Landscapes Forest and Global Change - ESA - Escola Superior ...

M. Kolström et al. 2010. Is it possible to combine adaptation to climate change and maintaining of forest biodiversity
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regeneration of suitable species increase spatial heterogeneity (e.g. Spiecker 2003). A dense forest
road network is the prerequisite to small-scale, structurally diverse thinning and harvesting practices
under adaptive management. In complex terrain such as mountain forests, the vital forest functions
are depending on such measures (Brang et al. 2006; Woltjer et al. 2008). Moreover, infrastructure
supports the mitigation of large scale disturbance impacts. This however leads to fragmentation of
ecosystems and has adverse effects to the biodiversity.
Reducing forest fragmentation by establishing connecting corridors between densely forested
regions contributes to increasing the natural adaptive capacity. Establishing a network of corridors
and stepping stones connecting protected areas has been suggested as an adaptive strategy to assist
species as they migrate in response to climate change (Halpin 1997; Harrington et al. 2001).
Corridors should be built to aid in the migration of species to other protected areas when an extreme
event has occurred (Bridgewater and Woodin 1990).
Forest management planning describes the processes of problem identification, development of
alternatives and selection of alternatives, embedded in an adaptive management cycle (cf. Rauscher
1999). One significant selection is the length of rotation, i.e. the period of years between when a
forest stand is established and when it receives its final harvest. A shortening of rotation length is an
adaptation option in regions with increasing forest growth, like in mountainous or boreal
environments. The reduced rotation length will also lower the risk of financial losses due to
calamities and counteract the reduced management flexibilities induced by excessive levels of
sanitation felling (e.g. Wermelinger 2004). However, structural changes of lower rotation lengths
need to be considered with regard to other forest services, like biodiversity via loss of large
diameter trees.
3. Landscape approach may be a solution
Landscape level approach would allow building a combination of highly adaptive stands with
simultaneous high level biodiversity and stands where adaptation measures do not support
biodiversity. This is however a complex task and gets even more complicated since also economic
and social standpoints have to be taken into account. The measure might be relevant from
ecological point of view, but not in economic or social point of view.
Since disturbance agents will gain more importance under the climate change, landscape level forest
planning, balancing stand level management goals and integrated forest protection measures, is of
increasing importance. A key approach in risk management is diversification of tree species
mixtures and management approaches between neighbouring forest stands or within a forestry
district to increase adaptive capacity (Lindner 2000; Bodin and Wiman 2007; Lindner 2007).
In developing alternative management strategies, forest planning aggregates stand scale
management options and aims for concerted application at the landscape level. Promotion of
diversity in landscape structure is seen as a strategy to promote resilience of forest ecosystems. At
larger geographical scales of management units and forest landscapes, various strategies can be
combined. For example, preferring natural regeneration in mixed forests with long rotation cycles is
incompatible with planting productive genotypes managed in short rotation cycles.
Identifying suitable landscape level management strategies can be facilitated with decision support
systems which include necessary simulation models. Integrated ecosystem models, for instance,
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.) 2010,
Instituto Politécnico de Bragança, Bragança, Portugal.