149 research outputs found

    Acer-Fraxinus dominated woods of the Italian Peninsula: a floristic and phytogeographical analysis.

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    Forest communities dominated by noble broad-leaved trees (maple, lime and ash) in Europe are of elevated scientific and con­servation interest for the European Union. In this paper, we first present a synthesis of the maple and ash forests in peninsular Italy. By classifying these forests, we distinguish seven main groups for the territory, which only broadly match the syntaxa proposed in the literature. The variability of the Apennine data is then analysed floristically and phytogeographically (using chorological components) in a central-southern European context, using numerical classification, INSPAN, and direct ordination of several synoptic tables. These analyses allow us to identify six different groups of European Acer-Fraxinus communities. Canonical Vari­ates Analysis (CVA) of the geographical components confirms the existence of distinct phytogeographical groups. In particular, we highlight the clear distinction between central European (including the Alps) and southern European coenoses. Among the latter there was a clear floristic and chorological distinction between Balkan and Apennine groups. These results reflect the biogeographical subdivisions of Europe, but do not support the syntaxonomical schemes proposed by other authors, which are based only on floristic-ecological information or (recently) use a smaller data set of Italian relevés. This study also shows that syntaxonomical schemes above the association level should pay more attention to phytogeographical aspects rather than focus on floristic-ecological information alone, in order to propose models that are of value on a geographical scale

    Travišča razreda Festuco-Brometea na podlagi iz peščenjaka in laporasto-glinastega peščenjaka v Toskani (severna osrednja Italija)

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    The grasslands dominated by Bromus erectus and/or Brachypodium rupestre cover large areas on sandstone and marl-clay-sandstone substrata (limestone is excluded), of the Apennines and pre-Apennines between Pistoia and Arezzo provinces (Tuscany, Central Italy). Our investigation was focused on to 71 unpublished relevés and 45 literature relevés from Tuscany and surrounding areas, reporting the original relevés of Astragalo monspessulani-Brometum erecti, Centaureo bracteatae-Brometum erecti and Ononido masquillerii-Brometum erecti. The relevés were submitted to exploratory multivariate analysis, allowing to detect nine distinct groups. Their consistence was verified by mean of NMDS against Ellenberg/Pignatti indicator values, and CCA constrained against chorotypes and growth forms. Diagnostic species of the definitive groups resulting from the analysis were chosen according to species fidelity, based on the φ coefficient of association. The analysis splits the data set in two main subclusters; the first one (A) includes few relevés of low altitude, thermophilous conenoses, interpreted as a transition between the submediterranean aspects of Festuco-Brometea class and other Mediterranean herbaceous and shrubby classes; the second subcluster (B) includes most of the data set and can be clearly subdivided in pioneering, mesoxerophilous communities (B1 and B2a groups) and mesophilous communities (B2b group). The relevés of clusters B1 and B2a are referred to Coronillo minimae-Astragaletum monspessulanii association and to three other groups: Plantago argentea-Carex caryophyllea communities, Tragopogon samaritani-Bromus erectus communities, Festuco trachyphyllae-Brometum erecti ass. nova. The mesophilous group (B2b) includes the original Centaureo bracteatae-Brometum erecti and Ononido masquillerii-Brometum erecti relevés, together with a slightly differentiated community; due to the non-relevant differences between these grassland types from floristic, ecological and chorological perspectives, we propose herewith to treat them as three subassociations of Centaureo bracteatae-Brometum erecti (typicum, ononidetosum masquillerii and linetosum cathartici). Post-cultural grasslands in human-disturbed areas were also detected. All these communities can be attributed to Polygalo mediterraneae-Bromenion erecti suballiance (Bromion alliance), even if a clear subdivision between the mesoxerophilous pioneer aspects and the more mesophilous and evolved ones can be noted.Travišča v katerih prevladujeta vrsti Bromus erectus in/ali Brachypodium rupestre pokrivajo velike površine na podlagi iz peščenjaka in laporasto-glinastega peščenjaka (apnenec je izključen) na Apeninih in območju pred njimi med provincama Pistoia in Arezzo (Toskana, srednja Italija). Naša raziskava je bila osredotočena na 71 neobjavljenih in 45 objavljenih vegetacijskih popisov iz Toskane in sosednjih območij. Originalni popisi opisujejo asociacije Astragalo monspessulani-Brometum erecti, Centaureo bracteatae-Brometum erecti in Ononido masquillerii-Brometum erecti. Popise smo obdelali z multivariatno analizo s katero smo zaznali 9 skupin. Konsistenstnost skupin smo preverili s povprečjem NMDS proti Ellenberg/Pignatti indikatorskim vrednostim in CCA proti horotipom in rastnim oblikam. Diagnostične vrste posameznih skupin smo določili z navezanostjo vrst, ki temelji na φ koeficientu asociacije. Z analizo smo podatkovni niz razdelili na dva klastra; prvi (A) vključuje nekaj popisov termofilne cenoze z nižje nadmorske višine, ki jih opišemo kot prehod med submediteranskim aspektom razreda Festuco-Brometea in drugih mediteranskih zeliščnih in grmiščnih razredov; drugi klaster (B) pa vključuje večino podatkovnega niza in ga lahko členimo na pionirske, mezokserofilne (skupini B1 in B2a) in mezofilne združbe (skupina B2b). Popise klastrov B1 in B2a uvrščamo v asociacijo Coronillo minimae-Astragaletum monspessulanii in tri druge skupine: združba Plantago argentea-Carex caryophyllea, združba Tragopogon samaritani-Bromus erectus in Festuco trachyphyllae-Brometum erecti ass. nova. Mezofilna skupina (B2b) vključuje popise asociacij Centaureo bracteatae- Brometum erecti in Ononido masquillerii-Brometum erecti, skupaj z delno spremenjeno združbo. Zaradi majhnih razlik v florističnem, ekološkem in horološkem pogledu med temi traviščnimi tipi predlagamo, da jih obravnavamo kot tri subasociacije Centaureo bracteatae-Brometum erecti (typicum, ononidetosum masquillerii in linetosum cathartici). Opisali smo tudi nekaj negospodarjenih travišč na motenih rastiščih. Vse združbe lahko uvrstimo v podzvezo Polygalo mediterraneae- Bromenion erecti (podzveza Bromion), čeprav je opazna delitev med mezokserofilnim pionirskim in mezofilnim in bolj razvitim aspektom

