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What Determines Ion Content of Lumbricid Casts : Soil Type, Species, or Ecological Group?

Babiy Kirill A., Kniazev Stanislav Yu., Golovanova Elena V., Solomatin Denis V., Bel'skaya Lyudmila V.

Polish Journal of Ecology

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2021

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Vol. 69, nr 2

96--110

EN

Most soils possess a large supply of nutrients, but these reserves cannot be mobilized by plants, as they exist in a bound form. Therefore, it is need to understand mechanisms that naturally increase the acquisition of nutrients by plants. Earthworms are crucial soil engineers that play a key role in soil functioning. In this study we have estimated the impact of three factors, earthworm species, ecological group, and soil type, on the ion content of casts of Eisenia nordenskioldi, E. ventripapillata, E. nana, Lumbricus rubellus, and Aporrectodea caliginosa. Laboratory experiments were performed in microcosms on three soil types. We analyzed five water-soluble cations and six anions in the earthworm casts by capillary zone electrophoresis to determine their content in casts compared to soil. For three of the five species studied this is the first information obtained on the matter. The obtained data demonstrated that soil type has the biggest impact on the observed changes in the cast ion content, probably due to the differences in the initial concentrations and soil properties. Within each soil type, the observed effects were mostly species-specific, and the species belonging to the same ecological group (endogeic and epi-endogeic) did not have similar effects. The exposure to different earthworm species resulted in pronounced differences in the concentrations of magnesium, calcium, ammonium, and chloride, while the soil type had the highest impact on sulfate, fluoride, acetate, and sodium ions. Therefore, the terms ‘ecological group’ and ‘functional group’ are not equivalent for earthworm casts, and replacing an earthworm species with another belonging to the same ecological group may result in changes of the soil ion composition.

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Ślady po kryształach halitu w dolomitach dewońskich w kamieniołomie Zachełmie

Jaworska J.

Przegląd Solny

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2017

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T. 13

135--140

PL

Nieczynny kamieniołom w Zachełmiu jest znany z racji odkrycia i opisu śladów najstarszego lądowego kręgowca – tetrapoda. W tym samym kamieniołomie znaleziono dobrze zachowane 3 ślady po pojedynczych kryształach halitu (na 2 próbkach skał). Wielkość śladów po tych kryształach wynosi od 1 do ok. 2,5-3 cm. Przypuszczalnie jeden ślad zostawił kryształ sześcienny, a 2 ślady powstały po kryształach typu hopper. Kilkakrotnie szczegółowo przebadane i opisane utwory dolomitowe z tego miejsca wskazują, że środowiskiem ich depozycji była płytka, rozległa laguna odsłaniająca kilkakrotnie dno i okresowo sprzyjająca sedymentacji ewaporatów. W niniejszym artykule autorka rozważa możliwość miejsca oraz czasu krystalizacji halitów, tzn. czy te kryształy wytrąciły się z roztworu w zbiorniku, czy też nieco później, już w obrębie osadu węglanowego, na skutek penetracji sedymentu przez solanki. Oba „miejsca” i czas precypitacji halitu wydają się równie prawdopodobne.

EN

The abandoned Zachełmie Quarry has been known for the discovery and descriptions of the trackways of a tetrapod, the oldest land vertebrate animal. Three well-preserved casts of single halite crystals were found on two salt samples collected from the same site. The sizes of the halite traces range from 1 to ca. 2.5-3 cm. Most certainly, they are two casts of hopper and one of cube form crystals. The local dolomite formations, studied and described several times in detail, indicate that a shallow and vast lagoon that had uncovered the sea bottom several times and periodically allowed for the sedimentation of evaporites was the sedimentation environment. In this paper, the author considers possible place and time of halite crystallisation, i.e. whether the crystals were precipitated from the basin’s solution or somewhat later, as a result of brine penetration through the carbonate sediment. Either halite “location” and precipitation time seem to be equally probable.

3

Investigate the Possibility of Tekcast Methods Used for Casting Polymeric Resin Materials

Mäsiar H., Repka L., Lipták P., Híreš O.

Archives of Foundry Engineering

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2014

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Vol. 14, iss. 2

116--122

EN

Contribution gives an overview of knowledge about the method of centrifugal casting with orientate on Tekcast system. Company Tekcast Industries has developed a device for centrifugal casting, extending the area of production of castings or prototyping of metal or plastic. Materials suitable for the centrifugal casting with flexible operating parameters may include non-ferrous metal alloy based on zinc or aluminum or non-metallic materials such as polyester resins, polyurethane resins, epoxy resins, waxes and the like. The casting process is particularly suitable for a wide range of commercial castings and decorative objects.

