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1.
H. Dierschke 《Plant Ecology》1985,59(1-3):171-175
Several central European species have failed to reach the British Isles because of the early separation from the continent. The two tree species Fagus sylvatica and Carpinus betulus reached southern England but were unable to spread much further. Other species, such as Acer pseudoplatanus, were only relatively recently introduced. Recent distribution maps for Fagus and Acer show an almost uninterrupted distribution in the whole British Isles. The beech must be considered to be an important element of the present potential natural vegetation; it has been planted widely and regenerates freely. The woodlands of Brittany may provide a model to enable us to visualize the possible species composition and appearance of these potential Atlantic beech woods.Nomenclature of vascular taxa follows Ehrendorfer (1973).  相似文献   

2.
The geographical relationships of British and Irish vascular plants   总被引:19,自引:0,他引:19  
Classifications of British and Irish vascular plants into floristic elements are reviewed. Only H.C. Watson and J.R. Matthews have attempted to devise a more or less comprehensive classification, based on the British range of the species (Watson) or the European distribution (Matthews). A new classification of 1481 native species is presented, based on their range in the Northern Hemisphere. Species are classified by their occurrence in one or more major biomes (Arctic, Boreal, Temperate, Southern) and their longitudinal distribution (Oceanic, Suboceanic, European, Eurosiberian, Eurasian, Circumpolar). The distribution of species in the floristic elements is illustrated by coincidence maps for the British Isles and Europe. The British and Irish flora is dominated by Boreo-temperate, Temperate and Southern-temperate species, with the Temperate species being the most numerous. Species with continental distributions (i.e. species which are rarer than expected in western Europe) are listed; most of these are in the Boreo-temperate and Temperate elements. The floristic elements are discussed in relation to the life-form spectra, habitat preferences and altitudinal limits of the component species, and analysed in terms ol˜ Ellenberg indicator values for temperature and continentality. The new classification is compared with that of Matthews. An additional 48 species which are endemic to the British Isles are listed. The scope for extending this method of classification to other organisms and for adapting it for use outside the British Isles is discussed.  相似文献   

3.
The scarcer freshwater fishes of the British Isles   总被引:1,自引:0,他引:1  
This, the first of two papers on the scarcer freshwater fishes of the British Isles, gives an account of the introduced species. Nineteen species are included. The natural distribution of these fishes, the history of their introduction, their success in acclimatization, and their present distribution in the British Isles are given. A brief discussion on the introduction of exotic fishes to aquatic ecosystems follows.  相似文献   

4.
Mine spoils and other soils contaminated with cadmium, copper, lead and zinc show natural colonization by species which have strategies of avoidance or tolerance of metal toxicities. The distribution of plants on such substrata in the British Isles is examined in the light of present knowledge of such strategies. Evolutionary processes mediating the selection of tolerant individuals and ecotypic differentiation of adapted populations on metalliferous soils are considered. Other factors determining which species can and which cannot evolve tolerance include constitutional differences in species sensitivity to toxic metals, and phenotypic (environmentally-induced) tolerances. The importance of constitutional properties and phenotypic responses in providing explanations for plant distribution on metalliferous soils is assessed.  相似文献   

5.
The biogeography of the western Palearctic has been intensively studied for more than a century. Recent advances in genetics have allowed the testing of old theories based on distribution patterns, although these analyses are obviously restricted to a reduced number of specific genetic data sets. On the other hand, an increased knowledge on the distributions of species and advances in computer capacities have allowed more detailed biogeographical analyses based on species presence/absence. In the present study, we selected the Odonata as the study group. For all 162 species native to the western Palearctic, we compiled their respective presence or absence in 97 predefined biogeographical regions. Using cluster analyses and principal component analyses, both based on Jaccard similarity coefficients, we analysed the differentiation among these regions and species. In subsequent analyses, the data set was reduced to the Zygoptera, Anisoptera, and the western Palearctic endemics. All analyses consistently showed different faunal regions and faunal elements. In particular, the (1) western and (2) eastern Mediterranean; (3) Central and (4) Northern Europe; and (5) the British Isles were invariably found in all cases. Although the two major Mediterranean regions were characterized by several endemic faunal elements, Northern Europe and the British Isles lacked such elements, but were characterized by faunal compositions strongly deviating from the rest of the western Palearctic region. Moderate differences between Zygoptera and Anisoptera existed, with the latter more clearly redrawing the Mediterranean refuge areas, whereas the former reflected to a greater extent the postglacial expansion patterns from these regions. In general, our findings underline the old biogeographical theories, but refine especially our understanding of the Atlanto‐ and Ponto‐Mediterranean region. Central Europe, comprising the area with the highest species numbers of our whole study region, unravels as a crossroad of postglacial immigrations, but might also represent a region of in situ glacial survival. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 177–195.  相似文献   

