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The Mirambel woodland on the margins of the Millevaches plateau (Massif Central) is one of the few ancient broad-leaved woodlands in France. Historical sources show that it has occupied the same surface area for the past 250 years, despite being in a region that underwent considerable anthropogenic changes during this period. We explored the Mirambel's Holocene history and ancientness by means of soil charcoal analysis, chosen because of its high accuracy on a local scale. We excavated five pedoanthracological pits in the woodland and its open marginal spaces. The 29 radiocarbon dates ranged from the Atlantic (8700–5500 cal yr. BP) – Subboreal transition to the Subboreal (5500–2800 cal yr. BP) and Subatlantic (2800–0 cal yr. BP, i.e. AD 1950) periods, revealing the existence of fire events corresponding to six contemporaneous cultural periods: Neolithic (ca. 3877–2991 cal yr BC), Neolithic-Chalcolithic transition (ca. 2528–2525 cal yr BC), Protohistory (ca. 147 cal yr BC), Roman period (ca. 326–579 cal AD), Middle Ages (ca. 732–1187 cal AD), and contemporary times (ca. 1781 cal AD to present day). Three Tilia charcoal fragments dating from ca. 3717–2919 cal yr BC indicated the presence of a diversified Mid-Holocene deciduous woodland featuring Tilia and Acer nowadays-absent taxa in this area. Deciduous Quercus and Fagus sylvatica dominated most of the soil profiles, as they do nowadays in the woodlands. Other taxa (Salix, Corylus avellana, Betula) were identified, as well as in the current vegetation. The occurrence of Cytisus-type (Fabaceae) and Calluna vulgaris suggested that there were forest clearing phases at all the points sampled. Widely varying levels of abundances may reflect differences in the duration of these open phases.

Wood use in bio-building should be considered as one of the main pillars of sustainability. According to international standards, beech wood (Fagus sylvatica L.) is a rather less durable species as it is subject to degradation due to weathering, though it is abundantly available to a more intense use. Service life of beech products and wood products in general can be enhanced by different methods, such as heat treatments, but new chances are offered by coating technologies. However, to ensure protection from wood-destroying organisms, most commercial coatings include components that could harm human health, other organisms and the environment. Therefore, coating industry has to develop more eco-friendly solutions in order to decrease its impact on human health and environment. The objective of this article was to modify commercial acrylic varnish by adding cellulose nanocrystals (CNC) and lignin (LN) extracted from beech wood and investigate their effect on water sorption, additive dispersion in the coating matrix and coating resistance to bacterial attack. Contact angle, weight gain and colour difference were analysed and FT-IR mapping was applied. The performance of CNC was promising, as it enhanced water sorption of the modified coating. However, protection against bacterial attack was not satisfying. On the other hand, chemically unmodified lignin did not show positive effects as component in the coating formulation. Nevertheless, the currently limited usage of these two renewable and abundant resources urgently calls for their more efficient utilization, in order to create additional value with industry side-streams producing novel bio-based materials. Further experiments are needed in order to obtain better dispersion of the particles and higher resistance to bacterial attacks.

Intra-seasonal growth responses of co-occurring European beech (Fagus sylvatica L.) and Norway spruce (Picea abies (L.) Karst.) to weather variability in montane forests can provide useful information on their future growth trends. To improve growth predictions, we aimed to identify (i) the main seasonal windows during which weather variability influences tree-ring growth, (ii) species-specific differences in the response to weather fluctuations, and (iii) teleconnections to remote sites in the Western Carpathians. We monitored intra-seasonal growth dynamics based on proxies extracted growth signals detected by high-resolution dendrometers in the transition zone between the beech and spruce altitudinal belt. Over 12 consecutive seasons in the natural montane forest (1350 m a.s.l.), the main part of spruce (68% to 10 July) and beech (95% to 26 August) annual increment was under the prevailing influence of temperature. After this, precipitation pattern (regarding spruce) and day length became the most influential variables during deceleration and cessation of growth. In addition, synchronous patterns with remote sites in the Western Carpathians were found. The results emphasize the importance of studying the influence of shorter-term weather fluctuations during the season. Our findings suggest that montane spruce tends to be less temperature-demanding and more drought-sensitive than beech, which may favor beech over the spruce under the future climate.

Leaf morphological and physiological traits control the carbon and water relations of mature trees and are determinants of drought tolerance, but it is not well understood how they are modified in response to water deficits. We analysed five sun-canopy leaf traits (mean leaf size (LS), specific leaf area (SLA), Huber value (HV), water potential at turgor loss point (Ψtlp ) and foliar carbon isotope signature (δ13 C)) in European beech (Fagus sylvatica L.) across three precipitation gradients sampled in moist (2010), dry (2019) and very dry (2018) summers, and tested their response to short-term water deficits (climatic water balance (CWB) preceding sample collection) and long-term water availability (mean annual precipitation (MAP), plant-available soil water capacity (AWC) and neighbourhood competition). Across the 34 sites, LS varied seven-fold (3.9-27.0 cm2 ), SLA four-fold (77.1-306.9 cm²·g-1 ) and HV six-fold (1.0-6.65 cm2 ·m-2 ). In the 2018 dataset, LS showed a negative and HV a positive relationship to MAP, which contradicts relations found in multi-species samples. Average Ψtlp ranged from -1.90 to -2.62 MPa and decreased across the sites with decreasing CWB in the month prior to measurement, as well as with decreasing MAP and AWC in 2019. Studied leaf traits varied considerably between years, suggesting that mast fruiting and the severe 2018 drought caused the formation of smaller leaves. We conclude that sun-canopy leaf traits of European beech exhibit considerable plasticity in response to climatic and edaphic aridity, and that osmotic adjustment may be an important element in the drought response strategy of this anisohydric tree species.

Using hierarchical clustering with unweighted pair-group method with arithmetic mean (UPGMA) we arranged 602 phytosociological releves of beech forests on the present forest line, mainly from the Julian Alps and the Trnovo Forest Plateau (we also included the releves from the Karawanks and the Kamnik Alps) into 32 clusters. Based on their analysis and comparison with previously described similar (alti)montane-subalpine beech communities we classified most of the releves into the association Polysticho lonchitis-Fagetum and its new subassociations ericetosum carneae, cardaminetosum trifoliae, luzuletosum niveae, luzuletosum luzuloidis, calamagrostieteosum variae, allietosum victorialis, adoxetosum moschatellinae, stellarietosum nemorum and several new variants. The altitude of the studied stands is predominantly 1400 to 1550 m (the upper line is at 1660 m); they occur at all aspects, frequently on steep and very steep slopes, mainly on limestone and dolomite limestone, the predominant soil type is rendzina. These stands are species rich (on average 61 species per releve, altogether more than 500 vascular plants) and have many species in common with the stands of associations Rhododendro hirsuti-Fagetum and Rhodothamno-Laricetum. They belong to the habitat type of Community interest 91K0 Illyrian Fagus sylvatica forests and are some of the best preserved forest communities in the Southeastern Alps and northwestern Dinaric Alps, comprising small areas of virgin forest remnants and performing an important protective role as a biotope.

