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1.
In the Scottish Highlands, Scots pine is at the north-western extreme of its wide natural distribution. Here, the remaining native populations are patchily distributed in highly variable environments, from the more continental, drier eastern Highlands to the milder, wetter Atlantic Ocean coast. As these pinewoods are the remnants of a naturally established forest, they form a valuable system for analysis of genetic and adaptive variation in heterogeneous environments. Using samples from across the Scottish population, we analysed data from nuclear and mitochondrial genes to assess patterns of within and between population genetic variation. Within population diversity levels were high, and significant genetic differentiation among pairs of Scottish populations at relatively small spatial scales was present at several nuclear loci. At these loci, no differentiation had been found among continental populations, even those separated by large geographic distances. Overall, no clear clustering of Scottish samples was found in population structure analysis suggesting that geographically distant populations with high intra-population nucleotide diversity are not strongly isolated or diverged from each other. Scottish populations lacked a mitotype that is widespread in eastern and north-eastern Europe, indicating that pines from that area may not have participated in the most recent colonisation of the British Isles.  相似文献   

2.
Market-based economic incentives are increasingly perceived as a cost-effective approach to biodiversity conservation but empirical evidence to substantiate this claim is lacking. Using both qualitative and quantitative data analysis this paper investigates the potential role of market incentives to increase venison production as a mechanism to resolve conflicts over wild red deer management in the Scottish Highlands. Our analysis suggests the approach is unlikely to be effective because investments in venison production would bring conflict with more important non-pecuniary objectives of landownership such as ‘sporting quality’ and ‘exclusivity’. At a broader level we urge caution when considering the deployment of economic instruments to resolve contemporary conservation conflicts where profit maximisation is not the dominant objective and/or where the target group is extremely wealthy.  相似文献   

3.
A study was carried out, primarily in northern Scotland, to relate bill and wing measurements to diagnostic calls of crossbill species, and thereby use the calls to describe the distributions and habitats of the different species. Bill depth and wing length measurements from museum specimens and live‐trapped birds were used to describe the size categories. Almost all measurements of crossbills from England were similar to measurements of Common Crossbills from Fennoscandia. Museum specimens showed that crossbills in northern Scotland between 1822 and 1990 were a combination of Common Crossbills, birds which were intermediate between Common and Parrot Crossbills (Scottish Crossbills), and perhaps a few Parrot Crossbills. However, catches of crossbills between 1995 and 2000 showed that Parrot Crossbills (based on bill and wing measurements) were present at some sites in the Highlands. Recordings of flight calls and excitement calls of birds of known bill sizes allowed a classification of crossbills according to call types. Four different flight calls (referred to here as types 1–4) and five excitement calls (types A–E) were recognized. A sample of small‐billed birds, thereby identified as Common Crossbills, indicated that there were three groups of Common Crossbills: those giving type 1 flight calls and type A excitement calls (1A), type 2 flight calls and type B excitement calls (2B), and type 4 flight calls and type E excitement calls (4E). Large‐billed birds identified as Parrot Crossbills gave mainly type 2 flight calls and type D excitement calls. Birds with intermediate bill depths (Scottish Crossbills) gave type 3 flight calls and type C excitement calls. Distributions based on calls showed that 1A Common Crossbills were widespread in Scotland but the other types of Common Crossbill were rare. Parrot Crossbills were found in a few localities in the Highlands, and Scottish Crossbills (defined as those giving type 3 flight calls and type C excitement calls) were restricted to the northern and eastern Highlands. Scottish Crossbills and 1A Common Crossbills had overlapping distributions, and overlapped greatly in the types of forests they used between January and March when the Scots Pine cones were still closed. However, Scottish Crossbills were more frequently associated with stands containing Scots Pine compared with Common Crossbills.  相似文献   

