Local Mechanisms of Formation, Functioning and Stability of Boreal-Forest Ecosystems

Abstract

Large-scale empirical-statistical modeling of boreal-forest ecosystems has been elaborated by the example of southern outpost of the boreal belt on the Russian Plain. The informational methods of calculation of component interconnections, distribution of ecological niches, and the measure of forest ecosystem stability are described. The general informational model is considered as a system of chain reactions in landscape connections under external hydro-thermal impacts. The revealed local ecological optimum of coniferous-forest phytocoenosis characterizes the zonal-regional norm of forest ecosystems formation and can serve as a reference point of different local responses to background impact. The mechanisms of autoregulation are conditioned by desuccessional drainage of the territory.
The destructive branch of biological cycle is the leading factor of exchange processes. The lithomorphization and hydromorphization are two competing abiotic factors. The maximum of net primary production is reached under conditions of enhanced hydromorphicity of soil-grounds. Four states of stability of forest ecosystems were revealed on the basis of phytomass turnover coefficient and litter-fall index. With reference to forest stability, the former parameter is much more effective as compared with the latter. Stability is differentiated depending both on individual geocomponents and on forest type groups. Interaction of abiotic and phytocoenotic factors creates a certain special order of the index of elastic stability of forest biogeocoenoses and more complicated landscape units – landtype associations.