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Variability of The Cadmium Content In HypericumSpecies Collected In Eastern Austria
2006
Chizzola, R. | Lukas, B.
In Hypericumspecies some specimens have been found to display higher levels of the toxic heavy metal Cd than the proposed guide value of 0.5mgkg. Plant and soil samples from various regions in Eastern Austria were collected to study the variability in the Cd content of the herbs and relate it to selected soil properties and soil micronutrient contents. The soils contained between 0.01 and 0.44mgkg-¹Cd in the dry soil. Altogether about 7% of the collected plant samples exceeded 0.5mgkg-¹Cd of dry shoots, the proposed guide value for the drug Herba Hyperici. Plants low in Cd were found on sites in the Alpenvorland, the Hainburger Berge, the Eastern Viennese Basin and the Northern Limestone Alps where the levels did not exceed 0.3mgkg-¹Cd of dry shoots. Higher Cd levels in the plants were present in material from the Waldviertel, the Southern Wienerwald and the Semmering region where often bioaccumulation factors for Cd above 1 could be calculated. In these regions the soil pH and carbonate content was somewhat lower than in other regions whereas the soil organic carbon varied greatly. In the Waldviertel some plants from a field were somewhat higher in Cd than nearby plants from the natural vegetation. In a regression analysis, the soil pH, soil organic carbon and soil Cd content were the main factors influencing Cd accumulation in the plant shoots.
Afficher plus [+] Moins [-][Nutrients determination in the river Tisza [Serbia] sediment during the period of 2004-2005]
2006
Crnkovic, N. (Republicki hidrometeoroloski zavod Srbije, Beograd (Serbia). Sektor zastite zivotne sredine, Laboratorija i Kvalitet voda) | Mijovic, S. (Republicki hidrometeoroloski zavod Srbije, Beograd (Serbia). Sektor zastite zivotne sredine, Laboratorija i Kvalitet voda)
Within the pollutant analysis in sediments the total organic carbon (TOC) content is determined, as well as nutrients such as nitrogen and phosphorus. In addition to this form carbon may be present as elemental or inorganic ones, as the crucial issue for sample preparation. Total phosphorus content was determined after sample digestion with sulphuric and perchloric acid. Organic nitrogen values were determined according the Kjeldahl method. Concentrations of TC, TOC, TIC, total P, organic N and total N in river Tisza sediment samples from sites Martonos, Novi Becej and Titel during 2004 and 2005 were presented.
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