Landscape-ecological investigations were made in 2011–2012 and 2014 at the topological level on the territory of the Komsomol’skii Zapovednik (Nature Reserve), a model study area of the boreal ecotone of the Lower Amur region. Sixty-five trial areas were established and comprehensively described. The types of local forest natural complexes were identified, which characterize the hierarchical system of natural-territorial organization of the boreal ecotone of the Lower Amur region. The empirical data obtained were analyzed by using the methods of information theory. A general information-statistical model of chain reactions in intercomponent relationships was developed as well as the partial models of binary ordination providing insight into the mechanisms of intercomponent interactions within the forest topogeosystems of the territory under investigation. A large-scale landscape map (sc 1:100 000) was compiled for the Komsomol’skii Zapovednik on the basis of geomorphometry methods. V. B. Sochava’s well-known concepts regarding the structure and functioning of geosystems at the topological level as well as forest-forming processes on the territory of the Lower Amur region are expanded. The regularities in the formation of buffer forest communities characteristic for the forest geosystems of the boreal ecotone of the Lower Amur region are presented in detail. The study revealed and quantitatively assessed the main topological features of the monosystem organization of the forest geosystems on the study territory. It is established that the structure of the forest topogeosystems of this territory is largely influenced by the slope exposure and altitudinal zonality and lithology of bedrocks in the presence of clearly pronounced circulation processes. A framework was developed for a local geosystem monitoring on the territory of the Komsomol’skii Zapovednik as well as for forecasting of future functional and structural changes in forest geo(eco)systems.Keywords: structure, functioning, groups of landscape facies, groups of forest types, landscape-ecological relationships.