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1.
Capsule Redshank diet from southern Europe during migration shows spatial and seasonal variations. Aims To assess seasonal variation in Redshank diet at a major passage site, and to compare data derived from analysing pellets or faeces. Methods At the Odiel Marshes in 2001, pellets from spring migration (39), autumn migration (121) and midwinter (15) were analysed, together with faecal samples from autumn (84). Results The abundance of different invertebrate groups in pellets varied between seasons. In spring, Chironomus salinarius pupae and larvae dominated by volume, followed by Ephydridae larvae and the beetle Paracymus aenus. Polychaetes and molluscs dominated in autumn, and isopods in midwinter. In autumn, chironomid larvae, Mesembryanthemum nodiflorum seeds and Artemia cysts were relatively more abundant in faeces, whereas polychaetes, isopods, molluscs and cestode cysticercoids were more abundant in pellets. Harder and/or larger items were thus relatively more abundant in pellets than faeces. Pellet analysis gave more emphasis to mudflat prey, and faeces to saltpan prey. Conclusion Pellet and faecal analysis give different results for wader diet, and it is useful to combine the two methods. However, they show significant correlations both in diet range and rank abundance of prey items. Redshank diet shows much seasonal and spatial variation in southern Europe. 相似文献
2.
Background: The effect of the anticipated climate change on the stability of vegetation and the factors underlying this stability are not well understood. Aims: Our objective was to quantify long-term vegetation changes in a range of habitats in northern Europe by exploring species co-occurrences and their links to diversity and productivity gradients. Methods: We re-sampled vegetation in 16 arctic, mountain and mire sites 20 to 90 years after the original inventories. A site-specific change in species assemblages (stability) was quantified using species co-occurrences. Using a randomisation test we tested whether the changes observed were significantly greater than those expected by chance. Relationships between patterns in vegetation stability and time between surveys, numbers of plots, or species diversity and proxies for productivity, were tested using regression analysis. Results: At most sites the changes in species co-occurrences of vascular plants and bryophytes were greater than those expected by chance. The changes observed were found to be unrelated to gradients in productivity or diversity. Conclusions: Changes in species co-occurrences are not strongly linked to diversity or productivity gradients in vegetation, suggesting that other gradients or site-specific factors (e.g. land use or species interactions) may be more important in controlling recent compositional shifts in vegetation in northern Europe. 相似文献
3.
AbstractHaplotype variation is explored for Sarmentypnum exannulatum (Schimp.) Hedenäs, based on the nuclear ITS, and the chloroplast trnL– trnF, rpl16 and tRNA-Gly in 179 specimens (176 for chloroplast markers). The focus is Europe (124 samples), and especially Scandinavia (79), but most regions of the species' distribution area except northern Eurasia were sampled. Haplotype variation appears greater in Scandinavia than in Central Europe, with five of the European haplotype groups found only in Scandinavia compared with one unique to Central Europe. The Central European haplotype group probably survived the glaciations in one or several of the well-known refugia of the northern Mediterranean, but this seems unlikely for the Scandinavian haplotypes. The latter could have survived in northern refugia or immigrated from the east or north-east. On a global scale, several haplotype groups have restricted distributions, which could be due to sparse sampling in some regions, or the evolution or extinction of haplotypes. Some haplotypes were perfectly bipolar, whereas the species as a whole is imperfectly bipolar. These were absent from more southern parts of the northern temperate zone and from the sampled tropical mountains. It thus seems unlikely that representatives of these haplotypes dispersed from north to south (or vice versa) by stepwise migration. 相似文献
4.
Capsule Red-spotted Bluethroats Luscinia s. svecica from two European breeding populations spent the boreal winter on the Indian sub-continent. Aim Tracking the migration of Red-spotted Bluethroats from Europe to the hitherto unknown non-breeding areas and back. Methods Light-level geolocators were deployed on male Bluethroats at breeding sites in the Czech Republic ( n?=?10) and in Norway ( n?=?30). Recorded light intensity data were used to estimate the locations of non-breeding sites and migration phenology during the annual cycle. Results Bluethroats spent the boreal winter in India ( n?=?3) and Pakistan ( n?=?1), on average more than 6000?km from their breeding areas. Autumn migration started in August ( n?=?1) or early September ( n?=?2), and lasted for 26–74 days. Spring migration commenced on 8 and 9 April ( n?=?2) and lasted for about a month. During both autumn and spring migration, birds stopped over two or three times for more than 3 days. Conclusion This study for the first time showed where Red-spotted Bluethroats from European breeding populations stay during the boreal winter. This seems to be the first time that a passerine bird has been tracked along the Indo-European flyway. 相似文献
5.
