Central European Species Research Articles

Below‐ and aboveground traits explain local abundance, and regional, continental and global occurrence frequencies of grassland plants

Plants vary widely in how common or rare they are, but whether commonness of species is associated with functional traits is still debated. This might partly be because commonness can be measured at different spatial scales, and because most studies focus solely on aboveground functional traits.We measured five root traits and seed mass on 241 central European grassland species, and extracted their specific leaf area, height, mycorrhizal status and bud‐bank size from databases. Then we tested if trait values are associated with commonness at seven spatial scales, ranging from abundance in 16‐m2grassland plots, via regional and European‐wide occurrence frequencies, to worldwide naturalization success.At every spatial scale, commonness was associated with at least three traits. The traits explained the greatest proportions of variance for abundance in grassland plots (42%) and naturalization success (41%) and the least for occurrence frequencies in Europe and the Mediterranean (2%). Low root tissue density characterized common species at every scale, whereas other traits showed directional changes depending on the scale. We also found that many of the effects had significant non‐linear effects, in most cases with the highest commonness‐metric value at intermediate trait values. Across scales, belowground traits explained overall more variance in species commonness (19.4%) than aboveground traits (12.6%).The changes we found in the relationships between traits and commonness, when going from one spatial scale to another, could at least partly explain the maintenance of trait variation in nature. Most importantly, our study shows that within grasslands, belowground traits are at least as important as aboveground traits for species commonness. Therefore, belowground traits should be more frequently considered in studies on plant functional ecology.

Higher susceptibility of beech to drought in comparison to oak

The expected increase in drought severity and frequency as a result of anthropogenic climate change leads to concerns about the ability of native tree species to cope with these changes. To determine the susceptibility of Fagus sylvatica (European beech) and Quercus robur (pedunculate oak) – the two dominant deciduous tree species in Central Europe – to drought, we quantified the climate sensitivity and drought-response of radial growth for both species using an array of dendroecological methods. Tree-ring data were collected from a site east of Coburg, Bavaria which had shown pronounced stress-symptoms (early leaf coloration) during the record drought of 2018. Climate-growth relationships were used to establish the sensitivity of radial growth to multiple climatic variables. The impact of specific drought events on tree growth was quantified using tolerance indices. In addition, we employed a Principal Component Gradient Analysis (PCGA) and remote sensing data (MODIS Normalized Difference Vegetation Index (NDVI)) to delineate the species specific drought responses. Using these methods we were able to show a clear difference in drought susceptibility between beech and oak. Beech displayed a higher sensitivity to temperature and the standardized precipitation evapotranspiration index (SPEI) and showed lower resistance and resilience to drought events than oak. In particular, beech was unable to fully recover from the 2003 drought, after which it expressed a stark growth decline, i.e. drought legacies, which was not observed for oak. The PCGA revealed a clear differentiation in the grouping of drought responses between beech and oak, supporting the findings of the climate-growth analysis and the tolerance indices. Correlations of NDVI and ring-width indices (RWI) indicated that under normal climatic conditions NDVI variability is linked to the start of the growing season. This is in contrast to drought years, such as 2003, where summer NDVI mirrored the drought response of beech and oak. These results reveal beech to have both a higher sensitivity to summer temperature and SPEI and a higher susceptibility to drought events. Although, in the past high plasticity and adaptability to drought have been attributed to both beech and oak, our study assigns beech a higher risk than oak to suffer from anticipated increases in drought frequency and intensity as a consequence of climate change.

Genetic integrity is still maintained in natural populations of the indigenous wild apple species Malus sylvestris (Mill.) in Saxony as demonstrated with nuclear SSR and chloroplast DNA markers.

