Natural organic matter and iron export from the Tanner Moor, Austria

Autor(en)
Franz Jirsa, Elisabeth Neubauer, Richard Kittinger, Thilo Hofmann, Regina Krachler, Frank von der Kammer, Bernhard Keppler
Abstrakt

Samples from a pristine raised peat bog runoff in Austria, the Tannermoor creek, were analysed for their iron linked to natural organic matter (NOM) content. Dissolved organic carbon <0.45 mu m (DOC) was 41-64 mg L-1, iron 4.4-5.5 mg L-1. Samples were analysed applying asymmetric field flow fractionation (AsFIFFF) coupled to UV-vis absorption, fluorescence and inductively coupled plasma mass spectrometry (ICP-MS). The samples showed an iron peak associated with the NOM peak, one sample exhibiting a second peak of iron independent from the NOM peak. As highland peat bogs with similar climatic conditions and vegetation to the Tanner Moor are found throughout the world, including areas adjacent to the sea, we examined the behaviour of NOM and iron in samples brought to euhaline (35%.) conditions with artificial sea salt. The enhanced ionic strength reduced NOM by 53% and iron by 82%. Size exclusion chromatography (SEC) of the samples at sea-like salinity revealed two major fractions of NOM associated with different iron concentrations. The larger one, eluting sharply after the upper exclusion limits of 4000-5000 g mol(-1), seems to be most important for iron chelating. The results outline the global importance of sub-mountainous and mountainous raised peat bogs as a source of iron chelators to the marine environment at sites where such peat bogs release their run-offs into the sea.

Organisation(en)
Institut für Anorganische Chemie
Journal
Limnologica
Band
43
Seiten
239-244
Anzahl der Seiten
6
ISSN
0075-9511
DOI
https://doi.org/10.1016/j.limno.2012.09.006
Publikationsdatum
06-2013
Peer-reviewed
Ja
ÖFOS 2012
104002 Analytische Chemie, 104023 Umweltchemie
Sustainable Development Goals
SDG 14 – Leben unter Wasser
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/c5ce6f57-895c-4dea-bad7-da5fcbe60628