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The impact of adding a natural clay sorbent such as halloysite on the content of selected heavy metals in the biomass of common orchardgrass (Dactylis glomerata L.) was studied in a pot experiment. The study was conducted on mucky soil enriched anthropogenically with heavy metals, whose values exceeded permissible standards of soil quality and values of the geological background. The experiment included three variants with differentiated percentage of halloysite, i.e. 10%, 30% and 50%, as well as two control cultivations. The results confirm the impact of halloysite on the physicochemical properties of soil, consisting in increased soil pH and sorption capacity. Addition of halloysite to soil also differentiated the quantity of crop yield and concentration of heavy metals in the plant and soil. Halloysite was found to have an inconsistent impact on the concentration of heavy metals in the biomass of common orchardgrass, which was proven by some elevation in the level of heavy metals and a higher bioaccumulation factor (BAF). Halloysite constituting 50% of the mass of substrate substantially increased the consumption of Pb and reduced the sorption of Cr. Addition of halloysite stabilised Zn and Cu in soil. The results of our preliminary investigation indicate that addition of halloysite to soils with excessive concentrations of heavy metals influences the level of soil sorption to the extent which may be effective for soil remediation.
In this field experiments, sandy loam soil was treated with different concentration of herbicide (Quizalofop-ethyl) 0.5, 1.0, 1.5 and 2 per cent. Sesbania sesban L. seeds were sown in all treated soil. The germination percentage, morphological and enzymes activities were measured after 20, 40 and 120 days. The results indicate that the germination per cent, morphological parameters were increased in control then it was gradually decreased with increasing the herbicide concentration. The enzymes like catalase and peroxidase activity were increased in control then it was decreased with increasing the concentration. Whereas the polyphenoloxidase acticity was lower in control and it was increased with increasing the herbicides concentration. Hence, after 120 days plants were harvested and the plant powder was analyzed for absorption of herbicide by plant with the help of Gas chromatography mass spectrum (GCMS). The obtained data showed that herbicide absorption was concerned in quiazalofop-ethyl treated plant when compared to control. This study expose that herbicide reduced by Sesbania sesban L.
Mining association rules (MAR) are applied in elucidating on the abundances and association of Fe minerals in soils within the proximity of an abandoned manganese oxide (MnO^) mine. Four hundred soil samples were obtained from a 4 km2 area close to the abandoned mine in Kgwakgwe, Botswana. The Fe minerals in the soil samples were identified by x-ray diffractometry. Results depicted haematite and goe- thite present in different abundances: none, trace, minor and major in soils from the study area but only haematite in soils from the control site. From 16 possible combinations of the two Fe minerals in the soil samples, MAR results for confidence, certainty factor, lift and support, depicted haematite in major quan­tity to be the most influential. This fact is substantiated by its occurrence in the country shales.
In this experiment the effects of lead and lead-free petrol applied at the following doses of: 0, 2, 4 and 6 cm(3) . kg(-1) of soil on growth and development of triticale and biochemical properties of the soil were studied. For detoxication of petrol organic amendment with barley straw was applied. The experiment was performed in two experimental series with and without triticale cover. It was found that soil contamination by petrol adversely affected growth and development of tested crops. Barley straw appeared to be ineffective in detoxication of the contaminated soil. Lead and lead-free petrol (irrespective of plant cover and application of straw) adversely affected activity of soil dehydrogenases and urease. Straw application and growing of triticale positively affected biochemical properties of the soil. These positive effects were diminished by petrol, irrespective of the lead addition. Biochemical index of soil fertility calculated on the basis of enzymatic activity and carbon content was negatively correlated with the level of soil contamination by petrol and positively with triticale yield.
