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EN
The objective of this study was to analyze the content of heavy metals and arsenic in soil and cereal grains as well as to evaluate the possible human risk in the central region of Peru. The soil samples of corn and barley grains were collected from seven agricultural zones and the concentrations of Cu, Fe, Pb, Zn and As were determined with the method of atomic absorption flame spectrophotometry. PERMANOVA showed that the effect of the type of crop and the sampling zone significantly influence the concentrations of heavy metals and As in soil and corn and barley grains (p < 0.05). PCA for heavy metals and As in soil and grain samples of the cereals studied showed that the first two main components represented 81.03% and 94.77% of the total variance, respectively. Hazard Quotient (HQ) for ingestion was the most significant. The HQ values of Pb and As in crop soils indicated that detrimental health effects are unlikely (HQ < 1). The soil hazard index (HI) values of both crops did not exceed the threshold value of 1 (HI < 1). The carcinogenic risk level (CR) of As from ingestion of corn and barley crop soils contaminated by As was higher in children than in farmers and adults. The bioconcentration factor (BCF) of As was higher in barley grains than in corn grains. The THQ of As exceeded the target value of 1 in 100% of the barley and corn sampling sites. The RC of As in grains exceeded the acceptable risk level of 10–6 in all sampling zones.
EN
Contamination of soil and water by various heavy metals such as Cd, Pb, Ni, Cu, and Fe is increasing day by day as a result of different activities, such as industrialization and urbanization. Lead (Pb), Cadmium (Cd), and Nickel (Ni) are examples of potential heavy metals that are neither essential elements nor have any role in the process of cell metabolism, but are easily absorbed and accumulated in different parts of a plant and living beings. This study was to investigate the translocation and bioaccumulation of heavy metals such as Pb, Ni, Cd, Cu, and Fe in Urtica dionica L and soil samples from 2 sites (uncontaminated – Koliq and contaminated – Kishnica in the Republic of Kosovo). The results revealed that in the contaminated site, the mean level of all the metals in soil and different parts (root, stalk, and leaf) of the plant were found to be significantly (p < 0.01) higher than the uncontaminated site. Multivariate analysis was used to determine the distribution of metals within the study area. The trace metal contents from different parts of these plants were determined by the use of AAS. The results revealed that Urtica dionica L. translocated high amounts of metals to its organs, especially to leaves, so that translocation factors were much higher than one (> 1). However, these concentrations of heavy metals in the soil and Urtica dionica L were higher than levels specified according to the standards in UK and Germany.
PL
Jednym z podstawowych problemów, z jakim musi się zmierzyć wiele drzew na terenie zurbanizowanym, jest degradacja gleby wskutek nieprzyjaznego dla nich użytkowania obszaru w strefie rozwoju korzeni.
EN
The paper discusses existing models used to estimate the thermal conductivity of the soil medium. The considerations are divided into three general sections. In the first section of the paper, we focus on the presentation of empirical models. Here, in the case of Johansen method, different relations for Kersten number are also presented. In the next part, theoretical models are considered. In the following part, selected models were used to predict measured thermal conductivities of coarse- and fine-grained soils, at different water contents. Based on these predictions as well as on the authors’ experience, a critical assessment of the existing models is provided. The remarks as well as advantages and disadvantages of those models are summarized in a tabular form. The latter is important from a practical point of view; based on the table content, one can simply choose a model that is suitable for the particular problem.
PL
Próbki gleby zanieczyszczonej mieszaniną paliw węglowodorowych poddano działaniu ognia. Po samoistnym zgaszeniu z popiołu wyekstrahowano związki aromatyczne (2-, 3-, 4-, 5- i 6-pierścieniowe). Jako rozpuszczalnik zastosowano wodę demineralizowaną i 3-proc. roztwory wodne 5 pianotwórczych środków gaśniczych. Ekstrakt analizowano metodą chromatografii gazowej sprzężonej ze spektrometrią mas (GC-MS). Stopień wymywania węglowodorów z gleby przy użyciu środków gaśniczych wynosił 28,79–51,05%, a przy użyciu wody 1,52%.
EN
A fire was induced on 5 soil samples impregnated with a mixt. of hydrocarbon fuels. After self-extinguishing the fire, soil samples were extd. with demineralized water,n-C6 H14 and 5 types of 3% aq. solns. of foam-forming extinguishing agents. The content of 2, 3, 4, 5 and 6 ring arom. hydrocarbons was detd. in the exts. by using GC-MS. The extn. degree of hydrocarbons from soil was 28.79–51.05% and 1.52% with extinguishing agents and water, resp.
