Fires and pests threaten 90% of Mediterranean forests

The years between 2001 and 2020 were an intense period in terms of wildfires, forest pests, and strong winds. Before the end of the 21st century, these environmental disturbances could double in Europe, warns a study led by researchers from the Technical University of Munich and published in the journal ScienceWith the participation of Catalan organizations, including the Centre for Ecological Research and Forestry Applications (CREAF), the Centre for Forest Science and Technology of Catalonia (CTFC), and the University of Girona, the research has determined that this is the future awaiting the European continent if greenhouse gas emissions are not significantly reduced. "The doubling of disturbance rates corresponds to the worst-case scenario, that is, if nothing is done to stop these emissions," explains CREAF researcher and co-author of the study, Josep Maria Espelta, who adds that, if they are limited, "the increase in disturbances could be contained." The research indicates that the disturbances that will increase the most are forest fires and insect infestations, while windstorms will increase more slightly. "Phenomena such as fires and infestations are determined by similar causes, such as the increase in temperature, and are therefore closely linked to climate change," Espelta points out. In this regard, the study specifies that the annual burned area in Europe could triple by the end of the century, making some episodes currently considered extreme commonplace. Meanwhile, the insects expected to see the greatest increase are wood-boring beetles. "Higher temperatures shorten their life cycles, allowing them to complete more than one per year, and also enabling them to reach areas that were previously colder," explains the expert. This series of increases makes the phenomenon even more alarming considering it follows a period of already high fire disturbances. "We are comparing it with data from a very high rate, which makes it relatively more worrying," warns Espelta.

The research has worked with the three climate scenarios determined by the Intergovernmental Panel on Climate Change (IPCC) and projected the evolution of forests from 2020 to 2100. According to the data, the Mediterranean region—which includes Catalonia—is among the most vulnerable areas, as nearly nine percent of its forests are susceptible to pests due to episodes of high warming. High temperatures, as the study details, weaken Mediterranean trees and favor pests such as bark beetles, which destroy the wood of the tree "to the point that it can die." At a European scale, fires and pests can lead to a reduction in old-growth forests, which are already scarce—representing 3% of the total area of ​​the Old Continent—while young forests, which have less capacity to absorb CO₂, increase. "It's a mechanism that accelerates this whole process, and that also represents a change at all levels of the European landscape," explains Espelta. The results were obtained assuming business-as-usual forest management practices. However, the researchers assert that adding climate change-adapted solutions will increase forest resilience: "We need to decarbonize society, and that means being less dependent on fossil fuels and more on clean energy." Espelta also emphasizes the importance of landscape management and promoting agroforestry mosaics. "We must become aware of these new scenarios and increase self-protection measures," concludes the CREAF researcher.