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A five-month survey on Eucalyptus spp., one of the most commonly planted trees in Cyprus, was undertaken in Limassol and Akrotiri in urban, rural and protected habitats. Two alien gall-inducing Eucalyptus wasps: Leptocybe invasa Fisher and La Salle, 2004 and Ophelimus maskelli (Ashmead, 1900) (Hymenoptera: Eulophidae) were recorded for the first time from Cyprus. In addition, three new alien parasitoids: Stethynium ophelimi (Huber, 2006) (Hymenoptera: Mymaridae), Closterocerus chamaeleon (Girault, 1922) (Hymenoptera: Eulophidae) and Megastigmus lawsoni Doğanlar and Hassan, 2010 (Hymenoptera: Torymidae), were reared from O. maskelli and L. invasa galls. The distribution, introduction and management actions for Eucalyptus spp. and their alien Chalcidoidea associates are discussed.

Key message Long Bosnian pine chronologies from different mountains are shaped by different climatic parameters and can help identify past drought events and reconstruct landscape histories. We developed a 735-year-long Pinus heldreichii chronology from the southern distribution limit of the species, expanding the available database of long Bosnian pine chronologies. Tree-ring growth was mainly positively correlated with growing degree days (GDD: r(1950-2018) = 0.476) while higher temperatures during both winter and growing season also enhanced growth (T-WT: r(1950-2018) = 0.361 and T-GS: 0.289, respectively). Annual precipitation, during both calendar and water years, had a negative but weaker impact on annual tree growth. The newly developed chronology correlates well with chronologies developed from the neighboring mountains. The years with ring width index (RWI) lower than the average were found to correspond to cool years with dry summers. Still, the newly developed chronology was able to capture severe drought events, such as those in 1660, 1687, and 1725. Several old living trees had internal scars presumably caused by fires. Therefore, old mature trees could be used for fire history reconstruction in addition to climate reconstruction. Although the presence of lightning scars indicates an important natural agent of fire ignition, human activities associated with animal grazing could also be an underlying reason for fires in the region., National Science Center

Invasive alien plant species represent an important threat to various protected areas of the world, and this threat expected to be further enhanced due to climate change. This is also the case for the most important network of protected areas in Europe, the Natura 2000 network. In the current study we evaluated the distribution pattern of alien plant taxa across selected continental and insular Natura 2000 sites in Greece and their potential spread 15 years since first being recorded in the field. A total of seventy-three naturalized plant taxa were recorded in the 159 sites under study. At the site level and regardless of the habitat group, the ratio of invaded areas increased between the two monitoring campaigns. An increase in the ratio of invaded plots was also detected for all habitat groups, except for grassland and riparian—wetland habitats. Precipitation during the dry quarter of the year was the factor that mainly controlled the occurrence and spread of alien plant taxa regardless of the site and habitat group. It is reasonable to say that the characterization of an area as protected may not be sufficient without having implemented the proper practices for halting biological invasions.

Mountain coniferous forests of Southern Europe seem to be increasingly affected by large fires. Endemic Greek fir (Abies cephalonica) forests were among the most affected ecosystems by the 2007 extreme wildfires in Greece. The aim of this study is to investigate the pattern of post-fire regeneration of fir forest plant communities of Mount Parnitha National Park, in Attica (Greece), after a large wildfire. A network of 8 severely burned sites across the mountain ridge was established in order to monitor natural regeneration of A. cephalonica as well as post-fire floristic composition and species richness. Field campaigns took place in two distinct time periods, one close to the fire event and one 8 to 10 years after. Generalized linear models were used to explore the effects of distance and microhabitat variables on the post-fire regeneration of the Greek fir. Distance from the unburned patches, slope and cover of woody species significantly affected A. cephalonica seedling establishment and hence its natural post-fire regeneration. Floristic composition and plant species richness of the recovering fir communities changed through time. During the initial phase, high species richness was recorded, mainly because of the high contribution of herbaceous species. During the second period, species richness was lower and similar to that recorded in the unburned fir communities. It is during this period when the first seedlings of the Greek fir managed to establish, although their density is rather low to ensure full recovery of the forest.

Pines are a major component of forests and other wooded lands in the Mediterranean region. Pine woodlands have increased during recent decades due to abandonment and afforestation. Fires are widespread throughout the region. Understanding the historical (Holocene) interactions between pines and fires is important for anticipating how ongoing climate change will affect future fires. Fire activity has increased during the Holocene alongside human activities, leading to the disappearance of many pinewoods. Fire frequency was low until the mid-twentieth century, when it began to increase, particularly in the southern European Union countries, reaching maximum values towards the late 1980s. Thereafter, the burnt area decreased despite regional warming, probably due to fire suppression policies and increased firefighting capacity. Pine woodlands are the second most burned vegetation after shrublands. Climate change will reduce the suitable habitat of primarily mountain pines. Rising emissions of greenhouse gases will increase the seasonal severity of fire weather, and, likely, the area burned. The extent of increase will depend on whether fires are limited by temperature or water. Extreme weather events are projected to increase in frequency and severity, meaning that despite growing firefighting capacity the potential for very large fires is very likely to continue increasing.

