Syntaxonomy and phytogeographical differentiation of the Fagus woods in the Southwest Balkan Peninsula

Abstract. Up to now the syntaxonomy of the Fagus woods of the southern Balkans is far less known than that of beech communities in the northwestern part of the Balkan Peninsula and in central and western Europe. A set of 607 phytosociological relevés from southeastern Serbia, the Former Yugoslav Republic of Macedonia, and northern and central Greece was subjected to numerical classification and ordination. These results were used for a syntaxonomic revision of Fagus, Fagus‐Abies and Fagus‐Acer woodland communities of the southwestern Balkans. The Doronico columnae‐Fagenion (seven associations from Serbia, the F.Y.R.O.M., and high altitudes in northern Greece) and the Doronico orientalis‐Fagenion (four associations from northern and central Greece) were distinguished. The results of ordination by Canonical Variates Analysis (CVA) showed a very distinct phytogeographical pattern of differentiation between community types. The floristic composition of Fagus woods changes markedly along the north‐south gradient. The share of Subbalkan, Balkan, Submediterranean and Mediterranean species increases significantly towards the south, while the Central‐European, European, Euro‐Siberian, Euro‐Asiatic and Circumpolar species decrease in the same direction. The syntaxonomic differentiation of the Fagus woodlands and their classification into regional suballiances reflects this gradient. With the rise in altitude, the number of Balkan, Mediterranean, Submediterranean, European and Euro‐Asiatic species declines.     

Composition,dynamics and disturbance regime of temperate deciduous forests in Monsoon Asia

Temperate deciduous forests in Monsoon Asia are classified into three forest types which differ in floristic composition, dynamics and disturbance regime. The cool temperate mixed deciduous broadleaf/conifer forest, dominated by Quercus spp. (mainly Q. mongolica or Q. crispula) and conifers, is distributed in northern parts of the temperate zone. The cool temperate deciduous forest, dominated by Fagus crenata, is distributed in Honshu, Japan under a humid climate through the year. The warm temperate deciduous forest dominated by Quercus spp. (mainly Q. acutissima or Q. serrata) occurs in the continental areas, the Korean Peninsula, and the Pacific Ocean side of Japan. The species diversity of cool temperate deciduous forest was lower than the other two types because of the intensive dominance of Fagus crenata. The disturbance regimes also varies among the three types; small scale treefall gaps are prevailing in the cool temperate deciduous forest, while larger scaled disturbances are important in the other two forest types. Fire seems to be important in the warm temperate deciduous forest, and both fire and large scale blowdowm seems important in the cool temperate mixed broadleaf/conifer forest. These differences in forest composition and disturbance regimes associated with climatic conditions and ancient human impacts have a close analogy with the Northeastern Hardwood forests in North America.     

Geographical and ecological differentiation in Greek Fagus forest vegetation

Question: Which are the gradients of floristic differentiation in Greek beech (Fagus sylvatica) forests? Which is the role of geographical and ecological factors in this differentiation? Location: Beech forests of the plant geographical regions Northeast, North Central and East Central Greece. Methods: A total of 1404 published and unpublished phytoso‐ciological relevés were used in the analyses. TWINSPAN and DCA were applied to classify and ordinate the relevés. Altitude, Indicator Values of relevés and their X and Y coordinates were used in a posteriori interpretation of the ordination axes. Kendall's correlation coefficients were calculated between DCA relevé scores and explanatory variables. Multiple linear regression was used to partition the variation explained by the first two DCA axes, between the geographical and the ecological variables. Results: Classification resulted in 14 vegetation units defined by species composition. Two types of gradients, ecological and geographical, were revealed by the DCA of all releves. The partition of the variation accounted for by the first and second DCA axis was attributed mainly to ecological and geographical variables, respectively. Conclusions: Beech forests of northeast and Central Greece show phytogeographical differences, while ecologically similar vegetation units occur in both regions. A west‐east gradient is revealed in Greek beech forest vegetation. The extent of the study area, its position along regional gradients and the comprehensiveness of the data set that is analysed determine the types of the gradients which can be revealed in a vegetation study.     