This paper presents a thermal characterization of hardwoods of Hungarian origin. The study covers the wood of the following tree species: sessile oak (Quercus petraea), beech (Fagus sylvatica), hornbeam (Carpinus betulus), black locust (Robinia pseudoacacia), lime (Tilia platyphyllos), ash (Fraxinus ornus), maple (Acer campestre), alder (Alnus glutinosa), and aspen (Populus tremula). Wood samples were subjected to differential scanning calorimetry and thermogravimetry in an air atmosphere at different heating rates of 10, 20, and 40 °C·min−1. The activation energy was calculated using the Flynn–Wall–Ozawa method. Thermogravimetric analysis revealed that tree species differed considerably in the mass loss and the temperature of the maximum mass loss rate related to the thermal degradation of the main wood components and the oxidation of char mainly derived from lignin. Beech, hornbeam and ash were characterized by a high mass loss attributed to decomposition of hemicelluloses. The mass loss assigned to the thermal degradation of cellulose varied from 35.41% (ash wood) to 53.65% (alder wood). Sessile oak wood showed the greatest mass loss and the highest temperature of thermoxidation of residual lignin and char. Calorimetrically measured values of the exothermic effect of the wood thermal degradation were in the range 7.93–9.65 kJ g−1. The average values of activation energy for the thermal degradation of carbohydrates and the thermoxidation of residual lignin and char were found to be 176.0 ÷ 197.3 kJ mol−1and 196.4 ÷ 319.5 kJ mol−1, respectively.

Low mortality rates and slow growth differentiate shade-tolerant from shade-intolerant species and define the survival strategy of juvenile trees growing in deep shade. While radial stem growth has been widely used to explain mortality in juvenile trees, the leaf area ratio (LAR), known to be a key component of shade tolerance, has been neglected so far. We assessed the effects of LAR, radial stem growth and tree height on survival time and the age-specific mortality rate of juvenile Fagus sylvatica L. (European beech), Acer pseudoplatanus L. (sycamore maple) and Acer platanoides L. (Norway maple) in a primeval beech forest (Ukraine). Aboveground and belowground biomass and radial stem growth were analysed for 289 living and 179 dead seedlings and saplings. Compared with the other species, F. sylvatica featured higher LAR, slower growth and a lower mortality rate. The average survival time of F. sylvatica juveniles (72 years) allows it to reach the canopy more often than its competitors in forests with low canopy turnover rate. In contrast, a combination of lower LAR, higher growth rate and higher age-specific mortality rate of the two Acer species resulted in their shorter survival times and thus render their presence in the canopy a rare event. Overall, this study suggests that shade tolerance, commonly defined as a relationship between sapling mortality and growth, can alternatively be formulated as a relationship between survival time and the interplay of growth and LAR.

The effects of microwave and steam treatment were analyzed relative to the immediate (thermo-hygro-plasticity) and post-assessed (permanent changes) properties of wood. The study was conducted using European beech (Fagus sylvatica L.) standard and 1.5 times up-scaled (only for microwave-heated and reference samples) bending specimens tested in a static three-point loading mode. The specimens were plasticized by heat and moisture (1) separately and (2) simultaneously by heating moist specimens using (i) various microwave regimes in continuous mode, and (ii) heated saturated steam in discontinuous mode. Oven-dried specimens tested at 20 degrees C served as references. The thermo-hygro-plasticity was studied immediately after treatment, whereas the permanent changes were assessed after oven-drying of plasticized specimens to 0% moisture content. Permanent structural changes were analyzed using scanning electron microscopy. Microwave treatment increased the plasticity of wood (decreasing the modulus of elasticityby 70%) comparably to steam treatment, when the output moisture content was 30% or higher. A similar degree of plasticity was found in up-scaled specimens heated by microwaves. Further analyses confirmed that microwave treatment did not cause any permanent damage to wood structure or reduce mechanical performance. The results showed that microwave treatment is an efficient alternative to steaming when plasticizing moist wood.

Leaf shape in European beech provenances varies geographically, with narrower and longer lamina observed in southern provenances, indicating a direct selection favoring leaf shape that likely safeguards trees performances under less favorable growing conditions. Spatial and environmental patterns of European beech (Fagus sylvatica L.) leaf size and shape variations were studied using landmark-based geometric morphometrics. The study involved eight provenances originating from three biogeographic regions (i.e., Alpine, Continental, and Pannonian), spanning across six European countries (Bosnia and Herzegovina, Croatia, Germany, Hungary, Romania and Serbia). All specimens were cultivated in a common garden experiment. The symmetric component of leaf shape variation was analyzed by Procrustes ANOVA and multi‐variate analyses [principal component analysis and canonical variate analysis (CVA)], whereas MANOVA was used to examine asymmetry. Partial least square (PLS) analysis was used to assess the covariation between leaf shape and size, and geographical position and environmental variables at the sites of provenance origin, respectively. A highly observed phenotypic variation for the shape and size of leaf both within and among provenances, indicates a strong local adaptation of provenances within the species natural range. CVA revealed the existence of two clusters of provenances based on the leaf shape, i.e., the first group included provenances originating from Balkan Peninsula and Central Europe, while the second group consisted of two Romanian provenances and the northernmost provenance from Germany. Likewise, PLS evidenced that leaf shape was spatially structured along latitudinal (− 0.64) and longitudinal (0.60) gradients, with southern provenances having longer and narrower (ovate) lamina compared to the northern ones. In contrast, no correlation was found between centroid size and spatial and environmental variables. Results suggest the presence of direct selection favoring a leaf shape that likely safeguards trees from heat and water loses under less favorable growing conditions.

This study was carried out to investigate the population status and ecology of the moss Codonoblepharon forsteri (Dicks.) Goffinet (syn. Zygodon forsteri (Dicks.) Mitt.) at Burnham Beeches, UK.Popu...

Aim: Ongoing climate warming has been widely reported to delay autumn phenology, which in turn impacts carbon, water, energy and nutrient balances at regional and global scales. However, the underlying mechanisms of autumn phenology responses to climate change have not been fully elucidated. The aims of this study were to determine whether brightening that was defined as the increase of surface solar radiation and warming during recent decades affect autumn phenology in opposite directions and explore the underlying mechanisms. Location: Central Europe. Time period: 1950–2016. Major taxa studied: Four dominant European tree species in central Europe: Aesculus hippocastanum, Betula pendula, Fagus sylvatica and Quercus robur. Methods: We investigated the temporal trends of leaf senescence, preseason temperature and radiation by separating the period of 1950–2016 into two sub-periods (1950–1982 and 1983–2016) and determined the relationship between temperature, radiation and leaf senescence using partial correlation analysis. Results: We found a significant warming and brightening trend after the 1980s in central Europe, yet this led to only slight delays in leaf senescence that cannot be explained by the well-known positive correlation between leaf senescence and autumn warming. Interestingly, we found opposite effects between warming (partial correlation coefficient, r =.37) and brightening (r = −.23) on leaf senescence. In addition, the temperature sensitivity of leaf senescence decreased with increasing radiation (−5.08 days/℃/108 J/m2). Main conclusions: The results suggested that brightening accelerated the leaf senescence dates, counteracting the warming-induced delays in leaf senescence, which may be attributed to photooxidative stress and/or sink limitation. This emphasizes the need to consider radiation to improve the performance of autumn phenology models.