PL
Oceniano wpływ nawozowej (10 Mg/ha) i melioracyjnej (100 Mg/ha) dawki osadu ściekowego oraz poużytkowej wełny mineralnej, zastosowanych do nawożenia gleby lekkiej, na zawartość ogólną i form specjacyjnych ołowiu, miedzi i cynku. Wprowadzenie do gleby lekkiej ocenianych odpadów wpłynęło na zwiększenie zawartości Pb, Cu i Zn w stosunku do kontroli, ale nie spowodowało przekroczenia ich dopuszczalnych zawartości w glebie. Zastosowanie melioracyjnej dawki osadu ściekowego nie stworzyło zagrożenia dla środowiska glebowego ze strony metali ciężkich. Największy udział w całkowitej zawartości ocenianych metali stanowiła frakcja rezydualna (FV), następnie formy Pb związane z materią organiczną oraz formy Cu i Zn związane z wolnymi tlenkami Fe i Al. Osad ściekowy zastosowany samodzielnie i z dodatkiem wełny mineralnej wpłynął na zmniejszenie mobilności ocenianych metali ciężkich.
EN
Eight expts. were carried out in pots filled with light soil and addn. of fertilizing agents, such as NPK fertilizer, sewage sludge and waste mineral wool, used sep. or together. Soil samples were taken for 3 growing seasons and the total Pb, Zn and Cu content as well as their speciation forms were detd. The sewage sludge and its mixts. with waste mineral wool increased the content of Pb, Cu and Zn in relation to the control, but did not result in exceeding the permissible levels in the soil.
7
Content available remote Polichlorowane bifenyle w glebach o zróżnicowanym sposobie użytkowania
PL
Oceniono wpływ źródeł uwalniania polichlorowanych bifenyli (PCB) na ich zawartość w glebach i roślinach na obszarach o zróżnicowanym użytkowaniu oraz oceniono przemieszczanie się PCB w głąb profilu glebowego. Zbadano zależności pomiędzy zawartością PCB w glebie i ich zawartością w roślinach z uwzględnieniem źródła emisji. Akumulacji w glebach i roślinach ulegały przede wszystkim kongenery PCB 28 i PCB 52. Nisko chlorowane PCB przemieszczały się w głąb profilu glebowego na głębokość ok. 40 cm. Stwierdzono istotną statystycznie zależność pomiędzy zawartością PCB w badanych roślinach a ich zawartością w glebach.
EN
Soil samples were collected from 3 areas with diversified use and from layers of different depth (0–200 cm) as well as samples of plants growing in these areas. The content of polychlorinated biphenyls (PCB) in soils and plants was detd. by GC/ECD method. The PCB accumulation in soils and plants was mainly caused by PCB 28 (3 Cl atoms) and PCB 52 (4 Cl atoms) congeners. Low chlorinated PCBs moved deep into the soil profile to the depth of about 40 cm. A statistically significant relationship was found between PCB content in the tested plants and their content in soils.
8
Content available remote Bioakumulacja wybranych metali ciężkich w kukurydzy uprawianej na paszę
PL
Celem badań była ocena bioakumulacji wybranych metali ciężkich w roślinach kukurydzy, która jest uprawiana na coraz większym areale gruntów. Celem uprawy jest głównie pasza dla bydła mlecznego, którego hodowla stała się dominującym kierunkiem rozwoju rolnictwa na Podlasiu. Badania wykonano w oparciu o próbki gleb lekkich i średnich oraz próbki uprawianej kukurydzy. W próbkach gleb oznaczono zawartość ogólną kadmu, ołowiu, niklu, miedzi i cynku, oznaczono zawartość tych samych metali w roślinach. Na podstawie uzyskanych wyników obliczono współczynniki bioakumulacji w/w metali w roślinach kukurydzy. Stwierdzono, że gleby na których uprawiano kukurydzę w większości charakteryzowały się zawartością metali ciężkich na poziomie tła geochemicznego. Niewielkich część była zanieczyszczona kadmem na I poziomie wg liczb IUNG. Kukurydza ze względu na zawartość metali ciężkich spełniała wymogi opracowane dla roślin paszowych. Współczynniki bioakumulacji metali w kukurydzy były najczęściej niskie i adekwatne do niskiej ich zawartości w glebach, choć w przypadku kadmu i ołowiu wskazują na źródło poza glebowe.
EN
The aim of the study was to assess the bioaccumulation of selected heavy metals in corn plants grown on the increasing area of land used for fodder for cattle, mainly dairy cattle, whose breeding has became the dominant direction of agricultural development in Podlasie region. The study was carried out on the basis of light and medium soils samples and maize samples grown for fodder for dairy cows. The total content of cadmium, lead, nickel, copper and zinc was determined in soil samples as well as in plants. On the basis of the obtained results, the bioaccumulation coefficients of the above-mentioned metals in maize plants were calculated. It was found that the soils, on which maize was grown, were mostly characterized by the content of heavy metals at the level of geochemical background. A small part was contaminated with cadmium on the first level according to JUNG numbers. Maize, due to its heavy metal content, met the requirements for fodder plants. The bioaccumulation coefficients of metals in maize were most often low and adequate to their low content in soils, although in the case of cadmium and lead they indicate an off-soil source.