Pine forests represent a significant proportion of the vegetation of the Mediterranean Basin. Their abundance is explained in part by the importance they always have had for humans and the wide range of ecosystem services they provide. Pine forests and plantations are responsible for important provisioning services such as timber and firewood, but are rich in non-wood forest products, among which resin, pine nuts and edible mushrooms are the most outstanding examples. Of similar importance are the regulating services that pine woodlands provide. Erosion control and hydrological regulation have been the main reasons behind the establishment of many pine plantations throughout the Mediterranean Basin. Other regulating services of pine forests are their role in the carbon cycle, with pine stands representing a large fraction of carbon stocks in the Mediterranean region, and their importance as habitats for multiple, sometimes endangered, species. Pine forests also provide cultural services since pines are, esthetically, an iconic element in Mediterranean landscapes. Pine forests are enjoyed for multiple recreation and scientific activities. However, these ecosystem services are at risk of deterioration by several, and sometimes synergic, threats. Pine forests are very prone to fire, and though highly resilient to it, many services associated with pine forests disappear in the short- or long term following fire. Increasing temperatures and drought affect the recruitment, growth and survival of pines, increase fire risk and favor the expansion of pests and diseases.

Focusing on pines, this chapter describes the main fire-related traits that contribute to plant fitness in response to fire. First we describe the most relevant fire-adaptive traits, and discuss their evolutionary history and syndromes. Next we compare the fire-adaptive traits of Mediterranean pine species in relation to their native habitats.

Pine and mixed forests are emblematic of the Mediterranean region, extending from the thermo- to mountainous Mediterranean bioclimatic zone. Here, we attempt a brief review of species richness, spatiotemporal diversity and surface activity of soil invertebrate communities in various Mediterranean pure pine forests and mixed forests. In addition, we discuss the effects of methodological issues and knowledge gaps in systematics and ecology on the research of soil fauna. The high spatiotemporal complexity of soil invertebrate communities characteristic of the broadleaf, sclerophyllous and phryganic formations is also recorded in the pine and mixed forests of this region, reflecting the spatial patchiness of parent rock material, vegetation, and humus forms as well as the accentuated temporal variation of climatological parameters around the Mediterranean Basin.

International audience; Our ability to predict the identity of future invasive alien species is largely based upon knowledge of prior invasion history. Emerging alien species-those never encountered as aliens before-therefore pose a significant challenge to biosecurity interventions worldwide. Understanding their temporal trends, origins, and the drivers of their spread is pivotal to improving prevention and risk assessment tools. Here, we use a database of 45,984 first records of 16,019 established alien species to investigate the temporal dynamics of occurrences of emerging alien species worldwide. Even after many centuries of invasions the rate of emergence of new alien species is still high: Onequarter of first records during 2000-2005 were of species that had not been previously recorded anywhere as alien, though with large variation across taxa. Model results show that the high proportion of emerging alien species cannot be solely explained by increases in well-known drivers such as the amount of imported commodities from historically important source regions. Instead, these dynamics reflect the incorporation of new regions into the pool of potential alien species, likely as a consequence of expanding trade networks and environmental change. This process compensates for the depletion of the historically important source species pool through successive invasions. We estimate that 1-16% of all species on Earth, depending on the taxonomic group, qualify as potential alien species. These results suggest that there remains a high proportion of emerging alien species we have yet to encounter, with future impacts that are difficult to predict.

This paper aims to determine the main factors that shape the spatial patterns of alien plant species occurrence across Natura 2000 Special Areas of Conservation (SACs) in Greece, and quantify their influence. A series of spatial analysis techniques for the development of a spatial database of the factors involved, followed by a boosted negative binomial Generalised Additive Model for location scale and shape, were implemented. Native plant species richness, topography and hydrography, human population density, and a spatial preference to the northern-western sites are the key factors that explain the variation in the occurrence of alien plant species. Native plant species richness and human population density have a positive effect on alien plant species presence, while topography aspects, such as elevation and slope, and the distance from the hydrographical network a negative one. All factors are indirectly linked to propagule pressure emphasizing the importance of human activities for the efforts on managing protected areas.

