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Invasive alien species are among the main global drivers of biodiversity loss posing major challenges to nature conservation and to managers of protected areas. The present study applied a methodological framework that combined invasive Species Distribution Models, based on propagule pressure, abiotic and biotic factors for 14 invasive alien plants of Union concern in Italy, with the local interpretable model-agnostic explanation analysis aiming to map, evaluate and analyse the risk of plant invasions across the country, inside and outside the network of protected areas. Using a hierarchical invasive Species Distribution Model, we explored the combined effect of propagule pressure, abiotic and biotic factors on shaping invasive alien plant occurrence across three biogeographic regions (Alpine, Continental, and Mediterranean) and realms (terrestrial and aquatic) in Italy. We disentangled the role of propagule pressure, abiotic and biotic factors on invasive alien plant distribution and projected invasion risk maps. We compared the risk posed by invasive alien plants inside and outside protected areas. Invasive alien plant distribution varied across biogeographic regions and realms and unevenly threatens protected areas. As an alien's occurrence and risk on a national scale are linked with abiotic factors followed by propagule pressure, their local distribution in protected areas is shaped by propagule pressure and biotic filters. The proposed modelling framework for the assessment of the risk posed by invasive alien plants across spatial scales and under different protection regimes represents an attempt to fill the gap between theory and practice in conservation planning helping to identify scale, site, and species-specific priorities of management, monitoring and control actions. Based on solid theory and on free geographic information, it has great potential for application to wider networks of protected areas in the world and to any invasive alien plant, aiding improved management strategies claimed by the environmental legislation and national and global strategies.

Riparian ecosystems, in long-time developed regions, are among the most heavily impacted by human activities; therefore, the distribution of tree riparian species, such as

In this contribution, the conservation status assessment of four vascular plants according to IUCN categories and criteria are presented. It includes the assessments of Aurinialeucadea (Guss.) K.Koch, Chondrillachondrilloides (Ard.) H.Karst., Daphnecneorum L., and Ophioglossumazoricum C.Presl at regional level (Italy).

In this contribution, new data concerning the Italian distribution of alien vascular flora are presented. It includes new records, exclusions, confirmations, and status changes for Italy or for Italian administrative regions for taxa in the genera Acer, Amaranthus, Araujia, Aubrieta, Avena, Bidens, Calycanthus, Celtis, Elaeagnus, Eragrostis, Euonymus, Fallopia, Ficus, Hedera, Lantana, Ligustrum, Ludwigia, Morus, Oenothera, Opuntia, Oxalis, Parkinsonia, Paspalum, Paulownia, Platycladus, Pleuropterus, Rumex, Salvia, Senecio, Setaria, Syagrus, Tradescantia, Trifolium and Yucca. Furthermore, a new combination in the genus Vicia is proposed.

Invasive alien plants are a major threat to biodiversity and they contribute to the unfavourable conservation status of habitats of interest to the European Community. In order to favour implementation of European Union Regulation no. 1143/2014 on invasive alien species, the Italian Society of Vegetation Science carried out a large survey led by a task force of 49 contributors with expertise in vegetation across all the Italian administrative regions. The survey summed up the knowledge on impact mechanisms of invasive alien plants in Italy and their outcomes on plant communities and the EU habitats of Community Interest, in accordance with Directive no. 92/43/EEC. The survey covered 241 alien plant species reported as having deleterious ecological impacts. The data collected illustrate the current state of the art, highlight the main gaps in knowledge, and suggest topics to be further investigated. In particular, the survey underlined competition as being the main mechanism of ecological impact on plant communities and Natura 2000 habitats. Of the 241 species, only Ailanthus altissima was found to exert an ecological impact on plant communities and Natura 2000 habitats in all Italian regions; while a further 20 species impact up to ten out of the 20 Italian administrative regions. Our data indicate that 84 out of 132 Natura 2000 Habitats (64%) are subjected to some degree of impact by invasive alien plants. Freshwater habitats and natural and semi-natural grassland formations were impacted by the highest number of alien species, followed by coastal sand dunes and inland dunes, and forests. Although not exhaustive, this research is the first example of nationwide evaluation of the ecological impacts of invasive alien plants on plant communities and Natura 2000 Habitats.

