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| Titel |
Test of a new stable isotopic fingerprinting technique (i.e. Compound Specific Stable Isotope) in an Austrian sub-catchment to establish agricultural soil source contribution to deposited sediment |
| VerfasserIn |
Modou Mbaye, Lionel Mabit, Max Gibbs, Katrin Meusburger, Arsenio Toloza, Christian Resch, Andreas Klik, Andrew Swales, Christine Alewell |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250141451
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| Publikation (Nr.) |
 EGU/EGU2017-4965.pdf |
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| Zusammenfassung |
| In order to test and refine the use of compound-specific stable isotope (CSSI) as a
fingerprinting technique, an innovative study was conducted in a sub-catchment
dominated by C3 plants located 60 km north of Vienna. This experimental site
consists of 4 different contributing sources (i.e. 3 agricultural fields and one grassed
waterway) and one sediment mixture in which the δ13C values of the bulk soil
carbon and of various fatty acids (FAs) were analysed after a cost effective sampling
strategy.
Bi-scatterplots of all possible combinations of δ13C FAs including the bulk soil carbon
δ13C showed that bulk soil carbon δ13C is a strong discriminant among the other FAs.
Moreover, bulk soil carbon δ13C values highlighted the highest difference between the four
sources and the δ13C values of C24 indicated significant differences for all sources
while δ13C of C22 did not exhibit a significant difference between the two first
sources.
An additional correlation analysis revealed that the highest significant linear dependencies
are between δ13C16 & δ13C18 > δ13C18 & δ13C24 > δ13C16 & δ13C24. Among the
variables, the bulk soil carbon δ13C was found to be the least correlated parameter,
confirming that it is the most reliable discriminator to determine the sediment origins in the
mixture.
To summarize, only the long chain FAs (i.e. C22 and C24) as well as the bulk
soil carbon δ13C succeeded in fulfilling our multivariate statistical tests. These
findings were confirmed by the mixing polygon tests and Principal Component
Analysis.
Using three different mixing models (i.e. Iso-source, CSSIAR v1.0 and MIXSIAR), the
contribution of the different sources to the mixture were evaluated. All models
highlighted that the third source (field having C3 and C4 plants in rotation) and
the grassed waterway were the main contributing agricultural area representing
25-31% and 50-57% of the deposited sediment constituting the mixture, respectively. |
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