Technogenic geochemical evolution of chernozems in the sulfur coal mining areas

• DOI: 10.1007/s11368-018-2010-7
• Publication Date: 2018-05-06T21:33:44Z
• Authors: Pavel Krechetov; Olga Chernitsova; Anna Sharapova; Elena Terskaya
• Keywords: Acid Mine Drainage

In sulfur coal mining areas, soils are impacted by acid mine drainage and solid-phase mine wastes containing sulfides and carbonaceous particles. Formation of new landforms leads to alteration of soil hydrological regime. The aim of the study was to examine the evolution of morphological and chemical properties of chernozems under the impact of supply of technogenic material from the spoil heaps and changes of the terrain in abandoned sulfur coal mining areas. We examined waste dumps and acid mine drainage (AMD) released from two abandoned spoil heaps in the Tula Region (Russian Federation) and soils on the adjacent territories. Sampling and description of soil morphology were performed twice for each site with an interval of 10 years. Composition and content of salts in soils and waste dumps, exchangeable cations and organic carbon in soils, mineralization of AMD, and some other chemical properties were determined. Technogenically transformed chernozems with complex morphological structure and specific chemical properties of soil profile were formed. The content of readily soluble salts exceeded 1% compared with < 0.1% in natural chernozems. Concentrations and ratio of Ca2+ and Mg2+ in soil horizons changed. The amount of extractable acidity was up to 17.5 cmolc kg−1. Concentrations of organic carbon exceeded background values by 1.2–2.6 times. Long-term supply of sulfide-containing technogenic material to the environment led to significant geochemical transformation of chernozems. Morphological and chemical properties of the post-technogenic soils in the vicinity of spoil heaps have no analogues in natural forest-steppe landscapes of the Russian Plain.