In this study we analysed a novel tree-growth dataset, inferred from annual ring-width measurements, of 7 forest tree species from 12 mountain regions in Greece, in order to identify tree growth - climate relationships. The tree species of interest were: Abies cephalonica, Abies borisii-regis, Picea abies, Pinus nigra, Pinus sylvestris, Fagus sylvatica and Quercus frainetto growing across a gradient of climate conditions with mean annual temperature ranging from 5.7 to 12.6°C and total annual precipitation from 500 to 950mm. In total, 344 tree cores (one per tree) were analysed across a network of 20 study sites. We found that water availability during the summer period (May-August) was a strong predictor of interannual variation in tree growth for all study species. Across species and sites, annual tree growth was positively related to summer season precipitation (PSP). The responsiveness of annual growth to PSP was tightly related to species and site specific measurements of instantaneous photosynthetic water use efficiency (WUE), suggesting that the growth of species with efficient water use is more responsive to variations in precipitation during the dry months of the year. Our findings support the importance of water availability for the growth of mountainous Mediterranean tree species and highlight that future reductions in precipitation are likely to lead to reduced tree-growth under climate change conditions.

The Convention on Biological Diversity (CBD) pathways classification framework used in the implementation of the European Union’s (EU) Regulation 1143/2014 on invasive alien species (IAS Regulation) has recently been adopted by the European Alien Species Information Network (EASIN), the official information system supporting the implementation of the IAS Regulation. In the current paper, the result of an alignment of the primary introduction pathways of all alien plants in Europe included in the EASIN catalogue is presented, based on the CBD framework. In total, 6,250 alien plant taxa (marine plants excluded), both alien to Europe (native range outside Europe) and alien in Europe (native range partially in Europe) are reported. Altogether 5,175 plant taxa had their primary introduction pathway aligned based on the CBD framework, while for the rest the pathway remains unknown. In addition, the taxonomy, year and country of its first record in the wild are provided for each taxon. Our analyses reveal that the main primary introduction pathways of alien plants into Europe are linked to accidental escapes from ornamental and horticultural activities. Northwestern European countries seem to act as the main gateway areas of alien plants into Europe. Recent first observations of new alien taxa growing spontaneously exhibit a contemporary accelerating trend for plants alien to Europe, particularly linked to ornamental and horticultural activities. On the other hand, the number of new plants alien in Europe seems to have stabilized over the last few decades. The present work can assist in the prioritization of introduction pathways control, with the target of slowing down the rate of alien plants introductions into Europe, following also the requirements of the IAS Regulation.

The Mediterranean Basin is expected to face warmer and drier conditions in the future, following projected increases in temperature and declines in precipitation. The aim of this study is to explore how forests dominated by Abies borisii-regis, Abies cephalonica, Fagus sylvatica, Pinus nigra and Quercus frainetto will respond under such conditions. We combined an individual-based model (GREFOS), with a novel tree ring data set in order to constrain tree diameter growth and to account for inter- and intraspecific growth variability. We used wood density data to infer tree longevity, taking into account inter- and intraspecific variability. The model was applied at three 500-m-wide elevation gradients at Taygetos in Peloponnese, at Agrafa on Southern Pindos and at Valia Kalda on Northern Pindos in Greece. Simulations adequately represented species distribution and abundance across the elevation gradients under current climate. We subsequently used the model to estimate species and functional trait shifts under warmer and drier future conditions based on the IPCC A1B scenario. In all three sites, a retreat of less drought-tolerant species and an upward shift of more drought-tolerant species were simulated. These shifts were also associated with changes in two key functional traits, in particular maximum radial growth rate and wood density. Drought-tolerant species presented an increase in their average maximal growth and decrease in their average wood density, in contrast to less drought-tolerant species.

Fire affects and is affected by leaf functional traits indicative of resource allocation trade-offs. Global change drivers constrain both the resource-use strategies and flammability of coexisting species. However, small attention has been given in identifying links among flammability and plant economics. Ambiguity comes from the fact that flammability is a multidimensional trait. Different flammability attributes (i.e. ignitibility, sustainability, combustibility and consumability) have been used to classify species, but no widely-accepted relationships exist between attributes. We hypothesised that flammability is a spectrum (defined by its four attributes) and the alternative flammability syndromes of coexisting species can be captured by their resource-use strategies. Furthermore, we argue that flammability syndromes are adaptive strategies that ensure persistence in the post-fire community. We conducted a large-scale study to estimate all flammability attributes on leaves from nine, dominant, thermo-Mediterranean species with alternative resource-use and fire-response strategies across a wide environmental and geographic gradient. We assessed the interdependence among attributes, and their variation across ecological scales (genus, species, individual, site and region). Furthermore, we collected 10 leaf functional traits, conducted a soil study and extracted long-term climatological data to quantify their effect on flammability attributes. We found that leaf flammability in thermo-Mediterranean vegetation is a continuous two-dimensional spectrum. The first dimension, driven by leaf shape and size, represents heat release rate (combustibility vs. sustainability), while the second, controlled by leaf economics, presents ignition delay and total heat release (i.e. consumability). Alternative flammability syndromes can increase fitness in fire-prone communities by offering qualitative differences in survival or reproduction. Trade-offs and constraints that control the distribution of resource-use strategies across environmental gradients appeared to drive leaf flammability syndromes as well. Tying the flammability spectrum with resource allocation trade-offs on a global scale can help us predict future ecosystem properties and fire regimes and illustrate evolutionary constraints on flammability.