6.
A Y chromosome census of the British Isles   总被引:7,自引:0,他引:7  
The degree of population replacement in the British Isles associated with cultural changes has been extensively debated. Recent work has demonstrated that comparisons of genetic variation in the British Isles and on the European Continent can illuminate specific demographic processes in the history of the British Isles. For example, Wilson et al. used the similarity of Basque and Celtic Y chromosomes to argue for genetic continuity from the Upper Palaeolithic to the present in the paternal history of these populations (see also ). Differences in the Y chromosome composition of these groups also suggested genetic signatures of Norwegian influence in the Orkney Islands north of the Scottish mainland, an important center of Viking activities between 800 and 1300 A.D. More recently, Weale et al. argued for substantial Anglo-Saxon male migration into central England based on the analysis of eight British sample sets collected on an east-west transect across England and Wales. To provide a more complete assessment of the paternal genetic history of the British Isles, we have compared the Y chromosome composition of multiple geographically distant British sample sets with collections from Norway (two sites), Denmark, and Germany and with collections from central Ireland, representing, respectively, the putative invading and the indigenous populations. By analyzing 1772 Y chromosomes from 25 predominantly small urban locations, we found that different parts of the British Isles have sharply different paternal histories; the degree of population replacement and genetic continuity shows systematic variation across the sampled areas.  相似文献   

7.
A new taxonomic treatment of the Festuca ovina L. aggregate (Poaceae) in the British Isles. A wide range of morphological, anatomical and cytological characters was collected and analysed by a variety of methods, some taxometric. As a result nine species are recognized in the British Isles, one (F. glauca Vill.) only as a garden plant and two (F. huonii Auquier and F. armoricana Kerguélen) only in the Channel Isles. Two other species sometimes claimed for the British Isles (F. guestfalica Boenn. ex Reichb. and F. indigesta Boiss.) are excluded for various reasons given. One species (F. ovina L.) is divided into three subspecies: the diploid subsp. ovina (commonest in the north); and the tetraploid subsp. hirtula (Hackel ex Travis) M. Wilkinson (the commonest taxon of the aggregate in the British Isles) and subsp. ophioliticola (Kerguélen) M. Wilkinson (scattered throughout the British Isles, but commonest on chalk and limestone and not restricted to serpentine soils as once thought).  相似文献   

8.
Because species concepts change and world distributions come to be better known, our picture of bryophyte distribution is subject to continual revision. Herzog's masterly phytogeographical analysis is cited as representative of the situation midway between Holmes's time and the present day. The modern position is reviewed, both for the British Isles and on a world-wide scale. The link between taxonomic revisions and distributional studies is explored. The many recent contributions to our knowledge of bryophyte distribution are classified under several distinct heads. Attention is focussed on selected genera of outstanding interest. Finally, brief consideration is given to the wider implications of the various types of distribution study.  相似文献   

9.
The geographical distribution of the red alga Pterosiphonia complanata (Clem.) Falkenb. is described. New records confirm that it is restricted to the warmer waters of the North Atlantic and extend its known distribution in the British Isles where it is at the northern limits of its range. The apparent scarcity and restricted distribution of the species in the British Isles and the absence of sexual plants throughout its range are discussed in relation to the habitat and possible life history of the species.  相似文献   

10.
D. W. Snow 《Ibis》1953,95(2):242-270
This paper aims to bring together the chief observations that have been recorded so far on visible migration in the British Isles.
The autumn movements that have been seen on the various coasts, and inland, are briefly described, and the few spring observations are summarized.
Maps show the directions which migrating Corvidae, Starlings, Chaffinches and Skylarks have been seen to take in autumn, and there is some discussion of the autumn movements of these four species. The observed movements of some of the other chief passerines, and of the Wood-pigeon, Stock-dove and Lapwing, are more briefly mentioned.
Some of the differences in the migratory behaviour of different species are mentioned, and some of the most obvious gaps in knowledge of visible migration in the British Isles are pointed out.  相似文献   