AbstractThe bryophyte florash of 14 travertine-depositing sites in the French Alps and Britain were investigated and consisted of 34 taxa (26 mosses and eight hepatics), with the commonest species, Eucladium verticillatum and Palustriella ( Cratoneuron) commutata, occurring in both countries. Species richness ranged from 3-15 and was related mainly to site size and heterogeneity with respect to water flow. Bryophytes grew within or close to Ca-bicarbonate waters with base concentrations (HCO 3 ) ranging from 1.42 to 7.58 mM at pH 6.9-8.3. P. commutata sensu lato was found to extend to more northerly sites in Europe than E. verticillatum, although the two species were frequently present at the same site. Principal component analysis suggested that the distribution of P. commutata var. commutata was influenced more by temperature than water chemistry. 相似文献
6.
Capsule We report a review of the occurrence of bats in the Barn Owl diet Tyto alba in Europe. Based on 802 studies reporting 4.02 million prey items identified in pellets, 4949 were bats (0.12%). We found that bat predation decreased during the last 150 years, is more frequent on islands than mainland, and is higher in eastern than western Europe and in southern than northern Europe. Although Barn Owls usually capture bats opportunistically, they can sometimes specialize on them. 相似文献
7.
AbstractThe new combination Tetralophozia filiformis (Steph.) E. Urmi is proposed for Chandonanthus filiformis Steph. So far this species has been known only from Asia and N. America. Recent collections show it to occur also in Europe, in the Cantabrian Mts., Spain. Here it grows in sheltered places on siliceous rocks in oceanic conditions. From Tetralophozia setiformis (Ehrh.) Schljak. (= Chandonanthus setiformis) it is distinguished by its smaller size, the leaf lobes are always more than twice as long as wide and their margins are not inflexed towards the stem. 相似文献
8.
Capsule White-throated Dippers from southern Europe were found to be infected by three haemosporidians. Aims To examine the occurrence of blood parasites in dippers in the Iberian Peninsula and to investigate the relationship between prevalence levels, environmental factors and bird fitness. Methods White-throated Dippers were trapped with mist-nets from five montane areas in the centre of the Iberian Peninsula. Parasites were detected from blood samples by polymerase chain reaction screening. Results About half (51.3%) of 152 dippers showed some kind of infection. The genus Haemoproteus was recorded in 49.3% of the birds, and the genus Leucocytozoon in 19.1%, while Plasmodium was present only in 0.7%. Among the infected birds, 34.6% carried a double infection ( Haemoproteus?+? Leucocytozoon). Prevalence did not differ between gender or age-classes, but it varied between study sites, being significantly higher in mountains with higher precipitation. There was a reduction in body mass owing to double infection in yearling males only. Conclusion This is the first work assessing parasite prevalence in dippers from southern Europe. Infection of dippers by haemosporidians is likely to be related to a study site's climatic envelope. 相似文献
9.
AbstractThe taxonomy of Anomobryum julaceum and allied species with axillary bulbils in Europe and Asia is reviewed. A. concinnatum is regarded as a distinct species, occurring in W. and C. Europe, SW., N. and C. Asia and N. America. A. bavaricum has often been confused with A. concinnatum, but differs in its more numerous, small, reddish bulbils and in leaf shape; it is known only from the European Alps. The Asian A. nitidum also has numerous small reddish bulbils but it differs from A. bavaricum in leaf shape and bulbil form. A lectotype is designated for A. nitidum, of which A. gemmigerum and other nominal taxa are regarded as synonyms. Information is presented on geographical ranges and habitats of the four valid species. 相似文献
10.
