Temperature dependence of greenhouse gas emissions from three hydromorphic soils at different groundwater levels.
Geobiology
; 7(4): 465-76, 2009 Sep.
Article
em En
| MEDLINE
| ID: mdl-19570105
ABSTRACT
Wetlands contribute considerably to the global greenhouse gas (GHG) balance. In these ecosystems, groundwater level (GWL) and temperature, two factors likely to be altered by climate change, exert important control over CO(2), CH(4) and N(2)O fluxes. However, little is known about the temperature sensitivity (Q(10)) of the combined GHG emissions from hydromorphic soils and how this Q(10) varies with GWL. We performed a greenhouse experiment in which three different (plant-free) hydromorphic soils from a temperate spruce forest were exposed to two GWLs (an intermediate GWL of -20 cm and a high GWL of -5 cm). Net CO(2), CH(4) and N(2)O fluxes were measured continuously. Here, we discuss how these fluxes responded to synoptic temperature fluctuations. Across all soils and GWLs, CO(2) emissions responded similarly to temperature and Q(10) was close to 2. The Q(10) of the CH(4) and N(2)O fluxes also was similar across soil types. GWL, on the other hand, significantly affected the Q(10) of both CH(4) and N(2)O emissions. The Q(10) of the net CH(4) fluxes increased from about 1 at GWL = -20 cm to 3 at GWL = -5 cm. For the N(2)O emissions, Q(10) varied around 2 for GWL = -20 cm and around 4 for GWL = -5 cm. This substantial GWL-effect on the Q(10) of CH(4) and N(2)O emissions was, however, hardly reflected in the Q(10) of the total GHG emissions (which varied around 2), because the contribution of these gases was relatively small compared to that of CO(2).
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Microbiologia do Solo
/
Temperatura
/
Dióxido de Carbono
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Efeito Estufa
/
Metano
/
Óxido Nitroso
Idioma:
En
Revista:
Geobiology
Assunto da revista:
BIOLOGIA
Ano de publicação:
2009
Tipo de documento:
Article
País de afiliação:
Bélgica