11.
West Nile virus (WNV) transmitted by mosquitoes (Diptera: Culicidae) infects various vertebrates, being pathogenic for birds, horses and humans. After its discovery in tropical Africa, sporadic outbreaks of WNV occurred during recent decades in Eurasia, but not the British Isles. WNV reached New York in 1999 and spread to California by 2003, causing widespread outbreaks of West Nile encephalitis across North America, transmitted by many species of mosquitoes, mainly Culex spp. The periodic reappearance of WNV in parts of continental Europe (from southern France to Romania) gives rise to concern over the possibility of WNV invading the British Isles. The British Isles have about 30 endemic mosquito species, several with seasonal abundance and other eco-behavioural characteristics predisposing them to serve as potential WNV bridge vectors from birds to humans. These include: the predominantly ornithophilic Culex pipiens L. and its anthropophilic biotype molestus Forskal; tree-hole adapted Anopheles plumbeus Stephens; saltmarsh-adapted Ochlerotatus caspius Pallas, Oc. detritus Haliday and Oc. dorsalis (Meigen); Coquillettidia richiardii Ficalbi, Culiseta annulata Schrank and Cs. morsitans (Theobald) from vegetated freshwater pools; Aedes cinereus Meigen, Oc. cantans Meigen and Oc. punctor Kirby from seasonal woodland pools. Those underlined have been found carrying WNV in other countries (12 species), including the rarer British species Aedes vexans (Meigen), Culex europaeus Ramos et al., Cx. modestus Ficalbi and Oc. sticticus (Meigen) as well as the Anopheles maculipennis Meigen complex (mainly An. atroparvus van Thiel and An. messeae Falleroni in Britain). Those implicated as key vectors of WNV in Europe are printed bold (four species). So far there is no proof of any arbovirus transmission by mosquitoes in the British Isles, although antibodies to Sindbis, Tahyna, Usutu and West Nile viruses have been detected in British birds. Neighbouring European countries have enzootic WNV and human infections transmitted by mosquito species that are present in the British Isles. However, except for localized urban infestations of Cx. pipiens biotype molestus that can be readily eliminated, there appear to be few situations in the British Isles where humans and livestock are exposed to sustained risks of exposure to potential WNV vectors. Monitoring of mosquitoes and arbovirus surveillance are required to guard the British Isles against WNV outbreaks and introduction of more anthropophilic mosquitoes such as Stegomyia albopicta (Skuse) and Ochlerotatus japonicus (Theobald) that have recently invaded Europe, since they transmit arboviruses elsewhere.  相似文献   

12.
Aim Ecologists seeking to describe patterns at ever larger scales require compilations of data on the global abundance and distribution of species. Comparable compilations of biological data are needed to elucidate the mechanisms behind these patterns, but have received far less attention. We assess the availability of biological data across an entire assemblage: the well‐documented demersal marine fauna of the United Kingdom. We also test whether data availability for a species depends on its taxonomic group, maximum body size, the number of times it has been recorded in a global biogeographic database, or its commercial and conservation importance. Location Seas of the United Kingdom. Methods We defined a demersal marine fauna of 973 species from 15 phyla and 40 classes using five extensive surveys around the British Isles. We then quantified the availability of data on eight key biological traits (termed biological knowledge) for each species from online databases. Relationships between biological knowledge and our predictors were tested with generalized linear models. Results Full data on eight fundamental biological traits exist for only 9% (n= 88) of the UK demersal marine fauna, and 20% of species completely lack data. Clear trends in our knowledge exist: fish (median biological knowledge score = six traits) are much better known than invertebrates (one trait). Biological knowledge increases with biogeographic knowledge and (to a lesser extent) with body size, and is greater in species that are commercially exploited or of conservation concern. Main conclusions Our analysis reveals deep ignorance of the basic biology of a well‐studied fauna, highlighting the need for far greater efforts to compile biological trait data. Clear biases in our knowledge, relating to how well sampled or ‘important’ species are suggests that caution is required in extrapolating small subsets of biologically well‐known species to ecosystem‐level studies.  相似文献   

13.
Aim To compare the wider distribution of the pteridophytes, flowering plants, liverworts and mosses recorded as natives of Britain and Ireland, and to assess the proportion and distribution of species in each group which belong to predominantly extra-European genera. Location The species native to the British Isles are considered in relation to their distribution in the Northern Hemisphere, and predominantly extra-European genera are identified by consideration of the distribution and centre of numerical diversity of the genera worldwide. Methods A recent classification of the pteridophytes, flowering plants, liverworts and mosses into floristic elements is used in a quantitative study of the distribution of species in the four groups, the patterns of occurrence being compared by standardized residuals. Results Mosses and liverworts have more northerly distributions than the flowering plants in the Northern Hemisphere; pteridophytes show an intermediate pattern. There are marked differences in the longitudinal ranges of the groups south of the Boreal biome, with vascular plants tending to be confined to Europe or western Eurasia whereas cryptogams are more likely to occur additionally in North America or have a circumpolar distribution. The proportion of predominantly extra-European genera is particularly high in the pteridophytes and the liverworts and in these groups the rich hyperoceanic flora of the British Isles is almost entirely composed of species in genera that attain their centre of diversity in the tropics. Main conclusions Major taxonomic groups show different distribution patterns, reflecting their rates of evolution and powers of dispersal. The flowering plants, as the least mobile and most rapidly evolving group, have a greater proportion of their species in the European and Eurosiberian elements and a higher proportion of species from extra-European genera in the more northerly elements.  相似文献   

