Distribution of Different Forms of Copper in Soils As Influenced by the Growth of Cynodon Dactylon from Two Sources

The effect of growth of Cynodon dactylon from two sources on the distribution of different forms of copper in soil was studied by pot experiments. The results showed that, when soil was spiked with Cu, the vast majority of Cu content was in the residual form, and Cu content in the exchangeable form was low. As the addition of Cu increased, the Cu content increased in all different forms. However, the greatest increases were in the exchangeable and carbonate combined forms, while the organic combined form changed the least. Compared to the control group without plant cultivation, the cultivation of Cynodon dactylon on the soil significantly enhanced Cu contents and the percentages in the total Cu in the exchangeable, carbonate combined, Fe-Mn oxides combined and organic combined forms, while Cu content in the residual form significantly decreased. The enhancement was greater in the soil cultivated with Cynodon dactylon from contaminated areas than the soil cultivated with Cynodon dactylon from non-polluted area.