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1.
This study is aimed at (1) producing a complete and updated inventory of the endemic vascular flora of Peloritani Mountains, (2) defining the geographical limits of Peloritani, regarded here as a biogeographical district and (3) highlighting possible paleogeographic connections with other Mediterranean lands. The heterogeneity analysis of the endemic flora was performed by means of contingency tables, through the χ2 test. The endemic flora of this area consists of 129 specific and infraspecific taxa, of which 15 are restricted to the Peloritani Mountains. The analysis of habitats revealed that endemic taxa are most abundant on cliffs, rangelands, woods and garrigues. A large number of surveyed taxa are endemic to central-southern Italy and Sicily, while the number of endemic taxa in common with Calabria, Etna and Aeolian Islands turned out to be rather low, in spite of the geographical proximity. The endemic flora of Peloritani allows to emphasize palaeogeographical relationships not only with the neighbouring Mediterranean territories, but also with currently remote ones, such as southern Spain, Sardinia and Corsica. The phytogeographical framework substantiates the hypothesis that the Peloritani floristic district coincides with the limit given to Peloritani Mountains by structural geologists. 相似文献
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Donatella Serio 《Plant biosystems》2013,147(6):941-973
Abstract A study on Cystoseira spinosa community and Cystoseira zosteroides community from Catania (Eastern coast of Sicily) is presented. It is based on monthly samples carried out throughout a year. That permitted to better characterize the communities as regards their periodism and floristic composition. From the comparative examination of samples made, resulted that the communities differ each other mainly in the Cystoseira species since their floristic composition are on the whole quite similar. 相似文献
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Abstract A new association, Chrysopogono grylli-Nerietum oleandri, situated in the south of Croatia, is proposed. According to its floristic structure, physiognomy and ecology, it belongs to the Rubo ulmifolii-Nerion oleandri alliance (Tamaricetalia, Nerio-Tamaricetea). It is the only association with Nerium oleander in Croatia. This community has developed along a temporary watercourse as a vegetation exclave (extrazonal stand) within the climazonal evergreen forest vegetation of the Oleo-Ceratonion alliance. The association has a thermophilous character and a large number of companions from the Quercetalia ilicis and Scorzonero-Chrysopogonetalia communities. This report compares the floristic composition of this association with others of the Rubo ulmifolii-Nerion oleandri alliance from other Mediterranean areas. The Croatian association is most similar to the Spartio-Nerietum oleandri association from the Ionian side of Calabria (south Italy). The syntaxonomic status of the Montenegrin association Andropogono distachyi-Nerietum oleandri was determined, and the status of the stands with Nerium oleander is discussed. 相似文献
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A consistent vegetation classification is an essential tool for conservation and monitoring purposes, also for semi-natural habitats such as pastures and hay meadows that are linked to traditional land use and generally considered crucial to maintain biodiversity within agricultural systems. Indeed, these habitats can be strongly affected by land abandonment or agriculture intensification. Despite their importance in the framework of the EU Habitats Directive (43/92/EEC), information on distribution, species composition, and conservation status is still lacking for many regions. To fill these gaps, we investigated from a phytosociological point of view the sheep pastures of the North-Western Sardinian trachy-basaltic sector. Three main communities were described as new: (i) perennial montane (meso-supratemperate) cattle and sheep pastures (Loto alpini-Festucetum morisianae); (ii) mixed (annual and perennial) Mediterranean (lower Thermomediterranean to lower supratemperate) sheep pastures (Ornithogalo corsici-Poetum bulbosae); and (iii) annual ploughed subnitrophilous Mediterranean and Temperate pastures (Cynosuro polybracteati-Vulpietum ligusticae). As the first two host numerous endemic taxa and show a peculiar floristic composition, we assign them a higher conservation value, testified also by their classification in two new syntaxa: Danthonio decumbentis-Caricenion insularis (Molinio-Arrhenatheretea) and Ornithogalo corsici-Trifolienion subterranei (Poetea bulbosae), respectively. 相似文献
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Estuarine intertidal soft-bottom macrobenthic infauna of the Tagus estuary was characterised using different mesh size sieves