14.
Generalizations about rare and endangered species are important for the development of conservation management policy and for understanding of the nature of rarity. Therefore, we sought such generalizations by statistically comparing eight life history and reproductive traits of rare and common plant species in two better-studied but climatically and geographically distinct Holarctic floras-those of California and the British Isles. Trends were often similar in both floras. Rare and common species differ significantly for a number of characters. In both floras, a woody habit was significantly more frequent for the rare species than the common species. Also, in both floras, monocarpy was less frequent in the rare species, significantly so in California. The rare species of both floras were, on average, significantly shorter in stature than the common species. This trend in stature remained significant when nonwoody species were compared but did not do so for woody species. Rare and common species differed with regard to their frequency of inflorescence structure types, but these differences were not concordant for both floras. The rare species of the British Isles had significantly higher proportions of mixed and polymorphic flower colors; the trend was not significant in California. In both floras, rare species had a higher frequency of many-seeded fruits, significantly so in California. California's rare species had a significantly higher frequency of dehiscent fruits than common species; the trend was reversed and not significant for the British Isles. We found no significant differences for characters associated with fruit dispersal. Finally, in California, the median altitude of the range of the common species was significantly greater than that of the rare species. At present, these correlates cannot be assigned as possible causes or consequences of rarity. Nonetheless, they may represent "high-risk" traits that could be used to identify other species already at risk or potentially at risk of becoming rarer.  相似文献   

15.
The giant earthworm, Rhinodrilus alatus (Righi 1971), has been captured in the southeastern Brazilian Cerrado biome for approximately 80 years and used as bait for amateur fishing throughout Brazil. Local knowledge and traditional extraction practices are crucial for the establishment of management strategies for the species because, although its extraction involves conflicts and social and environmental impacts, the species is one of the major sources of income for approximately 3,000 people, especially for members of an Afro-descendant community that has approximately 2,000 inhabitants. Participatory tools, such as seasonal calendar, transect walks and participatory maps, were individually or collectively used with extractors and traders (former extractors), and 129 semi-structured and unstructured interviews were conducted with the same individuals between 2005 and 2012. The capture of Rhinodrilus alatus was observed in different seasons and areas of occurrence of the species in 17 municipalities, where this giant earthworm is the only species extracted for trade. All information obtained was verified by community members in 17 meetings. The extractors have an extensive knowledge of the life history, behavior, distribution, and possible impacts of climate change on the species. Different capture techniques, which have different impacts, are used during the dry and rainy seasons and are passed by the extractors through the generations. Local knowledge contributed to the establishment of agreements for the use of capture techniques that have less impact, to the expansion of scientific knowledge and the reassessment of the conservation status of Rhinodrilus alatus. The present study may serve as an example for management projects for other giant earthworm species in other regions of Brazil and in other countries.  相似文献   

16.
The distribution of malaria vector mosquitoes, especially those belonging to species complexes that contain non-vector species, is important for strategic planning of malaria control programmes. Geographical information systems have allowed researchers to visualize distribution data on maps together with environmental parameters, such as rainfall and temperature. Here, Maureen Coetzee, Marlies Craig and David le Sueur review our current knowledge on the distribution of the members of the Anopheles gambiae complex.  相似文献   

17.
SUMMARY. The discovery of a third species of alderfly ( Sialis nigripes ) in Britain and Ireland necessitates a new larval key for the group in these islands. Characters are now provided to distinguish the larvae of the three species, and their habitat and distribution in the British Isles are outlined.  相似文献   

18.
The vertical distribution of benthic marine algae on a sublittoral cliff in the Isles of Scilly is described and briefly compared with that found in other parts of the British Isles.  相似文献   

19.
G. I. TWIGG 《Mammal Review》1980,10(4):139-149
The occurrence of the major zoonoses in British mammals is discussed. The distribution of leptospiral serotypes across the British Isles and North–West Europe, together with the current absence of rabies, plague and other pathogenic organisms in Britain suggests conditions inimical to their maintenance in the British Isles. It is suggested that this region may represent the end of a geographical line of success for these organisms and the term 'pathocline' is proposed.  相似文献   

20.
The species ofDermatocarponoccurring in the British Isles are reviewed, with special reference to the hydrophilous species; a number of related species not yet recorded for the British Isles are also briefly treated.Dermatocarpon deminuensandD. leptophyllodesare confirmed as British; the nameD. leptophyllumshould be deleted from the British list. The nameD. meiophyllumis shown to be based on discordant elements. A key is provided to the British and Irish species.  相似文献   

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