Italy has a rich natural heritage, which is dangerously under pressure. In recent years, there is an increased awareness of the crucial role of plants in ecosystem functioning and in providing ecosystem services. Consequently, an updated Red List of the Italian vascular flora was compiled in this work, at the request of the Ministry for Environment, Land and Sea Protection, with the scientific support of the Italian Botanical Society. The IUCN Red List criteria were applied to 2,430 Italian native vascular plant taxa to assess their current extinction risk and to highlight the major threats affecting the Italian flora. Our results revealed that 54 taxa (2.2% of the assessed taxa) are extinct or possibly extinct at regional level, while 590 taxa (24.3%) were assigned to a risk category. Moreover, 404 taxa (16.6%) were categorized as Data Deficient. The Italian vascular flora is primarily threatened by habitat modifications due to anthropic disturbance and, especially, to agriculture, tourism and residential development. Coastal areas and lowlands, where anthropogenic impacts and ecosystem destruction are more pronounced, host the greatest number of extinct or declining taxa. Our results represent an important baseline to establish conservation priorities, legislative choices and intervention strategies on a national scale.

In this contribution, new data concerning bryophytes, fungi, and lichens of the Italian flora are presented. It includes new records and confirmations for the bryophyte genera Barbula, Fissidens, Gymnostomum, Jungermannia, Riccia, and Scapania, the fungal genera Hyalopsora and Urocystis and the lichen genera Arthothelium, Chaenotheca, Lepraria, Lobaria, Miriquidica, Parmelia, Rinodina, Solenopsora, Thelopsis and Xanthoparmelia.

Taxa endemic to a country are key elements for setting national conservation priorities and for driving conservation strategies, since their persistence is entirely dependent on national policy. We applied the IUCN Red List categories to all Italian endemic vascular plants (1340 taxa) to assess their current risk of extinction and to highlight their major threats. Our results revealed that six taxa are already extinct and that 22.4% (300 taxa) are threatened with extinction, while 18.4% (247; especially belonging to apomictic groups) have been categorized as Data Deficient. Italian endemic vascular plants are primarily threatened by natural habitat modification due to agriculture, residential and tourism development. Taxa occurring in coastal areas and lowlands, where anthropogenic impacts and habitat destruction are concentrated, display the greatest population decline and extinction. The national network of protected areas could be considered effective in protecting endemic-rich areas (ERAs) and endemic taxa, but ineffective in protecting narrow endemic-rich areas (NERAs), accordingly changes to the existing network may increase the effectiveness of protection. For the first time in the Mediterranean Basin biodiversity hotspot, we present a comprehensive extinction assessment for endemic plants under the full responsibility of a single country. This would provide an important step towards the prioritization and conservation of threatened endemic flora at Italian, European, and Mediterranean level. A successful conservation strategy of the Italian endemic vascular flora should implement the protected area system, solve some taxonomical criticism in poorly known genera, and should rely on monitoring threatened species, and on developing species-specific action plans.

The present contribution is part of an ongoing work promoted by the Italian Botanical Society aimed at recognizing and typifying all the taxa described from Italy and their loci classici, in order to increase their systematic knowledge and promote further studies (Domina et al. 2012, Passalacqua et al. 2014, Peruzzi et al. 2015, Brundu et al. 2017). One of these taxa is Arabis pedemontana Boissier (1843: 69), an Italian endemic (Bartolucci et al. 2018), currently accepted as Arabidopsis pedemontana (Boiss.) O’Kane & Al-Shehbaz (1997: 326).

An updated inventory of the vascular flora alien to Italy, providing details on the occurrence at regional level, is presented. The checklist includes 1597 species, subspecies, and hybrids, distributed in 725 genera and 152 families; 2 taxa are lycophytes, 11 ferns and fern allies, 33 gymnosperms, and 1551 angiosperms. 157 taxa are archaeophytes and 1440 neophytes. The alien taxa currently established in Italy are 791 (570 naturalized and 221 invasive), while 705 taxa are casual aliens, 4 are not assessed, 7 are of unknown regional distribution, 47 have not been confirmed in recent times, 3 are considered extinct or possibly extinct in the country, and 40 are doubtfully occurring in Italy. This checklist allows to establish an up-to-date number (9792) of taxa constituting the whole (native and alien) Italian flora.

