Chernyshenko S. Dynamics of forest biogeocoenoses of Ukrainian steppe zone (nonlinear processes: successions, information interactions, revegetation).

The object is forest biogeocoenoses of Ukrainian steppe zone. The objective is research of dynamics of forest ecosystems in conditions of the steppe zone within problems of nature protection and nature management, elaboration of corresponding nonlinear models, analysis with their use of forest biogeocoenoses development; the statement and study of optimization of dynamics of natural and artificial forests. The methods are ecological, statistical, information, optimization, methods of the systems and structural-functional analysis, mathematical modelling, computer simulation. A base set of nonlinear models for forest development description has been elaborated. Principles of nonlinear biogeocoenology, as a science of nonlinear dynamic effects in ecosystems and their mathematical modelling, are formulated; applications of the new principles in the forestry have been considered. Features of populations' competitive interactions are studied as a basis of successions. A classification of populations' competitive strategies is elaborated; new models of main form of successions are created. A system analysis of successions has been carried out on the base of A. L. Belgard's amphicoenose theory and his forest typology. A role of biogeochemical cycles for forming nonlinear forest dynamics are analysed. A model of amphicoenose, as a system of antagonistic biological cycles, is elaborated. Problems of artificial forests' cultivation in the steppe zone conditions have been formulated on the base of the amphicoenose theory and the technogenic biogeocoenology. Optimisation algorithms for different models of forest revegetation have been proposed and tested. Use of the proposed system and information approaches has been illustrated by the examples of investigation of special ecological problems of the steppe Pridniprovye, such as bioindication of technogenic pollution, prediction of pollutants' migration in food webs, etc.