Effects of forest management on forest biodiversity

Forests host approximately 80 % of species of all terrestrial organisms. Human pressure on forest ecosystems drastically increased during 20th century and poses a constant threat to global biodiversity. The aim of this thesis is to summarize current knowledge of the effects of forest management on organisms and to identify underlying mechanisms. The oldest forms of forest management techniques were coppicing and coppicing with standards which enable relatively high biodiversity of species of early successional stages. Transition to classical intensive forestry caused shielding vegetation from the sun and decrease of heterogeneity. In recent decades some further intensification of management is practiced by using fast growing trees, but awareness of the need to establish sustainable forestry conditions strenghtens. Managed forest contrary to natural one has substantially lower average age of trees, it shows spatial homogeneity and old and dead trees, elements that are tied to high diversity of organisms, do not occur. Species composition of woods changes often. Anthropogenic management also disrupts and weakens the natural disturbation regimes. In many economically developed countries forests have been fragmented for a long time and in vastly forested areas that have persisted to the 20th century massive..