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Sustainable Forest Management (SFM) indicators consider the main ecological and socioeconomic functions of forests but do not currently include some key groups widely adopted to assess the effects ...

In light of the hypothesis that different authors, who have access to the same information and tools, can give different interpretations of the same reality, namely the vascular plants, existing within a determinate geographic boundary, this research aims to verify how and to what extent these differences can affect a checklist, and what critical issues and positive effects may arise in them. To this purpose, we compared two different checklists which were developed approximately in the same period for the same geographic area, the island of Sardinia (Italy). The results show that checklists of the same area can differ in quantitative terms, establishing a different value of floristic richness. Moreover, they can differ in qualitative terms due to the different approach adopted by the authors concerning nomenclature, taxonomy, and interpretation, delimitation, and circumscription of taxa. These discrepancies may have positive side effects as they offer insights for critical reviews and further investigation.

Aims: i) To disentangle the global patterns of native and alien plant diversity on coastal sand dune ecosystems across habitats and floristic kingdoms, ii) to determine the main drivers of variation in species richness in native and alien species in these endangered ecosystems, and iii) to test for an interaction between spatial scale and native‐alien richness patterns, as predicted by the invasion paradox. Location: Global. Methods: We collated a dataset of 14,841 vegetation plots in coastal sand dune ecosystems from around the world. Generalized Linear Models (GLMs) and Generalized Linear Mixed Models (GLMMs) were used to assess the patterns and main ecological determinants underlying native and alien species richness. Variation partitioning revealed the relative importance of environmental and anthropogenic variables. Results: GLMs revealed strong differences among both habitats and floristic kingdoms in the number of native and alien species. Specifically, native species richness increased along the sea‐inland gradient and was higher in the Cape and Paleotropical kingdoms. In contrast, alien species richness was relatively similar across habitats and kingdoms, though some differences were detected. There were strong differences between the drivers of native and alien richness; anthropogenic factors such as Gross Domestic Product were positively associated with alien richness whereas native richness was more strongly related to environmental factors. Furthermore, we found a weak support for an invasion paradox effect. Conclusions: Our results revealed the complexity of causal processes underpinning coastal sand dune plant biodiversity and highlight the importance of considering native and alien species separately. Recognition of these differences while researching variation in biodiversity patterns and processes at multiple spatial scales will lead to a better mechanistic understanding of the causes of invasion worldwide, and in coastal ecosystems in particular, allowing the development of more focused control and management measures.

This study aimed to test if differences in soil salinity, plant richness and diversity were significantly affected by habitat, site and distance from the seashore at three sandy and three rocky coastal sites in north-western Sardinia. Each site has been divided into three belts placed at an equal distance of 50 m from the shoreline. We measured soil salinity using a probe and vascular plants richness and diversity using linear transects at all sites. Average soil salinity varied from 0.115 g/l to 0.180 g/l; it was higher in the rocky habitats than in the sandy ones. A total of 21 species were found per transect/site at the rocky sites and 30 species per transect/site at the sandy sites, with an average of Shannon and Weaver's Diversity Index of 1.8 per each belt at each site. These data confirm that, also in the Mediterranean islands, there are coastal gradients of soil salinity from the seashore to inland areas and that also vascular plant richness and diversity are influenced by the distance from the sea. Soil salinity was strongly affected by the type of habitat, being average at the rocky coasts and negligible at the sandy shores. The site effect was not significant for both soil salinity and plant richness and diversity.

The Mediterranean Basin is a biodiversity hotspot, where islands play a key role because of their high biological diversity, degree of endemicity and human pressure. One of these islands, Sardinia, is a good evolutionary laboratory, especially for the study of complex genera, such as Centaurea. In particular, endemic species of Centaurea sect. Centaurea from Sardinia provides an interesting case study of plant evolution on continental islands. We attempted to clarify the processes leading to the diversification of Centaurea species on Sardinia using bi-parentally inherited nuclear markers and maternally inherited plastid markers. Our plastid results revealed the presence of five lineages of sect. Centaurea on the island. Three of them were defined as three species: C. ferulacea, C. filiformis and C. horrida. The other two lineages highlighted the complex evolutionary history of the two polyploids C. corensis and C. magistrorum. Multiple colonization events from the mainland involving the C. deusta and C. paniculata lineages among others, have led to the diversity of sect. Centaurea on Sardinia. One colonization event likely followed a southern path via the land connection between the mainland, the Calabrian Plate and Sardinia. A second pathway likely followed a northern connection, probably through the Tuscan Archipelago. Implications of these findings on conservation efforts for Centaurea endemics on Sardinia are also discussed., Financial support from the Generalitat de Catalunya, Ajuts a Grups de Recerca Consolidats 2014-SGR514-GREB and 2017-SGR1116 and from the Spanish Ministry of Science and Innovation, Projects CGL2007-60781/BOS and CGL2010-18631/BOS for A. S. and N. G-J is gratefully acknowledged. This study was also supported by the Regione Autonoma della Sardegna, LR 7/2007 – PO Sardegna FSE 2007–2013, with the grant no. CRP2_474 for R.F. and E.F, Introduction Materials and methods Results Discussion Supporting information Acknowledgments References

