Evolution of pH, redox potential and solute concentrations in soil and drainage water at a cultivated acid sulfate soil profile

Heidi Salo; Seija Virtanen; Hanne Laine-Kaulio; Harri Koivusalo; Diederik Jacques; Teemu Kokkonen

doi:10.1016/j.geoderma.2023.116559

Evolution of pH, redox potential and solute concentrations in soil and drainage water at a cultivated acid sulfate soil profile

Heidi Salo^*
, Seija Virtanen
, Hanne Laine-Kaulio
, Harri Koivusalo
, Diederik Jacques
, Teemu Kokkonen

^*Corresponding author for this work

Research output: Contribution to journal › Article › Scientific › peer-review

8 Citations (Scopus)

106 Downloads (Pure)

Abstract

Land drainage lowers the soil water table, which triggers enhanced oxidation of iron sulfide minerals in acid sulfate soils, causing acidification of fields and posing environmental hazards to aquatic ecosystems. The objective of this study was to develop a model for investigating the effects of oxidation of iron sulfide minerals and the cation exchange capacity (CEC) on the long-term evolution of pH, redox potential and solute concentrations in soil water and drain discharge. Two electron acceptors (oxygen and ferric iron) were included in the model. The model was implemented in the HP1 modeling platform (coupled HYDRUS-1D and PHREEQC-3) and applied to an acid sulfate soil profile of an agricultural field in Finland. The geochemical part of the model was tested against field observations. A comparison of different model versions showed that CEC had an essential role in mimicking the observed pH profile of soil. The drain discharge water quality was similar in the model versions both with and without CEC, but the buffering effect of CEC could be seen as lower iron concentrations. The oxidation of metastable iron sulfide minerals was three times faster than the oxidation of pyrite. Descriptions for the oxidation of both two minerals and for CEC were required to conduct long-term simulations that reproduce the observed geochemical state of a drained agricultural field. The HP1 modeling platform facilitated the testing of alternative chemical transformation processes of an AS soil profile in response to increased drainage efficiency after subsurface drainage installation.

Original language	English
Article number	116559
Number of pages	13
Journal	Geoderma
Volume	436
DOIs	https://doi.org/10.1016/j.geoderma.2023.116559
Publication status	Published - Aug 2023
MoE publication type	A1 Journal article-refereed

Funding

The Drainage Foundation sr is acknowledged for the funding. Part of the funding was provided by the Aalto University School of Engineering. We acknowledge Jyrki Nurminen and Antti Louhio for their help in conducting laboratory measurements. We acknowledge Tony Appelo for his guidance and insight with the PHREEQC-3 program. We acknowledge Maija Paasonen-Kivekäs for insights and comments on the study. The Drainage Foundation sr is acknowledged for the funding. Part of the funding was provided by the Aalto University School of Engineering. We acknowledge Jyrki Nurminen and Antti Louhio for their help in conducting laboratory measurements. We acknowledge Tony Appelo for his guidance and insight with the PHREEQC-3 program. We acknowledge Maija Paasonen-Kivekäs for insights and comments on the study.

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

SDG 15 Life on Land

Keywords

Acid sulfate soil
CEC
HP1 model
Oxidation of sulfides
Subsurface drainage

Access to Document

10.1016/j.geoderma.2023.116559Licence: CC BY

1-s2.0-S0016706123002367-mainFinal published version, 2.9 MBLicence: CC BY

Cite this

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title = "Evolution of pH, redox potential and solute concentrations in soil and drainage water at a cultivated acid sulfate soil profile",

abstract = "Land drainage lowers the soil water table, which triggers enhanced oxidation of iron sulfide minerals in acid sulfate soils, causing acidification of fields and posing environmental hazards to aquatic ecosystems. The objective of this study was to develop a model for investigating the effects of oxidation of iron sulfide minerals and the cation exchange capacity (CEC) on the long-term evolution of pH, redox potential and solute concentrations in soil water and drain discharge. Two electron acceptors (oxygen and ferric iron) were included in the model. The model was implemented in the HP1 modeling platform (coupled HYDRUS-1D and PHREEQC-3) and applied to an acid sulfate soil profile of an agricultural field in Finland. The geochemical part of the model was tested against field observations. A comparison of different model versions showed that CEC had an essential role in mimicking the observed pH profile of soil. The drain discharge water quality was similar in the model versions both with and without CEC, but the buffering effect of CEC could be seen as lower iron concentrations. The oxidation of metastable iron sulfide minerals was three times faster than the oxidation of pyrite. Descriptions for the oxidation of both two minerals and for CEC were required to conduct long-term simulations that reproduce the observed geochemical state of a drained agricultural field. The HP1 modeling platform facilitated the testing of alternative chemical transformation processes of an AS soil profile in response to increased drainage efficiency after subsurface drainage installation.",

keywords = "Acid sulfate soil, CEC, HP1 model, Oxidation of sulfides, Subsurface drainage",

author = "Heidi Salo and Seija Virtanen and Hanne Laine-Kaulio and Harri Koivusalo and Diederik Jacques and Teemu Kokkonen",

note = "Funding Information: The Drainage Foundation sr is acknowledged for the funding. Part of the funding was provided by the Aalto University School of Engineering. We acknowledge Jyrki Nurminen and Antti Louhio for their help in conducting laboratory measurements. We acknowledge Tony Appelo for his guidance and insight with the PHREEQC-3 program. We acknowledge Maija Paasonen-Kivek{\"a}s for insights and comments on the study. Funding Information: The Drainage Foundation sr is acknowledged for the funding. Part of the funding was provided by the Aalto University School of Engineering. We acknowledge Jyrki Nurminen and Antti Louhio for their help in conducting laboratory measurements. We acknowledge Tony Appelo for his guidance and insight with the PHREEQC-3 program. We acknowledge Maija Paasonen-Kivek{\"a}s for insights and comments on the study. Publisher Copyright: {\textcopyright} 2023 The Author(s)",

year = "2023",

month = aug,

doi = "10.1016/j.geoderma.2023.116559",

language = "English",

volume = "436",

journal = "Geoderma",

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T1 - Evolution of pH, redox potential and solute concentrations in soil and drainage water at a cultivated acid sulfate soil profile

