When speculating on what is going to happen to our forests in an uncertain future, it is hard to generalize. Impacts on tree growth, regeneration and mortality due to climate change and other factors (e.g., forest management, disturbances) are usually quantified with scenario modelling at course, large-scale. However, given the heterogeneity of European mountain forests, the effects of climate change on ecosystem services at the local-scale seems to be highly variable. Read more what researchers from ETH Zürich in collaboration with other European partners found.

The importance of mountain forests as source of ecosystem services

Mountain forest ecosystems deliver a large number of ecosystem goods and services. For example, they are a great source of timber and other wood/non-wood products, they protect the land against erosion and human settlements from natural hazards. Mountain forests also store a vast amount of carbon and are biodiversity hotspots. Living most of our daily lives in lowland urban areas we may not think too much about this, but it is estimated that about half of the global human population depends – directly or indirectly – on services delivered by mountain forests. It is therefore essential to assess whether multiple ecosystem services can be provided to human societies in the future. Given that climate is changing fast, the consideration of climate change in scientific assessments is a must! Let’s not forget that European forests are managed since centuries (check out this nice book about the history of European forests). Thus, changes in management regimes must be considered as well.

Simulations of forest dynamics

Researchers from ETH Zürich modelled forest dynamics with a climate-sensitive forest gap model in four mountain regions across Southern-Central Europe. Their main aim was to investigate how climate change and management may alter the provision of ecosystem services in the future. As part of their study, they also analysed trade-offs and synergies between different ecosystem services. The investigation was part of the large European FP7 project ARANGE (“Advanced multifunctional management of European mountain forest RANGEs”). The project officially ended in July 2015 with the scientific conference “Mountain Forest Management in a Changing World” (High Tatra Mountains) after three and a half years of collaborative work.

Main results

Scientists found contrasting results between the four investigated case study regions – Iberian Mountains, Western Alps, Eastern Alps and Dinaric Mountains. For example, in the Iberian Mountains their simulation results indicate that forest management, rather than climate change, is responsible for a reduction in carbon storage and biodiversity. On the contrary, in Western Alps changes in climatic regimes could induces large alterations in the supply of several ecosystem services, particularly under the most pessimistic future climate scenarios. In other areas (e.g., in the Slovenian Dinaric Mountains) climate change would strongly affect ecosystem services, albeit differently depending on elevation and stand conditions. This highlight the necessity to consider the heterogeneity of local climate and initial stand conditions when projecting regional-scale forest development, as well as including high-resolution management interventions.

Regarding trade-offs and synergies, they found that each relationship between two ecosystem services differs significantly depending on the case study region, and it is highly sensitive to changes in management regimes. Climate change is also a cause of alteration of the relationships between some ecosystem services, but its effect is not evident and consistent across all the regions. This confirms that management is a strong driver of forest dynamics in European mountains, and it can highly modify the future provision of ecosystem services (i.e., more than the direct effects of climate change!).

Implications for forest management

They concluded that management regimes should be regionally adapted for better supporting multiple ecosystem services in the future. This because there are large differences between mountain ranges across Europe and contrasting effects of climate change on forest stands along gradients of elevation and species composition. The most advantageous management scenario in terms of ecosystem services provision, however, clearly depends on the specific needs in the different regions.

Certainly, researchers have still work to do on this hot topic. More modelling studies at multiple spatial scale on the impacts of climate change, management and disturbance events on future ecosystem services would be more than welcome! Without generalizing too much, though.

Source: Mina M., Bugmann H., Cordonnier T., Irauschek F., Klopcic M., Pardos M., and Cailleret M. 2016. Future ecosystem services from European mountain forests under climate change. Journal of Applied Ecology (Early View). doi:10.1111/1365-2664.12772

Author of the post:

Marco Mina – Forest ecologist. PostDoc at the Swiss Federal Research Institute WSL. PhD in Forest Ecology at ETH Zürich, after graduating in Forestry and Environmental Science from Padua University. The focus of his research is on better understanding the impacts of climate change on forests and ecosystem services using process-based, statistical models and forest inventory data. He is also interested in dendroecology, silviculture and wood biomass production. Passionate traveller, nordic skier and homebrewer.