摘要：

The objective of the investigation was to determine the influence of chloride salinity on the bioavailability of cadmium in soil. The experiment consisted of treating a sandy loam soil with Cd(NO3)2 at two rates in combination with four rates of NaCl or CaCl2 and then assessing the availability of Cd in the soil with Swiss chard (Beta vulgaris 'Cicla'). The procedure for assessing available Cd consisted of growing Swiss chard in pots containing the treated soils, harvesting, and then determining the Cd content of plant shoots. The Cd content of the shoot was taken as the measure of available Cd. Immediately after the plants were harvested, soil samples were collected for saturation extract analysis. The extracts were analyzed for all major cations, anions, and trace metals to have input data for chemically speciating Cd in the soil solution phase. The principal result showed the Cl treatment to cause a marked increase in soluble Cd, as well as an increase in leaf Cd levels; however, the distribution of estimated Cd species in the saturation extract changed with the Cl treatment. The treatment caused the percentage of estimated Cd2+ to decrease and that of estimated CdCl+ to increase. Leaf Cd was correlated better with the estimated activity of Cd2+ than with the concentration of total Cd.

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