and sediment sampling depth. The study sampled 105 sites using a hand held 0.01 m2 corer. The top layer (0–5 cm) was sieved through nested 1.0 and 0.5 mm meshes whereas the bottom layer (5–20 cm) was through
a 1 mm mesh. The total survey took 26 taxa of more than 5800 individuals and a total wet weight biomass of over 650 g. The top layer, using both sieves, gathered 23
taxa (92% of the total), more than 5600 specimens (96%) but less than 8 g of biomass (1%) whereas the 1.0 mm sieve retained 21
taxa (91%), more than 1700 specimens (31%) and almost 7 g of biomass (1%). Abundance was dominated by small annelids, of which
Streblospio shrubsolii was 68%, whereas biomass was dominated by molluscs, with the bivalve Scrobicularia plana representing 98%. Multivariate analyses showed an abundance pattern where the top layer data was very similar to that obtained
with both layers. The bottom layer data were needed to accurately represent the total biomass pattern. The macrofaunal spatial
pattern identified with the 0.5 mm sieve data differed from that identified by the 1.0 mm and was essential to discriminate
a faunal assemblage located along the upper part of the shore. It was concluded that in order to characterize the macrofauna
community structure, based on the presence/absence of taxa, the top layer and a 1.0 mm sieve would be sufficient. An abundance-based characterization requires the top layer and a 0.5
mm sieve whereas a biomass-based characterization requires data for both layers but it is sufficient to use the 1.0 mm sieve.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
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A new species of Cremosperma (Gesneriaceae, tribe Beslerieae) is described from the Chocó floristic region of the western Andean slopes of northern Ecuador
and southern Colombia. The dorsiventral shoots and strongly anisophyllous leaves differentiate Cremosperma anisophyllum from all other congeners. 相似文献
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Abstract The terrestrial orchid, Orchis pauciflora Ten., growing in poor grassland and garrigue of Central Mediterranean region, is local and rare and has been included in the red lists of several Italian regions. We investigated the diversity of fungal associates in O. pauciflora adult plants collected in two protected areas of Tuscany (Central Italy). Genomic DNA was extracted from mycorrhizal roots of 12 orchid plants and the fungal ITS were amplified and sequenced. Several fungal associates, belonging to different taxa of basidiomycetes (Tulasnellaceae) and ascomycetes such as Leptodontidium, Exophiala and Phialophora species, were recovered. The trophic role of these fungi and their impact on O. pauciflora growth and conservation are discussed. 相似文献
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Paula Chainho M. F. Lane M. L. Chaves J. L. Costa M. J. Costa D. M. Dauer 《Hydrobiologia》2007,587(1):63-78
Taxonomic sufficiency has been used mainly to assess benthic condition, based on the assumption that taxa can be identified to a taxonomic level higher than the species level without losing the ability to detect changes related
to pollution stress. Identifying taxa to a higher level reduces the expertise and time needed to identify organisms and consequently allows increased spatial and
temporal replication. The usefulness of taxonomic sufficiency for typology (identification of water body types) was examined
using the benthic communities of the Mondego River estuary (Portugal). Benthic samples were collected seasonally along the
Northern branch of the Mondego River estuary from July 2000 to June 2001 and several environmental parameters were measured
simultaneously. Cluster analysis of species data indicated three major ecological groups, mainly related to a saline gradient
along the estuary. The same groups were found when taxa were aggregated to higher taxonomic levels (genus, family, order, class), except for the phylum level. The overall spatial
pattern was driven by: (1) the dominance of bivalves and the occurrence of rare marine species in the Lower Estuary; (2) the
dominance of polychaetes in the Middle Estuary; (3) and the dominance of arthropods in the Upper Estuary. The ability of different
taxocenes to discriminate the three ecological groups was also examined. Mollusca and Bivalvia were the only taxocenes producing
the same groupings, although other taxocenes (Annelida, Polychaeta, Spionidae, Arthropoda) showed a significant ability to
discriminate between all three groups. Compared to using all taxa identified to the lowest possible taxonomic level, our results indicate that for typology (1) several higher taxonomic levels
were sufficient (2) while few taxocenes alone were sufficient.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
10.
