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The Mg content in individual granulometric fractions of the soils studied was found to be inversely proportional to the fraction diameter. The >0.02 mm diameter fraction separated from soils originating from loess were between 60 and 130%, richer in magnesium than the same fractions separated from Carpathian soils, at 80% on average. It has been found that the lower the content of a given granulometric fraction in the soil, the higher its share in the distribution of the total magnesium pool in the soil. Hence, in light soils with a low content of the <0.02 mm fraction, the share in the accumulation of the total Mg pool in the soil mass is considerably higher than in the case of similar fractions of heavy soils that are richer in the <0.02 mm fraction, and also in the colloidal fraction of <0.002 mm.
The research conducted shows that along with the decrease of the diameters of fractions, the total content of Mg increases and the leaching process of the soils investigated visibly decreases the content of this element in almost all fractions investigated. In addition, a considerably higher total content of Mg in the boulder loam than in old-alluvial sediment of the fractions was observed. In average separate fractions, the following amounts of total Mg accumulate: sand (1-0.1 mm) 5.6 to 7.3%, silt (0.1-0.02 mm) 7.3 to 13.3%, fractions of silt- clays (0.02-0.002 mm) 52.2 to 54.1% and clay fraction (<0.002 mm) 25.3 to 34.9%.
The content of the total potassium in particular granulometric fractions increases from a sand fraction (1-0.1 mm) to fine silty clay (0.002-0.005 mm), while in the clay fraction it usually decreases. The most diverse fractions in terms of potassium content are those extracted from mountain soils developed from old Cretaceous and Tertiary forms. Granulometric fractions extracted from soils developed from loessial sediments are homogenous with regard to the total potassium content. In those sediments there is a close parallelism between the amount of a given fraction in the soil and the amount of potassium contained in the fraction. This relation laid behind this attempt to calculate the coefficients for the total potassium content in soils on the basis of the granulometric analysis.
The content of the total calcium was studied in granulometric fractions of the following diameters: <0.002, 0.005-0.002, 0.02-0.005, 0.05-0.02, 0.1-0.05 and 1.0-0.1 mm. It was observed that the amount of Ca accumulated in particular fractions is not correlated with their content in soils. The ratios of Ca content in a given fraction to the content of the granulometric fraction (Ca/Fr) keep gradually decreasing from a clay fraction <0.002 to a sandy fraction of 0.1-1 mm. No calcium migration from the surface of the studied soils down the profile was observed in particular fractions, except for the clay fraction <0.002 mm in lessive soil profiles.
The material for this study was obtained from several regions of Poland, from 13 soil profiles of various geneses that include those formed from various rock types. It has been observed that the total aluminium content in the individual granulometric fractions increased as soil particle diameter decreased. Similarly, the share of individual fraction groups in the total aluminium accumulation in the soil mass increased as to particle diameter decreased. The <0.005 mm grains stored a greater share of the total aluminium than indicated by their share of the soil mass, whereas <0.02 mm grains had a smaller share of the aluminium than their share of the soil mass.
The studies were carried out on material representing 13 different soil profiles from various regions of Poland. The content of total iron in 6 granulometric fractions of soils derived from various parent material showed high variation. The most varied with respect to the content of iron are the clay fractions, and the least are silt and sand fractions. The richest in total iron are fractions occurring in smallest amounts, and the poorest are those which dominate in granulometric composition.
The content of total calcium in particular granulometric fractions is in most cases not correlated with particle size. In soil developed from boulder loam, total Ca content in the analyzed grain sizes increases with depth due to the presence of CaCO₃ below 100 cm. In turn, in soil developed from old-alluvial deposits, in which CaCO₃ was not noted, Ca content does not reveal any regularity in the particular fractions. The total calcium content in particular fractions depends on the leaching process and the origin and properties of the parent rock.
W pracy przeanalizowano zmiany składu granulometrycznego i zawartość materii organicznej w glebie, która uległa zmyciu z kolein w czasie 30 minutowego deszczowania. Erozję wodną gleby badano w koleinach utworzonych ciągnikiem oraz w koleinach pozostawionych przez ciągnik z przyczepą. Pomiary wykonano na glebie lekkiej w warunkach kontrolowanych przy użyciu symulowanego deszczu.
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