Distribution Of Different Forms Of Copper In Freshwater Pond Soils Of Orissa, India

Abstract

The distribution of native copper fractions in freshwater pond soils of Orissa and their relation- ship to important soil properties were studied. Total Cu and diethylene triamine penta acetic acid (DTPA) extractable Cu ranged 7.0-24.0 and 2.0-4.9 mg/kg soil, respectively, with mean values of 12.7 and 3.1 mg/kg. The amounts of exchangeable, weakly adsorbed, moderately adsorbed, strongly adsorbed and organic matter associated Cu ranged 1.7-2.6%, 3.5-6.0%, 3.3-6.6%, 0.7-2.2% and 0.8-7.2% of the total Cu, respectively. Cu occluded or bound by car- bonates or other acid-soluble mineral fractions was 1.5-6.1% of the total Cu. Most of the Cu (58-91%) was in the residual fraction. All the chemical fractions of Cu significantly correlated with each other and with the organic carbon status of the soils.