Vascular plants have been found to align along globally-recognised resource-allocation trade-offs among specific functional traits. Genetic constrains and environmental pressures limit the spectrum of viable resource-use strategies employed by plant species. While conspecific plants have often been described as identical, intraspecific variation facilitates species coexistence and evolutionary potential. This study attempts to link an individual's phenotype to its environmental tolerance and ecosystem function. We hypothesised that: (1) seasonal variation in water availability has selected for tight phenotypic integration patterns that shape Mediterranean vegetation; however, (2) coexisting species employ alternative resource-use strategies to avoid competitive exclusion; specifically (3) species with smaller climatic niches (i.e. potential distributions) display higher functional diversity. We examined the interdependence among and the sources of variation within 11 functional traits, reflecting whole-plant economics (e.g. construction costs, hydraulics, defences, water storage capacity), from nine dominant, thermo-Mediterranean species measured across a wide environmental and geographic gradient. Furthermore, we delineated the phenotypic and climatic hypervolumes of each studied species to test for climatic niche overlap and functional distinctiveness. By adopting this multidimensional trait-based approach we detected fundamental phenotypic integration patterns that define thermo-Mediterranean species regardless of life history strategy. The studied traits emerged intercorrelated shaping a resource-allocation spectrum. Significant intraspecific variability in most measured traits allowed for functional distinctiveness among the measured species. Higher functional diversity was observed in species restricted within narrower climatic niches. Our results support our initial hypotheses. The studied functional traits collectively formed an integrated space of viable phenotypic expressions; however, phenotypic plasticity enables functionally distinctive species to succeed complementary in a given set of environmental conditions. Functional variability among coexisting individuals defined species' climatic niches within the trait-spectrum permitted by Mediterranean conditions. Ultimately, a species establishment in a locality depends on the extent that it can shift its trait values.

The identification of research questions with high relevance for biodiversity conservation is an important step towards designing more effective policies and management actions, and to better allocate funding among alternative conservation options. However, the identification of priority questions may be influenced by regional differences in biodiversity threats and social contexts, and to variations in the perceptions and interests of different stakeholders. Here we describe the results of a prioritization exercise involving six types of stakeholders from the Mediterranean biome, which includes several biodiversity hotspots spread across five regions of the planet (Europe, Africa, North and South America, and Australia). We found great heterogeneity across regions and stakeholder types in the priority topics identified and disagreement among the priorities of research scientists and other stakeholders. However, governance, climate change, and public participation issues were key topics in most regions. We conclude that the identification of research priorities should be targeted in a way that integrates the spectrum of stakeholder interests, potential funding sources and regional needs, and that further development of interdisciplinary studies is required. The key questions identified here provide a basis to identify priorities for research funding aligned with biodiversity conservation needs in this biome. AFB, Grant/Award Number: 17008; Fundação para a Ciência e a Tecnologia, Grant/Award Number: IF/01053/2015; National Research Foundation Incentive Funding, Grant/Award Number: 103841; REN Biodiversity Chair; EDP Biodiversity Chair; COMPETE, Grant/Award Number: PTDC/AAG‐MAA/2261/2014 POCI‐01‐0145‐FEDER‐356 016824; The Society for Conservation Biology

