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Extractable zinc in soils

Eight extractants (0.10 and 0.50 N MgCl2; 0.10 N CH3COOH; 1% Na2EDTA; 0.05 and 0.10 N HCl; and 0.05 and 0.10 N H2S0(4)) were tested in five soil samples using two solution : soil ratio (50 ml: 2.50 grams and 50 ml: 5.0 grams) and three lenght of extraction periods (10, 15 and 30 minutes) for the extraction of zinc. The zinc concentration of the extractants was determined by atomic absorption photometry. The data obtained showed that 1% Na2EDTA, 0.05 and 0.10 N HCl and 0.05 and 0.10 N H2SO4 solutions extract more zinc tham MgCl2 and CH3COOH solutions. The solution-soil ratio showed significant effects on the zinc extraction. The length of extraction period showed also significante effects only whem the 15 minutes was compared to the 10 minutes period of extraction.


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