Abstract:
Objective The aims were to study the contents of Pb and Cd in leaves and fruits of Vaccinium uliginosum L. under natural habitats in the Greater Khingan Mountains, which provided basic data support for the absorption characteristics of Pb and Cd in plant and soil.
Methods Taking the natural population of Vaccinium uliginosum L. in the Greater Khingan Mountains as the research object, the absorption characteristics of Vaccinium uliginosum L. to Pb and Cd in soil were determined by analyzing and applying models fitting the contents of Pb and Cd in leaves, fruits and soils. The environmental factors affecting Pb and Cd contents in Vaccinium uliginosum L. leaves and fruits were identified by correlation analysis. Finally, the pollution degree of Pb and Cd in Vaccinium uliginosum L. leaves and fruits were determined by standard comparison method and potential ecological risk assessment method.
Results ① The contents of Pb and Cd in soil, leaf and fruit showed moderate spatial variations. ② The migration coefficients (CRs) of Pb and Cd from soil to leaf and fruit of Vaccinium uliginosum L. decreased with the increase of Pb and Cd contents in soil, which could be well fitted by Langumir curve model. ③ The higher alkali-hydrolyzed nitrogen was beneficial to the absorption of Pb by leaf and fruit, and the higher available Cd was beneficial to the absorption of Cd by leaf and fruit. ④ The Pb contents in leaf of Vaccinium uliginosum L. in the Greater Khingan Mountains were higher than the limit value of the National Food Standard (GB2762-2017), the Pb contents in fruit and Cd contents in leaf and fruit of Vaccinium uliginosum L. were far lower than the limit value of National Food Standards (GB 2762—2017). The potential ecological risks of Pb and Cd in fruits were very low.
Conclusion The Langumir curve model could well fit the absorption characteristics of Pb and Cd by Vaccinium uliginosum L. leaf and fruit in the Greater Khingan Mountains. The potential ecological risks of Pb and Cd were low.