Malus sylvestris (Mill.) is the only indigenous wild apple species in Central Europe. Agriculture, forestry, and urbanization increasingly endanger Malus sylvestris natural habitats. In addition, the risks of cross‐hybridization associated with increase in the cultivation of the domesticated apple Malus × domestica (Borkh.) threaten the genetic integrity of M. sylvestris. The present study investigated the number of hybrids, genetic diversity, and genetic structure of 292 putative M. sylvestris that originate from five different natural M. sylvestris populations in Saxony, Germany. All samples were genetically analyzed using nine nuclear microsatellite markers (ncSSR) and four maternally inherited chloroplast markers (cpDNA) along with 56 apple cultivars commonly cultivated in Saxony. Eighty‐seven percent of the wild apple accessions were identified as pure M. sylvestris. The cpDNA analysis showed six private haplotypes for M. sylvestris, whereas three haplotypes were present in M. sylvestris and M. × domestica. The analysis of molecular variance (AMOVA) resulted in a moderate (ncSSR) and great (cpDNA) variation among pure M. sylvestris and M. × domestica individuals indicating a low gene flow between both species. The genetic diversity within the pure M. sylvestris populations was high with a weak genetic structure between the M. sylvestris populations indicating an unrestricted genetic exchange between these M. sylvestris populations. The clear distinguishing of M. sylvestris and M. ×domestica confirms our expectation of the existence of pure M. sylvestris accessions in this area and supports the argument for the implementation of preservation measures to protect the M. sylvestris populations in Saxony.

Mitochondrial Genome of Fagus sylvatica L. as a Source for Taxonomic Marker Development in the Fagales.

European beech, Fagus sylvatica L., is one of the most important and widespread deciduous tree species in Central Europe and is widely managed for its hard wood. The complete DNA sequence of the mitochondrial genome of Fagus sylvatica L. was assembled and annotated based on Illumina MiSeq reads and validated using long reads from nanopore MinION sequencing. The genome assembled into a single DNA sequence of 504,715 bp in length containing 58 genes with predicted function, including 35 protein-coding, 20 tRNA and three rRNA genes. Additionally, 23 putative protein-coding genes were predicted supported by RNA-Seq data. Aiming at the development of taxon-specific mitochondrial genetic markers, the tool SNPtax was developed and applied to select genic SNPs potentially specific for different taxa within the Fagales. Further validation of a small SNP set resulted in the development of four CAPS markers specific for Fagus, Fagaceae, or Fagales, respectively, when considering over 100 individuals from a total of 69 species of deciduous trees and conifers from up to 15 families included in the marker validation. The CAPS marker set is suitable to identify the genus Fagus in DNA samples from tree tissues or wood products, including wood composite products.

Haplothrips second instar larvae (Thysanoptera: Phlaeothripidae); character states and key to Central European species.

Descriptions and images of character states are provided of the second instar larvae of 16 species of Haplothrips. Specimens used are from Poland and surrounding countries, and an identification key is presented. The most important qualitative features concern colour, sclerotization and cuticular sculpture of some body parts, spiracle structure, setal lengths and type of setal apices.

Cinara splendens (Hemiptera: Aphididae: Lachninae)—First Record in Palaearctic Region

Nearctic aphid Cinara splendens (Gillette and Palmer, 1924) was collected on ornamental Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) in South Bohemia in 2009. It was the first record of this species in the Palaearctic region. The aim of this research was to study the bionomy of this species in Central Europe and to make descriptions of all available morphs, as previous morphological descriptions of C. splendens appeared to be incomplete. Six monitoring sites of this species were established in South Bohemia and were then regularly attended in the period of 2009–2019. The colonies of C. splendens were observed; its natural enemies and honeydew users were also registered. Aphids were collected for the microscope slide preparation, followed by the evaluation of thirty of the basic quantitative and seven qualitative morphological characteristics. Partial sequences of mitochondrial COI and nuclear EF-1α were used to confirm morphology-based identification and to compare samples from the Czech Republic with those of North American origin. Cinarasplendens survived successfully under new ecological conditions, but its population density remained quite low, except for 2009 and 2019, due to a synergistic effect of the dry weather and very high population density of the adelgid Gilletteella coweni (Gillette, 1907), which is a key pest of Douglas fir in the Czech Republic. The principle predators were coccinellid beetles, while the aphidophagous hover flies were less abundant. Together with a weak ability to migrate due to a low number of alate viviparous females in population, C. splendens cannot be a potential pest of P. menziesii in Central Europe.

