Summary:

The aim of the study was to determine the influence of mulching and or-ganic fertilization on growth parameters of one-year old Scots pine seedlings as well as on the occurrence of soil mites (Acari) under conditions of irrigation. Fe-licity of proposed revitalization measures was conducted with the use of the bio-indication method. In this investigation the indicatory organisms were mites, common and very numerous in forest soils. The experiment was carried out in forest nursery Bielawy (Forest Inspectorate Dobrzejewice). The slightly loamy sand was predominant on the studied area. Experiment was design as two-factorial trial (split-plot), replicated four times. The first row factor was organic fertilization used in the two treatments (main plots): without organic fertilization-control, organic fertilization with compost from forest cap - humus applied before sowing of Scots pine seeds (spring 2008). The second row factor was mulching used in the two treatments (subplots): without mulching - control, mulching with fresh cap-humus from habitat of fresh coniferous forest, which was applied after seedling emergence (September 2008). Influence of both the two investigated factors (organic fertilization and mulching) on the growth indices of seedlings was insignificant. It was observed that seedlings cultivated on the plots fertilized with compost and mulched were characterized by slightly increased height and diameter. On the basis of the statistical analysis it was found that the mulching distinctly influenced the number of mites, including Actinedida, Gamasida and Oribatida, as well as on their species diversity. In case of the total number of mites as well as the species number and species diversity of oribatid mites, the interaction of mulching/organic fertilization was found. The preliminary investigation on the estimation of the biological activity of soil with the use of the bioindication method can indicate the considerable felicity of the conducted revitalization measures in the forest nursery. The final estimation of these measures can be conducted only after two years of investigation.