AbstractThe few studies that have investigated levels of genetic variation in liverworts have found very little polymorphism. Our electrophoretic data show, however, that the leafy liverwort Porella platyphylla maintains high levels of genetic variation in at least some natural populations from the southeastern United States. Within a single population from southwestern North Carolina, we detected 26 distinct multilocus genotypes and more than 80% of the enzyme loci we surveyed were polymorphic. It seems likely that earlier studies of mostly thalloid species from glaciated regions of Europe have presented a biased picture of levels of variation in liverwort populations. 相似文献
11.
The cosmopolitan subfamilies Aphrodinae, Jassinae, Xestocephalinae, Idiocerinae, and Macropsinae are diagnosed and the New Zealand species described and illustrated. Each subfamily is represented in New Zealand by only one or two species, those in Idiocerinae having been introduced from Europe or North America. The species Euacanthella brunnea Evans (Aphrodinae) is synonymised with the Australian species E. insularis Evans (new synonymy). 相似文献
12.
Capsule All British Marsh Tits belong to subspecies Poecile palustris dresseri, being smaller than nominate P. p. palustris of central Europe. Aims Determining the subspecies of Marsh Tit in Britain to test whether ssp. P. p. palustris occurs in northern England and Scotland, by assessing regional variation in size compared with central European birds. Methods 1147 wing length and 250 tail length measurements from 953 Marsh Tits were compared between eight British locations to test for regional variation. Biometrics were compared between birds from Britain and six locations within the continental European range of ssp. palustris. Results There was no regional variation in wing or tail lengths among British Marsh Tits, indicating that all resident birds belong to ssp. dresseri. There was no evidence supporting the existence of ssp. palustris in northern England. British birds were significantly smaller than those from continental Europe, with proportionately shorter tails, consistent across all age and sex classes. Conclusion All British Marsh Tits should be considered as ssp. dresseri, with ssp. palustris being limited to continental Europe. With no evidence of regional variation in size within Britain, reliable sexing methods based on biometrics could be applied in demographic studies throughout the country. 相似文献
13.
Abstract Pohlia nutans subsp. schimperi is recognized as a distinct taxon, differing from ssp. nutans by the pink to purple coloration of its leaves and a dioicous or polyoicous, rather than paroicous, sexual condition. We review the contrasting reports about the sexuality of these plants, as well as their nomenclatural history, and demonstrate their synonymy with P. nutans subsp. purpurascens Latzel. The subspecies shows a mainly arctic–subarctic distribution, with relict Central European occurrences in the Eastern Alps, the Sudetes and the western Carpathians, probably reflecting migratory events during the Pleistocene. The ecology and phytosociological affinities of the taxon in Central Europe are discussed in detail. 相似文献
14.
Abstract Artioposthia triangulata was originally described from New Zealand in 1895 but was subsequently found to have spread to Northern Ireland in 1963 and Scotland and England in 1965. It is now widespread in both Ireland and Scotland, where it has been shown to reduce earthworm numbers to below detectable levels. Ecoclimatic data were used in the computer program CLIMEX to estimate the potential spread of A. triangulata to Europe and the rest of the world. Results indicated it could establish in agricultural land in most of north‐western Europe, and persist in domestic gardens throughout much of central Europe, east and west North America, Australia, southern South America, and South Africa. It is difficult to assess either the extent to which earthworm numbers and diversity would be decreased or how far the effect of their loss to soil structure, nutrient cycling, or wildlife would be detrimental in these areas. 相似文献
15.
Capsule Reverse migration in autumn does not occur to the same degree in all species of migrants, but is related to migratory direction. Aims To identify factors determining degree of reverse migration and specifically to test whether it occurs in long-distance migrant species irrespective of their standard (normal) migration direction. Methods Multiple regression analysis on the number of individuals occurring as reverse migrants observed in northwest European countries. Methods Multiple regression analysis on the number of individuals occurring as reverse migrants observed in northwest European countries. Results The number of reverse migrants observed in northwest European countries is strongly correlated with standard migratory direction, estimated population size and detectability, but an effect of the distance travelled from the breeding areas is not supported. The pattern holds true for subsamples of the data set, including British and Irish records or Scandinavian records only, and when controlling for phylogeny. Conclusion Birds that migrate eastward in autumn from their breeding grounds, mostly in eastern Europe, are more likely to consistently reverse migrate than those species migrating southward mostly from southern Europe. 相似文献
16.
