Modelling the future climatic suitability of plantation forest tree species

 

Climate change: Impacts on UK forests - Chapter 11
By Duncan Ray, Graham Pyatt and Mark Broadmeadow

Key findings

• Existing empirical yield models are unable to account for the effects of climate change and rising carbon dioxide concentration CO2.
• Mechanistic, process-based models can account for the effects of both rising CO2 and climate change; however, they are generally ‘data hungry’ and, although they are good at simulating relative changes to productivity, their ability to make absolute predictions of forest yield is limited.
• Knowledge-based modelling approaches such as Ecological Site Classification (ESC) are good in absolute terms because they are based on observed distributions of yield or presence, and require only climate and soil information in addition to the distribution data.
• The drawback of knowledge-based models is their inability to account for the predicted rise in CO2; they therefore represent worst case scenarios, in that the beneficial effects of rising CO2 to water use and yield are not taken into account.
• The application of the UKCIP98 scenarios in the ESC model results in a number of tentative predictions for UK plantation forest species as listed. These predictions show commercial suitability.
• • Sitka spruce will become more suitable across the cooler uplands of Scotland and northern England, and also the eastern side of Scotland; the Suitable area in parts of lowland England may become Unsuitable; the southwest peninsula and Wales should, at least, remain Suitable.
  • Corsican pine will become Very Suitable in eastern Scotland where it is currently Suitable, while growth rates will increase across southern England.
  • Douglas fir will remain, at least, Suitable across most of south and east England, and Very Suitable in the West Midlands and much of the southwest and east Wales; the climate is predicted to become more suitable for Douglas fir across the whole of Scotland, but particularly in the east.
  • Beech is likely to become Very Suitable across much of eastern Scotland, where it is currently marginally Suitable; in England, the areas where it is currently Suitable and Very Suitable are likely to contract northwards, and in areas of southern England, beech may no longer be Suitable as a timber crop. 
• The character and composition of native woodland ecosystems is also likely to change, possibly with the formation of new communities and sub-communities.

Next: Chapter 12 - Impacts on the distribution of plant species found in native beech woodland

Previous: Chapter 10 - Impacts of climate change on forest growth