4.
《Journal of bryology》2013,35(4):253-257
Abstract

The liverwort Athalamia hyalina (Sommerf.) S.Hatt. and the family Cleveaceae are reported as new to the British Isles from the eastern Scottish Highlands. The Scottish plants are described and illustrated and the significance of the discovery is assessed. In Scotland, Athalamia hyalina occurs on thin soil on eroding limestone ledges in a montane habitat with a continental climate. It is in active growth in the winter months, producing spores in spring. Its range is restricted but it occurs within a protected area and is not threatened at present. The species is widespread in the northern hemisphere.  相似文献   

5.
Abstract:The lichen vegetation associated with areas of late snow-lie in the Scottish Highlands is described and three lichen-dominated communities recognized; from the tops of large boulders, from small pebbles, and from damp soil. The first of these is exclusive to this habitat throughout the Highlands, whereas the other two are restricted to areas of late snow-lie in the Eastern Highlands but are of more widespread occurrence further west. The community from damp soil has affinities with the Solorinion croceae Klement, which occupies a similar ecological niche in Central Europe, but the two other communities are apparently undescribed. The importance of the eu-oceanic climate of the Western Highlands in determining the distribution of these communities is emphasized. The new combination Micarea cinerea f. tenuispora (D. Hawksw. & Poelt) Fryday is made for the anamorph of M. cinerea (Schaer.) Hedl.  相似文献   

6.
The population of the Scottish Highlands and Islands had been in a steady decline because of a lack in employment opportunities. Under strong encouragement by the Highlands and Islands Development Board, salmon farming has been a significant factor in reversing this decline. In 1988, aquaculture development in Scotland exceeded 20,000 tonnes of salmon, and provided about 1,600 jobs in fish farming, 120 jobs in feed production, and another 1,800 jobs in processing; it is estimated that over 5,000 people are employed in activities serving aquaculture. The spin-off effects of this development are analyzed in detail. Aquaculture production is compared to the “hands on” value of other industries in the Highlands and Islands of Scotland; worth over £ 80,000,000 at the farm gate, salmon farming ranks alongside beef production and white fish in economic value. A salmon production of 60,000 tonnes is predicted for 1990. Taking the expansion of the salmon industry and other aquaculture activities into account, the calculated impact zone covers about 480 ha only and will occupy only about 0.01 % of national scenic areas. Future prospects in the industry as well as user-conflicts are discussed.  相似文献   

7.
The Highlands of Papua New Guinea have usually been regarded as relatively homogeneous, socially, culturally, and ecologically. In this article I begin with the view that the ethnography of the Eastern and Western Highlands shows great diversity. I argue that this diversity is also evident in the prehistory of the Highlands and that the Eastern and Western Highlands have followed markedly different paths in the development of agriculture and pig husbandry and in their rates of change and transformation. Intensive agriculture and linked pig exchange are very old in the Western Highlands, nascent in the Eastern Highlands. This difference is clear in the ethnographic present, but I argue that it is upon the very different prehistories of the Eastern and Western Highlands that a synchronic comparison of Highlands societies should be mounted.  相似文献   

8.
Data are presented to show how the number and growth of juvenile salmon in streams in the Scottish Highlands are influenced by various physical (temperature, water chemistry, depth and velocity, type of substratum) and biotic (food resources, competition, recruitment) factors.  相似文献   

9.
Abstract: A general account of the lichens of high-level acid habitats in the Lake District is provided. This is followed by detailed studies of base-rich sites in the Helvellyn range, acid outcrops in Langdale, and three upland tarns, one of which is of outstanding importance. The lichen vegetation is richer than in Snowdonia or the Northern Pennines, but its diversity is considerably less than that of certain individual mountains in the Scottish Highlands. The montane element is interpreted as representing the last remnants of communities that have declined gradually through the Postglacial Period. Many species are extremely rare. Current restraints on the alpine lichen flora include the climate, the predominance of wet, acid rock and heavy sheep grazing. Rhizocarpon simillimum is reported as new to the British lichen flora.  相似文献   

