Search Results (12)

Norway Spruce (Picea abies (L.) H. Karst.), a timber species of significant economic and ecological importance in the Northern Hemisphere, faces increasing threats imposed by drought and bark beetle infestation intensified by ongoing climate change. Despite the extensive mortality within stands, a small proportion of mature trees remarkably survive during severe bark beetle outbreaks. Hypothesizing that bark beetle resilience is genetically determined and thus is under natural selection, we anticipated that there is a genetic variation in genome regions linked to the respective resistance in surviving trees. In the Bohemian Forest, restricted to the area of the Czech–Austrian–German border, we identified those resistant individuals, referred to as the “Last Trees Standing” (LTS). Concurrently, we collected reference samples from randomly selected individuals from natural regeneration within concerned sites (seedlings, young trees) and in adjacent unaffected stands (mature trees). Genomic data were generated on a 50K SNPs genotyping array. We conducted a population genetic study based on the Discriminant Analysis of Principal Components (DAPC) method as well as the Genome-Wide Association Study (GWAS). We identified 12 markers (SNPs) significantly associated with tree survival using this approach. Three of those SNPs are located within the genes with the known function in Arabidopsis thaliana orthologs. After further confirmation, we argue that the identified SNPs can be instrumental in identifying trees of higher resistance to bark beetle infestation. Full article

The climatic changes that took place in Europe during the Quaternary period influenced plant habitats as well as their species and vegetation composition. In this article, biogeographical studies on Hercynian mountain plants that include data for the Alps, Carpathians, and European lowlands are reviewed in order to discuss the phylogeographical structure and divergence of the Hercynian populations from those in other European mountain ranges, Scandinavia, and lowlands. The analyzed studies show specific phylogeographical relations between the Hercynian mountains, Alps, Scandinavia, Carpathians, and European lowlands. The results also indicate that the genetic patterns of plant populations in the Hercynian Mountains may differ significantly in terms of origin. The main migration routes of species to the Hercynian ranges began in the Alps or Carpathians. Some species, such as Rubus chamaemorus L., Salix lapponum L., and Salix herbacea L., are glacial relics that may have arrived and settled in the Hercynian Mountains during the Ice Age and that survived in isolated habitats. The Hercynian Mountains are composed of various smaller mountain ranges and are a crossroads of migration routes from different parts of Europe; thus, intensive hybridization has occurred between the plant populations therein, which is indicated by the presence of several divergent genetic lines. Full article

Forest fires are becoming a more significant problem in Central Europe, but their danger is not as high as that in Southern Europe. The exception, however, is forest fires occurring in disturbed areas (windthrow and bark beetle outbreak areas), which are comparable in severity and danger to the most serious forest fires. In this study, we describe the current situation in Central European countries in terms of fire protection for disturbed areas in managed forests and forest stands left to spontaneously develop (secondary succession). If a country has regulations and strategies in this area, they are often only published in the local language. In this review, we combine information from all Central European countries and summarize it in a unified international language, provide an opportunity for local authorities to express their own experiences, and integrate data from worldwide scientific research. Thus, this paper may be considered a universal guide for managing fire protection and preparedness in disturbed areas and can serve as a reference for the establishment of strict legislative rules at the state level. These laws must be obligatory for all stakeholders in individual countries. The motivation for this study was two large forest fires in an area left to spontaneously develop in the Bohemian Switzerland National Park in the Czech Republic and Harz Mountains in Germany in the summer of 2022. These incidents revealed that fire prevention legislation was inadequate or nonexistent in these areas. The strategy of the European Union is to increase the size of protected areas and spontaneous development areas. Therefore, we consider it necessary to provide governments with relevant information on this topic to create conditions for better management of these destructive events. Full article