Mediterranean shrublands are generally water-limited and fire-driven ecosystems. Seed-based post-fire regeneration may be affected by varying rainfall patterns, depending on species sensitivity to germinate under water stress. In our study, we considered the germination response to water stress in four species from several sites across the Mediterranean Basin. Seeds of species with a hard coat (Cistus monspeliensis, C. salviifolius, Cistaceae, Calicotome villosa, Fabaceae) or soft coat (Erica arborea, Ericaceae), which were exposed or not to a heat shock and smoke (fire cues), were made to germinate under water stress. Final germination percentage, germination speed and viability of seeds were recorded. Germination was modelled using hydrotime analysis and correlated to the water balance characteristics of seed provenance. Water stress was found to decrease final germination in the three hard-seeded species, as well as reduce germination speed. Moreover, an interaction between fire cues and water stress was found, whereby fire cues increased sensitivity to water stress. Seed viability after germination under water stress also declined in two hard-seeded species. Conversely, E. arborea showed little sensitivity to water stress, independent of fire cues. Germination responses varied among populations of all species, and hydrotime parameters were not correlated to site water balance, except in E. arborea when not exposed to fire cues. In conclusion, the species studied differed in germination sensitivity to water stress; furthermore, fire cues increased this sensitivity in the three hard-seeded species, but not in E. arborea. Moreover, populations within species consistently differed among themselves, but these differences could only be related to the provenance locality in E. arborea in seeds not exposed to fire cues.

This study is focused on the development, implementation and evaluation of an environmental education programme for secondary education students. The programme was entitled ‘Τhe effects of fire on the soil system’ and it was implemented during the school period of 2008. Twenty-four (24) students (aged from 15 to 20) coming from Lidoriki Secondary School (Central Greece) participated in the programme, which was based on Project Method. The programme consisted of one theoretical part (achievement of cognitive and affective goals) and one experimental part (achievement of cognitive and psychomotor goals). Initial, formative and summative assessments were implemented during the course of the programme, by means of questionnaires, observation of students’ teamwork and examination of their work sheets. The questionnaire analysis highlighted students’ misconceptions regarding the subject, revealed positive changes in students’ attitudes as a result of their participation in the programme, as well as satisfactory...

Understanding how future climate periods influence fire behaviour is important for organizing fire suppression strategy and management . The meteorological factors are the most critical parameters affecting fire behaviour in natural landscapes; hence, predicting climate change effects on fire behaviour could be an option for optimizing firefighting resource management. In this study, we assessed climate change impacts on fire behaviour parameters (rate of fire growth, rate of spread and fireline intensity) for a typical Mediterranean landscape of Greece. We applied the minimum travel time fire simulation algorithm by using the FlamMap software to characterize potential response of fire behaviour for three summer periods. The results consisted of simulated spatially explicit fire behaviour parameters of the present climate (2000) and three future summer periods of 2050, 2070 and 2100, under the A1B emissions scenario. Statistical significant differences in simulation outputs among the four examined periods were obtained by using the Tukey’s significance test. Statistical significant differences were mainly obtained for 2100 compared to the present climate due to the significant projected increase in the wind speed by the end of the century. The analysis and the conclusions of the study can be important inputs for fire suppression strategy and fire management (deployment of fire suppression resources, firefighter safety and exposure, transportation logistics) quantifying the effect that the expected future climate periods can have on fire suppression difficulty in Mediterranean landscapes.

Aim Although all five of the major mediterranean-climate ecosystems (MCEs) of the world are recognized as loci of high plant species diversity and endemism, they show considerable variation in regional-scale richness. Here, we assess the role of stable Pleistocene climate and Cenozoic topography in explaining variation in regional richness of the globe's MCEs. We hypothesize that older, more climatically stable MCEs would support more species, because they have had more time for species to accumulate than MCEs that were historically subject to greater topographic upheavals and fluctuating climates. Location South-western Africa (Cape), south-western Australia, California, central Chile and the eastern (Greece) and western (Spain) Mediterranean Basin. Methods We estimated plant diversity for each MCE as the intercepts of species–area curves that are homogeneous in slope across all regions. We used two down-scaled global circulation models of the Last Glacial Maximum (LGM) to quantify climate stability by comparing the change in the location of MCEs between the LGM and present. We quantified the Cenozoic topographic stability of each MCE by comparing contemporary topographic profiles with those present in the late Oligocene and the early Pliocene. Results The most diverse MCEs – Cape and Australia – had the highest Cenozoic environmental stability, and the least diverse – Chile and California – had the lowest stability. Main conclusions Variation in plant diversity in MCEs is likely to be a consequence not of differences in diversification rates, but rather the persistence of numerous pre-Pliocene clades in the more stable MCEs. The extraordinary plant diversity of the Cape is a consequence of the combined effects of both mature and recent radiations, the latter associated with increased habitat heterogeneity produced by mild tectonic uplift in the Neogene.

