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| Titel |
Net ecosystem exchange related to different rewetting intensities of a drained coastal fen |
| VerfasserIn |
F. Koebsch, G. Jurasinski, S. Glatzel |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250060975
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| Zusammenfassung |
| Peatlands are important carbon (C) reservoirs. Although they account for only 3% of total global area they store 550 Gt C. This corresponds to 75% of atmospheric C.
Drainage and agricultural use of peatlands cause considerable release of climate relevant carbon dioxide (CO2). Thus, rewetting measures attempt to re-activate C storage potentials of peatlands. Yet, further research is needed about the biogeochemical processes related to rewetting.
We present results of net ecosystem exchange (NEE) measurements of a rewetted coastal fen from two vegetation periods with different rewetting intensities. In 2009 mean water level was short below ground surface whilst 2010 implicated a year-round flooding. Measurements were conducted with the Eddy-Covariance method which provides quasi-continuous flux measurements on ecosystem scale.
Vegetation period 2009 exhibited a high negative NEE indicating considerable CO2 storage of the coastal fen. Flooding decreased the amount of stored CO2 for approximately 50% during the vegetation period 2010. Since a significant part of local vegetation (above all Carex acutiformis stands) was killed by the increased water level, we assume NEE to be dampened by a lower gross primary production. Additionally, the plant residuals may provide a labile C source for microbial respiration.
Flooding affects the element budget of peatlands dramatically and causes a considerable element outflow, detectable e. g. as CO2 emission. Our results display only the initial phase of flooding. Long time studies are necessary to investigate whether CO2 will be stored after a certain period of time. Nevertheless, the climate effects of flooding should be considered when rewetting measures are assessed |
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