[en] Tree-ring data provides essential insights into historical climate conditions and current ecosystem dynamics. Wood density measurements complement traditional tree-ring width series by extracting additional climatic information embedded within tree rings, with maximum latewood density serving as the gold standard for summer temperature reconstructions. However, the labor-intensive wood sample preparation required by conventional techniques is one of the main factors limiting the more widespread use of tree-ring densitometry. X-ray micro-computed tomography (XμCT) offers a novel, non-destructive, 3D densitometry technique that enables the simultaneous study of tree-ring width and wood density at high resolution and with minimal sample preparation. Despite its potential, the lack of a streamlined and time-efficient XμCT workflow has hindered its broader application in the past. Here we present a highly optimized XμCT pipeline aimed at large-scale tree-ring densitometry studies, capable of processing large amounts of increment cores with a low demand for human labor time (2.2–5.4 min per 35 cm sample length). Key parts include large and efficient sample holders (16–48 samples per scan), optimized and standardized scan settings (helical XμCT at 15, 30, and 60 μm voxel size), and three custom software packages (facilitating scan processing, ring indication, and cross-dating). Overall, this XμCT toolchain represents a significant leap forward in high-resolution tree-ring densitometry, enabling large-scale studies with a wide spatial extent, high replication, and/or long temporal range.
Disciplines :
Agriculture & agronomy Anatomy (cytology, histology, embryology...) & physiology Life sciences: Multidisciplinary, general & others
Author, co-author :
Verschuren, Louis; UGent-Woodlab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium ; UGent Centre for X-ray Tomography (UGCT), Ghent University, Ghent, Belgium ; Forest & Nature Lab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Melle, Belgium
Matskovsky, Vladimir; UGent-Woodlab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium ; UGent Centre for X-ray Tomography (UGCT), Ghent University, Ghent, Belgium
Boone, Matthieu N.; UGent Centre for X-ray Tomography (UGCT), Ghent University, Ghent, Belgium ; UGent-Radiation Physics, Department of Physics and Astronomy, Ghent University, Ghent, Belgium
Van Hoorebeke, Luc; UGent Centre for X-ray Tomography (UGCT), Ghent University, Ghent, Belgium ; UGent-Radiation Physics, Department of Physics and Astronomy, Ghent University, Ghent, Belgium
Van Acker, Joris; UGent-Woodlab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium ; UGent Centre for X-ray Tomography (UGCT), Ghent University, Ghent, Belgium
De Mil, Tom ; Université de Liège - ULiège > TERRA Research Centre > Gestion des ressources forestières
Trouet, Valerie; Laboratory of Tree Ring Research, University of Arizona, Tucson, United States
Pearson, Charlotte; Laboratory of Tree Ring Research, University of Arizona, Tucson, United States
De Bolle, Jorden; UGent Centre for X-ray Tomography (UGCT), Ghent University, Ghent, Belgium ; Deptartment of Solid State Sciences - CoCooN research group, Faculty of Sciences, Ghent University, Ghent, Belgium
Gheyle, Toon; UGent-Woodlab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium ; UGent Centre for X-ray Tomography (UGCT), Ghent University, Ghent, Belgium
Van den Bulcke, Jan; UGent-Woodlab, Department of Environment, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium ; UGent Centre for X-ray Tomography (UGCT), Ghent University, Ghent, Belgium
Language :
English
Title :
X-ray micro-CT pipeline for large-scale tree-ring densitometry studies
We acknowledge financial support from the Special Research Fund (BOF) for the UGCT Core Facility (BOF.COR.2022.008), the IOF for project FaCT F2021/IOF-Equip/021, and the Research Foundation\u2014Flanders (FWO) for the ACTREAL (G019521N) and XyloDynaCT (G00972ON) projects. We would like to thank Pierre Kibleur for the help with Arion. We are grateful to Stijn Willen, Yves Israel, Pieter Tack, Iv\u00E1n Josipovic, and Rudi Hoeben for technical and IT support. De Bolle J. Verschuren L. Van den Bulcke J. Boone M.N. Correction for the heel effect in helical \u03BCCT scans for accurate densitometry. Precision Engineering. [Under Review].
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