Daniele Viciani

Conservation assessment of the endemic plants of the Tuscan Archipelago, Italy.

The Mediterranean islands support a rich diversity of flora, with a high percentage of endemic species. We used the IUCN categories and criteria to assess the conservation status of 16 endemic plant taxa (species and subspecies) of the Tuscan Archipelago, based on data collected during field surveys over 4 years. Our data were sufficient to use criteria B, C and D in our assessment. We used criterion B in the assessment of all 16 taxa, criterion C for four taxa, criterion D for 11 taxa and criteria B, C and D for three taxa, Centaurea gymnocarpa, Limonium doriae and Silene capraria . According to our results L. doriae, Romulea insularis and S. capraria are categorized as Critically Endangered and therefore require immediate conservation measures; eight taxa are categorized as Endangered, two as Vulnerable and three as Near Threatened. Compared to earlier assessments, eight species are recategorized with a higher degree of threat, two species are recategorized with a lower degree of threat, five are unchanged, and one species is assessed for the first time. Based on the IUCN categorization our results show that all the endemic species of the Tuscan Archipelago are directly and/or indirectly threatened by human activities, such as tourism and agriculture, and invasive species of plants and animals. The Tuscan Archipelago National Park is responsible for the conservation of all endemic species in the area.

Acidophytic shrublands in the north-west of the Italian peninsula: Ecology, chorology and syntaxonomy

Abstract The shrublands growing on siliceous and/or calcium-poor substrata of the hilly and mountainous areas of north-western and central Italy were studied. This secondary vegetation is dominated by several acidophilous shrubs like Ulex europaeus, Cytisus scoparius, Erica arborea, E. scoparia and Calluna vulgaris. The synecology, synchorology and syntaxonomy of this vegetation was studied using multivariate methods, and discussed in comparison with similar types described in other zones of the Italian peninsula. Two new subassociations are proposed here: Erico arboreae-Arbutetum unedonis genistetosum germanicae and Calluno-Sarothamnetum ericetosum scopariae. Calluno-Sarothamnetum is typified; the Sarothamnion alliance is discussed and referred to Cytisetea scopario-striati. The presence of Calluno-Ulicetea and Cytisetea scopario-striati classes is discussed, and a syntaxonomical scheme is proposed.

Mapping patterns of ferns species richness through the use of herbarium data

This paper aims to analyse the spatial patterns of sampling effort and species richness of pteridophyte in a well-investigated region as Tuscany, Italy, by using data stored from a geodatabase storing information on the specimens preserved in the main herbaria of the region. A total of 6,905 records about pteridophyte specimens were extracted from the geodatabase, and 5,638 of such specimens were studied through the use of spatial statistical techniques. The data about the sampling effort and species richness were analysed in relation to topographical variables to assess any significant relationship. Specimen-based rarefaction techniques were used to compare areas with different number of detected species. The analysis of the sampling effort data showed a nonhomogeneous distribution of herbarium data, with some areas being intensively sampled and others being almost unsampled. Thus, the geographical distribution of specimens was extremely clustered. The comparison across geographical areas through specimen-based rarefaction curves showed great differences in species richness and sampling completeness. The analysis of the residuals of species–area relationships evidenced that the distance to water bodies was the only significant topographical variable in controlling species diversity.

Long-term monitoring of an invasion process: the case of an isolated small wetland on a Mediterranean Island

Invasions of Typha (cattail) and/or Phragmites (common reed) in wetland ecosystems result in changes in species richness, diversity and composition of vascular plants. These invasions are particularly harmful in lakes where threatened species and/or communities are found. The spread of two species of Typha (T. angustifolia and T. latifolia) and of Phragmites australis in the Stagnone Lake, on Capraia Island (Tuscan Archipelago — Mediterranean sea) was studied. We report this progressive invasion, documented by means of a series of vegetation maps (1991, 1995, 1998 and 2009). The expansion rate of the three invasive helophytes and the shrinking of the aquatic communities were studied using a GIS system. The impact of the spread of these three species on the floristic characteristics of the plant communities and the lake vegetation in general, was analysed by means of 15 plots of 1 m2 in 2000 and in 2009. Statistical analysis of the two series shows a significant change in the floristic composition of the communities as a result of the invasion process. Many important groups of species, such as many aquatic species, decrease in number and in cover value.

Detailed Natura 2000 and CORINE Biotopes habitat maps of the island of Elba (Tuscan Archipelago, Italy)

The island of Elba (Tuscan Archipelago, Italy) Natura 2000 habitat map (1:25,000) and the CORINE Biotopes habitat map (1:25,000) were derived from the phytosociological map of Elba integrated with recent studies and field knowledge of the vegetation units. Conventional geographical information system queries were used to manage and select the spatial information. For each map polygon, the following attributes were assigned: (i) habitat typology and (ii) percentage cover of each habitat type. Where multiple habitat types were associated with the same polygon, the percentage cover of each habitat type was estimated. A total of 27 Natura 2000 habitat types and 58 CORINE Biotopes habitat types were identified, these being distributed in single and/or multiple typological units. Distribution and covers of the different habitat types are discussed. The usefulness of this kind of map for monitoring and managing conservation actions is discussed.

Genetic structure of Linaria capraria Mill. (Plantaginaceae) and endemic species of the Tuscan Archipelago (central Mediterranean)

This study, based on inter-simple sequence repeats in 14 populations of Linaria capraria, shows that genetic diversity at the species level is 0.21 and represents 58% of total variance, whereas the level of intrapopulational genetic diversity is 0.07 and represents 42% of total variance. Gene flow is absent between populations from the same island. On the basis of analysis of molecular variance, three centers of genetic diversity were found: Elba and Pianosa, Montecristo, and Capraia; these correspond to the group of islands that remained isolated during the Würm marine regression. A mean proportion of species-level diversity resides among populations, so we hypothesize that the species has a mixed reproductive system that lies somewhere between obligate outcrossing and obligate selfing. The most genetically diverse populations live in natural and well-isolated rocky habitats that seem to have no particular intervention requirements for conservation but the entire system of populations of this endemic species should be preserved.