10.
Abstract:The results of an investigation into the lichen vegetation associated with vascular plant communities in the Scottish Highlands are presented. Most lichen species rarely occur in homogeneous stands of vascular plant vegetation, either occurring around the edges of recognized National Vegetation Classification (NVC) communities or in small-scale mosaics with them. However, some lichen species have a high fidelity to the more open NVC communities. The problems associated with applying NVC survey techniques to lichen assemblages are described and discussed.  相似文献   

11.
Western ideologies of imperialism conceptualise time as heterogeneous in that they assume that colonised lands are outside of historical time. In this respect, the discursive construction of an empty frontier has been crucial to colonial dispossession. Yet colonial discourses become dominant through their circulation, and so the savage spaces they imagine take on a life of their own when they are revoiced. Papuan Times, a newspaper published by graduates of an industrial mission school at Kwato Island in the colonial Territory of Papua and New Guinea after the Second World War, produces subaltern agency in its reports on the pacification of the Highlands. While its news articles reproduce the heterogeneous chronotope of colonial discourse, articles describing the missionary work of former Kwato students in the Highlands reimagine the Highlands frontier as a horizon of social transformation. The Papuan Times strategy reflects the fact that a community's pursuit of the good exists in relation to others which constrain it, and, more generally, that an anthropology of the good is also an anthropology which recognises the fraught coexistence of a plurality of values.  相似文献   

12.
Escherichia coli was recovered from selected tissues of 43 out of a total of 46 finches found dead in the Scottish Highlands during April–May of 1994 and 1995. The isolates did not ferment sorbitol, rhamnose, sucrose or melibiose; they belonged to serogroup O86:K61, produced cytolethal distending toxin (CLDT) and possessed the eae gene sequence. The consistent recovery of organisms producing CLDT and possessing the eae gene suggests that these organisms may have played a significant role in the finch mortalities.  相似文献   

13.
As with other many game species in Europe, introductions of non-native stock to supplement Scottish red deer populations in an attempt to improve hunting trophy are well reported. These introductions included wapiti (Cervus elaphus canadensis or Cervus canadensis), a species two to three times heavier than the Scottish red deer. However, the effect of these past introductions of wapiti into Scottish red deer populations has not yet been assessed. In this study we sequenced a Y-chromosome marker (Zfy) from 104 collected in three neighbouring estates in the Scottish Highlands including one of the areas with the highest number of wapitis introduced in Scotland, and 45 red deer from an English deer park where introduction of wapiti and subsequent crosses with red deer were a common practice. Analyses revealed that all individuals presented red deer Y-chromosome sequences therefore suggesting a low impact of past introductions of wapiti in the populations under study. Sequencing and phylogenetic analyses of Zfy sequences for four additional deer species revealed that phylogenetic relationships were in agreement with previous mtDNA phylogenetic studies, and demonstrated the potential use of this marker to determine the direction of hybridization in F1 red-sika hybrids.  相似文献   

14.
In the past decade, the hijab has increasingly come to be regarded in the West as an unambiguous symbol of female oppression. Such an orientalist framework rests upon a feminist rhetoric using gender equality as a vehicle for the racialization of Muslims. Correlatively, from the 1970s onwards, conservative Islamist movements have converted the hijab into a natural(ized) symbol of cultural resistance to Western imperialism. In this context, what room is left to Muslim women's agency in the production of the social meanings embedded in veil wearing? I explore this issue by presenting the findings of an interview-based research with veiled and non-veiled high school Muslim female teens in Montreal (Quebec). I show that, although these teenagers have much leeway to bypass and subvert the dominant framings of veil wearing, one should not overestimate their capacity to disrupt the dominant gendered religious framework through which this practice is socially construed.  相似文献   