EN
The article presents issues related to biodegradation of polychlorinated biphenyls in soil by inoculation with a biopreparation IN-3 developed on the basis of microorganisms capable of metabolizing PCB. Biodegradation tests were carried out using the ex-situ technological pile method on a specially constructed test stand. As part of the research, physical and chemical analyzes of the initial soil were performed, with particular regard to the content of nutrients (nitrogen and phosphorus), PCB chromatographic analyzes and toxicological analyzes. Before inoculating soil with biopreparation IN-3, the parameters of the process were established (temperature = 17–25°C, humidity = 20–25%, pH = 7.5–7.8, content of nutrients: C:N:P = 100:10:1), which were monitored during bioremediation. During soil treatment, the content of identified PCB congeners was monitored. The assessment of biodegradation efficiency of polychlorinated biphenyls in soil was complemented by toxicological monitoring, which was carried out using live organisms representing all trophic levels: producers (PhytotoxkitTM test), consumers (Ostracodtoxkit FTM test) and reducers agents (Microtox®SPT test). Also, the presence of mutagenic factors were tested with the Ames mutagenicity test. As a result of the six-month biodegradation process of soil contaminated with aged transformer oil, upon inoculation with biopreparation IN-3, a reduction in the content of polychlorinated biphenyls from 13 153.9 µg/kg d.m. down to 1650.4 µg/kg d.m. (87.5%) was archieved. The obtained chromatographic analysis results showed that the efficiency of the PCB biodegradation depended on the number of chlorine atoms in the biphenyl ring (with the increase in the number of chlorine atoms in the PCB molecule the degree of biodegradation decreased) and the structure of the molecule (PCB congeners having 2 or more chlorine atoms in the biphenyl ring ortho positions were more difficult to biodegrade than non-ortho or mono-ortho, while polychlorinated biphenyls, in which chlorine atoms occur on only one phenyl ring, were more easily biodegradable). The toxicological analysis showed a reduction in the toxicity of the soil tested from toxicity unit TU = 26.7 to TU = 6.1. In addition, toxkit tests (PhytotoxkitTM and Ostracodtoxkit FTM) showed a decrease in inhibition of test organism growth from 69.3 to 14.8% (Ostracodtoxkit FTM test) and from 64.7–78.0 to 11.9–17.5% (Phytotoxkit test). Decreasing the mutagenicity index from 8.3 to 1.5 in the Ames test confirmed the effectiveness of the purification process. Based on the results of the experiment, conclusions were made regarding issues related to biodegradation of polychlorinated biphenyls in soil.
PL
W artykule przedstawiono zagadnienia związane z biodegradacją polichlorowanych bifenyli w glebie w drodze inokulacji biopreparatem IN-3, opracowanym na bazie mikroorganizmów zdolnych do metabolizowania PCB. Badania biodegradacji prowadzono metodą pryzmowania ex-situ na specjalnie do tego celu skonstruowanym stanowisku badawczym. W ramach prowadzonych badań wykonano analizy fizyczno-chemiczne gleby wyjściowej, ze szczególnym uwzględnieniem zawartości substancji biogennych (azot i fosfor), analizy chromatograficzne PCB oraz analizy toksykologiczne. Przed przystąpieniem do inokulacji gleby biopreparatem ustalono parametry prowadzenia procesu (temperatura = 17–25°C, wilgotność = 20–25%, pH = 7,5–7,8, zawartość substancji biogennych: C:N:P = 100:10:1), które kontrolowano w trakcie bioremediacji. W trakcie oczyszczania gleby prowadzono monitoring zawartości zidentyfikowanych kongenerów PCB. Ocenę skuteczności biodegradacji polichlorowanych bifenyli w glebie rozszerzono o monitoring toksykologiczny, który przeprowadzono przy użyciu żywych organizmów reprezentujących wszystkie poziomy troficzne: producentów (test PhytotoxkitTM), konsumentów (test Ostracodtoxkit FTM) i reducentów (test Microtox®SPT), a także wykonano badania obecności czynników mutagennych (test Amesa). W wyniku przeprowadzonego sześciomiesięcznego procesu biodegradacji gleby zanieczyszczonej zestarzałym olejem transformatorowym, na drodze inokulacji biopreparatem IN-3, osiągnięto obniżenie zawartości polichlorowanych bifenyli z 13 153,9 µg/kg s.m. do 1650,4 µg/kg s.m. (87,5%). Uzyskane wyniki analiz chromatograficznych wykazały, że efektywność biodegradacji PCB zależy od liczby atomów chloru w pierścieniu bifenylu (wraz ze wzrostem liczby atomów chloru w cząsteczce PCB maleje stopień biodegradacji) oraz budowy przestrzennej cząsteczki (kongenery PCB posiadające w pierścieniu bifenylu dwa lub więcej atomów chloru w pozycji ortho trudniej ulegają biodegradacji, aniżeli non-ortho lub mono-ortho, z kolei polichlorowane bifenyle, w których atomy chloru występują tylko na jednym pierścieniu fenylowym, są łatwiej biodegradowalne). Przeprowadzona analiza toksykologiczna wykazała obniżenie toksyczności badanej gleby ze stopnia toksyczności TU = 26,7 do TU = 6,1. Ponadto testy typu toxkit (PhytotoxkitTM i Ostracodtoxkit FTM) wykazały obniżenie zahamowania wzrostu organizmów testowych z 69,3% do 14,8% (test Ostracodtoxkit FTM) oraz z poziomu 64,7–78,0% do 11,9–17,5% (test PhytotoxkitTM). Obniżenie wskaźnika mutagenności z 8,3 do 1,5 w teście Amesa potwierdziło skuteczność przeprowadzonego procesu oczyszczania. Na podstawie uzyskanych wyników przeprowadzonego eksperymentu sformułowano wnioski dotyczące zagadnień związanych z biodegradacją polichlorowanych bifenyli w glebie.