4

Określenie wpływu zastąpienia żelazokrzemu węglikiem krzemu a także odpadem złożonym z węglika krzemu i krzemu krystalicznego na własności wlewków i odlewów

Różański P., Pogorzałek J., Bulkowski L., Stecko J., Marcisz J.

Prace Instytutu Metalurgii Żelaza

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2012

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T. 64, nr 3

88-91

PL

Celem pracy było zbadanie możliwości zastąpienia szeroko stosowanego drogiego żelazokrzemu odpadem, złożonym z węglika krzemu i krzemu krystalicznego, jako nośników krzemu, odtleniacza i modyfikatora struktury wlewków. Wykonano badania materiałowe odpadu z przemysłu elektronicznego złożonego z węglika krzemu i krzemu krystalicznego, laboratoryjne i półprzemysłowe próby otrzymania węglika krzemu z tego odpadu, porównawcze wytopy laboratoryjne stali z wykorzystaniem odpadu, badania metaloznawcze uzyskanej stali. W wyniku stwierdzono, że wykorzystanie odpadu na osnowie krzemu krystalicznego i węglika krzemu w metalurgii stali i w odlewnictwie wymaga odpowiedniego przygotowania, polegającego na aglomeracji zapewniającej zwiększenie jego rozpuszczalności w kąpieli metalowej. Nie stwierdzono ujemnego wpływu zastosowanego odpadu na wielkość uzysku na drodze ciekła stal - wlewek, makrosegregację pierwiastków oraz makrostrukturę i mikrostrukturę stali. Stwierdzono możliwość pełnej syntezy zawartego w odpadzie krzemu krystalicznego i węgla do postaci węglika krzemu oraz szansy na oszczędność w wyniku zastąpienia żelazokrzemu tym odpadem, nawet przy zwiększonych kosztach związanych z jego przygotowaniem i stosowaniem.

EN

The purpose of the work was to examine the possibility of replacement of widely used expensive ferrosilicon with a waste consisting of silicon carbide and crystalline silicon, as silicon carriers, deoxidiser and ingot structure modifier. The materials testing of the electronic industry waste consisting of silicon carbide and crystalline silicon, laboratory and semi-industrial tests for obtaining silicon carbide from this waste, comparative laboratory melts of steel using the waste and material evaluations of obtained steel were carried out. As a result, it has been found that the use of crystalline silicon and silicon carbide-based waste in the steel metallurgy and foundry engineering requires a suitable preparation, which is the agglomeration to ensure the increase in its solubility in metal bath. No negative impact of the waste on yield on the liquid steel - ingot way, macrosegregation of elements and steel macrostructure and microstructure was found. The possibility of full synthesis of crystalline silicon and carbon contained in the waste to silicon carbide and saving opportunities as a result of replacement of ferrosilicon with this waste, even with increased costs related to its preparation and use, were found.

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The influence of the basic styrofoam patterns final shaping parameters on the resistance properties

Pacyniak T., Buczkowska K.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 4

121-126

EN

This work presents the analysis of the final shaping process of the patterns aimed at determining the influence of the pressure and the time of sintering on the resistance to bending. The analysis of the research results proved that when the pressure of the sintering rises and reaches Ps=2.1 bar the resistance to bending increases, above this level of the pressure the resistance value starts decreasing. The time of styrofoam sintering at which the highest bending resistance values were obtained is ts=90 s. When the sintering pressure is less than 2 bar prolongation of the time of sintering over 90 s causes a slight increase in the resistance, however, at higher pressures prolongation of the time of sintering causes submelting of the styrofoam pattern.

6

The analysis of the influence of the polystyrene patterns shaping parameters on the resistance properties

Pacyniak T., Buczkowska K., Bogus W.

Archives of Foundry Engineering

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2012

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Vol. 12, iss. 2

227-234

EN

This work presents the technology of making foam plastics patterns used in casting as well as the final shaping stand. The analysis of the sintering process was carried out aiming at determining the influence of the pressure and the time of sintering on the flexural strength properties. The analysis of the research results confirmed that when the sintering pressure grows to the value of Pa =1,7 bar the flexural strength also increases, when the pressure value is higher than that, the degradation of the material takes place and the strength properties decrease.

7

The role of Lumbricus rubellus Hoffm. in determining biotic and abiotic properties of peat soils

Makulec G.