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 p...

Background and aims – Exploring the role of mammalian carnivores as seed dispersers in Mediterranean environments is crucial for understanding biotic interactions and preserving mutualistic networks in areas with high biodiversity. We examine the potential role of the Sardinian fox ( Vulpes vulpes subsp. ichnusae ) as a seed-disperser of two juniper species ( Juniperus phoenicea subsp. turbinata and J. oxycedrus subsp. macrocarpa ) in Mediterranean coastal environments.Methods – Observational and manipulative experiments were conducted in five coastal sites in north-western Sardinia (Italy) between 2010 and 2013.Key results – We found that Sardinian fox actively disperses seeds of J. phoenicea subsp. turbinata, whereas no evidence was obtained for the fox dispersing seeds of J. oxycedrus subsp. macrocarpa. Fox scat contained, on average, 73–86 J. phoenicea subsp. turbinata seeds, accounting 16.3–17.8 % of the average dung weight. The role of Sardinian fox as a primary disperser of J. phoenicea subsp. turbinata is by directly dispersing juniper seeds (via defecation) to a specific microhabitat (i.e. 80–90 % of dung was released on dwarf plants, mainly Helichrysum italicum subsp. microphyllum ), which positively affected the survival of emerged seedlings). We quantified that fox dispersed 30 to 100 seeds per day per hectare (3 500–10 500 seeds per hectare in one winter season).Conclusions – We reported that Sardinian fox is a direct disperser of J. phoenicea subsp. turbinata, thus playing a major role in secondary successional dynamics in Mediterranean coastal environments. Evolutionary implications are discussed, in that the positive interaction between Sardinian fox and J. phoenicea subsp. turbinata could be recent, following the introduction of fox to the Tyrrhenian islands during the 7 th –6 th millennium BC.

Italy is among the European countries with the greatest plant diversity due to both a great environmental heterogeneity and a long history of man–environment interactions. Trait-based approaches to ecological studies have developed greatly over recent decades worldwide, although several issues concerning the relationships between plant functional traits and the environment still lack sufficient empirical evaluation. To draw insights on the association between plant functional traits and direct and indirect human and natural pressures on the environmental drivers, this article summarizes the existing knowledge on this topic by reviewing the results of studies performed in Italy adopting a functional trait approach on vascular plants, bryophytes and lichens. Although we recorded trait measurements for 1418 taxa, our review highlighted some major gaps in plant traits knowledge: Mediterranean ecosystems are poorly represented; traits related to belowground organs are still overlooked; traits measurements for bryophytes and lichens are lacking. Finally, intraspecific variation has been little studied at community level so far. We conclude by highlighting the need for approaches evaluating trait–environment relationship at large spatial and temporal scales and the need of a more effective contribution to online databases to tie more firmly Italian researchers to international scientific networks on plant traits.

Background: Hybridisation is a key driver of plant speciation, and understanding ongoing hybridisation provides insights into the underlying process(es). We studied a hybrid complex in Mediterranean Cyclamen between the common C. repandum and rare C. balearicum in Sardinia. Aims: We analysed variation in the frequency and morphology of different floral types to assess the degree of hybridisation and analysed the ecological niche to identify factors that are likely to influence the maintenance of hybrid populations. Methods: We recorded the frequency of the different flower colour types in 45 populations and measured floral traits in 10 of them. We characterised the spatial extent and climatic niche of this hybrid complex. We analysed floral type variation in four traits (flower size, style and anther length, herkogamy) along a hybridisation gradient. Results: Hybrid populations occupy a wide area (ca. 1000 km2) on the north-west coast of the island. Sites dominated by hybrid floral types are ecologically marginal for the common parent. The C. repandum-like type is present in all populations and shows a decrease in style and anther lengths and herkogamy in populations containing a greater proportion of hybrids. Conclusions: This hybrid complex provides an ideal case of reproductive isolation owing to the differences in the ecological niche where different floral types are found.

