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Mathieu Lamandé

Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic

Research output: Contribution to conferenceConference abstract for conferenceResearch

Standard

Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic. / Lamandé, Mathieu; Schjønning, Per.

2016. Abstract from Quantifying the Role of Biophysical Processes in Soil Structure Dynamics, Zurich, Switzerland.

Research output: Contribution to conferenceConference abstract for conferenceResearch

Harvard

Lamandé, M & Schjønning, P 2016, 'Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic', Quantifying the Role of Biophysical Processes in Soil Structure Dynamics, Zurich, Switzerland, 14/04/2016 - 15/04/2016.

APA

Lamandé, M., & Schjønning, P. (2016). Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic. Abstract from Quantifying the Role of Biophysical Processes in Soil Structure Dynamics, Zurich, Switzerland.

CBE

Lamandé M, Schjønning P. 2016. Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic. Abstract from Quantifying the Role of Biophysical Processes in Soil Structure Dynamics, Zurich, Switzerland.

MLA

Lamandé, Mathieu and Per Schjønning Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic. Quantifying the Role of Biophysical Processes in Soil Structure Dynamics, 14 Apr 2016, Zurich, Switzerland, Conference abstract for conference, 2016. 1 p.

Vancouver

Lamandé M, Schjønning P. Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic. 2016. Abstract from Quantifying the Role of Biophysical Processes in Soil Structure Dynamics, Zurich, Switzerland.

Author

Lamandé, Mathieu ; Schjønning, Per. / Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic. Abstract from Quantifying the Role of Biophysical Processes in Soil Structure Dynamics, Zurich, Switzerland.1 p.

Bibtex

@conference{32c65f1603354dab9b164b5887bf5cfa,
title = "Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic",
abstract = "Compaction of the subsoil can only be alleviated by natural processes. The objective of this study was to evaluate the long-term effect of compaction on the pore system at 0.35 m depth of a heavy clay soil naturally subjected to drying and wetting, and to freezing and thawing, and biological activity in Finland. The compaction treatment was inflicted 29 years prior to investigation and included four passes with a tractor-trailer combination with wheel loads up to 4.8 Mg and inflation pressures of 700 kPa. Gas diffusion and air permeability measurements were combined with pycnometer-estimated air-filled pore volumes. The largest macropores were characterized on three-dimensional images acquired using an x-ray medical CT scanner. We wanted to evaluate, to what extent the compaction affected soil pore geometries and volumes. The combination of diffusive and advective gas transport characteristics was expected to enhance the ability to deduce how the soil pore system was affected. This included advective air flow measurements at a range of pneumatic pressure drops. Compaction at 0.35 m depth was persistent 29 years after the compaction event. Compaction diminished the diameter of vertical macropores that served as arterial pores, while the volume and role of marginal pores branching from the arterial pores were diminished. Compacted soil had the significantly lowest volume of blocked pores not in contact to the surrounding atmosphere. For this clay-holding soil, the long-term compaction effect is interpreted as a serious reduction of the aeration potential of the bulk soil matrix in between the vertical, arterial pores. Our data indicate a high degree of anisotropy of (clay-holding) subsoil pores, and that state-of-the art models are not able to describe soil diffusivity for such soils. We suggest air permeability measurements at a range of pressure drops in combination with a regression method for estimating Darcy air permeability. Care should be taken in using the specific permeability as an indication of pore tortuosity in cases, where the dimensions of the soil pores are significantly different.",
author = "Mathieu Lamand{\'e} and Per Schj{\o}nning",
year = "2016",
language = "English",
note = "null ; Conference date: 14-04-2016 Through 15-04-2016",

}

RIS

TY - ABST

T1 - Subsoil compaction of a Vertic Cambisol persists three decades after wheel traffic

AU - Lamandé, Mathieu

AU - Schjønning, Per

PY - 2016

Y1 - 2016

N2 - Compaction of the subsoil can only be alleviated by natural processes. The objective of this study was to evaluate the long-term effect of compaction on the pore system at 0.35 m depth of a heavy clay soil naturally subjected to drying and wetting, and to freezing and thawing, and biological activity in Finland. The compaction treatment was inflicted 29 years prior to investigation and included four passes with a tractor-trailer combination with wheel loads up to 4.8 Mg and inflation pressures of 700 kPa. Gas diffusion and air permeability measurements were combined with pycnometer-estimated air-filled pore volumes. The largest macropores were characterized on three-dimensional images acquired using an x-ray medical CT scanner. We wanted to evaluate, to what extent the compaction affected soil pore geometries and volumes. The combination of diffusive and advective gas transport characteristics was expected to enhance the ability to deduce how the soil pore system was affected. This included advective air flow measurements at a range of pneumatic pressure drops. Compaction at 0.35 m depth was persistent 29 years after the compaction event. Compaction diminished the diameter of vertical macropores that served as arterial pores, while the volume and role of marginal pores branching from the arterial pores were diminished. Compacted soil had the significantly lowest volume of blocked pores not in contact to the surrounding atmosphere. For this clay-holding soil, the long-term compaction effect is interpreted as a serious reduction of the aeration potential of the bulk soil matrix in between the vertical, arterial pores. Our data indicate a high degree of anisotropy of (clay-holding) subsoil pores, and that state-of-the art models are not able to describe soil diffusivity for such soils. We suggest air permeability measurements at a range of pressure drops in combination with a regression method for estimating Darcy air permeability. Care should be taken in using the specific permeability as an indication of pore tortuosity in cases, where the dimensions of the soil pores are significantly different.

AB - Compaction of the subsoil can only be alleviated by natural processes. The objective of this study was to evaluate the long-term effect of compaction on the pore system at 0.35 m depth of a heavy clay soil naturally subjected to drying and wetting, and to freezing and thawing, and biological activity in Finland. The compaction treatment was inflicted 29 years prior to investigation and included four passes with a tractor-trailer combination with wheel loads up to 4.8 Mg and inflation pressures of 700 kPa. Gas diffusion and air permeability measurements were combined with pycnometer-estimated air-filled pore volumes. The largest macropores were characterized on three-dimensional images acquired using an x-ray medical CT scanner. We wanted to evaluate, to what extent the compaction affected soil pore geometries and volumes. The combination of diffusive and advective gas transport characteristics was expected to enhance the ability to deduce how the soil pore system was affected. This included advective air flow measurements at a range of pneumatic pressure drops. Compaction at 0.35 m depth was persistent 29 years after the compaction event. Compaction diminished the diameter of vertical macropores that served as arterial pores, while the volume and role of marginal pores branching from the arterial pores were diminished. Compacted soil had the significantly lowest volume of blocked pores not in contact to the surrounding atmosphere. For this clay-holding soil, the long-term compaction effect is interpreted as a serious reduction of the aeration potential of the bulk soil matrix in between the vertical, arterial pores. Our data indicate a high degree of anisotropy of (clay-holding) subsoil pores, and that state-of-the art models are not able to describe soil diffusivity for such soils. We suggest air permeability measurements at a range of pressure drops in combination with a regression method for estimating Darcy air permeability. Care should be taken in using the specific permeability as an indication of pore tortuosity in cases, where the dimensions of the soil pores are significantly different.

M3 - Conference abstract for conference

Y2 - 14 April 2016 through 15 April 2016

ER -