Polish Journal of Ecology

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2002

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Vol. 50, nr 3

301-339

EN

The field study was conducted on fifteen peat meadows located in the Biebrza river valley, north-eastern Poland, to estimate the range of changes in Lumbricidae communities with time after drainage. In a field experiment, the effects of L. rubellus were examined on the composition and abundance of microflora, Nematoda, Collembola, and Enchytraeidae, and on resources of exchangeable nutrients in drained peat soils. The occurrence of 2-6 earthworm species was noted in soils of drained peats. L. rubellus appeared already 3-5 years after drainage and rapidly reached high densities and biomass. It showed preference for moderately or heavily moorshed soils, with high contents of total nitrogen and phosphorus, low C/N, moderate porosity, and moderate moisture. Casts of this species contained more fungi and cellulolytic microorganisms, while less bacteria and actinomycetes, as compared with their contents in the soil. Also urease activity, content of fulvic acids and concentrations of exchangeable phosphorus, magnesium, and potassium were higher in casts. In a 4-month field experiment, different densities of L. rubellus were used: 2,4, and 6 individuals in 1.5 L isolators inserted to soil. The control variant was without earthworms. It was found that high L. rubellus densities in peat moorsh enhanced bacteria, ammonifying microorganisms, microorganisms utilising mineral nitrogen, and seasonally also actinomycetes and cellulolytic microbes. Also total microbial biomass, dehydrogenase activity, and the rate of cellulose decomposition were higher. The abundance of soil fungi noticeably decreased. Moreover, L. rubellus significantly influenced nemathode composition and abundance. Within a short time, their total numbers declined, especially numbers of bacterial-feeding nematodes. Also numbers an proportions of fungivorous nematodes slightly declined. Plat-feeding nematodes were least affected by this species, and in some periods their numbers were higher in the presence of earthworms than in the control. In the field experiment, no noticeable effect of earthworms was found on total enchytraeid numbers. In the period of autumn peak of Collembola, high numbers of L. rubellus reduced their densities. By modifying the composition and abundance of microflora, nemathodes and mesofauna high L. rubellus densities (above 200 individuals m^-2) can increase the rate of organic matter mineralization, intensify competition for nutrients, and indirectly they contribute to the biological decomposition of moorsh in soils of drained peat meadows.

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Microfloral abundance and enzymatic activity of Lumbricus rubellus Hoffm. (Oligochaeta: Lumbricidae) casts in peat meadow soils

Makulec G., Chmielewski K.

Polish Journal of Ecology

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2002

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Vol. 50, nr 3

381-387

EN

The abundance of the main microfloral groups, and dehydrogenase and urease activity, in the casts of Lumbricus rubellus Hoffm. and in the 0-5 cm and 5-10 cm soil layers of drained peaty meadows were compared. The abundance of microorganisms in cast was significantly higher than in the soil, as was the level of enzyme activity. The difference was particularly marked in comparisons with the 5-10 cm soil layer. In the cases of fungi, bacteria and actinomycetes, the degree to which abundance was greater in casts was highest at sites where the abundance of microflora in the soil was low. The activity of the two enzymes was always higher in casts than in soil, and the difference was especially marked for the meadow on alder peat.

9

Zmiana geometrii frontu krystalizacji w strefie kryształów kolumnowych w odlewach krzepnących pod wpływem pola magnetycznego

Szajnar J.

Archiwum Odlewnictwa

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2001

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R. 1, nr 2

379--384

PL

Opracowano model frontu krystalizacji z uwzględnieniem zmian stężenia miedzi wywołanych działaniem konwekcji wymuszonej wirującym polem magnetycznym. Zmiany geometrii frontu oparto na modelu komórkowym Kurza-Fishera i zmodyfikowanym modelu paraboidalnym użytym w kryterium stabilności marginalnej Mullinsa-Sekerki. Wyznaczony kształt powierzchni rozdziału wykorzystano do przeprowadzenia symulacji przepływu ciekłego metalu przed frontem krystalizacji.

EN

In the paper, the theoretical model of crystallization front was worked out, taking into consideration changes in Cu concentration caused by forced convection. The changes of front geometry were based on the modyficated by K-F parabolic model of crystallization front. Calculated interface shape was used for making simulation of liquid metal flow in front of interface.

10

Optymalizacja systemu produkcji odlewów w Metalexport - Odlewnia Koluszki Spółka z o.o.

Lisowski J., Cyprys A., Pietrowski S.

Archiwum Odlewnictwa

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2001

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R. 1, nr 1

253--265

PL

W pracy przedstawiono charakterystykę Odlewni Koluszki Sp. z o.o. – Metalexport. Podano wielkość i strukturę sprzedaży odlewów. Omówiono zmiany w zakresie optymalizacji systemu produkcji odlewów w celu obniżenia kosztów wytwarzania.

EN

In paper present characteristic Foundry of Koluszki. Largeness serve and structure of sale of cast. It discuss changes in range of optimization of production system of cast for cost drop of manufacturing.