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 ...

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.

Bioclimatology deals with the interrelation between climate and living organisms, in particular, plants and plant communities, considering the main climate variables that are relevant for species distribution. In this context spatial interpolation of monthly temperature and precipitation data using 203 rain gauges and 68 temperature gauges for Sardinia (Italy) was undertaken. As interpolation technique, we used regression kriging which combines multiple linear regression (MLR) with ordinary kriging of the residuals. MLR procedures include as independent variables: altitude, latitude, longitude, coast distance and a topographic factor of relative elevation. Elevation data were obtained from digital elevation model at 40 m resolution. Following the approach of the Worldwide Bioclimatic Classification System, a bioclimatic diagnosis of the entire territory was derived using map algebra calculations of the bioclimatic indices proposed by Rivas-Martínez et al. [(2011). Worldwide Bioclimatic classification system. Global Geobotany, 1, 1–638]. Two macrobioclimates (Mediterranean pluviseasonal oceanic and Temperate oceanic), one macrobioclimatic variant (Submediterranean), and four classes of continentality (from weak semihyperoceanic to weak semicontinental), eight thermotypic horizons (from lower thermomediterranean to upper supratemperate) and seven ombrotypic horizons (from lower dry to lower hyperhumid) were identified, resulting in a combination of 43 isobioclimates. The resulting map represents a useful environmental stratum, for regional planning, ecological modeling and biodiversity conservation.

Depensation in a population growth rate, well-known as Allee effect , has dramatic implications for the dynamics and conservation of small or sparse populations, as it can drive low-density populations to extinction when their demographic size is below a critical threshold. Although rarely detected, depensation effects are believed to be common in nature. Here we present experimental evidence for Allee effect in one Mediterranean endemic plant: Anchusa sardoa . Depensation in the population growth rate is demonstrated through a density-based approach by showing the fingerprinting relationship which ties the population density to its per capita growth rate ( pgr ) during specific stages of the plant life-cycle. The pgr –density plots derived from observational data qualitatively compare with a general 2nd order polynomial function which features one of the peculiar trends underlying an Allee mechanism. We found strong evidence for depensation in the seedling and sapling classes, whereas no-depensation effect could be clearly observed in the adult classes. We also point out a characteristic demographic structure of A. sardoa (i.e. number of juveniles > number of adults) which reflects a not common life strategy with respect to Mediterranean endemic plants. By combining dynamical and demographic information, the results of this study suggest a possible scenario by which A. sardoa population could go extinct, and are discussed in the context of the increasing mass tourism in Mediterranean coastal environments.

The aims of this paper were (i) to define how contrasting land uses affected plant biodiversity in Mediterranean agro-silvo-pastoral-systems across a gradient of disturbance regimes: cork oak forests, secondary grasslands, hay crops, grass covered vineyards, tilled vineyards; (ii) to determine whether these patterns mirrored those of below-ground microorganisms and whether the components of γ-diversity followed a similar model. The disturbance regimes affected plant assemblage composition. Species richness decreased with increasing land use intensity, the Shannon index showed the highest values in grasslands and hay crops. Plant assemblage composition patterns mirrored those of Basidiomycota and Ascomycota. Richness in Basidiomycota, denitrifying bacteria and microbial biomass showed the same trend as that observed for vascular plant richness. The Shannon index pattern of below-ground microorganisms was different from that of plants. The plant γ-diversity component model weakly mirrored those of Ascomycota. Patchy diversity patterns suggest that the maintenance of contrasting land uses associated with different productions typical of agro-silvo-pastoral-systems can guarantee the conservation of biodiversity.

