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Model studies were carried out using the three-component CuCl2, CoCl2 and CrCl3 solution in two greybrown podzolic soils. After saturation of soil with the three-component solution and elution with water, desorption was carried out with the 0.1 mol dm-3 KCl solution. For comparison, desorption with the NH4Cl, CaCl2 and MgCl2 solutions was also conducted. Desorption of Cu2+ with K+ was in both soils similar to that of NH4 + and Mg2+ but smaller in comparison with Ca2+. In the case of Co2+ desorption with the studied exchangeable cations was not differentiated. Desorption of Cr3+ with K+ and NH4 + was greater than with Ca2+ and Mg2+. The differences in desorption efficiency can be explained based on the theory of hard and soft acids and bases (HSAB).
The objective of the study was to determine the direction, intensity and duration of changes in abundance and activity of certain microbial groups active in nitrogen transformations in soil subjected to a 4-year fertilization treatment with municipal and industrial sewage sludge. The study was conducted on podzolic soil, whose accumulation horizon had been fertilized in 1998 with fermented sewage sludge at doses of 30 Mg⋅ha-1(1%), 75 Mg⋅ha-1(2.5%), 150 Mg⋅ha-1(5%), 300 Mg⋅ha-1(10%) and 600 Mg⋅ha-1(20%) and planted with willow (Salix viminalis L.). Four years after the application of sludge, microbiological and biochemical analyses were made in two soil horizons (0-20 cm and 20-40 cm). It was found that in the soil from the 0-20 cm depth significant stimulation of the growth of proteolytic fungi and bacteria continued, but only under the effect of the highest dose of sludge. Moreover, there was a notable stimulation of protease activity and nitrification process alongside a slight inhibition of ammonification. In the soil from the 20-40 cm layer stimulation of the growth of protein-decomposing fungi was observed as well as that of proteolytic and nitrification activity of soil, while ammonification was inhibited. However, the effect of sludge was generally less pronounced in the deeper soil layer than in the surface soil horizon.
The paper presents seasonal changes in the concentrations of ammonia, nitrate and phosphate ions in podzolic soils under the Vaccinio uliginosi–Betuletum pubescentis and Empetro nigri-Pinetum plant communities. It results from the conducted investigations that the distribution and accumulation of mineral forms of nitrogen and phosphorus are considerably affected by atmospheric conditions such as temperature, humidity and precipitation. Analysed soils were characterised by a strongly acid reaction, which decreases with the depth of the soil profiles. A statistically significant correlation was found between the content of biogenic substances in soil and litterfall. The highest concentration of biogenic substances was observed in spring and summer months. Among analysed ions the ammonia form predominated, which mean content remained within the range from 0.12 to 6.69 mg/100 g d.m. Concentration of nitrates ranged from 0.05 to 0.13 mg/100 g d.m., while that of phosphates – from 0.04 to 3.09 mg/100 g d.m. The predominance of the ammonia and phosphate forms over the nitrate form in the organic horizons may result from their retention by the sorption complex. Nitrate ions exhibit greater mobility and are leached deeper into the analysed soil profiles.
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The main goal of this study was to investigate the effect of biochar on hygroscopic water content (maximum hygroscopicity) of grey-brown podzolic soil (Haplic Luvisol). The biochar was applied to the soil of sub-plots under fallow and grassland in the amount of 0 (control), 10, 20 and 30 Mg·haˉ¹. Soil samples were taken three times per year during the period of 2013-2015. Sorption isotherms of water vapour were determined for all studied samples and the maximum hygroscopicity (MH) was calculated from the relative water vapour pressure at p·p0ˉ¹ = 0.965. Value of the MH varied from 1.5 to 3%. The effect of biochar addition to soil on hygroscopic water content was ambiguous. Addition of biochar caused a slight decrease in MH value in the case of the grassland. For the fallow, a positive effect of biochar addition was observed.
Water vapour sorption processes on mixtures of soil and organic fertiliser Rosahumus (RH) were investigated. Mixtures were prepared with Orthic Luvisol soil formed from loamy sand and Haplic Luvisol soil formed from loess. Samples contained different doses of fertiliser in the range from 1 to 50 weight percent. Differences in water vapour sorption on Rosahumus (RH) as well as the soils were observed. The properties of soil mixtures and organic material depended on the properties of both components and on the dose of Rosahumus. However, fertiliser was a dominant factor in sorption processes of investigated mixtures. Adsorption isotherms obtained by gravimetric method belonged to the same type II, in accordance to the BET classification. Significantly higher influence on the water vapour sorption was associated with fertiliser dose and was greater for mixtures with soil formed from loess. The increase of water vapour sorption was visibly higher for mixtures below 4% of Rosahumus content. On the other hand, greater concentration of RH resulted in similar amount of water vapour sorption and for Rosahumus dose of 50% the sorption was practically the same. Similar results were found for the maximum hygroscopicity (Mh) of mixtures. Strong correlation was observed between the Mh and the amount of added organic fertiliser with determination coefficient (R2) from 0.997 to 0.998.
