Oak-hornbeam Forests Research Articles

The edificator role of hazel in the formation of the Collembola taxocene of subcontinental oak-hornbeam forests of the Wigerski National Park (Poland)

A comparative analysis of the taxonomic and ecological structure of collembolan taxocenes in the subcontinental oak-hornbeam forests of Viger National Park with different projective coverage of hazel was carried out. It was established that the fauna of the collembola of the studied forests of the Viger National Park is represented by 51 species of collembola belonging to 31 genera and 11 families. The fewest species were registered in the areas without hazel, and the most - with its participation. The obtained data indicate that the absence or insignificant presence of hazel leads to a decrease in the species richness of the Collembola taxocene. On the other hand, the presence of hazel in the experimental plots of the oak-hornbeam forest allows more species of collembolans to survive both at the level of point and coenotic alpha-diversity. This may indicate that in the studied forest communities with a significant presence of hazel, the capacity of the environment for Collembola increases compared to those where hazel is absent or represented by a small number of tree shrubs. Folsomia quadrioculata, Isotomiella minor, Lepidocyrtus lignorum, as well as polytopic forest species: Pogonognatellus flavescens and Pseudosinella horaki. Species with the highest frequency of occurrence both in the soil samples and in all studied areas of the oak-hornbeam forest were also such eurytopic species as Parisotoma notabilis, Pogonognathellus flavescens, Lepidocyrtus lignorum, Pseudosinella horaki. Among the polytopic forest collembola, eight species can be classified as saproxylic. Three of them, i.e. Proisotoma minima, Vertagopus cinereus, Pratanurida boerneri, are saproxylobionts. Species such as Pseudachorutes parvulus, Neanura muscorum, Neanura minuta, Oligaphorura absoloni and Entomobrya corticalis are saproxylophiles, i.e. species that prefer dead wood but also live in other forest microhabitats. Also, 35 species are typical litter or soil inhabitants. Therefore, the research results indicate the important importance of hazel in the formation of the ecological structure of collembolan taxocenes in the oak-hornbeam forests of the studied region. However, the detected changes in the investigated taxocenes are insignificant and mainly concern indicators of cadastral species richness according to P. Whittaker, as well as the numerical ratio of species.

A contribution to the spider fauna of the Dnister Canyon NNP and its environs

The research on the spider fauna of the Dnister Canyon National Nature Park, which is located on the territory of the Chortkiv district of the Ternopil oblast (Ukraine), is presented. The study area lies within the deciduous forest zone in the region of Roztochia-Opillian hill ridges and the West Podolian upland region. The history of the study of the spider fauna in the region is analyzed, including the one related to the works of famous naturalists of the 19th century: A. Wierzejski, M. Łomnicki, L. Wajgiel, M. Nowicki, and L. Koch. It was established that most of the clusters of the National Nature Park were not covered by the research, and its faunal list includes only about 85 spider species, and even then, a significant part of them was collected on the outskirts of the protected area. During the several-day expeditions in 2000 and 2016, 93 species belonging to 20 families were found. The species-rich families were Linyphiidae (15 species; 16.1% of species diversity), Araneidae (12 species; 12.9%), Lycosidae, Theridiidae, and Thomisidae (11 species each; 11.8%). Information on the distribution in the world and in Ukraine of two rare and little-known species of spiders, namely Tegenaria campestris (C. L. Koch, 1834) and Harpactea saeva (Herman, 1879), which were found in a rotten log in an oak-hornbeam forest, is given. Taking into account the literature-derided data, the fauna of the park currently includes 135 spider species from 21 families. During the research, 42 species of spiders were not confirmed. First of all, this is due to the very short period of expeditions and the lack of stationary study plots, and therefore of materials from pitfall traps or seasonal from spring to autumn collections. In particular, no tarantula (Lycosa singoriensis) was found. This species was typical and widespread in Podolia at the end of the 19th century, however, according to a survey of local residents, it is now very rare, and its records on the territory of the National nature park need confirmation. To supplement the fauna and understand the features of its formation in the region, further comprehensive research of zonal forests and steppe areas on the slopes of river canyons is necessary.

