Keeping pace with forestry: Multi-scale conservation in a changing production forest matrix

Abstract

The multi-scale approach to conserving forest biodiversity has been used in Sweden since the 1980s, a period defined by increased reserve area and conservation actions within production forests. However, two thousand forest-associated species remain on Sweden's red-list, and Sweden's 2020 goals for sustainable forests are not being met. We argue that ongoing changes in the production forest matrix require more consideration, and that multi-scale conservation must be adapted to, and integrated with, production forest development. To make this case, we summarize trends in habitat provision by Sweden's protected and production forests, and the variety of ways silviculture can affect biodiversity. We discuss how different forestry trajectories affect the type and extent of conservation approaches needed to secure biodiversity, and suggest leverage points for aiding the adoption of diversified silviculture. Sweden's long-term experience with multi-scale conservation and intensive forestry provides insights for other countries trying to conserve species within production landscapes.

Keywords: Biodiversity conservation; Climate change mitigation; Even-aged forestry; Green-tree retention; Habitat loss; Protected areas.

Fig. 1

National trends in forest variables as collected by the Swedish National Forest Inventory (SEPA ; SFA ; SLU 2018). a Trees with diameter > 15 cm retained after final felling, as surveyed 5–7 years later. b Area covered by boreal forest over 80 years of age, and hemi-boreal and temperate forest over 60 years of age that have a basal area of at least 25% broadleaved trees. c Standing volume for select tree species and classes in millions of cubic metre on productive forest land. d Regeneration method and use of scarification as a percentage of logged area. e Standing volume per hectare at the age of final felling. f Percentage cover of ground layer vegetation, specifically cowberry Vaccinium vitis-idaea, bilberry Vaccinium myrtillus, all vascular plants and all bryophytes and lichens, on production forest land. Analyses exclude protected areas as of 2015 (b, e) or 2017 (c, f). The time period provided differs depending on data availability

Fig. 2

A conceptual framework illustrating the potential interdependence between protected forest areas and production forest intensity for forest habitat provision. We anchor the figure to estimates that 10–30% of productive forest lands requires protection to meet the species habitat requirements (Angelstam and Andersson 2001). The dashed line between ‘A’ and ‘B’ indicates the distance between a hypothetical current system state and meeting species’ threshold habitat requirements. The arrows indicate the two production forest trajectories considered (grey arrow = less intensive; black arrow = more intensive). Both arrows involve the same increase in protected forests (vertical distance on y-axis), but only the grey arrow meets species’ habitat requirements