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Damian Stefaniuk, Adrian Różański and Dariusz Łydżba

Abstract

In this work, the complex microstructure of the soil solid, at the microscale, is modeled by prescribing the spatial variability of thermal conductivity coefficient to distinct soil separates. We postulate that the variation of thermal conductivity coefficient of each soil separate can be characterized by some probability density functions: fCl(λ), fSi(λ), fSa(λ), for clay, silt and sand separates, respectively. The main goal of the work is to recover/identify these functions with the use of back analysis based on both computational micromechanics and simulated annealing approaches. In other words, the following inverse problem is solved: given the measured overall thermal conductivities of composite soil find the probability density function f(λ) for each soil separate. For that purpose, measured thermal conductivities of 32 soils (of various fabric compositions) at saturation are used. Recovered functions f(λ) are then applied to the computational micromechanics approach; predicted conductivities are in a good agreement with laboratory results.

Open access

Przemysław Bobrowski, Maciej Jórdeczka, Michał Kobusiewicz, Marek Chłodnicki and Kusiak Jarosław

Abstract

Today’s desert area of Red Sea Hills is now inhabited by a Beja-Bisharin tribe, the camel breeders. In prehistoric times, this area was inhabited or penetrated by pastoral communities engaged in cattle breeding. Their occupation is primarily marked by thousands of engravings with representations of long-horned cattle, which were discovered in a rock art gallery in Bir Nurayet, one of the largest rock art galleries in Africa and the whole world. We still do not know when the shepherds and their herds abandoned the area. This issue can be addressed by geoarchaeology and investigation of sediments discovered in Wadi Diib, i.e. silts. As we believe, they record climate and environmental changes taking place in recent millennia, which probably to a large extent determined the socio-cultural processes in the area.

Open access

Krzysztof Pabis and Magdalena Błażewicz-paszkowycz

Distribution and diversity of cumacean assemblages in Admiralty Bay, King George Island

Eleven species of cumaceans were found in 105 samples collected in Admiralty Bay (King George Island) in the summers of 1984/85 and 1985/86, from 20 to 500 m depth range. Four cumacean assemblages were distinguished using the multivariate analysis. They were characterized by the dominance of one or two species often with low density values. Two assemblages were found in open waters of Admiralty Bay. The first inhabited on sandy-clay-silt and silty-clay-sand bottom deposits in the depth range from 140 to 330 m, with Campylaspis maculata (1.6 ± 2.1 ind./0.1m2; F = 72.4%) and Leucon sp. (1.4 ± 1.6 ind./0.1m2; F = 68.9%) as key species. The second assemblage was found in the depth range from 50 to 120 m with silty-sand sediments, and it was characterized by the presence of Vauthompsonia inermis (6.5 ± 6.6 ind./0.1m2; F = 92.0%). A third assemblage was found in shallow waters influenced by glaciers in the bottom area of Ezcurra Inlet. It was characterized by sandy-clay-silt sediments and the presence of Eudorella splendida (14.6 ± 9.4 ind./0.1m2; F = 100.0%) as a core species. The last assemblage was found in the shallow sublittoral (50-100 m) of Ezcurra Inlet and the central basin, with Diastylis anderssoni armata (1.5 ± 1.1 ind./0.1m2; F = 85.7%) and Diastylopsis goekei (1.1 ± 1.0 ind./0.1m2; F = 71.4%) as the most frequent and abundant species. V. inermis is considered a eurytopic species with high frequency in the whole material, and was present in all four distinguished assemblages. E. splendida and D. goekei were also recorded in each of the assemblages, but their total frequency was lower.

Open access

Dariusz Błażejczak and Jan B. Dawidowski

Abstract

The objective of the paper was to verify the previously obtained results of research concerning the impact of the plate diameter on the measured value of the pre-compaction stress of silt (NG), in conditions of a wider range of soil types and their initial stage. The research was carried out on samples with a diameter of 100 mm and height of 30 mm produced from the soil material (M) or collected from the subsoil of the selected soils (AWN) with the granulation type of: silt loam, loam, light loam, sandy-clay soil. The following soils properties were determined: the granulation type, density of the solid phase, content of humus and calcium carbonate, reaction, plastic and liquid limit. The properties of samples were described with moisture, dry density of solid particles, porosity of aeration, degree of plasticity and degree of saturation. The samples were loaded with a testing machine with plates with varied diameters. The value of the pre-compaction stress of soil was measured with the method of searching the crossing point of tangents with the secondary stress curve and the original stresses curve (a classical method). It was found out that for samples M with the degree of saturation of 0.40-0.50, the pre-compaction stress does not significantly depend on the plate diameter. For samples M or AWN, with the degree of saturation of 0.64-0.82, the pre-compaction stress significantly depends on the diameter of the plate. A conclusion was formulated that in the research of NG with the method of uniaxial defonnations, the relation of the diameter of the plate (d) to the diameter of the cylinder (D) should be within 0.5 ≤ d/D ≤ 0.8.

Open access

Suzana Mirela Puflea and Ion Ioniţă

Abstract

Located in the Central Moldavian Plateau, the Stavnic catchment is associated to a left tributary of the upper Barlad River, and extends on 21,341 ha of which 39% is under forest.