Classification of European oak–hornbeam forests and related vegetation types

AbstractAimsOak–hornbeam forests and related vegetation types (phytosociological order Carpinetalia betuli) are widespread in temperate western Eurasia. However, their national classification systems are poorly compatible, and a broad‐scale classification based on numerical analyses is lacking. Therefore, we aimed to establish a unified formalized classification system based on a large data set of vegetation plots covering the entire range of these forests.LocationEurope, Anatolia, Caucasus and northern Iran.MethodsWe compiled a data set of 15,817 vegetation plots from the European Vegetation Archive and the Hyrcanian Forest Vegetation Database, using the formal definition of the EUNIS habitat type T1E Carpinus and Quercus mesic deciduous forest. We classified the data set using TWINSPAN. Biogeographically and ecologically similar plot clusters were merged into oak–hornbeam forest types, which were interpreted as alliances. We also developed expert systems for automatically classifying vegetation at the alliance level for both the EuroVegChecklist (EVC) system and the revised classification. In addition, we calculated ordinations to show the major gradients in the species composition of the data set.ResultsWe present a revised classification system of the order Carpinetalia betuli with nine alliances, including basic descriptions of their species composition, distribution, ecology and syntaxonomy. The analyses largely supported the biogeographic concept of classification, analogous to EVC. Compared to EVC, we recognized an additional alliance Physospermo verticillati‐Quercion cerridis (southern Italy) but found no support for the alliances Astrantio‐Carpinion, Erythronio‐Carpinion and Scillo‐Quercion. The greatest difference in species composition was found between the southern and northern‐northeastern Carpinetalia types. Expert systems for the revised classification system (~89% of plots classified) and the EVC system (~72%) are also included.ConclusionsWe provide the first comprehensive overview of alliances of the order Carpinetalia betuli across its whole distribution range. The associated expert systems allow consistent application of the classification of these forests in nature conservation, habitat monitoring, and biodiversity and ecological research.

Small-Scale Environmental Heterogeneity Enhances Tree Recruitment through Carbon Recharge and Water Use Diversification

Studying regeneration processes in oak-dominated forests requires a multi-faceted approach that considers local factors, disturbances, management actions, and tree responses. Our aims were to quantify the carbon and water-use responses of saplings and evaluate ecological consequences at the early tree regeneration phase of a pedunculate oak-hornbeam forest. We measured plant eco-physiological parameters using an open-chamber IRGA equipment in large experimental canopy gaps (instantaneous field data) and greenhouse (climate-controlled reference data) conditions. We used the non-parametric Kruskal–Wallis ANOVA test to analyze differences and similarities in the gas-exchange response. Functional fingerprints indicated shared resource use and efficiency functions at species-specific performance levels with temporal variations. Medium-level and seasonally balanced carbon uptake and water-use functions characterized pedunculate oak (Quercus robur L.) and European hornbeam (Carpinus betulus L.). In contrast, the response patterns in wild cherry (Prunus avium (L.) L.) and green ash (Fraxinus pennsylvanica Marshall) were dominated by water use. Goat willow (Salix caprea L.) had consistently elevated gas-exchange levels with the largest seasonal variation among the study species. We found that trees could be ranked on a relative isohydric-to-anisohydric scale regarding their species–environment interaction. According to the carbon-gain response pattern coupling with a non-structural carbohydrate exchange scheme, we were able to classify tree species as having medium- and long-term carbon resource management. In conclusion, spatially heterogeneous and temporally balanced canopy gaps facilitate tree species’ development and mixed-stand regeneration by providing a functionally diversifying recruiting environment.

