ENERGY AND THERMODYNAMIC CHARACTERISTICS OF PARENT MATERIAL AND RENDZINAS (RENDZIC LEPTOSOLS) OF THE PODILSKI TOVTRY

Abstract

AbstractProblem Statement and Purpose. In recent years, the practice of applying energy and thermodynamic characteristics of parent material and soils to the establishment of the potential of soil formation has become more widespread. The development of this area of research creates certain possibilities for using the thermodynamic characteristics of soils and parent material: the energy of the crystalline lattice, Gibbs free energy and the entropy of the mineral part to assess the ability of rocks to soil formation. Therefore, it is extr emely promising and topical to study the processes of soil formation from the energy and thermodynamic point of view. The purpose of the study is to establish the energy and thermodynamic characteristics of parent material and rendzinas (Rendzic Leptosols) of the Podilski Tovtry.Data & Methods. During 2013-2017 we laid down 5 modal sections. The system of soil sections represents rendzinas in different lands: arable lands, fallows and virgin areas under forest and meadow phytocenoses.To install Energy and thermodynamic characteristics of parent material and rendzinas (Rendzic Leptosols) of the Podilski Tovtry we have applied methods based on data conversion of the gross chemical composition, humus content, bulk density of the studied soils and parent material in the energy indices: the energy of the crystalline lattice (Um), Gibbs free energy (Gm298 15) and the entropy (Sm298 15) and the humus energy.Results. A characteristic feature of the rendzinas and parent material is the high energy reserves of the crystalline lattice (U111 = 6951.44-17728.82 kJ/g) and Gibbs free energy (Gm29815 = 1089.07-1327.72 kJ/g) and slightly changing values of entropy (Sm29815 = 65.12-67.75 kJ/gxdegrees), which is due to significant CaO content. The investigated parent material are characterized by a high content of nonsilicon energy, since they are enriched predominantly on CaC03, in contrast to rocks that have high crystalline lattice energies due to the high content of silicon. This crystalline lattice is strong and harder to break down. This creates conditions for the accumulation of residual minerals in the soil. This implies indirectly about residual claying of soil profile. The upper genetic horizons of the rendzinas profile are characterized by the highest values of the energy of the crystalline lattice (Um). The values are within the range 16569.21-17778.82 kJ/g and decrease down the profile to 7932.12-13318.39 kJ/g. This is due largely relative content of Si02. which has the highest energy figures and, accordingly, most influences on their reserves in the soil. For The studied rendzinas a significant variability of humus energy is characteristic. Typical rendzinas, formed on dense limestones of the tops of the Podilski Tovtry, are characterized by the largest reserves of energy in humus (2347-2488 mJ/ha in 10 centimeters of humus horizon Hca). Brown pararendzynas. formed on the slopes of the Tovtry. characterized by minimal humus energy (742.13 mJ ha).