Habitat conservation prioritization: A floristic approach applied to a Mediterranean wetland network

Abstract The importance of plant communities for conservation purposes is recognized in their inclusion in the “Habitat Directive” (92/43 EEC), that relates habitat types to plant community syntaxonomic units. However, habitat definitions in the Habitat Directive lead to several inaccuracies in local habitat characterization. Several wetland plant communities (and their corresponding habitats), rare in the Mediterranean basin, are not included in the Habitat Directive. This study proposes criteria for assessing the conservation importance of habitats. It deals with plant community types at the alliance level, as promising units for setting conservation priorities. The principle criteria considered as drivers for setting alliance conservation values are the distribution and abundance of plant species of conservation interest and their fidelity to a plant community. Multivariate methods were used, and a quantitative floristic index of alliance conservation priority was created. This procedure was applied to an important wetland in central Italy. Results emphasize: (i) high conservation values of some alliances not listed in the Habitat Directive, confirming various gaps in the current conservation law affecting Mediterranean wetlands; (ii) that habitats widely distributed in other biogeographical areas, may greatly underestimate their conservation importance in Mediterranean region; (iii) need to consider regional peculiarities when setting conservation priorities.

Gap analysis comparing protected areas with potential natural vegetation in Tuscany (Italy) and a GIS procedure to bridge the gaps

The aim was to compare the protected area (PA) network in Tuscany, Italy, with the areas referenced to different types of potential natural vegetation (PNV), to determine whether they are adequately represented for plant and habitat conservation purposes. For PNV, an existing but slightly updated and modified Italian Vegetation Series (VS) map was used. Each VS type corresponds to vegetation complexes that live under homogeneous environmental conditions and can each be considered an ecological land unit at the working scale employed here. Using GIS techniques, the geographic layers of PAs and VS were processed with spatial intersection to extract and quantify the VS contained within the boundaries of PAs. As a minimum conservation goal, we used the widely accepted 10% target threshold. It was found that, even though Tuscan PAs covered almost 20% of the total land surface, 94% of VS types resulted to be included in PAs with a percentage of at least 10% of their total area. The survey shows that the VS with the higher degree of inclusion in PAs are distributed in the Mediterranean Tuscany (coast and Tuscan Archipelago) and in some inner areas such as Apuan region, northern Apennines, Amiata Mt. and Farma-Merse Valley. Two VS types must be considered under-protected (i.e. contained in an existing PA network with percentages < 10%). We propose a simple GIS procedure based on certain priority assumptions: (a) existing PAs should be enlarged rather than new ones created and (b) their naturalness taken into account. This procedure produces a suitability map useful for identifying the best areas in which a local administration might look for solutions to bridge the gaps.

Habitat conservation in Italy: the state of the art in the light of the first European Red List of Terrestrial and Freshwater Habitats

The importance of taking into account ecosystems, plant communities and habitats for the development of biodiversity conservation strategies is increasingly acknowledged. Recently, the first ever European Red List of Habitats was produced, which provided an evaluation of the extinction risk of EUNIS-based natural and semi-natural habitats in Europe. As assessment unit, it used the habitat intended as a plant community, thus representing a landmark for the role of vegetation science in nature conservation. In the present paper, the results of the European Red List of Habitats are analyzed at the national scale with specific reference to the terrestrial and freshwater habitat types occurring in Italy. More than three-quarters of the assessed European habitat types were recognized for the Italian territory. The distribution of the threat categories reflects approximately the situation at the EU28 level. About 35% of the assessed habitat types are referred to a threat category; no critically endangered habitat is present in Italy. The most frequently used criteria are those related to a reduction in quantity. Some critical issues arising from the analyses are discussed. In particular, the presence of knowledge gaps is pointed out, with remarkable reference to the poor availability of spatial and quantitative data, severely affecting the application of the criteria adopted for the assessment. Descriptions of habitat types from Italy are reported, some of which are representative, emblematic or even exclusive to the Italian territory. The outcomes of the analysis represent the starting point for the future development of a national-scale Red List of Habitats. Results also emphasized how habitat types with a too broad definition pose a limit to a proper evaluation of the regional biogeographic variability, often very high in Italy, with local floristic and phytocoenotic peculiarities which do not find room in the adopted European typology. This is the reason why the development of national subtypes stands as a necessary step for the development of a realistic and effective assessment at the national scale.

Predicting risk of invasion in a Mediterranean island using niche modelling and valuable biota

Abstract Invasion by alien species is nowadays considered as one of the major threats to biodiversity. Thus, the identification of the areas exposed to a greater risk of invasion represents a priority for management purpose, especially in presence of habitats worthy of conservation. This paper aims to propose a method to produce a map of risk of invasion, merging together the threat of invasion by invasive plants and the distribution of habitats with high conservation value, on the case study of the Island of Elba (Tuscan Archipelago). We modelled the potential distribution of six particularly harmful invasive plants and merged these distributions into a map of threat of invasion. This map was overlapped to the map of density of Natura2000 habitats, finally obtaining a map of risk of invasion. According to our analyses, the potential distribution of the invasive species resulted highly influenced by human-related factors. The habitats more at risk are those closer to streets and anthropic habitats, which are more likely to be colonized by the invasive species we studied. We identified some rare habitats which are strongly endangered, highlighting that around 20% of the surface of the Island is exposed to some level of risk of invasion.