N and P are essential macronutrients for all organisms. How shifts in the availability of N or P affect fungal communities in temperate forests is not well understood. Here, we conducted a factorial P × N fertilization experiment to disentangle the effects of nutrient availability on soil-residing, root-associated, and ectomycorrhizal fungi in beech (Fagus sylvatica) forests differing in P availability. We tested the hypotheses that in P-poor forests, P fertilization leads to enhanced fungal diversity in soil and roots, resulting in enhanced P nutrition of beech, and that N fertilization aggravates P shortages, shifting the fungal communities toward nitrophilic species. In response to fertilizer treatments (1 × 50 kg ha−1 P and 5 × 30 kg ha−1 N within 2 years), the labile P fractions increased in soil and roots, regardless of plant-available P in soil. Root total P decreased in response to N fertilization and root total P increased in response to P addition at the low P site. Ectomycorrhizal species richness was unaffected by fertilizer treatments, but the relative abundances of ectomycorrhizal fungi increased in response to P or N addition. At the taxon level, fungal assemblages were unaffected by fertilizer treatments, but at the order level, different response patterns for saprotrophic fungi among soil and ectomycorrhizal fungi on roots were found. Boletales increased in response to P, and Russulales decreased under N + P addition. Our results suggest that trait conservatism in related species afforded resistance of the resident mycobiome composition to nutritional imbalances.

Територія Національного природного парку "Зачарований край" розташована в центральній частині Вигорлат-Гутинської Вулканічної гряди (передгір'я Східних Карпат) і на 96,7 % представлена лісовими землями. У породному складі явним домінантом є бук європейський (Fagus sylvatica L.) ‒ 92 %, на другому місці ялина європейська (Picea abies (L.) H. Karst.) ‒ 6,6 %, на решту порід припадає 1,4 % від площі вкритих лісовою рослинністю лісових ділянок. Регулярне вивчення стану насаджень на територіях природно-заповідного фонду ‒ одне із завдань, покладених на науковий відділ Національного природного парку "Зачарований край". Оцінювання санітарного стану здійснювали переважно у літні місяці (липень-вересень) 2020 р. на дев'яти кругових постійних пробних площах, з використанням відповідних методик. Встановлено, що деревостани (зважаючи на санітарний стан ялини загалом) за індексом санітарного стану є дуже ослабленими ‒ участь ялини у складі 3-4 одиниці, всихаючими ‒ 7-8 одиниць, всохлими ‒ 9-10 одиниць. За ступенем деградації фотосинтетичного апарату деревостани з участю ялини у складі 3-4 та 7 одиниць належать до класу "середньо ушкоджені", а деревостани з участю ялини у складі 8-10 одиниць – переважно до класу "дуже ушкоджені". Середня частка сухостійної деревини в загальному запасі збільшилася за 10-річний період від 2,9 до 37,8 %. При цьому середня частка сухостійної деревини у змішаних деревостанах становить 21,8 %, а у чистих та з переважанням участі ялини (8 і 9 одиниць) ‒ 45,8 %. Виявлено, що середня частка сухостійних дерев на пробних площах становить 63,5 % ‒ від кількості дерев ялини та 44,6 % ‒ від загальної кількості дерев. Середня частка сухостійних дерев у змішаних деревостанах становить 29,1 %, а у чистих та з участю ялини 9 і 8 одиниць ‒ 53,1 %. Масове всихання ялини призвело до переходу більшості деревостанів ялини, за елементом лісу, у всохлі насадження. Основними причинами деградації ялинових деревостанів є осередки короїдів та абіотичні чинники (вітровали та буреломи), що призвели до механічних пошкоджень стовбурів.

Mast seeding, the synchronized interannual variation in seed production of trees, is a well‐known bottom‐up driver for population densities of granivorous forest rodents. Such demographic effects also affect habitat preferences of the animals: After large seed production events, reduced habitat selectivity can lead to spillover from forest patches into adjacent alpine meadows or clear‐cuts, as has been reported for human‐impacted forests. In unmanaged, primeval forests, however, gaps created by natural disturbances are typical elements, yet it is unclear whether the same spillover dynamics occur under natural conditions. To determine whether annual variation in seed production drives spillover effects in naturally formed gaps, we used 14 years of small mammal trapping data combined with seed trap data to estimate population densities of Apodemus spp. mice and bank voles (Myodes glareolus) on 5 forest sites with differing disturbance history. The study sites, located in a forest dominated by European beech (Fagus sylvatica), Norway spruce (Picea abies), and silver fir (Abies alba), consisted of two primeval forest sites with small canopy gaps, two sites with larger gaps (after an avalanche event and a windthrow event), and a managed forest stand with closed canopy as a control. Hierarchical Bayesian N‐mixture models revealed a strong influence of seed rain on small rodent abundance, which were site‐specific for M. glareolus but not for Apodemus spp. Following years of moderate or low seed crop, M. glareolus avoided open habitat patches but colonized those habitats in large numbers after full mast events, suggesting that spillover events also occur in unmanaged forests, but not in all small rodents. The species‐ and site‐specific characteristics of local density responding to food availability have potentially long‐lasting effects on forest gap regeneration dynamics and should be addressed in future studies., We present novel hierarchical Bayesian N‐mixture models of unique count data from 14 years of small mammal live trapping investigating functional responses of dominant rodent taxa to different habitat types and mast seeding, including sites of natural disturbance events and sites in the largest remaining primeval forest of the Alps.

A recent paper by Schall et al. (2020) concluded that beech forests managed in even-aged (EA) rotation systems were more efficient than unmanaged (UNM) forest and forest managed in uneven-aged (UEA) selective cutting systems in supporting landscape-scale biodiversity in Germany. The authors based their conclusion on a comprehensive multitaxon survey and a promising resampling model for assessing gamma diversity at landscape scale. Here, we challenge their conclusions and evaluate the importance of UNM forests for conservation of forest biodiversity. The average amount of dead wood reported from EA stands (27.8 m3/ha) was almost 30% higher than reported from UNM stands (21.6 m3/ha) in the study. Averages from long UNM temperate forests in Europe are typically six to seven times higher (131–157 m3/ha). We therefore conclude the UNM studied stands to reflect legacies of former management, and to be poorly representative of UNM forests. Data from our own studies, including long UNM beech stands in Denmark, demonstrate how this shortcoming seriously undermines the general validity of the presented results to conservation of forest biodiversity. Synthesis and applications. Preservation and restoration of intact forest ecosystems remains essential to biodiversity conservation. We show that the findings of Schall et al. (2020) do not contradict this important notion. Schall and colleagues identified UEA management systems as potentially inferior to more traditional EA management systems for conserving forest biodiversity at the landscape scale. The paper also provides insight into the limited short-term conservation value of simply abandoning forest management in intensively managed landscapes. Based on this, we call for discarding the current orthodox view of non-intervention when new forest reserves are created in temperate Europe. Active reinforcement of natural disturbance regimes and active habitat creation may lead to faster recovery of natural stand structure and forest biodiversity.

