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1.
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   

2.
Shellfish aquaculture is a growing industry in Scotland, dominated by the production of the mussel Mytilus edulis, the native species. Recently the discovery of Mytilus galloprovincialis and Mytilus trossulus together with M. edulis and all 3 hybrids in cultivation in some Scottish sea lochs led to questions regarding the distribution of mussel species in Scotland. The establishment of an extensive sampling survey, involving the collection of mussels at 34 intertidal sites and 10 marinas around Scotland, motivated the development of a high-throughput method for identification of Mytilus alleles from samples. Three Taqman®-MGB probes and one set of primers were designed, based on the previously described Me 15/16 primers targeting the adhesive protein gene sequence, and samples were screened for the presence of M. edulis, M. galloprovincialis and M. trossulus alleles using real-time PCR. Mytilus edulis alleles were identified in samples from all 44 sites. Mytilus galloprovincialis alleles were found together with M. edulis alleles extensively in northern parts of the west and east coasts. Mytilus trossulus alleles were identified in samples from 6 sites in the west and south-west of Scotland. Because M. trossulus is generally undesirable in cultivation and therefore preventing the geographical spread of this species across Scotland is considered beneficial by the shellfish aquaculture industry, these 6 samples were further analysed for genotype frequencies using conventional PCR. Although distribution of the non-native species M. galloprovincialis and M. trossulus have proven to be more widespread than previously thought, there is no evidence from our study of either M. trossulus or M. galloprovincialis acting as an invasive species in Scotland. The real-time PCR method developed in this study has proven to be a rapid and effective tool for the identification of M. edulis, M. galloprovincialis and M. trossulus alleles from samples and should prove useful in future surveys, ecological or aquaculture management related studies in both unispecific and mixed species areas of these species.  相似文献   

3.
Capsule The population of breeding Hen Harriers in the UK and Isle of Man increased between 1998 and 2004, although country and regional trends differed.

Aims To estimate the size of the UK and Isle of Man Hen Harrier breeding population in 2004, and to compare this with previous estimates made in 1988/89 and 1998.

Methods Surveys were carried out in core and a stratified random sample of 10-km squares throughout the known range, using the same methods as in the 1988/89 and 1998 national surveys.

Results There were an estimated 806 territorial pairs in the UK and Isle of Man in 2004, a significant 41% increase from the 1998 estimate of 570 pairs. Increases were found throughout, with the exception of south and east Scotland and England, where numbers decreased. Scotland held 79% of the UK and Isle of Man breeding population in 2004, and 10% of Scottish pairs were associated with non-moorland habitats, such as mature conifer plantations and scrub/brash.

Conclusions There was a substantial increase in the breeding population in most regions of the UK and Isle of Man between 1998 and 2004, possibly aided by increased use of non-moorland habitats. However, populations declined in upland areas of southern and eastern Scotland and northern England. Continuing illegal persecution arising from perceived conflicts between breeding Hen Harriers and driven grouse shooting may be a major cause of these regional declines.  相似文献   

4.
《Plains anthropologist》2013,58(71):29-44
Abstract

Mandan Tradition ceramics in northern Wyoming and adjacent areas of Montana and South Dakota have been attributed to the Crow Indians. A decade of excavation and collection of this pottery suggests it may have first appeared around the beginning of the 16th Century and lasted well into the 18th Century although these dates are tentative. Several restorable vessels provide a better knowledge of the range and shapes and design elements.  相似文献   

5.
Capsule The third national Merlin survey estimated a UK population of 1162 breeding pairs (95% CI: 891–1462).

Aims To estimate the number of breeding Merlins (with associated 95% confidence intervals) in the UK and the four countries (Scotland, England, Wales and Northern Ireland), and to compare these with the relevant estimates from the 1993–94 Merlin survey. In addition, to calculate estimates of change for several regional populations with complete survey coverage during both national surveys.

Methods A subset of 10-km squares (Raptor Study Group squares and randomly sampled squares) was surveyed across the breeding distribution of Merlins in the UK using standardised methods devised during the 1993–94 national survey.

