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An additional and underutilized resource that accumulates annually is post-consumer wood. The annual potential volume of this resource of wood raw material in Ukraine is about 2.0 million tons. This important source of wood raw materials, due to the lack of a regulatory framework, scientific and technical foundations for use, classification, technological developments and practical recommendations, has not yet received proper use at woodworking enterprises in Ukraine. We have made the first attempts to study the physical and mechanical properties of the post-consumer wood and suggest ways to use it. Among a variety of indicators of the mechanical and physical characteristics of used wood specimens from roof structures, we have identified the most important ones that are important for the use of such wood in the manufacture of panel structural materials, in particular in the production of blockboards. It is substantiated that the identification of the main indicators of post-consumer wood (PCW), and their comparison with the same indicators of primary wood (PW), in particular, the main softwood species, is an urgent scientific problem, since provisioning the regulatory database will ensure the manufacture of high-quality wood products with maximum consideration of the mechanical and physical characteristics of this potential reserve of raw materials, which is advisable to use in woodworking technologies for the production of structural materials and components of furniture products. Physico-mechanical parameters of PW and PCW of pine, spruce, fir and larch were identified and it was found that with time of operation under different conditions they change, mainly towards decreasing their values: density – by 1.54-4.67%; impact hardness – by 1.37-4.11%; static hardness – by 0.72-7.11%; cross-breaking strength – by 5.94-8.33%, shearing strength – by 3.08-7.23%; compressive strength along the fibers – by 1.72-8.89%. The main causes of age-related changes in the properties of PCW are due to the following factors: biological – partial internal rot, weathering, insect damage; mechanical – scratches, shearing, small holes from fasteners and other defects from use; operational – the influence of dynamic and power loads, surface finishes and other factors on structural elements of wood products. Possessing the obtained indicators and knowing the change in the physical and mechanical properties of PCW with age, we can recommend this additional wood material for the manufacture of structural materials: with mechanical damage visible on the surface and color changes – for the manufacture of blockboards; with high-quality surfaces - for the manufacture of furniture panels The results of studying the indicators of the physical and mechanical properties of PCW of the main softwood species made it possible to understand the nature of the change in these indicators in comparison with PW, to elaborate practical recommendations for efficient material processing, and to fill the regulatory database.

For forest sustainability and vulnerability assessment, the landscape scale is considered to be more and more relevant as the stand level approaches its known limitations. This review, which describes the main forest landscape simulation tools used in the 20 European case studies of the European project "Future-oriented integrated management of European forest landscapes" (INTEGRAL), gives an update on existing decision support tools to run landscape simulation from Mediterranean to boreal ecosystems. The main growth models and software available in Europe are described, and the strengths and weaknesses of different approaches are discussed. Trades-offs between input efforts and output are illustrated. Recommendations for the selection of a forest landscape simulator are given. The paper concludes by describing the need to have tools that are able to cope with climate change and the need to build more robust indicators for assessment of forest landscape sustainability and vulnerability. [ABSTRACT FROM AUTHOR]

Background The quantitative impact of forest management on forests’ wood resource was evaluated for Picea and Fagus mixed forests. The effects on the productivity of tendering operations, thinnings and rotation length have seldom been directly quantified on landscape scale. Methods Two sites of similar fertility but subject to contrasted forest management were studied with detailed inventories: one in Germany, the other in Romania, and compared with the respective national forest inventories. In Romania, regulations impose very long rotations, low thinnings and a period of no-cut before harvest. In contrast, tending and thinnings are frequent and intense in Germany. Harvests start much earlier and must avoid clear cutting but maintain a permanent forest cover with natural regeneration. While Germany has an average annual wood increment representative for Central Europe, Romania represents the average for Eastern Europe. Results The lack of tending and thinning in the Romanian site resulted in twice as many trees per hectare as in the German site for the same age. The productivity in Romanian production forests was 20 % lower than in Germany despite a similar fertility. The results were supported by the data from the national forest inventory of each country, which confirmed that the same differential exists at country scale. Furthermore, provided the difference in rotation length, two crops are harvested in Germany when only one is harvested in Romania. The losses of production due to a lower level of management in Romania where estimated to reach 12.8 million m3.y-1 in regular mountain production forests, and to 15 million m3.y-1 if managed protection forest is included. Conclusions The productivity of Picea and Fagus mountain forests in Romania is severely depressed by the lack of tending and thinning, by overly long rotations and the existence of a 25-years no-cut period prior to harvest. The average standing volume in Germany was 50 % lower than in Romania, but the higher harvesting rate resulted in more than doubling wood production. Considering the mitigation effects of climate change by forests, it emerges that the increase in standing volume of forests in Romania is smaller than the additional harvest in Germany which serves fossil fuel substitution.

Background: The quantitative impact of forest management on forests' wood resource was evaluated for Picea and Fagus mixed forests. The effects on the productivity of tendering operations, thinnings and rotation length have seldom been directly quantified on landscape scale. Methods: Two sites of similar fertility but subject to contrasted forest management were studied with detailed inventories: one in Germany, the other in Romania, and compared with the respective national forest inventories. In Romania, regulations impose very long rotations, low thinnings and a period of no-cut before harvest. In contrast, tending and thinnings are frequent and intense in Germany. Harvests start much earlier and must avoid clear cutting but maintain a permanent forest cover with natural regeneration. While Germany has an average annual wood increment representative for Central Europe, Romania represents the average for Eastern Europe. Results: The lack of tending and thinning in the Romanian site resulted in twice as many trees per hectare as in the German site for the same age. The productivity in Romanian production forests was 20 % lower than in Germany despite a similar fertility. The results were supported by the data from the national forest inventory of each country, which confirmed that the same differential exists at country scale. Furthermore, provided the difference in rotation length, two crops are harvested in Germany when only one is harvested in Romania. The losses of production due to a lower level of management in Romania where estimated to reach 12.8 million m.y in regular mountain production forests, and to 15 million m.y if managed protection forest is included. Conclusions: The productivity of Picea and Fagus mountain forests in Romania is severely depressed by the lack of tending and thinning, by overly long rotations and the existence of a 25-years no-cut period prior to harvest. The average standing volume in Germany was 50 % lower than in Romania, but the higher harvesting rate resulted in more than doubling wood production. Considering the mitigation effects of climate change by forests, it emerges that the increase in standing volume of forests in Romania is smaller than the additional harvest in Germany which serves fossil fuel substitution. [ABSTRACT FROM AUTHOR]