Vašák F., Černý J., Buráňová Š., Kulhánek M., Balík J. (2015): Soil pH changes in long-term field experiments with different fertilizing systems. Soil & Water Res., 10: 19-23.The changes of soil pH in long-term 14-year field experiments with different fertilizing systems are described. The field experiments were located at four sites of the Czech Republic with different soil and climatic conditions (Červený Újezd, Hněvčeves, Lukavec, and Prague-Suchdol). At each site, the same fertilizing systems and crop rotation (potatoes -winter wheat -spring barley) were established. Six experimental treatments were applied to crop rotation: (1) unfertilized treatments (control); treatments with organic fertilization: (2) farmyard manure (FYM), (3) sewage sludge (SS); treatments with mineral fertilizers: (4) nitrogen (N), (5) nitrogen with straw application (N + straw), and (6) nitrogen with phosphorus and potassium (NPK). The long-term effect of fertilizers significantly depends on soil conditions. At the site Prague-Suchdol minimal differences in the soil pH were observed by all treatments. This is caused by the high buffering capacity of Chernozems against the soil acidification. At Červený Újezd (Haplic Luvisol), Hněvčeves (Haplic Luvisol), and Lukavec (Stagnic Cambisol) sites, soil pH decreased by all treatments. Only at Hněvčeves site the soil pH did not change with N treatment. The highest soil pH decrease in the treatment with NPK (ΔpH -0.89) and N + straw (ΔpH -0.70) was observed at Hněvčeves site. By the treatments FYM and SS the highest decrease was registered at Červený Újezd (ΔpH of about -0.30 and -0.63, respectively). The highest decrease in control treatment (ΔpH of about -0.63) was observed at Lukavec site. The results showed that to evaluate long-term soil pH changes a whole complex of factors must be examined.

The aim of this study was to evaluate winter wheat grain qualitative and yield parameters after the application of different organic and mineral fertilizers at two sites in the Czech Republic (S1 – Lukavec, S2 – Prague-Suchdol). For the purpose of this paper grain yield (GY, t ha−1), thousand kernel weight (TKW, g), bulk density (BD, g l−1), grain crude protein content (CP, %), and falling number (FN, s) were determined with regard to the CSN 461100-2 (2001) standard for food wheat. Significantly highest values of GY and BD at both sites and of CP at S2 were observed after the use of nitrogen in mineral form. At S1, significantly highest values of FN were obtained after the use of mineral fertilizers in combination with straw. The required limit of BD for food wheat was met for all fertilization treatments, while that of CP only at S2 by treatments with mineral nitrogen fertilizers. At S2, a strong correlation between all evaluated traits was registered. Low correlation was found at S1 between TKW and other evaluated traits.