The accurate estimation of bark thickness is important for foresters for several reasons. It is crucial for timber volume estimation and can help improve the quality of forestry records, and bark has a growing commercial importance as a high-value bioresource. The problem is that models such as the Czech Cubic Tables (CCT) polynomial model are frequently unique. Furthermore, the official method requires rounding down the midspan over-bark diameter (DOB) to the nearest centimetre to estimate the double bark thickness (DBT) and merchantable timber volume. Therefore, we verified the significance of the effects of rounding down the midspan DOB on DBT using a dataset of 438 recently harvested Norway spruce (Picea abies L. Karst.) logs from the Central Bohemian region. The correlation analysis showed that for measured data without rounding down the diameters, the variability of the DBT was able to explain only 8% of the DOB variability. As for the rounded-down data, the coefficient of determination was slightly higher, reaching 9%. The paired-samples T-tests showed a significant difference between the DBT as calculated directly from measured data and that from the rounded-down over-bark diameters (p < 0.05). The polynomial and linear models underestimated the DBT (2.24 and 1.75 mm on average, respectively) on measured data. In contrast, for data from the rounded-down DOB, the models overestimated the DBT (2.70 or 3.18 mm on average, respectively). Full article

This study examines the soil environment of eight charcoal kiln platforms and the neighboring soil in Czech and Bohemian low-altitude forest stands. Both mixed and undisturbed soil samples were used to assess the hydrophysical soil properties, nutrient content, cation exchange capacity, enzyme activity, and soil active carbon content, while soil color, stoniness, root density, and horizon thickness were estimated in the field. Charcoal-rich horizons had high total organic carbon concentrations and total nitrogen content (about 150% and 40% higher than in the organomineral horizons of the control plot, respectively), with total carbon stocks being higher than those in neighboring forest soils. Fine root density was highest in the charcoal-rich horizons, encouraged by high soil porosity, aeration, and favorable chemical properties. Enzyme group activity differed between individual soil horizons and kiln and control plots, with depolymerization enzyme activity highest in charcoal-rich horizons and humification enzyme activity highest in mineral horizons. Phosphatase, chitinase, and phenoloxidase activity were highest in charcoal-rich horizons, while β-glucosidase activity remained similar across horizons. After long-term abandonment, kiln sites shift from inhospitable sites to localized hotspots for plant and microbial growth, having more favorable physical, enzymatic, and chemical soil properties than the surrounding areas. This study confirmed that kiln production platforms act as microhabitat hotspots, also providing information on a wide spectrum of soil properties linked with soil microorganisms and root growth. Full article

Improving ecological connectivity (EC) within landscapes by establishing corridors and ecological networks has been proposed to counteract the negative effects of habitat fragmentation and climate change on biodiversity. To be functional, ecological networks should be kept free of opportunistic invasive species that can disrupt EC between protected areas and cause biodiversity loss. The present study focused on perennial herbaceous species whose occurrence in the Adriatic-Ionian region has increased in the last two decades, namely common milkweed (Asclepias syriaca), Jerusalem artichoke (Helianthus tuberosus), Japanese knotweed (Reynoutria japonica), Bohemian knotweed (Reynoutria × bohemica), giant hogweed (Heracleum mantegazzianum), giant goldenrod (Solidago gigantea), Canadian goldenrod (Solidago canadensis), and Bermuda buttercup (Oxalis pes-caprae). All species have a high potential to spread in grasslands, abandoned agricultural fields, forest edges, and riparian areas and pose a significant threat to native plant communities and biodiversity. Restoring heavily infested sites is a major challenge because these perennial invaders are very persistent and tend to alter the soil environment in invaded habitats and prevent the recolonization of native plant communities. Therefore, early action should be taken to prevent the spread of these environmental weeds in ecological networks and protected areas with high conservation value. Full article

Land cover evolution is an environmental factor that can be used to characterize forest ecosystem services (FES). This study aims to analyze the change in forest cover and water bodies between 1990 and 2018 in the whole Czech Republic, and in the Central Bohemian and South Moravian regions, and its effects on freshwater provision. Additionally, we attempt to understand the societal implications of water quality, public perception, and environmental investment on natural ecosystems. Forest cover and water body data were obtained from the Corine land cover database, while water quality and investment were compiled from the Czech Statistical Office. Public perceptions on the Czech FES were collected from a national survey. Between 1990 and 2018, forest cover has increased by 3.94% and water bodies by 7.65%; however, from 2014 to 2018, severe droughts were reported that compromised the availability of surface water, presumably on artificial structures, causing an increase in the occupied area. Regarding public perception, respondents with less education, and the older population, obtained an assessment of the low performance of the FES, while the water quality and investment indicate that environmental funding has contributed to improving the quality of outflow water from the wastewater treatment plants, fulfilling all the allowed limits of the urban wastewater treatment directive. Hence, a multidisciplinary approach can help decision makers promote policies that integrate environmental management measures, investment protection, and contribute to sustainable development. Full article

