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The CLUE-S model is a popular choice for modelling land use and land cover change from local to regional scales, but it spatially allocates the demand for only the total cover of each land class in the predicted map. In the present work, we introduce a CLUE-S variant that allocates demand at the more detailed level of land type transitions, the trans-CLUE-S model. We implemented this extension algorithmically in R, without the need of new parameters. By processing each row of the land transition matrix separately, the model allocates the demand of each land category’s transitions via the CLUE-S allocation routine for only the cells which were of that category in the map of the previous time step. We found that the trans-CLUE-S model had half the total and configuration disagreement of the CLUE-S predictions in an empirical landscape, and in simulated landscapes of different characteristics. Moreover, the trans-CLUE-S performance was less sensitive to the number of environmental predictors of land type suitability for allocating demand. Although trans-CLUE-S is computationally more demanding due to running a CLUE-S allocation for each land class, we appended the solution of a land-use assignment optimisation problem that facilitates the convergence and acceleration of allocation. We additionally provide R functions for: CLUE-S variants at other levels of demand resolution; random instead of environment-based allocation; and for simulating landscapes of desired characteristics. Our R code for the models and functions can contribute to more reproducible, transparent and accurate modelling, analysis and interpretation of land cover change.HighlightsThe trans-CLUE-S model employs demand at the finer level of land type transitionsThe trans-CLUE-S predictions were twice more accurate than the CLUE-S model’sThe trans-CLUE-S accuracy was less dependent on the amount of environmental dataAlgorithmic addition of a land assignment task enabled and sped up full convergenceR code is provided for our models and auxiliary functions

Land abandonment is one of the main drivers of land use/land cover (LULC) change across Europe, which has already led to a significant loss of open habitats, threatening species hosted in them. We investigated LULC changes for a period of 70 years in a mountainous area of central Greece (Mt Agrafa) by mapping its land cover for the years 1945, 1996 and 2015, calculating transition matrices of land cover classes and performing intensity analysis at different levels. Subareas of the study area, with different population trends, were compared in regard to their LULC change trends. Possible drivers of LULC changes were explored by means of Random Forest modeling, and landscape metrics were calculated to assess their trends. Our results showed great changes in LULC class cover, significant shrinkage of open habitats, accelerated rates of change in the recent period and no differences in LULC change patterns in relation to different population trends. Variables expressing favorability of ecological conditions for forest establishment or probability of farmland abandonment were found as more important drivers of the spatiotemporal distribution of LULC classes, while landscape metrics revealed certain trends. Our main conclusion is that land abandonment and the subsequent vegetation succession are going through a semifinal stage, before their completeness and the almost absolute dominance of the forest, and repopulation of the countryside cannot unconditionally ensure any halting effect on the land abandonment process.

The size and shape of tree leaves and their variation within the canopy are the result of both physiological plasticity and an overall adaptive strategy against unfavourable environmental conditions. In this study, diversity patterns at leaf morphological traits will be described within and among populations of trees with different phylogenetic background. Beech (Fagus sp.) is a widespread tree in Eurasia, represented by two species; F. sylvatica in Europe and F. orientalis in eastern Europe and Asia. Both species appear in the Rodopi mountains, in southeast Balkans. Five beech populations were sampled in the southern slopes of Rodopi along a west–east gradient representing an established transitional zone between the two beech species. The diversity of six leaf traits was examined in shade leaves and leaves exposed to direct irradiation. Significant differences appeared among populations and among the two shading classes. Western beech populations consisted of trees with smaller leaves and fewer veins and were morphologically closer to F. sylvatica, while eastern populations seemed to be closer to F. orientalis. Shade leaves were constantly larger and less round than light leaves, probably due to different light harvesting strategies. The differences between populations were larger for shade leaves than for light leaves and presented a clear east–west trend, consistent to the differentiation pattern provided by previous genetic studies in the same region. Our results indicate that shade leaves probably maintain their size and shape independent from light irradiation and therefore may better express genetic differences among populations.

Studies comparing species’ distribution range at different time periods provide valuable information about temporal trends, and may help to identify the factors responsible for these changes. This knowledge is vital for setting conservation priorities and applying suitable management strategies and practices focused on species’ conservation. We examined records produced before and after December 31, 1985 for determining possible changes in the distribution range of 195 orchid species recorded in Greece, using a 10 × 10 km grid as the recording unit. We used regression techniques to explore the association of species richness with environmental and spatial variables. Species richness was calculated by using the orchid records made (a) before December 31, 1985, (b) after January 1, 1986, and (c) in both time periods. Generalized linear models (GLM) were used for identifying the most significant factors associated with the distribution of the threatened orchids of Greece. Most Greek orchids showed an increasing trend in distribution from the first to the second period, with the exception of a few Critically Endangered species, whose distribution was larger in the first than in the second period. The spatial distribution of the threatened orchids was mostly explained by land area and the area of the calcareous substrates at each grid cell, whereas all variables that were used in the GLM analysis accounted for about 32% of the variance. The observed increasing trend in orchid distribution should be attributed to the extensive research efforts during the second period, especially in areas of high altitude and towards the northern parts of Greece. Our results did not support the findings of other studies, mainly from northern Europe, which showed a significant decline in the distribution range of their orchid flora. These differences in distribution trends could be attributed to the complex orographic configuration of Greece, which renders large parts of the country rather unsuitable for agricultural use or for extensive urban development.

Hybridization is a process of great importance in the ecology and evolution of plants. However, identifying hybrids is not an easy task, especially in cases of sympatry. Such cases are the Abies taxa in Greece; Silver fir (A. alba), Greek fir (A. cephalonica) and King Boris fir (A. × borisii-regis). The latter has been characterized as a hybrid between the first two species as its morphological traits are either a combination of the parental ones or intermediate. Besides the morphological traits, A. × borisii-regis has so far been identified only at the population level, with biochemical and DNA markers. Here, we describe the identification of A. × borisii-regis at the individual level by employing a species-specific marker in the cpDNA and another in mtDNA, taking advantage of their uniparental inheritance mode from the paternal and the maternal parent, respectively. In addition, based on these markers, essential information emerges on the distribution and the mtDNA diversity of the Abies taxa in Greece.

The neglected and underutilized plants (NUPs) could become alternative food sources in the agro-alimentary sector, enriching human and animal diets, offering the opportunity for sustainable exploitation, resilience to climate change, and production with resistance to pests and diseases. In the Mediterranean countries, these valuable resources are threatened by climate change, overexploitation, and/or monoculture. In this framework, we evaluated 399 local endemic NUPs of Crete (Greece), the Mediterranean coast, Rif of Morocco, and Tunisia, regarding their agro-alimentary potential, and assessed their feasibility and readiness timescale for sustainable exploitation with own previously published methodology. The methodological scheme was developed by experts in co-creative workshops, using point-scoring of seven attributes to evaluate the potential of the targeted NUPs in the agro-alimentary. Our results showed a diversity of promising local endemic NUPs of different families in the studied regions (Lamiaceae members are prominent), and we outlined the cases of 13 taxa with the highest optimum scores of agro-alimentary potential (&gt, 70%). Despite the diversity or the promising potential and current ex-situ conservation efforts to bridge gaps, our study indicated that only a few cases of Cretan local endemic NUPs can be sustainably exploited in the short-term. However, it is argued that many more local endemic NUPs can easily follow sustainable exploitation schemes if specific research gaps are bridged. Since NUPs can help to increased diversification of food production systems by adding new nutritional/beneficial species to human and animal diets, basic and applied research, as well as market and stakeholder attraction, is suggested as prerequisite to unlock the full potential of the focal endemic NUPs in the agro-alimentary sector.

