Xylometrics Lab

Infrastructure

The laboratory’s work spans both foundational xylometric approaches—such as displaced water methods (see Björklund et al., 2021)—and modern microdensitometric techniques, including high- and low-resolution Blue Intensity as well as detailed wood-anatomical analyses of cell dimensions and structure (see Björklund et al., 2019).

The laboratory is located in Natrium at the University of Gothenburg and maintains a close collaboration with the Gothenburg University Laboratory for Dendrochronology (GULD). Xylometrics Lab is equipped with modern infrastructure for sample preparation, including microtomes and paraffin embedding, as well as advanced image analysis based on artificial intelligence, enabling automated and reproducible extraction of anatomical data.

Current research focuses on understanding why tree-ring-based climate reconstructions often show pronounced differences between the Northern and Southern Hemispheres, while climate models generally indicate a more coherent pattern of temperature variability. A particular emphasis is placed on identifying methodological causes of these discrepancies and on investigating why different microdensitometric approaches sometimes yield divergent results, as well as how such differences can be reconciled within a unified analytical framework.

An additional core objective of Xylometrics Lab is to develop and disseminate cost-effective methods for generating high-quality climate information from tree rings. This work aims to facilitate broader global participation in climate research, including by research environments with limited technical and financial resources.

Members and Networks

Xylometrics Lab is a recently established laboratory founded by Dr Jesper Björklund and Dr Kristina Seftigen. The lab is closely linked to the Gothenburg University Laboratory for Dendrochronology (GULD), both scientifically and spatially, as the two units are housed in adjacent facilities.

Laboratory members

• Jesper Björklund, Director, with a strong focus on wood density and climate reconstructions
• Kristina Seftigen, Deputy Director and expert in tree-ring-based hydroclimate reconstructions
• Tinghai Ou, Research Engineer and expert in climate modelling
• Petter Stridbeck, PhD student focusing on methods development
• Anne Jaeppelt, PhD student focusing on temperature reconstructions for Australasia
• Giancarlo Genovese, PhD student focusing on quantitative wood anatomy
• Oskar Elmqvist, MSc student
• Joakim Lindh Staxgård, BSc student
• Lyra Stigestad Sivertsen, BSc student

The laboratory will soon be expanded with:

• a technician responsible for wood sample preparation and analysis
• a postdoctoral researcher specializing in quantitative wood anatomy and climate reconstructions

Collaboration

Xylometrics Lab has a very close collaboration with the DendroSciences group at the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), which is internationally leading in wood-anatomical research. Both Jesper Björklund and Kristina Seftigen began their research careers at WSL in 2014 as newly graduated PhD researchers. Today, WSL and Xylometrics Lab share several joint research projects, primarily in collaboration with Dr Georg von Arx head of the DendroSciences group at WSL.

The laboratory also collaborates closely with Ghent University’s Centre for X-ray Tomography (UGCT), which drives methodological development in X-ray tomography of tree rings. As part of ongoing advances in microdensitometry and quantitative wood anatomy, this collaboration seeks to better understand similarities and differences in results obtained using different analytical techniques.

Within the framework of the recently launched ERC project BOREAUSTRALIS, Xylometrics Lab also collaborates with research groups in Switzerland, the United States, Argentina, Australia, New Zealand, and China.

Peer-reviewed publications highlights

• Fonti, M. V., von Arx, G., Harroue, M., Schneider, L., Nievergelt, D., Björklund, J., ... & Fonti, P. (2025). A protocol for high-quality sectioning for tree-ring anatomy. Frontiers in Plant Science, 16, 1505389.
• Seftigen, K., von Arx, G., Fonti, M. V., & Björklund, J. (2025). Benchmarking Blue Intensity from drought limited Pinus sylvestris using tree-ring anatomy. Dendrochronologia, 92, 126367.
• Björklund, J., Seftigen, K., Kaczka, R. J., Rydval, M., & Wilson, R. (2024). A definition and standardised terminology for Blue Intensity from Conifers. Dendrochronologia, 85, 126200.
• Björklund, J., Seftigen, K, Stoffel, M., Fonti, M. V., Kottlow, S., Frank D. C., Esper, J., Fonti, P., Goosse, H., Grudd, H., Gunnarson, B. E., Nievergelt, D., Pellizzari, E., Carrer, M. & von Arx, G. (2023). Fennoscandian tree-ring anatomy shows a warmer modern than medieval climate. Nature, 620 (7972), 97-103.
• Seftigen, K., Fonti, M. V., Luckman, B., Rydval, M., Stridbeck, P., von Arx, G., Wilson, R., and Björklund, J.: Prospects for dendroanatomy in paleoclimatology – a case study on Picea engelmannii from the Canadian Rockies, Clim. Past, 18, 1151–1168, https://doi.org/10.5194/cp-18-1151-2022, 2022.
• Björklund, J., von Arx, G., Nievergelt, D., Wilson, R., Van den Bulcke, J., Günther, B., ... & Frank, D. (2019). Scientific merits and analytical challenges of tree‐ring densitometry. Reviews of Geophysics, 57(4), 1224-1264.

Popular sciene publications highlights 

• Björklund, J. (2025). Inga ringar utan celler. In: Linderholm (Ed.), Fantastiska Ringar.
  Svenska Sällskapet för Antropologi och Geografi, YMER.
• Seftigen, K. (2025). Att ringa in torkan. In: Linderholm (Ed.), Fantastiska Ringar.
  Svenska Sällskapet för Antropologi och Geografi, YMER.
• Björklund, J., von Arx, G. (2023). Wood-anatomy data refine the record of climate in Northern Europe. RESEARCH BRIEFINGS Nature doi: https://doi.org/10.1038/d41586-023-02010-z