High genetic variation and extensive gene flow may help forest trees with adapting to ongoing climate change, yet the genetic bases underlying their adaptive potential remain largely unknown. We investigated range-wide patterns of potentially adaptive genetic variation in 64 populations of European beech (Fagus sylvatica L.) using 270 SNPs from 139 candidate genes involved either in phenology or in stress responses. We inferred neutral genetic structure and processes (drift and gene flow) and performed differentiation outlier analyses and gene-environment association (GEA) analyses to detect signatures of divergent selection.Beech range-wide genetic structure was consistent with the species’ previously identified postglacial expansion scenario and recolonization routes. Populations showed high diversity and low differentiation along the major expansion routes. A total of 52 loci were found to be putatively under selection and 15 of them turned up in multiple GEA analyses. Temperature and precipitation related variables were equally represented in significant genotype-climate associations. Signatures of divergent selection were detected in the same proportion for stress response and phenology-related genes. The range-wide adaptive genetic structure of beech appears highly integrated, suggesting a balanced contribution of phenology and stress-related genes to local adaptation, and of temperature and precipitation regimes to genetic clines. Our results imply a best-case scenario for the maintenance of high genetic diversity during range shifts in beech (and putatively other forest trees) with a combination of gene flow maintaining within-population neutral diversity and selection maintaining between-population adaptive differentiation.

The impact of forest management on biodiversity is difficult to scrutinize along gradients of management. A step towards analyzing the impact of forest management on biodiversity is comparisons between managed and primary forests. The standardized typology of tree-related microhabitats (TreMs) is a multi-taxon indicator used to quantify forest biodiversity. We aim to analyze the influence of environmental factors on the occurrence of groups of TreMs by comparing primary and managed forests. We collected data for the managed forests in the Black Forest (Germany) and for the primary forests in the Western (Slovakia) and Southern Carpathians (Romania). To model the richness and the different groups of TreMs per tree, we used generalized linear mixed models with diameter at breast height (DBH), altitude, slope and aspect as predictors for European beech (Fagus sylvatica (L.)), Norway spruce (Picea abies (L.)) and silver fir (Abies alba (Mill.)) in primary and managed temperate mountain forests. We found congruent results for overall richness and the vast majority of TreM groups. Trees in primary forests hosted a greater richness of all and specific types of TreMs than individuals in managed forests. The main drivers of TreMs are DBH and altitude, while slope and aspect play a minor role. We recommend forest and nature conservation managers to focus: 1) on the conservation of remaining primary forests and 2) approaches of biodiversity-oriented forest management on the selection of high-quality habitat trees that already provide a high number of TreMs in managed forests based on the comparison with primary forests.

Ectomycorrhizal plants trade plant-assimilated carbon for soil nutrients with their fungal partners. The underlying mechanisms, however, are not fully understood. Here we investigate the exchange of carbon for nitrogen in the ectomycorrhizal symbiosis of Fagus sylvatica across different spatial scales from the root system to the cellular level. We provided 15N-labelled nitrogen to mycorrhizal hyphae associated with one half of the root system of young beech trees, while exposing plants to a 13CO2 atmosphere. We analysed the short-term distribution of 13C and 15N in the root system with isotope-ratio mass spectrometry, and at the cellular scale within a mycorrhizal root tip with nanoscale secondary ion mass spectrometry (NanoSIMS). At the root system scale, plants did not allocate more 13C to root parts that received more 15N. Nanoscale secondary ion mass spectrometry imaging, however, revealed a highly heterogenous, and spatially significantly correlated distribution of 13C and 15N at the cellular scale. Our results indicate that, on a coarse scale, plants do not allocate a larger proportion of photoassimilated C to root parts associated with N-delivering ectomycorrhizal fungi. Within the ectomycorrhizal tissue, however, recently plant-assimilated C and fungus-delivered N were spatially strongly coupled. Here, NanoSIMS visualisation provides an initial insight into the regulation of ectomycorrhizal C and N exchange at the microscale.

Being able to persist in deep shade is an important characteristic of juvenile trees, often leading to a strong dominance of shade-tolerant species in forests with low canopy turnover and a low disturbance rate. While leaf, growth, and storage traits are known to be key components of shade tolerance, their interplay during regeneration development and their influence on juveniles' survival time remains unclear. We assessed the ontogenetic effects of these three traits on the survival time of beech (Fagus sylvatica), and Norway and sycamore maples (Acer pseudoplatanus, Acer platanoides) in a primeval beech forest. Biomass allocation, age, and content of nonstructural carbohydrates (NSC) were measured in the stems and roots of 289 seedlings and saplings in high- and low-vitality classes. Saplings experienced a trade-off between absolute growth rate (AGR) and storage (NSC) as the leaf area ratio (LAR) decreases with biomass development. High LAR but low AGR and low NSC corresponded to beech with a marked ability to persist in deep shade while awaiting canopy release. In turn, a comparably small LAR in combination with a high AGR and higher storage (NSC), as observed in Norway maple and sycamore maple, reduced sapling survival time, thus offering an explanation for beech dominance and maple disappearance in the undergrowth of old-growth beech forests., Ecology and Evolution, 11 (15), ISSN:2045-7758

Atmospheric deposition of nitrogen (N) has exceeded its demand for plant increment in forest ecosystems in Germany. High N inputs increased plant growth, the internal N cycling within the ecosystem, the retention of N in soil and plant compartments, and the N output by seepage water. But the processes involved are not fully understood, notably the effect of fructification in European beech (Fagus sylvatica L.) on N fluxes. The frequency of fructification has increased together with air temperature and N deposition, but its impact on N fluxes and the sequestration of carbon (C) and N in soils have been hardly studied. A field experiment using 15 N-labeled leaf litter exchange was carried out over a 5.5-year period at seven long-term European beech (Fagus sylvatica L.) monitoring sites to study the impact of current mast frequency on N cycling. Mean annual leaf litterfall contained 35 kg N ha −1 , but about one-half of that was recovered in the soil 5.5 years after the establishment of the leaf litter 15 N exchange experiment. In these forests, fructification occurred commonly at intervals of 5 to 10 years, which has now changed to every 2 years as observed during this study period. Seed cupules contributed 51 % to the additional litterfall in mast years, which creates a high nutrient demand during their decomposition due to the very high ratios of C to N and C to phosphorus (P). Retention of leaf litter 15 N in the soil was more closely related to the production of total litterfall than to the leaf litterfall, indicating the role of seed cupules in the amount of leaf N retained in the soil. Higher mast frequency increased the mass of mean annual litterfall by about 0.5 Mg ha −1 and of litterfall N by 8.7 kg ha −1 . Mean net primary production (NPP) increased by about 4 %. Mean total N retention in soils calculated by input and output fluxes was unrelated to total litterfall, indicating that mast events were not the primary factor controlling total N retention in soils. Despite reduced N deposition since the 1990s, about 5.7 out of 20.7 kg N ha −1 deposited annually between 1994 and 2008 was retained in soils, notably at acid sites with high N / P and C / P ratios in the organic layers and mineral soils, indicating P limitation for litter decomposition. Trees retained twice as much N compared to soils by biomass increment, particularly in less acidic stands where the mineral soils had low C / N ratios. These results have major implications for our understanding of the C and N cycling and N retention in forest ecosystems. In particular the role of mast products in N retention needs more research in the future.

