Tronza G. Influence of long-term rice-sowing on physical and chemical properties and salt regime of solonetz in the meadow zone of Dry Steppe

Object - a physical and chemical condition of meadow solonetz in virgin soils and its transformation under the influence of long-term rice planting. Purpose - to establish the influence of long long-term rice planting on the salt mode and physical and chemical properties of meadow solonetz, to define the directions of their evolution in natural conditions. Methods - field and laboratory-analytical researches; methods of variance analysis. Theoretical results - there are established features of the transformation in the ecology of meadow solonetz, structures of their profiles, water and salt modes under the influence of long-term rice planting. Specificity desalinization and desolonetzization of soils in rice and alfalfa agricoenosis is revealed. It is proved that in the development of these processes the water stagnant mode plays the basic role during the rice vegetation. Practical results - use necessity of the average models of salt profiles, profile distribution of the sum and structure of the absorbed bases meadow solonetz taking into account the share of the participation of their separate kinds in the structure of a soil cover and the transformation of the profile structure for the objective estimation of the degree of parameter changes under the influence of long-term rice planting is proved. In the part of the crop rotation "barley + Lucerne, Lucerne, Lucerne" it is necessary to apply watering because at their absence progressing processes of secondary salinization are precisely shown, and the danger of solonetz restoration amplifies. Novelty - for the first time in Ukraine on the basis of the system approach to researches there are in details studied salt profiles, and also distribution in the separate genetic horizons of physical and chemical parameters of meadow solonetz: crustal, fine, average and deep, that has allowed to reveal close genetic communication between the investigated kinds solonetz and to establish precisely expressed self-land improvement of solonetz during their evolution fromcrustal to deep. Degree of application - results of the work are introduced in the research work of the Crimean research center of the Institute of hydraulic engineering and land improvement of UAAS and the State design and survey institute on meliorative and water-economic construction. Separate positions of the dissertational work are used in the educational process at teaching discipline of soil science with bases of geology. The field is scientifically-educational and nature protection.