Diversity-oriented silviculture in the Boreal Zone of Europe

摘要

This article presents the concepts and models of diversity-orientated silviculture in the Boreal Zone of Europe based on the literature, Finnish national forest inventories and field experimental data. The basic idea of following the natural processes of forest ecosystems in silvicultural practices has existed since the last century, but appropriate comparative materials for modelling have been only scantily available previously. The stand structure classification used in this study is based on therange and shape of stem distribution, and uses national forest inventory and field experimental data from Finland. The 2 main groups used are even-sized and uneven-sized. A subclass of the latter, regularly all-sized, with dbh (diameter at breast height) distribution resembling a reversed-J, forms the primary basis for treatment models. This kind of structure, following the development and dynamics of natural mixed stands, fulfils the requirements for biodiversity according to international resolutions. Single tree selection and group selection are primarily the main treatments and seed tree and shelterwood fellings are secondary treatments used in this diversity-orientated silviculture. In addition, regimes aiming to diversify even-sized stands in different developmental stages are discussed.