 |
| Titel |
Climate and site management as driving factors for the atmospheric greenhouse gas exchange of a restored wetland |
| VerfasserIn |
M. Herbst, T. Friborg, K. Schelde, R. Jensen, R. Ringgaard, V. Vasquez, A. G. Thomsen, H. Soegaard |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1726-4170
|
| Digitales Dokument |
URL |
| Erschienen |
In: Biogeosciences ; 10, no. 1 ; Nr. 10, no. 1 (2013-01-07), S.39-52 |
| Datensatznummer |
250007910
|
| Publikation (Nr.) |
 copernicus.org/bg-10-39-2013.pdf |
|
|
|
|
|
| Zusammenfassung |
| The atmospheric greenhouse gas (GHG) budget of a restored wetland in western
Denmark was established for the years 2009–2011 from eddy covariance
measurements of carbon dioxide (CO2) and methane (CH4) fluxes. The
water table in the wetland, which was restored in 2002, was unregulated, and
the vegetation height was limited through occasional grazing by cattle and
grass cutting. The annual net CO2 uptake varied between 195 and
983 g m−2 and the annual net CH4 release varied between 11 and
17 g m−2. In all three years the wetland was a carbon sink and removed
between 42 and 259 g C m−2 from the atmosphere. However, in terms of
the full annual GHG budget (assuming that 1 g CH4 is equivalent to
25 g CO2 with respect to the greenhouse effect over a time horizon of
100 years) the wetland was a sink in 2009, a source in 2010 and neutral in
2011. Complementary observations of meteorological factors and management
activities were used to explain the large inter-annual variations in the full
atmospheric GHG budget of the wetland. The largest impact on the annual GHG
fluxes, eventually defining their sign, came from site management through
changes in grazing duration and animal stocking density. These changes
accounted for half of the observed variability in the CO2 fluxes and
about two thirds of the variability in CH4 fluxes. An unusually long
period of snow cover in 2010 had the second largest effect on the annual
CO2 flux, whose interannual variability was larger than that of the
CH4 flux. Since integrated CO2 and CH4 flux data from restored
wetlands are still very rare, it is concluded that more long-term flux
measurements are needed to quantify the effects of ecosystem disturbance, in
terms of management activities and exceptional weather patterns, on the
atmospheric GHG budget more accurately. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|