15.
  • 1 The severe and early destruction and fragmentation of woodland habitats due to human activities is thought to have been a leading factor in the extirpation from Britain of several large, forest‐dependent mammal species, such as the Eurasian lynx Lynx lynx. However, during the 20th century, Scotland in particular has experienced rapid, large‐scale reafforestation. In order to assess if this reafforestation has been sufficient to permit the potential restoration of extirpated forest mammal species with large spatial requirements, a Geographical Information System (GIS) analysis of potential habitat of one species, the Eurasian lynx, was performed for the Scottish mainland.
  • 2 A rule‐based analysis, incorporating data and expert opinion from Switzerland, an environmentally similar area where lynx now occur, was used to identify patches of suitable lynx habitat in Scotland. A connectivity analysis was used to investigate whether and how these patches are connected to form larger interconnected networks of potential lynx habitat that would allow lynx to sufficiently interact with one another to form a single interbreeding population.
  • 3 Scotland has over 20 000 km2 of suitable lynx habitat split into two main networks of interconnected patches: the Highlands (c. 15 000 km2) and the Southern Uplands (c. 5000 km2). A further 800 km2 of potential habitat, contiguous with the Southern Uplands lynx habitat network, lies across the border in England. Although connectivity between the Highlands and Southern Uplands networks is currently weak, the implementation of measures to mitigate the barrier effects of busy roads in central Scotland could facilitate the movement of lynx between the two areas.
  • 4 Based on the availability of prey resources, Scotland could support around 400 adult and subadult lynx in the Highlands and around 50 in the Southern Uplands. A Scottish population of this size would be the fourth largest lynx population in Europe considering current population estimates.
  相似文献   

16.
D. Welch 《Plant Ecology》1967,14(5-6):229-240
Summary Plant communities containing Juncus squarrosus were analysed in a 100 km2 area at the head of Teesdale in the north Pennines. The method of successive approximation was applied, using quadrats of 1/4m2. Five noda were recognised, and their relation to noda previously described from the Scottish Highlands is discussed.The species-rich Juncus-Nardus nodum on irrigated gley soils, and the Juncus-Festuca rubra-Mnium punctatum nodum on flushed peat, contain many hydrophilic species and together constitute an association called species-rich Juncetum squarrosi sub-alpinum. The species-poor Juncus-Nardus nodum occurs on gley soils poorer in bases, and is probably a facies of species-poor Nardetum sub-alpinum. The remaining two noda, the Juncus-Vaccinium myrtillus and the Juncus-Carex nigra-Polytrichum commune, are found on acid, humus-rich soils, being differentiated by freedom of drainage. They contain little Nardus, but constitute an association called species-poor Juncetum squarrosi sub-alpinum. This occupies a considerable area in upper Teesdale, but differs from similar communities described in the Carneddau of north Wales and in the Scottish Highlands in that Agrostis spp. and Anthoxanthum odoratum are scarce. This is perhaps due to long-continued grazing by sheep.  相似文献   

17.
Reintroductions are important tools for the conservation of individual species, but recently more attention has been paid to the restoration of ecosystem function, and to the importance of carrying out a full risk assessment prior to any reintroduction programme. In much of the Highlands of Scotland, wolves (Canis lupus) were eradicated by 1769, but there are currently proposals for them to be reintroduced. Their main wild prey if reintroduced would be red deer (Cervus elaphus). Red deer are themselves a contentious component of the Scottish landscape. They support a trophy hunting industry but are thought to be close to carrying capacity, and are believed to have a considerable economic and ecological impact. High deer densities hamper attempts to reforest, reduce bird densities and compete with livestock for grazing. Here, we examine the probable consequences for the red deer population of reintroducing wolves into the Scottish Highlands using a structured Markov predator-prey model. Our simulations suggest that reintroducing wolves is likely to generate conservation benefits by lowering deer densities. It would also free deer estates from the financial burden of costly hind culls, which are required in order to achieve the Deer Commission for Scotland's target deer densities. However, a reintroduced wolf population would also carry costs, particularly through increased livestock mortality. We investigated perceptions of the costs and benefits of wolf reintroductions among rural and urban communities in Scotland and found that the public are generally positive to the idea. Farmers hold more negative attitudes, but far less negative than the organizations that represent them.  相似文献   

18.
Capsule Low Black Grouse survival rate in northern England during a severe winter with prolonged snow was attributed to limited availability and proximity of woodland.

