Geoecological aspects of chemical element migration in soils of the waste heap impact zone at the Bogdanka Mine, Lublin Coal Basin

Purpose. This research aims to explore the peculiarities of chemical soil pollution and analyse the patterns of chemical element migration in the waste heap impact zone of the Bogdanka Mine in the Lublin Coal Basin compared to the control area. To achieve the purpose set, soil samples were taken from various ecotopes at depths of 0-5, 5-10, and 10-15 cm, the ecological state of the territories was assessed, and a statistical analysis of the chemical element content was performed. Methods. The research was based on methods of statistical data processing, correlation and cluster analysis, multidimensional ecotope ordination using Principal Component Analysis (PCA) and canonical discriminant analysis. Sampling was conducted in accordance with the ISO 10381-8:2006 standard. Analytical determinations of elemental composition were performed using X-ray fluorescence spectrometry on an ElvaX Light SDD device. Findings. Significant spatial heterogeneity in the distribution of macro- and microelements in soils of the waste heap impact zone has been identified. Increased concentrations of Mg, Al, S, K, Ti, V, Fe, Ni, Cu, Zn, Sr, Y, and Pb were recorded at the foot of the waste heap. The maximum values of individual elements are typical for specific ecotopes, in particular Mn and Zr for coastal and forest areas. The highest exceedance of maximum permissible concentrations was found for Cu, Ni, and Zn (up to 22.3, 20.1, and 30 times, respectively). Originality. The scientific novelty of the research consists in determining the spatial gradients of chemical soil pollution in the impact zone of coalmine waste heap based on multidimensional ordination of ecotopes. 2D graphic visualization of geo-chemical indicators, the axes of which are chemical element concentrations or integral gradients of the environment, provides a clear representation of the migration processes of elements in soils of various ecotopes. Practical implications. The practical significance of the results obtained lies in the possibility of using the identified patterns of chemical element distribution to assess the level of soil pollution in the impact zone of the waste rock dump. The data obtained can be used to predict local changes in soil cover quality and to substantiate measures to reduce the negative impact of heavy metals on the soil environment of adjacent territories.