The availability of global digital elevation models (DEMs) from multiple time points allows their combination for analysing vegetation changes. The combination of models (e.g., SRTM and TanDEM-X) can contain errors, which can, due to their synergistic effects, yield incorrect results. We used a high-resolution LiDAR-derived digital surface model (DSM) to evaluate the accuracy of canopy height estimates of the aforementioned global DEMs. In addition, we subtracted SRTM and TanDEM-X data at 90 and 30 m resolutions, respectively, to detect deforestation caused by bark beetle disturbance and evaluated the associations of their difference with terrain characteristics. The study areas covered three Central European mountain ranges and their surrounding areas: Bohemian Forest, Erzgebirge, and Giant Mountains. We found that vertical bias of SRTM and TanDEM-X, relative to the canopy height, is similar with negative values of up to −2.5 m and LE90s below 7.8 m in non-forest areas. In forests, the vertical bias of SRTM and TanDEM-X ranged from −0.5 to 4.1 m and LE90s from 7.2 to 11.0 m, respectively. The height differences between SRTM and TanDEM-X show moderate dependence on the slope and its orientation. LE90s for TDX-SRTM differences tended to be smaller for east-facing than for west-facing slopes, and varied, with aspect, by up to 1.5 m in non-forest areas and 3 m in forests, respectively. Finally, subtracting SRTM and NASA DEMs from TanDEM-X and Copernicus DEMs, respectively, successfully identified large areas of deforestation caused by hurricane Kyril in 2007 and a subsequent bark beetle disturbance in the Bohemian Forest. However, local errors in TanDEM-X, associated mainly with forest-covered west-facing slopes, resulted in erroneous identification of deforestation. Therefore, caution is needed when combining SRTM and TanDEM-X data in multitemporal studies in a mountain environment. Still, we can conclude that SRTM and TanDEM-X data represent suitable near global sources for the identification of deforestation in the period between the time points of their acquisition. Full article

The population dynamics of Hazel Grouse were studied by presence/absence recording at stationary sites along fixed routes (110 km) in the central part of Šumava (Bohemian Forest, Czech Republic) from 1972 to 2019. The 100 km² study area covered altitudes between 600 m (Rejštejn) and 1253 m above sea level (Mt. Sokol). Our database contained indices of Hazel Grouse occupancy: positive sites/visited sites for a yearly increasing number of Hazel Grouse occurrence sites (n = 134) for 48 years. We used a loglinear Poisson regression method to analyze the long-term population trend for Hazel Grouse in the study area. In the period from 1972 to 2006 we found a stable Hazel Grouse population (p = 0.83). From 2006–2007 to 2019, the population index dropped (−3.8% per year, p < 0.05). This decline is assumed to be influenced by habitat loss due to succession, resulting in older, more open forest stands, by strongly increasing forestry and windstorm “Kyrill”, followed by clear cutting, bark beetle damage, and the removal of pioneer trees in spruce plantations, which diminished buds and catkins, the dominant winter food of Hazel Grouse. The influence of disturbance by increasing tourist activities and/or predation is also discussed. Our results could help to optimize the conservation efforts for Hazel Grouse in the Bohemian Forest. Full article

Research highlights: Recreation value increases with the age of replanted as well as successional forests. Successional forests are not systematically less valuable for recreation than replanted forests. Succession may be used as a viable and low-cost reclamation practice of spoil heaps. Background and objectives: Afforestation has been a popular practice in post-mining land reclamation in the Czech Republic. To expand the current evidence on the recreation values of reclaimed forests, we conducted a valuation study for most typical reclaimed forests, as well as for successional forests spontaneously growing on surface coal mine deposit heaps. Using two distinct measurement methods, we also explore whether the estimated recreation value of forests is robust. Materials and Methods: An online survey was conducted in 2016 on a sample of residents living in the vicinity of coal mine deposit heaps, residents of the adjacent region of Karlovy Vary, and a control population from the central Bohemian region. Participants evaluated visual representations of forest stands typical for reclamation and succession, along with commercial spruce forest as a reference type. In the direct measurement, we measured the attractiveness of a respective forest for a walk using a 5-point scale. In the indirect measurement, a hypothetical choice between two forests for a walk was elicited in a discrete choice experiment. Results: Both direct and indirect measurements provide similar results. All reclaimed forests have a lower recreation value than the reference spruce forest. Successional forests are not systematically less valuable for recreation than replanted forests and the recreation value of both types increases with their age. The age, gender, and education of the participants did not affect the recreation value of a forest. Conclusions: We demonstrate that succession may be used as a viable and low-cost reclamation practice of spoil heaps emerging as a by-product of open-cast coal mining. With recreation as only one of many forest uses, our findings need to be interpreted vis-à-vis the objectives and expected results for individual sites and their habitat conditions. Full article

