Investigation of Cadmium and Zinc Interactions in Soils using Desorption Isotherms = Investigation of Cadmium and Zinc Interactions in Soils using Desorption Isotherms

다국어 초록 (Multilingual Abstract)

Investigation of Cd and Zn availability in four different soils as affected by the interactions of these two heavy metals was conducted using the metal desorption quantity-intensity (Q/I) isotherms. The soils were artificially contaminated with proper concentrations of Cd and Zn as CdSO4 and ZnSO4 solutions. DTPA (diethylene triamine pentaacetic acid) - extractable and water-extractable Cd or Zn from the soils were used as Qcd or Qzn and Icd or Izn factors, respectively. The coefficient of determination for Cd and Zn desorption Q/I linear regression in the soils ranged from 0.947 to 0.999, which indicated that Q and I factors were closely correlated. The buffering capacity of Cd, BCcd, in the soils decreased with increasing Zn treatments, and the BCcd values were ranged between 205.8 and 2255.6. The decreases of BCcd values were mainly dependent upon the increases of Icd factors. However, Zn buffering capacity, BCzn, decreased with increasing Cd treatments in acidic soils, and increased in neutral and calcareous alkaline soils. The BCzn values were ranged from 143.2 to 6158.0. The values of BCzn as influenced by the treatments of Cd were also controlled by the solubility of water-extractable Zn, Izn factor. The solubility of water-extractable Cd and Zn was significantly dependent upon the changes of soil pH that were impacted by the treatments of Zn and Cd, respectively. Also, the availability of Cd was higher than Zn availability in the acidic and neutral soils, but Zn was higher than Cd in the calcareous alkaline soil.