1,721,208 research outputs found
Distribution of Santolina etrusca (Lacaita) Marchi et D'Amato [Il pattern di distribuzione di Santolina etrusca (Lacaita) Marchi et d'Amato]
No full textThe results of bibliographic, herbarium and field studies on the distribution of Santolina etrusca are reported. The species has a disjoint, bipolar distribution with a northern group of populations along the Lima and Arno rivers (Pistoia, Lucca, Florence and Arezzo provinces), known from late nineteenth century herbarium specimens but not confirmed, and a southern group including Mt. Amiata and surrounding areas (centre of dispersal), the Maremma area, the Orcia and Paglia valleis, the Tuscia and a small area near Orvieto (Siena, Grosseto, Viterbo and Terni provinces). The distribution of the species is linked to water courses which are its preferred habitat. © 2018 Società Botanica Italiana onlus
Information on the distribution and phytosociological study of communities with Santolina insularis (Gennari ex Fiori) Arrigoni in southern Sardinia (Italy) [Analisi distributiva e studio fitosociologico delle comunità a Santolina insularis (Gennari ex Fiori) Arrigoni della Sardegna meridionale]
No full textInformation on the distribution and phytosociological study of communities with Santolina insularis (Gennari ex Fiori) Arrigoni in southern Sardinia (Italy). Santolina insularis is a polyploid endemic distributed mainly in the south and central-eastern parts of Sardinia (Italy). It is found from sea level to the summit of Mt. Gennargentu (1834 m a.s.l.). This paper provides up-to-date information on the distribution of the species and the results of phytosociological study of the communities found in southern Sardinia. Two new associations called Euphorbio cupanii-Santolinetum insularis and Thymelaeo hirsutae-Santolinetum insularis are proposed on the basis of 37 original relevés and two from the literature. The former is linked to glareicolous environments of the Iglesias area and has two subassociations which vicariate in relation to substrate rocks and their physicochemistry, as well as bioclimatic and syndynamic conditions. The second is characteristic of non-stabilised alluvial beds of the Sarrabus-Gerrei and was hitherto regarded as a variant of the association Polygono scoparii-Helichrysetum microphylli. The two associations are related syntaxonomically through the alliance Teucrion mari, which includes chamaephytic vegetation with distribution in Sardinia and Corsica, indifferent to substrate chemistry and capable of establishing on degraded soils in the initial stages of pedogenesis. © 2013 Fitosociologia. All rights reserved
The distribution of Osmunda regalis L. in Tuscany [Contributo alla conoscenza della distribuzione di Osmunda regalis L. in Toscana]
No full textThe results of bibliographic, herbarium and field studies relative to the distribution of Osmunda regalis are reported. The species is distributed in the west of the region in some principal groups (dispersal centres): at the base of the Alpi Apuane, in lower Arno Valley (Padule di Fucecchio-Monte Pisano- San Rossore), in Merse Valley, on Monte Leoni, in the Tuscan Archipelago (Elba and Giglio islands) and in the Argentario area. The distribution of the species is linked to springs swamps, water ways and marshes in a range between 0 and 600 m of altitude. New sites in southern Tuscany have been located through field research, and some old sites have been examined to verify the distribution of the species in recent years. The risk of its extinction in Tuscany is mainly due to degradation and reduction of habitat. Some information about the rarity of the species at a regional level is also provided. © 2018 Società Botanica Italiana onlus
Distribution of endemic and alien plants along Mediterranean rivers: a useful tool to identify areas in need of protection?