Patterns of phylogenetic diversity and structure of flora in refugial areas may be very complex due to habitat heterogeneity and legacies of various historical processes. Revealing these patterns can help understand the nature of the refugia. Here we study phylogenetic patterns of the flora in one of the main putative Pleistocene refugia of temperate forest biota in Europe through a community-level analysis for the main types of forests. For this purpose, a database of vegetation plots from deciduous and mountain coniferous forests of northern and central Greece was created. The plots were classified into floristically and ecologically interpretable community types. Faith’s phylogenetic diversity, mean phylogenetic distance and mean nearest taxon distance, as well as their standardized equivalents, were used to characterize the mean phylogenetic diversity and structure of each community type. All analyses were applied both for all the vascular plant taxa and for angiosperm taxa only. We related the measures of phylogenetic diversity and structure to ecological factors and compared them among community types. The 25 identified community types differed in their phylogenetic diversity and structure. The observed patterns were significantly different when old evolutionary lineages, such as gymnosperms and ferns, were taken into account. A random or overdispersed phylogenetic structure was observed for most of the community types, while only two oak-dominated community types were clustered. The highest phylogenetic diversity and a notably high proportion of plots with an overdispersed phylogenetic structure were observed in two mesic ravine forest community types (one of these transitional to beech forests). Phylogenetic metrics correlated with ecological conditions, in particular, overdispersion was more common in shaded, cool and moist forests. The high phylogenetic diversity and overdispersed structure of the two ravine community types can be related to the putative refugial role of these forest habitats.

Neottia cordata is an orchid species that exclusively occurs in Picea abies subsp. abies and Pinus sylvestris stands and forms its southernmost distribution limits in Greece. Over the last decade, it has been recorded in numerous sites, in which it forms small colonies, both in terms of population and area. This research re-evaluates the threat status of Neottia cordata based on updated chorological and population data; it also checks the effectiveness of the Natura 2000 Network as far as its conservation is concerned by applying the MaxEnt model. The recently collected data justify the classification of N. cordata as "Vulnerable". The most significant variables that affect its distribution were found to be the vegetation type and the precipitation of the warmest quarter. The results of the MaxEnt model suggest that: (i) the Natura 2000 Network is characterised by areas of higher habitat suitability values when compared to the areas that fall outside this network; and, (ii) Picea abies subsp. abies forests are more suitable for its conservation than those of Pinus sylvestris. It is concluded that the most appropriate management measure for the species conservation is the maintenance of the tree layer canopy closed.

Understanding the variation in community composition and species abundances, i.e., β-diversity, is at the heart of community ecology. A common approach to examine β-diversity is to evaluate directional turnover in community composition by measuring the decay in the similarity among pairs of communities along spatial or environmental distances. We provide the first global synthesis of taxonomic and functional distance decay along spatial and environmental distance by analysing 149 datasets comprising different types of organisms and environments. We modelled an exponential distance decay for each dataset using generalized linear models and extracted r2 and slope to analyse the strength and the rate of the decay. We studied whether taxonomic or functional similarity has stronger decay across the spatial and environmental distances. We also unveiled the factors driving the rate of decay across the datasets, including latitude, spatial extent, realm, and organismal features. Taxonomic distance decay was stronger along spatial and environmental distances compared with functional distance decay. The rate of taxonomic spatial distance decay was the fastest in the datasets from mid-latitudes while the rate of functional decay increased with latitude. Overall, datasets covering larger spatial extents showed a lower rate of decay along spatial distances but a higher rate of decay along environmental distances. Marine ecosystems had the slowest rate of decay. This synthesis is an important step towards a more holistic understanding of patterns and drivers of taxonomic and functional β-diversity.

Land abandonment in European mountains threatens habitats shaped for centuries by low-intensity agriculture and grazing. Hence, it is important to identify spatiotemporal patterns in rural abandonment, and relate them to biophysical and socioeconomic drivers. We pursued these goals in the theoretical context of transitions from traditional to productivist and then to post-productivist agriculture. We conducted a case study in a representative of southern Europe sub-mountainous marginal area that was once traditionally exploited (Pindus range, Epirus, Greece). Land cover was mapped from the outset of abandonment (years 1945, 1970, 1996 and 2015), and we subsequently calculated landscape metrics. An Intensity Analysis facilitated the comparison of rates of land cover change between time periods. By employing random forest modelling, we related socioeconomic, physiographic, geological and climatic predictors to land type occurrence and succession intensity. We found that farmland decreased from 30% to 3% during the 70 years of the study period, and that forest increased from 22% to 63%. The landscape’s heterogeneity, ecotone diversity, and spatial aggregation decreased. Abandonment and succession accelerated and relocated to lower elevation, especially during the latest time period, which was related to a second depopulation wave and livestock decrease. The remaining lowland farmlands were of productivist agriculture, and no widespread post-productivist regime was found. Thus, our study supports the view that policies, which have been mainly based on the linear transition of agricultural regimes in northern Europe, must take into account southern European mountains, where widespread abandonment can coexist with limited intensification and extensification.

Monitoring of habitat types conservation status is an essential task in the frame of the European policy for biodiversity conservation. The parameters to be assessed for the purposes of habitat types’ conservation status assessment are described in several European documents, but the methodology for their determination has not yet been standardized or optimized. This study presents methods for the assessment of the actual status and the future prospects of structure and functions of habitat types. Specifically, it presents a bottom–up approach for the assessment of these two parameters at different spatial scales. In the proposed method, conservation status assessment is based on a classification of habitat types to subtypes, with the latter representing the basic monitoring entities. The conservation status is assessed by recording: (i) the presence/absence of specific indicators of structure and functions per habitat type, and (ii) the presence/absence, abundance, and vitality of the typical species of the habitat subtypes. The typical species are determined objectively using algorithms and fidelity coefficient values. The conservation status and future prospects of structure and functions (including the typical species) are estimated quantitatively with the help of numerical methods and algorithms, but their assignment to conservation status classes is based on thresholds defined by experts. Assessments are made at the local scale, but can be upscaled to coarser ones (up to the national level). The proposed methods have been applied in Greece and were effective both in terms of results obtained and costs needed.

The goal of this study was to quantitatively assess the relationship linking vegetation and airborne pollen. For this, we established six sampling stations in the city of Thessaloniki, Greece. Once every week for 2 years, we recorded airborne pollen in them, at breast height, by use of a portable volumetric sampler. We also made a detailed analysis of the vegetation in each station by counting all existing individuals of the woody species contributing pollen to the air, in five zones of increasing size, from 4 to 40 ha. We found the local vegetation to be the driver of the spatial variation of pollen in the air of the city. Even at very neighbouring stations, only 500 m apart, considerable differences in vegetation composition were expressed in the pollen spectrum. We modelled the pollen concentration of each pollen taxon as a function of the abundance of the woody species corresponding to that taxon by use of a Generalized Linear Model. The relationship was significant for the five most abundantly represented taxa in the pollen spectrum of the city. It is estimated that every additional individual of Cupressaceae, Pinaceae, Platanus, Ulmus and Olea increases pollen in the air by approximately 0.7, 0.2, 2, 6 and 5%, respectively. Whether the relationships detected for the above pollen taxa hold outside the domain for which we have data, as well as under different environmental conditions and/or with different assemblages of species representing them are issues to be explored in the future.

