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Titel |
Phosphatase activity and organic phosphorus turnover on a high Arctic glacier |
VerfasserIn |
M. Stibal, A. M. Anesio, C. J. D. Blues, M. Tranter |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1726-4170
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Digitales Dokument |
URL |
Erschienen |
In: Biogeosciences ; 6, no. 5 ; Nr. 6, no. 5 (2009-05-27), S.913-922 |
Datensatznummer |
250003752
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Publikation (Nr.) |
copernicus.org/bg-6-913-2009.pdf |
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Zusammenfassung |
Arctic glacier surfaces harbour abundant microbial communities consisting
mainly of heterotrophic and photoautotrophic bacteria. The microbes must cope
with low concentrations of nutrients and with the fact that both the
dissolved and debris-bound nutrient pools are dominated by organic phases.
Here we provide evidence that phosphorus (P) is deficient in the supraglacial
environment on a Svalbard glacier, we quantify the enzymatic activity of
phosphatases in the system and we estimate the contribution of the microbes
to the cycling of the dominant organic P in the supraglacial environment.
Incubation of cryoconite debris revealed significant phosphatase activity in
the samples (19–67 nmol MUP g−1 h−1). It was inhibited by
inorganic P during incubations and had its optimum at around 30°C. The
phosphatase activity measured at near-in situ temperature and substrate
concentration suggests that the available dissolved organic P can be turned
over by microbes within ~3–11 h on the glacier surface. By contrast,
the amount of potentially bioavailable debris-bound organic P is sufficient
for a whole ablation season. However, it is apparent that some of this
potentially bioavailable debris-bound P is not accessible to the microbes. |
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