No full textThe main aim was to obtain information about the more critical sectors of Mediterranean-type rivers, especially in the islands where the percentage of endemic species is high, even in riparian habitats. Our hypothesis was that endemic and alien species, considered important in defining conservation priorities along rivers, have different patterns of distribution and their coexistence indicates human impacts on fluvial systems, which can cause natural habitat loss. Generalized Additive Models were used to model the distribution patterns of endemic and alien species along the longitudinal gradient. They showed that endemic species were linked to the most natural areas in the middle and upper sections of the rivers, whereas the distribution of aliens in middle and lower sections can be regarded as a consequence of human impact. This finding underlined the presence in the middle sections of the rivers of areas with important floristic features that are also affected by alien species. What currently seems a situation of equilibrium turns out to call for careful control, first and foremost, by maintaining riparian vegetation. Our results highlighted the utility of our method for rapidly obtaining information about the criticalities of rivers in Mediterranean biodiversity hotspots. © 2013 Académie des sciences
An integrated approach to support a river ecological network: A case study from the Mediterranean
Full text linkRiverine ecosystems are among the most impacted ecosystems worldwide since they are exposed to multiple stressors. Land Use/Land Cover (LULC) changes is the main human imprint on those ecosystems whose spatiotemporal habitat destructions pose a threat to biodiversity, ecosystem integrity and ecological processes. The most important statutory instruments for riverine ecosystem protection, conservation and restoration in the European Union are the Water Framework Directive (WFD) and the Habitats and Birds Directive (HBDs). In this study, we develop a methodological framework to spatially link the ecological integrity of river sub-basins with the protected areas therein, taking into account the influence of land use as expressed in the WFD. We combined a multi-criteria evaluation approach using six of the most frequently applied criteria for conservation evaluation to assess river basin integrity (RBI) index at the sub-basin level, and used as a proxy for functional connectivity categories. In addition, we used the distance of every sub-basin from the surrounding Natura 2000 sites as a measure of structural connectivity. Using ecological network design principles (i.e. Core areas; Corridors; Stepping Stones; Buffer areas; and Restoration areas), we incorporated the two aspects of connectivity into a framework, which links river management at the basin level with the site level assessment as dictated by the HBDs. We implemented this framework in a Mediterranean river basin located in Southern Tuscany, which is part of the Natura 2000 network. Six of the sub-basins (20%) have high functional connectivity, 14 sub-basins (47%) medium and 10 sub-basins (33%) low functional connectivity. Structural connectivity of the study area followed the same tendency as that of functional connectivity, with the majority of the sub-basins having medium connectivity (57%; 17 sub-basins), and 23% (7 sub-basins) and 20% (6 sub-basins) high and low structural connectivity respectively. As a result, six of the sub-basins were characterised as corridor areas while the majority of the sub-basins were identified as buffer areas (57%). Two sub-basins were characterised restoration areas and one as stepping stone (SS). Our approach is one of many plausible ecological networks, which although analytically simple, can be enriched with data on species and stakeholders' involvement
Analisi fitosociologica dei fiumi della Toscana meridionale: il tratto medio-basso del Merse (Italia centrale)
No full textAfter a brief introduction on the geological, hydrological and
climatic characteristics, the authors describe the results of a phytosociological study
concerning riparian and aquatic vegetation of the lower-middle Merse river (southern
Tuscany, central Italy). Purpose of the contribution is to further knowledge on the
syntaxonomy, ecology and dynamics of river vegetational communities in southern
Tuscany. The paper outlines a rather complex syntaxonomy scheme pointing out the
vegetation abundance of the section of the river studied. In fact, coenosis belonging
to 12 different phytosociological classes were identified: Querco-Fagetea, Salicetea
purpureae, Rhamno-Prunetea, Rosmarinetea officinalis, Molinio-Arrhenatheretea,
Artemisietea vulgaris, Isoeto-Nanojuncetea, Bidentetea tripartitae, Agrostietea
stoloniferae, Phragmito-Magnocaricetea, Potamogetonetea pectinati, Charetea
fragilis. High environmental quality was evidenced by floristic and synecological
analysis of the community. Due to the low presence of human activity, hydrophytic
community indicating oligotrophic aquatic environment, high phytocoenotic
diversity, floristically, structurally and ecologically well characterized tree/shrub
population were found
Conservation status of Mediterranean coastal dune habitats: anthropogenic disturbance may hamper habitat assignment