Evidence of climate-induced stress of Norway spruce along elevation gradient preceding the current dieback in Central Europe

Effect of drought during 2017 and 2018 resulted in radial stem increment reduction to 78% and 61%, respectively, of the levels occurring in normal year 2016 in Central Europe. Norway spruce (Picea abies (L.) Karst.) is currently the most threatened commercial tree species in Central Europe. This is due to increased drought stress from advancing climate change as well as the species’ distribution outside its natural range. Tree water status and water movement through a tree are key parameters influencing tree growth and vitality. This study is focused on the growth and stress reaction of spruce to climatic conditions, analysing stem diameter variation along an elevation gradient (381–995 m a.s.l.) in the Czech Republic. Tree water deficit based on the zero-growth concept (TWD), calculated from high-frequency dendrometer records and the temporal dynamics of radial growth, was studied for 3 years (2016–2018). Two of these 3 years were affected by severe drought during the growing season. Contrary to our expectations, the observed TWD showed no clear linear decline with rising elevation. The most severe tree desiccation was observed in experimental sites at middle elevations of about 600 m a.s.l. Here, we show that both the timing and level of tree water deficit had an impact on annual stem radial increment (SRIannual). Severe drought had a substantial negative impact on SRIannual of Norway spruce in both 2017 and 2018. Drought conditions in 2017 and 2018 resulted in reduction of SRIannual relative to measurements for the wetter year in 2016 to 78% and 61%, respectively. We report the evidence that the current climatic conditions in the Central European region are not suitable for growing Norway spruce at lower and middle elevations and that forest management needs to react immediately to this situation.

The Dynamics of Beech Roundwood Prices in Selected Central European Markets

The European beech (Fagus sylvatica L.) is the most prevalent deciduous tree species in Central Europe. The implementation of sustainable, close-to-nature silvicultural practices increased the percentage share of beech in forest species composition, raising the economic significance of beech roundwood, especially in terms of revenues from timber sales. The elucidation of roundwood price mechanisms as well as long-term equilibrium relations between international markets may be helpful in calculating the profitability of beech roundwood production. The study material consists of quarterly time series of beech roundwood prices from Austria, Czechia, Germany, Poland, Slovakia, and Slovenia in the years 2005–2018. The price time series were described with a multiplicative model incorporating seasonal, cyclical, and irregular, as well as long-term trend components. The time series were decomposed using the Census X11 method. Stationarity was tested by means of the augmented Dickey–Fuller test (ADF) and the Kwiatkowski–Phillips–Schmidt–Shin test (KPSS). Cointegration was assessed using the Johansen and Engle–Granger methods. From 2005–2018, the highest mean beech roundwood prices were found for Austria (77.5 € m−3) and Germany, and the lowest for Poland and Slovakia. Roundwood prices were badly affected by the 2008/2009 financial crisis, which caused an approx. 27% decline. The prices of large-diameter beech logs exhibited seasonal fluctuations, typically reaching a maximum in Q1 and a minimum in Q3. The amplitude of those fluctuations was the highest in Slovenia in 2005 (10.1%), while in Czechia and Germany, seasonal effects increased over the period of study. The lowest seasonality was found in Slovakia and Austria (in the latter country it was not statistically significant). On an annual scale, cyclical changes generally accounted for the largest proportion of price variation, and were particularly pronounced in Poland (78.9%), Slovakia (78.6%), and Austria (69.2%). On the other hand, seasonal effects were predominant in the Slovenian (40.6%), German (34.1%), and Czech (33.3%) markets. In countries with price series of type I(0), simple correlation between stationary beech roundwood prices is positive and the strongest between Czechia–Poland and Czechia–Austria; on the other hand they are the weakest in the German market. In Slovakia and Slovenia with nonstationary price series, both Johansen’s and Engle-Granger’s cointegration tests indicated the absence of a long-term equilibrium between the analyzed beech timber markets. Results revealed integration between the prices of large-diameter beech logs in Czechia, Austria, and Poland. It should be mentioned that in this study, the time series of price used are rather short for long time cointegration analysis, which might prevent the proper detection of cointegration between all analyzed countries.