We studied the differentiation among plant communities of deciduous broadleaved and mountain coniferous forests in terms of functional diversity and identity at a regional scale (northern and central Greece). We asked if patterns of functional differentiation among communities are consistent between the overstorey and understorey layers and if they can be influenced by deep past environmental conditions. Functional Richness (FRic) and Functional Dispersion (FDis), as well as their standardized effect sizes, were employed to assess the multivariate functional diversity of the community types. In contrast, single-trait Community Weighted Means (CWMs) were used as surrogates of functional identity. The aforementioned indices were calculated for three datasets, namely all the vascular plant taxa found in individual vegetation plots (total community), all phanerophyte (tree and shrub) taxa (overstorey) and all non-phanerophyte vascular plant taxa (understorey). We found that community types and especially four broad forest types (beech, ravine, pine and oak forests) are well differentiated in terms of functional composition (identity), as indicated by Non-Metric Multidimensional Scaling (NMDS). After conducting an NMDS for the three datasets, functional identity based on the total floristic composition was found to be the best discriminator of the studied communities. However, contrasting patterns were found for some specific traits or their categories between overstorey and understorey layers. The patterns of functional diversity of the community types (based on multivariate indices), revealed by calculating the standardized effect sizes of FRic and FDis based on the richness null model, did not differ substantially from random expectations for most of the studied community types when the dataset of all the vascular plant taxa was analyzed. However, the patterns revealed for the overstorey layer differed from those for the understorey layer. For the latter layer, the clustered structure was revealed in many community types based on the ses.FDis metric. Indications of deep past influence on the functional composition were found for certain community types (i.e. ravine forests) based on single-trait metrics, but no indication of such influence was found based on multivariate indices. Our findings highlight the complementarity and the additive explanatory value of the simultaneous use of single- and multi-trait approaches and their application to different layers in forests.

The ability of beech (Fagus sylvatica L.) populations to adapt to the ongoing climate change is crucial for the maintenance of economic and social benefits and for the conservation of biodiversity in Europe and especially in the southeastern part of the continent, where environmental change is expected to be more intense. Beech populations in the region cover multiple ecological conditions at a small geographical range and have a complex biogeographical background involving several postglacial lineages originating from distant or local refugia. In this study, we tested the existing adaptive potential of eight beech populations from two provenances in N.E. Greece (Evros and Drama), under simulated controlled climate change conditions in a growth chamber and in the field. In the growth chamber, simulated conditions of temperature and precipitation for the year 2050 were applied for three years, under two different irrigation schemes, a non-frequent (A1) and a frequent one (A2). Seedling survival, growth and leaf phenological traits were used as adaptive traits. The results showed that beech seedlings were generally able to survive under climate change conditions and showed adaptive differences among provenances and populations. Furthermore, beech genotypes demonstrated an impressive phenotypic plasticity by changing the duration of their growing season allowing them to avoid environmental stress and high selection pressure. Different populations and provenances were connected with different adaptation strategies, that relate mainly to the temporal distribution patterns of precipitation and temperature, rather than the average annual or monthly values of these measures. Additionally, different adaptive strategies appeared among beech seedlings when the same amount of water was distributed differently within each month. This indicates that the physiological response mechanisms of beech individuals are very complex and depend on several interacting parameters. For this reason, the choice of beech provenances for translocation and use in afforestation or reforestation projects should consider the small scale ecotypic diversity of the species and view multiple environmental and climatic parameters in connection to each other.

[EN] Sixty modern surface samples collected from mosses in different cypress forest communities (Cupressus sempervirens L.) on the island of Crete (Greece) were analysed for their pollen content. The samples were taken from six different cypress phytosociological associations between 23 and 1600 m asl, and fall within distinct rainfall and temperature regimes. The aims of this paper are to provide new data on the modern pollen rain from the Aegean islands, and to perform these data using multivariate statistics (hierarchical cluster analysis and canonical correspondence analysis) and pollen percentages. The discrimination of pollen assemblages corresponds to a large extent to the floristic differentiation of Cupressus sempervirens forest vegetation and indicates the existence of three new associations, [ES] Sesenta muestras de lluvia polínica actual recolectadas en cepellones de musgos, procedentes de distintas comunidades de ciprés (Cupressus sempervirens L.) en la isla de Creta (Grecia), fueron analizadas palinológicamente. Las muestras proceden de seis asociaciones fitosociológicas dominadas por el ciprés entre 23 y 1600 m asl, bajo regímenes de precipitación y temperatura diferentes. El objetivo de este trabajo es prover datos novedosos acerca de la lluvia polínica actual en las islas del Egeo, así como tratar éstos mediante análisis multivariantes (análisis de cluster jerárquico y análisis de correspondencias canónicas) y a partir de sus porcentajes polínicos. La discriminación de los espectros polínicos corresponde en gran medida a la diferenciación florística de la vegetación de los bosques de Cupressus sempervirens e indica la existencia de tres nuevas asociaciones, This study is part of the international PALEOMEX-INEE Research Program, itself a component of the Mediterranean Integrated Studies at Regional and Local Scales (MISTRALS) of the CNRS, France.

Flowering and pollen seasons are sensitive to environmental variability and are considered climate change indicators. However, it has not been concluded to what extent flowering phenology is indeed reflected in airborne pollen season locally. The aim of this study was to investigate, for a wide spectrum of plant species, the responsiveness of flowering to different environmental regimes and also to check for commensurate changes in the respective pollen seasons. Fourteen taxa were selected representing the families of Corylaceae, Cupressaceae, Fagaceae, Oleaceae, Pinaceae and Platanaceae. Each was studied for at least one full flowering year and in at least two sampling stations differing in elevation or direction within the period 2004–2011. Flowering observations were made 2–3 times a week, from flower differentiation to flower desiccation; >1000 daily observations were made in 225 plant individuals, in total. Data were regressed against meteorological parameters in an attempt to identify the driving factors of flowering onset and offset. Flowering dates were compared with dates of the related airborne pollen seasons per taxon; airborne pollen monitoring took place daily using a Hirst-type volumetric sampler. For all taxa, flowering started earlier at lower elevations or southern direction. Cumulative temperature proved to be the factor most significantly affecting flowering onset and end for all species (p 0.70). For the majority of the taxa examined, airborne pollen season did not coincide locally with the respective flowering periods of the selected species: flowering could precede pollen season, even for more than one month (as in C. avellana), or start after the pollen season onset (as in P. brutia). The strong sensitivity of flowering to air temperature is not the case in the respective pollen seasons. This raises questions on the relationship between flowering times and airborne pollen seasons and on the rather underestimated role of long-distance transport of pollen.

This study presents a first, national scale approach on ecosystem condition assessment for Greece, through integrating the available surveillance and monitoring data for habitat types, at the plot level, within the Natura 2000 network. The study consists of two parts: (a) ecosystem condition assessment for ecosystem types in Greece, using the conservation degree at plot level as an indicator and (b) a large scale analysis of the forest types' condition using, as indicators, the pressures and typical plant Typical species richness, as an exemplary case to interpret the outcomes of the assessment. The main results of this study revealed that: (i) the majority of the ecosystem types are in above good condition, with the higher percentages of bad condition recorded for wetlands, rivers and lakes, marine inlets and transitional waters, (ii) forest categories in their majority are at above-adequate condition, (iii) at forest ecosystem categories specific pressures (e.g. grazing, cultivations, forestry clearance) act as main drivers forecosystem condition change, (iv) Mediterranean deciduous forests are the most floristic-rich forest category, regarding typical plant Typical species. Simultaneously, it is highlighted that already available datasets could be used for immediate and rapid framework assessments, which will guide future steps on ES studies, research and decision-making.

