Suitability of Different Extraction Agents for the Determination of Plant-Available Part of Soil Arsenic
AbstraktSeveral soil-extraction agents were tested for the determination of plant-available As showing the following decreasing order of As extractability from soil: 2 mol.l-1 HNO3 > 0.43 mol.l-1 CH3COOH > 0.5 mol.l-1 NaHCO3 > 0.01 mol.l-1 CaCl2 >= 0.005 mol.l-1 DTPA > 0.1 mol.l-1 NaNO3 > 1 mol.l-1 NH4NO3. The relationship between As released by the indidual extraction agents and As concentrations in radishes was obtained by linear-regression analysis. The As concentration in leaves seem to more closely correlate with the soil-extractable As than the concentrations in roots. The 0.01 mol.l-1 CaCl2 proved the suitable extraction agent for the evaluation of availability of the soil As by plants.