THE EFFECTS OF BIODIVERSITY CONCERNS ON ECONOMIC PROFITS OF TIMBER IN FOREST MANAGEMENT

The changing demands of today require a widened scope of forest management. Society is asking for sustainable forestry emphasizing biodiversity. Maintaining, improving and also integrating biodiversity into forest management plans have been a challenging task over the last decade. Biodiversity can be decomposed into measurable characteristics of individual stands by diversity indicators. Some examples of the indicators are; mean volume of deciduous trees, mean volume of deadwood and proportion of Old Growth Forests (OGF). OGF, play an especially important role in maintaining biodiversity having large living and dead trees. Also high variability of tree sizes is an important diversity feature. In forest ecosystems, there are tradeoffs between timber production and habitat for old growth dependent species. The purpose of this study is to estimate economic effects of ecological concerns on Net Present Values (NPV) of timber harvest in the Mustafa Kemal Paºa Planning Unit. To achieve this aim, distribution of age classes and the amount of the area of OGF are considered. A Linear Programming (LP) model was built maximizing the Net Present Value (NPV) of timber production and solved by a commercial LP solver. The model built for a 100 year planning horizon generating even age class distribution. Then, the amount of OGF was increased 5%, 10 % and 15 % respectively and the effects of these differences on NPV were analyzed. The results show that, if the forests are managed for maintaining biodiversity, the NPV of the profits of timber production is considerably reduced. In this way it would be possible to measure the opportunity cost of biodiversity in terms of financial returns