The penetration of bovine enterovirus, LCR - 4 strain deep into soil profiles in the field conditions was researched. Three soil types were selected: podzolic soil, black earth and browned black earth. The soils differed considerably in respect to their physical properties and chemical analysis. The best conditions for drainage were observed in podzolic soil, whereas the worst - in browned black earth. Experimental plots were being sprinkled with the 1:1 mixture of bovine enterovirus (at the concen-tration of 1x106.0 TCID50/1 ml) and slurry. The enterovirus researched, in any soil, migrated to the depth of 7.5 to 10 cm. The highest titres were observed in the surface layers of black earth and podzolic soil (0-2.5 cm). They differed from 102.72 - 104.27 TCID50/g of the soil. With depth the titres decreased, with slight fluctuations observed.
Bh horizons of Podzols formed from regoliths of sandstones, granites and gneisses in the Sudety Mountains are dark in colour, rich in organic substance, strongly acidic and slightly saturated with basic cations. They are also significantly enriched with organic and amorphous compounds of iron and aluminium. They meet all the morphological and physicochemical requirements of illuvial spodichorizons. Despite the evidence of lithological stratification of slope covers and possible polygenesis of B horizons, it is justifiable to classify these soils as Podzols, as adequately describing their morphology, basic properties and tendencies for present development.
The aim of the paper is to characterize some aspects of site conditions in selected places with the occurrence of heather (Calluna vulgaris) within the certain area of the Toruń Basin affected by military activities. Relations of heathlands to the soil cover appear to focus on the position of heather in the ecological succession on presently developing, young sandy soils and regularities of the heather distribution in a mosaic with grasslands in isolated dune fields. Studies were performed at two sites: Stawki and Chorągiewka.Heathlands of this area are connected with nutrient-poor and dry sandy habitats. In the ecological succession, which proceeds in places previously devoid of the vegetation cover and strongly deflated, they occur as a transitional type of vegetation, displacing plants of initial psammophilous community (Spergulo-Corynephoretum) and later giving place to pine forest. In the soil evolution, they are connected with the intermediate stage represented by arenosols (haplic arenosols) - weakly developed but sufficiently acid soils. On deforested, parallel dunes of the Toruń Valley, there are specific regular mosaics of vegetation and soil. Heather occurs on podzolized soils (albic arenosols, haplic podzols) on north-western slopes. Dry grasslands (Calamagrostis epigejos) cover slopes with south-eastern exposition, with soils eroded down to bed-rock and now regenerating to the stage of arenosols (haplic arenosols). Podzolized soils seem not to be developed under heather but rather under the relics of former pine forests preserved from erosion and deflation on less steep and more moist slopes.
The study was conducted on podzolic soil from a field fertilised with municipal-industrial sewage sludge at the following doses – 30 (1%), 75 (2.5%), 150 (5%), 300 (10%) and 600 Mg ha⁻¹ (20%) – and then planted with basket willow (Salix viminalisL.). In the 4th, 5th and 9th years of maintaining the plantation, the following determinations were made in the soil: numbers of lipolytic bacteria and fungi, and lipase activity. It was demonstrated that in the 4th and 9th years of the study, for most of the experimental treatments, there was still continued stimulation of the growth of lipolytic bacteria and fungi in soils from the 0-20 cm layer. In that soil layer for all the years of the study there was a distinct stimulation of lipase activity. The positive effect of the sludge on the numbers and activity of the above microbial groups was also observed in soils from the 20-40 cm layer, but only for some of the experimental treatments.
The aim of these studies was to assess the impact of genetic horizons of podzolic soil and eutric cambisol on the yield and chemical composition of ryegrass. In plants the same components were quantified as in soil in an exchangeable form. What was additionally quantified in plants was the total nitrogen and the content of organic acids, as they make it possible to determine the ionic balance.
The present study compares properties of podzolic soils developed from sandy materials overgrown by forests, affected either by alkalizing or acidifying emissions. The study entailed sampling 4 pedons in the vicinity of the Ożarów Cement Plant S.A. and 4 pedons near Rudniki village (within the impact zone of “Osiek” Sulphur Mine and Połaniec Power Plant). Soil samples were analyzed for basic chemicalproperties. The study showed significant changes in physicochemical properties of the alkalized podzolic soils: an increase in pH value, in base saturation of the exchange complex, contents of plant available potassium and magnesium, CaCO₃ content in organic and humic horizons and in salinity, and a decrease in organic carbon content and hydrolytic acidity, podzolic soils occurring in areas affected by anthropogenic acidification were characterized by decreased pH value, increased total sulphur and sulfate (S-SO₄) contents, increased hydrolytic and exchangeable acidity, and lowered base saturation of the exchange complex.
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