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Due to traditional forest management, the primary goal of which is the production of raw wood material, commercial forest stands are characterized by low biodiversity. At the same time, commercial forests make up the majority of forests in the Central European region, which means a significant impact on the biodiversity of the entire large region. Saproxylic species of organisms are a frequently used criterion of biodiversity in forests. Based upon the analysis of 155 scientific works, this paper defines the fundamental attributes of the active management supporting biodiversity as well as the preservation of the production function. Using these attributes, a model management proposal was created for three tree species, which takes into account the results of research carried out in the territory of the University Forest Enterprise of the Czech University of Life Sciences Prague, since 2019. The optimum constant volume of deadwood in commercial stands was set at 40–60 m3/ha, 20% of which should be standing deadwood. The time framework is scheduled for an average rotation period of the model tree species, while the location of deadwood and frequency of enrichment must comply with the rate of decomposition, the requirement for the bulkiest dimensions of deadwood possible, and the planned time of tending and regeneration operations in accordance with the models used in the Czech Republic. The goal of active management is to maintain the continuity of suitable habitats for sensitive and endangered species. The estimates of the value of retained wood for decomposition can be as high as 45–70 EUR/ha/year for spruce and beech, and about 30 EUR /ha/year for oak.

The article addresses the issues of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) production in the Czech Republic (CR). Our analysis shows that the tree species can occupy 149,616–163,713 ha in the CR (with respect to ecological limits set by the Czech legislation). The potential economic effect expressed by the gross yield of forest production might be higher by 27–30 million EUR·yr^–1.  The results of the analysis support the forest owners’ interest to extend Douglas-fir production in the CR, similarly like it has been extended systematically in all European countries where natural conditions allow.  

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Climate change is increasingly affecting forest ecosystems. Modifying the species composition towards species mixtures with a higher potential to mitigate the negative effect of climate change is one of the basic silvicultural measures. Potential economic and production impacts of these actions need to be assessed. This study therefore aims to evaluate the economic and production effect of species composition change as a result of the adaptation of forest ecosystems to climate change. The differences between the value production of Norway spruce (Picea abies /L./Karst.), Douglas fir (Pseudotsuga menziessi/MIRBEL/FRANCO) and European beech (Fagus sylvatica L.) on fresh soils (represented mainly by mesotrophic cambisols), and soils affected by ground water (mainly pseudogley forms of cambisols and pseudogleys) were evaluated. The study was conducted on the area of the forest enterprise of the Czech University of Life Sciences (UFE) situated in the Central Bohemia region. For a model comparison of height and volume growth of Douglas fir and Norway spruce in this area, all stands (pure and mixed) with both species represented were analysed using the data from the current forest management plan and Korf’s growth function. The course of current and mean height increments over time is very similar, yet with constantly higher annual increments for Douglas fir. In 100 years, the mean stand height of Douglas fir is 6 m larger than that of Norway spruce. Production and economic potential were also evaluated. At the rotation age, the volume and value production of Douglas fir was 30% to 50% higher than that of Norway spruce. A higher share of Douglas fir in the total forest area would lead to an important value increment of the forests in the study area. Different results were achieved by comparing the yield potential of Norway spruce with European beech, which most often substitutes spruce at middle altitudes. Beech potential yield is only 40–55% of the spruce yield level.

This article discusses the production potential (and limits) of the forests in the Czech Republic (CR). The calculation respects ecological limits set by typological system and the Czech forestry legislation. The key criterion of the production evaluation is the total mean increment. Usually, a forest owner can choose amongst several variants of management. The analysis in this work examines the two limit variants -the minimum and maximum production potential. The results show that, e.g., the Norway spruce share might be 19 to 48% of the total area of Czech forests (51.4% at present). The target management the owners opt for (Norway spruce, pine, oak, and beech) can, in the future, influence the timber processing industry, the main purchaser of timber raw material from Czech forests. The maximum variant shows 9,134 thousand m 3 of available coniferous round timber, while the minimum one only 3,802 thousand m 3 per year. Therefore, the timber processing industry should keep a close watch on the situation and either try to persuade forest owners to choose the alternative of the target management that would provide sufficient assortment for timber processing, or adjust the manufacture to the possible changes in the species composition of the forests.

