Advanced Analyses of Tree Physiological Time Series in R and PhytoSim

Increasing availability of tree physiological time series on tree growth and water use provide unique opportunities for exploring tree and forest function, health, and resilience to ongoing environmental changes. However, processing such time series data is challenging, due to data quantity and quality, varying time steps, labour-intensive data cleaning, and assumptions for converting raw measurements to physiologically meaningful quantities. To resolve such issues, software tools are continuously being developed, facilitating data pre- and post-processing in a fast, efficient and reproducible way.

Within this workshop we provide participants hands-on training on novel software tools: R packages to process dendrometer and sap flow data, and PhytoSim models to integrate data and unravel underlying mechanisms. Dendrometer functionalities include the option to align measurements to regular time intervals, remove outliers and correct for data-jumps. Additionally, parameters such as yearly growth or maximum daily shrinkage are provided. For sap flow data processing, we present functionalities for importing and homogenising raw measurements, conducting various data-processing approaches, calculating sap flux density and crown conductance, and their uncertainties. For the dendrometer-sap flow combination, we focus on turgor-driven growth and hydraulics.

Guided by example datasets, this interactive workshop presents a benchmark for dendrometer and sap flow data processing methods and facilitates greater potential for improving comparability between datasets. Participants should bring their own laptops with pre-installed copy of R and RStudio and/or PhytoSim. Data files and codes for this workshop will be made publicly available, so participants and those unable to attend will have access to these resources.

• Follow this link for a presentation introducing the workshop.
• Follow this link to view the course materials.

Organizer

• Richard L. Peters (Ghent University)

Co-organizers

• Christoforos Pappas (Centre d’étude de la forêt, Université du Québec à Montréal & Téluq)
• Roman Zweifel (Swiss Federal Institute for Forest, Snow and Landscape Research WSL; personal page)
• Kathy Steppe (Ghent University; personal page)
• Alexander Hurley (GFZ)