FIRE AND AGE STRUCTURE OF SCOTS PINE AND NORWAY SPRUCE IN NORTHERN SWEDEN DURING THE PAST 700 YEARS

The performance of Pinus sylvestris L. and Picea abies (L.) Karst has been studied in relation to the fire regime from the 1200s up to present in an old-growth boreal forest area. The J-shaped age distribution of pine during the study period, suggests a stationary pattern in the landscape. The spruce age structure (from the 1600s onwards) also points towards a J-shape, although with slight deviations. No significant changes in total pine or spruce regeneration occurred in response to the significantly prolonged fire cycle (from 187 to 371 yr) around 1870. This break in the fire cycle might possibly have a climatic background.