Journal ArticleDOI
Evaluation of an Advanced Benchtop Micro-Computed Tomography System for Quantifying Porosities and Pore-Size Distributions of Two Brazilian Oxisols
TLDR
In this article, the authors evaluated the impact of sample size and scanning resolution on CT-derived porosities and pore-size distributions of two Brazilian Oxisols from segmented computed tomography (CT)-data.Abstract:
Recent advances in benchtop Micro-Computed Tomography (Micro-CT) provided the motivation to thoroughly evaluate and optimize scanning, image reconstruction/segmentation and pore space analysis capabilities of a SkyScan 1172 Micro-CT system and associated SkyScan Analyzer software package (SkyScan, Belgium). To demonstrate applicability to soil research the project was focused on determination of porosities and pore-size distributions of two Brazilian Oxisols from segmented computed tomography (CT)-data. Effects of metal filters and various acquisition parameters (e.g., total rotation, rotation step, and radiograph frame averaging) on image quality and acquisition time were evaluated. Impacts of sample size and scanning resolution on CT-derived porosities and pore-size distributions were illustrated. Best image quality was achieved when an aluminum/copper filter (0.5/0.04 mm thickness) was positioned between sample and x-ray detector, the sample was rotated 360° in 0.3° steps and the number of averaged projections per rotation step was larger than 15. As with all other CT systems there was a tradeoff between maximum observable sample volume and achievable resolution. Even for soil samples scanned at the highest considered resolution of 3.7 μm (1.0 μm is the maximum achievable resolution) it was apparent that CT-derived porosities vastly underestimated physically measured apparent porosity values. In addition, it was shown that dense mineral particles can be discriminated from slightly attenuating elements and minerals. While image acquisition and reconstruction yielded excellent grayscale CT-data, the supplied software lacked advanced image segmentation algorithms and morphometric pore space analysis capabilities.read more
Citations
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Journal ArticleDOI
Applications of X‐ray computed tomography for examining biophysical interactions and structural development in soil systems: a review
Jonathan R. Helliwell,Craig J. Sturrock,Kathryn M Grayling,Saoirse R. Tracy,Richard J. Flavel,Iain M. Young,William R. Whalley,Sacha J. Mooney +7 more
TL;DR: A review of the application of one such technique, X-ray computed tomography (CT), for studies of undisturbed soil systems, focusing on research during the last 10 years in particular, is presented in this paper.
Journal ArticleDOI
Emergent Properties of Microbial Activity in Heterogeneous Soil Microenvironments: Different Research Approaches Are Slowly Converging, Yet Major Challenges Remain.
Philippe C. Baveye,Wilfred Otten,Alexandra Kravchenko,María Balseiro-Romero,María Balseiro-Romero,Eléonore Beckers,Maha Chalhoub,Christophe Darnault,Thilo Eickhorst,Patricia Garnier,Simona M. Hapca,Serkan Kiranyaz,Olivier Monga,Carsten W. Mueller,Naoise Nunan,Valérie Pot,Steffen Schlüter,Hannes Schmidt,Hans-Jörg Vogel +18 more
TL;DR: The objective of the present article is to review progress achieved to date in the significant research program that has ensued, namely the quantification and modeling of the physical-, (bio)chemical-, and microbiological properties of soils, and the integration of these different perspectives into a unified theory.
Journal ArticleDOI
Effect of scanning and image reconstruction settings in X-ray computed microtomography on quality and segmentation of 3D soil images
Alasdair N. Houston,Sonja Schmidt,Ana M. Tarquis,Wilfred Otten,Philippe C. Baveye,Philippe C. Baveye,Simona M. Hapca +6 more
TL;DR: Investigation of the effect of scanning resolution and reconstruction settings such as noise reduction and 32-bit to 8-bit mapping interval on the 3D X-ray CT imaging of soil structure and the impact on the performance of thresholding methods suggests that the acquisition and reconstruction parameters investigated significantly affect the quality of soil images, and the subsequent thresholding process.
Journal ArticleDOI
Impact of Long-Term Fertilization Practice on Soil Structure Evolution
Muhammad Naveed,Per Moldrup,Hans-Jörg Vogel,Mathieu Lamandé,Dorthe Wildenschild,Markus Tuller,Lis Wollesen de Jonge +6 more
TL;DR: In this paper, the authors characterized soil structure development and evolution in six plots that were amended with varying amounts of animal manure (AM) and NPK fertilizer over a period of 106 years in a long-term fertilization experiment in Bad Lauchstadt, Germany.
Journal ArticleDOI
Evaluation of X-ray computed tomography for quantifying macroporosity of loamy pasture soils
TL;DR: In this paper, the feasibility of X-ray computed tomography (CT) for determining macroporosity in dairy pasture soils and to assess the effects of sample volume (both within and between cores of varying sizes) and locations (i.e. site and soil depth) on measures of porosity.
References
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