Beech forest communities in the Nordic countries – a multivariate analysis

In this study we present the first comprehensive multivariate analysis of beech (Fagus sylvatica) forest communities in the Nordic countries. The history of beech and beech forests in Scandinavia are described. In the north, the species is climatically restrained and, at present, restricted to Denmark and the southern parts of Sweden and Norway.More than 2000 sample plots were compiled, partly from literature, partly from new and unpublished data. The material included more than 20 studies of beech forests, often recorded by different non-standardised sampling designs. Therefore, prior to data analysis, a large number of plots had to be excluded to reduce the heterogeneity of the data. Only such sample plots were considered that showed a predominance of Fagus sylvatica in the canopy, that had a size within the interval of 16–100 m2, and that could be located by geographical coordinates. All species abundance values were transformed into simple species presences, and data from different vegetation layers were merged into one.A TWINSPAN cluster analysis resulted in 15 types. Three main communities with several sub-communities and varieties can be distinguished: (1) the Fagus sylvatica-Fraxinus excelsior-Stachys sylvatica community on the most basic and fertile soils, (2) the Fagus sylvatica-Corylus avellana-Galium odoratum community on moderately fertile and acid soils, and (3) the Fagus sylvatica-Sorbus aucuparia-Deschampsia flexuosa community on very acid and oligotrophic soils. Synonyms in the recent literature on Nordic beech forests to these communities are given. An ordination with the program DECORANA confirmed the primary significance of soil acidity and nutrient status for community differentiation.p>     

Migration, invasion and decline: changes in recruitment and forest structure in a warming-linked shift of European beech forest in Catalonia (NE Spain)

Altitudinal upward shifts of species' ranges have occurred across a wide range of taxonomic groups and geographical locations during the twentieth century in response to current climate warming. However, actual data of plant species' altitudinal shifts are still scarce and not always clear. Here we provide a more detailed investigation of a previously reported European beech Fagus sylvatica forest altitudinal shift in the Montseny Mountains (Catalonia, NE Spain) now based on field photographic survey and on the population age structure and the recruitment patterns in the high Fagus limit (HFL), the central forest area (CFA) and the low Fagus limit (LFL). Monitoring of the lowest altitudinal range shows that beech forest is being progressively replaced by Mediterranean holm oak forest. Holm oaks are characterized by recruitment rates more than three times higher than those of beech in the LFL in the last decades. The percentage of young individuals in the LFL is only half that in the HFL and CFA. In the highest altitudinal range, present day and early 20th century photographs show that the HFL has gained density and has shifted altitudinally upwards, advancing with establishment of new, vigorous outpost trees (13 individuals per each 100 m of tree-line). They are mostly (89%) younger than 35 yr old and mostly (97%) located up to 70  m (with a few up to 105 m) ground surface distance above the current tree line (36–51 m altitude) at the highest altitudes (1600–1700 m). The beech forest upward shift is a likely consequence of warming, but land-use practice changes (cessation of burning by shepherds) have made it possible. These changes in vegetation distribution and population structure constitute a new indication of the complex global change effects on life in mountain ecosystems.     

Use of ISSR-markers for determination of convergent evolutionary relations in Fagus genus

Genetic relationships between members of Fagus genus were assessed using ISSR markers and amplification. The taxonomic status of Fagus sylvatica L. and Fagus orientalis LYPSKY. species in Ukraine has been ascertained more precisely. Intraspecies mean genetic distances were compared according to Nei & Li and respective dendrogram was constructed with the complete joining method.     