The typical hilly landforms, the alternation of permeable and impermeable rocks (clays, sands, loess-like deposits), the unrolling of wetted and dry periods, the sequence of freeze and thaw cycles, and the influence of the anthropogenic factor triggered the acceleration of land degradation processes. The present day geomorphic processes such as soil erosion, gullying, mass movements and silting of reservoirs represent a major threat to the local environment.

Soil erosion on the agricultural land covers mainly the land with slopes of over 5%, and it highlights through different stages of intensity. By data processing, gained from the soil surveys undertaken by O.J.S.P.A. Iasi and Vaslui, it is obviously that moderate-excessive soil erosion extends on 52% of the surveyed area.

The gully erosion apparently plays secondary role in the Stavnic catchment. However, there has been identified a total number of 330 gullies, most of them being included into discontinuous gullies class, often located on the hillslopes.

Landslides are the most representative geomorphologic processes and they extend on 12,006 ha, which represents 56% of the Stavnic catchment. One mention must be made, that in the context of climate aridisation occurred during the last three decades, the landslides are almost all stabilized. The majority of the few active landslides have frequently formed through the reactivation of the old landslide diluvia.

By using the Cesium-137 technique in dating the recent sediments from the Cazanesti accumulation, within the lower Stavnic catchment, the mean siltation rate of 4.5 cm yr-1 after the Chernobyl nuclear accident was estimated.

Open access

R. Saraswathy and Pitchai Kasinatha Pandian

Abstract

The Pulicat Lake is the second largest brackish water lake after Chilika Lake in India. The average area of the water spread is 461 sq km. During the monsoon Pulicat Lake receives freshwater through three major rivers, namely, the Swarnamukhi, the Kalangi and the Arani. The Pulicat lagoon system, which is a storehouse of rich biological resources, is under great threat because of the anthropogenic influences. The Pulicat Lake ecosystem is degraded by siltation, bar mouth dynamics, shell mining and processing and population pressure due to the resettlement of villagers from Sriharikota Island. It has been determined that the extent of the lake, including its water spread area, is decreasing. Therefore, it is essential to assess the land use / land cover changes taking place in and around Pulicat Lake using remote sensing and GIS. Studies on its sediment characteristics are also vital. The grain size content reveals that most of the sediments contain clay and silt in enormous amounts. This lake has been the prime source of a livelihood through fishing for a large section of the population living in the surrounding villages. It is the most important refuge for water birds in south India. The fishing community who lives in and around Pulicat Lake follows the Padu system for fishing in the lake. In this study, apart from studies on configuration changes and sediment analysis, a study of the flora and fauna of the lake and the socio-economic conditions of the local community were also carried out. Finally, mitigation measures for the sustainable protection of the lake’s ecosystem were identified.

Open access

Michał Stępień, Elżbieta Bodecka, Dariusz Gozdowski, Magdalena Wijata, Joanna Groszyk, Marcin Studnicki, Grzegorz Sobczyński, Jan Rozbicki and Stanisław Samborski

Abstract

Two groups of soil texture classification, differing in limit diameters for particular soil fractions, are used in Poland. The older groups of classifications consider soil particles as < 1 mm and divide them into sand (1.0–0.1 mm), silt (0.1–0.02 mm) and fine or flowable particles (< 0.02 mm). These classifications are used, in a version which originated in 1956 and here denominated as PTG/Musierowicz 1956 in land quality assessment and elaboration of soil agricultural maps. Newer versions of these classifications – professional standard BN-78/9180-11 (1978) and division of soils in agronomic categories described in 1986 – are used in fertilizer recommendations and in agricultural drought monitoring. According to the new soil texture classification PTG 2008, the upper diameter limit for soil particles is 2 mm and these parts are divided into sand (2.0–0.05 mm), silt (0.05–0.002 mm) and clay (<0.002 mm). This classification is compatible with soil texture classification elaborated by the United States Department of Agriculture (USDA) and most frequently applied worldwide. In this paper, the results of analyses of 1087 soil samples representing almost all granulometric groups existing in older and newer Polish soil texture classifications were considered. On the base of the current and earlier studies, the table with probability of occurrence of granulometric group PTG 2008 or texture class USDA for particular granulometric groups BN-78/9180-11 was prepared. For majority of granulometric groups (pl, ps, psp, pgl, pgmp, gp, gpp, gl, glp, gc, gcp, ip, płi) determined on the base of BN-78/9180-11, it is possible to determine their granulometric group/texture class according to PTG 2008/USDA correctly and, frequently, unambiguously. For granulometric groups pglp, pgm, gs, gsp i and płg it is possible to propose with great probability more than one equivalent according to PTG 2008/USDA, and in other cases more studies are recommended.

