Comparison of Extraction Procedures for Assessing Soil Metal Bioavailability of to Wheat Grains

摘要

Agricultural soils have been analyzed to elucidate whether the trace metal distribution changes in relation to agricultural activities and to predict environmental risk. In addition to the extractability of Cu, Mn, Ni, Pb, and Zn in soils was compared by single extraction (hydrochloric acid (HC1), ethylenediaminetetraacetic acid (EDTA), diethyl-enetriaminepentaacetic acid (DTPA), calcium chloride (CaCl_2), water (H_2O)), and sequential extraction procedures. The modified Community Bureau of Reference (BCR) sequential extraction procedure (three-step) used to extraction of metals in soil samples. The extraction capacity of the analyzed metals was found by using single extraction procedures in the order: HC1 > EDTA > DTPA > CaCl_2 > H_2O. A single correlation analysis was used to investigate the relationship between extractable metal concentrations in soil solutions and metal accumulation in wheat grains. Simple correlation analyses indicated that the extractable Pb and Ni of soils by HC1, EDTA, and DTPA single extraction procedures were significantly correlated with the metal contents of wheat grains. For CaCl_2, H_2O, and BCR extraction procedures there was a relatively poor correlation between the extractable Cu, Mn, Ni, Pb, and Zn of soils and metal contents of wheat grains.