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In a multi-year field fertilisation experiment the effects of organic and mineral fertilisers on the physicochemical properties of lessive soil were compared. Manure, two doses of slurry and mineral fertilisers were applied to soil farmed in an eight-field crop rotation. Dose 1 of slurry, manure and mineral fertiliser were applied in doses balanced with nitrogen. Dose II of slurry was determined so that the amount of organic carbon introduced along with it was the same as in the dose of manure. To the experimental facilities with manure and slurry, additional fertilisation with phosphorus and potassium was applied. Following 36 years of annual fertilisation, samples of soil were taken from the 0-25 cm layer, determining the amount of organic carbon and the sorption properties of the soil. It was determined that as a result of applying organic fertilisers, the amount of organic carbon, sorption complex capacity and basic cation content increased whereas hydrolytic acidity decreased. Manure was found to have the most beneficial effect, which was matched by neither dose I nor II of slurry. Additional phosphorus-potassium fertilisation of soil with manure and slurry positively influenced the sum of bases and the total sorption capacity of the soil. Mineral NPK fertilisation led to the decrease in the saturation of bases of the sorption complex and the increase in hydrolytic acidity.
The aim of the present research was to determine the total selenium content in soil and plants from a microplot experiment with different nitrogen fertilization regimes, and to identify the relationships of the selenium content in soil and plants versus the soil catalase activity. The experiment was conducted in randomized blocks with three replications. The soil and plant samples were collected from a microplot experiment established at the IUNG in Pulawy. The soil was enriched with mineral nitrogen and with nitrogen supplied in slurry, both applied at doses of 100 kg N ha-1. The total selenium content in soil under each of the crop rotation systems was no more than 0.2 mg kg-1. Data from the references imply that the soil was deficient in selenium. The highest amount of selenium was under winter wheat and spring barley with undersown crop in crop rotation A, and in soil under maize crop rotation B. Slurry fertilization significantly stimulated the activity of catalase in soil, as compared with the control and mineral nitrogen fertilization treatments. The highest catalase activity – nearly double the control – was detected in soil under winter wheat in crop rotation A and under spring barley in crop rotation B; winter wheat, regardless of the type of crop rotation, accumulated on average 0.3 mg Se kg-1 d.w. in aerial parts and 0.344 mg Se kg-1 d.w. in roots. The highest amounts of selenium in the investigated parts of plants were reported in the control plots and in the plots with slurry fertilization. Mineral fertilization reduced selenium availability to plants. In both crop rotation systems, the highest bioaccumulation of selenium was noted in winter wheat roots from control plots, while the lowest one was detectetd in aerial parts of plants from the plots with slurry fertilization. Despite the fertilization applied, the selenium content in plant roots was higher than its content in aerial parts. The correlation analysis of the results on selenium concentration in soil and plants as well as the catalase activity of soil identified only a significant dependence between the total selenium content and catalase activity in soil from crop rotation B.
In our study conducted in north-central Poland in 2001-09 in the lessive soil of a very good rye complex, a relationship between the yielding of tansy phacelia and common sunflower grown as stubble catch crop and the weather conditions that prevailed during the growing period were estimated. The yield of the tested plants grown as stubble catch crop was significantly dependent only on the total precipitation occurring in the period from the beginning of July to the end of August. A good plant supply in water in one of those two months was sufficient to cultivate the catch crop successfully, and optimal total precipitation from the beginning of July to the end of August was 142 mm for tansy phacelia and 150 mm for common sunflower.
In Poland 11% of soils feature elevated zinc content or slight zinc contamination. This investigation aimed at estimation of the effect of progressive acidification of slightly zinccontaminated soils on zinc content in plants and translocation of this metal downwards the soil profile. The study involved a two-year lysimetric experiment on lessive soil. The amount of zinc indicating slight soil contamination was introduced into 0.2 m of topsoil, which was subjected to progressive acidification with sulfuric acid solution in the course of the experiment. Zinc content proved to considerably increase in plants (barley straw and maize) only under strong acidification. Soil reaction did not significantly influence the zinc content in soil, both total and assayed in HCl zinc forms, while a considerable increase in easily soluble zinc forms (in CaCl2 solution) occurred on strongly acidified soils. Considering the whole research period, increasing soil acidification did not result in any alterations involving zinc content in Bbr and C horizons of soil profiles (below 30 cm).
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Copper speciation in different-type soil profiles

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Determination of the total content of metals in soils does not give enough information about their mobility and potential uptake by plants. The influence of heavy metals on plants depends on the type and form of a metal as well as properties of soil. The aim of the research was to evaluate the influence of soil type (Rendzic Leptosols, Haplic Luvisols, Haplic Arenosols) on the content and speciation of copper in soil profiles. The research was carried out in two physiographical regions: Lublin Upland and Sandomierska Valley. Samples were collected once from individual genetics horizons, in total from 30 typological differentiated soil profiles, made from chalk marl, loess and sands. Speciation analysis of copper was carried out with the use of a three-stage sequential method of fractionation, which can isolate four fractions with BCR: fraction I – forms soluble in water, exchangeable and bounded with calcium carbonate, extractable with CH3COOH; fraction II – forms bound with free Fe and Mn oxides, extractable with NH2OHHCl; fraction III – forms complexed with organic matter, hot extractable with 30% H2O2 and next the mineralization products reextractable with CH3COONH4; fraction IV – residual forms (residue), i.e. the difference between the total content and the sum of three fractions I – III. The speciation analysis indicated that in all the examined soil types, the residual form showed the largest share of copper in its total content, followed by forms bounded with organic matter and, containing the smallest proportion of copper, the soluble, exchangeable and bound with calcium carbonate forms. In rendzinas and lessive soils, the content of fraction IV in the humus horizons was significantly higher than in the parent rock, whereas in Haplic Arenosols the host rock was richer in this copper form than the humus horizons.
β-glucosidase (E.C. 3.2.1.21), an enzyme involved in cellulose degradation, plays an important role in the soil organic carbon cycle. Cellulose is the most abundant organic compound in the biosphere so a product of its enzymatic hydrolysis is important as an energy source for soil microorganisms. Since β-glucosidase is very sensitive to different factors, determination of its activity might be helpful in soil quality monitoring. The objective of the study was to assess the effect of various doses of farmyard manure (FYM) and mineral nitrogen on β-glucosidase activity in soil samples taken under winter wheat cultivated in crop rotation systems depleting soil from organic matter (A) and enriching soil in organic matter (B). Soil samples were taken in 2002 from a two-factor fertilization experiment carried out as randomized sub-blocks cropped with winter wheat cultivated on lessivé soil. The experiment was located at the Experimental Station of the Institute of Tillage and Soil Science in Grabowo on the Vistula River. All fertilization combinations included FYM (0, 20, 40, 60 and 80 t.ha–1) and nitrogen fertilization (0, 40, 80 and 120 kg ha–1). The activity of β-glucosidase was determined according to Eivazi, Tabatabai (1988). The enzyme activity ranged 3.604-7.041 mM pNP g–1 h–1 in soil samples taken from crop rotation A and between 4.931-7.445 mM pNP g–1 h–1 in those collected from the crop rotation enriching the soil in organic matter. These data were closely related to the applied FYM and nitrogen fertilization doses. Moreover, β-glucosidase activity depended significantly on sampling dates. Enzyme activity was closely connected with soil organic carbon and total nitrogen content, which was confirmed by highly significant correlation coefficients between these parameters (r=0.611-0.770 for Corg, and r=0.844-0.912 for Nog; p<0.01 and p<0.001).
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