Jingna Du, Chongling Yan, Zhaodeng Li.Environ Sci Pollut Res.2014 (21):355–365

This study focused on the cadmium (Cd) toleranceof mangroves with application of phosphate (P) in order toexplore whether exogenous P can alleviate Cd stress on theseintertidal species. Kandelia obovata (S. L.) seedlings werecultivated in rhizoboxes under different levels of Cd and Pconcentrations. The speciation distributions of Cd in therhizosphere and non-rhizosphere sediments were examinedby sequential extraction procedures; organic acid in planttissues and soil solution was measured by high-performanceliquid chromatography; Cd and P accumulation in the plantswas also determined. Results showed that considerable differences existed in Cd speciation distributions between rhizosphere and non-rhizosphere sediments. Root activityinfluenced the dynamics of Cd, P application increased theorganic acid content in root tissues, P also increased Cdaccumulation in roots whilst lowering Cd translocation fromroot to the above-ground tissues, and a significant positivecorrelation was found between Cd and P in roots (r=0.905).It is postulated that Cd detoxification of K. obovata (S. L.) isassociated with higher Cd immobilization in the presence ofhigher P and organic acid contents in root tissue.