Elevated CO(2) Levels Affects the Concentrations of Copper and Cadmium in Crops Grown in Soil Contaminated with Heavy Metals under Fully Open-Air Field Conditions.

Guo HY Zhu JG Zhou H et al.. Elevated CO(2) Levels Affects the Concentrations of Copper and Cadmium in Crops Grown in Soil Contaminated with Heavy Metals under Fully Open-Air Field Conditions. Environmental Science & Technology 2011 45(16): 6997-7003. (IF 4.827 环境科学，二区Top）

Abstract

    Elevated CO₂ levels and the increase in heavy metals in soils through pollution are serious problems worldwide. Whether elevated CO₂ levels will affect plants grown in heavy-metal-polluted soil and thereby influence food quality and safety is not clear. Using a free-air CO₂ enrichment (FACE) system we investigated the impacts of elevated atmospheric CO₂ on the concentrations of copper (Cu) or cadmium (Cd) in rice and wheat grown in soil with different concentrations of the metals in the soil. In the two-year study elevated CO₂ levels led to lower Cu concentrations and higher Cd concentrations in shoots and grain of both rice and wheat grown in the respective contaminated soil. Elevated CO₂ levels slightly but significantly lowered the pH of the soil and led to changes in Cu and Cd fractionation in the soil. Our study indicates that elevated CO₂ alters the distribution of contaminant elements in soil and plants thereby probably affecting food quality and safety.