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Vegetation is often classified through phytosociology, which defines floristically and ecologically coherent units identified by diagnostic species. Since species- and community-environment relations are regulated by plant functional traits, it is likely that phytosociology has a strong functional underpinning, although the past and current phytosociology does not explicitly tackle this issue. Here we provide an analysis of functional traits of 221 woody species from Northern Italy, diagnostic of 21 European woody vegetation classes (including alien dominated ones). We assessed whether the functional space occupied by selected species corresponds to the physiognomy and ecology of the vegetation they represent, and whether this could help to evaluate major threats, such as invasion by alien species. For each species we collected from Authors’ datasets leaf trait data (leaf area, specific leaf area, leaf dry matter content, carbon to nitrogen ratio, leaf nitrogen content) and whole plant (plant height, seed mass) traits, and calculated Competitor, Stress-tolerant, Ruderal (CSR) scores. We identified the multidimensional functional trait space of diagnostic species and clustered classes according to their scores in the functional space, to check whether their physiognomy was coherently represented and mirrored in the CSR space. Lastly, we tested for differences between native and neophyte species and their overlap with classes. Diagnostic species mirrored the global spectrum of plant form and function, and classes showed a functional pattern coherent with their physiognomy and ecology. Evergreen dominated classes showed a similar convergence toward conservative characteristics and the stress-tolerant strategy, as opposed to deciduous forest classes that showed a tendency toward the competitive strategy. None of the classes showed a marked ruderal strategy, thus abiotic stress and biotic competition are the main ecological drivers affecting woody vegetation. Neophyte woody species exhibited relatively more competitive strategies compared to natives, and their invasion could be facilitated in resource-limited or mildly disturbed environments, should climate warming or increased nutrient availability occur. We demonstrated that plant traits and CSR strategies of woody diagnostic species reliably indicate the structure and functions of the phytosociological classes they represent, opening the way to the development of a “functional phytosociology”.

This study aims to characterize saline habitats of the Tuscan coast based on the Natura 2000 Habitats Directive 92/43/ECC. These habitats include Atlantic salt meadows (1330), Mediterranean salt meadows (1410) Mediterranean and thermo-Atlantic halophilous scrubs (1420), and Mediterranean salt steppes (1510). We compiled vegetation data from a total of 418 plots carried out during our own fieldwork (N = 157) and published scientific literature (N = 261). We performed a Linear Discriminant Analysis to associate species to habitats and used the phi coefficient of association to identify diagnostic species of each habitat. For each habitat, we provide a regional syntaxonomic framework, constant species, cover coefficients, diagnostic species (phi) and “typical species”. We identified groups of species, that we called “local assembly of typical species”, composed by species with a phi coefficient > 20 and/or a cover coefficient > 50 that can be used to identify the habitats and to monitor their conservation status at the local level. This study revealed differences in the “local assembly of typical species” among habitats, characterized by fewer species in habitats 1420 and 1510, and many species in habitats 1410 and 1310. Our results showed that the habitat 1510 was recognizable only for the high cover value of Limonium narbonense and, at least in Tuscany, its syntaxonomic attribution to the order Limonietalia is uncertain. We tested this approach only for a few habitats, but a broader applicability based on other habitats is desirable.

International audience; Habitat degradation and fragmentation are recognized as major causes of biodiversity loss, and effective management to conserve habitats is highly dependent on our ability to assess their conservation status. In this study we introduce a new index (VCS, for vegetation conservation status) to assess the conservation status of plant communities, which reflect the identity of habitat types. The VCS index is based on the same probabilistic approach than the classical Simpson's diversity index, but uses the concept of species pools to integrate the influence of ‘typical’ and ‘non-typical’ species on habitat conservation status. In addition to the effect of species identity, this index also allows the detection of change in conservation status because of variation in species-abundance distribution. As an example we applied the VCS index to two heathland habitats in French Brittany and we compared the values provided by the index to qualitative assessments by heathland experts. We also compared the performance of the VCS index against three other indices: species richness, species diversity and a more recent index of ‘favourable conservation status’. Among the four indices tested, the VCS index was the most effective in assessing the vegetation conservation status when compared against qualitative assessment by heathland experts. Moreover the VCS index, coupled with variance partitioning methods, allowed to quantify the contribution of expected causes of habitat degradation. This study demonstrates that the use of habitat-specific species pools to distinguish between typical and non-typical species, as well as the consideration of species abundances, are critical for an accurate assessment of the vegetation conservation status. The VCS index should therefore be a valuable tool for both managers and researchers involved in habitat conservation.

Biodiversity conservation often requires a landscape perspective. When establishing the Natura 2000 (N2k) network, the effectiveness of the sites and the influence of the surrounding landscapes for species of interest was often disregarded. We analyzed the effectiveness of N2k sites in Sweden for three forest bird species of conservation interest in the European boreal landscapes: lesser spotted woodpecker (LSW), Siberian jay (SJ) and hazel grouse (HG). Our objectives were to: 1) quantify effective suitable habitat area in N2k sites with and without consideration of the adjoining landscapes; 2) examine effective habitat area within N2k sites along the north-south vegetation gradient 3) analyze functionality of N2k sites and assess how forests outside the sites affect habitat suitability inside N2k. GISbased habitat suitability index models were applied to calculate the amount of effective habitat within and outside N2k sites. N2k sites contributed with 10% (HG), 13% (SJ) and 51% (LSW) suitable habitat identified in Sweden. Functionality of forest environments as habitat was higher inside N2k sites for LSW within all vegetation zones, and for SJ in the Alpine and Middle Boreal zones; for HG habitat outside the sites was more functional in all zones accept Alpine and Middle Boreal. The majority of N2k sites were of quite small size (

The importance of heathlands as habitats for plants and thus for nature conservation is recognized by European Directive 92/43 (Habitats Directive). However, heathlands are threatened by habitat lo...

The article 17 of the 92/43/EEC Habitats Directive imposes to the Members States to produce periodic reports (every 6 years) on the conservation status of habitats and species at national level. In this context, in view of preparing the 4th National Report, the Italian National Institute for Environmental Protection and Research (ISPRA) drafted the national guidelines for habitats monitoring, focusing on data collection at site level. The intention of this paper is to provide an overview about the development, in Italy, on Habitat types monitoring methodologies, in particular detailing the current state-of-the-art for the parameter structure and functions, which is the most controversial among those required by the Habitats Directive for the assessment of conservation status. The paper concludes that, although habitat types monitoring programs could be carried out using individual species of fauna and/or flora, vegetation surveys represent the best choice as it allows to collect standardised and objective data, useful for the definition of more specific indicators, first of all the presence and abundance of typical species.