EN
Soil erosion by water is one of the most important factors affecting contemporary landscape changes within the lowland geoecosystems in Central Europe. Soil erosion by water mainly depends on: rainfalls (especially its intensity and erosivity), length of slope and its inclination, type of cultivation and usage of land, anti-erosion treatments and susceptibility of soils to erosion. The aim of conducted research was to evaluate conditioning and magnitude of secular and extreme soil erosion processes in the Drawsko Lakeland with special considering of rainfall erosivity index (EI30). The main goal was realised through several research tasks. The first task involved examination of surface runoff and slope wash conditionings, course and quantity in the testing plot located within the Chwalimski Potok catchment. The second task was related to evaluate rainfall impact to soil erosion by water processes. It was realised by computation rainfall characteristics: intensity, kinetic energy and erosivity. In order to assess secular and extreme soil erosion impact to land relief changes, research were provided with additional details by conducting three field experiments with simulated rainfall. Stationary observation and quantitative researches of soil erosion (at testing plots) have been conducting within the Chwalimski Brook catchment for three hydrological years (2012–2014). The slope with the test area is located within the 1st order catchment being a subsystem of the Młynski Brook catchment and then followed by the upper Parsęta catchment. This area covers 4.8 hectares and is characterised by short slopes with small height variances up to 10 meters. Historically, the area was covered with agricultural crops, currently they cover about 10% of the area. The slope is covered with gleyic retisols and its average inclination is about 4 degrees with its south-east exposure. The measuring system of soil erosion covered 5 testing plots with different agricultural use (bare fallow, meadow, potatoes, spring and winter crops). Plots are 42 metres long and 4 metres width. In the bottom edge of each plot catchers with volume of 800 dm3 were installed. In this research, only data from black fallow were considered. Such tillage is recognised as a standard in soil erosion studies. Two experiments have been conducted in this testing plot. The third one has been conducted on slope located within an area of undulated morainic plateau in the Kłuda catchment. The slope is characterised by greater height variances than in Chwalimski Brook catchment. The slope, where the experiment has been conducted, is situated within local closed depression and is covered by sands underlain by boulder clay. Its average slope is about 10° with its southwest exposure. Although annual precipitation in the three-year measurement period was comparable with mean value from multi-year period (1987–2014), its intensity and erosivity were distinguishably lower. Such rainfall conditions are not favourable for extreme soil erosion by water processes, thus any relief forms from such geomorphological processes were not observed in the Drawsko Lakeland. Due to lack of that kind of forms, in 2013 and 2014, three field experiments were conducted. The main aim of experiments was to evaluate the impact of high intensity rainfall on soil surface. The first experiment consisted of 5, the second and the third of 4 rainfall simulations. The rainfall was created by using a purpose-built rain simulator, consisting of 3 and 6 sprinklers placed around the testing plot. Despite the slope inclination in the Kłuda catchment was 2.5 times steeper than Chwalimski Potok’s slope, surface runoff attained smaller volume, because of remarkably higher infiltration rate. In 2012–2014, surface runoff and soil loss has occurred 8 times each year. The maximal monthly surface runoff volume was registered in February 2012, and it equalled 10.1 dm3 m−2 and the maximal soil loss value was registered in May 2013 and equalled 3,198 kg ha−1. Annual runoff volumes were between 31.2 dm3 m−2 in 2012 and 38.8 dm3 m−2 in 2013, whereas annual soil loss values ranged from 740 kg ha−1 in 2012 to 5,700 kg ha−1 in 2013. Soil erosion