Research

Summary of my research topics in 20 words

Based on the titles, abstracts, and keywords of my peer-reviewed publications (December 2025). https://www.freewordcloudgenerator.com/generatewordcloud 

Three categories of woody plant increase: (a) infilling of existing patches, (b) increased growth, and (c) an advancing shrubline/treeline. Adapted from Myers-Smith et al. (2011). 

Shrubs and trees are recolonising mountains in response to global change. How and why? 

In response to global change, an upward shift of the upper forest limit and increasing shrub encroachment are being observed in temperate mountain regions. Through my work, I aim to (i) describe the spatio-temporal dynamics of woody plant expansion and (ii) analyse the respective contributions of climate change and land-use change to these dynamics in order to disentangle their underlying drivers. To achieve this, I combine two complementary types of analysis conducted at different spatial scales.

At the biogeographical scale, I map habitats using satellite remote sensing, with a particular focus on shrublands, a land-cover type that is especially difficult to delineate. Vegetation indices, such as the Normalized Difference Vegetation Index (NDVI), are then used to quantify “greening”, defined as an increase in plant biomass over time. This approach enables the characterisation of vegetation patterns and dynamics across large spatial extents; however, its temporal depth is limited and the specific mechanisms underlying observed greening trends cannot be resolved in detail.

At finer spatial scales, I focus on case studies that allow a more precise and detailed analysis of shrub and forest dynamics over longer time periods and with higher temporal resolution. In particular, I rely on dendrochronological data to accurately reconstruct expansion processes, as well as on historical archival sources such as aerial photographs and cadastral records, which provide essential context on vegetation dynamics and land-use history. 

Does climate change favour or limit the growth of woody plants in mountains?

In cold environments such as temperate mountain regions, woody plant growth is generally constrained by temperature but depending on elevation, topography and species, it can be more complicated than that. Dendroecology, through the analysis of tree rings, enables the identification of climatic factors driving interannual variability in growth. My work focuses on (i) characterising the climatic drivers of mountain woody plant growth, (ii) assessing how the influence of these drivers has evolved in response to climate change, and (iii) identifying long-term growth trends using tree-ring width chronologies.

To investigate climate–growth relationships, I primarily analyse tree-ring widths, complemented by quantitative wood anatomy through the examination of intra-ring dendroanatomical parameters. With respect to climate data, I prioritise the use of local datasets and biologically meaningful variables and time windows; for example, the timing of snowmelt is used as a proxy for growing-season length. To evaluate temporal changes in climate–growth relationships, I examine the occurrence of divergence phenomena, defined as a reduction in growth sensitivity to climatic variables and shifts in the nature of climate–growth relationships over time, particularly through comparisons among distinct periods.

Beyond interannual variability, I also aim to disentangle long-term trends in tree growth. To this end, I rely on extensive dendrochronological sampling, which allows the construction of regional standardisation curves and age-class–specific analyses. These robust approaches make it possible to assess long-term growth trends while minimising the confounding effects of tree age inherent in dendrochronological series.