Trace gas exchange and climatic relevance of bog ecosystems, Southern Germany

• Main Author: Drösler, Matthias
• Other Authors: Pfadenhauer, Jörg (Univ.-Prof. Dr.rer.nat), Christensen, T.R. (Prof., PhD. (Universität Lund, Schweden));Matyssek, Rainer (Prof. Dr.)
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Technical University of Munich 2006
• Subjects: info:eu-repo/classification/ddc/570; Biowissenschaften; Biologie; info:eu-repo/classification/ddc/620; Ingenieurswissenschaften; wetland;bog;restoration;carbon-balance;carbon-dioxide;NEE;methane;nitrous-oxide;climate-protection; Hochmoor;Regenmoor;Renaturierung;Kohlenstoff-Bilanz;Kohlendioxid;NEE;Methan;Lachgas;Klimaschutz; Arctic; Eriophorum
• Online Access: https://mediatum.ub.tum.de/603619; https://mediatum.ub.tum.de/doc/603619/document.pdf; http://nbn-resolving.de/urn:nbn:de:bvb:91-diss20050901-1249431017

Natural mires accumulate organic substances continuously and act as carbon sinks. At a worldwide scale, the amount of carbon stored in peatlands represents about 20% of the total soil carbon stock, unless peatlands cover just 3% of the worlds land-surface. Drainage and peat cutting provoke the decomposition of the carbon pools and convert peatlands to carbon sources. Research on carbon-exchange and climatic relevance were up to now mainly focused on boreal and sub-arctic peatlands. Therefore, this project was initiated to fill a regional and thematic gap, studying trace gas exchange of natural, degraded and restored bog-ecosystems in the southern German mire belt in the forelands of the Bavarian Alps. The overall goal was to assess the carbon balance and the climatic relevance via trace gas exchange measurements and to clarify, if bog-restoration is a viable means for climate mitigation. For that purpose, a new closed chamber system was developed, as existing techniques had limitations to be applied in the frame of this study (chapter 2). The prominent properties of the chamber are the transparency and the cooling system, working without line connection. The temperature inside the chamber can be controlled to ± 1°C even on bright days. Therefore, photosynthesis is not disturbed and the measurement of the net ecosystem exchange within a small-scale mosaic of ecosystems is possible. Crosschecks with the eddy covariance technique revealed highly coincident flux-rates for CO2 (r2=0.94, 1:1 line). As prerequisite to assess the carbon balance and the climatic relevance of the ecosystems, the chamber allows sampling CH4 as well as N2O, parallel to CO2. Site selection led to a total of 12 sites with 36 plots as representative examples of the southern German bog-ecosystems in the forelands of the Bavarian Alps. The selected sites were dry former peat cut areas, drained-only bog heathlands, restored Sphagnum-lawns, restored moist bog heathlands, natural bog shrubs, natural Sphagnum-lawns, Eriophorum-hummocks and ...