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Soil Lysimeter Excavation for Coupled Hydrological, Geochemical, and Microbiological Investigations
Published on: September 11, 2016
Microbial communities in streambed sediments recovering from desiccation.
Jürgen Marxsen1, Annamaria Zoppini, Sabine Wilczek
1Limnologische Fluss-Station des Max-Planck-Instituts für Limnologie, Schlitz, Germany. juergen.marxsen@bio.uni-giessen.de
FEMS Microbiology Ecology
|January 1, 2010
Summary
Climate change impacts streams, causing droughts that affect bacterial communities. Rewetting desiccated sediments showed faster recovery in less-dried German headwaters compared to intensely dried Mediterranean streams.
Area of Science:
- Environmental microbiology
- Hydrology
- Climate change research
Background:
- Climate change increases discharge variability, leading to more frequent floods and droughts, impacting even Central European headwaters.
- Mediterranean streams are prone to drought, but Central European streams are increasingly affected.
Purpose of the Study:
- To investigate bacterial community development and microbial function recovery after rewetting desiccated streambed sediments.
- To compare the resilience of microbial communities in Central European and Mediterranean streams under drought and rewetting conditions.
Main Methods:
- Utilized a sediment core perfusion technique to simulate rewetting of desiccated streambed sediments.
- Analyzed bacterial community abundance, composition, bacterial production, and extracellular enzyme activity over 4 days of experimental rewetting.
Main Results:
- Bacterial community composition showed slight changes in less-dried German sediments but distinct changes in intensely dried Italian sediments.
- High extracellular enzyme activity persisted during drought in both locations, indicating enzyme stability.
- Microbial activities recovered to pre-drought levels within 4 days in German sediments but not in Italian sediments.
Conclusions:
- Sediment drying intensity significantly influences bacterial community structure and function recovery.
- Less intense drying in Central European headwaters allowed for greater microbial community survival and faster functional recovery compared to Mediterranean streams.
- Extracellular enzymes show resilience during drought, but overall microbial recovery is hindered by severe drying events.
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