Consequences of forest landscape changes for the availability of winter pastures to reindeer (Rangifer tarandus tarandus) from 1953 to 2003 in Kuusamo, northeast Finland

摘要

Using aerial photographs, we examined the changes in the forest matrix from 1953 to 2003 in the Oulanka National Park and commercial forests in the northern part of the municipality of Kuusamo. The changes concerned the potential winter grazing grounds available to the existing reindeer population. The main changes in the commercial forests took place between 1953 and 1977, during which time the mean forest-patch size shrank by 65%, and the number of patches increased by 78%. From 1953 to 2003, the total area of epiphytic lichens and ground-lichen pastures decreased by 48.6%. The area of ground-lichen pastures decreased by 20%, and the area of common hair grass pastures doubled. The forest matrix transition in the commercial forests changed not only the spatial configuration and areas of different pasture patches, but also the grazing pressure at the remaining pasture sites. In the national park, the changes in grazing pressure were related only to the changes in numbers of reindeer. In general, the conditions of reindeer pastures are a result of interaction between different land-use components.