The objective of the study was to evaluate the impact of liming and the application of waste organic material, i.e. sewage sludge, on the content and distribution of nickel in the fractions extracted with the BCR procedure from soil contaminated with this metal. The study was carried out on soil after a 3-year pot experiment, which included the following factors: I – nickel used in the incremental amounts 0, 50, 100 mg Ni kg-1 soil; II – liming (0 Ca and Ca according to 1 Hh of soil); and III – the addition of sewage sludge (with and without the addition of sewage sludge at the introducing dose of 2 g C kg-1 soil). The test plant was cocksfoot harvested four times (four swaths) in each plant growing season. The total content of nickel was determined with ICP-AES and its fractions with the three-stage BCR procedure. The introduction of nickel into the soil resulted in an increase in its total content and in all fractions as well as in its percentage in the exchangeable fraction. Liming reduced the mobility of nickel and decreased its content in the reducible fraction, whil inccreasing it in the residual fraction. The application of sewage sludge contributed to an increase in the total content of nickel in soil and its proportion in the oxidizable fraction. Liming and the application of sewage sludge reduced the mobility of nickel. Lime and waste organic material (i.e. sewage sludge) were found to be suitable materials for reduction of the mobility of nickel in soil contaminated with this metal.
Physalis peruviana is one of the most promising tropical fruit plants because of its rapid growth, high yield, and nutritional quality. Th is study was designed to investigate plant development under heavy metal contamination (Cd, Pb) and responsiveness to arbuscular mycorrhizal fungi (AMF) colonization by Rhizophagus clarum and Claroideoglomus claroideum. Th e antioxidant capacity, total lipid content and fatty acid profi le in fruits, accumulation of Cd and Pb in diff erent plant parts, plant dry biomass, and mycorrhizal colonization were determined. As a result of inoculation, a considerable reduction in Cd and Pb in the fruits was observed, compared with non-inoculated plants. Th e fruit number and dry weight increased in plants associated with C. claroideum. Th ese plants also showed higher acid phosphatase activity, root protein accumulation and glomalin production. Th e type of antioxidant defense was AMF strain-dependent. Antioxidant activity and H2O2 neutralization were enzymatic rather than non-enzymatic processes in the fruits of C. claroideum plants compared with those forming an association with R. clarum. Mycorrhizal establishment changed the composition and concentration of fruits’ fatty acids. Th e ratio of unsaturated fatty acids was increased. With respect to the accumulation of bioactive compounds in golden berry the present fi ndings are important for obtaining the optimum benefi ts of mycorrhizal association under unfavorable conditions.
Large areas worldwide are polluted by cadmium (Cd) and lead (Pb). The objective of this study was to develop and verify a simple model for phytoextraction of Cd and Pb. Consequently, a new model was developed based on soil and plant responses to Cd and Pb pollutants. Polluted soils were packed into some pots. Land cress and spinach seeds were germinated in the pots. Results showed the more Pb and Cd-tolerance of land cress compared to spinach. Land cress dry matter was about 50 times more than that of spinach at same contaminations. For spinach, there was a threshold soil Pb concentration (600 mg kg⁻¹), beyond which plant is more efficient to uptake Pb. Results also indicated that the proposed model with linear sorption isotherm can reasonably well predict the time needed for remediation of soil Pb. However, the model could not provide a reasonable prediction for Cd remediation.
The purpose of this study was to determine the effect of soil properties and Cd or Pb addition on the transformations of Pb in soils and its distribution between different fractions determined according to Tessieret al. The study was carried out in model pots filled with mineral or organic soils taken from the surface soil layer. The soils showed either acidic or neutral reactions. The mineral soil (Haplic Podzols) has the granulometric composition of light loamy sand. The soils were altered with the addition of: 0 mg kg⁻¹ of Cd or Pb (control sample); 10 mg kg⁻¹ of Cd in the form of Cd(NO₃)₂; 100 mg kg⁻¹ of Pb in the form of Pb(NO₃)₂. Speciation data indicate that in non-adjusted mineral soil, lead was associated mainly with Fe-Mn oxide and residual fractions (near 80% of total Pb), and relatively small amounts of Pb with others forms. In non-adjusted organic neutral soil, the dominant fractions of Pb were Fe-Mn oxide bound (56%) and organic (24%), while in organic acidic soil: organic (42%), exchangeable (21%) and Fe-Mn oxide bound (19%) fractions. Introducing 100 mg kg⁻¹ of Pb into the mineral soil changed the Pb distribution pattern among the particular fractions, while for organic soils it did not change the Pb distribution in comparison to that of uncontaminated soils. The addition of Pb to mineral and organic soils caused an increase in Pb bound to Fe-Mn oxides and in organic neutral soil also to the organic bound fraction. In the mineral soil, significant amounts of Pb were also present in the carbonate form. A significant amount of Pb associated with the non-residual fraction (> 65%) indicates that Pb in these soils may be easily available for plants.
