Investigation The Relationships Between The Total And Extractable Cu,Zn And Its Bioavailability

The contents and spatial distributions of Zn and Cu in yellow-red soil,yellow-cinnamon soil and shajiang black soil of Anhui province were studied. The ratios of extractable Cu,Zn extracted from three soils by using four different extractants i.e. (DTPA,0.1mol/L HCl,1mol/L NH4NO3,1mol/L NH4OAc ) were compared. The relationships between the contents of organic matter,the contents of available P,pH and the total or extractable Cu,Zn by using 4 extractants in three soils was also studied. Wheat seeds were cultivated in the contaminated soils spiking with varied concentrations of Cu and Zn in the pots, respectively. The relationships between total and extractable Cu,Zn by using different extractants, enrichment and transfer coefficient of Cu and Zn in wheat at seedling stage and the biomass of wheat at seedling stage affected by Cu and Zn were also studied. The most results as following:1 The ratios of extractable Cu and Zn by different extractants is different in three soils. The ratios of extractable Cu is higher than the ratios of extractable Zn by using four extractants (DTPA,0.1mol/L HCl,1mol/L NH4NO3,1mol/L NH4OAc ) in three soils.2 The extractant of extractable Cu used in yellow-cinnamon soil is DTPA; the extractant of extractable Cu used in yellow-cinnamon soil is 1mol/L NH4NO3; the extractant of extractable Zn used in shajiang black soil is DTPA.3 The total Cu in soil was significantly positively correlative with extractable metal by using different extractants when metal was added into soil.4 In yellow-red soil,yellow-cinnamon soil and shajiang black soil of Anhui province, most of Cu and Zn were accumulated in the root of wheat at seedling stage, little of them transfer into above-ground of wheat, the contents of Zn transfer into above-ground of wheat more than the contents of Cu.5 In yellow-red soil,yellow-cinnamon soil and shajiang black soil of Anhui province, Transfer coefficient of Cu and Zn were increased consistent with the increasing concentration of Cu and Zn in soils and decreased after inhibited the root growth,but the enrichment coefficient do not have any rule.6 In yellow-red soil,yellow-cinnamon soil and shajiang black soil of Anhui province, excessive Cu and Zn inhibited the wheat growth at seedling stage, the biomass of above-ground of wheat lowered by metal has the following order: Cu>Zn.7 In yellow-cinnamon soil, the contents of the extractable heavy metal determined with the chemical method could be used more effectively to predict uptake of heavy metals by the above-ground of wheat at seedling stage, solutions of 1mol/L NH4NO3 are the most efficient extractants that can be used in prediction heavy metal concentrations in above-ground of wheat at seedling stage; in shajiang black soil, the contents of the extractable heavy metal determined with the chemical method could be used more effectively to predict uptake of heavy metals by the root of wheat at seedling stage, solutions of 1mol/L NH4NO3 and DTPA are the most efficient extractants that can be used in prediction heavy metal concentrations in root of wheat at seedling stage.