Specifically sorbed carbonate-bound

Exchangeable Specifically sorbed, carbonate bound Organically bound MnO bound Amorphous FeO bound Crystalline FeO bound Residual... 

Specifically sorbed carbonate-bound. Significant concentrations of trace elements can be associated with sediment carbonates. A mixture of M NaOAc with HOAc at pH 5 has been shown to extract > 99% of total carbonate present in the soils (Jackson, 1958). This method was used as a specific extractant for the determination of carbonate-bound heavy metals in soils (Tessier et al, 1979 Foerstner et al., 1981 Harrison et al, 1981 Robbins et al, 1984 Hickey and Kittrick, 1984 Krishnamurti et al., 1995a Krishnamurti and Naidu, 2000). Other reagents that were also used include 2.5% HOAc (MacLaren and Crawford, 1973 Gupta and Chen, 1975 Garcia-Mirgaya et al, 1981) and 0.05 M Na2-EDTA (Sposito et al, 1982). 

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