Open access

Beata Klojzy-Karczmarczyk, Janusz Mazurek and Krzysztof Paw

Abstract

In recent years, the economic importance of gangue mined during coal production has changed and it is currently treated more and more often not as waste but as a source of mineral resources for economic use. The overriding objective throughout the reclamation process of open-pit mines associated with the utilization of external material is to make sure that the placement of waste rock on the surface does not cause damage to the environment. The paper presents results of the diagnosis and evaluation of the possibility of filling open-pit mine workings with mining waste or other materials, for example aggregates produced on the basis of gangue, originating in the Janina Mine mining plant (a subsidiary of TAURON Wydobycie S.A.). The study involved aggregate or coal silts from dewatering on the filter presses. The evaluation refers to the legal aspects and takes the requirements of pollution prevention into account, with a particular emphasis on soil, surface water and groundwater. The analysis of the potential impact on the soil and water environment of the project involving reclamation of the open-pit excavation with the use of minerals or waste from coal mining was carried out based on a study of the total content of sulfur and other elements in the samples pierwiastków (As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, V and Zn), as well as of the leaching of components. Moreover, an examination of the coefficient of permeability and porosity was conducted, which allowed the suitability of the material for the construction of insulating layers to be determined. The physical and chemical analyses were conducted on a total of over a dozen samples of waste rock, a byproduct of the enrichment of coal in the Janina Mine plant. The specific studies of the total sulfur content were conducted for the 16 primary samples scattered into 15 fractions each. Moreover, the so-called secondary samples were created, meaning that fine fractions of less than 20 mm and less than 10 mm were rejected. The total content of the selected components was examined for such crafted samples and their concentrations were determined in the leachable form (batch test 1:10). In the case of use of waste rock as an aggregate for quarry reclamation, a comparative analysis was applied to the legal requirements assigned to the mining waste and the quality of soil and water environment. Based on the conducted studies, it has been concluded that the coal silts (filter cakes) are characterized by good insulating properties and can be used for waterproofing objects, especially in the industrial, communications and mining areas. However, coal silts do not meet the quality requirements, mainly due to their slightly increased chlorides content, in addition to being a waste, which in some cases limits the possibility of their use. The best quality parameters were found for the gangue from the Janina Mine (on the basis of which aggregates are manufactured), but deprived of fine fractions. Physical and chemical analyses of the total content of elements in the secondary samples showed that the obtained values are within the allowable ranges determined by appropriate regulations for the vast majority of samples. The limit of 1% was assumed for the sulfur content. The conducted research on the leaching of pollutants indicates that the tested samples do not introduce contaminants exceeding the limit values for the analyzed metals and sulfates. Only single exceedances of the analyzed parameters are observed. The test results allow to conclude that it is possible to obtain a useful product that meets the requirements of environmental protection, but only after the rejection of fine fractions of the waste material.

Open access

Joanna Mirosław-Grabowska

ABSTRACT

The results of isotopic investigations of the Skaliska Basin sediments are presented. Stable isotope analyses were done for authigenic carbonates from three profiles: W1 - Piotrowo-Ławniki, W2 - Sąkieły Małe, and W4 - Budzewo. The profiles contain carbonate silts at the bottom, then calcareous detritus gyttja and organic silts and peat at the top. Palynological data indicate that sediment were accumulated in the Skaliska Basin from the final phase of the Younger Dryas to the Subboreal period. The values δ18O change from ca −9.4 to −4.5‰, and δ13C values varies from −5.1 to +0.1‰. Such a large range of isotopic data reflects changing conditions in the basin during accumulation of deposits (different water levels, water temperatures, and bioproduction). Based on the results of stable isotope analyses of the carbonates, isotopic zones (Is) were defined and characterized for each profile. The results of isotopic analysis enabled reconstruction of varying environmental conditions connected with lake deepening and/or influx of water enriched in light isotopes, climatic warming, and increase of biological activity. The Late Glacial deposits are characterized by δ18O values of ca −6.5-6‰ and δ13C of ca −1‰. In the transitional time between the Late Glacial and the Holocene, δ18O systematically falls below −8‰, reflecting a substantial change in the isotopic composition of the lake water, likely caused by to inflow of melt water. During the Preboreal period the δ18O as well as the δ13C values systematically decrease and reach minima (−8.4-9.4‰ for δ18O and ca −3.5-4.7‰ for δ13C). At the beginning of the Boreal period, an increase of ca 2‰ in δ18O is noted and is associated with climatic warming. During the Atlantic period the varying trends in the δ18O record are likely connected with changing precipitation/evaporation ratios, causing changes in the isotope composition of the water. The fluctuations of the isotopic values in the upper parts of the successions probably point to shallowing of the lake due to sedimentary infill.

Open access

Łukasz Bąk and Szczepan Ludwik Dąbkowski

: Strategies for Monitoring, Prediction and Control. Eds F. Hadley, Mizuyama. IAHS Publ. 217. Wallingford, IAHS Press, p. 101-108. http://iahs.info/redooks/a217/iahs_217_0101.pdf BATUCA G. D., JORDAAN M. J. 2000. Silting and desilting of reservoirs. Rotterdam, Netherlands. A.A. Balkema. ISBN 9789054104773 pp. 353. BĄK Ł., DĄBKOWSKI SZ. L., GÓRSKI J. 2011. Metoda prognozowania zamulenia zbiornika wodnego na podstawie pomiaru pojemności [Method of predicting siltation of a water reservoir based on measurements of its capacity]. Woda