Drought-Induced Alterations in Topsoil Characteristics and Acidification Risks in a Floodplain Ecosystem: A Case Study from Tam Nong District, Vietnam

Authors

  • Nguyen Thi My Huyen

    University of Science, Ho Chi Minh City 700000, Viet Nam

    Vietnam National University-Ho Chi Minh City, HCM City 700000, Viet Nam
  • Do Ngoc Thanh

    University of Science, Ho Chi Minh City 700000, Viet Nam

    Vietnam National University-Ho Chi Minh City, HCM City 700000, Viet Nam
  • Nguyen Vinh Tung

    University of Science, Ho Chi Minh City 700000, Viet Nam

    Vietnam National University-Ho Chi Minh City, HCM City 700000, Viet Nam
  • Dang Truong An

    University of Science, Ho Chi Minh City 700000, Viet Nam

    Vietnam National University-Ho Chi Minh City, HCM City 700000, Viet Nam
  • Nguyen Thi To Ngan

    University of Science, Ho Chi Minh City 700000, Viet Nam

    Vietnam National University-Ho Chi Minh City, HCM City 700000, Viet Nam
  • Lieu Kim Phuong

    Institute of Life Sciences, Vietnam Academy of Science and Technology, Ho Chi Minh City 700000, Viet Nam

DOI:

https://doi.org/10.30564/re.v7i5.10338
Received: 4 June 2025 | Revised: 12 June 2025 | Accepted: 1 September 2025 | Published Online: 17 November 2025

Abstract

The Tam Nong district, a flood-prone, low-lying area within Dong Thap province, Vietnam, benefits from nutrient-rich sediments deposited by the upper Mekong River. Its soils, predominantly thionic Fluvisols with smaller areas of Gleyic Acrisols and Histic Fluvisols, are vital for regional agriculture. This study investigates the impact of severe drought events, specifically in 2016 and 2024, on the physicochemical properties of topsoil (0–25 cm). A comparative analysis between drought-affected (2024) conditions and pre-drought/less severe drought (2016 reference) conditions revealed significant, statistically supported detrimental alterations. Drought conditions promoted increased soil acidification, evidenced by reduced pHKCl values across all soil types (p < 0.05) and elevated total sulfur (SO₄²⁻) concentrations. Conversely, organic matter (OM) content, overall fertility, and cation exchange capacity (CEC) generally declined, indicating acid sulfate-driven degradation and diminished fertility. Fine-textured thionic Fluvisols and Epi-prothothionic Histic Fluvisols exhibited greater vulnerability to drought-induced degradation compared to medium-textured Gleyic Acrisols. Thionic Fluvisols underwent the most severe acid sulfate degradation, transitioning from slightly acidic to increasingly acidic states, with pHKCl values frequently dropping below 4.0. Gleyic Acrisols were less affected, maintaining moderate OM and CEC. Histic Fluvisols displayed notable acidification despite their high OM content. These findings underscore the progressive nature of drought-induced soil degradation, posing increasing threats to agricultural sustainability and farmer livelihoods in this vulnerable floodplain ecosystem, and highlight the urgent need for tailored soil management strategies.

Keywords:

Soil Acidification; Drought; Fluvisol; Vietnamese Mekong Delta; Degradation

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How to Cite

Huyen, N. T. M., Thanh, D. N., Tung, N. V., An, D. T., Ngan, N. T. T., & Phuong, L. K. (2025). Drought-Induced Alterations in Topsoil Characteristics and Acidification Risks in a Floodplain Ecosystem: A Case Study from Tam Nong District, Vietnam. Research in Ecology, 7(5), 143–154. https://doi.org/10.30564/re.v7i5.10338

Issue

Vol.7, Iss.5 (December 2025)(in progress)

Article Type

Article

License

Copyright © 2025 Nguyen Thi My Huyen, Do Ngoc Thanh, Nguyen Vinh Tung, Dang Truong An, Nguyen Thi To Ngan, Lieu Kim Phuong

Creative Commons License

This is an open access article under the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) License.

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