Geochemical partitioning of Cu and Ni in mangrove sediments: relationships with their bioavailability.
Sequential extraction study was performed to determine the concentrations of non-residual metal-complexes in the mangrove sediments from the Divar Island, (west coast of India). Accumulation of metal in the mangrove roots (from the same location) was determined and used as an indicator of bioavailability of metal. An attempt was made to establish a mechanistic linkage between the non-residual metal complexes and their bioavailability in the mangrove system. The non-residual fractions of Cu and Ni were mainly associated with Fe/Mn oxyhydroxide and organic phases in the sediments. A part of these metal fractions were bioavailable in the system. These two phases were the major controlling factors for Ni speciation and their bioavailability in the studied sediments. However, Cu was found to interact more strongly with the organic phases than Ni in the mangrove sediments. Organic phases in the mangrove sediments acted as buffer to control the speciation and bioavailability of Cu in the system.
National Institute of Oceanography (CSIR), Dona Paula, Goa 403004, India. Electronic address: pchak@nio.org.
Parthasarathi
P
Chakraborty
National Institute of Oceanography (CSIR), Dona Paula, Goa 403004, India.
Darwin
D
Ramteke
National Institute of Oceanography (CSIR), Dona Paula, Goa 403004, India.
Sucharita
S
Chakraborty
D003300:Copper / Q000032:analysis; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry*; D007194:India; D008670:Metals / Q000032:analysis*; D009532:Nickel / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*; D053833:Wetlands
D008670:Metals; D014874:Water Pollutants, Chemical; D003300:Copper; D009532:Nickel
Bioavailability; Copper and nickel speciation; Mangrove sediment; Metal accumulation; Metal speciation; Sequential extraction