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Updated: Jul 16, 2026
09:16
Methods of Soil Resampling to Monitor Changes in the Chemical Concentrations of Forest Soils
Published on: November 25, 2016
Characterizing the redox status in three different forested wetlands with geochemical data
Christine Alewell1, Sonja Paul, Gunnar Lischeid
1Environmental Geosciences, University of Basel, Bernoullistr. 30, CH-4056 Basel, Schwitzerland. christine.alewell@unibas.ch
Environmental Science & Technology
|January 30, 2007
Summary
Wetland biogeochemistry, especially sulfur, nitrogen, and iron cycling, is complex. Redox processes show high heterogeneity, challenging simple sequential reduction models at small scales but suggesting potential for macroscale modeling.
Area of Science:
- Environmental Science
- Geochemistry
- Ecology
Background:
- Wetland biogeochemistry and redox processes are poorly understood, impacting global change.
- Understanding source-sink functions for sulfur, nitrogen, and iron is crucial.
Purpose of the Study:
- Investigate redox processes in three forested wetlands.
- Analyze biogeochemical cycling of sulfur, nitrogen, and iron.
- Evaluate the applicability of sequential reduction models.
Main Methods:
- Stable sulfur isotope analysis.
- Geochemical analysis of soil and groundwater (iron, nitrate, sulfate, oxygen).
- Field investigation across varying wetland saturation and vegetation.
Main Results:
- Significant nitrate, sulfate, and iron reduction rates observed.
- High spatial and temporal heterogeneity in redox processes.
- No clear sequential reduction chain at micro/mesoscales due to simultaneous processes.
Conclusions:
- Sequential reduction models are not ideal for micro/mesoscale wetland redox dynamics.
- Simultaneous redox processes and high heterogeneity complicate modeling.
- Potential for macroscale modeling exists with extensive data.
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