Dario Cusimano

Phytosociological survey vegetation map of Sicily (Mediterranean region)

ABSTRACT We present the results of a study aimed at developing a vegetation map of Sicily (Italy) including the smaller circum-Sicilian islands, for an area of approximately 25,703 km2. The work is a synthesis of studies carried out in accordance with the survey methodology of phytosociology in the last 40 years over the whole study area. The vegetation map of Sicily was compiled in a Geographical Information Systems (GIS) environment, in order to produce a cartographic representation at a scale of 1:10,000 (reduced to a scale of 1:250,000). The physiognomic-structural characteristics of the plant landscape of Sicily are analyzed, providing a general and, at the same time, detailed overview of the phytocoenotic aspects represented on the territory, as well as of the relative bibliographic references. At the reference scale, 36 types are represented, 16 of which are related to zonal vegetation (Mediterranean maquis, Quercus ilex woods, Quercus suber woods, Castanea sativa woods, Quercus pubescens deciduous woods, mesophilous deciduous woods, Fagus sylvatica woods, Betula aetnensis woods, woods dominated by woody gymnosperms, forest edge shrubs, orophilous pulvinate shrubs, shrublands and garrigues, Ampelodesmos mauritanicus grasslands, mesophilous and sub-hygrophilous grasslands and pastures), 11 are related to azonal vegetation (riparian, psammophilous herbaceous, chasmo-halophitic, etc.) and 9 are related to anthropogenic vegetation (arable lands and extensive herbaceous crops, vineyards, olive groves and dry cultivation mosaics, hazelnut groves, irrigated citrus groves and orchards, greenhouses, built-up areas).

Bio-ecological, phytosociological and conservation aspects of relictual and disjointed populations of Simethis mattiazzi (Vandelli) Sacc. (Xanthorrhoeaceae) in the Channel of Sicily

Abstract Two populations of Simethis mattiazzi (Xanthorrhoeaceae) were recently discovered in the Channel of Sicily – (1) Punta Bassana (Marettimo Island) and (2) Mount S. Giuliano (western Sicily) – at a considerable distance from the nearest stations hitherto known, located in southern Sardinia, the Pontine Islands Archipelago and Tunisia. The taxonomical and distributive aspects of this species are analysed to highlight the relictual and biogeographical significance of the disjointed and fragmentary nuclei distributed in several small islands of the Channel of Sicily, the Italian Peninsula and North Africa. Some morphological, biological, ecological and phytosociological aspects of the two new populations are analysed to assess risk factors. These relictual populations are included in a residual garrigue ascribed to the association Erico–Micromerietum fruticulosae, endemic to western Sicily and characterized by a significant frequency of endemic or rare species. The coenose is tied to the calcareous dolomite rocky ridges located near the coast and exposed to humid currents from the sea; this ecological combination gives to the habitat a character of oceanic environmental conditions, somewhat similar to the Atlantic stations where the main range of the species gravitates. The survey has shown the populations to be formed of a small number of individuals at both stations, which has further highlighted the biological precariousness of these populations, located at the extreme south-eastern limit of the range of the species. The threats of anthropogenic nature, such as reforestation with non-native conifers, but mostly by fires, the frequency of which tends to alter the integrity of the sites, increase this vulnerability. The IUCN “risk status” for the regional territory of Sicily of S. mattiazzi is to be ascribed to the “Critically endangered” category, in accordance with the B1ab (ii) and B2ab (ii) criteria of the IUCN. The same “risk status” is likely to be extended to the other isolated stations of the western Mediterranean.

