Tree growth and water deficit in a planted mixed forest in Germany

Ing. Joana Camps Clot

Master's thesis

Abstract:

Droughts, wildfires or invasive insect outbreaks are some of the consequences of global warming, resulting in irreversible impacts on forest ecosystems. At tree species level, climate change effects remain largely unexplored. Mixed forests contribute to essential ecosystem services and provide more structural and species diversity than single-species forests. This study aims to evaluate the response of planted trees in the biodiversity experiment BIOTREE in Kaltenborn, Germany. I focus on four major central European tree species: European beech (Fagus sylvatica), Norway spruce (Picea abies), common oak (Quercus robur), and Douglas fir (Pseudotsuga menziesii). Each species was examined in monoculture as well as two-, three- and four-species mixtures. Stem growth and tree water deficit were analysed and compared for each case (in forest monocultures and species mixtures). Data for the thesis was collected from dendrometers and processed using linear and generalized additive models. The study found that monocultures had the fastest growth but also were the most sensitive to tree water deficit. However, it was conducted in an exceptionally favorable growing season. Even though monocultures have shown higher radius growth, mixed-species forests could be essential to enhance productivity and ecosystem resilience under climate change.

Keywords

climate change, dendrometers, planted forest, tree water deficit, BIOTREE, tree diversity

Language used: English

Date on which the thesis was submitted / produced: 31. 3. 2022

Thesis defence

• Supervisor: doc. Ing. Radim Matula, Ph.D.

Czech University of Life Sciences Prague

Faculty of Forestry and Wood Sciences

Master programme:
Nature Conservation