The content of manganese in soddy brown soils of the Transcarpathian Mountain Valleys

Abstract

The soil covering of Transcarpathia, which is used for cultivation of crops, is rather heterogeneous as to genetic features of soils. This is mostly caused by the climatic conditions of corresponding natural zones. Brown mountain soils, soddy brown soils, meadow brown soils and mountain meadow soils have originated in mountainous areas on mountain ranges and slopes of different altitude, which are different in terms of mechanical makeup and are well drained. They are characterized by high content of inaccessible humus (in which fulvic acids predominate), acid reaction of soil solution and evident diversity in provision of mobile forms of nourishing chemicals. On the average, the reaction of soil solution is 4,60 pH of a salt solution, in the case of hydrolytic acidity – 4, 28 me/100g of soil, which characterizes them as semi-acidic. The aim of our thesis is to research the level of manganese, which is one of essential and toxic elements for plants, depending on its concentration in soil, in soddy brown soils of the mountainous zone of Thranscarpathia, and also its distribution in profile of soil horizons. To carry out this aim, samples of soil were chosen by random selection. Total manganese in the soil was determined by the method of mass spectrometery. The samples were extracted by hydrogen peroxide, chlorohydric and azotic acids (ext. p.). Dissolution of the samples was carried out using microwave sample preparation system. Active forms of manganese were extracted by generally accepted extragents: water-soluble extragent – deionized water; free forms of manganese – ammonium acetate buffer solution рН 4.8 according to M. K. Krupskyi and H. М. Alexandrova. Afterwards, the samples of soil were analysed using the method of mass spectrometery. According to the results of the research, the max. total of the manganese is observed in the mineral upper humus-accumulative horizon, but if you make a transition to the parent rock, it decreases. According to the quantitative research on determining free forms of manganese, it can be observed that soddy brown soils of the researched region are provided with the mobile forms of manganese both in the upper humus horizon and in lower transitional humus horizon. Moreover, the humus horizon of the observed region has a high content of mobile forms of manganese, which constitutes >20,1, and in the transitional horizon to the parent rock the provision index is high. A considerable increase in the water-soluble manganese in the upper humus horizon was also observed. Its concentration is considerably decreased with a transition to the lower humus horizon. The research data confirms that soddy brown soils of the observed region are contaminated with manganese compounds.