Distribution, ecology, vegetation and conservation survey on the relictual population of Carex panormitana Guss. (Cyperaceae) in Sicily (Italy)

We report the results of research on the Carex panormitana Guss. (Cyperaceae) population in Sicily, carried out within its locus classicus at the Oreto River (Palermo). The survey led to a morphological, biological and autoecological characterization, to the definition of the current distribution in the site, to an estimate of the number of individuals and to an analysis of its conservation status. The risk status was also assessed and the species was ascribed to the category Critically Endangered (CR), in accordance with the CR B1ab (ii, iii, v) and EN C1 IUCN criteria. Moreover, the phytosociological survey carried out on the meso-hygrophilous vegetation in which the species is dominant allowed description of the association Caricetum pendulo-panormitanae ass. nova, in turn framed into the alliance Magnocaricion elatae (ord. Magnocaricetalia, cl. Phragmito-Magnocaricetea).

Distribution, ecology and conservation survey on Trifolium michelianum Savi (Fabaceae) in Sicily (Italy)

We report the identification of four residual stations for Trifolium michelianum Savi (Fabaceae) in Sicily, whereas the species was documented to be extinct at the Gorgo Cerro station (western Sicily), the only locality previously reported in the literature. In addition to an update on the distribution of the species, a survey on the new Sicilian populations led to their biological, ecological and phytosociological characterization, as well as to an assessment of the risk factors. The species, here relegated to the limit of its distribution area, occurs in particularly sensitive and vulnerable environments, such as the “Mediterranean temporary ponds”, considered “priority” by the Council Directive 92/43/EEC. Moreover, a new Sicilian association (Trifolio micheliani–Glycerietumspicatae ass. nova), framed in the alliance Glycerio-Sparganion (class Phragmito-Magnocaricetea), is described.

Distribution, ecology and conservation survey on the Celtis tournefortii subsp. aetnensis (Celtidaceae: Cannabaceae) populations in Sicily

Results of research on the Celtis tournefortii subsp. aetnensis (Celtidaceae: Cannabaceae) populations in Sicily, based on the monitoring of the various nuclei distributed in the territory, are presented. In particular, two new important unpublished stations located in the southern part of the Sicani Mountains, widespread over an area of approximately 75 hectares, are reported. It is highlighted that the species, besides the lava flows of the western slope of Mount Etna (Catania province), is tied to conoids present in five other disjointed sub-ranges, often with fragmentary and relictual stations: (1) Nebrodi Mountains inland (Cesarò territory, Messina province); (2) Madonie Mountains inland (Gangi territory, Palermo province); (3) northwestern sector, in the Palermo province (Rocca Busambra); (4) southwestern Sicani Mountains (Pizzo Telegrafo, in Contrada S. Biagio and in the Caltabellotta territory, Agrigento province); (5) southeastern Sicani Mountains (S. Stefano di Quisquina at Pizzo Castelluzzo, Agrigento province). In addition to a herbarium exsiccata census, the survey led to a biological and autoecological characterization, to the definition of the current distribution, to an estimate of the number of individuals and to an analysis of its conservation status. The risk status was also assessed and the species was ascribed to the category Endangered (EN), in accordance with the B1ab(iii) and B2ab(iii) IUCN criteria.

Phytosociological analysis of the Genista sp. pl. garrigues of the Cisto-Lavanduletea and Rosmarinetea officinalis classes in the South-Tyrrhenian area (Mediterranean Region)

The study reviews the Genista sp. pl. garrigues ascribable to the classes Cisto-Lavanduletea (acidophilous communities on volcanics and quartzarenites) and Rosmarinetea officinalis (basiphilous communities on calcareous and calcareous-dolomite substrates), in the southern territories of the Italo-Tyrrhenian Province. The floristic-synecological characterization of the identified coenoses led to the description and/or redefinition of various new syntaxa. They are distributed in the two new suballiances Calicotomo villosae–Genistenion tyrrhenae and Genisto aristatae–Calicotomenion infestae of the class Cisto-Lavanduletea (Lavanduletalia stoechadis and Calicotomo villosae–Genistion tyrrhenae), and in the alliance Cisto eriocephali–Ericion multiflorae of the class Rosmarinetea officinalis (Rosmarinetalia officinalis), with two new described associations.