With the consensus that human activities are leading to dangerous interference in Earth’s climate, there has been growing policy pressure for clear quantification and attribution of the resulting biological impacts. Despite the exceptional diversity in the Mediterranean biome, largely due to the number of rare and endemic plant species, the effect of future climate change on present Mediterranean plant species has only been examined in a few studies. In this study we presented an analysis of the potential effects of climate change on 22 plant species whose range is restricted to central-northern Mediterranean region. We used species distribution modelling to test whether projected climate change may affect the current suitability of species’ habitat; to evaluate possible future threats due to climate change; and to test any relationship between extinction risk and ecological and life-history predictors. The studied species were predicted to lose some 50% of their current range by 2020. Similarly, the probability of occurrence in known localities was predicted to drop drastically by 2020. Our results support a relationship between biological characteristics and range contractions. Although the Mediterranean species were projected to lose a lower amount of habitat than Alpine ones, species with restricted geographic range seem to be more prone to climate change effects than widespread ones. Our results emphasize the need for immediate monitoring and conservation actions and suggest that rare species might be useful for monitoring the conservation status of habitat in relationship to the effects of global warming in the Mediterranean region.

44 p. -- graf., mapas -- Post-print del articulo publicado en Taxon. Version revisada y corregida.

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.

Molecular approaches have greatly increased the number of confirmed homoploid hybrids, which suggests that the frequency of this phenomenon was underestimated in the past because it was much more difficult to detect than allopolyploidy. Centaurea is a suitable model group for studying homoploid speciation, as hybridization events have been commonly reported for this genus. Based on this, here we study Centaurea × forsythiana, a naturally occurring homoploid hybrid between two Sardinian endemics, C. horrida and C. filiformis, using a molecular approach involving nuclear and plastid markers, to understand the underlying population dynamics between homoploid hybrids and their parents. Our results confirm that C. × forsythiana is a hybrid between the above-mentioned species and define the roles of the parents. Plastid markers point towards C. horrida as the maternal progenitor, and nuclear markers reveal that the other parental species, C. filiformis, is itself an old, stabilized homoploid hybrid related to the C. paniculata complex from the Italian mainland. Homoploid hybrid speciation is discussed and C. × forsythiana and C. filiformis are compared with other similar examples. The study confirms the importance of introgression between parental species mediated by hybrids and its potential implications in conservation. Furthermore, it shows how hybridization studies become even more complex when the parents are themselves of probable hybrid origin. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 175, 453–467.

The collection and organization of distributional data is the first crucial stage of any conservation planning action: therefore the decline in field research has implications in both the systematic, floristic and conservation fields. The aim of this paper is to analyze the effects of data updating on conservation planning and priorities. Focusing on the short time frame ranging from 2006 to 2011, we present a case study showing the rate of increase of collected data (taxa and records) and the consequential effects on the definition of areas of priority interest for plant conservation (Important Plant Areas—IPAs). We gathered data on a total of 193 taxa and 849 records with a mean rate of increase of +97 % for taxa and +166 % for records (2006/2011). This increase caused a positive rate of change in high ranking cells (+78 %) defining IPAs, while the number of low ranking cells and no data cells slightly decreased (−12 and −8 %, respectively). Our results suggest that specific investment to complete the knowledge on the distribution of selected taxa (e.g. 193 taxa represent the 7.5 % of the total vascular flora of Sardinia) would dramatically reduce both the Linnean and Wallacean shortfalls and would allow robust conservation programs to preserve the diversity of the island. Updating the IPAs on a regular basis is a good example of a process that has a low impact as well as a big potential gain especially when field research can only be performed with low intensity and small monetary investments.

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 cr...

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 cors...

11 páginas, 1 tabla, 5 figuras. The final publication is available at www.springerlink.com, [EN] The introduction of alien ungulates is a major threat for the survival of endangered plants, especially in island ecosystems. However, very few studies have investigated the potential damage of large herbivores on plant diversity in Mediterranean protected areas. In this study, we describe the population structure and the long-term dynamics of the main populations of the Sardinian narrow endemic Centaurea horrida Bad. (Asteraceae), by means of permanent plots where individual plants were tagged and monitored through 6 years (2004–2009). We monitored this endangered plant at three sites: two were protected areas where introduced and feral ungulates are present, and the other one was a non-protected site without introduced ungulates. We found that adults and saplings were more abundant at the non-protected site. Through matrix models, we also highlighted that the non-protected population showed the highest population growth rate. Finally, by means of an exclusion experiment for ungulates at one protected site, we demonstrated that herbivores had a negative effect on the survival of seedlings and adult plants, and reduced the stochastic population growth rate. An LTRE analysis showed that differences in the survival, especially of adult individuals, had the highest responsibility in explaining the higher population growth rate when herbivores are excluded. Our study constitutes a clear example on how the protection of alien large herbivores can have opposite effects on the conservation of an endangered plant. Some management options are proposed, and the urgent need of manipulative experiments on species-specific interactions between protected plants and alien herbivore species is invoked., This study was supported by the Regione Autonoma della Sardegna, LR 7/2007–PO Sardegna FSE 2007–2013, with the Grant No. CRP2_474 for RF and EF, and no. CRP3_188 for SP. MBG also got support from a Spanish National Park project (OAPN, REF. 430/211). We thank the Ente Foreste della Sardegna, the Parco Nazionale dell’Asinara and the Parco Regionale di Porto Conte for the technical aid received.