values caused by simulated rainfall during field experiments were similar or significantly higher than annual values. Surface runoff was between 31.2 dm3 m−2 in the first experiment and 34.2 dm3 m−2 in the second one, whilst soil loss was between 4,632 kg ha−1 and 8,637 kg ha−1. The achieved experiment results have been compared with soil erosion rate achieved from stationary observations. The results show that runoff and soil loss considerably increase during rainfalls with high amount, intensity and erosivity. Furthermore, individual extreme erosive events may exceed annual (secular) soil erosion processes. Conducted stationary research indicates that annual soil erosion primarily depends on individual rainfall and erosive events, which considerably exceed mean values. In order to evaluate the soil susceptibility to erosion by water in the Drawsko Lakeland, high resolution potential and actual soil erosion risk maps were prepared. The qualitative assessment of soil erosion risk was based on geoinformation technologies. The model considers following conditions affecting the size of soil erosion: slope steepness and aspect, topographic factor LS (unit upslope contributing area), lithology, rainfall erosivity (Modified Fournier Index calculated from monthly and annual precipitation data) and land use and land cover from Corine Land Cover 2006. To prepare the map of potential soil erosion risk, land use from Corine Land Cover was not considered. Thematic maps have been reclassified into a 4-degree division. The results of the soil erosion risk assessment in the Drawsko Lakeland reveal the fact that a majority of its area is characterized by moderate or low erosion risk levels. Areas with high erosion risk are mostly located in the northern part of the Lakeland. The achieved results from stationary observations and field experiments may indicate that the soil loss magnitude significantly increases during rainfall with higher intensity, greater totals and accumulated in time rainfall events. This may confirm the high potential of soil erosion by water processes of above- -average magnitude and intensity in the discharge of material from agricultural used slopes.
EN
This work aims to evaluate the treated wastewater from the activated sludge treatment plant in the City of Sidi Bel Abbes (North-Western Algeria) which is required for reuse in irrigation. The control of irrigated areas downstream is done based on a pedological study. Physico-chemical analysis such as (pH, BOD5, COD and SS) indicate results in Algerian and international standards required by the WHO. The Sodium Adsorption Ratio and Electrical Conductivity values of the treated wastewater belong to the C3-S1 class. The treated wastewater has a fairly good microbiological quality that meets Algerian standards. The helminth eggs are practically absent. The concentrations of heavy metals are much lower than the limits prescribed in the Algerian decrees. Therefore, the overall processing plant efficiency is satisfactory and has the characteristics of a good treated water quality for reuse in the field of irrigation while protecting the environment. The pedological study of the soil samples shows that the most dominant fraction is undeveloped calcimagnetic. The planned irrigation plain covers an area of about two thousand hectares. Depending on the crops to irrigate; the development and nature of the necessary or recommended improvements, the proposed irrigation perimeter could be classified into five categories in which only three categories are irrigable. Water projects have been proposed to ensure the irrigation of three subdivided sectors.
EN
The study took place between 2012 and 2014 in Falenty near Warsaw, Poland, as part of a long-term scientific experiment (first began in 1987) using the randomized block method. All blocks were irrigated until 2008. In 2009 each block was divided into two areas: irrigated and non-irrigated. The study involved four levels of inorganic nitrogen fertilizer and two levels of mixed inorganic and organic fertilizer in the form of fermented cattle urine. The soil in all experimental plots was characterized by low levels of zinc, ranging from 7.6 to 16.7 mg Zn∙kg–1 dry matter. Much lower Zn content in both soil layers of all irrigated plots was associated with increased yields on these plots, regardless of the level and form of fertilizer. The content of Zn in soil and sward in 2014 year was significantly lower compared in 2012. Inadequate levels of zinc for ruminant nutrition were observed in the sward from all plots (15.4–28.8 mg∙kg–1 dry matter). The higher content of zinc was found in sward harvested from the plot, which was not fertilized with phosphorus. The long-term inorganic and fermented urine fertilization resulted in very low zinc content in the soil and meadow sward.
