Spatio-Temporal Dynamics of Soil Geochemical Anomalies in the Zone of Impact of Slag Residuals

Abstract

The 13-year-old (from 2003 to 2016) dynamics of soil contamination for the content of heavy metals in the area of the village of Bolshoye Dumchino of the Mtsensk District in the territory adjacent to the slag dump of Mtsensk Foundry was studied. It is shown that on the territory of the placement of slag residuals a techno geochemical anomaly is formed, in which the contained heavy metals are of technogenic and genetic (natural geochemical) nature. To identify the effect of anthropogenic factor on soil pollution with heavy metals, was determined the refined enrichment factor of heavy metals (EFHM) in light gray forest soils at different distances from the slag dump, allowing to calculate the proportion of technogeneity of metals as a percentage of its total content. The technogenic origin of heavy metals as pollutants and the role of humus soil horizons in fixing these metals in the soil profile have been proven. Analysis of the results characterizing the degree of enrichment of the genetic horizons of light gray forest soils with heavy metals for the period 2003–2016 convincingly proves the effect of maximum accumulation of slag residuals in the dump on the accumulation intensity and fixation of the studied metals, both in the upper humus layer and their distribution in the profile soil. The established patterns in changing the degree of enrichment and technogenicity of heavy metals in the profile of light-gray forest soil are caused not only by the impact of the slag dump as a source of pollution, but also by the peculiarities of using the soils of the studied territories. It is shown that the toxic load for the analyzed period not only did not decrease, but even increased.