aBstraCt:The article deals with economic aspects of sustainable forest management. The analysis stems from Plíva's typological system. Several hundreds of variants were calculated for forest silviculture profitability classified according to management intensity, target management system, proportion of ameliorating and improving species, proportion of natural regeneration, and set of forest types. The results show a possibility of labour saving and also marked differentiation of the effect of wood production function depending on natural and production conditions and management intensity.Keywords: economic effectiveness; sustainable forestry management; management intensity; forestry production gross profit; evaluation 429A cardinal background material for project elaboration was the work of Plíva (1998) The goal of Plíva's work was to draw up a guideline for the application of FTG in differentiated forest management based on a sustainable management concept as well as its effectiveness.The author links up to his own works for broadly envisaged management complexes and he modifies the respective data to the new concept, he determines them for selected FTG, and amends them with new information for multi-purpose use. FTGs are combined according to the intensity and purpose of management.Based on the comparison of potential production of target composition (PP) with a degree of the system's environmental functions significance (EP) five degrees of management intensity (IM) are created with several types of target management defined by nature characteristics and major target species. Both these broadly envisaged units provide comprehensive orientation in basic principles, however they do not substitute FTG neither management set of stands.As the author states, the work deals with an assessment of real possibilities of sustainable forest management implementation with respect to the current forest conditions and also the valid legal regulations. The author claims that contrary to the frequently presented and fairly simplified idea of generous transformation of present mostly monocultural types into mixed and optimally structured stands this work transforms the conditions into more real ideas and more achievable targets.In this work management intensity forms a basic framework for grouping FTG according to intensity.Active impacts of a stand upon the environment are expressed by its environmental functions, i.e. positive influences of the forest upon its environment. Their synergetic action within an FTG constitutes then the ecological potential (EP) similarly like the production function (value of production) determines the production potential (PP) of the FTG.The ecological and production potentials affect the management intensity as quantitative indicators. As the two potentials act in relation to management intensity in reverse directions (with an increasing 13.8-11.4 BE 9.9-9.6 BE 9.9-9.6 BE 9.9-9.6 BE 9.9-9.6 BE 9.9-9.6 BE ecological function the management intensity drops down to the level of protection for...

The article presents selected results of the project of the Czech National Agency for Agricultural Research, "Differentiation of intensities and management practices in relation to forest biodiversity and economic sustainability of forestry" executed at the Department of Forest Economy and Forestry Management, Faculty of Forestry and Wood Sciences, Czech University of Agriculture in Prague. The results included the quantification of forest rotation periods derived from total mean increment, total mean value increment, and annual gross profit of forest production. Significant differences between the rotation period currently recommended and the rotation period relevant to economic optimum (maximum) were observed. The better the forest site (site quality class), the bigger is the difference. Keywords: felling maturity; rotation age; rotation period; maturity of non-market forest functions; economic maturity Abstrakt Příspěvek uvádí vybrané výsledky projektu NAZV "Diferenciace intenzit a postupů hospodaření ve vztahu k zajištění biodiverzity lesa a ekonomické životaschopnosti lesního hospodářství", který je řešen na katedře ekonomiky a řízení lesního hospodářství Fakulty lesnické a dřevařské České zemědělské univerzity v Praze. Byla provedena kvantifikace doby obmýtní, stanovená na základě celkového průměrného přírůstu, celkového průměrného přírůstu hodnotového a na základě čistého důchodu lesní výroby (hrubého zisku lesy výroby). Byla zjištěna značná diference mezi dobou obmýtní, v současnosti doporučovanou a dobou obmýtní, odpovídající ekonomickému optimu (maximu). Tato diference se zvyšuje od méně kvalitních směrem ke kvalitnějším stanovištím (bonitním stupňům). Klíčová slova: mýtní zralost; mýtní věk; doba obmýtní; mimoprodukční zralost; ekonomická zralost 1. Úvod Mýtní zralostMýtní zralost se definuje jako stav porostů, optimální pro těžební zásah. Vztahuje se buď na jednotlivé porosty, kde se vyjadřuje mýtním věkem, nebo na hospodářské soubory, kde se vyjadřuje dobou obmýtní. Pro lesní hospodářství to jsou velmi závažná hospodářsko-úpravnická kritéria, základ pro časovou a těžební úpravu lesa, které rozhodujícím způsobem ovlivňují výšku mýtní těžby.Odborná literatura definuje tyto druhy doby obmýtní (Halaj 1990): Kvantitativní zralost (nejvyšší objemové produkce)Kvantitativní mýtní zralost je stav, ve kterém porosty dosahují maximální průměrné roční objemové produkce. To odpovídá věku kulminace průměrného přírůstku celkové produkce. Současně v tomto věku nastává rovnost přírůstu CPP (celkový průměrný přírůst) a CBP (celkový běžný pří-růst).Tato zralost představuje spodní hranici mýtní zralosti dřevin. Při nižším mýtním věku by se nevyužívaly potenciální produkční možnosti lesa, vznikaly by tedy přírůstové ztráty. Výhodou kvantitativní zralosti (v porovnání s jinými druhy zralosti, např. hodnotovou, ekonomickou) je to, že je charakterizovaná jenom zákonitostmi růstového procesu -kulminací objemového CPP. Závisí na dřevině, bonitě a zakmenění. Nepodléhá tedy cenovým, nákladovým a jiným změnám. Určuje se...