Aims To compare the impact of the severe winter weather on Black Grouse in an open treeless landscape in northern England with more wooded landscapes in Scotland.

Methods We assessed the impact of severe winter conditions in relation to previous milder winters at a sample of leks counted annually in northern England and the Scottish Highlands between 2001 and 2012. In addition, following the severe winter in 2009/10 Black Grouse were surveyed at all leks in 2010 where they were surveyed the previous year. We assessed woodland habitat extent within 1 km of leks and related this to indices of Black Grouse over-winter survival.

Results Black Grouse in northern England were severely affected by the severe winter of 2009/10, declining by 38% in comparison to a 23% increase in the Scottish Highlands. Leks in northern England were at higher altitudes and had less tree cover than those in Scotland.

Conclusion The lack of woodland cover around leks in northern England implies that availability of above snow forage, shelter and cover from predators was too low for Black Grouse to survive during prolonged deep snow. Measures are required to provide emergency food sources in periods of prolonged snow, such as the provision of supplementary food at leks, the cultivation of seed-rich arable crops, and the establishment of pockets of woodland.  相似文献   

19.
Charcoal assemblages from five Terminal Pleistocene sites in the Central Negev Highlands, Israel, have been analyzed. Eleven taxa have been identified, two of which, juniper andPaliurus, no longer grow in this district, and one,Pinus (of which only a single occurrence was encountered), is considered intrusive, and the rest are taxa which still characterize the region today. Among these latter,Pistacia atlantica (which is the dominant tree in this area today) was the most common. Association of juniper andPaliurus is found today only in the northern Near East. It can not be ascertained that such an association characterized the Central Negev Highlands throughout the entire period spanned by the charcoal assemblages, since it is possible thatPistacia atlantica may have become temporarily extinct. In any case the former occurrence of juniper and particularlyPaliurus in the Central Negev Highlands clearly point to higher humidity in this region during the final stages of the Pleistocene. This conclusion is corroborated by a variety of proxy climatic indicators throughout the southern Levant.  相似文献   

20.
All known rivers in Scotland with recent records of freshwater pearl mussels Margaritifera margaritifera were surveyed in 2013–2015 using a standard methodology. Freshwater pearl mussel populations were classed as: (i) apparently extinct in 11 rivers, (ii) not successfully recruiting in 44 rivers, and (iii) evidence of recent successful recruitment in 71 rivers. On a regional basis, a high proportion of extant populations were located in North and West Scotland. In all regions extant populations were characterised by low pearl mussel densities, with 97 of 115 extant Scottish populations defined as ‘rare’ (0.1–0.9 mussels per 1 m 2) or ‘scarce’ (1.0–9.9 mussels per 1 m 2). Only 18 Scottish rivers now hold pearl mussel populations in densities that are considered to be ‘common’ (10–19.9 mussels per 1 m 2) or ‘abundant’ (>20 mussels per 1 m 2). Based on survey evidence, the number of apparently extinct pearl mussel populations in Scottish rivers is now 73. The decline is particularly pronounced in the West Highlands and Western Isles strongholds. The key threats are: (i) pearl fishing, (ii) low host fish densities, (iii) pollution/water quality, (iv) climate change and habitat loss, (v) hydrological management/river engineering and (vi) ‘other factors’, such as non-native invasive species. Over the last 100 years this endangered species has been lost from much of its former Holarctic range. Scotland’s extant M. margaritifera populations continue to be of international importance, but their continued decline since the first national survey in 1998 is of great concern.  相似文献   

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