Lubomír Šálek’s research while affiliated with Czech University of Life Sciences Prague and other places

The impact of climate change on forest ecosystems may manifest itself by a shift in forest vegetation zones in the landscape northward and into higher elevations. Studies of climate change-induced vegetation zone shifts in forest ecosystems have been relatively rare in the context of European temperate zone (apart from Alpine regions). The presented paper outlines the results of a biogeographic model of climatic conditions in forest vegetation zones applied in the Central European landscape. The objective of the study is a prediction of future silvicultural conditions for the Norway spruce ( Picea abies L. Karst.), which is one of the principal tree species within European forests. The model is based on a general environmental dependence of forest vegetation zones on the long-term effect of altitudinal and exposure climates defined by the mean and extreme air temperatures and the amount and distribution of atmospheric precipitation. The climatological data for the model were provided by a validated regional climate database for 2010 – 2090 according to the SRES A1B scenario, bound to specific geo-referenced points in the landscape. The geobiocoenological data in the model were provided by the Biogeography Register database which contains ecological data on the landscape bound to individual cadastres of the entire Czech Republic. The biogeographic model applies special programs (the FORTRAN programming language) in the environment of geographic information systems. The model outputs can be clearly graphically visualized as scenarios of predicted future climatic conditions of landscape vegetation zones. Modelling of the regional scenario of changes in the climatic conditions of forest vegetation zones reveals that in the prediction period of 2070 and beyond, good and very good climatic conditions for the cultivation of forests with dominant Norway spruce will be found only in some parts of its today’s native range in forest vegetation zones 5 – 8. Based on the results provided by the regional scenario, the authors of this paper recommend fundamental reassessment of the national strategy of sustainable forest management in the Czech Republic, stipulating that the current practice of spruce cultivation be reduced only to areas specifically defined by the biogeographic model. The paper shows that biogeographic models based on the concept of vegetation zoning can be applied not only in regional scenarios of climate change in the landscape but also as support tools for the creation of strategies of sustainable forest management.

The black walnut (Juglans nigra L.), an introduced species into the Czech Republic, is planted for its production of valuable timber. A systematic study of the black walnut growth rate at different localities and consequently the creation of standard volume tables under Central European conditions therefore appear to be of high relevance. The aim of our study was to reveal the black walnut growth pattern in its pure stands in two riparian forests along the Morava and Svratka River (Strážnice locality and Židlochovice locality, respectively). To describe and to compare relationships among diameter at breast height (dbh), tree height and age, we used a forest management plan and measured 573 and 670 trees in pure sample stands at Strážnice and Židlochovice, respectively. We found out that the measured mean DBH and mean height were consistently higher in Strážnice, however the relationships of DBH to height, age to DBH, and age to height showed the same pattern at both localities. The mean heights of trees were 16.3, 24.1, 28.7, 31.9, and 34.5 m in 20, 40, 60, 80, and 100 year age classes and were consistently taller in comparison with other, mainly European, regions. Therefore our results suggest the high potential of black walnut in timber production in riparian forests in the Czech Republic, mainly in the South Moravian region.

The wedge prism, which is generally used for the measurement of basal area in diameter at breast height, is also a tool for the measurement of distance as well as for the measurement of diameters at a certain height of the stem, in the upper stem. Measurements using the wedge prism are based on the same principle as measurements using Bitterlich mirror relascope. This method is appropriate for non-destructive determination of stem volume. Moreover, the wedge prism can be used for the sorting of logs in standing trees when the small end of expectant assortment has to be known. As the wedge prism is a common tool for foresters, its usage seems to be larger than only the measurement of basal area.

In conservation biology, there is a general consensus that protected areas (PAs) are one of the most effective tools for biodiversity protection. Worldwide, the area of PAs is continually increasing. But is the effectiveness of biodiversity protection improving with it? Since many PAs only exist as “paper parks” (i.e. they exist on maps and in legislation but offer little actual protection), the answer is uncertain. Moreover, it has long been known that, not only an increase in the extent of PAs, but also the efficiency of their management is fundamentally important for effective nature conservation. Therefore, there is a wide-ranging discussion about the actual effectiveness of PAs and factors that influence it. In the course of the EU pre-accession phase, a comprehensive field mapping of natural habitats took place in the Czech Republic in years 2001−2004. The mapping results were used to designate Special Areas of Conservation (SACs) as part of the Natura 2000 network. In this study, the aim was to evaluate the effectiveness of this newly created system of SACs for protection of biodiversity represented by the mapped natural habitats. The NCEI index (Nature Conservation Effectiveness Index) was applied, calculated as the total area of a particular habitat type in all SACs in the Czech Republic divided by the total area of that same natural habitat in the entire Czech Republic. Habitat protection in the Czech Republic is focused primarily on the smallest types of rare habitats, many of which are classified as critically endangered. The Czech national system of SACs provides protection to a total of 4,491.68 km2 of natural habitats. Based on these results, it can be concluded that the overall effectiveness of the SAC system in the Czech Republic, which is specifically aimed at protecting natural habitats, is low (NCEI = 0.36). Nevertheless, the critically endangered habitats receive maximum protection (NCEI = 1).

