The aim of the study was to determine the agricultural usefulness of the ashes obtained following the combustion of wood of fourteen tree species (pear tree, apple tree, aspen, ash, alder, birch, poplar, hornbeam, pine, common walnut, oak, hazel, bird cherry and spruce) in home fireplaces. The...

Modern agricultural technologies have contributed to a significant reduction in the amount of soil organic matter. Brown coal waste (BCW), with low energy content, can be used to neutralize this process, contributing to the recuperation of soil fertility and to environmental protection. More studies need to be conducted on organomineral fertilizers based on BCW and applied to soils with low humus content. Apart from increasing soil production capacity in arable fields, BCW could be used for the reclamation of industrially contaminated areas and degraded soils, in the vicinity of motorways and in soilless agriculture. It can also be used as a sorbent of gases emitted from slurry during its storage such as NH₃, H₂S, mercaptans, volatile fulvic acids (FAs); as a component of sewage sludge compost; as a natural additive to calf feed; and for the production of adsorbents for sewage and wastewater treatment.

A field experiment was carried out in 2016–2018 in a white lupin (Lupinus albus L.)-winter wheat (Triticum aestivum cv. ‘Bogatka’) crop rotation. The aim of this study was to determine the amount of nitrogen (N) that was biologically fixed by the white lupin crop in the first year of the rotation and to estimate how much of this N was then taken up from the lupin residues by winter wheat in the second and third years of the rotation. Biologically fixed N was determined by the isotope-dilution method (ID¹⁵N) by applying 30 kg N ha⁻¹ of ¹⁵N-labeled fertilizer (¹⁵NH₄)₂SO₄ (containing 20.1 at.% ¹⁵N) to the white lupin and the reference plant spring wheat. The yields of white lupin seeds and crop residues were 3.92 t ha⁻¹ and 4.30 t ha⁻¹, respectively. The total amount of N in the white lupin biomass was 243.2 kg ha⁻¹, which included 209.3 kg ha⁻¹ in the seeds and 33.9 kg ha⁻¹ in the residues. The ¹⁵N-labeled residue of white lupin was cut and ploughed into soil. Our results indicate that 111.2 kg N ha⁻¹ was fixed from the atmosphere by the lupin plants, with 93.7 kg ha⁻¹ found in the seeds and 17.5 kg ha⁻¹ in the residues. In the second and third years of the rotation when winter wheat was cultivated, the plots were divided into two groups of subplots (1) without N-fertilization (control) and (2) with an application of 100 kg N ha⁻¹. In the first year of winter wheat cultivation, 20.0% and 21.0% of N from the crop residues was taken up by the control and N-fertilization plots, respectively, while in the second year, uptake was lower at 7.12% and 9.27% in the control and N-fertilized plots, respectively.

Open Access Agricultural Journals published by Institute of Agricultural Economics and Information

This study examined changes in soil enzymatic activity caused by constant mineral fertilization with NPK and diversified fertilization with Fe and Mo micronutrients. A field experiment was conducted in a completely randomized design with four replications in Siedlce (central-eastern Poland) between 2012 and 2014. Alfalfa (Medicago sativa L.) was used as the test plant. The first factor consisted of fertilization treatments: control; NPK; NPKFe1; NPKMo1; NPKFe1Mo1; NPKFe2; NPKMo2, and NPKFe2Mo2. The second factor was composed of the time of soil sampling (15 August 2012, 20 September 2012, 17 June 2013, and 20 July 2014). Mineral fertilization was applied: N-20; P-22; K-124.5; Fe1-0.5; Mo1-0.5; Fe2-1.0; Mo2-1.0 kg ha⁻¹. Application of molybdenum (Mo2-1.0 kg ha⁻¹) in alfalfa fertilized with NPK was optimal for obtaining the beneficial nitrogenase activity. The applied NPKFe1Mo1 fertilization in alfalfa cultivation was optimized to achieve high dehydrogenases activity, alkaline phosphatase activity, and acid phosphatase activity. The highest of soil urease activity was determined in soil fertilized with NPKFe2Mo2. The biochemical index (BCHI) of soil fertility reached its highest mean value (254.9) after applying the NPKFe1Mo1. A high BCHI soil fertility index indicates the possibility of generating high alfalfa yields and maintaining good soil culture.

A field experiment was conducted in years 2016-2018 in crop-rotation: faba bean-winter wheat-winter wheat. After seedling emergency (2016) mineral fertilizer (¹⁵NH₄)₂SO₄ having 20.1 at% ¹⁵N (dose of 30 kg N ha⁻¹) was applied. The faba bean biomass contained 194.1 kg ha⁻¹of nitrogen (140.0 kg of N in seeds and 54.1 kg in crop residue). In this amount including 58.7 kg N ha⁻¹ in seed and 21.2 kg of N from air. Crop residue were ploughed into soil. Plots with winter wheat cultivated after faba bean (2017) were divided on two sub-plots 0 and 100 kg N ha⁻¹. Overall, winter wheat cultivated for two subsequent years took up from total nitrogen of crop residue 16.1 kg ha⁻¹ of N from control and 29.8 kg ha⁻¹ fertilized objects, but from biologically fixed nitrogen 6.29 and 11.6 kg ha⁻¹, respectively. Applied fertilizer contained 5.920 kg ¹⁵N ha⁻¹ from which 1.577 kg ¹⁵N ha⁻¹ was cumulated in faba bean seeds, 0.662 kg ¹⁵N ha⁻¹ in crop residue (sum 2.239 kg ¹⁵N ha⁻¹), 0.195 kg ¹⁵N ha⁻¹ and in winter wheat harvested (2017) and 0.084 kg ¹⁵N ha⁻¹ in winter wheat harvested (2018).