Ecological and geological determination of the initial pedogenesis on devastated lands in the Kryvyi Rih Iron Mining & Metallurgical District (Ukraine)

Abstract

In our time, a very urgent problem is the cessation of negative impacts on the environment and the return to the practical use of the territories of devastated lands. In  this regard, it is important to find out the basic laws of primary soil formation in the area of these man-made neoplasms. The initial soil formation conditions were analyzed on 19 experimental sites which represent the main varieties of devastated land in the Kryvyi Rih Iron Mining and Metallurgical District (Central Ukraine): (i) waste rock dumps of old iron mines (old name “Forges”), (ii) tailing storage facility of underground iron mines, (iii) waste rock dumps of the Iron Ore Mining and Dressing Plant, (iv) waste rock dumps of the Granite Quarry Plant. It was established that on the devastated lands in Kryvyi Rih District, the initial soil formation occurs in very difficult conditions. Therefore, over 25- 100 years only very primitive soils were formed. The following features are inherent to them: (1) primitive soil profile (thickness 10-100 mm), (2) low levels of soil organic substance content (9.5-11.5 %), (3) alkaline indicators of the soil solution (pHH2O – 8.08-8.92, pHKCl  – 7.42-8.23), (4) low levels of cation exchange capacity (6.34-8.47 mMol /100 g). By results of correlation calculations, among the factors of soil formation time (duration of soil formation) and input of plant ash elements’ fall are characterized by the maximum number of statistically significant correlation coefficients and their numerical values. In terms of chemical composition of the technosol, the values of organic matter content and exchangeable acidity (pHKCl) were the most predictable soil formation factors. Generally physical / chemical characteristics of geological rocks (as parent material) and time were the two most important factors in determining the initial pedogenesis on devastated lands in the Kryvyi Rih Iron Mining & Metallurgical District (Ukraine).