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Titel |
Landscape scale patterns in the character of natural organic matter in a Swedish boreal stream network |
VerfasserIn |
J. Temnerud, A. Düker, S. Karlsson, B. Allard, S. Köhler, K. Bishop |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1027-5606
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Digitales Dokument |
URL |
Erschienen |
In: Hydrology and Earth System Sciences ; 13, no. 9 ; Nr. 13, no. 9 (2009-09-03), S.1567-1582 |
Datensatznummer |
250011989
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Publikation (Nr.) |
copernicus.org/hess-13-1567-2009.pdf |
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Zusammenfassung |
This paper defines landscape-scale patterns in the character of natural
organic matter (NOM) and tests for relationships to catchment soil,
vegetation and topography. The drainage network of a boreal catchment,
subcatchment size 0.12–78 km2, in Northern Sweden was sampled in
August 2002 during a period of stable low water flow. The NOM was
characterized with UV/Vis spectroscopy, fluorescence, XAD-8 fractionation
(%humic substances), gel permeation chromatography (apparent molecular
weight), and elemental composition (C:N). The largest spatial variation was
found for C:N, absorbance ratio, and specific visible absorptivity. The
lowest variation was in fluorescence index, %humic substances and molecular
retention time. The variation in total organic carbon (TOC), iron and
aluminium concentration was more than twice that of C:N. Between headwater
and downstream sites no significant changes were distinguished in the NOM
character. At stream reaches, junctions and lakes little change (<10%) in
NOM character was observed. Common factor analysis and partial least squares
regression (PLS) revealed that the spatial variation in surface coverage of
lakes and mires could explain some of the variation of TOC and NOM character.
Our suggestion is that the mosaic of landscape elements (different amounts of
water from lakes, forest soil and mires) delivers NOM with varying
characteristics to a channel network that mixes conservatively downstream,
with possible small changes at some stream reaches, junctions and lakes. |
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