A protocol for high-quality sectioning for tree-ring anatomy

Marina V Fonti ¹ Georg von Arx ¹ Maryline Harroue ² Loïc Schneider ¹ Daniel Nieveregelt ¹ Jesper Björklund ¹ Rashit Hantemirov ³ Vladimir Kukarskih ³ Cyrille Barthélémy Karl Rathgeber ² Nadja-Tamara Studer ¹ Patrick Fonti ^1*

• ¹ Landscape Dynamics, Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), Birmensdorf, Switzerland
• ² Université de Lorraine, Nancy, Lorraine, France
• ³ Institute of Plant and Animal Ecology, Ekaterinburg, Russia

Quantitative wood anatomy (QWA), which involves measuring wood cell anatomical characteristics commonly on dated tree rings, is becoming increasingly important within plant sciences and ecology. This approach is particularly valuable for studies that require processing a large number of samples, such as those aimed at millennial-long climatic reconstructions.However, the field faces significant challenges, including the absence of a publicly available comprehensive protocol for efficiently and uniformly producing high-quality wood thin sections for QWA along dated tree-ring series. This issue is especially critical for more brittle subfossil wood, in addition to fresh material from living trees.Our manuscript addresses these challenges by providing a detailed protocol for producing thin anatomical sections of wood and digital images, specifically tailored for long chronologies of treering anatomy with an emphasis on conifer wood. The protocol includes step-by-step procedures for sample preparation, sectioning, and imaging, ensuring consistent and high-quality results. By offering this well-tried-and-tested protocol, we aim to facilitate reproducibility and accuracy in wood anatomical studies, ultimately advancing research in this field. It aims to serve as a reference for researchers and laboratories engaged in similar work, promoting standardized practices and enhancing the reliability of QWA data.