Impact of climate change on old-growth forest

Our world is going through a period of environmental changes caused by human activities in recent decades. This includes the introduction of exotic species and large-scale changes in land use, carbon emissions into the biosphere and forest harvesting or burning. In the fight against environmental change and global warming, forests play a major role. Climate change is causing great concern worldwide for forest dieback (forest mortality) and reduced forest growth due to drought phenomena. This is accompanied by high carbon costs due to reductions in gross old-growth production and net ecosystem exchange. Changes in atmospheric circulation patterns may play a determining role in the functionality and survival of temperate deciduous forests in the future. In addition, European forests are also affected by a series of storms, widespread forest fires, rapidly spreading bark beetle infestations, and various other pest and disease outbreaks. Such disturbances events will shift in terms of frequency and intensity due to climate change. This results in alteration of forest ecosystems and their services, including human amenities. As climate warming accelerates, the limits of species tolerance to long-term extreme events remain uncertain.

More details about the impact of climate change on old-growth forests

Forests are complex systems that network with thousands of species and possess important ecological functions such as microclimate regulation, enabling water retention, and thermodynamic efficiency. External factors on top of global warming can accelerate and amplify the decline of forests. Therefore, forest management should be evaluated more thoroughly and the concepts and findings of conservation biology, ecosystem theory and systems ecology should be taken into account. The limited information on the interaction between soil properties, drought and microbiomes, including soil pathogens; needs more attention. What is already clear nowadays is that fungal communities have an essential contribution to plant growth and survival and ecosystem function.
European forests have an adaptive capacity where trees will recover when extreme events occur, but with the increase and more frequent extreme events taking place, current forests may reach the limits of this adaptive capacity. At some sites, we might have to opt for a management with tree species adapted to changing site characteristics to ensure the persistence of the forest. Although they will certainly undergo changes due to the changing circumstances, old-growth forests are likely to be highly resilient. Such ecosystems have to be protected and restored to ensure a sustainable future.

 Pettit, J. L., Pettit, J. M., Janda, P., Rydval, M., Čada, V., Schurman, J. S., … & Svoboda, M. (2021). Both Cyclone‐induced and convective storms drive disturbance patterns in European primary beech forests. Journal of Geophysical Research: Atmospheres, 126(7), e2020JD033929.