СARBON POOL AND BIOLOGICAL ACTIVITIES OF SOILS IN DIFFERENT ECOSYSTEMS

The content and stocks of carbon and the activity of microbiological destruction of organic matter in three types of chernozem soils in Ukraine have been investigated. An imbalance was found in the accumulation of the main components of the soil organic matter, as well as between mineralization processes, humus accumulation and degradation of cellulose in arable soils and their natural analogs. In the soil of natural ecosystems, the processes of mineralization -immobilization, destruction of organic matter and humus accumulation are balanced, which is confirmed by a high carbon pool (Сtot) and a fraction of Сmic in Сtot. In the soil of natural ecosystems processes of mineralization-immobilization, destruction of organ resources and humus-accumulating are balanced, which is confirmed by high-quality carbon pool and partial Сmic in Сtot. In agroecosystem is going destabilization of organic matter in the soil, which leads to a decrease of humus content in 1.1-1.5 times, stocks of organic matter - in 1.3-1.8 times. In arable soils, part of Соrg in the total soil carbon pool is 80-82% and 92-94% in the soil of the natural ecosystem. The losses of Соrg from chernozem soils in agroecosystem are 19-29% and this is due to a significant reduction in the content of Сmіc (63-71%). The application of different fertilizers causes destabilization of the soil microbial community, reduces microbial productivity and activates mineralization processes of organic matter, which leads to loss of Соrg and a decrease in the total carbon pool (Сtot) in the soil by 6-18%. The soil of natural ecosystems is characterized by a high content of Сmіc in the Соrg (3.14-3.70%), which indicates a high microbial productivity and fixation of organic substances in biomass of microorganisms. In the arable soils, was the low content of Сmіc in the organic matter of the soil (1.19-1.52%) which indicates the predominance of mineralization processes over the processes of humification. The application of exogenous mineral substances in the soil activates the processes of mineralization (Кmіn increases by 7-18%) and provides a high degree of using by microorganisms of soil organic matter (Кped increases by 6-9%). Organic fertilizers contribute to the formation of a maximum microbial pool, optimizing the structure of soil microbial community, decrease the intensity of mineralization processes (Кmіn) by 15-29% and the decomposition of soil organic matter by 6 to 37%. A significant difference in the parameters of the potential cellulolytic activity of the soil in the natural ecosystems and agroecosystems had been established. At the same time, the soil of natural ecosystems is characterized by a slight fluctuation of the emission СО2 (3.3-4.4 mg СО2 / kg of soils per day).