Successful without sex – the enigmatic biology and evolutionary origin of coralroot bittercress (Cardamine bulbifera, Brassicaceae)

Cardamine bulbifera (Coralroot Bittercress) is one of the Central European enigmatic plant species. Although the species is wide-spread all over Europe, no reproduction via seeds has ever been observed. Instead dispersal of vegetative leaf-axillary bulbs assures effective propagation. In our study we analyzed different life stages and factors affecting sexual reproduction and seek for unravelling the evolutionary origin of this polyploid species. We combined studies on pollen quality and fertility, pollen-stigma interactions, growth performance, and reproductive success with common garden experiments, controlled pollination and genotyping analysis (AFLPs). We also tested the interplay of resource allocation either into developing fruits and seeds or into reproductive organs generated by vegetative means. Cytogenetic analyses were conducted addressing variation in chromosome numbers and ploidy level. Phylogenetic relationships among possible parental lineages of Eurasian Cardamine species were reconstructed based on whole plastome sequences and the entire nuclear encoded rDNA cistron. We have shown herein that sexual reproduction of Cardamine bulbifera is hindered at various stages of reproductive development. We did not find any complete interruption of reproductive development except final embryo arrest. We detected low pollen germination rates and slow pollen tube growth. Less than 25 % of flowers matured into siliques with most often low-quality seeds; only 2% of those seeds developed towards early stages of germination but arrested before primary root formation. Results are independent from genotypes or vegetative propagation. Phylogenetic data demonstrate close relationships to C. quinquefolia and C. abchasica, but don’t indicate a hybrid origin involving distant species from other lineages. Cardamine bulbifera is a fully functional sexual plant with attractive flowers, nectar production, viable pollen, functional ovules and no signatures of a sporophytic incompatibility system. Highly reduced seed set and failure in seedling formation may be causally linked to a polyploid origin in the Caucasus region. Long-term survival has been achieved by rapid transition towards vegetative propagation and subsequent range expansion.

Changes in spring arrival dates of Central European bird species over the past 100 years

Over the past decades, spring temperatures have increased in temperate regions, which resulted in birds arriving earlier in spring. Nonetheless, the timing of some species’ spring migration relies on endogenous rhythms that are not affected by climate change. In this study, we analysed changes in the spring arrival dates of 36 bird species over two periods in 22 towns and villages in Southeast Hungary and West Romania. The first period covered the national spring migration counts between 1894 and 1926, while the second period took place between 2005 and 2019 and is based on our recent observation data. Our results show, that the average spring arrival dates of most long-distance migrant species have not changed significantly over the past 100 years. In contrast, in cases of medium and short-distance migrants, most species arrive earlier recently than in the past. This may be caused by the fact, that the migration habit of long-distance migrants is characterized by strong genetic determinants, so they can not react as quickly to the warmer spring weather in Europe as the medium and short-distance migrants. However, in cases of some long-distance migrants, the timing of spring migration changed due to the drying of wintering grounds.

Moving Away From Limiting Similarity During Restoration: Timing of Arrival and Native Biomass Are Better Proxies of Invasion Suppression in Grassland Communities

A challenge in many restoration projects, in particular when establishing de-novo communities, is the arrival and later dominance of invasive alien plants. This could potentially be avoided by designing invasion-resistant native communities. Several studies suggest achieving this by maximizing trait similarity between natives and potential invaders (‘limiting similarity’), but evidence supporting this approach is mixed so far. Others pose that the relative time of arrival by native and invasive species (‘priority effects’) could play a stronger role, yet this factor and its interaction with trait similarity is not fully understood in the context of ecological restoration. Thus, we hypothesised that multi-trait similarity would increase suppression of invasive species by native communities, and that the effect would be stronger when natives arrive first. We established two distinct communities of native central European grassland species based on native–invasive trait similarity, and then tested the introduction of invasive Ambrosia artemisiifolia and Solidago gigantea separately when arriving in the native communities at two times, i.e. sown either at the same time as the natives or two weeks after. For the traits selected, our data did not provide evidence for a limiting similarity effect, but rather supported priority effects. Both native communities more effectively suppressed invaders that arrived after the natives. In addition, the native community that produced the most biomass suppressed both invasive species more effectively than the most ecologically similar community. This effect of biomass revealed that prioritising native–invader ecological similarity can fail to account for other community characteristics that affect invasion resistance, such as biomass. Instead, native communities could be designed to enhance priority effects through the inclusion of early and fast developing species. We conclude that native community composition plays a significant role in the establishment success by invasive species, and resource pre-emption seems more significant than trait similarity. In terms of grassland restoration, native species should be selected based on plant traits related to fast emergence and early competitiveness.

