Abstract
The relative mobility of Cd, Cu, Ni, and Zn added to several soils and the simultaneous desorption and leaching of metals (Ca, Mg, K, Al, Na, heavy metals) were determined by eluting soil columns with 0.01 M CaCl2 and analyzing the metals in leachates and soil by plasma emission spectroscopy. Although soil chemical properties generally had a larger effect on the mobility of metals than did the properties of the metals themselves, Cu moved least readily through all soil columns. The least mobility of metals was observed in a mineral soil with a relatively high pH, CEC, and exchangeable base content. The liming of an acid mineral soil reduced metal mobility, but not to the extent expected from the very low mobility observed for a naturally nonacid mineral soil. The order of mobility of the metals in the soils was: Cu ≦ Zn ≤ Ni ≤ Cd. These metals were almost completely extractable by 0.1 N HCl from a limed and unlimed acid soil, but were less extractable from a nonacid mineral soil and an organic soil. This effect is attributed to partially irreversible binding of the metals in organic matter, a phenomenon inhibited by the presence of Al on organic complexation sites. The relative mobility of Cd, Cu, Ni, and Zn added to several soils and the simultaneous desorption and leaching of metals (Ca, Mg, K, Al, Na, heavy metals) were determined by eluting soil columns with 0.01 M CaCl2 and analyzing the metals in leachates and soil by plasma emission spectroscopy. Although soil chemical properties generally had a larger effect on the mobility of metals than did the properties of the metals themselves, Cu moved least readily through all soil columns. The least mobility of metals was observed in a mineral soil with a relatively high pH, CEC, and exchangeable base content. The liming of an acid mineral soil reduced metal mobility, but not to the extent expected from the very low mobility observed for a naturally nonacid mineral soil. The order of mobility of the metals in the soils was: Cu ≦ Zn ≤ Ni ≤ Cd. These metals were almost completely extractable by 0.1 N HCl from a limed and unlimed acid soil, but were less extractable from a nonacid mineral soil and an organic soil. This effect is attributed to partially irreversible binding of the metals in organic matter, a phenomenon inhibited by the presence of Al on organic complexation sites. © Williams & Wilkins 1982. All Rights Reserved.