Open access publications in the SLU publication database

Abstract

The new Swedish Forestry Act states that the forests should be sustainably managed in
a profitable way and, at the same time, the current levels of biodiversity should be
maintained. This and the pressure from consumers for forest products to be produced
in a way that protects biodiversity have changed forestry towards a more nature
oriented management. An estimation of the effects of this nature conservation on
timber yields and potential cut must be included in forest scenario modelling to assess
the long term impacts.
An important component of preserving biodiversity in forests in this nature oriented
management is to adjust management measures in edge zones adjacent to mires,
riparian zones, non-productive hills, etc. Examples of management measures in edge
zones are no cutting, modified thinning, single tree selection or leaving behind large
trees. These spatial considerations can now be dealt with in long-term forecasts using
HUGIN, a system based on sample plot data from the Swedish National Forest
Inventory (NFI). This is because of the improved description of the context of the NFI
sample plots in the landscape. Furthermore, geographical positions are determined
using the Global Positioning System (GPS), which facilitates the combination of NFI
data with other data sources.
A schedule of how to select sample plots located in forest habitats that are valuable for
biodiversity is shown.
Analyses of the new NFI data show that approximately 11 % of the productive forest
land is located within 25 meters of mires and non-productive hills and 3 % is located
in riparian zones. Forest scenario modelling using the HUGIN system will now be able
to estimate the reductions in the long-term potential cut due to nature conservation in
edge zones.