Niche characteristics of Danish woody species as derived from coenoclines

Abstract. A main floristic coenocline is extracted from a Danish forest vegetation data set with Detrended Correspondence Analysis. Huisman‐Olff‐Fresco (HOF) modelling of 262 species occurrences relative to site scores along the coenocline is compared with Gaussian and Generalized Linear Modelling. HOF models allow for responses of variously skewed forms, which may result from interspecific interactions. Most species have symmetric (60%) or skewed (29%), and only few species have flat or monotone response curves. This provides evidence for the generality of unimodal plant species response curves, provided the gradient in question comprises a sufficient amount of compositional turnover. The Gaussian niche width is correlated with density of optima and probability of occurrence of the species. Detailed analysis of HOF estimates for 28 woody species indicates that early succession species such as Pinus sylvestris and Populus tremula have wider niches than middle to late successional canopy species such as Alnus glutinosa, Carpinus betulus, Fagus sylvatica, Fraxinus excelsior, Quercus robur and Tilia cordata. A marked overlap in niche range along the coenocline is interpreted in terms of species competition. Rubus idaeus intrudes into the niches of all other shrub species. Several canopy tree species, such as Fagus sylvatica, Fraxinus excelsior and Quercus robur overlap more than 60% of the ranges of all other species, while their internal overlaps are fairly equal, presenting evidence for their likely co‐existence given more natural forest conditions. The combined analysis of coenoclines with HOF modelling of species behaviour is the most robust among the compared methods for estimating model parameters and niche characteristics of plant species. It is recommended for future ecological studies.     

Floristic diversity in fragmented Afromontane rainforests: Altitudinal variation and conservation importance

Question: How does the floristic diversity of Afromontane rainforests change along an altitudinal gradient? What are the implications for conservation planning in these strongly fragmented forest areas that form part of the Eastern Afromontane Biodiversity Hotspot? Location: Bonga, southwestern Ethiopia. Methods: Based on evidence from other montane forests, we hypothesized that altitude has an effect on the floristic diversity of Afromontane rainforests in southwestern Ethiopia. To test this hypothesis, detailed vegetation surveys were carried out in 62 study plots located in four relatively undisturbed forest fragments situated at altitudes between 1600 m and 2300 m. Floristic diversity was evaluated using a combination of multivariate statistical analyses and diversity indices. Results: Ordination and indicator species analyses showed gradual variations in floristic diversity along the altitudinal gradient with a pronounced shift in species composition at ca. 1830 m. Upper montane forest (>1830 m) is characterized by high fern diversity and indicator species that are Afromontane endemics. Lower montane forest (<1830 m) exhibits a greater diversity of tree species and a higher abundance of the flagship species Coffea arabica. Conclusions: Our results provide crucial ecological background information concerning the montane rainforests of Ethiopia, which have been poorly studied until now. We conclude that both forest types identified during this study need to be considered for conservation because of their particular species compositions. Owing to the high degree of forest fragmentation, conservation concepts should consider a multi‐site approach with at least two protected areas at different altitudinal levels.     

Pollen from Lake Sedmo Rilsko reveals southeast European postglacial vegetation in the highest mountain area of the Balkans

A lacustrine sequence from Lake Sedmo Rilsko (altitude 2095 m) in the northwest of Rila Mountain, Bulgaria, was analysed on the basis of 84 pollen spectra and three ¹⁴C accelerator mass spectrometry dates. The lower part of the sequence (413–530 cm) corresponds to the Late-glacial. Three phases, two stadial and one interstadial, are characterized by the dominance of mountain–steppe herb vegetation composed of Artemisia , Chenopodiaceae and Poaceae, with single trees of Pinus and shrub land of Juniperus and Ephedra . The identification of pollen grains of Abies , Quercus robur -type, Corylus , Acer , Fagus and other mesophilous trees suggests that they survived the harsh Late-glacial conditions in refuges below an altitude of 1000 m, where moisture was sufficient for their growth. In the early Holocene period, Betula forests at high altitudes and, below them, closed deciduous forests with Quercus , Tilia , Ulmus and Corylus , occurred from 11800 until approx. 6700 cal. BP. The formation of the coniferous belt dominated by Pinus sylvestris , Pinus peuce and Abies alba lasted from between 6700 and 5000 cal. BP. The forest dynamics in the Subboreal and the Subatlantic ended with the invasion of Fagus sylvatica and Picea abies after approx. 4500 and 3300 cal. BP, respectively. Indications of anthropogenic activities, expansion of agriculture in the lowland foothills, and livestock grazing in the mountain meadows and pastures, are clearly evident from the pollen diagram from 2400 cal. BP onwards.     