Pinus nigra (black pine) is an ecologically and economically important species widely distributed around the Mediterranean Basin. P. nigra ecosystems have recently been affected by high severity fires occurring over the mountainous forest ecosystems of Southern Europe. The aim of this study is to investigate the post-fire regeneration patterns of black pine after a high severity crown fire which occurred on Mt Taygetos in Southern Greece. A network of 18 sites was selected to study black pine natural post-fire regeneration. Regeneration density was higher at the edges of patches that have remained unburned within the periphery of fire (0.406 individuals/m2) as compared to isolated burned areas (0.007 individuals/m2) although a significant between sites heterogeneity was recorded. Boosted regression trees analysis was used to explore the effects of environmental and microhabitat variables on black pine post-fire regeneration. The number of fires a site has experienced had a negative effect on regeneration density, while the presence of recovering ferns had a positive effect. The most important variable related to the black pine post-fire regeneration was distance from unburned patches. The result of the current study substantiates the importance of maintaining fire-resistant stands with large trees that are more likely to survive after a surface fire and which can also serve as seed sources for the recolonization of the burned area after severe crown fires.

The aims of this study were to map and analyze land use/land cover transitions and landscape changes in the Parnitha and Penteli mountains, which surround the Athens metropolitan area of Attica, Greece over a period of 62 years. In order to quantify the changes between land categories through time, we computed the transition matrices for three distinct periods (1945–1960, 1960–1996, and 1996–2007), on the basis of available aerial photographs used to create multi-temporal maps. We identified systematic and stationary transitions with multi-level intensity analysis. Forest areas in Parnitha remained the dominant class of land cover throughout the 62 years studied, while transitional woodlands and shrublands were the main classes involved in LULC transitions. Conversely, in Penteli, transitional woodlands, along with shrublands, dominated the study site. The annual rate of change was faster in the first and third time intervals, compared to the second (1960–1996) time interval, in both study areas. The category level analysis results indicated that in both sites annual crops avoided to gain while discontinuous urban fabric avoided to lose areas. At the transition level of analysis, similarities as well as distinct differences existed between the two areas. In both sites the gaining pattern of permanent crops with respect to annual crops and the gain of forest with respect to transitional woodland/shrublands were stationary across the three time intervals. Overall, we identified more systematic transitions and stationary processes in Penteli. We discussed these LULC changes and associated them with human interference (activity) and other major socio-economic developments that were simultaneously occurring in the area. The different patterns of change of the areas, despite their geographical proximity, throughout the period of analysis imply that site-specific studies are needed in order to comprehensively assess the driving forces and develop models of landscape transformation in Mediterranean areas.

Fires affecting large areas usually create a mosaic of recovering plant communities reflecting their pre-fire composition and local conditions of burning. However, post-fire recovery patterns may also reveal the effects of landscape heterogeneity on the natural regeneration process of plant communities. This study combines field data and remote sensing image interpretation techniques to assess the role of various landscape characteristics in the post-fire recovery process in a mountainous region of Greece burned by a severe wildfire. Remote sensing techniques were used to accurately map secluded, large burned areas. By introducing a temporal component, we explored the correlation between post-fire regeneration and underlying topography, soils and basement rock. Pre-fire forest cover was reduced by more than half 8 years after fire. Regarding the dominant pre-fire forest trees, Abies cephalonica did not regenerate well after fire and most pre-fire stands were converted to grasslands and shrublands. In contrast, Pinus nigra regenerated sufficiently to return to its pre-fire cover, especially in areas underlain by softer basement rock. The use of different time series of high-resolution images improved the quality of the results obtained, justifying their use despite their high cost.

Mountains of the northern Mediterranean basin face two major threats under global change. Aridity and available fuel are both expected to increase because of climatic and land-use changes, increasing fire danger. There may already be signs of such effects in the case of the Pinus nigra and Abies cephalonica forests on Mt. Taygetos (southern Greece). We reconstructed climate (mid- to late-fire-season drought) using tree-rings for the last 150 years and compared it with the mountain’s fire history reconstructed from P. nigra fire scars. Seven, out of the ten, large fires Mt. Taygetos experienced were associated with below-normal precipitation (P) or above-normal maximum temperature (T max). The largest fires occurred in late summer of 1879, 1944, 1998, and 2007. However, only the recent fires (1998 and 2007) had both low P and high T max, also confirmed from long-term meteorological data. The synergy between climate and fuel availability may explain the very high intensity of 1998 and 2007 fires that burned mostly as stand-replacing crown fires. The other two large fire events (1879 and 1944) most likely occurred under reduced availability in burning fuel and were related to above-normal T max. Our findings are among the first based on long-term and site-specific empirical data to support the prediction that Mediterranean mountainous areas will face a very large threat from wildfires in the twenty-first century, if socioeconomic changes leading to land abandonment and thus burning fuel accumulation are combined with the drought intensification projected for the region under global warming.

