Epsilon Archive for Student Projects

Abstract

Sweden’s historical and current forestry regime has created structurally simplified
forest stands with little resemblance of boreal old-growth forests, leading to a
decline in many forest dwelling species. Retention forestry was introduced to
counteract the negative development by retaining biologically important forest
elements. Retention patches are intact forest areas left to represent conditions in the
pre-harvest stand for harbouring of threatened species and structurally enriching
managed forests. However, many biodiversity preservation goals connected to
forests remain unfulfilled, which indicate a need for evaluation of what is retained
during harvest and possible influences on why. I used the Swedish Forest Agency
method for inventorying woodland key habitats to evaluate differences in substrate
supply, conservational quality and physical prerequisites in retention patches
compared to structurally similar reference forest stands located in spruce�dominated boreal forests in Hälsingland, Sweden. My results showed how retention
patches scored lower in the natural value assessment, contained less deciduous live
conservation trees and less coarse deadwood. In general, substrate amounts are
either lower or indifferent in retention patches compared to in reference forests,
indicating that retention patches are not structural hotspots. If retention patches do
not hold equal conservation values as the pre-harvest stand, the forest landscape
would continuously be impoverished, and the threatened species disfavoured. The
structure of retention patches, underlying causes of retention decisions, and
following implications for biodiversity need further studying to ensure that areas
with the highest conservational importance are preserved.