Articles | Volume 22, issue 7
https://doi.org/10.5194/bg-22-1745-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-1745-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Solubility characteristics of soil humic substances as a function of pH: mechanisms and biogeochemical perspectives
Xuemei Yang
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Institute of Ecology, College of Urban and Environmental Sciences, Peking University, Beijing, 100091, China
Jie Zhang
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
Mohammad Mohinuzzaman
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Department of Environmental Science and Disaster Management, Noakhali Science and Technology University, Noakhali, Bangladesh
H. Henry Teng
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
Nicola Senesi
Dip.to di Scienze del Suolo, della Pianta e degli Alimenti, Università degli Studi di Bari “Aldo Moro”, Via G. Amendola 165/A, 70126 Bari, Italy
Giorgio S. Senesi
CNR – Istituto per la Scienza e Tecnologia dei Plasmi (ISTP) – sede di Bari Via Amendola, 122/D, 70126 Bari, Italy
Jie Yuan
College of Resources and Environment, Xingtai University, Quanbei East Road 88, Qiaodong District, Xingtai City, Hebei Province, China
Yu Liu
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
Si-Liang Li
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
Xiaodong Li
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
Baoli Wang
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
Cong-Qiang Liu
CORRESPONDING AUTHOR
School of Earth System Science, Tianjin University, 92 Weijin Road, Tianjin 300072, China
Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Tianjin University, Tianjin 300072, China
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Short summary
The solubility characteristics of soil humic acids (HAs), fulvic acids (FAs), and protein-like substances (PLSs) at varying pH levels remain unclear. The key findings include the following: HA solubility increases with increasing pH and decreases with decreasing pH; HApH6 and HApH1 contribute to 39.1–49.2% and 3.1–24.1% of dissolved organic carbon, respectively; and HApH2, FA, and PLSs are highly soluble at acidic pHs and are transported by ambient water. These issues are crucial for sustainable soil management.
The solubility characteristics of soil humic acids (HAs), fulvic acids (FAs), and protein-like...
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