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Spinescence refers to the presence of sharp appendages of various origins with ecological, evolutionary or biogeographic significance. This research was conducted to explore patterns and adaptive processes of thorns, spines and prickles in the Italian flora. We compiled an inventory of 401 spiny plants taking into account the following attributes: type of spinescence, family, biological form, chorotype, bioclimate and habitat. Then, we evaluated the incidence of plants with each attribute, the co-occurrence of various types of spinescence, the associations among spinescence types and biological forms and families, the structure of data across spinescence types, thermotypes and habitats. The spatial distributions and the adaptive processes of plants with various types of spinescence revealed that these patterns are driven by evolutionary, biogeographic and ecological factors, thus supporting the hypothesis that interactive processes of selective pressures and phylogenetic constraints have influenced the evolution of spinescences. [ABSTRACT FROM AUTHOR]

Abstract: All known populations of the Sardinian endemic Centaurea filiformis Viv. (Asteraceae) were studied in order to understand the impact of both geographic and ecological factors on the genetic structuring of this species. Fourteen populations and 234 individuals were sampled. The demographic structure of the populations and the reproductive ecology were estimated in 28 plots. Population genetic analyses were based on SSR markers. Genetic structure was investigated by spatial Bayesian methods. Average densities of 0.51 individuals m−2 were detected, with a prevalence of adults. Ten species of pollinators were identified; C. filiformis ability to self‐pollinate and myrmecochory were demonstrated experimentally. The populations displayed an average heterozygosity value of He = 0.576 and high genetic differentiation (overall FST = 0.218). Bayesian analysis suggests that five is the most probable number of gene pools of origin. A strong correlation between geographic distances and genetic distances among populations was highlighted. The demographic population structure of C. filiformis is dominated by adults, suggesting that it is a stable‐regressive or senile species, investing more in local persistence than colonisation ability. Despite the scattered distribution, the populations studied do not present evidence of genetic erosion. The analysis of genetic differentiation reveals very high differentiation levels among populations, thus indicating that effective barriers exist against gene flow. A general conclusion is that population distribution results in a clear genetic structure for the populations studied, and that geography and not ecology is shaping the present distribution of this species. [ABSTRACT FROM AUTHOR]

We analyzed the archaeobotanical remains from the Mediterranean Medieval village of Geridu (Sardinia-Italy) in order: (1) to formulate hypotheses concerning different uses of woody plants; (2) to reconstruct the distribution patterns of charcoals and to compare them with the results of the archeological interpretation and (3) to describe the agricultural activities and cultural landscape around the village. In total, 29 plant taxa were identified from charcoals and 14 from carpological remains. The number of charcoals and the ubiquity of plant taxa were correlated with each other (rp = 0.735;n = 29). Only the stratigraphic units referred to as the “construction layer” in the archeological interpretation significantly differed from the other archeological contexts which were related to the life and abandonment phases of the village. Some hypotheses regarding the agricultural activities of the village were formulated on the basis of carpological remains, largely of cereals and legumes. Integration of the archeological findings with information supported by the biological archive in Geridu and with knowledge of the vegetation series allowed reconstruction of the cultural landscape, which fit with the thermo- and meso-Mediterranean climate of the area. [ABSTRACT FROM PUBLISHER]

The Wikiplantbase project, started in 2013, provides a framework where the full set of georeferenced floristic records of Tuscany and Sardinia can be entered, stored, updated and freely accessed through the Internet. Mainly thanks to the collaboration of amateur botanists, data have accumulated quickly. All records entered by collaborators are submitted to the project coordinators, who are enabled to accept, modify, or reject them. As of 22 November 2016, Wikiplantbase #Toscana holds 116,402 verified floristic records (90% based on published literature, 5% on unpublished herbarium specimens, 5% on field observations), and Wikiplantbase #Sardegna 40,043 (77% published literature, 18% unpublished herbarium specimens, 5% on field observations ). The records include over 90% of the specific and subspecific taxa known for Tuscany and about 70% -- but rapidly growing -- of those known for Sardinia. The most recorded species are Quercus ilex L. (Fagaceae) for Tuscany and Pistacia lentiscus L. (Anacardiaceae) for Sardinia. With minor software tweaking, the online platform Wikiplantbase might be adopted in other contexts, resulting in a well connected network of regional floristic databases suited to exploit the involvement -- still largely untapped -- of nonacademic collaborators, as advocated by citizen science. [ABSTRACT FROM AUTHOR]

Mediterranean agro-silvo-pastoral systems play a key role in view of the positive contribution that they could offer to a sustainable development of European agriculture. The knowledge of the vegetation dynamics and of the processes and land uses favoring different vegetation types related to the same actual potential natural vegetation (PNV) could represent a sound reference framework for monitoring and managing plant biodiversity in these systems. The aim of the research was to evaluate plant diversity along a gradient of use intensity comparing the actual vegetation versus the PNV. The results of our research showed that in the studied Mediterranean agro-silvo-pastoral system, included in the same environmental unit, human activities enhanced plant biodiversity. Moreover, the case study presented here confirmed the effectiveness of those landscape approaches comparing actual vegetation versus the PNV for plant biodiversity monitoring and reinforced previous studies showing the effect of human activities on plant community diversity at the environmental unit scale in different biogeographical contexts. [ABSTRACT FROM AUTHOR]