Brazilian Páramos I. An introduction to the physical environment and vegetation of the campos de altitude

Aim The campos de altitude are a series of cool-humid, grass-dominated formations restricted to the highest summits of the southeastern Brazilian Highlands. Relatively little is known of the ecology, biogeography, or developmental history of this archipelago of mountaintop formations. This contribution presents an overview of our present state of knowledge with respect to the past and present physical environment and vegetation of the campos de altitude. The aim is (1) to introduce an international audience to the natural history of these diminutive yet important ecosystems, and (2) to provide the background for a series of forthcoming contributions that will treat the ecology of the campos de altitude and explore physical and biotic relationships between these ‘Brazilian páramos’ and similar formations in the high mountains of equatorial South and Central America. Location Beginning at altitudes of 1800–2000 m, the campos de altitude are found atop the highest summits of the main ranges of the southeastern Brazilian Highlands, between the states of Santa Catarina and Minas Gerais/Espírito Santo. Methods Drawing upon both original data and previously published results, this contribution reviews what we presently know about the physical environment and vegetation of the campos de altitude, in the context of geographic setting, geology, palaeoclimatology and palaeobotany, modern climate, modern vegetation, and conservation. Results and main conclusions Uplift of the southeastern Brazilian ranges to altitudes high enough to support orographic grasslands may have occurred as early as the middle- to late-Tertiary; pollen records show that campos de altitude have been extant on southeastern summits at least since the Late Pleistocene. The present-day climate of the campos de altitude is cool and (per)humid, but patterns of rainfall, temperature, and frost are distinctly seasonal. Although the flora of the campos de altitude is highly diverse and characterized by a high degree of endemism, the campos de altitude maintain strong floristic similarities to equatorial alpine formations of the Andean and Central American Cordillera; these similarities also extend to climate, soils, and vegetation physiognomy. Anthropogenic fires and grazing are widespread in the campos de altitude and probably contribute significantly to the modern structure of vegetation communities.     

Danish forest development during the last 3000 years reconstructed from regional pollen data

Most present Danish forest types are a direct result of recent silvicultural practice. We use fossil pollen data converted into estimates of tree abundance to map the development of forest types during the last 3000 radioearbon yr. The forest types were clusters in an artificial neural network based on all available European Holocene pollen data. Diverse deciduous forest types found 3000 yr ago were replaced by less diverse Fagus -dominated types over a period of 2000 yr. The present day map contained many new combinations of tree species, dominated by Picea and Pinus. The association between the increase in non-forest communities and establishment of Fagus suggests that anthropogenic activity has accelerated the loss of species-rich deciduous forest with abundant .Alnus, Corylus, Quercus and Tilia. We conclude that the natural forest composition of Denmark would be deciduous forest today with a significant presence of Fugus sylvatica. Recent forest development has created a break in compositional continuity with the past that is unnatural and has posed problems for forest-dependent biota.     

Interactive influences of climate and parent material on soil microbial community structure in Bornean tropical forest ecosystems