Spatial variability in the structure of a population and in the reproductive traits of the narrow endemic coastal plant thorny knapweed (Centaurea horrida; Asteraceae) was estimated. Variations in the distribution of individuals and reproductive effort were described and quantified at the per-site scale (3 sites, less than 30 kilometers apart) for two habitats (cliff face and cliff plateau) to provide a basis for further investigations of the factors affecting C. horrida performance and to provide information necessary for an effective conservation of this species. Centaurea horrida was considerably more abundant at one site, especially in the cliff plateau, in the contribution of adults. Estimates of spatial variance for each life stage at both habitats revealed that, on the cliff plateau, a much greater variability was found at the per-site scale for classes of saplings and adults of middle size, whereas in the cliff face local (among replicates), spatial variance was higher for all comparisons...

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.

Changes of pasture communities consequent to management practices resulting from land abandonment considerably affect the structure and function of the ecosystem. This study analyses the consequences of grazing abandonment in terms of plant and soil microbial diversity and fertility, on a Mediterranean upland sheep pasture, over a short period (five years). Grazing was experimentally excluded by fencing ten 10×10 m permanent plots within an area that had supported grazing until 2000, by 0.23 sheep ha−1. Plant and soil microbial communities and physicochemical parameters were monitored within the fenced and unfenced control plots, during three sampling times from 2000 (before the fencing) to 2005. Grazing cessation notably altered the floral composition, with an average dissimilarity of 96.7% between the vegetation communities, over five years. No significant change occurred in the control plots that were grazed throughout the sampling period. This work highlighted that, over a short term, the structural change in the specific plant composition affected only the grass species, confirming that grazing favours the small-sized species over the annual species. Further, it was evident that species groups of conservational and phytogeographic interest, like the endemic and Mediterranean-Atlantic species, tended to disappear with pasture abandonment and were substituted by more widespread species throughout the Mediterranean or even the world. Pasture abandonment was accompanied by an increase of soil pH and a decrease in soil organic matter and soil nitrogen. The microbial parameters recorded at three different sampling times revealed a substantial effect of the plant community, or the time of grazing abandonment, on soil microbial abundance and diversity. Considerable importance is given to the consequences of pasture abandonment on the conservation of plant and microbial diversity and on soil fertility.

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...

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 a...

Summary The Mediterranean Basin, possessing 4.3% of all plants of the world, is considered one of the biodiversity hotspots at global scale. Several forms of impact on biodiversity are currently taking place in European Mediterranean countries as a result of the abandonment of traditional extensive production systems in areas of particular value for nature conservation. In this study we investigated the effects of the cessation of agro-sylvo-pastoral activities on Centaurea horrida Badaro, a very rare sea-cliff plant, endemic to North-Western Sardinia (Italy) and listed by the IUCN as vulnerable. In a similar way to other cliff species, Centaurea horrida can expand its range when unsuitable surrounding habitats are disturbed. The analysis of aerial photos indicates that about 88.5% of a surface previously occupied by a Centaurea horrida dwarf community was replaced by juniper scrub over a 50-year period. In the juniper scrub Centaurea horrida density is at present 1/5 of that observed in the dwarf community. The spatial distribution of Centaurea horrida individuals was not random but concentrated in open microhabitats, more abundant in the dwarf community than in the juniper scrub. Juveniles were found mainly on bare soil; this being the only microhabitat where seedling emergence may occur. Furthermore, disturbance had a positive effect on the survival rates of saplings. Our data show that Centaurea horrida is a species that is linked to the initial stages of secondary succession, when patches of bare soil are available, but it is non-competitive with the late-succession species of the juniper scrub. Active management practices to maintain Centaurea horrida populations are therefore proposed and discussed.