Research Highlights: Differentiation of Scots pine forests of the class Vaccinio-Piceetea in Poland has been the subject of numerous studies, including revisions. Despite that, the area of southwestern Poland was hitherto practically unexplored in this respect. Background and Objectives: The aim of this work was therefore (i) to present the diversity of the pine forests in the Sudetes and their foreland; (ii) to compare the ecology of studied communities. Materials and Methods: We analyzed 175 phytosociological relevés collected between 1991 and 2020 in natural and anthropogenic pine stands. To identify vegetation types, we used the modified TWINSPAN algorithm; principal coordinate analysis, distance-based redundancy analysis and permutational tests were applied to identify the variation explained and the main environmental gradients shaping the studied plant communities. Results: Five associations were distinguished: thermophilous Asplenio cuneifolii-Pinetum sylvestris Pišta ex Husová in Husová et al. 2002, which develops on shallow soils over ultrabasic substrates, Hieracio pallidi-Pinetum sylvestris Stöcker 1965, which prefers outcrops of acidic rocks; Betulo carpaticae-Pinetum sylvestris Mikyška 1970, which is relict in origin and occurs on the upper Cretaceous sandstones, the peatland pine–birch forests of the Vaccinio uliginosi-Betuletum pubescentis Libbert 1933 and the Vaccinio myrtilli-Pinetum sylvestris Juraszek 1928. Moreover, community Brachypodium sylvaticum-Pinus sylvestris with the occurrence of many thermophilous and basiphilous species was also found on limestone substratum. The analysis of the species composition of pine plantations established on deciduous and mixed forests habitats revealed that these anthropogenic communities were marked by a random combination of species in which a certain group of common forest generalists participated. The distinguished communities differed clearly among each other also in habitat characteristics. Particularly important for their differentiation were soil reaction and nutrients, supported by differences in moisture, temperature and light availability. Apart from the edaphic factors, altitude and the bedrock type proved to be equally important. Conclusions: Our study provides new remarks to the typology and synecology of pine forest communities in SW Poland. Full article

This paper explores the potential of the joint application of unmanned aerial vehicle (UAV)-based photogrammetry and an automated sensor network for building a hydrodynamic flood model of a montane stream. UAV-based imagery was used for three-dimensional (3D) photogrammetric reconstruction of the stream channel, achieving a resolution of 1.5 cm/pixel. Automated ultrasonic water level gauges, operating with a 10 min interval, were used as a source of hydrological data for the model calibration, and the MIKE 21 hydrodynamic model was used for building the flood model. Three different horizontal schematizations of the channel—an orthogonal grid, curvilinear grid, and flexible mesh—were used to evaluate the effect of spatial discretization on the results. The research was performed on Javori Brook, a montane stream in the Sumava (Bohemian Forest) Mountains, Czech Republic, Central Europe, featuring a fast runoff response to precipitation events and that is located in a core zone of frequent flooding. The studied catchments have been, since 2007, equipped with automated water level gauges and, since 2013, under repeated UAV monitoring. The study revealed the high potential of these data sources for applications in hydrodynamic modeling. In addition to the ultra-high levels of spatial and temporal resolution, the major contribution is in the method’s high operability, enabling the building of highly detailed flood models even in remote areas lacking conventional monitoring. The testing of the data sources and model setup indicated the limitations of the UAV reconstruction of the stream bathymetry, which was completed by the geodetic-grade global navigation satellite system (GNSS) measurements. The testing of the different model domain schematizations did not indicate the substantial differences that are typical for conventional low-resolution data, proving the high reliability of the tested modeling workflow. Full article