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Lucia Kořenková and Martin Urík

Abstract

Water repellency in soils is controlled by many different factors, basic physical and chemical properties might be considered the crucial ones. For the purpose of this study, 12 sites were selected and sampled (0–20 cm depth) in the White Carpathians. Repellency tests were conducted under laboratory conditions in triplicate using water drop penetration time (WDPT) test and the molarity of ethanol droplet (MED) test. Results of WDPT measurements showed that three samples were marked by slight to extreme water repellency. Regarding the relationship between WDPT/MED and tested soil properties, the highest value of correlation coefficient was calculated for soil organic carbon (r = 0.706; p < 0.05), suggesting there is a positive, statistically significant correlation between repellency severity and total carbon content. A negative relationship between repellency and soil reaction/silt/silt + clay contents of studied soils was found. Samples taken from the surface horizon of arable soils showed no repellency.

Open access

Barbara Sladonja, Marin Krapac, Dean Ban, Zoran Užila, Slavica Dudaš and Dušica Dorčić

Abstract

Pyrethrum (Tanacetum cinerariifolium (Trevir.) Sch. Bip.) is an autochthonous insecticidal plant from Dalmatia (Croatia). It is commercially grown worldwide with a particularly fast expansion in Africa and Australia (Tasmania) and used as a natural insecticide. The study was conducted in Istria, Croatia, in a greenhouse, to determine the effect of soil type on the germination of pyrethrum seeds. The effect of different soil types on the germination of pyrethrum was found to be highly significant. The highest percentage of germination was found on white clay loam (soil type 2), and the lowest on red clay Terra Rossa (soil types 1 and 6). Seed germination was greatly influenced by soil texture, foremost silt percentage, and soil pH. The present study suggests that pyrethrum seed germination is best on slightly alkaline clayey loams with moderate nutrients. Positive correlation was confirmed among germination percentage and silt content and soil pH.

Open access

Karolina Koś and Eugeniusz Zawisza

Abstract

Landfill liners from dam reservoir sediments. Every municipal solid waste landfill has to be properly secured to protect the natural environment from possible leachate. Most often an artificial sealing is used, which is based on a soil liner from cohesive soils (clays, silts). Usability evaluation of bottom sediments from Rzeszowski Reservoir for building these liners was presented in the paper. Sediments from dam reservoirs, gathered as a result of the siltation process, can be a valuable material for earthworks purposes. Determination of their possible ways of usage is important, especially before the planned dredging, because thanks to that this material will not be put on a heap. Based on the analysis of the geotechnical parameters of these sediments it was stated that this material can be preliminary allowed for using in liners.

Open access

Monika Niska and Anna Kołodziej

Abstract

This paper presents development of the paleolake Starowlany existing in the Eemian Interglacial (MIS 5e) in north - eastern Poland. The lake history is based on Cladocera analysis. The paleolake Starowlany is located in the central part of the Sokółka Hills, approximately 9 km north of the town of Sokółka in the North Podlasie Lowland. The sediments studied filled a southern part of a tunnel valley formed during the Warta Glaciation. The coring was carried out with a geological drilling and constituted a part of the frame work aimed at preparing the Sokółka sheet for the Detailed Geological Map of Poland in scale 1:50000. The core was 7 m long. Peaty silt, peats and organic silt were present at the depth of 4.0-6.6 m, under deluvial sands, tills and silt. Organic series was over lain by a clayey silt with no glacial cover. Cladocera analysis was conducted with 20 samples from a depth interval 6.6-4.1 m. Remains of 17 species of Cladocera were found, representing the families: Chydoridae, Sididae and Bosminidae. A vast majority of them were the littoral species. In the paleolake Starowlany four development zones were distinguished that reflected changes as regards temperature, trophic levels and changes of water level in the lake. The paleolake existed from the early until the middle Eemian. The high est water level and the most favorable conditions for zooplankton development occurred in zones SCZ I and II. The highest trophic level took place in SCZ III (middle Eemian). In the late Eemian the water level dropped and the paleolake was transformed into a wetland. At certain points, the higher water level enabled existence of a few Cladocera species. The reasons for disappearance of the paleolake Starowlany included a local decrease in ground water levels as well as morphometric and geological characteristics of the lake.

Open access

S.E. Obalum, J. Oppong, C.A. Igwe, Y. Watanabe and M.E. Obi

Abstract

The spatial variability of some physicochemical properties of topsoils/subsoils under secondary forest, grassland fallow, and bare-soil fallow of three locations was evaluated. The data were analyzed and described using classical statistical parameters. Based on the coefficient of variation, bulk density, total porosity, 60-cm-tension moisture content, and soil pH were of low variability. Coarse and fine sand were of moderate variability. Highly variable soil properties included silt, clay, macroporosity, saturated hydraulic conductivity, organic matter concentration, and cation exchange capacity. Overall, soil pH and silt varied the least and the most, respectively. Relative weighting showed that location dominantly influenced the soil variability, except for soil porosity and organic matter concentration influenced mostly by land use. Most of the soil data were normally distributed; others were positively skewed and/or kurtotic. The minimum number of samples (at 25 samples ha-1) required to estimate mean values of soil properties was highly soil property-specific, ranging from 1 (topsoil pH-H2O) to 246 (topsoil silt). Cation exchange capacity of subsoils related fairly strongly with cation exchange capacity of topsoils (R2 = 0.63). Spatial variability data can be used to extrapolate dynamic soil properties across a derived-savanna landscape.