The Water Framework Directive (WFD) requires Member States to develop appropriate assessment methods for the classification of the ecological status of their surface waters. Mediterranean region has lagged behind in this task, so we propose here the first developed method for Greek lakes, Hellenic Lake Macrophyte (HeLM) assessment method. This method is based on two metrics, a modified trophic index and maximum colonization depth Cmax that quantify the degree of changes in lake macrophytic vegetation, as a response to eutrophication and general degradation pressures. The method was developed on the basis of a data set sampled from 272 monitoring transects in 16 Greek lakes. Sites from three lakes were selected as potential reference sites by using a screening process. Ecological quality ratios were calculated for each metric and for each lake, and ecological status class boundaries were defined. For the evaluation of effectiveness of the method, the correlations between individual metrics and final HeLM values and common pressure indicators, such as total phosphorus, chlorophyll a and Secchi depth, were tested and found highly significant and relatively strong. In addition, the ability of HeLM values and its individual metrics to distinguish between different macrophytic communities’ structure was checked using aquatic plant life-forms and found satisfactory. The HeLM method gave a reliable assessment of the macrophytic vegetation’s condition in Greek lakes and may constitute a useful tool for the classification of ecological status of other Mediterranean lakes. Electronic supplementary material The online version of this article (10.1007/s10661-018-6708-1) contains supplementary material, which is available to authorized users.

Aim: Formalized classifications synthesizing vegetation data at the continental scale are being attempted only now, although they are of key importance for nature conservation planning. Therefore, we aim to provide a vegetation classification and to describe the main biogeographical patterns of floodplain forests and alder carrs in Europe. Location: Europe. Methods: A database of more than 40 000 vegetation plots of floodplain forests and alder carrs across Europe was compiled. After geographic stratification, 16 392 plots were available for classification, which was performed using the supervised method Cocktail. We also searched for new associations using semi-supervised K-means classification. The main biogeographic patterns and climate-related gradients in species composition were determined using detrended correspondence analysis and cluster analysis. Results: Thirty associations of floodplain forests and alder carrs were distinguished, which belong to five alliances. The Alnion incanae includes riparian, seepage and hardwood floodplain forests in the nemoral and hemiboreal zones (dominated by Alnus glutinosa and Fraxinus excelsior) and in the boreal zone (dominated by A. incana). The Osmundo-Alnion represents oceanic vegetation dominated by Alnus glutinosa, Fraxinus angustifolia and F. excelsior distributed mostly on the Iberian Peninsula and composed of species with Atlantic distribution and Iberian endemics. The Populion albae comprises floodplain forests frequently dominated by Fraxinus angustifolia, Populus alba and P. nigra that are widespread in floodplains of large rivers under summer-dry climates in the Mediterranean region. The Platanion orientalis represents eastern Mediterranean floodplain forests dominated by Platanus orientalis. The Alnion glutinosae includes forest swamps dominated by Alnus glutinosa distributed mostly in the nemoral and hemiboreal zones. The main biogeographic patterns within European floodplain forests and alder carrs reflect the climatic contrasts between the Mediterranean, nemoral, boreal and mountain regions. Oceanic floodplain forests differ from those in the rest of Europe. The hydrological regime appears to be the most important factor influencing species composition within regions. Conclusions: This study is the first applying a formalized classification at the association level for a broad vegetation type at the continental scale. The proposed classification provides the scientific basis for the necessary improvement of the habitat classification systems used in European nature conservation.

Premise of research. Even though the Balkan Peninsula is a biodiversity hot spot in southeastern Europe harboring many endemic plants, very little is known about the temporal extent of the phylogeographic history and the contemporary genetic diversity of the endemics there. Haberlea rhodopensis is one of the European Gesneriaceae species occurring in this region and represents appropriate study material to address these questions.Methodology. We generated fossil-dated molecular phylogenies (atpB-rbcL, trnH-psbA, trnLF, ITS) across the Lamiales to determine the origin and age of H. rhodopensis and conducted phylogeographic (trnH-psbA, ITS) and population genetic (ISSRs) analyses on 17 populations from Bulgaria and Greece, covering the entire distribution range of the species, to investigate their biogeographic history, present-day genetic diversity, and differentiation levels.Pivotal results. The European Gesneriaceae genera have a Tertiary origin in the early Oligocene, while the Haberlea lineage emerged ...

Questions Do the mechanisms driving community assembly differ between two islands of different age and history of vegetation development? How does sampling scale affect the strength that each assembly mechanism poses on the assembly of plant communities? Location Volcanic islands (Palea Kameni and Nea Kameni) of Santorini Archipelago, Greece. Methods Functional diversity has been proposed as a framework for discriminating among mechanisms of community assembly, such as habitat filtering, limiting similarity and random assembly. We investigated four plant communities in two sea-born volcanic islands. We recorded plant diversity at scales from 1 m2 to 64 m2. We calculated three indices of functional diversity: functional richness, functional evenness and functional divergence, using 26 functional traits (including vegetative characteristics, ecological preferences and regenerative characteristics). We used null model analysis to test for two different assembly mechanisms: habitat filtering and limiting similarity or random assembly. Results The assemblage of the four communities was complex and did not follow a single mechanism. In most cases, finer-scale patterns indicated randomness, while coarser scales revealed more structured communities. In the older island, the scrub community was mainly defined by limiting similarity. The therophytic community displayed a limited range of functional traits, indicating mainly habitat filtering, but within this range, the evenness of the distribution indicated limiting similarity. On the younger island, the range of traits did not differ from random. However, within this range of traits, one therophytic community showed signs of limiting similarity, while the second therophytic community displayed uneven functional trait distribution, indicating mainly habitat filtering. The three indices reflected different facets of functional diversity and were not correlated, thus we may argue that they are not redundant, and we even detected different mechanisms of assembly within the same community. Conclusions The functional diversity of the therophytic communities in the younger island implied no specific assembly mechanism; perhaps due to its age, the community is still at the early stages of colonization (i.e. stochastic processes, such as arrival of new species, prevail). In the older island, the lack of disturbances for a long period allowed the establishment of communities assembled by specific mechanisms, such as competition and habitat filtering.

QuestionsWhat are the main floristic patterns in European beech forests? Which classification at the alliance and suballiance level is the most convincing?LocationEurope and Asia Minor.MethodsWe applied a TWINSPAN classification to a data set of 24605 releves covering the whole range of Fagus sylvatica forests and the western part of Fagus orientalis forests. We identified 24 operational phytosociological units' (OPUs), which were used for further analysis. The position of each OPU along the soil pH and temperature gradient was evaluated using Ellenberg Indicator Values. Fidelity of species to OPUs was calculated using the phi coefficient and constancy ratio. We compared alternative alliance concepts, corresponding to groups of OPUs, in terms of number and frequency of diagnostic species. We also established formal definitions for the various alliance concepts based on comparison of the total cover of the diagnostic species groups, and evaluated alternative geographical subdivisions of beech forests.ResultsThe first and second division levels of TWINSPAN followed the temperature and soil pH gradients, while lower divisions were mainly geographical. We grouped the 22 OPUs of Fagus sylvatica forests into acidophytic, meso-basiphytic and thermo-basiphytic beech forests, and separated two OPUs of F.orientalis forests. However, a solution with only two ecologically defined alliances of F.sylvatica forests (acidophytic vs basiphytic) was clearly superior with regard to number and frequency of diagnostic species. In contrast, when comparing groupings with three to six geographical alliances of basiphytic beech forests, respectively, we did not find a strongly superior solution.ConclusionsWe propose to classify F.sylvatica forests into 15 suballiances - three acidophytic and 12 basiphytic ones. Separating these two groups at alliance or order level was clearly supported by our results. Concerning the grouping of the 12 basiphytic suballiances into ecological or geographical alliances, as advocated by many authors, we failed to find an optimal solution. Therefore, we propose a multi-dimensional classification of basiphytic beech forests, including both ecological and geographical groups as equally valid concepts which may be used alternatively depending on the purpose and context of the classification.