Climate and parent material strongly control vegetation structure and function, yet their control over the belowground microbial community is poorly understood. We assessed variation in microbial lipid profiles in undisturbed forest soils (organic and surface mineral horizons) along an altitudinal gradient (700, 1,700, and 2,700 m a.s.l. mean annual temperature of 12–24°C) on two contrasting parent materials (acidic metasedimentary vs. ultrabasic igneous rock) in Mt. Kinabalu, Borneo. Soil organic carbon and nitrogen concentrations were generally higher at higher altitudes and, within a site, at upper soil horizons. Soil pH ranged from 3.9 to 5.3, with higher values for the ultrabasic soils especially at higher altitudes. The major shifts in microbial community structure observed were the decline in the ratio of fungal to bacterial lipid markers both with increasing soil depth and decreasing altitude. The positive correlation between this ratio with soil C and N concentrations suggested a strong substrate control in accord with the literature from mid to high-latitude ecosystems. Principal component analysis using seven groups of signature lipids suggested a significant altitude by parent material interaction—the significant difference in microbial community structure between the two rock types found at 2,700-m sites developed on weakly weathered soils diminished with decreasing altitude towards 700-m sites where soils were strongly weathered. These results are consistent with the hypothesis that parent material effect on soil microbial community (either directly via soil geochemistry or indirectly via floristic composition) is stronger at an earlier stage of ecosystem development.     

Flora and vegetation of rocky outcrops/cliffs near the Hyrcanian forest timberline in the Mazandaran mountains,northern Iran

Due to their numerous endemic/sub‐endemic and rare plant species, rocky outcrops and cliffs, particularly those occurring at the timberline and forest/steppe ecotones of the Hyrcanian area, are considered as among the most important and fragile ecosystems in Iran. As a representative of such ecosystems, one of the last remnants of relatively undisturbed timberline and ecotone areas of the central Hyrcanian region was selected for phytogeographical, floristic and vegetation analyses. The flora and vegetation of rocky outcrops and crevices at altitudes of 2500–3000 m a.s.l. was surveyed by 40 relevés of 25 m² surface area. A total of 215 vascular plants belonging to 55 families and 150 genera were identified in the different vegetation types. Hemicrytophytes (55.8%) were the dominant life form and Euro–Siberian/Irano–Turanian biregional plants (28.2%) were the most common chorotype at the study sites. A phytogeographical analysis indicated that Euro–Siberian elements (including Hyrcanian endemics) precede other uniregional chorotypes in the timberline and upper‐mountain parts of the central Hyrcanian area. The Caucasus, an important biodiversity hotspot close to Iran, has a considerable number of taxa in common with the Irano–Turanian floristic regions. Five vegetation types were identified using a modified TWINSPAN procedure and subsequently analysed by indirect gradient analysis applying both species‐related (species richness, life form and phytogeographical elements) and topographic/bedrocks features of the studied relevés. The analysis revealed that the vegetation of the area is mainly affected by altitude, heat index, northness, slope inclination and bedrock features.     

Distribution and structural-functional attributes of trees in the high altitude zone of Central Himalaya,India

Patterns of tree species distribution and their structural-functional features were studied along an altitudinal gradient in the Indian Central Himalaya. The forest vegetation falls within three formation types: low to mid-montane sclerophyllous, broad-leaved forests; mid-montane deciduous forests; and high-montane mixed stunted forests. Deciduous tree species formed a considerable (49%) portion of the high altitude forests between 1500–3300 m. The upper limit of forests ranges from 3000 to 3300 m, and three taxa are commonly found at tree line: an evergreen, needle-leaved gymnosperm (Abies pindrow Spach.), an evergreen, broad-leaved sclerophyllous oak (Quercus semecarpifolia Sm.), and a deciduous, broad-leaved birch (Betula utilis Don).The high altitude forests differed from the low altitude forests of Central Himalaya in their greater proportion of microphanerophytes. Vernal flowering is common at this elevation in Central Himalaya. In general, in their elevational distribution and structural-functional attributes, these high altitude forests are similar to other forests of cool temperate zones in Himalaya.     

