Eingeladen durch G. Wiesenberg
The environmental and ecological significance of peat soils is immense. Even though their total cover only extends to 3-5% of the world's land area, northern peatlands contain 20-30% of the world’s soil carbon stock. In the perspective of global climatic changes, it is not known how a moderate temperature rise would affect the pool of peat OM and hence the long term carbon sequestration potential.
Within the PEATWARM project, we investigated vulnerability of a Sphagnum peatland from the Jura Mountains (France) to climate change using an experimental system (Open Top Chambers – OTCs) to simulate in situ an increase in average temperature. The effect of the OTCs was especially apparent in spring and summer, with an increase of mean and maximal air temperatures of ca. 1 and 3°C respectively. We examined the effects of temperature increase along a narrow fen-bog gradient on the vegetation, above- and belowground gas fluxes, microbial diversity and activity in Sphagnum mosses and in peat and the dynamics of labile and recalcitrant OM of peat. We especially investigated the effect of the OTCs on the abundance and distribution of branched glycerol dialkyl glycerol tetraethers (GDGTs). These compounds are complex lipids of high molecular weight, recently discovered in soils. They are produced by still unknown bacteria and are increasingly used as palaeoclimate proxies. Their degree of methylation, expressed in the MBT, was shown to depend on mean annual air temperature (MAAT) and to a lesser extent on soil pH, whereas the relative abundance of cyclopentyl rings of branched GDGTs, expressed in the CBT, was related to soil pH.
Results showed that despite the short duration of the climate experiment (26 months), branched GDGT distribution was significantly affected by the temperature rise. In addition, the applicability of the MBT/CBT as proxies for the reconstruction of temperature and pH in peat was examined by analyzing branched GDGTs in a 4 m peat core collected in covering the last 7,400 yrs BP. The MBT/CBT proxies were shown to overestimate temperature and pH, especially in the top part of the bog. A new calibration of the MBT/CBT specific to peatlands could improve the accuracy of temperature and pH reconstruction in these environments.
Datum | Vortragender | Titel |
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Mittwoch H6 16:00-17:30 04.04.2012 | Dr. Arnaud Huguet Universite Pierre et Marie Curie, Paris | Bacterial tetraether membrane lipids in peatlands: application as temperature and pH proxies [Abstract] |
19.04.2012 | Prof. Dr. Jörg-Peter Schnitzler Helmholtz Zentrum München, Research Unit Environmental Simulation (EUS), Neuherberg | Isoprene & Co. – Biological and Ecological Functions in Poplar and Oaks [Abstract] |
26.04.2012 | Dr. Nadja Rüger Systematic Botany and Functional Biodiversity, University of Leipzig | Functional Traits Explain Growth Strategies of Tropical Tree Species [Abstract] |
03.05.2012 | Dr. Pete Manning School of Agriculture, Food and Rural Development, Newcastle University, United Kingdom | Can Plant Traits Predict Ecosystem Function and Services? [Abstract] |
10.05.2012 | Dr. Nathalie Pettorelli Institute of Zoology, Zoological Society of London, United Kingdom | From Roe Deer to Satellites and Vulnerability Assessments: Scaling up Difficulties or Downsizing Complexity? [Abstract] |
24.05.2012 | Dr. Hyojung Kwon Department of Plant Ecology, University of Bayreuth | Monitoring and Analysis of Ecosystem Dynamic in Carbon Exchange in Korea [Abstract] |
14.06.2012 | Dr. Inge Jonckheere FAO HQ, UN-REDD Programme, Rome, Italy | National Forest Monitoring systems for REDD+ [Abstract] |
21.06.2012 | Prof. Joachim Peinke ForWind - Center for Wind Energy Research, Oldenburg | Windenergie und die Auswirkungen atmosphärischer Turbulenzen [Abstract] |
28.06.2012 | Dr. Michael Zech Lehrstuhl für Geomorphologie, Universität Bayreuth | Development and application of paleoenvironmental and paleoclimate proxies: interrogating biomarkers and stable isotopes (dD, d18O) in soils/sediments [Abstract] |
Montag H6 17:00-18:30 09.07.2012 | Dr. Peter Leimgruber Smithsonian Conservation Biology Institute, National Zoological Park, Front Royal, VA | (Achtung: H6) Species Conservation and Geospatial Analysis—Challenges and Opportunities [Abstract] |
12.07.2012 | Dr. Christoph Küffer Institute of Integrative Biology, ETH Zürich | Model Systems for Integrative Global Change Research: from Model Organisms to Global Comparative Studies [Abstract] |
BayCEER-Kolloquium: |
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Do. 28.01.2021 BayCEER Mitgliederversammlung |
Do. 15.04.2021 - folgt - |
Do. 22.04.2021 - folgt - |
Do. 29.04.2021 - folgt - |
Ökologisch-Botanischer Garten: |
Do. 11.02.2021 Online-Veranstaltung: Mit dem Kanu durch den Regenwald. Eine Expedition in die Überschwemmungswälder Süd-Venezuelas |
13.01.2020 Why Science Communication? |
24.05.2019 Stoichiometric controls of C and N cycling |
07.05.2019 Flying halfway across the globe to dig in the dirt – a research stay in Bloomington, USA |
16.04.2019 Picky carnivorous plants? |