In this research paper the natural establishment of plants and their contribution to the reclamation of sewage sludge deposits through their uptake of nutrients and their bioconcentration factor (BCF) were investigated and assessed. The main research started in March 2012, and the plants growing naturally at the site under investigation during the first growing season (June 2012) were identified and recorded. On the basis of their occurrence and cover samples from ten species, namely Amaranthus albus L., Amaranthus viridis L., Cardaria draba (L.) Desv., Chenopodium album L., Cynodon dactylon (L.) Pers., Cyperus rotundus L., Lolium perenne L., Lycopersicon esculentum Mill., Malva parviflora L., Portulaca oleracea L., were collected for chemical analyses. Macronutrients (Ca, Mg, K, P), trace elements (Mn, Cu, Zn, Fe, Cr, Ni, Pb) and Na were measured. The results showed that plants took up macronutrients at relatively high rates, in some cases reducing their excessive levels of concentration in the sludge by as much as 95%. Trace elements were removed at a lower rate compared to hyperaccumulators, this was possibly affected by their reduced bioavailability in the substrate, but the BCF, which was greater than one for most of the species and for most of the trace elements, indicated that the plants were capable of phytoextraction. It was concluded that selected native plants are not only tolerant to adverse environmental conditions, but also contribute by various processes to the reclamation of sites affected by sewage sludge.

The present paper describes the floristic composition and synecology of steppe-like dry grasslands occurring in a Natura 2000 site in North-Central Greece around the two karstic lakes of Vegoritida and Petron. In total, 245 relevés of vascular plant species composition and abundance were sampled and subjected to cluster analysis and ordination analysis. Passive explanatory variables, including environmental parameters as well as indicator values, were used to support the ecological interpretation. Four plant communities were distinguished in the area, namely Artemisia campestris-Dasypyrum villosum, Chrysopogon gryllus-Bothriochloa ischaemum, Satureja montana-Artemisia alba and Stipa capillata-Koeleria macrantha. All communities were classified within the Festuco-Brometea class and the Astragalo-Potentilletalia order. Soil properties (soil reaction, moisture and nutrient content) and meso-climate factors (temperature variation along topographic gradients) were identified as the main factors determining the floristic differentiation among the four communities. The dry grasslands harbor a number of species associated with steppic habitats. We discuss the relict character of the steppe-like vegetation. V članku opisujemo floristično sestavo in sinekologijo stepi podobnih suhih travišč, ki se pojavljajo v Natura 2000 območju v severni centralni Grčiji okoli dveh kraških jezer Vegoritida in Petron. Vzorčili smo 245 vegetacijskih popisov in jih analizirali s klastrsko in ordinacijsko analizo. Rastišče smo interpretirali s pasivnimi pojasnjevalnimi spremenljivkami, kamor smo vključili okoljske spremenljivke in indikatorske vrednosti. Na raziskovanem območju smo ločili štiri rastlinske združbe: Artemisia campestris-Dasypyrum villosum, Chrysopogon gryllus-Bothriochloa ischaemum, Satureja montana-Artemisia alba in Stipa capillata-Koeleria macrantha. Vse združbe smo uvrstili v razred Festuco-Brometea in red Astragalo-Potentilletalia. Lastnosti tal (reakcija tal) in mezo klimatski dejavniki (spreminjanje temperature vzdolž topografskih gradientov) so glavni dejavniki, ki vplivajo na floristične razlike med štirimi rastlinskimi združbami. V suhih traviščih najdemo številne vrste stepskih habitatov. V članku razpravljamo o reliktnem značaju stepi podobne vegetacije. peerReviewed

Broad-scale plastid (chloroplast) DNA studies of beech (Fagus sylvatica) populations suggest the existence of glacial refugia and introgression zones in south-eastern Europe. We choose a possible r ...

Modern water resource management requires biomonitoring of the structure and functioning of freshwater ecosystems, which may be better illuminated by functional trait distribution patterns and responses across human-induced pressure gradients. In this study, we applied the RLQ, the fourth-corner and their novel combination methods, in order to assess the relationship between the distribution of 30 aquatic macrophyte functional traits and 14 indicators of anthropogenic pressures across 16 freshwater lakes. Our findings showed that there is a statistically significant relationship between the distribution of specific functional traits and anthropogenic pressures. Eutrophication was the dominant pressure and the shift from a submerged-macrophyte dominated vegetation community to an emergent one was the most important functional response. Aerial reproduction and dispersal traits were found to replace water-related ones under higher nutrient concentrations. Trophic and light preferences of macrophytic species increased, while their leaf morphology was found to change from tubular/capillary leaf types with low leaf area values to entire leaf types with greater leaf area. These results provide hints on the changes in ecosystem functioning occurring as a response to human-induced drivers. Therefore, this assessment approach could provide important support to the tasks of biomonitoring, conservation and management planning in freshwater ecosystems.

We studied airborne pollen along an elevation gradient of Mt Olympos (Greece). Samples were collected on a regular basis, over the period March–October 2009, in eight elevation-different stations, by use of a portable Hirst-type volumetric sampler. Concurrently, we studied pollen production in Quercus coccifera, Q. ilex, Pinus heldreichii and P. nigra, which are dominant species in the main vegetation types of the mountain. Of the 35 pollen taxa detected in the air, 18 account for 99.1 % of the total airborne pollen. These are the main pollen taxa each contributing by at least 0.5 %. Pinaceae (32 %) followed by Quercus (24 %) and Urticaceae (18 %) are the most abundantly represented taxa. Duration of the pollen season decreases with elevation by on average 3 days for every 100 m of elevation increase or by 5 days for every Celsius-degree of temperature decrease. Pollen concentration in the air decreases with elevation for the lowland taxa; with the exception of Cupressaceae, no pattern is observed for the other main taxa. The pine and oak species studied carry comparable amounts of pollen, approximately 104 grains per flower, 108–109 per m2 of crown surface and 1010–1011 per individual; pollen production, primarily of the two Quercus species, is not responsive to environmental changes associated with elevation. Results provide evidence that, within a margin of error, airborne pollen reflects the distributions of pollen taxa on the mountain; regarding abundance, airborne pollen is representative of Quercus, but under-representative of Pinaceae. Ambrosia pollen is found at all elevations examined, although plants producing it have not been recorded on or around Mt Olympos.

