Abstract:

In order to protect quality and safety of southern China vegetables and avoid heavy metal pollution of Cd, and provide a theoretical basis for guiding the safety production, this study used four common vegetables in Guangdong Province, leaf vegetables (Chinese cabbage), the root-stock (carrots), bio-control technology (pepper), beans (cowpea) for the materials, and used situ soils in different concentrations of Cadmium (Cd) pollution in the typical area of Guangdong Province for pot experiment. This study researched the difference on Cd absorption between different species of vegetables under the potted conditions, and the correlation between soil Cd content and Cd pollution of vegetables. Soil Cd pollution threshold for the safe production of different kinds of vegetables was confirmed by fitting equation. The results showed that: (1) Cd content in the 4 vegetables increases with increasing density of soil Cd. (2) Different kinds of vegetables absorb Cd differently under the same Cd pollution concentration, concentration ranked from highest to lowest was carrots>Chinese cabbage>pepper>cowpea. (3) Both total Cd content and effective state Cd in soil had significant correlation with Cd content in the 4 vegetables, effective state Cd was much better. (4) Simulated total Cd threshold in Chinese cabbage, pepper, cowpea, carrots was 0.8995, 1.8936, 119.6875, 1.0779 mg/kg，the effective state Cd was 0.5004, 0.7069, 58.875, 0.065 mg/kg, ranked from highest to lowest was cowpea>pepper>carrots>Chinese cabbage, was all higher than the current soil limited standard values.