The spread of the invasive and allergenic Ambrosia artemisiifolia L. in Italy was analysed and mapped using distribution data from a wide range of sources. Ambrosia artemisiifolia occupies 1057 floristic quadrants which are mostly distributed in the Po plain. The distribution obtained represents the basis to implement urgent management strategies.

The Italian vascular flora is one of the richest in the European Union and the Italian peninsula is located at the centre of the Mediterranean Basin, one of the 25 world biodiversity hotspots with an exceptional loss of habitats and species (1). Preliminary to any conservation initiative concerning plant diversity, a prioritization of the most endangered species is needed. IUCN Red List protocol is widely recognized and used to evaluate the conservation status of a species, according to its estimated extinction risk (2). Assessing the conservation status of plants endemic to an entire nation is a key challenge, because of the huge amount of data, knowledge and information required. Such a result can be achieved only through the collaboration of many specialists and an adequate financial base. “The Red List of the Italian Flora” project, promoted by the Ministry for Environment and Protection of Land and Sea General, Directorate for Protection of Nature and Sea, in collaboration with the Italian Botanical Society, started in 2013 with the aim to update the conservation status of Italian plants. In 2016 the assessment of all the vascular plants strictly endemics to Italy was completed. Considering all the Italian endemics, with the exclusion of taxonomically critical genera (i.e. Alchemilla, Hieracium, Ophrys, Pilosella, Ranunculus, Rubus and Taraxacum), a total of 1088 taxa was assessed. Three taxa are considered extinct (EX), one extinct in the wild (EW) and six are possibly extinct (CR[PE]). Around 27% of the Italian endemics are included in one of the major threat categories (CR, EN and VU), while c. 20% may become threatened with extinction in the near future (NT). Around half of the Italian endemic taxa (506) are widespread and abundant taxa (LC). Finally, 80 species (7%) were categorized as Data Deficient since the available data did not allow a robust assessment, indicating that further taxonomic and field studies should be undertaken in the next future.

Theory predicts that a small effective population size leads to slower accumulation of mutations, increased levels of genetic drift and reduction in the efficiency of natural selection. Therefore endemic species should harbor low levels of genetic diversity and exhibit a reduced ability of adaptation to environmental changes.Arabidopsis pedemontanaandArabidopsis cebennensis, two endemic species from Italy and France respectively, provide an excellent model to study the adaptive potential of species with small distribution ranges. To evaluate the genome-wide levels and patterns of genetic variation, effective population size and demographic history of both species, we genotyped 53A. pedemontanaand 28A. cebennensisindividuals across the entire species ranges with Genotyping-by-Sequencing. SNPs data confirmed a low genetic diversity forA. pedemontanaalthough its effective population size is relatively high. Only a weak population structure was observed over the small distribution range ofA. pedemontana, resulting from an isolation-by-distance pattern of gene flow. In contrary,A. cebennensisindividuals clustered in three populations according to their geographic distribution. Despite this and a larger distribution, the overall genetic diversity was even lower forA. cebennensisthan forA. pedemontana.A demographic analysis demonstrated that both endemics have undergone a strong population size decline in the past, without recovery. The more drastic decline observed inA. cebennensispartially explains the very small effective population size observed in the present population. In light of these results, we discuss the adaptive potential of these endemic species in the context of rapid climate change.

La petite massette (Typha minima Hoppe) est une espece alluviale qui occupait de vastes espaces le long des les cours d’eaux des contreforts montagnards perialpins au 18eme siecle. Son declin a commence au debut du 19eme siecle avec l’endiguement des cours d’eau, puis le colmatage et le drainage des plaines alluviales. Toutefois, l’ampleur de ce recul est encore mal connue a l’echelle du massif alpin. Cet article evalue l’ampleur du recul de Typha minima depuis le 19eme siecle en comparant les distributions actuelle et passee de cette espece. Deux cartes de distribution (actuelle et passee) ont ete contruites a partir de toutes les informations trouvees dans la litterature ainsi que sur les donnees anciennes d’herbier. D'apres ces cartes, l'extension de Typha minima etait d'environ 3170 km de rives de cours d’eau au 19eme siecle, alors qu'elle n'est plus que de 480 km actuellement (1995–2010). Le taux de regression des populations etait donc de 85% en 100 ans. Cependant, l'ampleur du recul varie entre regions. Il atteint 98% dans les Alpes du Nord et les Alpes orientales mais seulement de l’ordre de 50% en France. La plus faible regression en France s'explique par la strategie de lutte contre les crues mise en oeuvre au 19eme siecle, avec la construction de chenaux d’ecoulement relativement larges, plus favorables au maintien de l’espece.