Species distribution models are widely applied for generating the appropriate data for designing networks of reserve systems. The aim of the present study is to compare the use of presence/absence and continuous suitability data, derived from species distribution models, in reserve selection, and to detect any systematic trends in the reserve networks produced on the basis of these two types of data. The MAXENT model was applied to predict orchids’ potential distribution in east Macedonia (northeast Greece). One presence/absence and one with suitability values data set was made and used in the ZONATION decision support tool in order to prioritize the cells of the study area for inclusion in a reserve network. In the selection procedure, species weighting has been applied by using the species specialization index. Results show that the presence/absence data set favors the selection of cells with more extreme climatic conditions and more distant from the mean habitat of the study area. Furthermore, the continuous suitability data set provides higher suitability values for the specialist taxa in comparison with the presence/absence data set, while the opposite is happening for the generalist taxa. The present study reveals that the suitability data outperform the presence/absence data in reserve selection because: (a) they better represent the average environmental conditions of the study area in the selected networks; (b) they ensure higher suitability values for the specialist species, which are more prone to extinction in the future; and (c) they take full advantage of species weighting according to their habitat specificity.

Goodyera repens, a species of central and northern Europe, forms large populations in the Scotch pine forests in some areas of Mt Rhodopi (NE Greece), while it is completely absent in other areas with the same habitat type. The present study aims to investigate the ecological factors that constitute a barrier in the distribution of G. repens in its southernmost distribution limit. Data from 65 localities were sampled and chemical soil parameters were measured. Using the WorldClim database, the summer maximum temperatures and precipitation values were extracted. Binary logistic regression was used to determine the variables that best explain the distribution of G. repens. The data have been found to fit the model in a significant manner, and the independent variables significantly explaining the probability of G. repens being present were phosphorus, copper, and zinc. The results indicate that the distribution of G. repens is indirectly affected by soil variables through the establishment of mycor...

The woodland vegetation of Central Albania is studied and discussed along an altitudinal gradient in the Dajti National Park (DNP). The plant species combinations recorded in 168 plots were classified and subjected to indirect gradient analysis using environmental variables of geology, soil, topography, disturbance and grazing impact. The transect over more than 1300 m reflects the biogeographically intermediate paramediterranean vegetation zonation and the relatively humid Mediterranean “hygric series” at its eastern margins. It reveals the total range of woodland types known to occur in Central Albania, thus stressing the representativity of the area regarding biodiversity and biogeography, and its importance for nature conservation. Along the elevation gradient, we found three plant communities of the mesomediterranean Quercetalia ilicis, five of the supramediterranean Quercetalia pubescentis and five of the montane or oromediterranean Fagetalia sylvaticae.

In this study, we investigated the relationship between vegetation and modern-pollen rain along the elevational gradient of Mount Paggeo. We apply multivariate data analysis to assess the relationship between vegetation and modern-pollen rain and quantify the representativeness of forest zones. This study represents the first statistical analysis of pollen-vegetation relationship along an elevational gradient in Greece. Hence, this paper improves confidence in interpretation of palynological records from north-eastern Greece and may refine past climate reconstructions for a more accurate comparison of data and modelling. Numerical classification and ordination were performed on pollen data to assess differences among plant communities that beech (Fagus sylvatica) dominates or co-dominates. The results show a strong relationship between altitude, arboreal cover, human impact and variations in pollen and nonpollen palynomorph taxa percentages.

Biurrun, Idoia/0000-0002-1454-0433; Rojo, Maria Pilar Rodriguez/0000-0001-5449-9386; Ermakov, Nikolai/0000-0001-7550-990X; De Sanctis, Michele/0000-0002-7280-6199; Svenning, Jens-Christian/0000-0002-3415-0862; Virtanen, Risto/0000-0002-8295-8217; Agrillo, Emiliano/0000-0003-2346-8346; Onyshchenko, Viktor/0000-0001-9079-7241; Marceno, Corrado/0000-0003-4361-5200; Willner, Wolfgang/0000-0003-1591-8386; Fernandez-Gonzalez, Federico/0000-0003-1234-4065; Jansen, Florian/0000-0002-0331-5185; Swacha, Grzegorz/0000-0002-6380-2954; Dengler, Jurgen/0000-0003-3221-660X; Guarino, Riccardo/0000-0003-0106-9416; Sopotlieva, Desislava/0000-0002-9281-7039; Venanzoni, Roberto/0000-0002-7768-0468; Chytry, Milan/0000-0002-8122-3075; Kuzemko, Anna/0000-0002-9425-2756; Danihelka, Jiri/0000-0002-2640-7867; Kuzemko, Anna/0000-0002-9425-2756; Venanzoni, Roberto/0000-0002-7768-0468; Gavilan, Rosario G./0000-0002-1022-445X; Jansen, Florian/0000-0002-0331-5185; Wohlgemuth, Thomas/0000-0002-4623-0894; Svenning, Jens-Christian/0000-0002-3415-0862; Sibik, Jozef/0000-0002-5949-862X; Casella, Laura/0000-0003-2550-3010; Lenoir, Jonathan/0000-0003-0638-9582; Attorre, Fabio/0000-0002-7744-2195; Kacki, Zygmunt/0000-0002-2241-1631; Jandt, Ute/0000-0002-3177-3669; Carni, Andraz/0000-0002-8909-4298; Jirousek, Martin/0000-0002-4293-478X; GARCIA-MIJANGOS, ITZIAR/0000-0002-6642-7782; Campos, Juan Antonio/0000-0001-5992-2753; Fanelli, Giuliano/0000-0002-3143-1212; Haveman, Rense/0000-0001-9127-4549; Acic, Svetlana/0000-0001-6553-3797; De Bie, Els/0000-0001-7679-743X; Font, Xavier/0000-0002-7253-8905; Moeslund, Jesper Erenskjold/0000-0001-8591-7149; Martynenko, Vasiliy/0000-0002-9071-3789; Jimenez-Alfaro, Borja/0000-0001-6601-9597; Ejrnaes, Rasmus/0000-0003-2538-8606; Carlon Ruiz, Luis/0000-0003-3442-8710; Angelini, Pierangela/0000-0002-5321-9757; Silc, Urban/0000-0002-3052-699X; Landucci, Flavia/0000-0002-6848-0384; Ewald, Jorg/0000-0002-2758-9324; Dziuba, Tetiana/0000-0001-8621-0890 WOS: 000368074600018 The European Vegetation Archive (EVA) is a centralized database of European vegetation plots developed by the IAVS Working Group European Vegetation Survey. It has been in development since 2012 and first made available for use in research projects in 2014. It stores copies of national and regional vegetation-plot databases on a single software platform. Data storage in EVA does not affect on-going independent development of the contributing databases, which remain the property of the data contributors. EVA uses a prototype of the database management software TURBOVEG 3 developed for joint management of multiple databases that use different species lists. This is facilitated by the SynBioSys Taxon Database, a system of taxon names and concepts used in the individual European databases and their corresponding names on a unified list of European flora. TURBOVEG 3 also includes procedures for handling data requests, selections and provisions according to the approved EVA Data Property and Governance Rules. By 30 June 2015, 61 databases from all European regions have joined EVA, contributing in total 1 027 376 vegetation plots, 82% of them with geographic coordinates, from 57 countries. EVA provides a unique data source for large-scale analyses of European vegetation diversity both for fundamental research and nature conservation applications. Updated information on EVA is available online at http://euroveg.org/eva-database. Czech Science Foundation (Centre of Excellence PLADIAS) [14-36079G] Our major thanks go to thousands of European vegetation scientists of several generations who collected the original vegetation-plot data in the field, published them or made their unpublished data available to others, and to those who spent myriad hours digitizing data and managing the contributing databases. EVA data management has been partly funded by the Czech Science Foundation (Centre of Excellence PLADIAS, 14-36079G).