Complex detailed analysis—3D extension of tension wood, Anatomical intensity and tree-ring eccentricity—of one Fagus sylvatica L. individual provides unique insight into tree growth response to landsliding Compression wood formation and tree ring eccentricity of coniferous trees have often been used to date past geomorphic events because of their well-defined tree ring boundaries and visible reaction wood. On the other hand, complex analysis of the ability of tree rings and anatomy of broadleaved trees to detect past geomorphic events is rather rare. Although analysis of broadleaved trees has some limitations, a combination of both approaches (tree ring anatomy and eccentricity) can provide a suitable dendrogeomorphological tool for dating and understanding past landslide events. From an example of a young Fagus sylvatica L. individual, vertical variability of growth responses in the whole stem was detected. The sampled individual was tilted as a direct response to a landslide event caused by intense rainfall in July 1997. It was found that the growth responses of the sampled individual varied with increasing height. By analysing 14 cross sections in the tree stem, it was detected that the sampled individual started to form tension wood (TW) immediately in 1997. This response was also confirmed by the decrease of the vessel lumen area (VLA). The largest decrease of the VLA was in axes A and D. As a result of TW formation, the sampled individual started to form eccentric tree rings. It was observed that with the increasing height of the tree, the number of tree rings with TW and VLA decreased. The formation of TW and eccentricity, but not VLA, also depends on the stem tilting intensity. According to our experimental results, a combination of both approaches can provide a suitable tool to detect the moment of tree growth responses and therefore date landslide movement events.

Research on the Běleč creeping slope deformation is a contribution to identification of the causes of a breakdown of the water-supply conduit of the Brno regional water-supply network and to ensuring its regular operation. Field geomorphological mapping was used for the research and dendrogeomorphologic methods, especially the method of analysis of tree rings (eccentric tree rings, growth changes), were used for studying the slope failure dynamism. Slope movement activity in the years 1900–2007 was monitored with the help of 45 boring samples. The analysis of tree rings of common beech (Fagus sylvatica) samples did not prove continual movements over the whole extent of the deformation. The present activity is characterized only by local episodic movements of creeping character in the years 1947, 1975, 1993, 1997 a 2006. It was proved that the slope deformation did not have a direct impact on the breakdown of the water-supply conduit in 2005. Využití dendrogeomorfologických metod při výzkumu svahové deformace Běleč, Českomoravská vrchovina (Česká republika) Výzkum hluboce založené plouživé svahové deformace Běleč je příspěvkem k identifikaci příčin vzniku poruchy vodovodního přivaděče Brněnských oblastních vodovodů a zajištění jeho provozu. Při výzkumu poruchy bylo využito geomorfologického mapování a dendrogeomorfologických metod (analýza excentrických letokruhů, růstové změny), které sloužily ke studiu dynamiky svahové poruchy. Aktivita svahových pohybů mezi roky 1900–2007 byla zkoumána pomocí 45 vyvrtaných jádrových vzorků. Analýza letokruhů buku lesního (Fagus sylvatica) neprokázala kontinuální pohyby v celém rozsahu deformace. Současná aktivita je charakteristická spíše lokálními epizodickými pohyby plouživého charakteru v letech 1947, 1975, 1993, 1997 a 2002. Bylo tak prokázáno, že svahová deformace neměla přímý vliv na poruchu vodovodního přivaděče v roce 2005.

The current tendency towards the silvicultural promotion of mixed tree species has increased the variability in the crown structure within stands. This study shows how neighbouring trees can influence both the external crown features and internal wood properties of trees. Using terrestrial laser scanning, the crown features of 100 European beech trees (Fagus sylvatica L.) from pure beech stands and mixed stands of beech with Douglas fir (Pseudotsuga menziesii (Mirb.) Franco), Norway spruce (Picea abies (L.) Karst.), sessile oak (Quercus petraea (Matt.) Liebl.), and Scots pine (Pinus sylvestris L.) were recorded. After felling and sawing, the dynamic modulus of elasticity was determined on 1623 boards from the two lowest 4.1 m logs. Significant differences were found between beech trees from pure stands and those from beech–pine mixed stands in terms of crown volume (415 vs 766 m3), crown ratio (50.0% vs 71.5%), crown projection ratio (0.182 vs 0.253 m·cm−1), and branch angle (30.7° vs 54.1°). Multiple regression mixed models revealed significant relationships between timber stiffness and crown volume (–1.7 N·mm−2·m−3), crown ratio (–28.4 N·mm−2·%−1), and crown projection ratio (–9835 N·mm−2·m−1·cm). Thus, the crown morphology of broad-leaved species reflects the tree’s long-term competitive status and suggests indicators for the assessment of mechanical–physical wood properties.

Background and Aims Many recent studies emphasize that mixed species is a promising silvicultural option for sustainable ecosystem management under uncertain and risky future environmental conditions. However, compared with monocultures, knowledge of mixed stands is still rather fragmentary. This comprehensive study analysed the most common Central European tree species combinations to determine the extent to which mono-layered species mixing (1) can increase stand productivity and stem diameter growth, (2) increase stand density or growth efficiency, and (3) reduce competition and attenuate the relationship between stand density and stem diameter growth compared with mono-specific stands. Methods The study was based on 63 long-term experimental plots in Germany with repeated spatially explicit stand inventories. They covered mono-specific and mixed species stands of Norway spruce (Picea abies), silver fir (Abies alba), Scots pine (Pinus sylvestris), European beech (Fagus sylvatica), sessile oak (Quercus petraea), European ash (Fraxinus excelsior) and sycamore maple (Acer pseudoplatanus). Based on spatially explicit measurement, we quantified for each tree the intra- or inter-specific neighbourhood, local stand density and growth. We applied mixed models to analyse how inter-specific neighbourhoods modify stand productivity, stand density, growth efficiency, individual tree growth and the trade-off between individual tree growth and stand productivity. Key Results We found stand productivity gains of 7–53 % of mixed versus mono-specific stands continuing over the entire rotation. All mixtures achieved a 3–36 % higher leaf area index until advanced stand age. Stem diameter growth increased by up to 31 % in mixed stands. The growth efficiency of the leaf area was up to 31 % higher, except in mixtures of sessile oak and European beech. The trade-off between stem diameter growth and stand productivity was attenuated by the mixture. Conclusions The increased productivity was mainly based on a density increase in the case of Norway spruce/silver fir/European beech and sessile oak/European beech and it was based on a more efficient resource use given the same stand density in the case of Scots pine/European beech and European ash/sycamore maple. In the other species assemblages the increased productivity was based on a combination of density and efficiency increase. We hypothesize that the density effect may be site-invariant and mainly depends on the structural species complementarity. The efficiency increase of growth may depend on the growth-limiting factor that is remedied by mixture and thus be co-determined by the site conditions. For forest management, the results indicate increased stand and tree size growth by species mixing. For the common mixtures examined in this study the results show that thinning for the acceleration of stem growth requires less density reduction and causes less stand growth losses than in monocultures. We discuss the consequences of our findings for silvicultural prescriptions for mixed-species stands.