Coastal habitats are particularly vulnerable to recreational impacts because these environments are highly dynamic and continually change in response to biotic and abiotic factors. Sand dune communities are worldwide characterized by high levels of biodiversity, but are often affected by human-induced impacts as those caused by tourist trampling. To understand the effects of human frequentation, trampling, and other human-induced impacts, fencing experiments have been traditionally carried out on coastal dunes. Since in touristic areas dune systems are subjected to different intensities of human frequentations rather than to opening or fencing, in this study we explore the effects of accessibility on vascular plants cover. This study tests the hypothesis that human frequentation on beaches affects spatio-temporal variability of vascular plant abundance on dunes by comparing the plant assemblages of high and low accessible sites in North-East Sardinia (Italy). Our results show that accessibility plays a crucial role in conditioning the percentage of vegetation cover in Mediterranean dunes. In fact, not only we found a perennial vegetation cover that was significantly higher in the sites with low accessibility (and consequently low frequentation), but we also showed that at the sites with high accessibility there were significant differences in vegetation cover between times of sampling (cover was higher before than after summer): on the contrary, differences in perennial vegetation cover among times were not significant at the low frequentation sites. After summer, the difference among low and high frequentation sites in species composition and cover was >90%. Multivariate analysis identified those species that play a pivotal role in differentiating the low and the high frequentation sites. Among them,Crucianella maritimaandSporobolus virginicuscan be considered as differential species. Overall, our data show vegetation and plant species responses to human-induced impacts, and are therefore important to support conservation actions in Mediterranean coastal areas interested by mass tourism. [ABSTRACT FROM PUBLISHER]

A consistent vegetation classification is an essential tool for conservation and monitoring purposes, also for semi-natural habitats such as pastures and hay meadows that are linked to traditional land use and generally considered crucial to maintain biodiversity within agricultural systems. Indeed, these habitats can be strongly affected by land abandonment or agriculture intensification. Despite their importance in the framework of the EU Habitats Directive (43/92/EEC), information on distribution, species composition, and conservation status is still lacking for many regions. To fill these gaps, we investigated from a phytosociological point of view the sheep pastures of the North-Western Sardinian trachy-basaltic sector. Three main communities were described as new: (i) perennial montane (meso-supratemperate) cattle and sheep pastures (Loto alpini-Festucetum morisianae); (ii) mixed (annual and perennial) Mediterranean (lower Thermomediterranean to lower supratemperate) sheep pastures (Ornithogalo corsici-Poetum bulbosae); and (iii) annual ploughed subnitrophilous Mediterranean and Temperate pastures (Cynosuro polybracteati-Vulpietum ligusticae). As the first two host numerous endemictaxaand show a peculiar floristic composition, we assign them a higher conservation value, testified also by their classification in two newsyntaxa:Danthonio decumbentis-Caricenion insularis(Molinio-Arrhenatheretea) andOrnithogalo corsici-Trifolienion subterranei(Poetea bulbosae), respectively. [ABSTRACT FROM PUBLISHER]

This research was undertaken with the aim of improving our knowledge of the floristic composition and spatial-temporal dynamics of plant communities in Mediterranean temporary wet habitats, and to evaluate the diversity and conservation relevance of their plant assemblages. Three different types of temporary wet habitats were monitored throughout the growing season: large temporary ponds (lTPs), small temporary ponds (sTPs), and rock pools (RPs). lTPs presented a small-scale zonation arranged in an inner, an intermediate, and a peripheral belt. A total of 98 species were recorded, of which 40 were classified as temporary wet habitat (TWH) specialists and 24 as rare. Eight different groups of plant assemblages were identified presenting space-time dynamics related to water-depth variations and flooding period. In terms of diversity, the most relevant assemblages were located in the outer belt of the lTPs and in the sTPs. The mosaic of different assemblages and their time-variability determined the presence of several types of habitats of community interest according to the Habitat Directive. This wide heterogeneity should be taken into account to ensure that all types of TWHs are considered in conservation programmes. [ABSTRACT FROM AUTHOR]

