Bioavailability of cadmium to celery (Apium graveolens L.) grown in acidic and Cd-contaminated greenhouse soil as affected by the application of hydroxyapatite with different particle sizes. (February 2020)

• Record Type: Journal Article
• Authors: Yang, Lanqin; Liu, Benle; Lu, Yuanyuan; Lu, Fangyi; Wu, Xiangyang; You, Wenhua; Huang, Biao
• Is Part Of: Chemosphere. Volume 240(2020)
• Publication Date: 2020-02
• Subjects: Hydroxyapatite -- Particle size -- Bioavailability -- Cadmium -- Celery; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2019.124916
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: Cadmium contamination in greenhouse vegetable fields greatly limited the sustainable production especially of leafy vegetables. Hydroxyapatite (HAP), as a common soil amendment, has been widely used in the remediation of Cd-contaminated soils, while its remediation efficiency greatly depends on its particle sizes. In this study, a rhizobag pot experiment was conducted to investigate the effects of HAP (<60 nm, <12 μm and <80 μm) on bioavailability of Cd to celery grown in acidic and slightly Cd-contaminated greenhouse soil. The results suggested that HAP with the largest particle size (<80 μm) had the best effectiveness in reducing Cd uptake especially by the edible part of celery. Specifically, the increase in HAP (<80 μm) addition from 0.5% to 3% prominently reduced Cd concentrations in celery shoot by 19.6%–76.8% as compared with the untreated group. Also, adding HAP (<80 μm) especially at 3% significantly decreased translocation factor (TF) of Cd from celery root to shoot by 30.6% and reduced bioconcentration factor (BCF) of Cd from rhizosphere soil to celery shoot by 76.4%. These were predominantly associated with the significantly increased soil pH and the subsequently decreased soil CaCl2 –Cd concentration after adding HAP (<80 μm). Overall, although rhizosphere soil pH was the key factor in controlling Cd uptake by edible celery and regulating BCF and TF of Cd, insignificant root-induced acidification had limited effect on the immobilization efficiency of Cd by HAP (<80 μm). In conclusion, HAP (<80 μm) has good potential for the remediation of Cd-contaminated greenhouse soils. Highlights: Adding hydroxyapatite (HAP, <80 μm) was the most efficient in Cd immobilization. Cadmium uptake by celery decreased as application rate of HAP (<80 μm) increased. Adding HAP (<80 μm) prominently elevated soil pH and lowered Cd availability. Decreased Cd in celery was related to increased soil pH and reduced Cd availability. Insignificant rhizosphere acidification had limited effect on Cd immobilization.