New ecological and distributional data on Lewinskya shawii in France and its conservation in anthropogenic environments

Hugonnot, V. 2019. New ecological and distributional data on Lewinskya shawii in France and its conservation in anthropogenic environments – Herzogia 33: 188 –206.Lewinskya shawii is a southern and Central European and Mediterranean species occurring disjunctly in western North America. It has large populations in the Massif Central and Auvergne region, France, where numerous new localities are herein reported. Its national distribution in France is therefore updated. The ecology of the species was studied by analysing recent releves performed on a variety of phorophytes, mostly ash (Fraxinus excelsior) and beech (Fagus sylvatica). Lewinskya shawii occurs in urban and non-urban habitats, but to a large extent on well-illuminated trees in the open countryside, where it can be associated with rich epiphytic assemblages. Such trees are mostly pollards with Orthotricha growing abundantly on the trunk. In Auvergne, the anthropogenic environment is considered to be favourable to epiphytic Orthotricha s.l. It is suggested that light is a key factor for epiphytic assemblages in urban environments. Preliminary recommendations for the conservation of Lewinskya shawii and associated Red-Listed bryophytes in the small towns of Auvergne are given. Traditional management activities are considered capable of maintaining highly diverse epiphytic assemblages.

Thladiantha dubia Bunge in Bryansk Region: Distribution, Ecology, and Biochemical Characteristics

Thladiantha dubia Bunge is an East Asian species, a perennial herbaceous climbing vine, which naturally grows in the Russian Far East, in Northeast China, and on the Korean Peninsula. It is a secondary species in Central Europe, North America, South America (Ecuador), and Japan. Th. dubia is not an invasive plant for the majority of European countries. Th. dubia is bred in the European part of Russia as an ornamental plant, and it is found in a variety of disturbed habitats. In some regions of Russia, it has an invasive status. The distribution of Th. dubia in Bryansk Region was studied using grid mapping. The species was observed in 69 out of 223 examined squares (30.94%). Th. dubia occurs in disturbed habitats, wastelands, and homes. We have discovered and studied communities dominated by Th. dubia. The species forms monodominant resistant communities in anthropogenic habitats. On the basis of the analysis of geobotanical descriptions of the communities, we established the association Thladianthetum dubiae ass. nov. The formation of a monodominant community is possible owing to vegetative propagation and decrease in the illumination of the soil cover. Th. dubia secretes growth inhibitors, colins. Presumably, an invasion vector of Th. dubia is anthropochoria. Th. dubia is a potentially invasive species for Bryansk Region. The biomass of the plant is characterized by a good absorption capacity of some heavy metals, and it can be used as a soil remediator.

Initial Survival and Development of Planted European Beech (Fagus sylvatica L.) and Small-Leaved Lime (Tilia cordata Mill.) Seedlings Competing with Black Cherry (Prunus serotina Ehrh.).

Black cherry (Prunus serotina Ehrh.) is considered one of the most invasive tree species in central Europe and causes problems for both nature conservation and silviculture. Besides mechanical control treatments, a suggested control method to prevent its ongoing spread is to underplant shade-tolerant native tree species. Therefore, we combined two mechanical treatments, with underplanting of European beech (Fagus sylvatica L.) or small-leaved lime (Tilia cordata Mill.) on fenced and unfenced plots. After the first growing season, survival rates were evaluated, and selected seedlings were destructively harvested to analyze their growth performance and leaf morphology in association with the different light regimes resulting from mechanical treatments Survival rates for both seedlings were very high (>95%). Survival rates were higher on fenced plots than on unfenced plots, most likely as result of browsing. The mortality of F. sylvatica decreased with increasing light availability on fenced plots. The mortality of T. cordata did not change along the light gradient. After one vegetation period no differences with respect to biomass allocation could be detected along the light gradient. However, the specific leaf areas of both species responded similarly, decreasing with increasing light availability. In summary, both species were able to establish and survive in the dense P. serotina understory and might have the potential to outcompete the invasive alien species in the long run.