Results The population estimate for Merlins in the UK was 1162 breeding pairs, and in Britain was 1128 pairs (95% CI: 849–1427), which although 13% lower, was not significantly different from the British estimate of the 1993–94 survey. Scotland held the bulk (733 pairs) of the UK Merlin population, and smaller numbers of 301 pairs, 94 pairs and 32 pairs were estimated for England, Wales and Northern Ireland, respectively. The population estimate for Wales may have been biased upwards by low coverage in the south of the country. Marked declines were noted in several regional Merlin populations, particularly in areas of northern England.

Conclusions The 2008 Merlin survey suggests that the population in Britain has remained relatively stable since 1993–94, but with local declines, particularly in northern England. Currently, little is known about important drivers of regional population change in Merlins, but changes in land-use, prey populations and climate are likely to be important factors.  相似文献   

6.
Capsule Stable isotope composition of feathers grown in Africa indicates that Willow Warblers, Phylloscopus trochilus, breeding in areas of Britain experiencing different population trends may vary in their distribution, timing of moult and/or use of prey resources during the non-breeding season.

Aims To compare stable isotope ratios of feathers of Willow Warblers breeding in parts of Britain with differing rates of population change.

Methods Feathers were collected from three regions with differing recent population trends; northern Scotland (population increased), western Wales (declined slightly) and eastern England (declined rapidly). Collection occurred at ringing sites run by British Trust for Ornithology (BTO) volunteers as part of the Constant Effort Sites (CES) scheme between April and July in 2008 and 2009.

Results Willow Warblers from northern Scotland had significantly higher δ 15N and δ 13C values than those from eastern England, although the regional mean values did not differ greatly. There was no significant difference in δ 15N and δ 13C values between the sexes, but δ 15N values were significantly greater in individuals caught later in the breeding season.

Conclusions During the premigratory moult period in Africa, Willow Warblers from different parts of Britain may vary in their distribution, timing of moult and/or use of prey resources.  相似文献   

7.
Capsule The UK Corncrake population increase has slowed, but has rapidly recovered from a large decline in 2013.

Aims To provide an update on the population size and distribution of breeding Corncrakes in the UK, including the results of the most recent full national survey and annual monitoring of the core population.

Methods A full survey of singing Corncrakes was undertaken in the UK and the Isle of Man in 2009, following the last full censuses in 1978/79, 1988, 1993, 1998 and 2003. Monitoring of singing male Corncrakes within the core range in northern and western Scotland has been undertaken annually since 1993.

Results The 2009 results show that numbers increased substantially since 2003, from 829 to 1166 singing males. Corncrake numbers in the core range have increased in 17 of the 21 years between 1993 and 2014, and peaked at 1274 singing males, in 2014. Numbers of singing males dropped by 24% between 2012 and 2013, probably due to a particularly cold spring in 2013 that inhibited growth of vegetation cover, but numbers recovered markedly in 2014.

Conclusion The recovery of the UK Corncrake population has continued since a low point in 1993. However there are no signs of range expansion into mainland UK, away from the core breeding areas in Scotland. The large decline in the core population between 2012 and 2013 highlights the sensitivity of the population to external factors, although the subsequent increase in 2014 shows a capacity for rapid recovery.  相似文献   

8.
《Journal of bryology》2013,35(1):12-19
Abstract

Scotland’s mountains are home to a rare and unique liverwort community, ‘the oceanic-montane liverwort-rich heath’, but its component species are absent from regions where they could potentially thrive. Many biological characteristics of these species are unknown, making it impossible to explain the reasons for their rarity; however, they have not been observed to produce sporophytes within Britain. We use ex situ cultivation of whole liverworts and fragments, and in situ cultivation of fragments, to assess the growth rate and the potential for vegetative reproduction of several species. Most of the species grew from both fragments and as whole plants, indicating that the rarity of the liverwort heath is not due to poor powers of regeneration. We propose that growth rate and the potential to regenerate from fragments are important factors structuring the liverwort heath community, at least locally. Furthermore, this study demonstrates that there is potential for ex situ conservation of rare liverwort species, in situ enhancement of existing populations, and creation of new ones.  相似文献   

