» Articles » PMID: 37753209

Consider the Anoxic Microsite: Acknowledging and Appreciating Spatiotemporal Redox Heterogeneity in Soils and Sediments

Overview
Date 2023 Sep 27
PMID 37753209
Authors
Affiliations
Soon will be listed here.
Abstract

Reduction-oxidation (redox) reactions underlie essentially all biogeochemical cycles. Like most soil properties and processes, redox is spatiotemporally heterogeneous. However, unlike other soil features, redox heterogeneity has yet to be incorporated into mainstream conceptualizations of soil biogeochemistry. Anoxic microsites, the defining feature of redox heterogeneity in bulk oxic soils and sediments, are zones of oxygen depletion in otherwise oxic environments. In this review, we suggest that anoxic microsites represent a critical component of soil function and that appreciating anoxic microsites promises to advance our understanding of soil and sediment biogeochemistry. In sections 1 and 2, we define anoxic microsites and highlight their dynamic properties, specifically anoxic microsite distribution, redox gradient magnitude, and temporality. In section 3, we describe the influence of anoxic microsites on several key elemental cycles, organic carbon, nitrogen, iron, manganese, and sulfur. In section 4, we evaluate methods for identifying and characterizing anoxic microsites, and in section 5, we highlight past and current approaches to modeling anoxic microsites. Finally, in section 6, we suggest steps for incorporating anoxic microsites and redox heterogeneities more broadly into our understanding of soils and sediments.

Citing Articles

Decoupling microbial iron reduction from anoxic microsite formation in oxic sediments: a microscale investigation through microfluidic models.

Ceriotti G, Bosco-Santos A, Borisov S, Berg J Front Microbiol. 2025; 16:1504111.

PMID: 39935649 PMC: 11811102. DOI: 10.3389/fmicb.2025.1504111.


Adaptation of Archaeal Communities to Summer Hypoxia in the Sediment of Bohai Sea.

Guo X, Li Y, Song G, Zhao L, Wang J Ecol Evol. 2025; 15(1):e70768.

PMID: 39781248 PMC: 11707553. DOI: 10.1002/ece3.70768.


Geochemical Decoupling of Iron and Zinc during Transformation of Zn-Bearing Ferrihydrite in Reducing Sediments.

Lefebvre P, Grigg A, Kretzschmar R Environ Sci Technol. 2024; 58(45):20224-20234.

PMID: 39491537 PMC: 11562722. DOI: 10.1021/acs.est.4c09261.


Methane cycling in temperate forests.

Wigley K, Armstrong C, Smaill S, Reid N, Kiely L, Wakelin S Carbon Balance Manag. 2024; 19(1):37.

PMID: 39438363 PMC: 11515791. DOI: 10.1186/s13021-024-00283-z.


Influences of topography on nitrate export from forested watersheds on Yakushima Island, a Natural World Heritage site.

Shinozuka K, Nagafuchi O, Nakazawa K, Tsunogai U, Nakagawa F, Tetsuka K RSC Adv. 2024; 14(41):29860-29872.

PMID: 39301230 PMC: 11411419. DOI: 10.1039/d4ra04168b.


References
1.
Bak F, Nybroe O, Zheng B, Badawi N, Hao X, Nicolaisen M . Preferential flow paths shape the structure of bacterial communities in a clayey till depth profile. FEMS Microbiol Ecol. 2019; 95(3). PMC: 6397044. DOI: 10.1093/femsec/fiz008. View

2.
Vieweg M, Trauth N, Fleckenstein J, Schmidt C . Robust optode-based method for measuring in situ oxygen profiles in gravelly streambeds. Environ Sci Technol. 2013; 47(17):9858-65. DOI: 10.1021/es401040w. View

3.
Kumar N, Noel V, Planer-Friedrich B, Besold J, Lezama-Pacheco J, Bargar J . Redox Heterogeneities Promote Thioarsenate Formation and Release into Groundwater from Low Arsenic Sediments. Environ Sci Technol. 2020; 54(6):3237-3244. DOI: 10.1021/acs.est.9b06502. View

4.
Keiluweit M, Wanzek T, Kleber M, Nico P, Fendorf S . Anaerobic microsites have an unaccounted role in soil carbon stabilization. Nat Commun. 2017; 8(1):1771. PMC: 5701132. DOI: 10.1038/s41467-017-01406-6. View

5.
Pett-Ridge J, Petersen D, Nuccio E, Firestone M . Influence of oxic/anoxic fluctuations on ammonia oxidizers and nitrification potential in a wet tropical soil. FEMS Microbiol Ecol. 2013; 85(1):179-94. DOI: 10.1111/1574-6941.12111. View