Black walnut (Juglans nigra L.) is an introduced north-American species with highly valuated timber. In the Czech Republic, it occupies cca 1,000 ha only, particularly in the flood-plain area of south Moravia. Comparing to native tree species, black walnut shows high volume and value production. On the contrary, it is exposed to pressure from the part of environmentalist organizations, due to growth at the valuable sites. Aim of the presented study is the summarization of available data from abroad as well as from the Czech Republic, to gather information concerning the production potential and environmental effects of this species in Czech conditions. The study summarizes literature sources concerning volume and volume production as well as the available data on environmental effects, especially effects of black walnut on the plant communities in the forest ecosystems. Results document the excellent production potential of this species in proper conditions and conditions for minimizing risks for the forest environment. More attention should be paid to this species in the Czech conditions, its position in the Czech forestry should increase in restricted controlled extent.

The regional effects of climate change on forest ecosystems in the temperate climate zone of Europe can be modelled as shifts of forest vegetation zones in the landscape, northward and to higher elevations. This study applies a biogeographical model of climate conditions in the forest vegetation zones of the Central European landscape, in order to predict the impact of future climate change on the most widespread tree species in European deciduous forests—the European beech (Fagus sylvatica L.). The biogeographical model is supported by a suite of software applications in the GIS environment. The model outputs are defined as a set of conditions - climate scenario A1B by the Special Report on Emission Scenarios (SRES) for a forecast period, for a specified geographical area and with ecological conditions appropriate for the European beech, which provide regional scenarios for predicted future climatic conditions in the context of the European beech’s environmental requirements. These predicted changes can be graphically visualized. The results of the model scenarios for regional climate change show that in the Czech Republic from 2070 onwards, optimal growing conditions for the European beech will only exist in some parts of those areas where it currently occurs naturally. Based on these results, it is highly recommended that the national strategy for sustainable forest management in the Czech Republic be partly re-evaluated. Thus, the presented biogeographical model of climate conditions in forest vegetation zones can be applied, not only to generate regional scenarios of climate change in the landscape, but also as a support tool for the development of a sustainable forest management strategy.

This study examined the influence of tree species and structural diversity on the production of high-quality logs. The data were from the regional forest inventory of the University Forest Enterprise, Czech Republic, performed from 2009 to 2011 on 1188 sample plots. For every sample plot, we quantified 38 diversity indicators. The plots were divided into four age groups (young, middle-aged, old and uneven-aged stands). The anticipated proportion of high-quality logs was determined using local assortment tables. For each age group, the impact of species and structural diversity indicators on the volumetric proportion of high-quality logs was assessed using backwards multiple regression. The relationship between diversity measures and log quality changed with stand age. In old stands, horizontal structure had a more profound effect on the proportion of high-quality logs. In young stands, species diversity and vertical structure were more influential. In middle-aged stands, the impact of stand diversity on log quality was most complex. In uneven-aged stands, vertical structure was the diversity component most affecting the proportion of high-quality logs. Overall, the proportion of best quality logs increased with the increasing stand diversity in all age classes, suggesting that timber production and stand diversity are not contradictory management goals. EDITED BY Sheila Ward

The present study examines the relationship between the quality of timber production and the species and structural diversity of forest stands. The data used came from a regional forest inventory of the University Forest Enterprise "Kostelec nad Černými lesy", Czech Republic. The inventory was performed from 2009 to 2011 on 1,188 sample plots that represented 86 strata defined by the combination of three variables: site (5 categories), age (12 categories) and canopy cover (5 categories). On each sample plot, we quantified 171 partial biodiversity indicators that represented species or structural diversity. The quality of timber production was specified by four indicators quantified using local assortment tables. In total, we analysed 58,824 univariate linear regressions describing the relationships between diversity indicators and timber quality in individual strata. The results revealed that their relationship changes with stand age. The proportion of the best-quality assortments increases with the increasing species richness in all age categories.