Juncus atratus Krock. (Juncaceae) rediscovered in Italy: a species deserving urgent conservation actions

The conservation status of plant species is an important tool for their effective conservation, but it has been evaluated only in a low number of taxa up to now. In this frame, the national assessment of Juncus atratus Krock., a Central European-South Siberian wet meadow species, is here provided. J. atratus is a rare and threatened species in Central Europe and has been listed as Regionally Extinct in the only Italian Region where it was previously known. The species has recently been rediscovered in Italy, in a different area (Castel S. Maria plain, Umbria Region), and at present, this is the only confirmed known location at national scale. An overview of its ecological and distributive characteristics is presented, considering both bibliographic sources and new data including its phytosociological context in the study area. According to the IUCN Criteria, the species is here ascribed to the category Critically Endangered (CR). The case of J. atratus is an emblematic example of the difficulty of providing exhaustive and reliable extinction risk assessment when knowledge on the species distribution is not complete.

Contrasting Leaf Trait Responses of Conifer and Broadleaved Seedlings to Altered Resource Availability Are Linked to Resource Strategies.

(1) Understanding tree seedling responses to water, nutrient, and light availability is crucial to precisely predict potential shifts in composition and structure of forest communities under future climatic conditions. (2) We exposed seedlings of widespread Central European tree species with contrasting leaf habit, deciduous broadleaves (DB) and evergreen conifers (EC), to factorial combinations of manipulated precipitation (100% and 50% of ambient), shade (40% and 60% of full sunlight), and nutrient availability (low and high NPK), and measured specific leaf area, C/N ratio, soluble sugars, starch and non-structural carbohydrate concentration, and δ13C of the leaves. (3) We found contrasting effects of water and nutrient availability on foliar traits of the two species groups: EC exhibited higher tolerance to low resource availability but also less plasticity in foliar traits, which is congruent with a “slow” resource strategy. In contrast, foliage of DB reacted particularly to altered nutrient availability, corresponding to a “fast” resource strategy with high foliar plasticity and rapid adjustments to resource fluctuations, commonly adopted by species with high growth rates. (4) We conclude that DB will respond to environmental change with foliar acclimation, while EC will either tolerate, to some extent, or shift their distribution range in response to environmental change.

Comparing experimental and field‐measured traits and their variability in Central European grassland species

AbstractQuestionsWhat are the relative effects of intra‐ and interspecific differences on variation in five functional traits measured in a garden pot experiment? Are species rankings based on trait means and intraspecific trait variability (ITV) stable across the garden experiment and field measurements?LocationExperimental garden and two grassland systems in Central Europe.MethodsWe measured five functional traits (plant height, leaf dry matter content [LDMC], leaf greenness, leaf thickness and specific leaf area SLA]) in 105 grassland species grown in a garden experiment subjected to fertilization, shading and waterlogging, complemented by a control. We also measured plant height, LDMC and SLA across grasslands in Germany, and used published values of the same traits from a field study in the Czech Republic. We then correlated speciesʼ trait means from different treatments in the experiment. We also compared garden‐ and field‐measured trait means and ITV in SLA, LDMC and plant height.ResultsMost variation in the experiment‐measured trait data was explained by interspecific differences, except for leaf greenness (where species explained less than 50% of the variance), and the treatments had little effect on close associations of trait means. Species rankings based on SLA and LDMC, but not plant height, were stable across garden and field measurements. Though garden and field‐measured ITV were positively associated with each other, the associations were not significant.ConclusionsOur study indicates that species can be stably ranked based on SLA and LDMC means across different datasets (experimental and field‐based). To what extent species vary in their functional traits under field conditions can be, however, less well predicted from experimentally measured ITV. Garden‐measured differences in ITV should be thus used with caution when associated with species’ performance and distribution patterns explored in the field.

