Changes in soil properties and possibilities of reducing environmental risks due to the application of biological activators in conditions of very heavy soils

This study aims at verifying the effect of farmyard manure (FYM) and of selected activators (Z'fix and NeoSol) on changes of soil properties. Their application should lead to improvement of soil physical properties and of organic matter fixation, to reduction of environmental risks, e.g. of tillage energy requirements. Experimental variants (0.7 ha each) were as follows: I (FYM with Z'fix); II (FYM with Z'fix + NeoSol); III (FYM); IV (Control NPK only). FYM was applied at rates: 50 t ha-1 (2014); 30 t ha-1 (2016). Additional NPK fertilizer (I–IV) was applied according to annual crop nutrient normative. The agent Z'fix was used as an activator of FYM biological transformation (5.5 kg t -1 ). The agent NeoSol was used as soil activator (200 kg ha-1 ; annually). In order to verify the effect, cone index, bulk density, tillage implement draft and chemical soil components (Humus, C/N ration and Ntot) were measured annually. Compared to the control, the application of FYM combined with the mentioned agents (I–III) increased Ntot more than two times. Moreover, it decreased (I–III) bulk density by 8.7%. Tillage implement draft decreased by 3% after the application of FYM with Z’fix (I, II). The study confirmed that FYM application combined with utilization of activators positively influenced soil fertility and helped to reduce environmental risks

Leaching of mineral nitrogen in the soil influenced by addition of compost and N-mineral fertilizer

This paper deals with the problem of mineral N leaching from arable lands due to the fertilization method. The influence of different doses of compost (50 and 100 Mg ha−1) and N-mineral fertilizer (35-70-140 kg N ha−1) on leaching of Nmin in a lysimetric experiment with winter wheat. The area of our interest represents the main source of drinking water for the city of Brno and its neighborhoods. To demonstrate the effect of compost and mineral nitrogen addition, the lysimetric experiment was established there. Seven variants of the experiment with different fertilization schemes were studied during two vegetation seasons (2013 and 2014), each with three repetitions. The experiment was carried out in plastic experimental containers of 0.3 m diameter and 0.5 m height. Therefore, each lysimeter was the same size and was filled with 25 kg of subsoil and 25 kg of topsoil. The highest leaching of Nmin was detected in the variant C2 where 140 kg N ha−1 was applied, in both vegetation periods (5.97 kg Nmin ha−1 after the first vegetation period and 17.02 kg Nmin ha−1 after the second vegetation period). The positive effect of compost application (individually or in combination with the mineral N) on decrease in mineral N leaching was found during both vegetation period in comparison with variant C2. The highest doses of compost (100 Mg per ha) significantly decreased the concentration of mineral nitrogen in the soil eluate in both periods (3.03 kg Nmin ha−1 and 5.79 kg Nmin ha−1, respectively), by 197% and 293% in comparison with variant C2. There is evidence that the application of compost has a positive effect on the reduction of Nmin leaching