Abstract: Comprehensive effects of Cu, Pb and Zn in Soil on growth, yield and quality of rice have been studied through a series of pot culture experiments with a 4 level and 3 factor orthogonal design. The results of the experiments showed that when soil is polluted by single factor of Cu, Pb or Zn individually, the order of damages in terms of seriousness was Zn>Cu>Pb; when Cu, Pb and Zn were added togather into the soil with different combinations, the order of cooperative damages in terms of seriousness was Cu-Pb>Pb-Zn>Cu-Zn. In order to prevent the food chain from heavy metal pollution in eco environment, the critical values of 53, 305 and 165 mg/kg for Cu, Pb and Zn in soil respectively are suggested in the condition of combined Cu, Pb and Zu soil pollution.

Key words: soil, heavy metal, combined pollution, rice, red soil, paddy soil, ecological effect