Based on the laser point clouds of 240 individual trees that were also identified in the field, we developed decision trees to distinguish deciduous and coniferous trees and individual tree species: Picea abies, Larix decidua, Pinus sylvestris, Fagus sylvatica, Acer pseudoplatanus, Fraxinus excelsior. The volume of the upper part of the tree crown (height of 3 m) and the average intensity of the laser reflections were used as explanatory variables. There were four aerial laser datasets: May 2012, September 2012, March 2013 and July 2015. We found that the combination of the volume and the average intensity of the first three laser datasets was the most reliable for predicting the selected tree species (60% model performance). A slightly poorer model performance was obtained if only the average intensity of the first three datasets was used (54% model performance). The worst model performance was given by the intensities (31 % model performance) or the volumes (21 % model performance) of dataset 4, which represents the national laser scanning of Slovenia (LSS). The best performing was the deciduous and coniferous separation, which achieved 75% and 95% success based on the test data (combination of volume and average intensity of the first three laser datasets). Using only the LSS intensities, deciduous and coniferous trees could be separated with 81% success.

As of 2019, the total area of forest stands with the varying proportion of Scots pine (Pinus sylvestris L.) and beech (Fagus sylvatica L.) in composition on the Ukrainian Roztochchia was 11,251.3 ha and the area of pine stands involving European beech in composition was 6879.5 ha. Pine stands involving beech in composition are formed on the fresh, moist and boggy relatively pure and relatively rich soil condition. Pine forest stands (average share of pine exceeds 56%), which include beech in composition occupy more than 80% of the total area of interest. Mature and overmature forest stands dominate most of the landscape. More than 85% of stands are characterized by an average relative completeness. Undergrowth of deciduous tree species, which is mainly formed by European beech or hornbeam (Carpinus betulus L.) and rarely by common oak (Quercus robur L.) or sycamore maple (Acer pseudoplatanus), is available under a canopy of middle-aged, ripening and mature stands. The study points to the need to rethink forest management approaches and eventually to use such methods of forest cuttings that ensure natural regeneration not only of a European beech and common oak, but primarily of a pine. The practice of creating pine plantations in such conditions favourable for its growth and development should be used only in those cases when it is impossible to achieve natural regeneration of pine.

The Žumberak and Samobor highlands are situated in the north-western part of Croatia where the characteristics of the Dinarides, the Alps and the Pannonian Plain meet. The greater part of the area is occupied by beech forests. The aim of the study was to determine the syntaxonomic affiliation of these forest communities, and to explore their floristic and main ecological features. Numerical analyses of floristic compositions were conducted on a data-set consisting of 144 new relevés and 99 relevés from the existing literature. Relevés were made following the standard Braun-Blanquet method. For descriptions of ecological conditions Ellenberg’s indicator values were used. Six plant associations and two subassociations of beech forests were established in Luzulo-Fagion and Aremonio-Fagion alliances. The higher altitudes of the studied area are occupied by ass. Cardamini savensi-Fagetum, whereas the lower altitudes are occupied by ass. Lamio orvalae-Fagetum and Hacquetio-Fagetum. Ass. Hacquetio-Fagetum spreads on southern slopes and ridges, whereas ass. Lamio orvalae-Fagetum occurs in ditches and on northern slopes. In the warmer habitats with shallow soils on a dolomite base ass. Ostryo-Fagetum occurred. A small part of the area is characterized by silicate substrate which is occupied by ass. Luzulo-Fagetum and Gentiano asclepiadeae-Fagetum.

Sustainable Forest Management (SFM) indicators consider the main ecological and socioeconomic functions of forests but do not currently include some key groups widely adopted to assess the effects ...

Decomposition of litter is a key biochemical process that regulates the rate and magnitude of CO2 fluxes from biosphere to atmosphere and determines soil nutrient availability. Although several studies have shown that plant litter decomposition accelerated in their native compared to a foreign environment, that is, a home-field advantage (HFA) for litter degradation, to date HFA has only been considered in terms of respiration or litter mass loss. The competitive success of the decomposer micro-organism will be determined by its ability to transform used OM into population growth. Therefore, we hypothesized that HFA for microbial growth would be more pronounced than that for decomposition. We also expected that HFA effect for decomposition and microbial growth would increase with lower quality litter, which the fungal role in litter decomposition would be more dominant than that of bacteria, and that HFA effects would strengthen with more pronounced differences between ‘home’ and ‘away’ environments. We designed a 2-month microcosm reciprocal transplant experiment with litter from two sites with contrasting climates (Atlantic and Sub-Mediterranean climates) and including three tree species (Quercus robur, Pinus sylvestris and Fagus sylvatica). We found a stronger HFA for microbial growth than for decomposition, that the nutrient content and C-quality of litter influenced the microbial HFA and that interactions between bacterial and fungal communities during litter decomposition modulated the HFA for litter degradation. Low litter nutrient content, strong nutrient limitations and low C-qualities all favoured fungal over bacterial decomposers, and our results suggest a dominant functional role of the fungal community and gave rise to HFA effect for fungal growth but that this translated to only marginal implications for overall decomposition of litter. A free Plain Language Summary can be found within the Supporting Information of this article. (Less)

With progressive climate change, the chemical defense in European beech (Fagus sylvatica L.) is likely to change, which might impact its fitness and ability to establish beyond its current northern distribution limit. We studied the phenolic defense in six beech provenances grown in three common gardens in Norway the two first years after planting.We analyzed low molecular weight phenolic compounds by HPLC and condensed tannins by the acid-butanol assay. Sampling year explained most of the variance in phenolic defense, followed by environment (growing location), while the genetic background (provenance) showed the least explanatory power. After the first year in the field, the northernmost growing location had about 70% higher concentration of low molecular weight phenolics than the southern growing locations. The concentrations of condensed tannins, however, were lowest in the north. The mean concentration of total low molecular weight phenolics was twice as high after the first year compared to the second year. After the second year, the differences between the growing locations in many cases disappeared. The differences between the growing locations are probably caused by differences in temperature and soil fertility, while we attribute the decrease in low molecular weight phenols from the first to the second year to decreased water and nutrient stress, as well as aging. Our results suggest that intraspecific variations in concentration and composition of phenolic compounds in beech are caused by differences in the environment to a greater extent than the genetic background, which may indicate fast changes in chemical defense with climate change.

The entomofauna of a veteran beech tree Fagus sylvatica L. in Kemerton civil parish (CP) in Watsonian East Gloucestershire VC33 was studied at widely spaced intervals for 22 years prior to its collapse during 2018. The richness of the entomofauna which demonstrates links with regional Urwald is remarkable given the position of the tree within the curtilage of a settlement and as a support system for Urwaldtier it was probably the best-endowed beech tree in the region. Elements of this fauna have clear affinities both with those of the Bredon Hill escarpment and with the primary river valleys. Key species are discussed and the importance of veteran ash as an agent of biotic continuity is confirmed.