AU - Salo, Heidi

AU - Virtanen, Seija

AU - Laine-Kaulio, Hanne

AU - Koivusalo, Harri

AU - Jacques, Diederik

AU - Kokkonen, Teemu

N1 - Funding Information: The Drainage Foundation sr is acknowledged for the funding. Part of the funding was provided by the Aalto University School of Engineering. We acknowledge Jyrki Nurminen and Antti Louhio for their help in conducting laboratory measurements. We acknowledge Tony Appelo for his guidance and insight with the PHREEQC-3 program. We acknowledge Maija Paasonen-Kivekäs for insights and comments on the study. Funding Information: The Drainage Foundation sr is acknowledged for the funding. Part of the funding was provided by the Aalto University School of Engineering. We acknowledge Jyrki Nurminen and Antti Louhio for their help in conducting laboratory measurements. We acknowledge Tony Appelo for his guidance and insight with the PHREEQC-3 program. We acknowledge Maija Paasonen-Kivekäs for insights and comments on the study. Publisher Copyright: © 2023 The Author(s)

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N2 - Land drainage lowers the soil water table, which triggers enhanced oxidation of iron sulfide minerals in acid sulfate soils, causing acidification of fields and posing environmental hazards to aquatic ecosystems. The objective of this study was to develop a model for investigating the effects of oxidation of iron sulfide minerals and the cation exchange capacity (CEC) on the long-term evolution of pH, redox potential and solute concentrations in soil water and drain discharge. Two electron acceptors (oxygen and ferric iron) were included in the model. The model was implemented in the HP1 modeling platform (coupled HYDRUS-1D and PHREEQC-3) and applied to an acid sulfate soil profile of an agricultural field in Finland. The geochemical part of the model was tested against field observations. A comparison of different model versions showed that CEC had an essential role in mimicking the observed pH profile of soil. The drain discharge water quality was similar in the model versions both with and without CEC, but the buffering effect of CEC could be seen as lower iron concentrations. The oxidation of metastable iron sulfide minerals was three times faster than the oxidation of pyrite. Descriptions for the oxidation of both two minerals and for CEC were required to conduct long-term simulations that reproduce the observed geochemical state of a drained agricultural field. The HP1 modeling platform facilitated the testing of alternative chemical transformation processes of an AS soil profile in response to increased drainage efficiency after subsurface drainage installation.

AB - Land drainage lowers the soil water table, which triggers enhanced oxidation of iron sulfide minerals in acid sulfate soils, causing acidification of fields and posing environmental hazards to aquatic ecosystems. The objective of this study was to develop a model for investigating the effects of oxidation of iron sulfide minerals and the cation exchange capacity (CEC) on the long-term evolution of pH, redox potential and solute concentrations in soil water and drain discharge. Two electron acceptors (oxygen and ferric iron) were included in the model. The model was implemented in the HP1 modeling platform (coupled HYDRUS-1D and PHREEQC-3) and applied to an acid sulfate soil profile of an agricultural field in Finland. The geochemical part of the model was tested against field observations. A comparison of different model versions showed that CEC had an essential role in mimicking the observed pH profile of soil. The drain discharge water quality was similar in the model versions both with and without CEC, but the buffering effect of CEC could be seen as lower iron concentrations. The oxidation of metastable iron sulfide minerals was three times faster than the oxidation of pyrite. Descriptions for the oxidation of both two minerals and for CEC were required to conduct long-term simulations that reproduce the observed geochemical state of a drained agricultural field. The HP1 modeling platform facilitated the testing of alternative chemical transformation processes of an AS soil profile in response to increased drainage efficiency after subsurface drainage installation.

KW - Acid sulfate soil

KW - CEC

KW - HP1 model

KW - Oxidation of sulfides

KW - Subsurface drainage

UR - https://www.scopus.com/pages/publications/85163052537

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DO - 10.1016/j.geoderma.2023.116559

M3 - Article

AN - SCOPUS:85163052537

SN - 0016-7061

VL - 436

JO - Geoderma

JF - Geoderma

M1 - 116559

ER -

Evolution of pH, redox potential and solute concentrations in soil and drainage water at a cultivated acid sulfate soil profile

Abstract

Funding

UN SDGs

Keywords

Access to Document

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Studies from Aalto University Reveal New Findings on Agriculture (Evolution of Ph, Redox Potential and Solute Concentrations In Soil and Drainage Water At a Cultivated Acid Sulfate Soil Profile)

Cite this

Evolution of pH, redox potential and solute concentrations in soil and drainage water at a cultivated acid sulfate soil profile

Abstract

Funding

UN SDGs

Keywords

Access to Document

Other files and links

Fingerprint

Press/Media

Studies from Aalto University Reveal New Findings on Agriculture (Evolution of Ph, Redox Potential and Solute Concentrations In Soil and Drainage Water At a Cultivated Acid Sulfate Soil Profile)

Cite this