The practice of salvage logging dead and damaged timber following large high severity disturbances has raised much controversy, partly because of the negative ecological effects that such practices have on forest ecosystems. Many of the studies on salvage logging effects, however, have been done on sites damaged by large, severe disturbances. Less is known about the ecological consequences of salvage logging following intermediate severity disturbances that cause partial canopy damage at smaller scales. We examined the response of the herbaceous layer and tree regeneration to salvaged and non-salvaged treatments following small-scale intermediate severity disturbances in eight mixed beech (Fagus sylvatica L.) dominated forest stands in Slovenia. The cover and diversity of herbaceous vegetation, as well as the density and diversity of tree regeneration were similar between treatments across the study sites. The only notable differences between the treatments were that salvaged sites had a larger proportion of shade intolerant tree species in the regeneration layer, while non-salvaged sites tended to have a more well-developed regeneration layer in taller height classes. The results suggest that salvage logging following small-scale intermediate severity disturbances may not hinder forest recovery in mixed beech dominated forests.
The research deals with the effects of forest tending on stand structure and composition on abandoned agricultural lands and possibilities of directing succession development of these stands. This attempt to evaluate the tending ran five vegetation seasons and was divided into three parts. In the first part we checked the initial condition and performed the tending. Setting the goals which are formed according to the development phase and consequent expediently performed silvicultural tending actions, on the abandoned agricultural lands in the thicket phase it is necessary to give priority primarily to the pioneer species due to their protective role, while in the pole stand phase the stress should be laid to the species, interesting from the silvicultural viewpoint, e.g. noble broadleaved trees, minority tree species and climax species. In the second (after three vegetation seasons) and third (after five vegetation seasons) part we again checked the condition and thereby the effects of tending. We applied statistical methods for studying the effects of tending. With the tending we stimulated shifting of the tree species, which are important stand builders in the preliminary phases of succession (above all sycamore maple), and increased diameter increment of the crop trees. Through timely tending actions it is possible to stimulate natural succession on the abandoned agricultural lands and direct it toward economically interesting and ecologically stable forest, whereby it is necessary to stress that low intensity actions are needed for a stable stand, otherwise stand stability is endangered. On the lands, where other roles are in the foreground, stand quality is of secondary importance. The costs of thicket tending on abandoned agricultural lands are lower than the costs of pole stand tending.
Real-time synthesis of realistic tree models is a desirable functionality for computer games, simulators, and landscape design software. Self-organizing tree models that adapt to the environment are a welcome addition and central to various 3D design tools but present a challenging task for interactive use even on modern commodity hardware. The paper describes the implementation of a complete selforganizing tree synthesis method running on a contemporary graphics processing unit using OpenCL. We demonstrate that generation and display of tree-populated scenes with shadows at interactive rates can be achieved by utilizing the massively parallel GPU architecture to accelerate the computationally intensive steps of the method. A comparison with the performance of single-threaded and CPU-based OpenCL implementation of the same method is reported.