Articles | Volume 12, issue 2
https://doi.org/10.5194/soil-12-937-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/soil-12-937-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Short communication
| 
23 Sep 2026
Short communication |
| 23 Sep 2026
| 23 Sep 2026
Long-term storage of air-dried samples compromises water-extractable organic carbon as a soil health indicator
Swarnali Mahmood
CORRESPONDING AUTHOR
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
Franky Celestin
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
Diego Arruda Huggins de Sá Leitão
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
Ryan E. Champiny
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
Xinlin Wang
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
JoAnn B. Donald
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
Audrey Plauche
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
S. Carolina Córdova
Department of Agronomy and Horticulture, University of Nebraska-Lincoln, Lincoln, NE 68583, USA
Christine D. Sprunger
Department of Plant, Soil, and Microbial Sciences, W.K. Kellogg Biological Station, Michigan State University, Hickory Corners, MI 49060, USA
Gabriel Maltais-Landry
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
Yang Lin
Department of Soil, Water, and Ecosystem Sciences, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611, USA
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Short summary
Soil health tests often use sensitive indicators, but their reliability after long-term storage is unclear. Using air-dried archived soils from a cover crop experiment, we found that three years of storage nearly doubled water-extractable organic carbon. Similar water-extractable organic carbon patterns across different long-term agricultural experiment sites show that storage can distort concentrations, so archived samples should be interpreted with caution.
Soil health tests often use sensitive indicators, but their reliability after long-term storage...