Common yew (Taxus baccata L.) stands are recognized as prioritary habitats for biodiversity conservation within the European Union. The effects of browsing on the regeneration capacity and spatial dispersal of T. baccata recruits at the European southern limit of the species in the Mediterranean Basin have been herein studied. The efficacy of T. baccata recruitment has been evaluated at six localities in the Northern Sardinia mountains, which have similar altitude, climate, soil, and vegetation but have different types of uses (three were grazed by livestock and three were not). At each site, five habitats have been identified for T. baccata seed dispersal: reproductive female T. baccata canopy, reproductive female Ilex aquifolium canopy, non-fleshy-fruited tree canopy, fleshy-fruited shrubs, and open areas. The density of seedlings was found to be greater under fleshy-fruited trees (reproductive female T. baccata and I. aquifolium) than under shrubs, whereas the sapling density was higher in shrubby habitats, especially at grazed sites due to the mechanical protection afforded by the spiny shrubs against herbivores. Land use (LU) has been found to be the most important factor in determining the spatial distribution of seedlings and saplings in relation to forest habitats. Although browsers had an ephemeral but positive effect on seed germination through their trampling and the resultant scarification, this process eventually became ineffective as was shown by the occurrence of the lowest density of saplings in those habitats where the density of seedlings was the highest. The ultimate and most important effect of browsing was the sharp decrease in the density of saplings, and their almost complete extinction, in non-shrubby habitats. This study highlights the result that, in Mediterranean ecosystems, browsing constitutes the main negative factor on T. baccata seedling-sapling transition and furthermore confirms the necessity to preserve shrubby patches in the vicinity of reproductive female T. baccata and I. aquifolium to permit the regeneration of T. baccata in the presence of livestock. Moreover, at ungrazed sites, T. baccata is able to colonize non-shrubby shady habitats. The application of different management strategies to ungrazed and grazed sites should therefore be the main direction in the management and preservation of T. baccata stands in the Mediterranean region.

Based on study of the lectotype of Cephaloceraton gymnocarpum Gennari, megaspore ornamentation, and chromosome number analysis of specimens from different Mediterranean areas, it is shown here that Isoetes gymnocarpa (Gennari) A.Braun is a species endemic to Sardinia, Central Italy, Corsica, and Baleares, different from the Mediterranean I. histrix Bory and from the mainly CE Mediterranean I. sicula Tod. (= I. subinermis (Gennari) Cesca & Peruzzi).

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.

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. ...

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.

21 p., tablas, gráf., The Centaurea group is part of the Circum-Mediterranean Clade (CMC) of genus Centaurea subgenus Centaurea, a mainly Mediterranean plant group with more than 200 described species. The group is traditionally split on morphological basis into three sections: Centaurea, Phalolepis and Willkommia. This division, however, is doubtful, especially in light of molecular approaches. In this study we try to resolve this phylogenetic problem and to consolidate the circumscription and delimitation of the entire group against other closely related groups. We analyzed nuclear (internal transcribed spacer of the ribosomal genes) and chloroplast (rpl32-trnL intergenic spacer) DNA regions for most of the described species of the Centaurea group using phylogenetic and network approaches, and we checked the data for recombination. Phylogeny was used to reconstruct the evolution of the lacerate-membranaceous bract appendages using parsimony. The magnitude of incomplete lineage sorting was tested estimating the effective population sizes. Molecular dating was performed using a Bayesian approach, and the ancestral area reconstruction was conducted using the Dispersal–Extinction–Cladogenesis method. Monophyly of the Centaurea group is confirmed if a few species are removed. Our results do not support the traditional sectional division. There is a high incongruence between the two markers and between genetic data and morphology. However, there is a clear relation between geography and the structure of the molecular data. Diversification in the Centaurea group mainly took place during the Pliocene and Pleistocene. The ancestral area infered for the Circum-Mediterranean Clade of Centaurea is the Eastern Mediterranean, whereas for the Centaurea group it is most likely NW-Africa. The large incongruencies, which hamper phylogenetic reconstruction, are probably the result of introgression, even though the presence of incomplete lineage sorting as an additional factor cannot be ruled out. Convergent evolution of morphological traits may have led to incongruence between morphology-based, traditional systematics and molecular results. Our results also cast major doubts about current species delimitation., Financial support from the Spanish Ministry of Science and Innovation (Projects CGL2007-60781/BOS and CGL2010-18631) and the Generalitat de Catalunya (Ajuts a Grups de Recerca Consolidats 2009/SGR/00439) is gratefully acknowledged. AH benefited from a predoctoral grant of the JAE program of the CSIC. The collection of Turkish species was funded by the BAP (Scientific Researching Projects of Selçuk University) project with number 06401023.

