Research projects

DivLand: Landscape and Biodiversity Research Center

The Landscape and Biodiversity Research Center aims to develop and monitor indicators of biodiversity and landscape changes. In particular, our goal is to analyze trends in stem biomass of the main forest tree species in the Czech Republic. The trends of stem biomass are calculated based on a network of tree-ring chronologies and allometric equations.

Principal investigator: Dušan Romportl (Václav Treml)

Grantor: Technology Agency of the Czech Republic (TAČR)

Duration: 2021-2026

Grant number: TAČR SS02030018

Using forward modelling to unravel the complex climatic control on intra-annual tree growth at cold distribution margins

There is growing evidence that temperature control on tree growth can vary across space and over time at treelines, and moisture availability can be a seasonally important limiting factor at otherwise cold-limited sites. Studies at the intra-annual (wood cell) level can help unravel these complex climate-growth responses, but long time series of wood formation data are rarely available. We will bridge this gap by combining 1) quantitative wood anatomy and 2) process-based models of wood formation to systematically assess the climate-driven intra-annual dynamics of tree growth at representative polar and alpine treeline sites in Eurasia and North America. Analyses will be based on a dataset of annually resolved tree-ring widths, intra-annually resolved xylem anatomical traits (e.g., cell number, lumen area), and (bi-) weekly xylogenesis observation data.

Principal investigator: Jelena Lange

Grantor: Czech Science Foundation (GAČR)

Duration: 2022-2024

Grant number: GAČR 22-26519S

Tree-ring database as a tool for evidence and prediction of response of main forest species to climate change

We are developing a tree-ring database called TreeDataClim. The database consists of hundreds of tree-ring site records with tree-ring series of more than 20 000 trees. The database is linked to a web GIS. Tree-ring records help determine the recent climatic limitation of tree growth with respect to regions, elevation, and site characteristics. Process-based climate-driven growth models are calibrated on tree-ring chronologies, and the derived parameters are then used to apply the model to climate scenario data. We produce maps of recent and future climatic constraints on tree growth that are published via a web GIS service.

Principal investigator: Václav Treml

Grantor: Technology Agency of the Czech Republic (TAČR)

Duration: 2021-2024

Grant number: TAČR SS0310134

Does rising CO2 concentration decrease the sensitivity of European temperate conifers to drought?

We ask whether increasing water-use efficiency of temperate trees affects their growth response to climate. To answer this question, we build chronologies of tree-ring width and water-use efficiency that representatively cover the upper and lower range margins of Picea abies and Pinus sylvestris in Central Europe. We focus on stationarity of climate-growth responses, trends in extreme growth reductions, and factors behind the increase in water-use efficiency.

Principal investigator: Václav Treml

Grantor: Czech Science Foundation (GAČR)

Duration: 2019-2022

Grant number: GA19-13807S

Monitoring of treeline stands in NPR Praděd, Jeseníky Mts

Goal: Coming soon

Principal investigator: Václav Treml

Grantor: AOPK CR through EkoGroup s.r.o.

Duration: 2018-2022

Delineation of treeline ecotone and the analysis of treeline dynamics in the Krkonoše National Park

Goal: Coming soon

Principal investigator: Václav Treml

Grantor: OP ŽP, KRNAP administration

Duration: 2018-2021


Individual research fellowships

Using forward modelling to unravel the complex climatic control on intra-annual tree growth at cold distribution margins

This project addresses the question of how temperature and moisture availability interact in limiting intra-annual wood formation at generally cold-limited sites. For representative cold-limited sites across North America and Eurasia, a dataset of annually resolved tree-ring width series, (bi-) weekly xylogenesis observation data, and decades-long time series of xylem anatomical traits (e.g., cell lumen area, cell number) is compiled. Both linear and non-linear, processed based models are used to systematically assess intra-annual growth dynamics across study sites over the past decades.

Fellowship holder: Jelena Lange

Grantor: Alexander von Humboldt Foundation / Feodor Lynen Research Fellowship

Duration: 2022-2023

Drought record in tree rings of Scots pine and vegetation indices derived from Landsat satellite data – complementarity of data at landscape level

There is uncertainty about the factors that limit forest biomass production, particularly about how forest growth is limited by moisture availability. Tree-ring data provide a good measure of the effects of drought on biomass production, and by linking tree-ring data to vegetation indices derived from satellite scenes, we could be able to describe wood increment at the landscape scale. The goal of this project is to determine the relationship between tree-ring data and vegetation indices for Scots pine and Norway spruce in two areas in the Czech Republic, and to explain the differential response of stem and leaf biomass to drought based on topography and stand characteristics.

Fellowship holder: Jiří Mašek

Grantor: Charles University Science Foundation (GAUK)

Duration: 2020-2022

Grant number: GAUK 548120