Influence of mangrove reforestation on heavy metal accumulation and speciation in intertidal sediments.
To investigate the influence of mangrove reforestation on heavy metal accumulation and speciation in intertidal sediments, core sediments from a restored mangrove forest and adjacent mud flat in Yifeng Estuary (southeastern China) were analyzed. The chemical speciation of heavy metals (Pb, Zn, Cu, Cr and Ni) was determined according to a sequential extraction procedure. Special attention was paid to the upper 20cm of sediment, in which metal accumulation was enhanced and speciation was obviously modified. Mangrove reforestation decreased the concentrations of all metals in the acid-soluble fraction and increased metal concentrations in the oxidizable fraction. Increased Pb, Zn and Cu concentrations and decreased Ni and Cr concentrations were observed in the reducible fraction. These results suggest that mangrove reforestation facilitated the accumulation of heavy metals in the upper sediment layers but decreased their bioavailability and mobility.
Zhou
Yan-Wu
YW
School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China.
Zhao
Bo
B
Peng
Yi-Sheng
YS
Chen
Gui-Zhu
GZ
D032407:Avicennia / Q000254:growth & development / Q000378:metabolism*; D001673:Biodegradation, Environmental; D004784:Environmental Monitoring; D016468:Forestry; D019015:Geologic Sediments / Q000737:chemistry*; D019216:Metals, Heavy / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism
D019216:Metals, Heavy; D014874:Water Pollutants, Chemical