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1.
Abstract  The Lower Palaeozoic biostratigraphic records in the Alps are briefly reviewed and the result of a new study of the acritarch assemblage found by Sassi et al. (1984) in the greenschist facies black metapelites of the Southalpine metamorphic basement at Col di Foglia, and studied by Kalvacheva et al. (1986), is presented. The new  taxonomic and biostratigraphic study indicates a late Cambrian age, which is the oldest unquestionable, recently assessed, biostratigraphic dating of the entire Alps, as well as of the Italian peninsular. Keywords Alps, Southalpine metamorphic basement, Eastern Alps, Agordo, Acritarchs, Cambrian Subject codes: G17002  相似文献   

2.
Abstract

An Atlantic relict on the Apuan Alps: Trichomanes speciosum Willd., new to Italy.—In Versilia, at the foot of the Apuan Alps, has been found the fern Trichomanes speciosum Willd., new genus for the Italian flora and old relict witness, like Hymenophyllum tunbrigense (L.) Smith, of an Atlantic climate which still persists in deep valleys, dug on paleozoic quartz schists, on the tirrenic coast of the Apuan Alps.  相似文献   

3.
Abstract

Festuca alpestris R. et S. in the Alps near Belluno.—Some populations of Festuca from the F. varia aggr. occurring in the south-eastern Alps near Belluno have been recognized as belonging to F. alpestris R. et S. The relationships between this species and F. calva (Hackel) Richter from the Julian Alps are discussed and the diacritic characters are newly defined.  相似文献   

4.
Abstract

Lembotropis emeriflorus (Rchb.) Skali?ka in the Carnian Alps too.—Lembotropis (=Cytisus) emeriflorus, endemic species between the lakes of Lugano and Como, occurs also in the Southern Carnian Alps, where it grows either on gravelly habitats or on rocky slopes or under Austrian pine woods of the mountain zone. After this discovery its distributional pattern is now a typical bicentric one.  相似文献   

5.
TheSeslerio-Caricetum sempervirentis and theCaricetum ferrugineae from the Northern Calcareous Alps show considerable ecological and regional variation. 412 relevés representing both communities were classified by cluster analysis. Several subassociations and variants were distinguished and interpreted principally in terms of ecology and geographical distribution.  相似文献   

6.
Abstract

A syntaxonomic and phytogeographic delimitation of the calcareous open sedge swards in the alpine belt of the Alps (Caricion firmae) and subalpine and alpine tussock grasslands in wind-exposed habitats (Seslerion juncifoliae) in the area of the south-eastern Alps and of the Dinaric mountains was performed. Analyses based on hierarchical classification, ordination and chorology clearly showed the distinction between the syntaxa: stands from the Liburnian karst (Mt Sne?nik – SW. Slovenia, Mts Risnjak and Snje?nik – NW. Croatia), Li?ka Plje?ivica and the Velebit mountains belong to the Dinaric alliance Seslerion juncifoliae, whereas stands from the Trnovski gozd plateau (W. Slovenia, north-westernmost part of the Dinaric mountains), although somewhat transitional between the two alliances, and stands from the Alps, were classified in the alliance Caricion firmae. The alliance Seslerion juncifoliae of the Dinaric mountains vicariates Caricion firmae of the Alps.  相似文献   

7.
Background: Previous studies have indicated that several plant species had shown remarkable resistance to Pleistocene climate changes and survived the Last Glacial Maximum in scattered ice-free refugia within the European Alps and peripheral areas nearby. The ‘Expansion–Contraction’ model has been proposed to describe the responses of organisms to Pleistocene climate change. Nevertheless, the timing and extent to which species were affected by Quaternary glaciations remain uncertain.

Aims: To test whether the ‘Expansion–Contraction’ model appropriately describes plant distribution responses to Pleistocene climate change in the Western Alps.

Methods: We employed two Bayesian coalescent-based methods on plastid DNA sequences to infer the demographic histories of Ranunculus kuepferi, R. glacialis, Biscutella laevigata, Saxifraga oppositifolia, Primula allionii, P. marginata, Silene cordifolia and Viola argenteria.

Results: R. kuepferi conformed to the ‘Expansion–Contraction’ model, while other species did not. For example, P. allionii showed an alarming population decline during the Middle-Late Pleistocene.