3 p., 1 fot., Two individuals morphologically intermediate between Centaurea horrida Badarò (1824: 367) and C. filiformis Viviani (1825: 6) were collected by Charles Immanuel Forsyth Major on 26 May 1885 at Tavolara Islet, Italy (FI!): these samples were published by Fiori (1904) and later reported in Arrigoni (1972) as two different hybrids: “C. superfiliformis × horrida Levier” and “C. superhorrida × filiformis Levier”. As annotated on the label by Emile Levier, the material deposited in FI shows that the morphology of the two hybrids is very different and only the one named by Fiori as “C. superfiliformis × horrida Levier” was labelled as C. forsythiana Levier (Fig. 1). This sample is morphologically similar to the individuals of a hybrid population we discovered in the same site in the Tavolara Islet (Timone), on limestone, as reported by Fiori (1904). The hybrid named “C. superhorrida × filiformis Levier” by Fiori (1904) was collected by Forsyth Major in a different site (Bocchetta) on granite, and has never been recollected afterwards. For the matter of this note, this is not a problem since, according to Article H.4.1 of the International Code of Nomenclature (McNeill et al. 2012), all the hybrid variants originated from the same parental species, as far as considered nothotaxa (Art. H.3.1), should bear the same name., This study was supported by the Regione Autonoma della Sardegna, LR 7/2007–PO Sardegna FSE 2007–2013, with the grant no. CRP2 474 for all authors and no. CRP3 188 for SP.

Studies over the last two decades demonstrate that hybridization has played an integral role in the evolution of several sections of the genus Centaurea. Nevertheless, natural hybridization between narrow Mediterranean endemic Centaurea species has not been documented as yet. A population of fertile Centaurea individuals exhibiting intermediate morphological traits between two Sardinian narrow endemics, C. horrida and C. filiformis, was identified at the Tavolara Islet (Sardinia, Italy). Intermediate leaf length and head width characterized this population, suggesting its hybrid origin. The putative hybrid population was structured (i.e., composed of seedlings, saplings and adult individuals) and had a relatively high levels of seed production. The number of chromosomes was identical to that of the proposed progenitors (2n = 18). Genotyping at five microsatellite loci showed that the putative hybrid possessed several alleles in common with the proposed parental species and intermediate values of genetic differentiation, as indicated by both FST and RST, between C. horrida and C. filiformis. We therefore conclude that the studied intermediate population is of hybrid origin, and discuss possible mechanisms of its reproductive isolation from the parental species, potential re-introgression, and evolutionary implications of this hybridization.

† Background and Aims The Mediterranean region is of prime importance to biodiversity at a global level, mainly due to the abundance of endemic plant species. However, information about these species is still scarce, especially at the genetic level. In this paper the first assessment is reported of the genetic structure of Centaurea horrida (Asteraceae), an endemic, sea-cliff-dwelling plant from Sardinia. † Methods The study was conducted on seven populations covering the entire natural range of the species by means of SSR (microsatellite) markers. † Key Results A considerable amount of genetic variation was found (average He ¼ 0.603‐0.854), together with a medium-high differentiation among populations, as estimated both by FST (0.123) and RST (0.158). Both Bayesian analysis and AMOVAwere employed to detect genetic structuring in this species. The results suggest that the origins of the current populations of C. horrida lie in two gene pools. † Conclusions Despite the restricted range, C. horrida displays high levels of genetic diversity, structured in such a way that three management units could be deemed viable for its conservation. The protected status of the species will probably suffice to prevent the impoverishment of its genetic resources.

This paper deals with the anatomical and histological study of a silicified specimen of a palm consisting of a part of the trunk surrounded by roots. The sample comes from the Lower Miocene of North West Sardinia. The comparison with fossil species and exsting species leads to the conclusion that the specimen belongs to a new fossil species closely related to Chamaerops humilis L., widespread throughout the Mediterranean area. Paleo-environmental considerations confirm the presence in Sardinia, in the epoch in question, of formations of Mediterranean forest corresponding in part to forest existing in North Africa today.

Centaurea corensis, a new species of Sardinia is here described. The relationships among the closely related species C. alba L. and C. deusta Ten. are also discussed.