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| Titel |
Seasonal and spatial aspects of the eco-distribution of methanotrophic bacteria in floodplain soils |
| VerfasserIn |
P. L. E. Bodelier, M. Meima-Franke, M. Kamst, L. Bodrossy, N. Stralis-Pavese, M. M. Hefting, R. Laanbroek |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250029414
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| Zusammenfassung |
| METHECO is the acronym of a consortium of research groups funded by the European
Science foundation (ESF) within the EuroDIVERSITY program. The consortium
investigates the role of microbial diversity in the dynamics and stability of global
methane consumption. The consortium covers various habitats (i.e. Landfills, rice
paddies, alpine meadows, littoral wetlands, forests, arctic wetlands, peat soils and
river floodplains) and assesses the effects of natural environmental perturbation on
the function structure relationship of methane-consuming microbial communities.
Consortium members follow the same experimental and methodological scheme
using DNA and RNA based techniques (i.e. pmoA-based cloning, DGGE, micro
arrays, Real Time PCR, stable isotope probing). This paper presents the results
obtained in a river floodplain along the river Rhine in the Netherlands, a habitat
anticipated to be subjected to major changes in flooding regime due to climate
change. Experiments were carried out to assess methanotrophic diversity, methane
oxidation kinetics and spatial variability of function and structure of methane-oxidizing
communities. Flooding events affected methane consumption negatively on short
term. However, the long –term consequences of the flooding regime where the
establishment of a distinct maximum methane consumption activity exactly in the
part of the floodplain intermediate between permanently and irregularly flooded,
where moisture and organic matter content were optimal for methane cycling. The
methanotrophic community composition as analysed by pmoA micro array mirrored the
result of the activity measurements, demonstrating that the communities differed
clearly according to the flooding gradient. Diversity as assessed by micro array
and activity components (initial consumption, Vmax, Vmax/Km) were positively
correlated. QPCR analyses showed that main types of methanotrophic bacteria
were differentially distributed throughout the flooding gradient. Type I mirrored the
activity pattern with a distinct optimum in the gradient whereas type II increased with
decreasing flooding intensity. In general it can be concluded that the environment and
environmental disturbances shaped the methane-consuming microbial community
and led to differential eco-distribution of methanotrophic bacterial groups. The
relative abundance of specific subgroups controlled methane consuming activity
which makes it evident that knowledge on the microbial community composition
is necessary to predict effects of environmental disturbance on methane cycling. |
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