The object of this study was to compare the results obtained with four methods of determination of cation exchange capacity (CEC) and sum of exchangeable cations (Ca, Mg, K) in soils. One of these methods is Kappen’s method and the others methods are based on different extracting reagents: sodium acetate (pH = 8.2), barium chloride and hexaamminecobalt(III) chloride. Values measured with barium ions and hexaamminecobalt(III) ions as index cations are very comparable and these two methods can be considered as equivalent. Kappen’s method gives overestimated results, especially for acid soils reach in organic matter and very calcareous soils. Sodium acetate, buffering the pH of the extracting solution, causes increase of numbers of negatively charged sites and particularly those bonded to organic matter and for this reason values obtained with this method are overestimated. Nevertheless, it is possible to correct this error for a given soil sample by regression equation considering pH of soil, clay and organic carbon content.

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...

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

Peat organic soils play a major role in the accumulation of soil organic matter (SOM) and the mercury (Hg) cycle. Large mercury resources in peatlands can be a source of methylmercury for many decades and centuries, even if deposition is significantly reduced. The organic matter of peatland soils drained for agricultural use is subject to secondary transformation, which may affect the accumulation and resources of mercury. The aim of our work is to assess the secondary transformation of organic matter in the soils of drained peatlands of the temperate climate zone and to examine whether it affects mercury resources and profile distribution in organic soils. Field research was conducted in peatlands located in eastern Poland. In the present study, evaluation of secondary transformations occurring after drainage was based on observations of soil morphological characteristics, physical and chemical properties as well as fractional composition of organic matter of the identified soil horizons (to depth 70 cm). Standard cold vapor atomic absorption spectrometry (CV-AAS) was used to measure the total mercury content. In our research, we found a significant effect of the secondary transformation of organic matter occurring in drained peatlands of the temperate climate zone on the total mercury content and stock in soils. The highest content and differentiation of mercury occurred in murshic horizons (up to a maximum depth of 43 cm). The average mercury content of the distinguished soil horizons is grouped in the following series (in μg kg⁻¹): M1 (212.0) > M2 (182.8) > M3 (126.3) > Pt (84.9). The mercury stock, up to a depth of 70 cm in the tested soils, ranged from 17.5 to 39.6 mg m⁻². As much as 82.2% of soil mercury was found in the upper murshic horizons. We found strong correlations between soil properties characteristically variable in the secondary transformation process and total mercury content. The increased content of humic substances in murshic horizons caused a significant increase in the total mercury content. Our research is of great importance for soil monitoring, as the amount of determined mercury was greatly influenced by the depth of sampling (up to 25 cm). The results of the research should be taken into account when planning the restoration of peatlands of the temperate climate zone. There is a potential risk that elevated mercury concentrations in the upper murshic horizons may be a source of methylmercury for a long period of time. In peat soils with a high concentration of mercury, the risk of contamination with this toxic metal should be determined before re-irrigation.

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.

Copper is an element necessary for the proper growth and development of plants, but when taken in excess amounts, it can be toxic. Its availability for plant can be reduced by using organic fertilizers or soil liming. The aim of the study was to investigate the effect of increasing doses of copper (100, 200, and 300 mg Cu·kg⁻¹ of soil) application in combination with various organic amendments (cattle manure, chicken manure, and spent mushroom substrate) on the yield of cocksfoot and its content and uptake of this metal, and to determine its coefficient of bioaccumulation and tolerance indices. The toxic effect of copper manifested by significant decrease in the yield of the test plant was after the application of 300 mg·kg⁻¹ of soil. Increasing doses of copper application increased its content and uptake by the test plant, while observing the decreasing bioaccumulation factor. All the soil amendments reduced the toxic effect of copper on cocksfoot. The most effective organic amendment in terms of yield and protective effects against high levels of copper was cattle manure, in the case of which the Org/Cu and Cu/Org tolerance indices were highest.