Abstract: Pot experiment and field investigation were conducted to study the effect of Cd-Zn compound pollution on purple soil cropped with wheat, lettuce, tomato and cabbage. The results show that Cd-Zn compound pollution has a synergistic effect on Zn. Low content of Cd can promote Zn uptake, exasperate its inhibition on nutrient absorption and aggravate Zn toxicity. Conversely, Cd-Zn compound pollution has an antagonistic effect on Cd. High content of Zn can restraine Cd uptake, reduce its inhibition on nutrient absorption, and thereby, alleviate Cd toxicity. Application of 500 mg Zn·kg^-1 soil is the threshold of antagonistic effect under pot experimental condition.

Key words: Cd, Compound pollution, Purple soil, Zn