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The paper presents the results of measurements of shrinkage characteristic for alluvial clay soils from the Delta of Vistula River. Measurements were conducted on undisturbed soil aggregates using ‘so-called’ saran resin method. Five following shrinkage characteristic models were fitted to measured data: four segment analytical model, combined exponential-linear model, general soil volume changes equation, three straight lines model and logistic model. The comparison of different models depending on coordinate system as well as advantages and disadvantages of various models are discussed.
The samples were taken from 7 profiles of alluvial soils formed from varied gytias on calcareous sinter. The research concerned determination of composition of exchangeable cations and basic saturation. In the analysed soils, lithologic discontinuities in the profile structure were observed. The calcareous sinter located in the lower part of the profile caused characteristic water properties and occurrence of gleyic process. The investigated soil profiles were varied in their morphological structure and physicochemical properties. Fluctuations in the content of carbonates, organic mater and non-carbonate mineral substance confirmed the existence of several cycles in the formation of these soils. The basic saturation (S) of the analysed soils ranged between 287.4 and 2238.7 mmol(+) kg–1. The highest values were detected in gytia horizons (gyd), and the lowest ones - in gleyic horizons (G). The dominant cation in sorption complex of all horizons was calcium, and its highly differentiated content ranged from 245.3 to 2089.6 mmol(+) kg–1. Magnesium was the second most abundant cation in sorption complex. The content of Mg2+ ranged from 19.4 mmol(+) kg–1 in clay-lime gytia horizons to 143.5 mmol(+) kg–1 in lime gytia horizons. The lowest in the content among exchangeable cations in the analysed samples was potassium (0.6-12.9 mmol(+) kg–1). Our comparison of the divalent cation content (Ca2+, Mg2+) and monovalent cation content (Na+, K+) showed significant instability of the balance between these groups of cations, which was confirmed by a very wide range of the ratio (21.3-333.1) calculated between these two groups of cations. The amount of alkaline cations in the analysed soilsfollowed this order: Ca2+ > Mg 2+ > Na+ > K+ .
The average concentration of titanium in the alluvial soils of central Vistula was: 0.29% (ranging from 0.05-0.49) and from the Żuławy area 0.42% (ranging from 0.29-0.50), while in the clay fraction of all soils was: 0.43% (ranging from 0.29-0.49), respectively. The investigated soils contain natural amounts of titanium which can be accepted as a geochemical background. The element content correlates with the amount of particles < 0.02 and < 0.002 mm, Corg and Fe. Titanium showed little mobility in the gley soil-forming process andthebioaccumulation of the element in the humus horizons was not observed.
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Przewodnictwo wodne mad Polski

72%
W pracy przedstawiono wyniki badań dotyczących opisu zmienności współczynnika przewodnictwa wodnego mad Polski. Stwierdzono, że najwyższymi wartościami współczynnika przewodnictwa wodnego charakteryzowały się warstwy powierzchniowa i podpowierzchniowa mad lekkich i bardzo lekkich w zakresie pF 0-pF 1,5, a najniższe wartości współczynnika odnotowano dla nich w zakresie pF 3-pF 4,2. Mady średnie i ciężkie oraz mady lekkie i średnie we wszystkich warstwach wykazały zbliżony charakter przebiegu wartości współczynnika przewodnictwa wodnego.
The aim of the study was to examine the physical and water retention properties of the Holocene alluvial and deluvial soils in the morainic, riverine and delta landscapes of north-eastern Poland. In comparison to eroded soils, deluvial soils in a morainic landscape featured lower compaction, higher retention capacity corresponding to field capacity, higher values of potentialuse ful retention (PRU) and water easily available for plants (ERU). Deluvial soils in the landscape of morainic hills and plains, despite the statistically significantly higher field capacity in relation to deluvial soils in the lakeland hill landscape, had similar amounts of useful retention and water easily available for plants. The highest value of soil water potential at 98.1 hPa (pF 2.0), 490.5 hPa (pF 2.7), 981.0 hPa (pF 3.0) and 15 547.9 hPa (pF 4.2) was found for alluvial soils in riverine landscapes. These soils, despite the high water capacity, had similar amounts of water available for plants (PRU) in comparison to alluvial soils in delta landscape and deluvial soils. The most favourable water-air properties were found for the deluvial soils in lakeland hill landscape. The ratio of mesopores to macropores and to micropores amounted to 1:1.32:1.24.
Quite large areas of the alluvial soils in the valley of the river Bobr were destructed by the sand and gravel exploitation. After the recultivation measures, which consisted of backfilling of the open-castwith waste aggregate, levelling the surface and putting on such prepared surface 50-200 cm of the stripping material,the yield was very low.The field and laboratory experiments have shown that during the technical operations the soil was compacted to such degree, that the root growth and water permeability was restricted to large extent.The soil compaction was noted in the whole soil profile.The evidences of this process were the high bulk density( often over 1,8 Mg m-3), very low water permeability values and low air capacity. The situation during the 12 years from the finishing of the recultivation has not changed.
