterized by a high content of organic acids of unknown origin. The humus content in reclaimed soils is 0.45–4.52 %, and according to the humus gradation, they can be assigned to the group of soils with low humus content. The high acidity of the soil mixtures on the reclaimed waste heap at No. 2 Novovolynska mine suppresses the development of tree-shrubbery vegetation and slows its growth. Originality. It has been found that edaphotopes of waste dumps at coal mines of the Novovolynsk mining area are characterized by a low level of supply with organic substances, but high acidity. The patterns of changes in the temperature and humidity conditions of the waste dump have been determined, where the combustion processes are still observed. It has been proved that burning of dumps determines the change in the physical-chemical properties of the rock refuse and has a direct influence on the development of tree-shrubbery vegetation. Practical value. The established physical and chemical properties of edaphotopes, which are formed under the influence of temperature and humidity conditions at mine dumps within the Novovolynsk mining area, are recommended to be taken into account for substantiation of the choice of tree and shrub vegetation types when conducting the works on phytomelioration. The obtained data on temperature conditions should be taken into account when developing the plans to prevent spontaneous ignition and extinguishing of waste dumps, as well as in case of their further reclamation.