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Microbiological activity of zinc-contaminated soils

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Metale ciężkie, w tym także cynk, gdy dostaną się do gleby w nadmiernych ilościach, stanowią dość trwałe zanieczyszczenie, w przeciwieństwie do różnego rodzaju zanieczyszczeń organicznych, podatnych w większym lub mniejszym stopniu na degradację mikrobiologiczną. Mimo iż akumulacja metali ciężkich przez drobnoustroje jest procesem powszechnym, to nie do końca poznanym. Granice tolerancji nie są jednakowe i zależą od ich bioróżnorodności i czasu trwania imisji, a także właściwości fizykochemicznych gleby, jej struktury, zawartości materii organicznej, pH i pojemności kompleksu sorpcyjnego. Coraz częściej do oceny stanu zanieczyszczenia gleby wykorzystuje się metody biologiczne, w tym aktywność enzymów glebowych, i w nich należy upatrywać szybkiej diagnozy jakości gleb. Wskaźniki te mogą być jednak wykorzystywane tylko do oceny gleb zanieczyszczonych metalami ciężkimi, a są mało przydatne w ocenie jakości gleb zanieczyszczonych związkami organicznymi.
The nested PCR has been used to evaluate the usefulness and efficiency of different Bacillus anthracis spore isolation methods in contaminated soil samples. The best results were obtained using two methods described by Beyer et al. [1] and Cheun et al. [9]. Outer and inner pairs of primers were designed from the protective antigen gene of plasmid pXO1 as well as from genes B and C of the capsule region of the plasmid pXO2. The influence of soil types on obtained results was also studied. The type of soil samples did not affect the nested PCR results. Furthermore, the sensitivity of nested PCR and PCR – ELISA was also examined.
Changes in the contents of some selected microbiogenous elements (Cu, Mn, Fe, Zn) in haulms and tubers, yield of tubers and content of nitrates in potatoes grown in soil contaminated with cadmium were evaluated in pot experiments. Under conditions of constant supply of N, P, and K, the natural cadmium reserve in soil (0.21 mg Cd·kg⁻¹) was adapted with supplements of Cd (NO₃)₂, to content of 0.4, 1, 2 and 4 mg Cd·kg⁻¹. Increasing Cd levels in soil showed an irregular effect on content of some microelements in potato plants of the Impala cv. As compared with all other variants, a statistically highly significant increase of Cu, Mn, Fe and Zn content in tubers was observed at the level of 1 mg Cd·kg⁻¹. In haulms, on the other hand, there was highly significant decrease in contents of Cu, Mn, Fe and Zn at the level of 2 mg Cd·kg⁻¹. As compared with tubers, a markedly higher content of all microbiogenous elements under study was found in the haulms. Content of Cd in potato haulms and tubers increased highly significantly with its increasing content in soil. Cadmium was accumulated above all in haulms where its content was several times higher than in tubers. The approved limits of Cd, Cu, Mn, Fe and Zn contents in potato tubers were not exceeded in any of our experimental variants. Increasing doses of cadmium did not influence the yield of tubers. Content of nitrates in tubers did not exceed the approved limit of 300 mg NO₃⁻·kg⁻¹ of fresh tubers in none of our experimental variants.
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