Conclusions: The application of Bayesian coalescent-based methods to plastid DNA data offers useful insights into plant demography as a function of palaeoclimatic events. Our findings favour an idiosyncratic response of plant species in the Western Alps to Pleistocene climate change.  相似文献   

8.
Abstract

An interesting discovery in the Maritim Alps flora. ARTEMISIA CAMPHORATA Vill. with galls of DIARTHRONOMYIA KIEFFERI Trotter. Its geographical distribution and phytogeographical analysis. — The Author signals the finding, in the Maritim Alps flora, of some stations of an interesting discovery: Artemisia camphorata Vill. with galls of Diarthronomyia (Rhopalomyia) Kiefferi Trotter, and explains the characteristics of this Cecidomyide, (gall-midge).

He exhibits the results obtained through inquiries (investigations) directed to define the geographical area of Diarthronomyia Kiefferi, in reference to that of its host plant, of which the zoocecidium is exclusive.

The author makes also a map of the area and analyses the phytogeographical characte ristics and the mediterranean physiognomy of the new found stations.  相似文献   

9.
Two new species of the Empis (Leptempis) rustica group are described: E. (L.) tenuis n. sp. and E. (L.) lauriauti n. sp. Both were mainly collected in mountainous areas of the Mediterranean basin; the first species was collected in Morocco and Southern Spain; the latter was found in late summer in the Southern Alps in France. The key to species of the Empis (L.) rustica group is updated to include these two new species as well as a recently described Caucasian species.  相似文献   

10.
Vittoz P., Selldorf P., Eggenberg S. and Maire S. 2005. Festuca paniculata meadows in Ticino (Switzerland) and their Alpine environment. Bot. Helv. 115: 33–48.Festuca paniculata (L.) Schinz & Thellung locally dominates montane and subalpine meadows of the Alps and other mountains of southern Europe. Vegetation relevés were carried out in Switzerland and northern Italy to study the site conditions under which Festuca paniculata meadows occur in this part of the Alps, their species composition and phytosociological status, and their relationship to Festuca paniculata meadows described previously from the French Alps (Centaureo-Festucetum spadiceae) and Austrian Alps (Hypochaerido uniflorae-Festucetum paniculatae). The Swiss meadows were found to have a similar ecology to those in France and Austria. They occur mostly between 1600 and 2100 m a.s.l on steep slopes with southern aspect, generally on crystalline rocks, but sometimes on calcareous rocks if soils have been decalcified. The species composition of the Swiss meadows is closer to the Austrian than to the French communities, and we attribute them to the association Hypochaerido uniflorae-Festucetum paniculatae with the new subassociation polygaletosum chamaebuxi. Climate is probably the main factor separating vegetation units in the Alps: the Centaureo-Festucetum spadiceae occurs where summers are dry, whereas the Hypochaerido uniflorae-Festucetum paniculatae occurs where rainfall is not a limiting factor in summer.Manuscrit accepté le 10 février 2005  相似文献   

11.
Abstract

Centaurea forojuliensis, sect. Jacea DC. s. str., new entity from Friuli.—The new endemic entity Centaurea forojuliensis present in the marshes of Friuli (Northeastern Italy), is described. It is probably an ecotypical differentiation inside the polymorphic cycle of Centaurea Jacea due to the particular habitat. A taxonomic account of the whole cycle in the Southeastern Alps and Northadriatic carstic regions is also given.  相似文献   

12.
Serpentine soils harbour a unique flora that is rich in endemics. We examined the evolution of serpentine endemism in Minuartia laricifolia, which has two ecologically distinct subspecies with disjunct distributions: subsp. laricifolia on siliceous rocks in the western Alps and eastern Pyrenees and subsp. ophiolitica on serpentine in the northern Apennines. We analysed AFLPs and chloroplast sequences from 30 populations to examine their relationships and how their current distributions and ecologies were influenced by Quaternary climatic changes. Minuartia laricifolia was divided into four groups with a BAPS cluster analysis of the AFLP data, one group consisted only of subsp. ophiolitica, while three groups were found within subsp. laricifolia: Maritime Alps, north‐western Alps and central Alps. The same groups were recovered in a neighbour‐joining tree, although subsp. ophiolitica was nested within the Maritime Alps group of subsp. laricifolia. Subspecies ophiolitica contained three different chloroplast haplotypes, which were also found in the Maritime Alps group of subsp. laricifolia. Given its high genetic diversity, subsp. ophiolitica appears to have arisen from subsp. laricifolia by vicariance instead of by long‐distance dispersal. Genetic and geographic evidence point to the Maritime Alps populations of subsp. laricifolia as the closest relatives of subsp. ophiolitica. We hypothesize that M. laricifolia was also able to grow on nonserpentine rocks in the northern Apennines during glacial periods when the vegetation was more open, but that only the serpentine‐adapted populations were able to persist until the present due to their competitive exclusion from more favourable habitats.  相似文献   