Capsule The breeding success of Lesser Spotted Woodpeckers Dendrocopos minor is now lower in England than previously reported and also lower than found in studies elsewhere in Europe. Aims To quantify the breeding success and identify the causes of nest failure. To test the hypotheses that breeding success is related to aspects of food limitation and parental care, and inclement weather during the nesting period, or to interactions with Great Spotted Woodpeckers. Methods Nests were monitored in three regions of England, recording survival and causes of failure. We measured aspects of food limitation and parental care, rainfall and Great Spotted Woodpecker interactions at nests, to explore whether there was any evidence that these factors were related to breeding success. We compared results to other studies from the UK and continental Europe. Results Nest survival was 52%. The average number of chicks produced from successful nests was 2.8. Chick-stage daily nest survival was positively related to provisioning rates, indicating that food supply may be limiting. The most common cause of nest failure was presumed starvation of chicks after the disappearance of an adult. Some females ceased visiting nests, leaving provisioning solely to the male. This behaviour has been reported elsewhere in Europe, but in the present study males were unable to compensate fully by increasing their provisioning rates, leading to poor nest survival. Provisioning rates and chick-stage daily nest survival were negatively associated with rainfall. Nest predation by Great Spotted Woodpeckers occurred but was a less frequent cause of failure. Aggressive interactions were recorded between the two woodpecker species but these were unrelated to breeding parameters. Conclusions Low breeding success is most probably related to food shortages in the breeding period. Simple population modelling using parameters from the present study and from published work shows that if the low productivity that we have observed is replicated throughout Britain, it would be sufficient to account for the observed population decline. However, the possibility that survival rates are also low cannot be ruled out. 相似文献
17.
AbstractThe discovery of Paludella squarrosa (Hedw.) Brid., new to Ireland, is reported. This Boreo-arctic Montane species has a relic distribution in western and central Europe and was formerly more widespread. The reasons for its decline and its documented extinction from Britain and the Netherlands in recent times are discussed. The vegetation and ecology of the Irish locality are described. The associated species include Leiocolea rutheana, another Boreal relic species and a second record for Ireland. 相似文献
18.
Abstract Pseudoscleropodium purum, presently found scattered throughout the world, appears to be unquestionably indigenous only to Europe. Reports of its establishment on Tristan da Cuñha are in error; examination of the labels on duplicates of the single Argentinean collection raises the possibility that it originated in Europe. P. purum is newly reported from Chile. A distribution map of the species is provided. 相似文献
19.
Abstract A hypothesis on the evolution of Limonium species in the Mediterranean area. — The chromosomic somatic number of 27 species and 2 hybrids belonging to the genus Limonium (Plumbaginaceae) of several Mediterranean regions (Spain, France, Tuscany, Sardinia, Sicily) and Canarian Islands are here determined on wild populations. Keeping into account 10 data previously determined by other Authors, the chromosomic number is now known for more than 1/3 of the species occurring in West Europe and Mediterranean. This allows to formulate a hypothesis on the group's evolution: from some diploid species living on inner rocks (Felsenheide) or sea cliffs and having a very restricted area, tetraploid races living on sandy shores had developped, which expanded afterwards on the whole Mediterranean area, and finally by hybridations giving rise to triploids. Ecology and areal dimension of triploid species are generally intermediate between those of diploids and tetraploids; in some cases there is an apparent tendency to fragmentation into local forms, sometimes joined with apomictic reproduction. 相似文献
20.
Abstract. A geographic and taxonomic overview of the non-indigenous plant species of Europe, based on the ‘Flora Europaea’ is given. The flora of Europe includes 1568 species which have either expanded their ranges within Europe under human influence (naturalized European species) or are of non-European origin (exotic species). The latter group consists of 580 species (37%) which form a diverse group in terms of their taxonomic composition and geographic origin. The exotics are represented by 113 families, of which the Compositae, Rosaceae and Gramineae are most important. The ratio of species to families is low. Most exotic species in Europe originate from the Americas and Asia. Countries of southern Europe have a higher relative number of exotics in their non-native flora than northern ones. The species-range size distribution differs between naturalized European and exotic species; the latter are on average more widespread than the naturalized. 相似文献
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