Seasonal variation of size-resolved aerosol fluxes in a Peri-urban deciduous broadleaved forest

Eddy covariance measurements of aerosol fluxes were performed above an oak-hornbeam forest in the Po Plain (Northern Italy), from February to May and from September to December 2019. Measurements aimed at assessing the influence of forest phenology and leaf presence/absence on the seasonal evolution of size-segregated aerosol fluxes. The size-resolved aerosol concentration in the range 0.006-10 μm was sampled with a 14-stage impactor (ELPI+, Dekati, FI), and the filters exposed in May were subjected to chemical analysis. Over the whole sampling period, the forest removed from the atmosphere an average of 3.12 mg of aerosol m−2 d−1. The direction and the intensity of the aerosol fluxes were not constant through the year, as a strong seasonal and size-dependent variability emerged. In particular, leaf-presence drove a net deposition of the accumulation mode aerosol (100 nm< particle diameter Dp<1000 nm) and an emission of the Aitken (10 nm< Dp<100 nm) and coarse mode (Dp>1000 nm) aerosols. On the contrary, in absence of leaves all the sub-micrometer aerosol size-classes showed net daily upward fluxes, while coarse mode aerosol fluxes were prevalently downward. Monthly averages of deposition velocities of Aitken and accumulation mode aerosols correlated with the Leaf Area Index (LAI) seasonal trend, thus indicating an important role of the amount of the leaf surface area on the deposition and emission of these size-classes. Furthermore, an influence of the stomatic activity was suggested for the Aitken mode aerosol, since its deposition velocity followed the same diel course of the stomatal conductance to water. The analysis of the influence of meteorological parameters on aerosol deposition velocities highlighted that dynamic and convective turbulence (described by friction velocity, u* and Deardorff velocity, w*) enhanced the vertical aerosol exchanges, both upward and downward, while the approaching of condensing conditions reduced the flux intensities.

Forest ecosystems’ vulnerability of Emerald site “Pădurea Hîncești” to climate change

The Emerald site “Pădurea Hîncești” is located in central part of the Republic of Moldova territory and contains forest ecosystems dominated by oak species (the most valuable species of the national forest fund). Scientific research on the assessment of the protected forest ecosystems vulnerability, under the impact of climate change, using ecoclimate indices (De Martonne Aridity Index – IM; Conventional Humidity Balance – K; and Ellenberg Quotient - EQ) and mapping of obtained results, are very current and important in forest sustainable development. The study determined that, per general, Emerald site has climatic conditions favorable for growth and development of forest ecosystems on the entire surface (the K index values being above unit, for the period when the air temperature was ≥ 10°C). IM values calculated for the Emerald site (19912020) range from 24.2 to 37.0 units, framed territories from semi-arid climatic conditions, to humid climatic conditions, favorable for the development of steppe and forest communities. In Emerald site, there are two areas of forest vulnerability to climate aridity: high vulnerability level, within moderately arid climate and lasting disturbances of the moisture; and medium vulnerability level, within slightly humid climate and disturbances of the moisture in some years. Based on the IM temporal trends, there is future risk to pass from a medium to a high forest vulnerability to climate change in almost all site. The EQ values vary between 29.5 and 46.0 units (developing climate conditions favorable for oak-hornbeam forests development growth in the northern side of site; for oak forests - in the central part, and for dry / arid oak forests -in the southern part). Concerns about the sustainable management of the forest sector and the expansion of forest areas with tree species adapted to new environmental conditions must be a constant in the country's sectoral priorities.

Presence of alien Prunus serotina and Impatiens parviflora in lowland forest fragments in NE Slovenia

Temperate alluvial, riparian and lowland forests are the European forests with the greatest presence of invasive alien plants. Consequently, identifying the environmental conditions for and other drivers behind the establishment of invasive species in natural forest communities is crucial for understanding the invasibility of these habitats. We focused on fragments (patches) of Illyrian oak-hornbeam forest in NE Slovenia, which are the least studied in this regard. Because alien phanerophytes and therophytes are significantly over-represented compared to native plants in lowland forests, we selected two representative invasives: the phanerophyte Prunus serotina and the therophyte Impatiens parviflora. By using logistic regression models on vegetation surveys, environmental data based on Ellenberg´s indicator values, and patch metrics, we identified patch characteristics explaining the presence of each species. Moreover, we included human impact in the models. We reveal significant characteristics differentiating P. serotina from I. parviflora. We also show that the perimeter-area ratio and soil nutrients of the forest patches correlate significantly with the presence of P. serotina, while human disturbance correlates significantly with the presence of I. parviflora. Our results and a similar approach for other invasive plant species can be applied to assess habitat invasibility on potential and species’ current geographic distribution, as well as to develop management plans.

