THE ACCUMULATION OF ARSENIC AND CADMIUM IN PLANTS AND THEIR DISTRIBUTION

Five plant species were planted in a three-year pot experiment on thre e different soils differing in soil properties and total content of As and Cd. Sandy Fluvisols (Prerov nad Labem) contained 4.4 mg As and 0. 36 mg Cd, loamy Greyzems (Kbely) 16.7 mg As and 17.56 mg Cd, and sandy loam Luvisols (Lahost!) 49.5 mg As and 0.6 mg Cd per kg of soil. Biom ass of oat, leaves and roots of spinach, radish, carrot and plants, po ds and seeds of green beans were analysed for total content of As and Cd and total mean uptake of each crop. Transferfactor (Tf) of individu al parts of plant was calculated for both elements. Results of experim ents showed the yield was affected by soil fertility not by different As and Cd soil contents. Wide range of Cd content in soil affected sig nificantly Cd concentration in all plant species. The highest differen ce was found in the species with highest Cd concentration (leaves and roots of spinach and leaves of radish) and the lowest in pods and seed s of beans. The mean accumulation of Cd was higher in leaves than in r oots. The highest concentration of Cd was determined in leaves and roo ts of spinach and in leaves of radish at greyzems Kbely. The lowest Cd concentration in the same soil was found in green beans. Plant contai ned 0.849 mg, pod 0.174 mg and seed 0.093 mg Cd.kg(-1). The Cd concent ration in plants decreased in the order greyzems > fluvisols > luvisol s. Cd uptake was affected by plant concentration and the yield of dry matter. The highest Cd uptake was by spinach plants, lower and similar by radish, carrot and oat and the lowest by green beans. As was accum ulated in the order luvisols > fluvisols > greyzems. The highest conce ntration was found in roots of spinach 5.0 mg As.kg(-1) on luvisols an d 4.61 mg As.kg(-1) on fluvisols. Lower As concentration was found in roots of radish 1.67 mg As.kg(-1) and in roots of carrot 0.79 mg As.kg (-1) on luvisols. The highest As accumulation in aboveground biomass w as found in plants of bean (3.02 mg As.kg(-1)), the concentration in o ther plants was in close margins from 0.97 in spinach leaves to 1.59 m g As.kg(-1) in radish leaves grown on luvisols. The highest As uptake was observed by oat on all three soils due to high biomass yield. Ther e was not a significant difference in As uptake between the other four species. Leaves were the dominant part in Cd uptake, but As was taken more by roots.