13.
Abstract

The Maritime Alps are one of the ‘hot spots’ in the Mediterranean basin. This study investigated two endemic plants, Moehringia lebrunii and Moehringia sedoides (Caryophyllaceae) in order to increase knowledge of the vegetation of this region, and to investigate possible conservation strategies. Ecogeographic surveys and molecular analyses were undertaken. Gene diversity, the Shannon index and GST were calculated within and among populations of the two species based on ISSR data. The populations of M. lebrunii had a density ranging between 0.04 and 0.86 individual/m2 and a rather low inner genetic variability value. According to IUCN Red List Criteria, the current status of M. lebrunii is Endangered [EN B2ab(ii, iv)]. M. sedoides is an endemic of the SW Alps (not exclusive of the Maritime Alps), and is very abundant within the core of the range. Its range of occurrence is smaller than previously reported; nevertheless, the species is not under threat. This taxon showed a population density ranging between 0.03 and 0.58 individual/m2. Genetic variability values revealed a high variation among the species. Only peripheral populations seemed to suffer from their segregated position. Thus, M. sedoides is to be considered Critically Endangered [CR B1ab(i, ii, iii, iv) + 2ab(i, ii, iii, iv)] for Italy according to Regional Guidelines.  相似文献   

14.
Alyssum ovirense (Brassicaceae) is disjunctly distributed in the eastern Alps, predominantly occurring in the southern limestone Alps, but with one isolated population on the Hochschwab massif in the northern limestone Alps. The closely related rare and narrow endemic A. wulfenianum is restricted to gravel beds in a few rivers in the southern Alps draining the distribution area of A. ovirense. Applying molecular (amplified fragment length polymorphism fingerprinting and sequencing of plastid and nuclear DNA), karyological (flow cytometry and chromosome counts) and morphometric methods to a set of populations sampled throughout the distribution range, we evaluated the status of the population on the Hochschwab massif and the relationship between high‐elevation A. ovirense and low‐elevation A. wulfenianum. The population on Hochschwab massif is hexaploid, morphologically clearly divergent and grows in vegetation patches and dense alpine grasslands, whereas southern Alpine A. ovirense inhabits sparsely vegetated limestone screes. Molecular data show that the former represents a genetically isolated lineage which is formally described as A . neglectum sp. nov. All populations from the southern limestone Alps, including A. wulfenianum, are diploid. Although A. wulfenianum is genetically nested in A. ovirense, its morphological and ecological differentiation justifies recognition at the subspecific level. As A. wulfenianum has priority over A. ovirense, the correct names are A. wulfenianum subsp. wulfenianum and A. wulfenianum subsp. ovirense. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176 , 486–505.  相似文献   

15.
Abstract

TRINIA DALECHAMPII in the Illyric component of the Flora of the Apuan Alps. — On a mountaintop in the Apuan Alps, the author found Trinia dalechampii, an Illyric entity known until now in Ytaly only in the central and southern Apennines. He also indicates that a Greco-Apennine Oligo-Miocene bridge was the probable migration-route of this species and likewise of the Illyric entities of the Apennines.  相似文献   

16.
《Journal of bryology》2013,35(3):195-209
Abstract

Hymenostylium xerophilum is described as a new species from the European Alps. Molecular rps4 and ITS data support its recognition and elucidate its affinities to other species of the tribe Pleuroweisieae. It is closely related to H. gracillimum, comb. nov., which is based on the old and neglected Gymnostomum gracillimum, which replaces the recent name G. boreale. Both species share non-coloured to pale yellowish-brown rhizoids, stem central strand and indistinct sclerodermis, keeled leaves, and concave laminae in abaxial view. They differ from each other in leaf shape and several essentially quantitative characters. Sporophytes have never been found in H. xerophilum, but they are known from several localities in H. gracillimum. The former colonizes rather dry, sunny to half-shaded calcareous rocks, whereas the latter needs moist and shaded rock habitats and shows a preference for subneutral slate. At present, H. xerophilum is known only from the Alps (Austria, and a single site in Germany), where it is rather widespread in calcareous regions. H. gracillimum seems to be a distinctly rarer plant, to date known only from eight Austrian sites and one locality in Russian Karelia. Other published records under the name G. boreale have been wrongly attributed to this species. Lectotypes are designated for G. gracillimum and Gyroweisia acutifolia. A key to Hymenostylium and the genera of Pleuroweisieae in Europe is presented.