    Analysis of genetic structure of Ranunculus baudotii in a Mediterranean wetland. Implications for selection of seeds and seedlings for conservation

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    Seed collection and storage of wild species in ex-situ seed banks should be continued as an integrated tool for the conservation of plants in their habitats. Although seed-bank facilities are widely used today, their seed samples often suffer low genetic diversity. Consequently, reintroduced seeds and plant material may not have the resilience to cope with future environmental stress so leading to complete wastage of seeds. Molecular techniques allow the benefit of quantification of the genetic diversity of a seed collection in comparison with that of the natural population. In this study we focus on ex-situ seed bank samples and living collections of Ranunculus peltatus subsp. baudotii. We compare their genetic diversity and structure with that of the natural population before and after undertaking a restoration project on a natural pond in the Tuscan Archipelago National Park. ISSR analyses, carried out on a total of five sampling groups, shows a relatively high level of genetic diversity for the ex-situ cultivated groups. The analysis of molecular variance, in agreement with clustering obtained in the neighbour-joining dendrogram and with the pattern from cluster analysis, suggests dividing the samples analysed into two groups: one formed by individuals sampled before the pond restoration and the other formed by the subsequent pond population. The results highlight the importance of planning mixed propagation lines which can be obtained through the use of a range of germination conditions to exploit a novel source of genetic variability which may otherwise remain hidden within the seed collection

    Secondo contributo alla conoscenza della flora esotica dell'Arcipelago Toscano, Italia

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    Si presenta qui un secondo contributo per la realizzazione di una Checklist della flora esotica dell'Arcipelago Toscano. Per ogni taxon sono riportati lo status di naturalizzazione, sia per ciascuna isola che per l'intero Arcipelago, e i dati relativi alla distribuzione locale. Delle 31 specie elencate, 18 risultano nuove per il territorio dell'Arcipelago Toscano, tra le quali 4 nuove per l'intera Toscana; le restanti sono nuove per una o più isole

    The Nardus-rich communities in the northern Apennines (N-Italy): a phytosociological, ecological and phytogeographical study

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    Secondary grasslands dominated by Nardus stricta are an anthropogenic vegetation type that occurs widely through the Europe from lowlands to mountains. These communities have been recently recognized by the European Community as a habitat of priority interest. The aim of the study is to perform a detailed and complete phytosociological scrutiny of this vegetation in the northern Apennines. Further aims are to detect the factors controlling the floristic variation within these communities and to analyse the variations of Nardus grasslands along a latitudinal gradient from the northern Alps to the southern Apennines. We processed a set of 134 phytosociological relevés from the northern Apennines through a cluster analysis based on Kendall’s tau dissimilarity measure. Results showed the occurrence of two different associations of Nardus grasslands (Carlino caulescentis-Nardetum strictae and Violo ferrarinii-Nardetum strictae). Relations between their floristic composition and environmental variables were detected through Redundancy Analysis. The matrix of habitat factors included topographic variables and variables derived from Ellenberg’s indicator values. Elevation was the factor explaining most of the floristic variation. From the comparison of 44 synoptic tables from the Alps, Carpathians and Apennines, processed through a NMDS ordination, we detected two main phytogeographic and ecological thresholds along the latitudinal gradient

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

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    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

    Limonium gorgonae Pign.

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