Synthesis of palaeoecological data from the Polish Lowlands suggests heterogeneous patterns of old-growth forest loss after the Migration Period

Human impact on Central European forests dates back thousands of years. In this study we reanalyzed 36 published pollen data sets with robust chronologies from Polish Lowlands to determine the patterns of large-scale forest decline after the Migration Period (fourth to sixth century CE). The study revealed substantial heterogeneity in the old-growth forest decline patterns. Using new high-resolution studies, we could better understand the timing of this transition related to increasing economic development. After the Migration Period, forest expansion continued until the seventh to ninth centuries cal. CE, when the dawn of Slavic culture resulted in large-scale forest decline, especially in north-western and north-central Poland. Later, forest decline was recorded mainly in north-eastern Poland and was related to Prussian settlements, including activities associated with the Teutonic Order, as well as with new settlements from the fourteenth century. The composite picture shows a varied spatio-temporal forest loss and transition towards the present-day, human activity dominated landscapes. However, some sites, such as in north-eastern Poland, are characterized by a less abrupt critical transition. The pristine nature of the oak-hornbeam forest had already been destroyed in Early Medieval times (eighth to ninth centuries cal. CE) and the potential for recovery was largely lost. Our study has confirmed previous assumptions that the decline of hornbeam across the Polish Lowlands may be an early indicator of local settlement processes, preceding severe forest loss, and establishment of permanent agriculture.

Settling in: space utilization behaviour of translocated Hazel Dormice (Muscardinus avellanarius)

The Hazel Dormouse (Muscardinus avellanarius) is protected under the EU’s Habitat Directive and its national implementation, whereby physical harm to individuals as well as the destruction of breeding and nesting sites is prohibited. Within the context of inevitable environmental impacts these protection goals are not always maintained. Therefore, mitigation and compensation measures to secure a population’s viability are required. For sedentary and less mobile species like the Hazel Dormouse, mitigation often includes the translocation of individuals to a different habitat patch. In 2017 and 2018 a total of 108 individuals were translocated from an old growth oak-hornbeam forest to an area that was re-forested 40 years ago. Prior to translocation, individuals were equipped with a radio transmitter and they were followed for three consecutive nights and one control night, during which bearings were taken every five minutes using the triangulation technique. A control group of established Hazel Dormice was followed in the same manner. Nests and resting sites were searched for during the daytime. Twelve male Hazel Dormice were radio-collared and between 234 and 427 bearings were taken per individual. Resting sites of translocated dormice were mainly located within the forest canopy (33.3%). Furthermore, individuals were often found active during the daytime. Mean activity range size (MCP) and resource search areas (LoCoH 95 %) were larger in translocated dormice, whereas the mean core habitat size (LoCoH 50 %) was larger in established dormice. The activity range during all of the monitored nights overlapped significantly more in established dormice, demonstrating exploratory behaviour by translocated individuals.

The afterlife of herbaceous plant species: A litter decomposition experiment in a temperate oak-hornbeam forest

Understanding the mechanisms of singular species and their traits impacts on ecosystem functions, is crucial in the era of unprecedented anthropogenic changes of the environment, e.g. to predict changes in carbon and nutrient cycling connected with species shifts. It may allow us to take protective measurements and mitigate the negative effects of global changes. Litter decomposition is a crucial process shaping nutrient cycling in ecosystems. Studies on decomposition in forest ecosystems are mainly limited to foliar litter. In contrast to woody plant species, our knowledge of decomposition of herbaceous plants is scarce. Thus, unanswered questions remain about the model that best describes the decomposition process of herbaceous plants. The relationship of decomposition rate to functional traits is unknown for this species pool. We used the litter bag method to determine the decomposition rate of 13 herbaceous plant species and four overstory tree species growing in a temperate oak-hornbeam forest. We showed that the litter decomposition rate and C and N release were higher in spring ephemerals than summer green herbaceous species, as the plants with small total individual aboveground biomass (TAB) and small total leaf area (TLA) decomposed the fastest. Our results demonstrate that in this generally acquisitive group of plants, size traits have a stronger impact on decomposition than economic traits. For almost all species, the two-phase exponential decay model explains the course of herbaceous species litter decomposition only slightly better than the single exponential model.

