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Updated: Jul 15, 2025
11:43
Dissolved Solute Sampling Across an Oxic-Anoxic Soil-Water Interface Using Microdialysis Profilers
Published on: March 24, 2023
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Consider the Anoxic Microsite: Acknowledging and Appreciating Spatiotemporal Redox Heterogeneity in Soils and
Emily M Lacroix1,2, Meret Aeppli3, Kristin Boye4
1Institut des Dynamiques de la Surface Terrestre (IDYST), Université de Lausanne, 1015 Lausanne, Switzerland.
ACS Earth & Space Chemistry
|September 27, 2023
Summary
Anoxic microsites, zones of oxygen depletion in soils, are crucial for biogeochemical cycles. Understanding these redox heterogeneities advances soil science and environmental processes.
Area of Science:
- Soil Science
- Biogeochemistry
- Environmental Science
Background:
- Reduction-oxidation (redox) reactions are fundamental to biogeochemical cycles.
- Soil redox conditions exhibit significant spatial and temporal heterogeneity.
- Redox heterogeneity, particularly anoxic microsites, is underrepresented in soil biogeochemistry models.
Purpose of the Study:
- To define anoxic microsites and their dynamic properties.
- To review the influence of anoxic microsites on elemental cycles (C, N, Fe, Mn, S).
- To evaluate methods for identifying, characterizing, and modeling anoxic microsites.
Main Methods:
- Literature review and synthesis.
- Conceptual framework development for anoxic microsites.
- Evaluation of existing and novel methodologies.
Main Results:
- Anoxic microsites are dynamic and significantly impact soil function.
- These microsites influence the cycling of carbon, nitrogen, iron, manganese, and sulfur.
- Current methods for detection and modeling are evolving.
Conclusions:
- Anoxic microsites are critical to soil and sediment biogeochemistry.
- Incorporating redox heterogeneity into models is essential for accurate predictions.
- Further research on anoxic microsites will advance soil science.
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