Catchment export of base cations : Improved mineral dissolution kinetics influence the role of water transit time
(2020) In Soil 6(1). p.231-244- Abstract
Soil mineral weathering is one of the major sources of base cations (BC), which play a dual role in forest ecosystems: they function as plant nutrients and buffer against the acidification of catchment runoff. On a long-term basis, soil weathering rates determine the highest sustainable forest productivity that does not cause acidification. It is believed that the hydrologic residence time plays a key role in determining the weathering rates at the landscape scale. The PROFILE weathering model has been used for almost 30 years to calculate weathering rates in the rooting zone of forest soils. However, the mineral dissolution equations in PROFILE are not adapted for the saturated zone, and employing these equations at the catchment scale... (More)
Soil mineral weathering is one of the major sources of base cations (BC), which play a dual role in forest ecosystems: they function as plant nutrients and buffer against the acidification of catchment runoff. On a long-term basis, soil weathering rates determine the highest sustainable forest productivity that does not cause acidification. It is believed that the hydrologic residence time plays a key role in determining the weathering rates at the landscape scale. The PROFILE weathering model has been used for almost 30 years to calculate weathering rates in the rooting zone of forest soils. However, the mineral dissolution equations in PROFILE are not adapted for the saturated zone, and employing these equations at the catchment scale results in a significant overprediction of base cation release rates to surface waters. In this study, we use a revised set of PROFILE equations which, among other features, include retardation due to silica concentrations. Relationships between the water transit time (WTT) and soil water concentrations were derived for each base cation, by simulating the soil water chemistry along a one-dimensional flow path, using the mineralogy from a glacial till soil. We show how the revised PROFILE equations are able to reproduce patterns in BC and silica concentrations as well as BC ratios (<span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M1" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Ca</mi><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>+</mo></mrow></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"48pt" heightCombining double low line"15pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"616b45de561f1e58f6ff0e2723b0fd15"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00001.svg" widthCombining double low line"48pt" heightCombining double low line"15pt" srcCombining double low line"soil-6-231-2020-ie00001.png"/></svg:svg></span></span>, <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M2" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Mg</mi><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>+</mo></mrow></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"49pt" heightCombining double low line"15pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"9cd18c3c6611eafb0f3a57584fa24b3f"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00002.svg" widthCombining double low line"49pt" heightCombining double low line"15pt" srcCombining double low line"soil-6-231-2020-ie00002.png"/></svg:svg></span></span> and <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M3" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Na</mi><mo>+</mo></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"44pt" heightCombining double low line"14pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"3fe7b69e656531fb4f615dcc4b75d667"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00003.svg" widthCombining double low line"44pt" heightCombining double low line"14pt" srcCombining double low line"soil-6-231-2020-ie00003.png"/></svg:svg></span></span>) that are observed in the soil water profiles and catchment runoff. In contrast to the original set of PROFILE equations, the revised set of equations could reproduce the fact that increasing WTT led to a decreasing <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M4" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Na</mi><mo>+</mo></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"44pt" heightCombining double low line"14pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"81a67bd2d63f6f499222325ebe2945cd"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00004.svg" widthCombining double low line"44pt" heightCombining double low line"14pt" srcCombining double low line"soil-6-231-2020-ie00004.png"/></svg:svg></span></span> ratio and increasing <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M5" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Ca</mi><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>+</mo></mrow></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"48pt" heightCombining double low line"15pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"6389b140e878165a412f4c0ea429f631"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00005.svg" widthCombining double low line"48pt" heightCombining double low line"15pt" srcCombining double low line"soil-6-231-2020-ie00005.png"/></svg:svg></span></span> and <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M6" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Mg</mi><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>+</mo></mrow></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"49pt" heightCombining double low line"15pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"3184b15065e7254f69639a69a9b19eb7"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00006.svg" widthCombining double low line"49pt" heightCombining double low line"15pt" srcCombining double low line"soil-6-231-2020-ie00006.png"/></svg:svg></span></span> ratios. Furthermore, the total release of base cations from a hillslope was calculated using a mixing model, where water with different WTTs was mixed according to an externally modeled WTT distribution. The revised set of equations gave a 50 % lower base cation release (0.23 eq m<span classCombining double low line"inline-formula">-2</span> yr<span classCombining double low line"inline-formula">-1</span>) than the original PROFILE equations and are in better agreement with mass balance calculations of weathering rates. Thus, the results from this study demonstrate that the revised mineral dissolution equations for PROFILE are a major step forward in modeling weathering rates at the catchment scale.
(Less)
- author
- Erlandsson Lampa, Martin LU ; Sverdrup, Harald U. LU ; Bishop, Kevin H. ; Belyazid, Salim LU ; Ameli, Ali and J. Köhler, Stephan
- organization
- publishing date
- 2020
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Soil
- volume
- 6
- issue
- 1
- pages
- 14 pages
- publisher
- Copernicus GmbH
- external identifiers
-
- scopus:85085956089
- ISSN
- 2199-3971
- DOI
- 10.5194/soil-6-231-2020
- language
- English
- LU publication?