An introduced pine shapes gastropod assemblages in the Central European broadleaved forest

The aim of this study was to determine the impact of the introduction of Pinus sylvestris on the mesofauna of the forest floor in the Central European oak-hornbeam forest, using gastropods as a model group. Data on terrestrial gastropods and environmental variables were collected in 2012–2014 from 25 study plots (14 without pine and 11 with pine) at 14 localities scattered across Wielkopolska province in mid-western Poland. Forty-two species (34 of snails and 8 of slugs) were recorded, with significantly lower numbers of individuals and species in plots with pine. The negative effect of the presence of pine trees was most evident at the level of gastropod abundance. The species composition of gastropod assemblage was also significantly different between plots with and without pine. The symptoms of the assemblage’s reduction, impoverishment and trivialization thus suggested a long-term effect of the introduced pine on natural mesofauna. However, gastropod assemblage was shaped not by one dominating factor, but by a multifactorial combination of interacting variables, particularly related to herbaceous vegetation and to the tree- and shrub layer. Herb layer cover, moisture (reflected in the herbs), fertility (reflected in the herbs), and locally also the amount of calcium in the soil and insolation were found to be significant for the structure of gastropod assemblages. More environmental variables were significant at the sample level (i.e. within forest) than at the plot level (i.e. between forests), which is likely to be due to greater variation in the conditions within a rich forest as opposed to lower variation between forests. This highlighted the importance of using a two-scale approach to understand the conditions affecting gastropod assemblage structure in a habitat that is seemingly homogenous on the macro scale, but diversified and mosaic in the micro scale. The negative effects of pine introduction and the positive significance of the multifactorial combination of habitat factors at the macro- and micro level appear as important guidelines for favourable biodiversity management in the Central European oak-hornbeam forest and in other broadleaved forests.

PLANT COVER OF THE LOCAL LANDSCAPE RESERVE «HARIACHYI URBAN» (CHERNIVTSI CITY)

The results of the studies of forest communities on the local landscape reserve «Hariachyi Urban» (Chernivtsi city) are presented. It was established that forest vegetation divided into 2 alliances, and 2 orders of the class Carpino-Fagetea sylvaticae Jakucs ex Passarge 1968. These communities represent 2 habitat types from the Annex I of the Habitats Directive: 9130 Asperulo-Fagetum beech forests and 9170 Galio-Carpinetum oak-hornbeam forests, and 2 biotope types from the Resolution 4 of the Bern Convention: G1.6: Beech forests (Fagus woodland) and G1.A1 Quer-cus – Fraxinus – Carpinus betulus woodland on eutrophic and mesotrophic soils, respectively. Also, coenoses men-tioned in the «Green Book of Ukraine» (2009), e.i. common oak forests (Querceta roboris) with common ivy (Hedera helix) domination, are presented here. So, it confirms an important role of this local reserve for biodiversity conserva-tion. According to the literature and herbaria (CHER) data, since the 2nd half of the 19th century, 18 rare plant species listed in the «Red Data Book of Ukraine» (2009) were noticed for this area. For 13 species, the current localities have not been confirmed. Among them, 8 species were associated with grassland, that have not been preserved here, and 5 species were sylvatic. During the last 50 years, 5 plants species from the «Red Data Book of Ukraine» (2009) have been found on the studied area, and only 3 species were confirmed in this study. In studied plant communities, 8 alien plant species were noticed, which indicate the increasing of adventitization rate. Therefore, changes in forest plant communities can be traced in direction of the disappearance of rare plant spe-cies caused by the destruction of landscapes, fragmentation and degradation of preserved natural biotopes, and in-tensification of recreational activity. In addition, increasing of the synanthropization rate and expansion of alien plant species, including species with a high invasive potential, are observed. The initiated inventory studies of the floristic and coenotic diversity in the local reserve will serve as the basis for organizing its phytodiversity state moni-toring.

