Articles | Volume 5, issue 6
Biogeosciences, 5, 1615–1623, 2008

Special issue: Peatlands and the carbon cycle – from local processes to global...

Biogeosciences, 5, 1615–1623, 2008

  03 Dec 2008

03 Dec 2008

Particulate organic carbon (POC) in relation to other pore water carbon fractions in drained and rewetted fens in Southern Germany

S. Fiedler1, B. S. Höll2, A. Freibauer3, K. Stahr1, M. Drösler4, M. Schloter5, and H. F. Jungkunst6 S. Fiedler et al.
  • 1Institute of Soil Science and Land Evaluation, University of Hohenheim, Emil-Wolff-Strasse 27, 70599 Stuttgart, Germany
  • 2Ludwig-Maximilians University, Department of Geography, Luisenstr. 37, 80333 Munich, Germany
  • 3Max-Planck-Institute for Biogeochemistry, Postfach 100164, 07701 Jena, Germany
  • 4Vegetation Ecology, Technical University of Munich, Am Hochanger 6, 85350 Freising, Germany
  • 5Helmholtz Center Munich, German Research Center for Environmental Health (GmbH), Institute for Soil Ecology, Department for Terrestrial Ecotoxicology, Ingolstädter Landstr. 1, 85758 Oberschleissheim, Germany
  • 6Landscape Ecology, Institute of Geography, University of Göttingen, Goldschmidtstr. 5, 37077 Göttingen, Germany

Abstract. Numerous studies have dealt with carbon (C) contents in Histosols, but there are no studies quantifying the relative importance of the individual C components in pore waters. For this study, measurements were taken of all the carbon components (particulate organic carbon, POC; dissolved organic carbon, DOC; dissolved inorganic carbon, DIC; dissolved methane, CH4) in the soil pore water of calcareous fens under three different water management regimes (re-wetted, deeply and moderately drained). Pore water was collected weekly or biweekly (April 2004 to April 2006) at depths between 10 and 150 cm.

The main results obtained were: (1) DIC (94–280 mg C l−1) was the main C-component. (2) POC and DOC concentrations in the pore water (14–125 mg C l−1 vs. 41–95 mg C l−1) were pari passu. (3) Dissolved CH4 was the smallest C component (0.005–0.9 mg C l−1). Interestingly, about 30% of the POM particles were colonized by microbes indicating that they are active in the internal C turnover. Certainly, both POC and DOC fractions are essential components of the C budget of peatlands. Furthermore, dissolved CO2 in all forms of DIC appears to be an important part of peatland C-balance.

Final-revised paper