An inventory of the endemic vascular plants of the Peloponnese (395 species and subspecies) has been created based on literature, herbarium and field data. Endemics’ distribution patterns, altitudinal distribution and habitat specificity were investigated. A rarity score for each endemic has been calculated based on its population size, geographic range and habitat specificity. The main mountainous areas of the Peloponnese are largely congruent to the hotspots of endemism. Altitudinal range and niche breadth of the endemics were positively correlated to their range size. The elevational gradient of the endemic species richness showed a hump-shaped pattern, in contrast to the monotonically decreasing pattern of total species richness. Endemic species were found to support boundary theory, while total species richness distribution followed the Rapoport’s elevational rule. The elevational distribution of the average rarity score and the average weighted threat of the endemics resulted in low values for mid-elevation intervals and increased values for low and high altitude areas, indicating that conservation efforts should focus on the two extremes of the elevational gradient. Area prioritization methods were applied using a rarity/complementarity based algorithm with two species weighting schemes. Their results were largely congruent confirming the significance of the main mountainous areas for the conservation of the endemics. Spatial overlap among selected grid cells using the rarity/complementarity analysis and Natura 2000 network was found to be low. Our results revealed the conservation importance of at least one new area located on Kythera Island.

This paper describes an integrated GIS-based methodology for conservation value assessment using the traditional species-based and a habitat-based multi-criteria evaluation. The methodology was applied to 49 small islands and islets in the East Aegean area, belonging to a SCI Natura 2000 site. The species-based (botanical approach) conservation status assessment attributes a specific weight to the parameter of endemism, while the multi-criteria evaluation (MCE) approach emphasises the criteria of diversity, rarity, naturalness, replaceability and threat on each habitat type in combination with the number of significant taxa. The conservation values attained from the two approaches are significantly correlated, but the multi-criteria approach is more effective as it includes all the habitat types within the study area in the 25% of the polygons with the highest conservation values. Furthermore, results from the multi-criteria analysis were more in line with subjective assessments of the conservation value of the habitat types than the ones obtained by the botanical approach.

Diversity in leaf morphological traits was assessed in 38 Greek Fagus sylvatica populations, covering the distribution of the species in the country. The relationship between the post-glacial origin of these populations and leaf morphology was investigated. The results showed a complex and geographically continuous morphological diversity pattern, influenced mainly by traits expressing leaf size, leaf shape and petiole length. Two simultaneous trends appeared to be responsible for the existing diversity pattern. One was geographical, with leaf types resembling F. sylvatica subsp. sylvatica occurring in the western part of the distribution of beech in Greece and types resembling F. sylvatica subsp. orientalis being dominant in the eastern part. A second trend seemed to be connected with the post-glacial origin of the populations, as described by previous plastid DNA haplotype studies of the same trees. The genetic background and the possible adaptation of beech populations to different environmental conditions have resulted in a complex morphological pattern, especially in areas in which different post-glacial lineages appear to meet. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165, 422–436.

Santorini (S Cyclades, Greece) is one of the active volcanoes of the South Aegean volcanic arc, with more than 12 major eruptions during the past 250,000 years. Our research, using a set of 93 phytosociological releves, focused on the two volcanic islands of Palea Kameni (PK) and Nea Kameni (NK), differing in age and history of vegetation development. Numerical classifi cation techniques were used to defi ne plant communities, and Redun- dancy Analysis (RDA) was used to investigate the main environmental gradients and identify the explanatory vari- ables with a unique signifi cant contribution to the explanation of the communities' fl oristic composition. In RDA environmental factors such as altitude, slope inclination, relief, aspect, age of geological substrate, distance from the shore, and selected Ellenberg Indicator Values (EIVs) were used. In order to test the robustness of the RDA results, principal components analysis was applied to the releves data set as well. Partial RDAs (variance partitioning) were also applied to investigated the proportion of variance attributed to the age of the lava substrate as compared to the rest of environmental factors. The classifi cation revealed seven plant communities (four on PK and three on NK), described in terms of unique species composition, characteristic ecology, and distribution. Three of the communities were dominated by perennials (all found on PK), while the other communities were built prevalently of therophytes (all communities found on NK and one occurring on PK). The age of lava substrate was found among the most important and statistically signifi cant variables. Furthermore, EIVs for light, nitrogen, reaction, and salinity were found to explain relatively high and statistically signifi cant proportions of species data variance. However, the pro- portion of variance attributed purely to the age of lava substrate was by far smaller than that attributed to the rest explanatory variables. Conclusively, we suggest that the formation of local pioneer vegetation on the studied volca- nic islands is not solely controlled by the age of the substrate ("maturation" of the communities through saturation of their local species pools), but it is also under strong control of factors such as the distribution of ashes after the recent volcanic eruptions, and the chemical and physical properties (e.g. nutrient content) of the soils formed by the deposition of the ashes.

Question: How can we determine differential taxa in a vegetation data set? Methods: The new algorithm presented here uses an intuitive fidelity threshold based on relative constancy differences. It is tested on a simulated and a real data set. The results of the proposed algorithm are discussed in comparison with other methods used for the determination of differential taxa.

SummaryPalynological analysis was carried out on 135 samples of Greek thyme honeys, selected from three experimental apiaries under controlled conditions. Samples of all plants in flower growing around the bee colonies were collected and a comparison of their pollen was made with pollen grains identified in the honeys. Pollen grains of Thymus capitatus were found in all honey samples with a content ranging from 27 to 95%, thus upgrading the designation of the Greek floral honey as thyme honey. A qualitative analysis revealed the presence in the honeys of pollen grains of 37 taxa belonging to 15 families. A quantitative analysis showed that the total number of pollen grains (NPG) in the honey samples had a considerable variation between areas with a mean value of 65,000 per 10 g of honey. As it appears to be influenced by many different factors, quantitative analysis cannot be used alone to identify the geographic origin of the honey. The geographical determination among the three studied areas was made po...

The establishment of a network of reserves is of fundamental importance to the loss of biodiversity. Seven different area selection methods for the establishment of a reserve network were applied in the present study: (a) 5% cut-off value of the grid cells with the highest species richness or conservation value, (b) complementarity analysis using as criteria species richness or conservation value or rarest species richness, and (c) mixed complementarity analysis using as criteria species richness or conservation value. These methods were applied in the orchid taxa of east Macedonia. The conservation values of taxa were estimated on the basis of regional rarity, broad-scale rarity, and species specialization. The spatial overlap between the resulting networks and the Natura 2000 network of the study area was assessed. Furthermore, the efficiency of the latter network to protect the orchid taxa of the study area was examined. Our results suggest that: (a) a multiscale estimation of rarity is necessary for the unbiased estimation of species conservation values; (b) species specialization adds valuable ecological information to the assessment of taxa conservation values; (c) complementarity and mixed complementarity analyses on species richness or conservation value safeguard all the taxa of the region; (d) complementarity analysis on the basis of the richness of the rarest species safeguards all the rarest taxa, but not the total number of the remaining taxa; (e) the 5% cut-off value on species richness or conservation value fails to protect all the taxa of the region, including a large number of the rarest taxa; and (f) the Natura 2000 network, despite its large coverage in the study area, fails to safeguard all the taxa, including some of the rarest.

