Impacts of climate change on pedunculate oak (Quercus robur L.) and Phytophthora activity in north and central Europe

Sammanfattning: A climate change will affect the forests around the globe; there may be competitions for available resources that are needed for growth and dispersal. Europe is supposed to be more sensitive and may experience a greater influence than many other regions. As an additional effect of climate change extreme weather events will be more frequent e.g. drought and extreme precipitation that will cause flooding. The future weather and climate may affect pedunculate oak ([i]Quercus robur[/i]) both by weakening and strengthening. Drought and flooding may induce a higher susceptibility among trees to pathogens such as [i]Phytophthora[/i]due to stress. A higher temperature may extend the growing season and in interaction with good moisture supply and CO₂, carbon assimilation for growth might increase. Pedunculate oak, however, seem rather tolerant to a climate change and its additional effects, tough, in events of infection by [i]Phytophthora[/i]after a period of stress, the outcome might be more severe than if infected when not stressed. The oak may be declining but compared to other trees e.g. beech ([i]Fagus syvaltica[/i]), it may not be that severe. It seems as if beech is more susceptible to both climatic factors and [i]Phytophthora[/i]and might be more threatened in the long run, which might imply on a greater distribution of oaks.