EN
This article discusses the ways of solving the problems of fruiting and increasing the yields, as well as obtaining high-quality standard seeds from promising seed plants of black saksaul (Haloxylon aphyllum (Minkw.) Iljin). It presents the results of studying the effect of irrigation and the use of fertilizers on the annual growth of the apical shoots of saksaul, and the effect of irrigation on the further stability of seed plants fruiting for sustainable seed supply for reproduction of saksaul deserts and forest amelioration of deserts. The morphological description of the soil by profiles has been given, and the effect of irrigation on the soils of the type II forest conditions has been described. This study was aimed at resolving the problem of fruiting frequency, increasing the yield and quality of promising black saksaul seed plants by determining the moisture dynamics in the one-meter thick soil layer under saksaul specimens for determining the methods, norms, and time of irrigating seed plants. Long-term observations show that well-developed specimens of black saksaul have appeared in the last 15-20 years on the roadside in some settlements, e.g., Bakbakty, Bakanas, Akkol, Koktal, Karoy, the motor road in village Kanshengel, Topar, Araltobe, Akzhar in the Almaty area, which passes through natural saksaul plantings and the soil with the formation of layered clay, sandy loam, and crushed stone. On the one hand, this was promoted by the presence of layered and well-aerated roadsides of the bulk roadbed, and on the other hand, by additional wetting from the runoff of precipitation from the asphalt pavement.Naturally, these saksaul plantings growing along the roads alone or in rows give a good yield when fruiting; seed plants may also be identified in these groups.
EN
This article deals with the problems of the soil cover disturbance and contamination at oil field construction. It provides a description of the set of measures aimed at ensuring the soil protection at the construction of industrial facilities at oil fields. The research object was the soil located at the interface of the wooded tundra and the southern tundra. This soil is characterized by the peculiar features that are determined by the certain commonality of the climate, as well as the similarity of the landscape evolution. The work included studying the content of the polluting matters in the tundra marshy and alluvial soddy soil located at the interface of the wooded tundra and southern tundra. The article contains a detailed analysis of the measures aimed at decreasing the impact on the soil cover during the construction of approach ways to valve stations and line facilities. The measures on the reliability and safety improvement of the pipeline operation, preservation of the stream conditions, the measures aimed at the prevention and minimization of the negative impact on the geological environment, and the measures for farsighted use and protection of soil quarries (sand and turf) have also been considered.
EN
The article deals with the determination of mobility of selected risk elements in soil samples of thermally active dump resulting from mining activities in the Ostrava region. The samples were taken from Hedvika dump during 2017 to 2018. Extraction of soil samples was performed using three-step sequential extraction of BCR (Bureau Community of Reference). Sequential extraction can provide information about the processes that normally take place in the environment. The solid soil component is gradually leached in the various extraction agents from the weakest to the strongest. This provides information on the total amount of risk elements potentially available under specific environmental conditions. Selected risk elements (Cr, Cu, Ni, Zn) were determined by ICP - MS method (Inductively coupled plasma mass spectrometry) and AAS (Atomic absorption spectrometry) (Zn). Nitric acid leaching was performed to supplement the total BCR extraction analysis.
PL
Przedmiotem artykułu jest określenie mobilności pierwiastków ryzyka w próbkach gleby termicznie aktywnego składowiska, będącego efektem działalności górniczych w regionie Ostrawy. Próbki zostały pobrane ze składowiska Hedvika w okresie 2017–2018. Ekstrakcja prób gleby została wykonana za pomocą trzystopniowej ekstrakcji sekwencyjnej BCR (Bureau Community of Reference). Ekstrakcja sekwencyjna daje informacje na temat procesów, które normalnie mają miejsce w środowisku. Składnik stały gleby jest stopniowo wypłukiwany w różnych odczynnikach ekstrakcyjnych, począwszy od najsłabszego aż do najsilniejszego. To dostarcza danych na temat ogólnej ilości pierwiastków ryzyka obecnych w określonych warunkach środowiskowych. Wybrane pierwiastki ryzyka (Cr, Cu, Ni, Zn) zostały określone za pomocą metody ICP – MS (Inductively plasma mass spectrometry) oraz AAS (atomic absorption spectrometry) (Zn). Wypłukiwanie kwasu azotowego zostało zastosowane aby uzupełnić ogólną analizę ekstrakcji BCR.
PL
Oceniono wpływ rodzaju materiału przęseł na szerokość rdzenia sprężystego pod fundamentem przyczółka. Rozpatrywano mosty betonowe, stalowe i zespolone. Analizę podanych rozwiązań przeprowadzono, przyjmując różne wartości długości mostu L, różnicy temperatury ΔT szerokości fundamentu B i odsadzek, wysokości nasypu za przyczółkiem H i wysokości gruntu od strony światła mostu h. Wyniki analizy umożliwiły określenie racjonalnej długości mostów zintegrowanych w zależności od rodzaju przęseł. Największy wpływ na szerokość rdzenia sprężystego c i jego położenie ma całkowita długość przęseł mostu L i różnica temperatury ΔT Mniejszy jest wpływ szerokości lundamentu B, wysokości nasypu H i grubości gruntu h od strony światła mostu.