In the past few decades there is an increasing trend of both fire activity and area burned in many regions of the world. Moreover, there is a worldwide concern regarding the increasing presence of crown fires in forest types that were historically prone to surface fires. Among the recently affected mountainous forest ecosystems are those of Pinus nigra, an ecologically and economically important species that is widely distributed around the Mediterranean Basin. Mount Taygetos, a mountainous landscape in Peloponnese, Greece, that was severely burned in 2007, was selected to carry out the first landscape-scale fire history reconstruction in P. nigra of the eastern Mediterranean. The aims of the study were to investigate whether fire-regime attributes can be reconstructed from fire-scarred trees and also to examine the consistency of fire occurrence and spatial extent through time within the area selected. Partial cross-sections were sampled within the perimeters of the more recent known large fires in the region, those of 2007 and 1998. The overall mean fire interval between 1845 and 2007 was 4.9 years, while for the larger fires this time window was 16.2 years. Even at the individual-sample scale, with the sample mean fire interval equaling 29.5 years, the fire frequency still falls within the range of the ‘‘predictable stand-thinning fire’’ regime. The majority of fire scars recorded were dated to the warm and dry season of summer to fall. During the last 165 years of fire reconstruction, neither fire frequency nor percentage of trees scarred by fires varied significantly. Nevertheless, the size of the area burned as well as the type of fire seem to have changed, with the 2007 event being the most extended crown fire encountered so far. Our study has provided additional evidence that P. nigra is indeed a fire-resistant tree species provided that it is exposed to surface fires, even if they are recurrently occurring. Shifts from this pattern may lead to local extirpation of the species, as in the case of severe and extended crown fires.

The use of spatially explicit fire spread models to assess fire propagation and behaviour has several applications for fire management and research. We used the FARSITE simulator to predict the spread of a set of wildfires that occurred along an east–west gradient of the Euro-Mediterranean countries. The main purpose of this work was to evaluate the overall accuracy of the simulator and to quantify the effects of standard vs custom fuel models on fire simulation performance. We also analysed the effects of different fuel models and slope classes on the accuracy of FARSITE predictions. To run the simulations, several input layers describing each study area were acquired, and their effect on simulation outputs was analysed. Site-specific fuel models and canopy inputs were derived either from existing vegetation information and field sampling or through remote-sensing data. The custom fuel models produced an increase in simulation accuracy, and results were nearly unequivocal for all the case studies examined. We suggest that spatially explicit fire spread simulators and custom fuel models specifically developed for the heterogeneous landscapes of Mediterranean ecosystems can help improve fire hazard mapping and optimise fuel management practices across the Euro-Mediterranean region.

WOS: 000422633100002, The European Alien Species Information Network (EASIN) aims to facilitate the exploration of alien species information in Europe, and is recognized as the information system supporting European Union Member States in the implementation of the recently published Invasive Alien Species Regulation. In this paper, we present the role and activities of the EASIN Editorial Board (EB), which is responsible for the quality assurance, safeguarding and constant improvement of EASIN. The EB is supported by a web platform that facilitates online discussions about alien species. This platform creates a virtual community by providing a forum-like interface that is moderated by the EB Members but is freely accessible to the scientific community and the general public. It allows all registered users to make comments, raise questions and share experience and expertise on alien species in Europe. Moreover, it provides a means for exchanging opinions and solving disputes in a transparent way. The overall EB activity is commonly agreed upon procedures and standards., European Commission's Directorate-General for Environment (DG ENV), The authors wish to thank the European Commission's Directorate-General for Environment (DG ENV) for their support. We thank also the anonymous reviewers for their useful comments and corrections.

Pinus halepensis forests are among the forest ecosystems in the Mediterranean Basin most affected by fire. Their distribution across lowland areas, in particular along the wildland–urban interface, increases the need to understand their ecology and responses to fire regime for their effective management. Apart from the extremely flammable tree layer, in several stands of these forests there is an increased fuel load attributed to the well-developed understorey of evergreen sclerophyllous shrubs. Taking into consideration that, in contrast with the long period required for full development of post-fire-regenerating pines, these shrubs resprout vigorously within the first post-fire weeks, it is important to explore the temporal trend of fuel accumulation to determine the risk of a second fire across a burned landscape. Two post-fire chronosequences of, in total, 12 P. halepensis stands were considered for sampling in Central Greece. The first chronosequence corresponds to pine stands characterized by the dominance of evergreen sclerophyllous shrubs in the understorey (Type 1) whereas the second chronosequence corresponds to pine stands where the cover of such shrubs was lower (Type 2). This study helps in understanding the fuel dynamics according to the type of P. halepensis forest stand and to anticipate future biomass growth. The proposed equations are simple tools, enabling land managers to estimate understorey total fuel load easily by visually recording the cover and height of the evergreen sclerophyllous shrub component, to justify understorey fuel reduction measures.

