Carbon and nitrogen stable isotopes in suspended matter and sediments from the Schelde Estuary
Middelburg, J.; Nieuwenhuize, J. (1998). Carbon and nitrogen stable isotopes in suspended matter and sediments from the Schelde Estuary. Mar. Chem. 60(3-4): 217-225. dx.doi.org/10.1016/S0304-4203(97)00104-7
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Keyword |
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Author keywords |
Scheldt River; suspended materials; estuaries; stable isotopes; carbon nitrogen |
Abstract |
The C/N and stable C and N isotope ratios (dView the MathML source, dView the MathML source) of sedimentary and suspended particulate matter were determined in the Schelde Estuary. Suspended matter was divided into 2 to 5 size fractions by centrifugation. Four major pools of organic matter were recognized: riverine, estuarine, marine and terrestrial materials. Terrestrial organic matter (dView the MathML source˜-26‰, dView the MathML source˜3.5‰, C/N˜21) is important for the sedimentary pool, but suspended matter is dominated by the marine (dView the MathML source˜-18‰, dView the MathML source˜9‰, C/N˜8), riverine (dView the MathML source˜-30‰, dView the MathML source˜9‰, C/N˜7.5) and estuarine (dView the MathML source˜-29‰, dView the MathML source˜15‰, C/N˜8) end-members. In the upper estuary, the suspended matter size fractions vary systematically in their carbon and nitrogen biogeochemistry, with the small particles having low C/N ratios, depleted dView the MathML source and enriched dView the MathML source values relative to large particles. Moreover, sedimentary and suspended matter differ significantly in terms of C/N ratios (17 vs. 8.9), dView the MathML source (-26.3 vs. -28.9‰) and dView the MathML source (+6.9 vs. 12.0‰). In the lower estuary, suspended matter fractions are similar and sedimentary and suspended organic matter differ only in terms of dView the MathML source (-23.5 vs. -20.1‰). Our data indicate that autochthonous organic matter contributes significantly to the total suspended matter and that the suspended organic matter composition cannot be explained in terms of conservative mixing of riverine and terrestrial sources on the one hand and marine sources on the other hand. |
Dataset |
- Frankignoulle, M.; Borges, A.V.; Chemical Oceanograpy Unit - Université de Liège; (2004): BIOGEST project dataset: Biogas Transfer in Estuaries, more
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