Erythraeid mites (Acariformes: Actinedida: Erythraeidae) of the Greater Caucasus region of Azerbaijan

The summary is given in the article about the observed species of the Erythraeidae Robineau- Desvoidy, 1828 mites in the Greater Caucasus Region of Azerbaijan. 25 species belonging to 8 genera of 5 sub-families have been found. Among them 1 sub-family (Balaustiinae Grandjean, 1947), 4 genera (Erythraeus Latreille, 1806, Curteria Southcott, 1961, Balaustium v.Heyden, 1826, Neobalaustium Willmann, 1951) and 22 species are new for the Caucasian fauna. 2 subfamilies (Callidosomatinae Southcott, 1961 and Abrolophinae Witte, 1995), 2 genera (Charletonia oudemans, 1910 and Abrolophus Berlese, 1891) and 1 species (Charletonia cardinalis (Pallas, 1772)) are new for the studied area. Abrolophus Berlese, 1891 genera are rich with species, 8 species have been found. The found species are spread over the altitudes and landscape zones, landscapes and forest biotopes. Also, the zoogeographic analysis of the erythraeid mites was carried out and they were divided into ecological groups. The studies show that the base of the fauna of the Erythraeidae Robineau-Desvoidy, 1828 mites in the Greater Caucasus region consists of 3 zoogeographic groups: European species (9 species), Central European species (5 species), Holarctic species (4 species).

Pleistocene herpetofaunal studies in Serbia (Balkan Peninsula, SE Europe): State of the art and perspectives

The country of Serbia is situated on the Balkan Peninsula and has a moderate continental climate. Dramatic tectonic activity in the early Miocene generated two main mountain ranges and led to the retreat of Paratethys. This meant the Balkan Peninsula became a crossroads for many migrating species. Currently, the majority of central European species, along with some Mediterranean, and even Euro-Siberian taxa can be found in Serbia. Fossil records from caves reveal changes in fossil fauna from the Pleistocene to Holocene. There is evidence that the distinct configuration of the terrain in the Balkans led to many isolated areas, enabling large mammal species, together with Neanderthals that were living in the area, to find refuge and survive longer than in the rest of Europe. The best fossil associations containing small vertebrates come from the Baranica, Hadži Prodanova, Pešturina, and Smolućka caves. Based on available numerical dating, an attempt has been made to fit these within the chronological context of the Mousterian-Aurignacian-Gravettian cultural succession. The stratigraphy of the layers corresponds to the so-called MIS 5 to MIS 2 (i.e., from 70,000 to 14,000 years ago). This paper presents a review of the herpetofaunal findings from Serbia, and analyses the data collected. Statistical approaches, involving hierarchical clustering and correspondence analysis, have been used on the fossil amphibian and reptile assemblages. As associated context is often not sufficient, small mammal assemblages have been used as a comparative proxy for reconstructing the palaeoclimate and palaeoenvironment, through the application of taxonomical habitat indexes and bioclimate analysis. The overall analysis reveals that the herpetofaunal composition experience substantial change between MIS 3 and MIS 2, when there were a loss of diversity and the concurrence of species adapted to cold climates and environments, in accordance with the glacial cycle.

Impact of species mixture on the stiffness of European beech (Fagus sylvatica L.) sawn timber

European beech (Fagus sylvatica L.) is the most commonly occurring deciduous tree species in Central Europe. Because of its competitiveness and (morphological) variability, it occurs in different species mixtures. The aim of the present study was to determine whether, and to what extent, the internal wood properties of European beech are affected by species mixture. Logs obtained from 100 beech trees from the low-mountain Spessart region in Germany were sampled and subdivided into five equal groups representing different mixture types: pure beech stands and four beech stands with the following tree species, respectively: Pseudotsuga menziesii, Picea abies, Pinus sylvestris and Quercus petraea. After logging and sawing, the boards were graded according to strength. For this purpose, the dynamic modulus of elasticity (MOEdyn) was determined. The MOEdyn, which is a relevant property for wood quality in the construction sector, was regressed against various independent variables, such as cambial age or mixture type. Relevant differences in wood quality were observed between mixture types. Beech trees in monocultures had the highest stiffness. In particular, species mixture with the light-demanding Quercus petraea or Pinus sylvestris yielded a significant reduction in the stiffness of the beech timber (–10% and –14%, respectively). Therefore, beech glued laminated timber of higher strength classes (≥GL 40c) was not viable using beech from these mixture types. The findings of this study also revealed significant effects of axial board position and cambial age on MOEdyn. The present transformation of forests into mixed forests affects the quality of the wood. Future research should focus on the dependencies between varying growth conditions—also caused by climate change—and wood formation.