EN
The impact of the type of span material on the elastic core width below the abutment footing is assessed. The study was done on concrete, steel and composite bridges. In the analysis of the proposed solutions various lengths L of bridges, temperature variations ΔT, widths of footing B and setoff, embankment height H behind the abutment and embankment height h on the side of bridge clearance were adopted. Based on the results of the analysis reasonable lengths of integral bridges depending on the type of spans can be defined. The most significant impact on width c and location of the elastic core is exerted by the overall length of bridge spans L and temperature change ΔT. Footing width B, embankment height H and thickness of soil layer h on the side of bridge clearance are of lesser importance.
17
EN
The purpose of this work was to develop a model of the interaction process between the wheeled forwarder and the soil of the cutting area, which allows evaluating the influence of soil conditions, the parameters of the wheeled forwarder, as well as load and number of cycles of its application, on the indicators of resistance and adhesion of the forwarder to the traction surface. Modeling results for 3- and 4-axle forest machines with different load levels showed that for different soil categories, types of bodies, and tire sizes. The results of the approximation analysis enabled the derive of calculation formulas for estimating the propulsive coefficient and rut depth after the first passage depending on the values of load-bearing capacity, body load coefficient, wheel width, and soil deformation module. The proposed model can be used at laying down the skidding roads and its optimization not only in economic terms but also with respect to the environment as intensive harvesting operations lead to extensive soil destructions. The practical application of the results is expressed in increased performance capacities of wood skidding operations and minimization of costs for restoring the productivity of forest area.
18
Content available remote Stabilizacja pęczniejącej ziemi w celu wykonywania budowli z ziemi
PL
Przeprowadzone badania dotyczą metod odlewania budowli z ziemi, jako część programu badawczego poświęconego budowlom ziemnym. Badano wpływ dwóch inhibitorów pęcznienia ziemi zawierającej glinę: poli(tlenku etylenu) [PTE] i karboksymetylocelulozę [KMC], aby była możliwa jej stabilizacja cementem CEM I 42,5N. Ziemię zawierającą 14% gliny, kwarc i kalcyt, stabilizowano 10% dodatkiem cementu. Dodawano równocześnie 3% plastyfikatora polikarboksylanowego w stosunku do masy cementu, aby ziemia uzyskała zdolność do płynięcia. Uzyskane wyniki wykazały, że PTE i KMC – inhibitory pęcznienia gliny, zmniejszyły to pęcznienie o około 30% i 40%, przy czym maksymalne pęcznienie odpowiadało po 90 dniach odpowiednio 24% i 46% wytrzymałości na ściskanie. Omówiono interakcję gliny z cementem i inhibitorami pęcznienia. Znalezione zależności pozwoliły na korzystne zastosowanie tych materiałów do wytwarzania elementów budowlanych, zastosowanych we wznoszeniu budynków na obszarach pustynnych.
EN
This study is concerned with the method of cast earth as part of an investigation series on earth construction. The effect of two clay swelling inhibitors; polyethylene glycol [PEG] and of carboxymethyl cellulose [CMC] on the swelling of a clay-bearing soil are studied to enable the stabilization of the soil with CEM I 42.5 N. The soil composed of 14% clay, quartz, and calcite, is stabilized with 10% cement. 3% polycarboxylate superplasticizer is added relative to the mass of the cement, to gain the soil pourable properties. The results show that the PEG and CMC clay-swelling inhibitors reduce the expansion of the soil by ~30 and ~40% and lead to a maximum increase of 24 and 46% in the 90-day compressive strength respectively. The interactions between clay, cement, and swelling inhibitors are discussed. The findings allow advantageous applications for producing building units for construction purposes in desert areas.
EN
Reliable evaluation of stress-strain characteristics can be done only in the laboratory where boundary conditions with respect to stress and strain can be controlled. The most popular laboratory equipment is a triaxial apparatus. Unfortunately, standard version of triaxial apparatus can reliable measure strain not smaller than 0.1%. Such accuracy does not allow to determine stiffness referred to strain range most often mobilized in situ i.e. 10-3 ÷ 10-1%, in which stiffness distribution is highly nonlinear. In order to overcome this problem fundamental modifications of standard triaxial apparatus should be done. The first one concerns construction of the cell. The second refers to method of measurement of vertical and horizontal deformation of a specimen. The paper compares three versions of triaxial equipment i.e. standard cell, the modified one and the cell with system of internal measurement of deformation. The comparison was made with respect to capability of stiffness measurement in strain range relevant for typical geotechnical applications. Examples of some test results are given, which are to illustrate an universal potential of the laboratory triaxial apparatus with proximity transducers capable to trace stress-strain response of soil in a reliable way.
