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Fertility. 5 th ed. Oxford University Press. New York. Soils and Soil Fertility TYLER, G. & OLSSON, T., 2001. Concentrations of 60 elements

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Az algériai nyersfoszfát és a szuperfoszfát hatásának vizsgálata

V. A talajtulajdonságok és a foszfortrágyák  hatása a tavaszi árpa (Hordeum vulgare) Cd-, Cr-, Co-, Ni-, Sr-, Mn-, Al- és Mo-koncentrációjára tenyészedény-kísérletben

Agrokémia és Talajtan
Authors: Erzsébet Osztoics, Péter Csathó, and László Radimszky

MACNICOL, R. D. & BECKETT, P. H. T., 1985. Critical tissue concentrations of potentially toxic elements. Plant and Soil. 85 . 107-129. Critical tissue concentrations of potentially toxic elements

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.: Tanji, K. K.) 1–17. Am. Soc. Civ. Engineers. New York. Tedeschi, A. & Dell’Aquila, R., 2005. Effects of irrigation with saline waters, at different concentrations, on soil physical and chemical characteristics. Agricultural

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Agrokémia és Talajtan
Authors: Tibor Szili-Kovács, Ágnes Bálint, Györgyi Kampfl, Krisztina Kristóf, György Heltai, Sándor Hoffmann, András Lukács, and Attila Anton

water supplies in model experiments. Acta Agron. Hung. 50. 433–440. De Sutter , T. M., Sauer , T. J. & Parkin , T. B., 2006. Porous tubing for use in monitoring soil CO 2 concentrations

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1177 1198 Kutman, U. B., Yildiz, B. & Cakmak, I. , 2011. Improved nitrogen status enhances zinc and iron concentrations both in the whole grain and the endosperm

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Christensen, T. H. , 1984. Cadmium soil sorption at low concentration. I. Effect of time, cadmium load, pH and calcium. Water, Air and Water Pollution. 24 . 105–114. Christensen T H Cadmium

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A normalization method was tested for the detection of low level chromium contamination in the soil of the Tisza River Floodplain in Hungary. The soils' so-called “total” metal concentration (strong acid extractable fraction) is the basis of many environmental evaluation methods, soil tests.  In the floodplain soils cadmium, lead, zinc and copper occur in elevated concentrations, but their chromium concentration is not significantly higher than that of the control soils.  The normalization method makes it possible to calculate the anthropogenic and geogenic chromium concentration in soil. Anthropogenic chromium was not detectable on the control sites, but a significant amount (4-14 mg/kg) was found in the floodplain soil samples. The applied normalization method proved the low level chromium contamination in the floodplain.

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relevance of heavy metal concentrations in contaminated soils. Int. J. Environ. Anal. Chem. 51. 25–46. He , Q. B. & Singh , B. R., 1993. Plant availability of cadmium in soils I. Acta Agric Scand. 43. 134

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The pot experiment - carried out in 2000 under greenhouse conditions - was set up with seven soils differing in Cd and Pb contents and three test plants ( Lolium perenne L. cv. Georgikon), lettuce ( Lactuca sativa L. cv. Balatonzöld) and white mustard ( Sinapis alba L. cv. Sirola) with four replicates. From the seven experimental soils five samples (S1-S5) were collected from agricultural areas (arable sites) and two (S6-S7) from spoil-earth, with extremely high Cd and Pb contents.  The pots, each containing 1 kg air-dry soil, were kept at constant soil moisture (60% of maximum water capacity of the experimental soils) by daily watering, while pots were watered to weight once weekly. Before sowing the test plants: 50-50-50 mg N, P 2 O 5 and K 2 O was applied to the experimental soils to maintain the same nutrient supply. The above-soil plant parts were cut after four weeks. Fresh and dry weights of plants were determined after harvest. The aim of the experiment was to obtain results of Cd and Pb uptake by different plant species in relation to the heavy metal content and different characteristics of soils. The following conclusions were drawn: No definite correlation was found between the biomass production of the three test plants and the heavy metal content of the soils at early growth stage. The heavy metal concentration range in the soils and plants differed. In the case of Pb the soil concentration interval was broader than that of the plants'. The opposite was observed for Cd, where the plants had a wider concentration interval. Comparing the Pb and Cd concentrations of above-ground plant parts, Pb concentrations varied in a narrower interval. The maximum values of Pb content exceeded the Cd content levels, although the mobility of Pb in the soil-plant system is significantly lower. The comparison of Cd and Pb concentrations of plants and soils proved these differences. The Cd concentration of plants was 8-231% of the total Cd content of soils. The Pb concentration of plants was the 0.8-28% of the total Pb content of the soils, respectively. Comparing the three plants in respect of Cd concentrations the order found was as follows: ryegrass < white mustard < lettuce. In case of Pb, the order depended on the Pb content level (lower or higher) of the experimental soil. Symptoms of phytotoxicity were observed only on lettuce plants grown on the contaminated soils (S6, S7).

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A complex investigation was performed for a polluted area using both experi-mental and computer modelling methods. Among the experimental methods the adsorption and desorption isotherms were measured to estimate the concentration dependent equilibrium in the soil-groundwater system. A new calculation method was worked out for determining the transport para-meters from results of laboratory tests. Heavy metal solution was leached through a soil column continuously. The effluent fluidum was collected, and the heavy metal concentration of the collected fractions was measured by atomic absorption spectrophotometer. As the result of the analytic process breakthrough curves were measured in laboratory scale. Due to the applied initial and boundary conditions the transport equation can be solved analytically. Using the Ogata and Banks (1961) solution of the transport equation a new curve fitting method was introduced. After several transformations of the equation a theoretical function was fitted to the measured concentration vs. time and to the concentration vs. effluent volume data. The parameters of the fitted curve could be used as the dispersion and retardation parameters of a transport model.  The water chemistry of the system controls the rate of adsorption and desorption of metals to and from sediment. Adsorption removes the metal from the water column and stores the metal in the substrate. Desorption returns the metal to the water column, where recirculation and bioassimilation may occur. Metals are probably desorbed from the soil if the salt concentration of the water increases, and in case of some metals decreases with the redox potential and with pH.  Parallel to determining the basic transport parameters of the system using the column study, the maximal equilibrium concentration of chromium-containing compounds with different oxidation states were calculated with the MINTEQ model with two variable functions (pH and redox potential). As a result of the calculations a non-liner relation was established, as at specific points the maximal equilibrium concentration of chromium increases with a high gradient. This means that there are combinations of pH and redox potential values in the case of which chromium has a high solubility. It is advisable to avoid these points in the pH-E h field if we want to stabilize the contaminant. This state is to be reached when the goal is the mobilization of the pollutant to make the soil cleaning process possible. With the introduced calculation method areas on the pH-redox potential field (at high pH and E h values) are found in which the concentration of pollutants may reach a critical value. The introduced calculation method is quick and gives results accurate enough for a pilot test.

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