大别山南坡森林植物群落物种多样性及其与海拔因子的关系

大别山地区植物资源丰富,区系组成复杂且起源古老,为连接华东、华北和华中三大植物区系的纽带,也是我国重要的生物多样性保护和水源涵养生态功能区。采用样方法,在大别山南坡的多枝尖、庵基坪和麒麟沟3个地区,沿着不同海拔高度选取了具有代表性的森林植物群落进行研究,从不同植物群落类型和层次的物种多样性、均匀度和丰富度及其与海拔因子的关系等方面,对大别山南坡的森林植物群落物种多样性进行综合分析。结果表明:1. 共记录有植物108科270属449种,划分为20个森林植物群落类型;2. 森林植物群落各层次物种丰富度表现为草本>乔木>灌木;Shannon-Wiener多样性指数和Simpson多样性指数呈现出乔木>灌木>草本;Pielou均匀度指数变化较为复杂;3. 森林植物群落各层次的物种丰富度随海拔升高而下降;Shannon-Wiener指数和Simpson指数也表现为随着海拔升高而下降,但草本层在1400m之后有上升的趋势。Pielou指数在乔木层中表现为随着海拔的升高而下降,在草本层中表现为先下降后出现上升,在灌木层中则随着海拔的升高而上升,但其波动更为剧烈。本研究对大别山南坡森林植被大范围的采样观测研究,能够全面的展现大别山南坡森林植物的种类分布、空间组成等整体概况及其与海拔因子的关系,能为以后大别山南坡生物多样性的保护提供较为全面真实的数据,从而为大别山地区生物多样性的保护和可持续利用提供理论依据和实践意义。     

The intercalibration of the Hellenic Evaluation System for Mediterranean rivers of type R-M1 and R-M2 at Northern and Central Greece

The present paper deals with the intercalibration of the Hellenic Evaluation System (HESY) boundaries for the ecological quality of Greek rivers (Northern and Central Greece) [small size and mid altitude (type R-M1) and medium size and low altitude (type R-M2)] with the officially quality boundaries set by the European Commission and the quality boundaries of the multimetric indices STAR_ICMi and ICMi7RM based on the Mediterranean Guadalmed benchmark database. Benthic macroinvertebrates were used as biological elements for the HESY and the multimetric indices STAR_ICMi and ICMi7RM. The Hellenic dataset of benthic macroinvertebrates came from previous data of the Laboratory of Zoology, Department of Biology (Aristotle University of Thessaloniki), consisting of 129 samples (41 reference samples) from Northern and Central Greece. Both the multimetric indices performed well against the stressor gradient and indicated strong relationship to the Hellenic Evaluation System. Therefore, they could both be used for the intercalibration process and the assessment of the ecological quality in Northern and Central Greece. Moreover, the use of the HESY in Greek territory (a) can produce comparable results to the STAR_ICMi, which is also used by the Central European and Baltic GIG, assessment method and (b) may be considered reliable in other river types (e.g. R-M3) for which there has not been an intercalibration process or even intercalibration metrics in Europe, due to the lack of reference conditions.     

Differences in the vegetation of the North Iberian Peninsula during the last 16,000 years

The dynamics of vegetation in the North Iberian Peninsula have been historically established from peaty and lacustrine records obtained in strongly continental mountainous areas. Pollen records located in areas with a more oceanic climate, have allowed a more precise evaluation of the changes and differences in the vegetation development of the various biogeographical areas in the North Iberian Peninsula, during the Late-glacial and Holocene. It was found that: (1) The vegetation of the Cantabrian–Atlantic province in northern Iberian Peninsula responded to climatic changes during the last 16000 years. (2) Tree vegetation declined during the Oldest Dryas, with steppe vegetation in the interior and cryophilous vegetation along the coast. (3) During the time of the Lateglacial Interestadial, lowlands, arboreal vegetation was dominant in the landscape (Pinus, Betula, Quercus, Corylus). (4) During the Younger Dryas the differences between coast and interior are less obvious. (5) During the Holocene oceanic decidious forests of Quercus robur, Corylus avellana, Tilia sp. and Fagus sylvatica were present along the coast. At low altitudes, in the interior, forests of Quercus robur / pyrenaica, enclaves of pine woods and Mediterranean types of forest (Quercus ilex, Olea europea) were present. At higher altitudes Pinus (P. sylvestris and P. uncinata) or mixed forests of Pinus and Betula were dominant.     

