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, L. F. and Pullaghy, C. K. (1994): Heavy metal: sources and biological effects . - In: Raj, L. C., Gaur, J. P. and Soeder, C. J. (eds): Advances in limnology series: algae and water pollution. E. Scheizerbartsche Press, Stuttgart, Germany

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Abstract  

A scheme of analysis of heavy metals in sewage based fertilizers, based mainly on direct gamma spectrometry using a Ge(Li) detector, is described. Reversed-phase anion exchange chromatography was used in separating some of the elements with mutually interfering gamma energies. The results are compared with those obtained from atomic absorption and spectrophotometric procedures.

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The level of artificial and natural radionuclide concentration as well as heavy metal content were determined in samples of saw sedge and peat collected in the Special Protection Area of peat bogs near Chelm (Poland). Gamma- and alpha-spectrometry with proper sample preparation were used to determine natural gamma-emitters, artificial 137Cs and alpha-radiating plutonium (238Pu and 239,240Pu). Non radioactive elements were determined by AAS. Rather low level of heavy metal concentration in all samples was found, however, the transfer factors were significant. Peat contamination with artificial radionuclides (137Cs and plutonium) was low. Contrary, the concentration of these isotopes in saw sedge was higher than normally observed in non contaminated areas, what is a result of a significant transfer factor.

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Cadmium, nickel or zinc contaminated soils originating from a long-term heavy metal field experiment were used to assess the influence of those particular treatments on the coexistence of various Trichoderma species. The abundance of six indigenous Trichoderma spp. - T . atroviride , T . harzianum , T . pubescens , T . tomentosum , T . virens and T . viride - were studied 12 years after the application of Cd, Zn and Ni salts on four levels (0, 30, 90 and 270 mg·kg -1 ) in a calcareous chernozem soil. Trichoderma fungal colonies from the soil particles were estimated on selective media. The isolated strains were taxonomically characterized by microscopic visualization.  A reduced Trichoderma fungal colonization was found at the lower ratio of the studied metals. No colonization could be recorded in the case of Cd, and a slightly increased abundance at Ni and Zn metal salts at the highest 270 mg·kg -1 doses. The species composition of the fungi varied considerably in the contaminated samples as a function of the metals and the applied doses. Correlation analysis revealed that the population density of T . atroviride , T . harzianum , T . pubescens , T . viride was negatively affected by the available Cd concentration. The nickel content of the soil, however, correlated positively with the abundance of T . harzianum (r = 0.955) and T . virens (r = 0.964). In addition to this finding, the frequency of T . viride and T . tomentosum showed significant positive and negative correlation with the Zn treatment (r = 0.955; r = -0.965, respectively). Great differences between the correlation and partial correlation coefficients suggested that the heavy metals may alter not only the abundance of the fungi, but the interspecific relationships among the indigenous Trichoderma population, as well. This fact is considered to have further influence on some other biotic parameters and the soil functioning in heavy-metal-affected soils.

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The applicability of the chloroform fumigation extraction method was tested for detecting soil microbial biomass and p-nitrophenyl phosphate (pNP) for acid phosphatase activity to study their response to heavy metal pollution in the rhizosphere soil of planted willow (Salix sp.).   The experimental site was located in the Toka River Valley (North-East Hungary) along the riverbank that had been severely polluted by flooding. The river had transported heavy metal and arsenic ions from several heaps deposited imprudently near a historic lead and zinc mining site. A phytoremediation experiment was set up by planting willow trees with the aim of extracting toxic elements from the soil. A strong significant difference between the control and the metal-contaminated rhizosphere soils resulted much lower microbial biomass values in the polluted soils, which suggests disturbance in the organic matter transformation dynamics. A significant increase in acid phosphomonoesterase activity was determined in the soil due to the pollution. The phosphatase enzyme production of living organisms may be stimulated by the measured higher moisture content and significantly lower LE-soluble phosphorus content of the polluted soil samples. The correlation established between soil water content and phosphatase activity was positive (r = +0.85), while that between LE-P content and phosphatase activity was negative (r = -0.69). The most important stimulating effect was attributable to the lower available phosphorus content, resulting from the heavy metal (Pb, Zn) content of polluted soil. Both measured biological parameters therefore were suitable for indicating soil pollution, but the change was adverse, the biomass decreased, while phosphatase activity increased. Microbial biomass and phosphatase activity were not correlated, indicating the different account of ecological factors that alter the biological properties of a soil.

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Abstract  

Human hair collected from the mercury, arsenic and cadmium polluted areas has been analysed by instrumental neutron activation method. The concentrations of 27 elements were compared with those of normal Japanese. Correlation coefficients of logarithmic concentrations between the elements were calculated and their significance levels were determined. Factor contribution and factor loadings of the elements were calculated for each factor by making use of principal component analysis. The factor score of each sample was also calculated for each factor to examine the effects of the contamination by heavy metals on individuals.

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. 2004 13 1815 1826 Cabala, J., P. Krupa and M. Misz-Kennan. 2009. Heavy Metals in mycorrhizal rhizospheres contaminated

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Pollack Periodica
Authors: Ivana Marko, Réka Csicsaiová, Jaroslav Hrudka, Ivona Škultétyová, Štefan Stanko, and Paula Brandeburová

. The study was divided into two parts. The first part was focus to the evaluation of the pH and conductivity of surface runoff. In the second part, the heavy metals were measured in urban stormwater. The evaluation of the measured values was by the

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Abstract  

The system 4CaO·3Al2O3·SO3-CaSO4·2H2O-Ca(OH)2 was hydrated in the presence of ten dopants, specifically soluble salts of heavy metals. When added in 10% amount, the effect of each salt is strongly evident at shorter curing times, the hydration kinetics being more favoured in the order Pb(NO3)2<K2CrO4< Cd(NO3)2< Zn(NO3)2t~Mn(NO3)3=K2MoO4<Ni(NO3)2<Cu(NO3)2<Cr(NO3)3<Fe(NO3)3. At longer curing times the differences among the systems decrease significantly. The 28-day compressive strength is almost the same for all the systems except those containing Pb(NO3)2, K2MoO4 and K2CrO4.

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Abstract  

The heavy metals bio-accumulation ability of algae was studied along the North Atlantic Morrocan coast. Instrumental neutron activation analysis was used, to determine concentrations of various elements. The k 0 standardization method was used. Some interferences corrections, particularly due to high concentrations of uranium were applied. The quality of the method was checked by using the CRM 140, a Fucus provided by IAEA. Important pollutions appear for several heavy metals from the Morrocan phosphate industry, with respect to the natural background environment.

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