Open access

Mirosław Orzechowski, Sławomir Smó;lczyński, Jacek Długosz and Paweł Pozniak

Abstract

The aim of the research was to compare the results of texture analyses of glaciolimnic sediments deposited in the basins of ice-dammed lakes origin in north eastern Poland. The study was carried out using aerometric method, pipette method and laser diffraction method. The studied soils were classified as Haplic and Mollic Vertisol, Vertic Cambisol, and Gleyic Chernozem. The soils were formed from clayey (clay, heavy clay), loamy (loam, clay loam, sand clay loam) and silty (silt loam, clay loam) deposits. The studied soils did not contain fractions > 2.0 mm. The amounts of clay fraction (< 0.002 mm) measured by areometric and pipette methods were similar and strongly correlated. In comparison to laser diffraction method, these amounts were 3-4-fold higher. The sub-fraction of fine silt (0.02-0.002 mm) predominated in soil formations analyzed by laser diffraction method. In comparison to areometric or pipette method, the amounts of fine silt were 2-4 fold higher. Basing on the calculated sedimentological indices, it was stated that the examined soils were well sorted and the mean grain diameter (GSS) was very low and did not exceed 0.005 mm in areometric and pipette methods, and 0.011 mm in laser diffraction method for clay sediments.

Open access

Zbigniew Młynarek, Katarzyna Stefaniak and Jędrzej Wierzbicki

Abstract

The article concentrates on the identification of geotechnical parameters of alluvial soil represented by silts found near Poznan and Elblag. Strength and deformation parameters of the subsoil tested were identified by the CPTU (static penetration) and SDMT (dilatometric) methods, as well as by the vane test (VT). Geotechnical parameters of the subsoil were analysed with a view to using the soil as an earth construction material and as a foundation for buildings constructed on the grounds tested. The article includes an analysis of the overconsolidation process of the soil tested and a formula for the identification of the overconsolidation ratio OCR. Equation 9 reflects the relation between the undrained shear strength and plasticity of the silts analyzed and the OCR value. The analysis resulted in the determination of the Nkt coefficient, which might be used to identify the undrained shear strength of both sediments tested. On the basis of a detailed analysis of changes in terms of the constrained oedometric modulus M0, the relations between the said modulus, the liquidity index and the OCR value were identified. Mayne’s formula (1995) was used to determine the M0 modulus from the CPTU test. The usefullness of the sediments found near Poznan as an earth construction material was analysed after their structure had been destroyed and compacted with a Proctor apparatus. In cases of samples characterised by different water content and soil particle density, the analysis of changes in terms of cohesion and the internal friction angle proved that these parameters are influenced by the soil phase composition (Fig. 18 and 19). On the basis of the tests, it was concluded that the most desirable shear strength parameters are achieved when the silt is compacted below the optimum water content.

Open access

Michał Ćwiąkała, Andrzej Greinert, Jakub Kostecki and Leszek Rafalski

Abstract

Using the alkaline fly ash after combustion of lignite as the acid soils neutralizer is a technique known for decades. Due to many disadvantages of the direct fly ash application it is sought to modify this material prior to its use. The process of fly ash modification in the magnetic activator involved breaking up fly ash to small grain sizes in order to obtain a material with a very large specific surface and modified properties. The purpose of the research was to compare the properties of unmodified fly ash with those of ash modified in the magnetic activator in terms of its usefulness in the neutralization of acidic soils. Unmodified fly ash was classified as a medium-grained calciferous material. The basic components of ash were silicates (33.28% of SiO2) and calcium compounds (31.26% of CaO). It has a low heavy metal content falling within a range characteristic of coal ash and meeting soil quality standard requirements. As a result of activation, the following changes were obtained in the properties of modified ash compared with unmodified ash: sand fraction content – reduced to 0.40, silt fraction content – increased by 1.40, silt fraction content – increased by 1.68, content of the sum of the dust and silt fractions – increased by 1.49, specific surface – increased by 1.65, fineness – reduced by 0.48. Modification of fly ash in the magnetic activator was found to have improved the physical properties of ash as acidic soil neutralizer, and its chemical properties make such an application possible.

Open access

Juris Burlakovs, Raimonds Kasparinskis and Maris Klavins

Abstract

Development of soil and groundwater remediation technologies is a matter of great importance to eliminate historically and currently contaminated sites. Stabilization/solidification (S/S) refers to binding of waste contaminants to a more chemically stable form and thus diminishing leaching of contamination. It can be performed using cement with or without additives in order to stabilize and solidify soil with the contamination in matrix. A series of experiments were done to determine leaching properties of spiked soils of different texture bound with cement. Results of experiments showed, that soil texture (content of sand, silt and clay particles) affects the leaching of heavy metals from stabilized soils.

Open access

Jan Jaremski

Abstract

Application of the pile joining is a new solution of the complex pile foundation including the base, made in the ground, and the piles joining the base with the girt. This kind of piles can be used for foundation under special geological conditions (proglacial stream valleys) for foundation reinforcement of the existing buildings and new foundations. The solution proposed may be used in the swelling soils. In this work, the possibilities of applying joining piles in different soils, like fine sands, silts, clays, clay shale, sandstones, which can be the foundation for the pales have been considered.