|
Titel |
Technical note: drifting versus anchored flux chambers for measuring greenhouse gas emissions from running waters |
VerfasserIn |
A. Lorke, P. Bodmer, C. Noss, Z. Alshboul, M. Koschorreck, C. Somlai-Haase, D. Bastviken, S. Flury, D. F. McGinnis, A. Maeck, D. Müller, K. Premke |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
1726-4170
|
Digitales Dokument |
URL |
Erschienen |
In: Biogeosciences ; 12, no. 23 ; Nr. 12, no. 23 (2015-12-07), S.7013-7024 |
Datensatznummer |
250118196
|
Publikation (Nr.) |
copernicus.org/bg-12-7013-2015.pdf |
|
|
|
Zusammenfassung |
Stream networks have recently been discovered to be major but poorly constrained
natural greenhouse gas (GHG) sources. A fundamental problem is that several
measurement approaches have been used without cross-comparisons. Flux
chambers represent a potentially powerful methodological approach if robust
and reliable ways to use chambers on running water can be defined. Here we
compare the use of anchored and freely drifting chambers on various streams
with different flow velocities. The study clearly shows that (1) anchored
chambers enhance turbulence under the chambers and thus elevate fluxes,
(2) drifting chambers have a very small impact on the water turbulence under the
chamber and thus generate more reliable fluxes, (3) the bias of the anchored
chambers greatly depends on chamber design and sampling conditions, and
(4) there is a promising method to reduce the bias from anchored chambers by
using a flexible plastic foil collar to seal the chambers to the water surface, rather than having
rigid chamber walls penetrating into the water. Altogether, these results
provide novel guidance on how to apply flux chambers in running water, which
will have important consequences for measurements to constrain the global
GHG balances. |
|
|
Teil von |
|
|
|
|
|
|