《Plant Ecology & Diversity》2013,6(3-4):447-455
Background: High-altitude ecosystems in the Alps have experienced severe environmental changes over the past decades, such as strong warming and increasing numbers of visitors and grazers. Few studies have followed the effects of such changes on the alpine flora over a period longer than a few decades. The summit of Piz Linard (3410 m, south-eastern Switzerland) is the oldest site in the Alps whose flora has been recorded, on average every 20 years since the Little Ice Age (1835). Aims: We re-surveyed the summit flora of Piz Linard to trace its floristic changes and identify their patterns and possible drivers. Methods: We mapped each species' highest location, distribution and abundance in the uppermost 30 m of the Piz Linard summit in 2011, and compared species composition and species’ altitudinal distribution over time. Results: Species richness increased at an accelerated rate since 1992 and rose from 12 to 16 species since the previous record in 2003. Most already present species increased in abundance and colonised new areas of the summit, while new arrivals mainly established at sites with already high species richness. Species appeared after 1992 differed from species already present previously by having had lower maximum altitudes elsewhere in south-eastern Switzerland. Conclusions: Temporal and spatial patterns of colonisations and former altitudinal ranges of species all point to climate warming as the principal driver of floristic change on Piz Linard. 相似文献
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Emanuele Bocchieri 《Plant biosystems》2013,147(5):615-621
Abstract The author reports the results of some floristic research carried out on the islet of Pan di Zucchero (W-SW Sardinia). The presence of endemism and of a low and creeping Artemisia arborescens coverage have been pointed out, as well as a natural unviolated state unique among the Sardinian microinsular habitats, due to the inacessibility of the area. 相似文献
13.
Fernando Tammaro 《Plant biosystems》2013,147(2):49-93
Abstract Flora of Popoli's gorges (Central Italy). — The results of floristic research developed from 1967 to 1969 at the Popoli's gorges (province of Pescara, in Abruzzo, Central Italy) are reported. Short accounts on the geographic position, on the geology and climate of the gorges are given, together with the floristic index of 696 entities, 4 of which are new for Abruzzo. For each species the biological and the phytogeographical categories are indicated; and for the whole of the flora the biological spectrum. This shows that this flora is a submediterranean one, with altitude influences. Critical remarks are developed about the taxonomy and distribution in the region of Abruzzo of several species wich looked particularly significant to the author. 相似文献
14.
Dott. Onorato Verona 《Plant biosystems》2013,147(3):534-537
Abstract Helianthemetea guttati communities are pioneer spring and early summer ephemeral grasslands, dominated by non-nitrophilous therophytes. In Continental Portugal, these communities have not yet been fully investigated, and thus the objectives of the present study are: (1) to identify community types in therophytic grasslands; (2) to recognize those communities that configure the European priority habitat 6220* (pseudo-steppe with grasses and annuals); (3) to establish environmental gradients underlying their spatial variation; (4) to assess how floristic composition is affected by land use factors. Vegetation sampling using phytosociological methodology was carried out on 80 grasslands. Modified Twinspan classification and canonical correspondence analysis (CCA) was applied for the classification and ordination of relevés whereas partial CCA (pCCA) and variation partitioning were used to assess the relative influence of individual land use factors. Some 270 species were identified across 11 community types whose floristic patterns were mainly explained by environmental gradients related to altitude and soil type while land use variables could only explain a small part of the floristic variation. Based on biogeography and the determination of diagnostic species, four phytosociological new associations and a new subassociation are proposed: Holco-Brachypodietum distachyi, Holco-Micropyretum tenellae, Micropyro-Anthoxanthetum aristati and Leontodonto-Vulpietum bromoidis vulpietosum membranaceae. 相似文献
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Daniela S. Carneiro-Torres Inês Cordeiro Ana Maria Giulietti Paul E. Berry Ricarda Riina 《Brittonia》2011,63(1):122-132
While conducting a floristic inventory of Croton from the Brazilian Caatinga, three new species were discovered. Croton arenosus, Croton glandulosobracteatus, and Croton harleyi are described and illustrated here. Based on morphological characters, Croton glandulosobracteatus is proposed to belong to section Barhamia, and C. arenosus and C. harleyi to section Geiseleria. 相似文献
16.
Duilio Iamonico 《Plant biosystems》2013,147(4):923-930
Arenaria bertolonii Fiori & Paol. is an orophyte and endemic European species of Italy and France. The name Stellaria saxifraga Bertol. (basionym of A. bertolonii) is typified on a herbarium specimen kept in BOLO. Infraspecific variability of the species is discussed and a comparison with related taxa included in the Subg. Arenaria was made on the basis of morphological analyses and chorological and cytological data. At the sectional level, the results show that A. bertolonii is clearly separate from the morphological and chorological points of view, thus supporting the proposal for a new monotypic section (Sect. Italiae Iamonico) of central Mediterranean species. The analysis of infraspecific variability instead highlighted overlapping morphological characteristics; the distribution areas of the infraspecific taxa are sympatric and any cytological difference is lacking, thus pointing to a synonymization of the names. Notes on the ecology and distribution of A. bertolonii are also provided. 相似文献
17.