Thicker rhizoids of both species are covered with a thick, non-coloured protective layer and filled with oil-droplets and leucoplasts. They represent a subterranean secondary protonema, which plays an important role in the survival and propagation of these mosses, vital especially in the case of the non-sporulating H. xerophilum.  相似文献   

17.
Abstract

Chromatic variability of tepals in species of Crocus L. of South-eastern Alps.—The anthocyanidins causing the color of tepals of some species of Crocus L. in the Italian South-eastern Alps were determined and characterized. The genus Crocus of this region is represented by four entities: C. napolitanus Mord. & Loisel., C. albiflorus Kit. ex Schult., C. reticulatus Stev. ex Adam. and C. weldenii Hoppe ex Baker.

The distribution of anthocyanidins in the four entities confirms the existence of a systematic distance among the species belonging to Reticulati and the species belonging to Anulati. Two anthocyanidins, i.e. delphynidin and petunidin, which are always present in other entities, have not been found in C. weldenii; this species is characterized by the only presence of malvidine.

The anthocyanidins assume therefore in this case a chemotaxonomic meaning.  相似文献   

18.
《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   

19.
Michalet  R.  Rolland  Ch.  Joud  D.  Gafta  D.  Callaway  R.M. 《Plant Ecology》2003,165(2):145-160
Spatialassociations among overstory and understory species tend to increase ongradients from wet to dry climates. This shift in the strength of spatialassociations has usually been attributed to shared abiotic requirements betweencanopy species and understory assemblages within communities and/or to anincrease in habitat heterogeneity in dry climates and therefore higher betadiversity. On another hand, more important positive effects of tree canopies onunderstory species in drier climates may also explain stronger associations andhigher beta diversity. We examined these three hypotheses along a strongrainshadow gradient that occurs from the wet external Alps to the dry innerAlpsby analyzing with correspondence analysis and canonical correspondence analysisthe species composition of 290 relevés of forests dominated to differentdegrees by Abies alba and Piceaabies.We found important differences in climatic requirements forAbies and Picea, withAbies occurring in warmer and drier habitats thanPicea. The understory species associated with these twospecies showed similar correlations with temperature but not with moisture,withunderstory species of Picea-communities having strongerxeric affinities than understory species ofAbies-communities. We found no significant associationsbetween canopy species and understory composition in the external Alps despitethe fact that Abies and Piceaoccurredin substantially different environments. In contrast,Abiesand Picea occurred in more similar environments in theinner Alps, but the understory assemblages associated with eitherAbies or Picea were significantlydifferent. This increase in canopy-understory associations was in partdetermined by strong differences in moisture between southern and northernaspects in the inner Alps, which affected both canopy and understory speciesdistributions. However, differences between the canopy effects ofPicea and Abies also appeared tocontribute to stronger associations between canopy and understory species, andconsequently to increase beta diversity. This pattern only occurred on southernaspects of the inner Alps but was highly significant. Our results suggest thatspecies distributions may be continuous on the wet ends of moisture gradientsbut discrete on dry ends. Relatively discrete communities at stressful ends ofgradients appear to develop as a result of both habitat differentiation and thepositive effects of overstory species.  相似文献   

20.
This paper illustrates the phylogeographical structure of Saxifraga callosa in order to describe its genetic richness in refugial areas and to reconstruct its glacial history. S. callosa is a species spread throughout south-east France and Italy with a high distribution in the Maritime Alps. Four chloroplast microsatellite and AFLP markers were analyzed in populations of S. callosa. The size variants of all tested loci amount to 11 different haplotypes. Intrapopulational haplotype variation was found in two of the populations analyzed: on the Mt. Toraggio in the Maritime Alps, and in the Apuan Alps. On the other hand, no intrapopulational variation was found in 25 populations, most of which were sampled from isolated areas. Analysis of the haplotype distribution showed that population subdivision across all populations was high (G ST = 0.899). Moreover, its genetic structure was studied using AMOVA and STRUCTURE analysis. The study legitimated inferred conclusions about the phylogeographical structure of the species and identified centers of diversity. Considerations concerning genetic structure and divergence among three major clades (Maritime Alps, Apuan Alps and Apennines), the patchy distribution of haplotypes, and the high number of private haplotypes support the proposal that S. callosa survived in some refugia within the Italian Peninsula refugium, and that mainly northern populations of refugia were involved in postglacial recolonization.  相似文献   

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