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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.
The objective of this study was quality estimation of air-dry and water-stable soil aggregate distribution in Polish Haplic Chernozems developed from loess. It was found that among the Chernozems classified in the particular complexes of agricultural suitability there were small differences in the content of air-dry aggregates with sizes of 0.25-10 mm. The distribution of air-dry aggregates in horizons Ap, A, and ABw was estimated as good or medium, while that in horizons Bw and Ck as medium or poor. In the Chernozems classified in the very good wheat complex and the good wheat complex the content of water-stable aggregates with sizes of 0.25-10 mm was significantly greater than in soils classified in the deficient wheat complex. The water-stable aggregate distribution in the Ap horizons of soils classified in the very good and good wheat complexes was estimated as good, and in the Ap horizons of soils of the deficient wheat complex as medium. In horizons A the distribution of water stable aggregates was assessed as medium, and in horizons ABw, Bw, and Ck as poor or very poor.
Five profiles of chernozems from several European countries were examined in the present study. The chernozems developed from various rocks and differed in their morphology and chemical properties. Mineralogical studies were carried out on the fraction <2 ľm by an X-ray method, using a diffractometer with a proportional recorder. It was found that all European chernozems examined in this study had a similar mineral complex of the clay fraction. Its major components were montmorillonite and illite usually forming mixed structures, whereas kaolinite, quartz, vermiculite and chlorite were present in smaller amounts, and feldspars occurred as trace minerals. Basically, differences in the mineral composition of various profiles and various soil horizons lie in different quantitative relations between the minerals listed above.
The aim of the present research work was to evaluate the influence of lithogenic conditions on the physico-chemical properties, quantity and quality of humus components in the black earths from the Małopolska Upland. Soil samples were collected from 5 soil profiles which represented proper black earth (profiles No. 1-4) and degraded black earth (profile No. 5). All the investigated soils were under sward. The examined black earths were characterised by different physico-chemical properties strongly related to the parent rock type. Their pH level and sorption capability were decreasing with a decrease in the clay content of the soil texture. Humus resources were the lowest in sandy black earths (average 212 t ha-1) and the highest in the black earh derived from clay (454 t ha1). In the humus composition of the examined black earths, humic acids dominated over fulvic acids. In the A horizons, the Ch:Cf ratio was close to 1, and lower in the upper parts of these horizons which is typical of turf soils. Humus horizons in some of the investigated black earths were classified as epipedon anthropoid according to phosphorus content soluble in 1% citric acid (109 P kg-1 soil).
The study of the bovine enterovirus survival in water, slurry, and two layers of black soil, was carried out at 4°C and 20°C under laboratory conditions. Samples of soil, water, and slurry were infected with a suspension of the enterovirus. The titre of the virus at 4°C was determined on the day of inoculation (day 0) and on 7, 21, 42, 70, and 135 d after inoculation. At 20°C, the titre was determined at day 0 and after 7, 21, 35, and 49 d. The study showed that bovine enterovirus, present particularly in the samples of water and slurry, retains its ability to cause cytopathic effects. The temperature of 20°C significantly shortened the survival of the virus in water, soil, and slurry. The process of virus inactivation in the soil proceeded faster than in slurry and water, which indicates that viruses in the soil are subjected to the action of different factors.
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