Project summary

The amount of carbon sequestered in forests is proportional to trends in stem biomass, which therefore represent an important variable potentially entering to models forecasting dynamics of atmospheric carbon content. However, we lack information on predictive skills of models focused on tree stem growth at reasonable time scales of climate change, that is from few to ten decades corresponding to assumed warming roughly between 1 to 4 °C. To bridge this gap, the new doctoral researcher will use space for time substitution approach and calibrate a range of stem growth models at relatively cold/wet sites and test/verify these calibrated models at relatively warmer/drier sites on elevation and precipitation gradient, simulating in this way the effect of warming. Doctoral researcher will employ climatically-determined models of low to medium complexity ranging from linear models to simple process-based models relying on ecophysiological parameters at daily resolution. To interpret match or mismatch between observed and predicted growth, detailed growth observations using long tree-ring width series, data from dendrometers and xylogenesis will be performed. Data will be collected at three spatial scales. First, at landscape scale using our long-term monitoring plots, second, at scale of core area of European temperate forests with the use of TreeDataClim database (www.treedataclim.cz), third, at scale of temperate forests biome with the use of database data. Doctoral researcher will profit from availability of fully equipped dendrochronological laboratory, network of monitoring plots and accessible dendrochronological data collections. Process-based modelling part of the study will be co-supervised by Jan Tumajer. The fully funded PhD project (including salary, fieldwork expenses, equipment, and consumables) is part of the new interdepartmental research excellence program “Georisks” (JAK, 2024-2028). The successful candidate will join the structured, international, and interdisciplinary four-year PhD program of the Department of Physical Geography and Geoecology. We seek a candidate with experiences in dendrochronological methods, strong background in R programming, and willing to participate in field collection of data from dendrometers, tree-rings, xylogenesis, and stem water potential measurements.

Selected publications of the research group related to the project

Mašek, J., Tumajer, J., Lange, J., Vejpustková, M., Kašpar, J., Šamonil, P., Chuman, T., Kolář, T., Rybníček, M., Jeníček, M., Vašíčková, I., Čada, V., Kaczka, R., Rydval, M., Svoboda, M., Nedělčev, O., Hais, M., and Treml, V. (2024): Shifting climatic responses of tree rings and NDVI along environmental gradients. Science of The Total Environment 908, 168275. DOI: 10.1016/j.scitotenv.2023.168275.

Tumajer, J., Begović, K., Čada, V., Jenicek, M., Lange, J., Mašek, J., Kaczka, R.J., Rydval, M., Svoboda, M., Vlček, L., Treml, V. (2023): Ecological and methodological drivers of non-stationarity in tree growth response to climate. Global Change Biology 29(2): 462–476. DOI: 10.1111/gcb.16470

Treml V., Masek J., Tumajer J., Rydval M., Cada V., Ledvinka O., Svoboda M. (2022). Trends in climatically driven extreme growth reductions of Picea abies and Pinus sylvestris in Central Europe. Global Change Biology 28(2): 557-570. https://doi.org/10.1111/gcb.15922

Tumajer, J., Kašpar, J., Kuželová, H., Shishov, V. V., Tychkov, I. I., Popkova, M. I., Vaganov, E. A., & Treml, V. (2021). Forward Modeling Reveals Multidecadal Trends in Cambial Kinetics and Phenology at Treeline. Frontiers in Plant Science, 12, 613646. https://doi.org/10.3389/fpls.2021.613643