The orchid family is one of the largest in the flowering plant kingdom and includes a lot of rare, threatened or endangered species. The determination of plant species niche is considered fundamental for their conservation. Two parameters closely related with species niche are niche marginality and breadth. The first parameter is a measure of how typical or atypical a species niche is within an area, while the second is a measure of species tolerance. This study deals with niche analysis of the orchids of east Macedonia (NE Greece). Factors that are known to determine species distribution on a regional scale, such as altitude, aspect, habitat type, bedrock type and soil properties (acidity, organic matter, and phosphorus content) were used as explanatory variables. Geographical coordinates were also employed in order to explore spatial patterns in orchid distribution. Niche analysis was carried out using the Outlying Mean Index (OMI) analysis. Out of the total data of 55 taxa that were analyzed, 41 had a significant marginal niche compared with the average niche of the study area. Altitude, soil acidity and certain habitat types were found to be the most important factors in determining orchid distribution. Five different species groups were distinguished on the basis of their ecological preferences and niche breadth. Species niche marginality and breadth, the amplitude of their geographical distribution, the size of their populations and the rareness and conservation status of their habitats were taken into account in order to set conservation priorities for the orchids in the study area. The above characteristics combined with intuitive criteria (e.g. geographical distribution, endemicity) for the species with a small number of occurrences could form a sound basis for setting conservation priorities.

Vasilopoulos G., Tsiripidis I. and Karagiannakidou V. 2007. Do abandoned tree plantations resemble natural riparian forests? A case study from northeast Greece. Bot. Helv. 117: 125– 142. The conversion of a riparian forest to plantations of fast-growing, exotic species (Populus × canadensis, Robinia pseudoacacia) may alter the floristic composition and soil properties, which may prevent the regeneration of natural forests when plantations are abandoned. Along the Nestos River in northeast Greece, we investigated how former plantations differ from natural forests after at least 14 years of abandonment. We carried out 60 vegetation releves and took soil samples in each plot to determine soil texture and chemical properties. Relationships between the forest type (natural vs. abandoned plantations), the floristic composition of the understory and soil properties were analysed with classification (TWINSPAN) and ordination (DCA). There was a clear floristic differentiation between natural forest and abandoned plantations, especially those of Robinia pseudoacacia. The topsoil of abandoned plantations had a lower content of organic matter and nitrogen, and the tree layer was still dominated by the formerly planted species. However, there was a similar floristic gradient, related mainly to soil texture (sandy vs. loamy sediments), in both the natural forest and abandoned plantations. Thus, even though the establishment of natural riparian forest species in the former plantations was scanty, their present floristic composition sufficiently reflects the natural ecological gradient to serve as a basis for a management plan to restore the natural riparian forest.

Pure and mixed beech forest vegetation of the southern Rodopi range (northeast Greece) was studied using 614 releves and multivariate analyses (TWINSPAN and DCA). Classification of the releves resulted in 12 vegetation units, 8 of which were ranked as associations or communities and the rest as subcommunities and variants. DCA diagrams of releves and taxa indicated that floristic differentiation was attributed mainly to factors such as altitude (affecting temperature and humidity), soil nutrient content and substrate type (affecting physical and chemical soil properties).

The recent taxonomic classification of beech in Europe considers existence of one species (Fagus sylvatica L.) with two subspecies: F. sylvatica ssp. sylvatica and F. sylvatica ssp. orientalis. Four beech populations growing on the Greek part of the Rodopi Mountains were studied using morphological traits as well as DNA molecular markers (AFLPs and chloroplast DNA SSR). The aim of the study was to describe the variation patterns of beech in the Rodopi Mountains and to test the hypothesis of possible introgression between the beech subspecies’ sylvatica and orientalis in this area. Both morphological traits and gene markers revealed a possible influence of F. orientalis on the east side of Rodopi and at the low elevations, while characters resembling F. sylvatica were observed mainly on the western part of the mountains and in higher altitudes. There was a clinal increase of genetic diversity from the west to the east, reaching a level firstly reported for beech populations. These results can be explained either by the existence of a main refugial area for beech during the last glaciation or by the occurrence of a recent hybridization among the subspecies, which were spatially isolated during the last glaciation and came into reproductive contact during their postglacial remigration. These two scenarios are not necessarily mutually exclusive.

Question: Which are the gradients of floristic differentiation in Greek beech (Fagu 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 phytosociological releves were used in the analyses. TWINSPAN and DCA were applied to classify and ordinate the releves. Altitude, Indicator Values of releves and their X and Y coordinates were used in a posteriori interpretation of the ordination axes. Kendall's correlation coefficients were calculated between DCA releve 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 reveale...

Tsiripidis, I. & Athanasiadis, N.: Contribution to the knowledge of the vascular flora of NE Greece: Floristic composition of the beech (Fagus sylvatica L.) forests in the Greek Rodopi. — Willdenowia 33: 273–297. — ISSN 0511-9618; © 2003 BGBM Berlin-Dahlem. The first Floristic inventory of the beech forests in the Greek Rodopi is presented. The investigation included pure beech (Fagus sylvatica L. s.l.) stands as well as mixed stands of beech with Pinus sylvestris, P. nigra, Picea abies, Abies ×borisii-regis, Quercus petraea subsp. medwediewii and Q. frainetto. The floristic catalogue is based on the floristic data of 584 phytosociological beech forests releves and on a supplementary floristic inventory. Published information of records from inside beech forests has also been taken into account. For each taxon information is given about its spatial and altitudinal distribution and constancy in the Greek Rodopi as well as about its ecological preferences. The floristic catalogue is divided in two ...

The Hellenic Natura 2000 Vegetation Database (GIVD ID EU-GR-005) was developed using TURBOVEG software package and currently comprises approximately 16,500 vegetation plots (releves), most of which (ca. 14,000) were sampled during the years 1999 and 2000. The remaining releves were derived from literature (period 1952 to 2000). Cover-abundance is given by the 7grade Braun-Blanquet scale for vascular plants. More than 90% of the plots are georeferenced and environmental data such as altitude, slope, aspect, geological substrate are given. All data refer to the Sites of Community Importance of the Natura 2000 network and all vegetation types of Greece that could be classified in the habitat types of the Dir. 92/43/EEC are represented. Vegetation and habitat maps of the sites are kept by the owner of the database. Quality control of releves is necessary before use. The significance and usefulness of the HelNatVeg database is high as it includes about 40% of releves ever sampled in Greece. Use of the database should be requested from the owner, the Hellenic Ministry of Environment, Energy and Climate Change.

Herbal medicinal products gain increasing popularity. The growing demand for herbal medicine along with a lack of regulation render herbal products subject to intentional adulteration. The substitution of costly ingredients with unlabelled plant-based fillers of inferior quality has been widely reported. Such fraudulent practices erode consumer trust, but can also pose serious health risks. In this work, 71 herbal medicinal products were randomly purchased from Greek markets and analysed using ITS2 metabarcoding for species identification. The aim was to investigate possible adulterations and assess the efficacy of metabarcoding in plant-based product authentication. Of the 131 detected species in our analyses, 87 were not listed on the product labels. This indicates a high level of adulteration and/or contamination during processing and distribution. Two toxic species, Chelidonium majus and Nicotiana tabacum, were also detected as major ingredients of two herbal mixtures for medicinal purposes. Furthermore, the detection of wheat in eight samples raises concerns for people with gluten intolerance. This study stresses the need for stricter quality control of herbal products. In addition, to overcome the limitations of metabarcoding and augment the approach we used Bar-HRM for the first time as a verification tool. The combination of metabarcoding with species-specific Bar-HRM analysisenhances the reliability of the results.