Abstract

Five management regimes were theoretically applied and evaluated in a 10 000 ha boreal forest landscape. Four regimes were designed to enhance conditions for biodiversity conservation, by establishing reserves and by modifying stand management. One regime was purely for timber production. Effects on biodiversity were assessed in terms of changes in population sizes within species or as number of species within ecological groups of the Red-listed species in the landscape. Assessments were based on the effects of management regimes on natural features of significance to animal and plant diversity. Effects on growing stock, harvest level, and economic return were assessed by means of the Forest Management Planning Package. Results indicate that biodiversity can be preserved only if the landscape is managed to satisfy the demands of species that require continuity in habitat conditions, and if management recognises fire-generated successions in boreal forest. Such management encompasses a system of patches managed so that important successional stages are always present in the landscape. The regime based on traditional silviculture did not encompass such features and, consequently, did not maintain biodiversity in the landscape. In the traditional silviculture regime, the future amount of deciduous trees was constant while the amount of old forest strongly decreased. As expected, this regime also generated the highest economic output. The decrease in harvested volumes and net incomes in the other regimes was approximately proportional to the reduction in non-protected, productive forest land.