PL
W artykule wskazano i przeanalizowano błędy jakie wynikają z konstrukcji komory standardowej. Następnie przedstawiono dwie modyfikacje aparatu, które znacząco zwiększają dokładność wyznaczania sztywności gruntu. Pierwsza modyfikacja polega na innej konstrukcji komory aparatu, która charakteryzuje się wewnętrznymi prętami łączącymi. Takie rozwiązanie pozwala na sztywne połączenie górnej części komory z dolną co pozwala m.in. na wyeliminowanie większości błędów braku współliniowości w dwóch płaszczyznach, pozwala na stały dostęp do próbki na etapie przygotowania (depozycja materiału, pomiary średnicy) a także zwiększa dokładność zadawania i pomiaru składowej wartości naprężenia pionowego. Taki rodzaj modyfikacji zwiększa dokładność pomiaru nawet o jeden rząd wielkości. Następnym etapem w doskonaleniu techniki określania charakterystyki naprężenie odkształcenie w aparacie trójosiowym są wewnątrzkomorowe systemy pomiaru przemieszczeń próbki. W artykule przedstawiono system, który według doświadczenia i opinii Autorów jest bardzo efektywny w porównaniu z innymi systemami. System oparty jest na czujnikach mikroprzemieszczeń działających na zasadzie prądów wirowych, których rozdzielczość pomiaru wynosi 1μm. System pomiarowy oparty na konfiguracji sześciu takich czujników pozwala na zwiększenie dokładności pomiaru o następny rząd wielkości. Należy podkreślić, że omówione powyżej modyfikacje aparatu trójosiowego były dokonane samodzielnie, w ramach własnej pracy badawczej a nie w drodze zakupu całego systemu dostępnego komercyjnie. W celu wykazania efektywności przedstawionych modyfikacji aparatu trójosiowego ściskania, w artykule przedstawiono wyniki pomiarów w postaci rozkładu parametrów określających sztywność gruntu tj. modułu odkształcenia E i współczynnika Poissona ν. Wyniki badań przedstawiono dla zagęszczonego i luźnego piasku drobnego przy różnych wartościach naprężenia poprzedzającego ścinanie. Zmienność parametrów przedstawiono w zależności od odkształcenia pionowego dla pomiarów wewnętrznych i zewnętrznych. Wyniki wskazują na istotny wpływ analizowanych czynników tj. zakresu odkształcenia, sposobu pomiaru i stanu materiału reprezentowanego przez wskaźnik porowatości i wielkość naprężenia na przebieg zmienności parametrów określających sztywność gruntu.
PL
W niniejszej pracy wykorzystano technikę woltamperometrii stripingowej do oznaczenia cynku oraz ołowiu w próbkach gleby pobranych z trzech różnych miejsc w Małopolsce - wszystkie trzy próbki zostały pobrane na terenie Brzeska, jedna z nich pochodzi z przydomowej grządki, druga z przydrożnego trawnika, a trzecia z lasu. Opisana została procedura przygotowania próbek oraz prowadzenia pomiarów. Podczas wykonanych eksperymentów oznaczono stężenia cynku oraz ołowiu w badanych próbkach gleb. Zastosowano ekstrakcję jednostopniową, a jako ekstrahenta użyto 10% roztwór kwasu azotowego (V). Uzyskane wyniki podane na kilogram gleby wynoszą: dla próbki pobranej z grządki: 143.35 mg/kg cynku oraz 10.55 mg/kg ołowiu, dla próbki pobranej z trawnika obok drogi: 75.5 mg/kg cynku oraz 4.93 mg/kg ołowiu, dla próbki pobranej w lesie: 169.75 mg/kg cynku oraz 19.895 mg/kg ołowiu. Wyniki odbiegają od przewidywanych, a przypuszczalna tego przyczyna jest opisana w dyskusji wyników.
EN
In this study, the voltammetry technique was used to determine zinc and lead in soil samples taken from three different places in Lesser Poland - all three samples were collected in Brzesko, one of them comes from the garden patch, the second one from roadside lawn, and the third from the forest. The samples preparation and measurements procedure are described. It was possible to determine concentrations of zinc and lead in the tested soils. One-stage extraction was used with 10% nitric acid solution as the extractant. The results obtained in mg per kilogram of soil: for the sample taken from the garden patch: 143.35 mg/kg of zinc and 10.55 mg/kg of lead, for the sample taken from the lawn next to the road: 75.50 mg/kg of zinc and 4.94 mg/kg of lead, for a sample collected in the forest: 169.75 mg/kg of zinc and 19.90 mg/kg of lead. The results are different than the expected, and the supposed cause of this is described and discussed.
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