Alluvial soils of the Vistula River delta are one of the most fertile soils in Poland. Part of the area is a depression, whose agricultural utilization relies upon the efficient reclamation systems on polders. High ground water levels enhance redox processes, restriction of which is one of more important functions of the draining systems. This paper presents short characteristics of the redox status of alluvial soils in the delta and describes processes and consequences of oxygen deficits in soils. The importance of indices of oxygen deficit for the formation of water conditions, which would favour agricultural utilization of the delta soils, is underlined.
In June 1994 samples of soils and meadow plants were collected at 21 spots situated along the left bank of the Vistula within the Cracow province boundaries (Fig. 1). Two soil samples and one sample of meadow plants were picked between the embankment and the river-bed, as well as outside the flood bank al each spot. In all samples the contents of Cd, Cu, Ni, Pb and Zn were determined and also the basic physico-chemical properties of the soils. Turf soils in the Vistula valley within the Cracow province are highly diversified as to their basic properties and heavy metal contents (Tab. 1, Fig. 1 and 2). The highest accumulation of heavy metals and diversification in their contents are observed in the top layers of soils in the valley bottom zone adjoining the river-bed, separated by the flood bank. Total heavy metals contents range from 0.42 to 84.04 mg Cd, 87-2120 mg Zn, 7.5-181.4 mg Cu, 16.4-217.7 mg Pb and 15.4-60.7 mg Ni/kg d.m. Except for nickel, the level of examined heavy metals concentration in a majority of soil samples from this zone is described as serious or dangerous contamination (Tab. 3). Average content of investigated metals in the soils outside the embankment approximate to the contents most commonly noted in I tic arable lands in Cracov province. The contents of cadmium, zinc and copper in the soils within the embankment in the lower regions of the Vistula below Cracow are on an average ca 2 times higher that in the upper region. An analogous raise in lead concentration is almost 1.7 times higher. Only nickel contents in the soils of these two regions are almost identical. Nearly all samples of meadow plants from the zone between the flood bank and river-bed and many picked outside the embankment contained excessive amounts of cadmium from the point of view of their fodder usability (Tab. 4).
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Retencja wodna mad Polski

58%
W pracy przedstawiono charakterystyki potencjał wody glebowej-wilgotność mad Polski. Stwierdzono, że największe ilości wody retencjonowane są w madach średnich i ciężkich oraz, madach lekkich i średnich, a najkorzystniejsze stosunki wodno-powietrzne panują w madach lekkich i średnich.
Przeprowadzono badania wpływu intensywności użytkowania rolniczego na zawartość wybranych mikroskładników w glebie: Cr, Cu, Ni, Pb i Zn. Obserwacjami objęto cztery typologicznie różne gleby wytworzone z pyłu: czarnoziem, płową, płową niecałkowitą i madę rzeczną. Na każdej z badanych gleb wyznaczono po pięć obiektów użytkowych: sad, chmielnik, pole, użytek zielony i las. Próbki glebowe pobierano z dwóch warstw z poziomów akumulacyjnych (Ap i Ah): 0 - 10 cm i 10 - 20 cm, oraz z głębokości poniżej 35 cm (z poziomów Bt i Ah). Oznaczono całkowitą zawartość mikroskładników w glebie (IPC-AES). We wszystkich glebach użytkowanych rolniczo stwierdzono podwyższoną zawartość badanych metali ciężkich, szczególnie na obszarach użytkowanych najbardziej intensywnie. Znaczące przekroczenie norm zasobności gleb w metale ciężkie, nastąpiło jedynie w dwóch przypadkach. Oba obiekty położone były na madzie a przekroczenia te stwierdzono w warstwie 0 - 10 cm (chmielnik - 138,5 mg Cu·kg⁻¹; sad - 144,0 mg Zn·kg⁻¹).
The alluvial soils in the Bóbr river valley, devastated by sand and gravel exploitation, were reclaimed for agricultural use. After reclamation treatment, the newly formed soil was very acid. Application of 5 Mg/ha lime elevated soil pH to 6-7, but during the following years, soil pH dropped again by about one half of the pH unit a year. Rapid drop in the pH level can result both from geological and soil-forming processes. Efficiency of mineral fertilizers applied in various combinations did not give the expected results and the yield of cultivated plants was not satisfactory. Mineral fertilization in various combinations did not result in the expected yield levels.
Obtained Embankments of the Mała Wisła River are a typical example of "old", exploited for several dozen years flood embankments made of local soils taken up in a close vicinity of the constructed bank and the river. The soils were alluvial soils i.e. cohesive soils containing organic parts according to the geotechnical classification. Along a section of the Mała Wisła from its confluence with the Biała River to the outflow of the Przemsza a flood in July 1997 posed a threat to the security of areas protected by flood embankments. Water level between the banks sometimes reached the crest's ordinate; local seepage and water flow through the body and substrate of the banks were observed. Soon after the flood, a technical evaluation of the embankments involved all four sections of a combined length of c. 7.6 km, where these phenomena were recorded. The paper discusses results of this evaluation, which concluded that the studied embankments did not meet technical standards and requirements, which should be fulfilled by the flood banks. Their modernization along the whole stretch was found to be necessary.Conclusions drawn from detailed studies carried on the embankments of the Mała Wisła may be valid for most flood embankments in Poland.
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