Whole genome duplication increases ecological niche breadth of the perennial herb Urtica dioica

Environmental niche modelling and associated species distribution models often ignore intraspecific ecological differentiation linked with ploidal differentiation, i.e. the occurrence of several cytotypes of the same species. Here we tested the hypotheses that (i) the tetraploid (4x) cytotype is characterized by a broader ecological niche than the diploid (2x), and (ii) niche differentiation at the regional scale can serve as a proxy measure for differentiation at a smaller landscape scale in Urtica dioica, a perennial herbaceous plant with two prevailing cytotypes (2x and 4x). We focused on southern Moravia (Czech Republic), an area with a high diversity of vegetation types and the occurrence of both diploid and tetraploid cytotypes of U. dioica. To explore the geographical distribution, ecological preferences and habitat affinities of the diploid and tetraploid plants, we collected individuals at two different spatial scales: regional (~1200 km2) and landscape (9.1 km2). We used flow cytometry to determine the ploidy level of all the plants collected and determined the distribution of the different cytotypes both in geographical and ecological space. We also compared the habitat affinities of the diploid and tetraploid plants. Analyses of ploidy revealed 93 diploids and 325 tetraploids (regional scale: 42 diploids, 85 tetraploids; landscape scale: 51 diploids and 240 tetraploids). Diploid plants occurred only in the wetter parts of the landscape and this pattern was very similar at both scales. In contrast, tetraploids occurred along the whole moisture gradient at both scales. Diploids and tetraploids differed also in their habitat affinities. While diploids occurred relatively more frequently in alluvial and wet forests, managed broadleaved forests, alluvial and wet meadows, and wetlands and riverbanks, tetraploids preferred oak and oak-hornbeam forests, ravine forests, actively managed meadows, human settlements and vineyards. Our data clearly show an ecological niche differentiation between diploid and tetraploid cytotypes of Urtica dioica. While tetraploids have a broad ecological tolerance and consequently a wide geographical distribution, diploids occur only in a narrow range of ecological conditions and their distribution is restricted to areas with a shallow water table in the bottoms of valleys. Thus, ploidal differentiation, confirmed for many plant species, should be included in environmental niche modelling and species distribution models.

Ecological assessment of dead woodvolume in hornbeam-oak forest in «Medobory» Nature Reserve

The volume of coarse woody detritus in the 139year-old hornbeam-oak forest stand of natural origin on the territory of the «Medobory» Nature Reserve have been studied. The study of dead wood was carried out on a sample plot (0.24 ha) by the method of continuous accounting. It was found that the volume of woody detritus in the forest ecosystem is 108.8 m3∙ha–1 and consists of fallen (32.1%) and standing (67.9%) deadwood. The main part of the dead wood volume is formed by two tree species — common oak (Quercus robur L.) (49.1%) and wychelm (Ulmus glabra Huds.) (48.4%). In general, woody detritus is characterized by I–V classes of decomposition, while detritus of decomposition stage II prevails (40.9%), shares of other stages are slightly smaller: I (27.8%), III (18.6%) and IV (11. 1%). The share of detritus of the last (V) decomposition stage is insignificant (1.6%). The volume of standing dead wood is 73.9 m3∙ha–1 and is formed by whole and broken dead trees. In terms of tree species composition, common oak has a significant advantage (65.4%), wychelm has a much smaller share (33.7%), and the share of hornbeam (Carpinus betulus L.) and small-leaved linden is insignificant (Tilia cordata Mill) (less than 1.0%). In the total standing dead wood volume, wood of decomposition stage IIsignificantly predominates (43.6 m3∙ha–1, 59.0%), compared with stage I (30.3 m3∙ha–1, 41.0%). Volume of fallen dead wood is 35.0 m3∙ha–1 and is formed by whole fallen trees, fragments of felled trees (trunks) and rough branches. In terms of species composition, woody detritus of which elm predominates (27.8 m3∙ha–1, 79.7%), much less common oak wood (5.1 m3∙ha–1, 14.6%) and common hornbeam (2.0 m∙ha–1, 5.7%). Fallen dead wood is represented by four stages of decomposition (II–V). In terms of volume, decomposition stage III has an absolute advantage (20.2 m3∙ha–1, 57.9%), detritus of stage II is much less (12.1 m3∙ha–1, 34.7%), and the shares of other stages are insignificant. The predominance of standing dead wood in the total dead wood volume, as well as the dominance of detritus of I and II decomposition stages due to the relatively short period of strict regime of nature conservation, during which the forest ecosystem developed without human intervention, and the impact of forestry activities (selective sanitary cuttings and fallen dead wood removal) in the past.