Mycorrhizal fungi play an important role for the nitrogen (N) supply of trees. The influence of different mycorrhizal types on N acquisition in tree–tree interactions is, however, not well understood, particularly with regard to the competition for growth-limiting N. We studied the effect of competition between temperate forest tree species on their inorganic and organic N acquisition in relation to their mycorrhizal type (i.e., arbuscular mycorrhiza or ectomycorrhiza). In a field experiment, we quantified net N uptake capacity from inorganic and organic N sources using 15N/13C stable isotopes for arbuscular mycorrhizal tree species (i.e., Acer pseudoplatanus L., Fraxinus excelsior L., and Prunus avium L.) as well as ectomycorrhizal tree species (i.e., Carpinus betulus L., Fagus sylvatica L., and Tilia platyphyllos Scop.). All species were grown in intra- and interspecific competition (i.e., monoculture or mixture). Our results showed that N sources were not used complementarily depending on a species’ mycorrhizal association, but their uptake rather depended on the competitor, indicating species-specific effects. Generally, ammonium was preferred over glutamine and glutamine over nitrate. In conclusion, our findings suggest that the inorganic and organic N acquisition of the studied temperate tree species is less regulated by mycorrhizal association but rather by the availability of specific N sources in the soil as well as the competitive environment of different tree species.

Through a common garden (provenance) experiment, we investigated the metabolic responses to climatic stress with regard to the acclimation potential of different European beech (Fagus sylvatica L.) populations. Selected enzymatic and non-enzymatic antioxidants were analyzed in leaves. Peroxidase (POD) and polyphenol oxidase (PPO) enzyme activity, total protein content as well as ABTS [2.2’-azino-bis-(3-etylbenzothiazoline)-6-sulphonic acid] antioxidant capacity were measured in the leaves of selected populations. Major leaf polyphenols were identified and their relative amounts were compared. Significant correlations were found between phenotypic (diameter growth) response to simulated climatic stress and the activity (and amount) of selected chemical components. The concentrations of certain polyphenols, POD enzyme activity, and total protein content may be chemical indicators of the acclimation potential of populations and may contribute to the forecasting of climate change effects, which can aid in the selection of suitable propagation material for adaptive silviculture.

Research on mixed forests has mostly focused on tree growth and productivity, or resistance and resilience in changing climate conditions, but only rarely on the effects of tree species mixing on timber quality. In particular, it is still unclear whether the numerous positive effects of mixed forests on productivity and stability come at the expense of timber quality. In this study, we used photographs of sawn boards from 90 European beech (Fagus sylvatica L.) trees of mixed and pure forest stands to analyze internal timber quality through the quality indicator knot surface that was quantitatively assessed using the software Datinf® Measure. We observed a decrease in knot surface with increasing distance from the pith as well as smaller values in the lower log sections. Regarding the influence of neighborhood species identity, we found only minor effects meaning that timber qualities in mixed stands of beech and Norway spruce (Picea abies (L.) H. Karst.) tended to be slightly worse compared to pure beech stands.

The potential utilisation of natural regeneration of European beech (Fagus sylvatica L.) for forest conversion has received little attention to date. Ecological knowledge is necessary to understand and predict successful natural regeneration of beech. The objective of this study was to improve understanding of what drives the occurrence of beech regeneration and, once regeneration is present, what drives its density. In the study, we utilised a forest inventory dataset provided by Sachsenforst, the state forestry service of Saxony, Germany. The dataset was derived from 8725 permanent plots. Zero-altered negative binomial models (ZANB) with spatial random effects were used to analyse factors influencing occurrence and density simultaneously. The results provided by the spatial ZANB models revealed that the probability of the occurrence of beech regeneration is highly dependent on seed availability, i.e. dependent on source trees in close proximity to a plot. The probability of beech regeneration rises with the increasing diameter of a potential seed tree and decreases with increasing distance to the nearest potential seed source. The occurrence of regeneration is affected by overstorey composition and competition exerted by spruce regeneration. Where sites are affected by groundwater or temporary waterlogging, the impact on the occurrence of regeneration is negative. Although distance to the nearest potential seed source has an influence on occurrence, this variable exerts no influence on density. A high regeneration density arises in conjunction with a high beech basal area in the overstorey. Beech regeneration density, but not occurrence, is negatively affected by browsing intensity. These variables can be used to predict the occurrence and density of beech regeneration in space to a high level of precision. The established statistical tool can be used for decision-making when planning forest conversion using natural regeneration.

Outcomes after an abrupt, storm-caused loss of spruce shelterwood (Picea abies L. Karst.) overstories on advanced planted beech (Fagus sylvatica L.) were investigated, including effects of developmental stage and beech stand density on growth after release. Six years after overstorey loss by storm Kyrill in January 2007, heights and root collar diameters were measured, along with annual length of the main shoot and ring widths of the stem and strongest branch. No significant difference in the total height of released and sheltered beeches was found at six years after shelter loss, but annual growth of the main shoot of released beeches increased from the second year after release. Overall growth patterns of released and sheltered beech differed significantly. Diameter growth and that of the strongest branch increased strongly after shelter loss. Height-to-diameter ratio (H/RCD) indicated that sheltered beeches with higher densities were slenderer. However, no differences were found in growth response between young stands and beech in the thicket live stage. Overall, advanced planted beech beneath a spruce shelterwood of medium canopy closure showed vigorous height growth and a qualitatively desired form. Sudden release of the planted beech enhanced diameter growth of stem and branches, which is undesirable for timber quality. Findings suggest that advanced planted beech should not be released by abruptly cutting the shelterwood. Instead, with stepwise canopy opening beech should gradually adapt to the open conditions.

1. Forest regrowth following farmland (agriculture and pasture) abandonment has been positively associated with a number of processes including the regulation of hydrological cycling, the enhancement of soil functioning and an increase in forest productivity and carbon (C) sequestration. Although these changes in eco-system functioning post-farmland abandonment have been observed in multiple locations and studies, the ecophysiological basis underpinning these patterns re-mains unclear. Here, we examine whether increased forest expansion following pastureland abandonment is associated with greater water-use efficiency (WUE) and legacies from previous land use in terms of nitrogen (N) availability., 2. We thus explored differences in leaf traits and N availability between recently es-tablished (post-1950) beech Fagus sylvatica (L.) forests on former pastureland and long-established beech forests (pre-1950). The investigated leaf traits were SLA, leaf N concentration (%N) and intrinsic WUE (iWUE, i.e. the ratio between photo-synthesis and stomatal conductance); as well, leaf and soil stable N isotope compo-sition (δ15N) and total %N were used to assess changes in N availability. Finally, we compared the correlation strength between the above-mentioned parameters and those associated with tree productivity (wood density and basal area increment, BAI) and the richness of ectomycorrhizal fungi (ECM) in these two forest types., 3. Recent forests had greater iWUE than long-established forests, which was associated more with lower SLA than leaf %N. Leaf and soil δ15N were more robust proxies than %N for detecting differences in N availability. Less negative leaf and soil δ15N values in recent versus long-established forests suggest, on the one hand, greater N avail-ability, probably due to higher historical N input originating from animal excreta on these former pasturelands, and, on the other hand, an increase in N loss pathways., 4. Our results point to greater correlations between leaf δ15N, tree iWUE and pro-ductivity in recent forests than in long-established forests, thereby suggesting a close link between C and N cycles. Our findings also highlight different N dynam-ics between the two forest types, with recent forests showing ‘leaky’ N cycling wherever lower N retention by trees and associated ECM fungi occurs as a legacy of previous land use., This study was supported by the projects: SPONFOREST (APCIN_ 2016_0174), NEWFORLAND (RTI2018-099397-B-C22 MCIU/AEI/ERDF, EU) and BEEMED (SGR913 Generalitat de Catalunya). Etal.was supported by the postdoctoral grant Juan de la Cierva-Formación from the Spanish Ministry of Economy, Industry and Competitiveness (grant no. FJCI-2015-26848). T

