|The extractability of Cu from marine sediment as a function of degradation of organic matter|
Gerringa, L.J.A.; Cambon, J.-P. (1991). The extractability of Cu from marine sediment as a function of degradation of organic matter. Neth. J. Sea Res. 27(2): 157-163
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579, more
|Authors|| || Top |
- Gerringa, L.J.A., more
- Cambon, J.-P.
Fulvic acids (FA), humic acids (HA) and an acid-extractable organic fraction were extracted from sediment samples taken during an aerobic slurry experiment. Dissolved organic carbon was measured in the different extracts. FAs and HAs were characterized by IR-spectroscopy and UV absorption measurements. From sediment samples taken on the same days as those for organic extractions, Cu was extracted according to a sequential extraction procedure. The extraction step using Na-dodecylsulphate (Dod) is thought to extract Cu associated with low molecular weight FAs and HAs. Changes with time in the characteristics of particulate organic matter and in the amounts of the different fractions were small. The various results, however, pointed in the same direction. The amount of FAs increased linearly with time. Probably the molecular size of the FAs and HAs decreased with time. The increase in FA and the decrease in molecular size of FAs and HAs resulted both in increasing complexation capacities of the organic acids with regard to Cu. This coincided with the increase of Cu with time in the fraction extracted with Dod. Moreover, the results indicated that during the degradation of organic matter FAs were formed out of HAs according to the socalled degradative-pathway theory.