Retrospective land cover/land use change trajectories as drivers behind the local distribution and abundance patterns of oaks in south-western Finland
Käyhkö Niina; Skånes Helle
https://urn.fi/URN:NBN:fi-fe2021042720095
Tiivistelmä
Valuable cultural landscapes are challenging to sustain. They are
usually rare and reflect unique histories of nature–human interactions.
We have studied the influence of environmental factors on the present
distribution, age and abundance of oaks in a unique forest site in
south-western Finland. The Landscape Change Trajectory Analysis (LCTA)
approach was tested to improve management strategies at a local level.
We used geospatial analysis in GIS on existing data from a recent forest
inventory, a multi-temporal land cover/land use analysis, and a digital
elevation model. The results show that mature Pendunculate oaks (Quercus robur)
are restricted to the eastern parts of Ruissalo island and their
present abundance patterns can be linked with change trajectories as
opposed to physical conditions. While the prevailing strategy of strict
protection seems to lead to an increasing amount of dead wood, the lack
of management hampers the regeneration of oaks. We suggest four
principles for future management of these sites that could be applied
throughout the hemiboreal region of Europe with similar historical
development: (1) management regimes should be spatially explicit in
terms of land cover history instead of treating valuable oak biotopes as
one homogenous unit; (2) management units should be determined by
biotope dynamics and development rather than present status and
distribution; (3) management should allow strict protection of sites
with long duration of protection and high abundance of decaying oak wood
to support biodiversity; (4) alternative management regimes should be
introduced in sites with high potential for re-establishment of
light-abundant favourable conditions.
Kokoelmat
- Rinnakkaistallenteet [19207]