Climate change will massively affect beech trees
In 2004 and 2005, two teams of researchers published two key studies on the future of beech. One predicted a rather grim future for this species due to climate change. The other warned against scaremongering and attested to the beech's high adaptability. Researchers at the Swiss Federal Institute for Forest, Snow and Landscape Research WSL have now closely examined both studies using new data. They have concluded that the gloomy forecast will probably come true.
The future of beech trees in Europe looks bleak. Climate change will hit them hard. This is the conclusion of researchers at the Swiss Federal Institute for Forest, Snow and Landscape Research WSL. «Beech will not only lose its dominance and area in marginal sites, where it already does not find optimal conditions, but also in large parts of its Central European range,» says lead author of the study and WSL researcher Arthur Gessler. The tree will suffer in particular from the increasingly extreme dry years. «Drought can cause partial crown death, which often leads to the death of the tree the following year,» says Gessler.
The new study, «Back to the future - A new look at the prospects for beech after 20 years of research and advancing climate change», is based on two publications from 2004 and 2005, which came to divergent conclusions: While one of the teams predicted a severe threat to beech by the end of the 21st century, even in the core of its current range, the other did not see this danger – or only in areas already at risk of drought today – and warned of unsettling public and private forest owners.
Better data
«We now know much more than we did then about the effects of climate change on the vitality, growth, stress tolerance and competitiveness of beech trees, and we can therefore make more accurate predictions about their future potential,» says Arthur Gessler. «With this new knowledge, we were able to thoroughly re-examine the previous studies.»
Not only has the data situation improved considerably. The effects of climate change on beech forests (and forests in general) are now much more tangible today than twenty years ago and are no longer just the subject of scientific controversy.
«The extreme years of 2018, 2019, 2020, 2022 and, in some cases, 2023 have left visible, massive damage to the trees, which hints at future developments,» comments Gessler. In concrete terms, this means that the trees will no longer be able to regenerate well and will be very vulnerable to extreme events, which could lead to large-scale dieback and then local extinction of the species.
High diversity helps
The extent to which beech will be affected by the end of the century, and in which locations, will depend on the course of climate change and thus ultimately on the success of measures to reduce global CO2 emissions. «From today's perspective, however, it is clear that beech will suffer even if CO2 emissions are significantly reduced, i.e. under a rather optimistic climate change scenario,» says Gessler.
For this reason, Gessler believes that the forestry industry must prepare itself for fundamental changes. «To prepare forests for the future, drought- and heat-tolerant tree species such as oak should be introduced into the stands», says Gessler. A high diversity of structures and tree species, but also genetic diversity in beech, could help. In the worst case – even if the beech were to suffer massive drought damage – drought-resistant tree species would survive and thus at least prevent a total failure of the forest.
