SOIL DEGRADATION AND MODIFICATION OF OTHER NATURAL FACTORS AS A RESULT OF OPEN CUT COAL EXTRACTION IN OLTENIA MINING BASIN, ROMANIA.

The Oltenia Mining Basin extends, intermittently from west to east, from the Danube to the Luncavat Stream, Valcea County. It is located as a fan shape at the contact area between the Getic Plateau and the Mehedinti Plateau, to the west of the Motru River and the Subcarpathian Depression of Oltenia, to the east of the Motru River, with the mention that most mining objectives are to the south of the contact area or in the immediate vicinity nearby.The surface mining operations in the Oltenia basin have affected large areas of land, causing radical changes to the soil.Subsoil, geomorphology and landscape, coal deposits, waters, climate, vegetation, human communities, economic and social development have undergone substantial changes.All of this generates significant changes in the natural aspect of the area, resulting in anthropic relief inversion areas.Under the influence of the pedogenic factors acting in the Oltenia mining area, the following units were formed as initial soils: preluvosoil, luvosoil, albic luvosoil, eutricambosoil, vertosoil, regosoil, stagnosoil and aluvisoil.Through open cut mining, the impact on the soil was very tough, through the process of removing or overburden dumping, the soil disappeared either by inseparable mixing with the overburden or by being deposited separately.Instead of the disappeared initial soils, at present there are lithological materials very different from a physical and chemical point of view, of different ages that are heterogenously mixed and forming the technosolis. Technosoils were formed by depositing lithological materials in heaps over 50 cm without prior selection of excavated materials. From this point of view, we cannot talk about well-defined horizons, but only about sections of different thicknesses. The sections, irrespective of their number, show different colors and their unstructuredness is obvious. Each section of the technosol has different texture; the humus content is different on the depth of the section, in smaller percentages on the surface and the higher in depth. Most times, technosols provide enough edafic volume for the development of the root system of crop plants; instead they are devoid of life without the essential characteristic specific to an evolved soil, namely fertility. All these aspects explain the disturbance, the destruction of soils through open cut mining operations. It can be concluded that a natural organism, a living body, formed in time, with all its properties, primarily fertility, which provides a favorable environment for plant development dissapeared [ABSTRACT FROM AUTHOR]