When assessing the conservation status of narrow endemic plants, life history traits must be taken into account, since endemics combine small population ranges and sizes, and long persistence with limited reproductive and dispersal ability. In this paper, we present the global assessment of the conservation status of a narrow endemic plant from the Sardinian-Corsican biogeographic province, by applying IUCN criteria and categories, together with an evaluation of some reproductive traits. Centaurea horrida Badaro (Asteraceae) is an endemic species of northern Sardinia (Italy). It is protected by the Bern Convention (Appendix I) and listed as priority species by the “Habitat” Directive (92/43/EEC, Annex II). The species appears in the 1997 IUCN Red List as “Vulnerable” (VU). With the aim of evaluating the risk of extinction and of providing management tools for the network of protected areas in which this species is present, some reproductive traits have been evaluated, and the distribution, size and structure of its population have been measured according to IUCN 2006 Guidelines. Centaurea horrida is not able to self-pollinate and its effective seed dispersal ability is limited. Its extent of occurrence is 172.43 km2 and its area of occupancy is 108 km2. Population size has been estimated at 11,719 adult individuals. Significant differences in adult densities among sites have been highlighted. The structure of the population is dominated by adult individuals (on average 68%), while the proportion of seedlings is only 7% on average. Its habitat underwent an extinction rate of 18% in 50 years. On the basis of the data gathered, the status to be assigned to C. horrida is that of “Endangered” (EN). This first attempt to evaluate the conservation status of a narrow endemic plant from the Sardinian-Corsican biogeographic province allowed us to conclude that the management of rare species must be site-specific and that there is urgent need to acquire detailed data on endangered species, especially within biodiversity hotspots, and to continuously update Annex II of the EU Habitat Directive and the IUCN Red List. [ABSTRACT FROM AUTHOR]

A phylogenetic analysis was performed based on ITS DNA sequences of fourteen samples from different sources of six species of Salicornia , the three allied genera Arthrocnemum , Sarcocornia and Halocnemum of the same tribe Salicornieae , and other genera of the subfamily Salicornioideae used in previous studies. Bassia hirsuta , Camphorosma monspeliaca (subfamily Chenopodioideae ) and four species of Suaeda (subf. Suaedoideae ) were chosen as outgroups. Results show that the annual genus Salicornia is a sister group to the perennial genera Sarcocornia , Arthrocnemum and Halocnemum . Moreover, the phylogenetic analysis based on ITS results distinguished two groups of Salicornia species which fitted with ploidy level: one group consisted of diploid species, and the second of tetraploid ones. Sarcocornia and Arthrocnemum are shown to be closely related, even though the species investigated here exhibited an evident distance between their ITS sequences. On the basis of our results, these two genera should be united. Bienertia (already separated as Bienertieae ) was confirmed as probable outgroup to the subf. Salicornioideae , while Kalidium (subf. Salicornioideae , tribe Halopeplideae ) was an outgroup to the rest of the Salicornioideae (tribe Salicornieae ). The group Allenrolfea plus Halocnemum was the most basal of the tribe Salicornieae amongst those investigated in this study. The two samples of Halocnemum strobilaceum used in this work displayed numerous changes (transitions and transversions) in their respective sequences, probably related to their morphological and chorological differentiation. On the basis of our analysis, the most probable basal chromosome number for Salicornieae appears to be 2n = 18. The same number would also be the base number for the annual genus Salicornia and the perennial Arthrocnemum ( + Sarcocornia ), with polyploidy arising independently in the two groups. [ABSTRACT FROM AUTHOR]

Listed and rare species are abundant in temporary freshwater habitats. Among them, the endemic contingent represents a crucial conservation target particularly in the areas characterized by abundant endemic flora for which the local administrations have a high level of responsibility. The aim of this research was to test how the endemic plants found in Mediterranean temporary ponds were represented in Natura 2000 network in a biodiversity hotspot of the Mediterranean region. The results of our research at regional scale pointed out that the existing Nature 2000 sites provide a limited degree of protection and that the gap analysis should be taken into account when conservation priorities are set. [ABSTRACT FROM PUBLISHER]

This new species grows in the Pre-Pyrenees (Iberian Peninsula) and belongs to Centaurea section Lepteranthus. These populations have been reported twice till date and were identified once as C. emigrantis and once as C. pectinata. Morphological data reveal that these individuals should be described as a new species. [ABSTRACT FROM AUTHOR]

This new species grows in the Pre-Pyrenees (Iberian Peninsula) and belongs to Centaurea section Lepteranthus. These populations have been reported twice till date and were identified once as C. emigrantis and once as C. pectinata. Morphological data reveal that these individuals should be described as a new species. [ABSTRACT FROM AUTHOR]

In ecological and population dynamics, the coupling between random perturbations and the Allee effect could drive small and confined populations of rare species to extinction. In this paper, we propose a general model for describing spatio-temporal dynamics characterized by demographic Allee growth. In this approach, we include the combined contribution of stochasticity and spatial processes, typically dispersal, which is scarcely explored in the literature. The model is formulated in a reaction-diffusion framework, where the dynamics is regulated by a typical Allee–dispersal evolution and the resilience to white noise is probed at different perturbation amplitudes. Preliminary results show that dispersal processes can compensate random fluctuations to favor the stabilization of the species establishment. [Copyright &y& Elsevier]