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21.
With increasing pressures on land for human use, it is important to identify the habitat requirements of key species, not just in terms of a correlation with a given habitat feature, but also the relationship between species presence and its coverage, proximity to other habitat types, and importance at different spatial scales. We used maximum entropy to estimate the optimal proportions of 18 habitat types, plus elevation and habitat richness associated with the presence of leks of Black Grouse Tetrao tetrix within an 800‐km2 study area in Perthshire, Scotland. We repeated the analysis at several radii (0.2–3 km) to assess how the importance of different habitats changed with proximity to lek and scale. We then examined habitat features or combinations of features that were associated with large leks or positive lek growth. Models at all radii had satisfactory predictive power. Using response curves from maxent , we constructed ideal habitat mixes for leks at each radius. At the 2‐km radius, suitability was highest with around 20% each of three moorland types and open/mixed forestry, whereas close to leks (0.2 km), higher proportions of grouse moor and lower proportions of closed‐canopy woodland were optimal. The relationship between habitat and lek size or direction of lek growth was complex, indicating that a landscape containing large or productive leks can be the result of more than one combination of habitats. This demonstrates a degree of flexibility in designing landscapes for Black Grouse conservation, so landowners can prioritize combinations of habitats that are the most practical and/or economical, while still serving the requirements of the target species.  相似文献   
22.
This article re-examines how willing the English and Scots are to accept or reject claims to respective national identities by people born elsewhere. A previous paper showed, counter-intuitively, that people in the two countries were similar in their willingness to accept claims to national identity. Since then, different political parties are in power in England and Scotland, with differing policies and attitudes to identity. Have the original findings changed in the context of this significant political change? We conclude that the English and Scots continue to be similar on accepting or rejecting claims. However, they have diverged with regard to claims by white people, with national identity a less important explanatory variable than education in Scotland, whereas in England it remains the determining factor. For claims by non-whites, the two societies have become more similar. Education remains in Scotland, and to a considerable extent in England, the more important explanatory variable.  相似文献   
23.
Invertebrate and ciliate protozoan epibionts of velvet swimming crabs collected near Millport (Scotland) were analysed. The ecdysis peak for male crabs was at the time of collection while that for female crabs was 2 months later. The epibionts were: the polychaetes Pomatoceros triqueter and Hydroides norvegica, the cirriped Balanus crenatus, the entoproct Barentsia matsushimana, the hydroids Leuckartiara sp. and Clytia sp., and the ciliate protozoans Ephelota plana, Ephelota gemmipara, Chilodochona quennerstedti and Cothurnia longipes. The polychaetes, cirripeds, entoprocts and hydroids, all of them with comparatively larger size, were distributed on the carapace, ventral surface of the cephalothorax and the pereiopods; meanwhile the protozoans, with smaller size, were attached also on pleopods, antennae, eyes and buccal appendages. Chilodochona quennerstedti was the epibiont most abundant on the crab, followed by Ephelota plana. Cothurnia longipes was, in contrast, the least abundant epibiont, followed by Barentsia matsushimana. The anatomical unit most colonized was the left third maxilliped, followed by the left first maxilliped and the ventral surface. The less colonized anatomical units were the left antenna and the ocular orbits. Epibionts on this crab have not been described before. Statistical analyses of the epibiont distribution on the crab were carried out. There were significant correlations between right and left appendages in 66.67% of the cases. Males and females differed significantly with respect to the distribution of epibionts on their anatomical units. The comparison analysis indicated a significant differential distribution of each epibiont species on the anatomical units of the crab. Principal component analysis grouped the epibiont species according to their colonization pattern in three clusters: (1) Ephelota plana, Ephelota gemmipara and Chilodochona quennerstedti; (2) Leuckartiara sp., Clytia sp., Barentsia matsushimana and Cothurnia longipes; and (3) Pomatoceros triqueter, Balanus crenatus and Hydroides norvegica. The hierarchical cluster analysis grouped the anatomical units of the crab in relation to their colonization in five clusters.  相似文献   
24.
Recently, linkage of a DNA microsatellite marker to inherited copper toxicosis has been reported in American Bedlington terrier families. Due to the fact that there is little exchange of breeding stock between the USA and Europe, it remains to be investigated whether in Europe the marker is informative and is linked with the disease. We have therefore examined the diagnostic value of the microsatellite marker in the European Bedlington. In 130 dogs at least one year of age (62 from The Netherlands, 35 from Belgium, and 33 from Germany) histo- or cytochemical staining of copper was done in liver biopsies. Based on liver histo- or cytochemistry, 51 dogs were obligate carriers, and 25 dogs had copper toxicosis. The inferred genotypes of these 76 dogs were compared with the marker genotypes. All dogs with the disease were homozygous for the 167 bp marker allele. All obligate carriers were heterozygotes with the 167 bp and a 163-bp alleles. All phenotypically healthy dogs were either homozygous for the 163 bp allele or heterozygous. Thus, the marker was in complete linkage disequilibrium with the putative copper toxicosis gene with the 167 bp allele in phase with the disease allele. The frequencies of the 167 bp and the 163 bp allele, respectively, were 0.33 and 0.67 in Dutch dogs, 0.31 and 0.69 in German dogs, and 0.57 and 0.43 in Belgian dogs. We have confirmed the utility of this marker for diagnosis of inherited copper toxicosis in European Bedlington terriers.  相似文献   
25.
Summary

The mountains of the Western Highlands of Scotland support a lichen vegetation that is apparently unique in Europe, and probably the world. This lichen vegetation consists mainly of microlichens and is important both intrinsically, with a number of rare and apparently endemic taxa and communities, and as a major contributor to the botanical biodiversity of the ecosystem. By contrast, the lichen vegetation of the Eastern Highlands, which consists mostly of terricolous macrolichens, is best considered a fragmented, species-poor outlier of that present in Scandinavia and is of national interest only.  相似文献   
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