Assisted colonization is one way of facilitating range shifts for species that are restricted in their ability to move in response to climate change. Here we conceptualize and apply a new decision framework for modelling assisted colonization of plant species prior to in situ realization. Three questions were examined: a) Is species translocation useful in a certain area? b) where and c) how long will it be successful in the future? Applying our framework to Carex foetida in Italy at the core of its distribution and its southern edge revealed that assisted colonization could be successful in short-term (2010–2039) climate conditions, partially in medium (2040–2069) but not in long-term (2070–2099) scenarios. We show that, for some species, it is likely that assisted colonization would be successful in some portions of the recipient site under current and short-term climate conditions, but over the mid- and long-term, climate changes will make species translocation unsuccessful. The proposed decision framework can help identify species that will need different conservation actions (seed banks and/or botanical gardens) when assisted colonization is unlikely to be successful. Furthermore it has broad applicability, as it can support planning of assisted migration in mountainous areas in the face of climate change.

La nuova Lista Rossa della flora Italiana comprende tutte le "policy" specie italiane e altre specie di nota conservazione e comprende 400 taxa di cui il 65% sono minacciate di estinzione. La Lista Rossa si basa su un enorme data-set georeferenziato utile per gli scopi di conservazione. - The New Red List of the Italian Flora includes all the Italian policy species and other species of known conservation concerns for a total of 400 taxa, 65% of which are threatened with extinction. The Red List is based on a huge georeferenced data-set useful for conservation purposes.

The distribution range of Primula marginata Curtis (Primulaceae) has never been fully characterized. In the present study, authors did a revision of the distribution range using herbaria material, database records and in situ populations' check-up. P. marginata was confirmed extending from Cottian to Maritime and Ligurian Alps, with few outlier occurrences in the northern Apennines. The localities previously reported from northern Piedmont (Val d'Ossola) were not confirmed. Maximum entropy model (Maxent) was used to simulate the potential distribution of P. marginata under current climate conditions. According to the distribution modelling performed, the species prefers rocky calcareous habitats mainly at high elevations, with abundant precipitation, but low moisture retention at soil level and marked temperature range between winter and summer seasons. The potential distribution area drawn by Maxent seemed to describe P. marginata at its maximum extension, and any future climate changes might cause limit...

