Регулирование состояния насаждений на антропогенно преобразованных территориях: принцип дендрологического разнообразия

Abstract

In low-forest areas with a poor natural of woody vegetation, the ecological capacity of the territory is increased by the introduction of the forest plantations for various purposes, which contribute to the regulation of phytosanitary conditions and the preservation a biodiversity of the regional. Among the ecological-adequate methods for the preservation of ecological optimum in the systems of multifunctional plantations of various purposes are importance of fundamentally: the inclusion of adapted entomophilic and fruit-bearing tree and shrub species, the creation of ecotonic zones of abundant flowering herbs and other landscape-ecological elements. Optimization of the phytocoenotic situation expands environmental preferendum beneficial insects, their attracted by the possibility of additional supply and new safe havens creation for the entomophages its expanded a food range and the use in foods not typical for them types of pests. Collection of material was carried out in the forest plantations of various a special purposes. The objects of the study were useful insects. A samples have been taken by the mowing trees of crowns by the nets of entomological , a visual inspection of the model branches and the manual collecting of predators and phyllophages with species of parasite with the subsequent by cultivation of adult insects in the laboratory conditions. Stabilization of the ratio of harmful and useful insects in the communities is facilitated by the introduction of forest plantations into the landscapes. In this regard, many atypical species of insects in the forest-equipped areas is expand their food spectrum, using non-specialized a species of pests. The number of individuals of parasitic insects here increases by an average of 4.0 times, the abundance of predators increases by three times, the density of economically dangerous pests is reduced by 1.5-4.0 times. Against field pests (harmful bugs and grain flea beetles) the biocenotic role of forests plantation is most pronounced. Their number on forest-protected crops is reduced by 4.0 and 3.5 times, respectively. The increase in dryness of the climate provokes an increase in the density of pests (by 41-96%) and a reduction in the number of their natural enemies (by 16-28%), with the total number of insects increasing by 11-31%. The diversity of dendroflora is determines the effectiveness of action the parasites and predators. Most of the entomophages (28.0% of the total number of useful arthropods) are concentrated in the plant crowns сем. Rosaceae. Attractiveness of plants Sambucus и Lonicera for the parasites and predators are less pronounced – their number here is on average 4.0-10.0 times lower. The complexity of the structure of phytocenosis with the inclusion in the composition of landings blooming profusely woody species increases a exchange the faunal by the facies and strengthening of the complex of the entomophages in the gradient of vertical. Optimization of phytosanitary conditions in the forest stands of different purpose is based on the selection of adapted tree species, positively changing fitered and contributing to the preservation and enhancement of biocenotic relations, biodiversity, restoration of natural mechanisms of self-regulation and, as a result, stabilety functioning of the forest reclamation complexes. Increasing dryness of the climate in the southern direction affects the diversity and abundance of faunal communities of forest reclamation complexes. Zonal of affiliation the communities of entomofaunal to the more arid areas leads to an increase in the total number of insects on 11-31%. Positive effect for a harmonious the entomofauna of community, with an adequate ratio of harmful and useful component, is fold to the areas adjacent to planting - the state of ecological stress. On remote site from the direct influence the forest plantation areas is manifested ecological regression.