Resilience of spider communities affected by a range of silvicultural treatments in a temperate deciduous forest stand

To secure the ecosystem services forests provide, it is important to understand how different management practices impact various components of these ecosystems. We aimed to uncover how silvicultural treatments affected the ground-dwelling spider communities during the first five years of a forest ecological experiment. In an oak-hornbeam forest stand, five treatments, belonging to clear-cutting, shelterwood and continuous cover forestry systems, were implemented using randomised complete block design. Spiders were sampled by pitfall traps, and detailed vegetation, soil and microclimate data were collected throughout the experiment. In the treatment plots spider abundance and species richness increased marginally. Species composition changes were more pronounced and treatment specific, initially diverging from the control plots, but becoming more similar again by the fifth year. These changes were correlated mostly to treatment-related light intensity and humidity gradients. The patchy implementation of the treatments induced modest increase in both gamma and beta diversity of spiders in the stand. Overall, spiders gave a prompt and species specific response to treatments that was by the fifth year showing signs of relatively quick recovery to pre-treatment state. At the present fine scale of implementation the magnitude of changes was not different among forestry treatments, irrespective of their severity.

Thinning Response and Potential Basal Area—A Case Study in a Mixed Sub-Humid Low-Elevation Oak-Hornbeam Forest

Competition for resources (light, water, nutrients, etc.) limits the size and abundance of live trees a site can support. This carrying capacity determines the potential carbon sequestration in live trees and the maximum growing stock. Lower stocking through thinning can change growth and mortality. We were interested in the relations between stand structure, increment, and mortality using a long-unmanaged oak-hornbeam forest near Vienna, Austria, as a case study. We expected lower increment for heavily thinned compared to unmanaged stands. We tested the thinning response using three permanent growth plots, in which two were thinned (50% and 70% basal area removed) and one remained unmanaged. We calculated stand structure (basal area, stem density, diameter distribution) and increment and mortality of single trees. Over ten years, the heavily thinned stand had a similar increment as that of the moderately thinned and unthinned stands. The basal area of the unthinned stand remained constant and stem density decreased due to competition-related mortality. The studied oak-hornbeam stands responded well even to late and heavy thinning, suggesting a broad “plateau” of stocking and increment for these forest types. Lower stem density for thinned stands led to a much larger tree increment of single trees, compared to the unthinned reference. The findings of this study need verification for other soil and climatic conditions.

Unequivocal Differences in Predation Pressure on Large Carabid Beetles between Forestry Treatments

Carabid beetles (Coleoptera: Carabidae) are considered as one of the most cardinal invertebrate predatory groups in many ecosystems, including forests. Previous studies revealed that the predation pressure provided by carabids significantly regulates the ecological network of invertebrates. Nevertheless, there is no direct estimation of the predation risk on carabids, which can be an important proxy for the phenomenon called ecological trap. In our study, we aimed to explore the predation pressure on carabids using 3D-printed decoys installed in two types of forestry treatments, preparation cuts and clear cuts, and control plots in a Hungarian oak–hornbeam forest. We estimated the seasonal, diurnal and treatment-specific aspects of the predation pressure on carabids. Our results reveal a significantly higher predation risk on carabids in both forestry treatments than in the control. Moreover, it was also higher in the nighttime than daytime. Contrarily, no effects of season and microhabitat features were found. Based on these clues we assume that habitats modified by forestry practices may act as an ecological trap for carabids. Our findings contribute to a better understanding of how ecological interactions between species may change in a modified forest environment.