- yes
- id
- 8a175352-bfd4-429d-9b18-409cb5d36ef8
- date added to LUP
- 2020-07-03 10:38:45
- date last changed
- 2022-04-18 23:20:31
@article{8a175352-bfd4-429d-9b18-409cb5d36ef8,
abstract = {{<p>Soil mineral weathering is one of the major sources of base cations (BC), which play a dual role in forest ecosystems: they function as plant nutrients and buffer against the acidification of catchment runoff. On a long-term basis, soil weathering rates determine the highest sustainable forest productivity that does not cause acidification. It is believed that the hydrologic residence time plays a key role in determining the weathering rates at the landscape scale. The PROFILE weathering model has been used for almost 30 years to calculate weathering rates in the rooting zone of forest soils. However, the mineral dissolution equations in PROFILE are not adapted for the saturated zone, and employing these equations at the catchment scale results in a significant overprediction of base cation release rates to surface waters. In this study, we use a revised set of PROFILE equations which, among other features, include retardation due to silica concentrations. Relationships between the water transit time (WTT) and soil water concentrations were derived for each base cation, by simulating the soil water chemistry along a one-dimensional flow path, using the mineralogy from a glacial till soil. We show how the revised PROFILE equations are able to reproduce patterns in BC and silica concentrations as well as BC ratios (<span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M1" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Ca</mi><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>+</mo></mrow></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"48pt" heightCombining double low line"15pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"616b45de561f1e58f6ff0e2723b0fd15"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00001.svg" widthCombining double low line"48pt" heightCombining double low line"15pt" srcCombining double low line"soil-6-231-2020-ie00001.png"/></svg:svg></span></span>, <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M2" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Mg</mi><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>+</mo></mrow></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"49pt" heightCombining double low line"15pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"9cd18c3c6611eafb0f3a57584fa24b3f"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00002.svg" widthCombining double low line"49pt" heightCombining double low line"15pt" srcCombining double low line"soil-6-231-2020-ie00002.png"/></svg:svg></span></span> and <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M3" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Na</mi><mo>+</mo></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"44pt" heightCombining double low line"14pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"3fe7b69e656531fb4f615dcc4b75d667"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00003.svg" widthCombining double low line"44pt" heightCombining double low line"14pt" srcCombining double low line"soil-6-231-2020-ie00003.png"/></svg:svg></span></span>) that are observed in the soil water profiles and catchment runoff. In contrast to the original set of PROFILE equations, the revised set of equations could reproduce the fact that increasing WTT led to a decreasing <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M4" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Na</mi><mo>+</mo></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"44pt" heightCombining double low line"14pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"81a67bd2d63f6f499222325ebe2945cd"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00004.svg" widthCombining double low line"44pt" heightCombining double low line"14pt" srcCombining double low line"soil-6-231-2020-ie00004.png"/></svg:svg></span></span> ratio and increasing <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M5" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Ca</mi><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>+</mo></mrow></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"48pt" heightCombining double low line"15pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"6389b140e878165a412f4c0ea429f631"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00005.svg" widthCombining double low line"48pt" heightCombining double low line"15pt" srcCombining double low line"soil-6-231-2020-ie00005.png"/></svg:svg></span></span> and <span classCombining double low line"inline-formula"><math xmlnsCombining double low line"http://www.w3.org/1998/Math/MathML" idCombining double low line"M6" displayCombining double low line"inline" overflowCombining double low line"scroll" dspmathCombining double low line"mathml"><mrow classCombining double low line"chem"><msup><mi mathvariantCombining double low line"normal">Mg</mi><mrow><mn mathvariantCombining double low line"normal">2</mn><mo>+</mo></mrow></msup><mo>/</mo><mi mathvariantCombining double low line"normal">BC</mi></mrow></math><span><svg:svg xmlns:svgCombining double low line"http://www.w3.org/2000/svg" widthCombining double low line"49pt" heightCombining double low line"15pt" classCombining double low line"svg-formula" dspmathCombining double low line"mathimg" md5hashCombining double low line"3184b15065e7254f69639a69a9b19eb7"><svg:image xmlns:xlinkCombining double low line"http://www.w3.org/1999/xlink" xlink:hrefCombining double low line"soil-6-231-2020-ie00006.svg" widthCombining double low line"49pt" heightCombining double low line"15pt" srcCombining double low line"soil-6-231-2020-ie00006.png"/></svg:svg></span></span> ratios. Furthermore, the total release of base cations from a hillslope was calculated using a mixing model, where water with different WTTs was mixed according to an externally modeled WTT distribution. The revised set of equations gave a 50&thinsp;% lower base cation release (0.23&thinsp;eq&thinsp;m<span classCombining double low line"inline-formula">-2</span>&thinsp;yr<span classCombining double low line"inline-formula">-1</span>) than the original PROFILE equations and are in better agreement with mass balance calculations of weathering rates. Thus, the results from this study demonstrate that the revised mineral dissolution equations for PROFILE are a major step forward in modeling weathering rates at the catchment scale.</p>}},
author = {{Erlandsson Lampa, Martin and Sverdrup, Harald U. and Bishop, Kevin H. and Belyazid, Salim and Ameli, Ali and J. Köhler, Stephan}},
issn = {{2199-3971}},
language = {{eng}},
number = {{1}},
pages = {{231--244}},
publisher = {{Copernicus GmbH}},
series = {{Soil}},
title = {{Catchment export of base cations : Improved mineral dissolution kinetics influence the role of water transit time}},
url = {{http://dx.doi.org/10.5194/soil-6-231-2020}},
doi = {{10.5194/soil-6-231-2020}},
volume = {{6}},
year = {{2020}},
}