No full textCoastal dunes are rich in habitats with a high heterogeneity in species composition. Though widely recognized as very fragile and dynamic ecosystems, they are systematically overexploited. In addition, mismanagement contributes making these habitats highly endangered, especially in the Mediterranean area. In this study, an impoverished dune system was used to investigate whether the lack of indicator species, including characteristic, main diagnostic, alien and non-typical, could mislead habitat assignment. Coastal dune plant communities used in this study are embedded into a high anthropogenic pressure territory, primarily due to the vicinity to a city and by hosting bathing facilities. A cluster analysis based on 49 vegetation plots (releves) was performed in order to assign dune vegetation units to EU habitats (92/43/EEC Habitat Directive) and corresponding phytosociological units. Eight habitat types were classified and two of them were of priority importance. Twelve plant communities belonging to eight different phytosociological classes were recognized. The plant cover value of characteristic, main diagnostic, alien and non-typical plant species, was used to assess the conservation status of each habitat type. Despite the presence of well-preserved plant community, almost all habitats were in unfavourable conservation status. Furthermore, a floristic impoverishment and a zonation interruption on the stabilized dunes were found. This study underlines the difficulty to identify typical coastal dune plant communities and associated habitats when anthropogenic disturbance dramatically changes the environmental conditions. Specific conservation and management actions for the sustainable maintenance of these endangered habitats are suggested
Distribution of Nymphaea alba L. (Nymphaeaceae) in Tuscany [Distribuzione di Nymphaea alba L. (Nymphaeaceae) in Toscana]
No full textThe authors report the distribution of Nymphaea alba L. in Tuscany by the analysis of herbarium specimens, bibliographic references and records on field. The study shows two different situations: the species is distributed almost exclusively along the wetland's net on the northwestern floodplains in the district of Florence, Pistoia, Lucca, Pisa and Massa. Except for few and isolated sites, in the districts of Arezzo, Siena and Grosseto, the species seems not to occur in the rest of Tuscan wetlands. © 2018 Società Botanica Italiana onlus
Notes about Ononis viscosa L. and O. breviflora DC. in Italy [Alcune note su Ononis viscosa L. e O. breviflora DC. in Italia]
No full textOnonis viscosa L. and O. breviflora DC. are two very closely related entities from a morfological and ecological point of view so that many authors consider them subspecies or even varieties. This contribution investigates their real presence in Italy by analyzing herbarium samples, bibliographic data and direct observation in the field. The length of the corolla compared to the calyx and of the raceme axis compared to the axilla leaf under the arista are two constant characters that differentiate them and all the italian samples examined, including those referred to as O. viscosa in the past, could be included in the variety of O. breviflora if the binomial be valid. The results of this research allows us to exclude O. viscosa from the Tuscan and Italian floras even through the systematic problem af the two taxa remains open and worthy of further study. © 2018 Società Botanica Italiana onlus
Grasslands of the order Brometalia erecti Br.-Bl. 1936 on Antiapennine calcareous massifs in central-southern Tuscany (central Italy)
No full textFloristic characteristics, syntaxonomy and synecology of grasslands of the order Brometalia erecti on calcareous massifs of central-southern Tuscany are reported. Multivariate analysis was used to compare 64 phytosociological relevés made in the years 1997, 2000 and 2001. These pastures occur in areas of the temperate oceanic region, with upper hill to montane thermotype and lower humid to lower hyperhumid ombrotype, in serial contact with woods of Ostrya carpinifolia Scop. and with beech woods on summits. The plant communities surveyed were classified in the following associations: i) Cerastio etrusci-Brometum erecti ass. nova (Phleo-Bromion Biondi and Blasi ex Biondi and al. 1995), identified for xeric grasslands on moderate to steep slopes with basic lithosols in the hill and lower montane belts; it has two variants related to soil chemical and physical characters; comparison with similar vegetation of other Apennine areas confirms the western connotation and autonomous nature of these communities; ii) Trifolio incarnati-Brometum erecti Oberdorfer and Hofmann 1967 (Bromion W. Koch 1926), known from the Ligurian Apennine downwards; in the area studied it shows a new «Antiapenninic» subassociation named phleetosum ambigui that includes: a mesophilous variant with Arrhenatherum elatius, related to flat or north-exposed stations in the mountain belt linked to mature soils with high moisture all year, rich in transgressive species of the class Molinio-Arrhenatheretea Tüxen 1937; a subnitrophilous variant with Carlina corymbosa, related to grazing and exclusive to soils with high clay component; a transition variant towards xerophilous grasslands. The study confirms the presence of the alliance Phleo-Bromion in Tuscany as an isolated appendage with northern outposts of xerocalcicolous communities widespread in the central-southern Apennine; a similarity with vegetation of northern Tyrrhenian sectors was also observed
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