The Strong Position of Silver Fir (Abies alba Mill.) in Fertile Variants of Beech and Oak-Hornbeam Forests in the Light of Studies Conducted in the Sudetes

Silver fir is one of the longest living and tallest trees in Europe, it has major commercial importance and may be found in various communities predominantly connected with lower mountainous locations in Central Europe. One of the northernmost ranges in the region is the Sudetes. Currently, the once numerous fir is greatly dispersed, with just several specimens to be found together at one site on average. This drastic reduction in the number of specimens is mainly attributable to intensive forest management, based on the artificial cultivation of fir, conducted in the 19th and 20th centuries, and high industrial air pollution (mainly in the 20th c.). Because practically no firs have been cultivated for the last 200 years, the remaining sites of the species that are remnants of its bigger populations should be regarded as natural. This paper compares fir locations with areas of potential natural vegetation. The obtained results indicate that firs may grow in various types of habitats, with the preferred one being fertile beech woods and richer variants of oak-hornbeam forests. In our opinion, the presented findings are of great importance for the knowledge of the ecology of the species in question and for providing appropriate forest management.

Herbaceous Layer Net Primary Production of Oak-Hornbeam Forest: Comparing Six Methods of Assessment Based on the Seasonal Dynamics of Biomass Increments

Proper estimation of the herb layer annual net primary production (ANPP) can help to appreciate the role of this layer in carbon assimilation and nutrient cycling. Simple methods of ANPP estimation often understate its value. More accurate methods take into account biomass increments of individual species but are more laborious. We conducted our study in an oak-hornbeam forest (site area 12 ha) dominated by beech in NW Poland during two growing seasons (2010 and 2011). We collected herb layer biomass from 7 to 10 square frames (0.6 × 0.6 m). We collected plant biomass every week in April and May and every two weeks for the rest of the growing season. We compared six methods of calculating ANPP. The highest current-year standing biomass (1st method of ANPP calculation) was obtained on May 15, 2010—37.8 g m−2 and May 7, 2011—41.0 g m−2. The highest values of ANPP were obtained by the 6th method based on the sum of the highest products of shoot biomass and density for individual species: 74.3 g m−2 year−1 in 2010 and 94.0 g m−2 year−1 in 2011. The spring ephemeral Anemone nemorosa had the highest share of ANPP with 50% of the total ANPP. Two summer-greens, Galeobdolon luteum and Galium odoratum, each had a ca. 10% share of ANPP. The best results of ANPP calculation resulted from laborious tracking of dynamics of biomass and density of individual shoots.

Characteristics Of Natural Oak Forests Of In Se "Khmilnytske Lisove Hospodarstvo" And Implementation Of Measures For Their Regeneration

As a consequence of the intensive economic use of oak forests in the region, the share of stands of natural origin is significantly reduced, which requires an in-depth study of their condition, productivity, and natural restoration processes. The purpose of this study is to investigate the state, structure, and reforestation processes of oak forests for their further natural reproduction. Generally accepted methods in forestry and comparative ecology were used to compare the dynamics and condition of the studied stands with the reference ones. The paper presents the findings of the study of the productivity and state of natural forests within the state enterprise “Khmilnytske lisove hospodarstvo”. It was found out that natural oak stands are represented by 7 forest types, mainly in fresh hornbeam oak forest (area – 471 hectares). According to the results obtained, it was found that natural oak stands of vegetative origin predominate within the studied enterprise (528.6 ha). They are mainly represented by forests of the 11th age class (188.0 ha). High-bonitat oak forests of the 1st quality class predominate. Mature and over-mature stands have slightly lower productivity (2nd quality class, stand density of 0.6-0.7). The largest total reserve is characterised by stands of the 11th age class. The maximum average reserves are typical for stands of the 9th age class (290 m3 /ha). The greatest share of oak in stand composition (9-10 units) was found in stands of 9-10 age classes. The study shows that the natural renewal of oak is concentrated mainly in fresh sudubrava (fresh hornbeam sudubrava) in plantings in the presence of Scots pine and common oak. The density of natural renewal is 1-3 thousand units/ha. The practical value of the study is conditioned by the possibility of introducing the basic principles of forestry aimed at growing stable high-yield stands of common oak through more complete utilisation of natural renewal