Alteration Of Physico-chemical And Morphological Characteristics Of Sod-podzolic Soils In Technogenically-affected Landscapes Of Moscow Brown Coal Basin
Kostin, Alexander; Krechetov, Pavel
Lomonosov Moscow State University, Russian Federation
Long-term coal mining in the Moscow basin has led to changes in soil properties of natural landscapes. Toxic spoil heaps of sulphide-bearing overburden rocks and subsidences over the mined space are formed at abandoned mine fields. Acid mine drainage (AMD) of sulfuric acid, Al and Fe sulfates with pH values close to 3,0 as well as pyritized technogenic material, entering from eroded spoil heaps, result in morphological changes in soil properties. This study aimed at evaluation of physico-chemical transformation of soil properties, which is adjacent to spoil heaps. Studies were conducted at Cherepet brown coal deposit in the Tula region (Russia). Natural soils are Albeluvisols (WRB 2014) (Sod-podzolic soils in Russian classification). On deluvial foreslopes around spoil heap technogenically transformed soils are common. Forms of soil acidity (total titratable acidity, exchangeable acidity, hydrolitic acidity), content and composition of readily soluble salts, content of Fe compounds, composition of exchangeable cations, content of organic carbon and some other chemical properties were determined in technogenic sulphide-bearing materials, AMD, soil samples and soil solutions. Technogenic transformed soils are characterized by acidic reaction with a high content of Fe and Al sulfates as well as a considerable amount of exchange, hydrolytic and total titratable acidity, in soil solid phases and soil solutions, respectively. It is revealed that technogenically transformed sod-podzolic ferrugenous soils, in relation to natural soils, has a specific morphologic features: intensificaton of eluvial process (silt loss and bleaching of soil mass) along with intensive accumulation of iron (nodules and patches of Fe oxides and hydroxides) and organic matter of coal origin. Sod-podzolic-gley soils with transformed water regime are formed in mine subsidences.