Czy zakładanie upraw dębowych metodą biologicznej racjonalizacji sprzyja zachowaniu leśnych zgrupowań skoczogonków (Collembola, Hexapoda)?

Alternative methods of oak cultivation aim at reducing the cost of establishment of young plantations and decrease in the expenditure on their tending. In these methods, the corridors consisting of oak seedlings planted in the rows or isolated groups of twenty six seedlings are enclosed by stripes or patches without intervention left for natural succession. The restriction in site preparation on these areas and spontaneous development of young generation of trees are assumed to create favourable conditions for many forest organisms and, in results, significantly improve biological diversity of the managed forests. The aim of the study was to recognize the response of forest collembolan assemblages on alternative methods of establishment of oak plantations. The study was performed in the Forest Experimental Station in Rogów (Central Poland). In a mature stand on moderately humid mixed deciduous forest site, on clear−cut and on oak young plantations made by corridor and tree groups methods, fifteen study plots were established. In case of young plantations, these plots encompassed both artificially planted corridors or tree groups and adjacent fragments of plantation left for natural succession. Soil samples were taken in June and September 2014 and, using a simplified Tullgren apparatus, 18 thousands of collembolan specimens belonging to 84 taxa were identified. Our study proved that clear−cut and site preparation by rotary tiller on moderately humid mixed deciduous forest had a negative impact on Collembola assemblages, because caused a reduction in species number and abundance. However, the establishment of oak plantations by alternative methods, consisting in abandonment an artificial planting on some patches of renewed plots, significantly mitigate negative effects of clear−cut and reforestation on collembolan assemblages. The species number and abundance of springtails on patches left for spontaneous succession were distinctly higher than in artificially planted corridors or groups of trees in case of all studied plantations. Furthermore, it seems that corridor method in oak plantations establishment is advantageous for forest springtails, because the number of specimens per square meter on corridor plantation was higher than in tree group method. The beneficial effect on soil fauna of alternative methods of oak cultivation described in this paper weighs in favour of their wider application in silviculture.