The immigration of Fagus sylvatica L. and Picea abies (L.) Karst. into a natural forest stand in southern Sweden during the last 2000 years

The continental scale migrations of Fagus sylvatica L. and Picea abies (L.) Karst. are under a broad climatic control, but disturbance and local factors influence the immigration of these species into individual forest stands. Palaeoecological analysis of a small forest hollow in the boreo-nemoral zone of southern Sweden has shown that a forest stand with largely unbroken forest continuity resisted immigration of Fagus for almost 1000 years. Two fires about 950 and 330 years ago were the disturbing factors that facilitated eventual Fagus immigration. Picea immigrated and achieved co-dominance in a single generation, without resistance from the existing forest. Thus migrational lag is demonstrable for Fagus but not Picea . The immigration of these two dominating species coupled with a severe reduction in tree species diversity has resulted in a total change in forest competition during the last few centuries despite the maintenance of a structural forest continuity. Some of these changes are attributable to changes in the grazing regime, but the forest stand is as close to «natural>> conditions as can be found in S. Sweden.     

The Balkan wet grassland vegetation: a prerequisite to better understanding of European habitat diversity

The knowledge of broad-scale floristic variation in wet grasslands, which are endangered throughout Europe, is still limited and some regions have remained unexplored so far. In addition, hitherto published phytosociological studies were concentrated at the national level and therefore national vegetation classifications are not consistent with each other. In order to overcome these shortcomings of traditional phytosociology, we gathered original data from Bulgaria and analysed them together with the data from Central Europe. We further analysed major compositional gradients within Bulgarian wet grasslands and changes in species richness along them. We sampled 164 wet grassland vegetation plots throughout Bulgaria. We further prepared a restricted data set of wet grasslands from Central-European phytosociological databases. Both data sets were merged and classified by modified TWINSPAN. Four distinct vegetation types were differentiated. Even if they correspond with traditional alliances, which are primarily drawn as geographically defined units in Western and Central Europe (sub-Mediterranean Trifolion resupinati, sub-continental Deschampsion cespitosae and Molinion caeruleae and sub-oceanic Calthion palustris), they all occur in Bulgaria. When more precise classification was applied, two types of sub-Mediterranean wet grasslands and one high-altitude type of Calthion grasslands were detected solely in Bulgaria. DCA analysis showed that altitude is a dominant gradient controlling variation in Balkan wet grasslands. The second DCA axis was interpreted as the gradient of nutrient availability. Species richness shows skewed-unimodal trends along both major gradients, with the highest species richness in intermittently wet nutrient-limited grasslands. Tukey post-hoc test of altitudinal differences amongst vegetation types is significant for all pairs of clusters, suggesting that altitudinal differentiation is responsible for co-occurrence of nearly all European types of wet grasslands in Bulgaria. Our results suggest that (1) climate is an important factor for the diversity of wet grasslands; (2) Balkan vegetation of middle altitudes matches with that of Central Europe, whereas that of the lowest altitudes corresponds rather to the sub-Mediterranean region and high mountains are specific; (3) upward shift of Central-European vegetation types in southern Europe, so often described in forest vegetation is also evident for grassland vegetation and (4) the high diversity of Balkan vegetation is determined by a diverse relief enabling confluence of habitats possessing different climatic conditions.     

Habitat preferences of Hericium erinaceus in Slovakia

Distribution patterns, ecology and habitats of Hericium erinaceus in Slovakia are presented, together with an indication of its population size and dynamics as driven by the type of substratum the fungus feeds on. Basidiomata have been recorded both on living and dead trees, predominantly on oaks (Quercus spp.) but also on European beech (Fagus sylvatica), and at altitudes ranging from 103 to 753 m, which in Slovakia corresponds to warm hilly and upland beech-oak forests. Standing trunks were a more common substratum than fallen trunks. Although the fungus tends to occur in old-growth forests, nearly half of the observations were from managed forests. Given the observed distribution, we conclude that H. erinaceus is not a strict indicator of intact old-growth forests in Slovakia.