The aim of this study is to explore the burning pattern of the catastrophic wildfires that occurred in Peloponnisos, southern Greece, in 2007. These fires caused the loss of 67 lives and were recognized as the most extreme natural disaster in the country's recent history. We compare the 2007 fires against fuel availability across the landscape in the light of a null model using Monte-Carlo randomization and against the fire pattern for the preceding period, 2000-2006. Additionally we applied a multi-response permutation-procedure test, a data-driven method free from assumptions about the underlying distribution. The study contributes to the ongoing debate over the relative importance of fuel versus weather in explaining large and intense wildfires. While the majority of the 2007 wildfires burned low-elevation fire-prone ecosystems, a part of them moved to non-fire-prone ecosystems, indicating a departure from the burning pattern of recent history. The CORINE land-cover categories most affected by fire included agricultural lands highly interspersed with large areas of natural vegetation followed by sclerophyllous vegetation, transitional woodland shrubs, complex cultivation patterns and olive groves. These reflect greater fuel accumulation through the encroachment of natural vegetation in abandoned fields as well as changing patterns of land-use. The rising proportions of humid and sub-humid areas burned are clearly related to weather patterns. The synergistic effect between fuel and weather helps explain the unusually large 2007 wildfires in Peloponnisos. This change may imply a climatically driven alteration of the established fire-regime promoted by fuel accumulation that portends major ecological consequences. The ecological disaster foreseen is justified by the lack of specific adaptations to cope with fire in non fire-prone plant communities. (C) 2011 Elsevier B.V. All rights reserved. Agricultural and Forest Meteorology

Aim Many Australian Acacia species have been planted around the world, some are highly valued, some are invasive, and some are both highly valued and invasive. We review global efforts to minimize the risk and limit the impact of invasions in this widely used plant group.

The reproductive biology of the endemic to Greece Abies cephalonica Loudon, including the phenology of the reproductive life cycle, cone production in relation to plant age and the required seed germination conditions, was studied. All individuals growing within 20 permanent plots of 100 m2 each established in 11 different locations covering the entire strictly protected area of Mount Aenos National Park (Cephalonia) were monitored over a period of 4 years. The cones are formed on the upper part of the previous year’s branches, mostly at the upper crown half of the reproductive individuals (over 53 years old). Female flowers are pollinated in spring and cone maturation lasts until the beginning of autumn, when seed dispersal occurs. The annual production of cones per individual varied significantly, revealing masting behavior for this tree. This behavior was also expressed in the number of trees producing cones, as well as the percentage of sound seeds per cone. A significant difference in the mass and the length of the cones between the years of low and high cone production was observed, being higher in the years of massive cone production. Similar germination percentages were observed in full darkness or under “canopy light” and “sun light”, provided that the seeds were previously stratified for 6 weeks. It is concluded that A. cephalonica exhibits plasticity expressed in its reproductive behavior for alternating years of high to low cone production and in its seed germination for an array of habitat light conditions.

Aim To investigate alien plant species invasion levels in different habitats and alien species traits by comparing the naturalized flora in different areas of the same biogeographical region.

The aim of the paper is the state-of-the-art assessment of the alien flora of Greece and its traits. The dataset consists of a total of 343 alien taxa, including 49 archaeophytes. The taxonomy, life traits and habitat of the 294 neophytes are analysed vs their naturalisation status. Out of the 122 (41%) naturalised neophytes, 50 are identified as exhibiting invasive behaviour. Poaceae, Asteraceae, Amaranthaceae, Solanaceae, Fabaceae, and Polygonaceae are the plant families richest in alien taxa. The majority of them are of American origin, followed by those of Asiatic and Mediterranean origin. The neophytes are predominantly herbs, most of them annuals. Yet, the perennial life cycle is equally frequent with the annual one and the proportion of phanerophytes in the alien flora is increased compared to the one of the native flora. Regarding flowering traits, most of the aliens have a long flowering period (over 1 month) and flower in late spring, summer and autumn, when few of the native plants are in bloom. Vertebrate zoochory and anemochory are the two dispersal modes mostly utilised by the alien plants (43 and 28%, respectively), while more than one dispersal mechanisms are functional for 56% of them. Artificial habitats have the highest frequencies of alien plants. The natural habitats with the highest numbers of aliens are the coastal ones and inland surface waters. Opuntia ficus-barbarica, Ailanthus altissima, Oxalis pes-caprae, Erigeron bonariensis, Amaranthus albus and Symphyotrichum squamatum are typical cases of plants characterised as invasive, having established in almost all the habitat groups identified. The diversity of the ecological characteristics of the plants suggests a potential of impacts that needs to be further assessed.