Analysis of the aerial application of fertilizer and dolomitic limestone

The paper evaluates the quality of revitalization treatments (fertilization and liming) carried out in selected areas within Forests of the Slovakia (state enterprise) during the year 2008. Revitalization treatments were carried out in declining Norway spruce forest stands in different site conditions. Full-scale aerial technology (helicopter and crop duster) was applied. The aim of the study was to find out the total amount and its variability of both fertilizers and dolomitic limestone after their application. The analyses revealed significant differences between the amount of fertilizer and dolomitic limestone which was applied to selected areas and the required amount (norm). As for fertilization, the largest difference was found in Mg on Saling area (the amount of Mg reached only 7%+/-0.5 of the norm) and in Zn on Ladova area (only 8%+/-1 of the norm). The required amount according to the norm was approximately met in B on Ladova area (65%+/-10 of the norm). Yet, a significantly lower amount of fertilizers than the required one was revealed on all selected areas. After the application of dolomitic limestone to Liptovska Teplicka area the significantly lower amount than the required one was found out (72%+/-12 of the norm). On the other hand, the significantly higher amount of dolomitic limestone than the required one was determined on Smolnik area (143%+/-27 of the norm). Results also show the huge spatial variability of both fertilizers and dolomitic limestone on all selected areas (from 40% up to 100% between collecting places, and up to almost 170% between collectors within the collecting places). Such high variability of applied fertilizers and dolomitic limestone and the lower total amount than the required one will influence the effect of revitalization treatments.