Uberto Tosco 《Plant biosystems》2013,147(3-4):398-430
Abstract The composition of the flora growing on the ground where Turiner Polytechnic School was once located and then destroyed by an air bombardment during the Second World War was investigated. The area of this ground of 15.000 m2., is in the central zone of the town and is limited by Cavour, San Francesco da Paola, Giolitti and Dei Mille Streets. The actual flora consists of about 160 taxa, making an ensemble of ruins and dry grounds plants, but with an evident contribution also of meadow plants, which, under favorable conditions, group themselves the same as neglected meadows in the suburbs. The analysis of this vegetable grouping suggests some assumptions on the dynamics of the vegetation and on the transformations occurred since the day of the pioneering. Some rare or in town ruins Turiner flora unknown plants are described, which could be saved there thanks to the fact that the continued disturbing and treading action of man was avoided; in fact the admission to the above-mentioned area had been precluded. A list of the observed or collected taxa follows, with the addition of some phyto-phenological findings. A summary of the occurring of the observed patterns, according to their belonging to the vegetation bands and to their diffusion area, concludes the investigations. 相似文献
18.
Yingying Liu 《Plant Ecology & Diversity》2016,9(1):55-62
Background: Tropical rainforests represent the most species-rich and at the same time the most fragmented terrestrial biome on Earth. Fragmentation of tropical rainforests is having wide-ranging consequences for the maintenance of local species diversity and community assembly patterns.Aims: To examine floristic changes and changes in community phylogenetic structure in the forest fragment over the past five decades.Methods: A new taxonomic diversity algorithm (within-family diversity) was developed to assess floristic changes in the forest fragment. Community phylogenetic structure was then compared before and after fragmentation.Results: Taxonomic diversity changed greatly among families, with changes occurring randomly across the phylogeny. The forest fragment had higher phylogenetic diversity, higher mean pair-wise phylogenetic distance, but lower mean nearest-neighbour distance. The community phylogenetic structure has changed significantly from clustering to dispersion.Conclusions: High species turnover occurred in the forest fragment. While shade-tolerant species have been lost, and ruderal and alien species have been added, overall phylogenetic diversity has increased with species being more phylogenetically distant. Competitive exclusion, which was related to the relatively drier conditions in the forest after fragmentation, led the plant community phylogenetic structure to be more dispersed. 相似文献
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Alessandro Menghini 《Plant biosystems》2013,147(6):319-349
Abstract Flora of the clays and the tuffs of Civita di Bagnoregio (Upper Latium). — This work is the result of floristic research developed from 1968 to 1970 on tuffs and mainly on the clays of Civita di Bagnorcgio. After having summarily described the geo-ecological conditions, the author lists in all 489 entities. The biological spectrum of clays shows a high presence of Therophyta and a low percentage of Phanerophyta; on the contrary on the tuffs are present more Phanerophyta and less Therophyta; on the whole the flora is marked from the Emicryptophyta. Phytogeographical analysis indicates a prevalence of mediterranean elements. The author delineates moreover the most important floristic aspects, refering the frequentest entities and point out the intense anthropization wich has prevented the preservation of the woody formations, today completely away from clayey area. 相似文献
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Abstract The floristic composition and spatial structure of a West African riverine forest in north-western Benin were studied in order to identify vegetation zones and their arrangement and composition. Data were collected on five continuous belt transects and were analysed using multivariate methods. A total of 133 tree taxa from 34 plant families were identified, with Rubiaceae and Leguminosae-Papilionoideae as the most frequent families. Fifteen homogeneous transect sections were documented. Near-river sections were dominated by water-demanding species (Syzygium guineense, Garcinia ovalifolia, Berlinia grandiflora, Breonardia salicina) (=gallery forest), whereas uphill sections were characterised by savanna species (Terminalia laxiflora, Hymenocardia acida, Detarium microcarpum, Burkea africana) (= savanna). The shift from gallery forest to savanna was reflected by a floristic turnover and the different physiognomy of the vegetation, although diversity values for gallery forest and savanna were very similar. In the Principal Co-ordinates Analysis (PCoA), gallery forest and savanna sections did not overlap. Parallel sections at both sides of the river could be linked by isolines following the topography parallel to the river, resulting in a continuous gallery forest belt (width between 10 and 30 m) flanked by savanna. Tree species typical for gallery forests have wider areas of distribution than savanna species. 相似文献