The effect of point application of fertilizerson the soil environment of spread line windrows in the Krušné hory Mts

The plateau of the Krušné hory Mts. belongs to areas that suffered the greatest damage caused by air-pollution stresses in Europe. A part of cultural practices aimed at the reconstruction of local mountain forests was the inconsiderate use of bulldozer technologies for the preparation of sites for forest stand restoration. In the course of large-scale scarification the top-soil horizons were moved into line windrows, which caused marked degradation of the soil environment. The present revitalization of the soil environment is based on the principle of spreading these man-made windrows. Experimental plots were established in localities affected by scarification; the organomineral material from windrows was superimposed on them and subsequently they were reforested with Norway spruce (Picea abies [L.] Karst.). In 2005 the point application of fertilizer tablets of Silvamix type in three treatments and calcic dolomite was performed into the rhizosphere of plants. Before fertilization and after three years of the experiment soil samples were taken from the organomineral zone of the root balls of plants, and the condition of the soil environment on spread windrows and changes in pedochemical properties as a result of applied fertilization were evaluated. Three years after the windrow spreading the content of the majority of soil macrobiogenic elements (N, K, Ca, Mg) is at the level of medium-high to high reserves, and only the low phosphorus reserves pose a certain hazard. The organomineral substrate of spread windrows is a suitable growth environment for the root systems of target tree species. The proportion of humus substances is the most important factor in spread windrows from which the characteristics of the other parameters of soil are derived. Along with the higher proportion of humus substances in Špičák locality significantly higher reserves of major macrobiogenic elements (N, P, K, Ca, Mg) were determined. The applied fertilizers of Silvamix type significantly increased the reserves of soil P, K, Ca, Mg and are a suitable means for the stimulation of spruce plantations in the restored environment of the Krušné hory Mts. Silvamix Forte fertilizer tablets are the most complex fertilizer with the most balanced effects that significantly increases the reserves of soil P, Mg and K. This fertilizer has a high effect on an increase in the reserves of soil phosphorus that may be deficient in conditions of spread windrows. Silvamix R is the most efficient fertilizer to increase potassium reserves. A positive effect of calcic dolomite on an increase in Ca and Mg content was observed while no such effect on the other elements was recorded.