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Englisch, Thorsten Tribsch, Andreas Holderegger, Rolf Alvarez, Nadir Niklfeld, Harald Coldea, Gheorghe Mirek, Zbigniew Moilanen, Atte Ahlmer, Wolfgang Marsan, Paolo Ajmone Bona, Enzo Bovio, Maurizio Choler, Philippe Cieslak, Elzbieta Colli, Licia Cristea, Vasile Dalmas, Jean-Pierre Frajman, Bozo Garraud, Luc Gaudeul, Myriam Gielly, Ludovic Gutermann, Walter Jogan, Nejc Kagalo, Alexander A. Korbecka, Grazyna Kuepfer, Philippe Lequette, Benoit Letz, Dominik Roman Manel, Stephanie Mansion, Guilhem Marhold, Karol Martini, Fabrizio Negrini, Riccardo Nino, Fernando Paun, Ovidiu Pellecchia, Marco Perico, Giovanni Piekos-Mirkowa, Halina Prosser, Filippo Puscas, Mihai Ronikier, Michal Scheuerer, Martin Schneeweiss, Gerald M. Schoenswetter, Peter Schratt-Ehrendorfer, Luise Schuepfer, Fanny Selvaggi, Alberto Steinmann, Katharina Thiel-Egenter, Conny van Loo, Marcela Winkler, Manuela Wohlgemuth, Thomas Wraber, Tone Gugerli, Felix Botanical Garden, Alexandru Borza/J-8087-2012; Choler, Philippe/A-7270-2008; Winkler, Manuela/K-5434-2012; Gugerli, Felix/C-9369-2009; Alvarez, Nadir/B-4318-2010; Paun, Ovidiu/F-2197-2010; Schneeweiss, Gerald/B-4344-2013; Moilanen, Atte/A-5005-2011; Marhold, Karol/B-4699-2011; Puscas, Mihai/C-4689-2012; Mansion, Guilhem/G-2123-2010; Taberlet, Pierre/D-1178-2010; Zimmermann, Niklaus/A-4276-2008 Choler, Philippe/0000-0002-9062-2721; Winkler, Manuela/0000-0002-8655-9555; Alvarez, Nadir/0000-0002-0729-166X; Paun, Ovidiu/0000-0002-8295-4937; Schneeweiss, Gerald/0000-0003-2811-3317; Marhold, Karol/0000-0002-7658-0844; Zimmermann, Niklaus/0000-0003-3099-9604 7 WILEY-BLACKWELL HOBOKEN ECOL LETT; The Convention on Biological Diversity (CBD) aims at the conservation of all three levels of biodiversity, that is, ecosystems, species and genes. Genetic diversity represents evolutionary potential and is important for ecosystem functioning. Unfortunately, genetic diversity in natural populations is hardly considered in conservation strategies because it is difficult to measure and has been hypothesised to co-vary with species richness. This means that species richness is taken as a surrogate of genetic diversity in conservation planning, though their relationship has not been properly evaluated. We tested whether the genetic and species levels of biodiversity co-vary, using a large-scale and multi-species approach. We chose the high-mountain flora of the Alps and the Carpathians as study systems and demonstrate that species richness and genetic diversity are not correlated. Species richness thus cannot act as a surrogate for genetic diversity. Our results have important consequences for implementing the CBD when designing conservation strategies.

International audience; In wide-ranging species, the genetic consequences of range shifts in response to climate change during the Pleistocene can be predicted to differ among different parts of the distribution area. We used amplified fragment length polymorphism data to compare the genetic structure of Arabis alpina, a widespread arctic-alpine and afro-alpine plant, in three distinct parts of its range: the North Atlantic region, which was recolonized after the last ice age, the European Alps, where range shifts were probably primarily altitudinal, and the high mountains of East Africa, where the contemporary mountain top populations result from range contraction. Genetic structure was inferred using clustering analyses and estimates of genetic diversity within and between populations. There was virtually no diversity in the vast North Atlantic region, which was probably recolonized from a single refugial population, possibly located between the Alps and the northern ice sheets. In the European mountains, genetic diversity was high and distinct genetic groups had a patchy and sometimes disjunct distribution. In the African mountains, genetic diversity was high, clearly structured and partially in accordance with a previous chloroplast phylogeography. The fragmented structure in the European and African mountains indicated that A. alpina disperses little among established populations. Occasional long-distance dispersal events were, however, suggested in all regions. The lack of genetic diversity in the north may be explained by leading-edge colonization by this pioneer plant in glacier forelands, closely following the retracting glaciers. Overall, the genetic structure observed corresponded to the expectations based on the environmental history of the different regions.

International audience; The population concept is central in evolutionary and conservation biology, but identifying the boundaries of natural populations is often challenging. Here, we present a new approach for assessing spatial genetic structure without the a priori assumptions on the locations of populations made by adopting an individual-centred approach. Our method is based on assignment tests applied in a moving window over an extensively sampled study area. For each individual, a spatially explicit probability surface is constructed, showing the estimated probability of finding its multilocus genotype across the landscape, and identifying putative migrants. Population boundaries are localized by estimating the mean slope of these probability surfaces over all individuals to identify areas with genetic discontinuities. The significance of the genetic discontinuities is assessed by permutation tests. This new approach has the potential to reveal cryptic population structure and to improve our ability to understand gene flow dynamics across landscapes. We illustrate our approach by simulations and by analysing two empirical datasets: microsatellite data of Ursus arctos in Scandinavia, and amplified fragment length polymorphism (AFLP) data of Rhododendron ferrugineum in the Alps.