The relative importance of environmental factors and species pool in natural regeneration processes is still intensively disputed. Is environmental filtering especially important for species with higher requirements for temperature and soil fertility? Is the seed source limitation especially pronounced among tree species with lower dispersal abilities? Trees, seedlings and saplings measurements were conducted in 600 plots of 0.05 ha distributed in a regular grid in the Tatra Mountains (elevation range 817–1797 m a.s.l.). Boosted regression trees were used to analyse the relationships between the numbers of young trees, factors acting as environmental filters and the potential seed source availability. The most important factor affecting the distribution of young trees of most species was elevation; bedrock type was the second most important factor for Acer pseudoplatanus, while potential solar radiation was important for Sorbus aucuparia. The relationship between the presence of mature trees and abundance of young ones was strong in Fagus sylvatica, moderately strong in A. pseudoplatanus, and weak in Picea abies, Abies alba and S. aucuparia. The role of environmental factors in shaping the abundance of young trees varies strongly among species, while the seed source availability is very important for large-seeded trees.

The study defines the hazards for European native trees, such as silver fir and European beech generated by extreme weather events in Poland in 1954–2015. For this purpose, these extremes have been ranked in terms of their frequency. Trends of their frequency over studied period have also been tested. The study was based on meteorological data collected from 6 weather stations situated in central and eastern Poland, in the vicinity of the northeastern edge of the silver fir and European beech ranges. It was found that weather extremes which pose the largest threat to trees in Polish forests were late spring frost and strong winds. On average, these extremes occurred several times a year. Droughts and heavy snowfalls were less frequent and occurred every 1.3–4.7 years, on average. Winter severe frost was the rarest and occurred every 5.1–10.1 years. It should be emphasised that, despite the observed global warming, the weather extremes typical for winter and spring, namely severe frost, late spring frost and heavy snowfalls, were also present in Poland in the twenty-first century and no negative trend in their frequency was identified. However, a negative trend in the De Martonne aridity index was identified at some weather stations, which indicates an increased risk of drought.

As the demand for dried timber has been increasing worldwide, drying of timbers is required to supply the demand in the manufacturing industries of furniture and other interior woodwork. During the drying process, some condensation will occur, resulting in liquids' emission, which requires disposal. in the liquid condensate, there are many substances at low concentrations that make their recovery uneconomic. After revealing the potential of the substances available in these condensates, biotechnological processes can be employed to produce high value-added products. This condensate contains tree sap, including proteins, enzymes, and many natural compounds such as terpenoids, alkaloids, phenolic compounds. Thus, it is considered that these natural compounds might be beneficial in pharmaceutical applications. Natural compounds such as phenolic compounds are bioactive substances that have antioxidant, antimicrobial, and cytotoxic activities. This study was aimed to characterize the condensate from the Rf-vacuum drying process of beech (Fagus sylvatica L.), walnut (Juglans regia L.), and restharrow (Onosis arvensis L.) in terms of antioxidant capacity, total phenol content, antimicrobial activity, and cytotoxicity. Obtained data revealed that condensates from the Rf-vacuum drying process inhibited the growth of both S. epidermidis and E. coli significantly.

Recently, many studies worldwide tapped tree ring pattern for detection of growth events and trends caused by weather extremes and climate change. As long-term experiments with permanent survey of all trees are rare, growth trend analyses are mostly based on retrospective measurements of growth via increment coring or stem analyses of the remaining individual trees in older forest stands. However, the growth of the survivor trees in older stands may only unsufficiently represent the course of growth of the dominant trees throughout the stand development. Here, the more than 100 years survey data of the European beech (Fagus sylvatica L.) thinning experiment Fabrikschleichach in South Germany are used to show the long-term changes in social ranking of trees and their consequences for growth trend detection by retrospective tree ring analyses, for stand dynamics and silvicultural management. Firstly, a significant social upwards drift of initially medium-sized trees till 2010 is shown based on the trees' percentiles in the stem diameter distribution in 1904 versus 2010. The social climbing is stronger on the thinned compared to the unthinned plots. Secondly, we show that 40–60% of the 100 tallest trees in 1904 were replaced by social climbers and down-ranked below the 100 tallest trees till 2010. Linear mixed model analyses reveal that the long-term trend of the diameter growth of the 100 dominant survivors in 2010 was on average by 23% steeper than the trend of the 100 tallest starters in 1904. This indicates that the survivors had a steeper and longer lasting growth than the originally dominant trees. Thirdly, the diameter growth trend in the last 20 years, from 1990 to 2010, is analyzed in dependency on the current and past social position. A linear model shows that early subdominance or suppression can significantly steepen the growth trend a century later and vice versa.Finally, we discuss the implications of the social drift for the survivor-based growth trend analyses, for the stand dynamics, and silvicultural management.

In the last few decades, the use of environmental radionuclides, particularly caesium-137 (137Cs), represented one of the most valid methods for estimating soil erosion. However, the cost associated with the use of the equipment needed for radiometric analyses is still high and, for this reason, finding more easily measurable indicators can be useful. There is a strong correlation between 137Cs, organic carbon (OC), nitrogen (N) and water soluble phenols (WSP) exists, indicating the latter parameters as possible early indicators of soil erosion. Based on the above assumptions, the main purpose of this work is to identify specific soil chemical parameters able to indicate early triggering of soil erosion. Specifically, several soil parameters such as pH, electric conductivity (EC), WSP, OC, N and C/N have been evaluated against 137Cs and on a comparative basis. In addition, since the rate of soil erosion depends on the degree of coverage and canopy structure, two different tree species (Pinus nigra laricio Poir. and Fagus sylvatica L.) have been considered in this contribution in which ten different scenarios of forest management have been analysed. The results show that the reduction in tree cover of managed sites triggers erosion and nutrient loss processes. It has been observed that the loss of 137Cs, compared to the control areas, is closely correlated with those of WSP, OC and N. These parameters (WSP, OC and N), more easily assessable, can be a valid tool to understand easily, triggering of erosive phenomena.