Lakusta O. C : N : P - Stoichiometry of river ecosystems

The dissertation is devoted to the study of the features of CNP-stoichiometry of river ecosystems and it identify of the role of environmental factors in its regulation.The mean and background C : N : P values for water and seston of the river ecosystems of the model region are established. A comparative analysis of basin, seasonal and annual variabilities of CNP-ratios in water and seston of the river ecosystems has been carried out. The abiotic and anthropogenic factors that have direct or indirect effects on CNP stoichiometry of the river ecosystems are revealed.The direct and reciprocal relationships in the regulation of CNP-balance in the system of "river water - living organisms" are investigated with the use of laboratory microcosms . The dependencies between CNP-stoichiometry of river ecosystem water and the structure of trophic networks established in the work will contribute to a deeper understanding of causal-effect relationships in case of disturbance functioning of this ecosystem types.