9.
Summary

A new species of the genus Closterium possessing true girdle bands, a striated wall and distinctive apical features has been found in a disused water-filled quarry on A'Mhoine, northern Sutherland, Scotland.  相似文献   

10.
Summary

Scottish habitats are here reviewed in a European context. Examples are selected in order to identify those recognisable as distinctively Scottish as well as others related to Scandinavian or European counterparts. The paper begins with a resumé of the main environmental influences in Scotland, then describes examples of habitats almost unique to, or best represented in Scotland. This is followed by reference to some distinctively western versions of more widely distributed habitats, and others corresponding to related types elsewhere. The bearing of this on site selection for nature conservation is discussed. Hitherto, in the UK selection for National Nature Reserves and Sites of Special Scientific Interest has been based largely on the criteria listed in A Nature Conservation Review (Ratcliffe, 1977). It is important, however, also to review Scottish habitats in a European context, as attempted in this paper. In making proposals (now approaching completion) for Special Areas of Conservation, to be recommended by the UK Government for adoption by the European Commission, it is now our duty to include not only habitats for which we have special responsibility because they are unique to or best represented in Scotland, or have distinctively western features, but also sufficient examples of all the main European types occurring in our country.

Nomenclature of British flowering plants and ferns follows Stace (1991).  相似文献   

11.
《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   

12.
The status of the four currently recognised species in the Littorina saxatilis species-complex, i.e. Littorina nigrolineata Gray, L. arcana Hannaford Ellis, L. saxatilis (Olivi) and L. neglecta Bean is reviewed briefly, with notes on their characteristic features and location on the shore. Since the taxonomy of these rough periwinkles has only become stable relatively recently much of the previously published information on distribution is of little or no use. In this paper their distribution around the coastline of England and Wales (with some notes on Scotland) is described and discussed. L. saxatilis is found in a wide range of habitats from exposed peninsulas to estuaries on all shores where there is a suitable rocky or stony substrate; also in salt marsh pools. L. arcana has a more restricted distribution and is notably absent along much of the south English coast, central Cardigan Bay and possibly northern Scotland; it is not found in estuaries. L. nigrolineata has an even more restricted distribution, although it occurs both on exposed coasts and in estuaries; it has only been found by us in one locality on the east coast. L. neglecta is probably fairly widely distributed but we have few details so far. The implications of the different patterns of distribution are discussed.  相似文献   

13.
The archaeological site of Lavazzé at 2108 m a.s.l., and the summer farming site of Borghetto Sotto at 1897 m a.s.l., have been studied using pollen analysis. The pollen diagrams reflect human disturbance from the Bronze and Neolithic ages respectively. The name Lavazzé is also used as a local name for Rumex alpinus. At both sites, significant values of R. alpinus, up to about 10% of total terrestrial pollen, have been recorded, from about 2400 b.p. (ca 360 cal b.c.) onwards, although Lavazzé is above the present-day known local limit for R. alpinus. Written sources document local growth and cultivation of the species at 1300 m. It was used for various purposes in the past, and the high values are interpreted as reflecting former intensive local growth. Local cultivation at higher altitudes should not be excluded. Use of R. alpinus is known as far north as Scotland and Finland, and the species ought to be regarded as an apophyte and/or a naturalised crop.  相似文献   

14.
15.
ObjectiveTo investigate international variations in smoking associated with educational level.DesignInternational comparison of national health, or similar, surveys.SubjectsMen and women aged 20 to 44 years and 45 to 74 years.Setting12 European countries, around 1990.ResultsIn the 45 to 74 year age group, higher rates of current and ever smoking among lower educated subjects were found in some countries only. Among women this was found in Great Britain, Norway, and Sweden, whereas an opposite pattern, with higher educated women smoking more, was found in southern Europe. Among men a similar north-south pattern was found but it was less noticeable than among women. In the 20 to 44 year age group, educational differences in smoking were generally greater than in the older age group, and smoking rates were higher among lower educated people in most countries. Among younger women, a similar north-south pattern was found as among older women. Among younger men, large educational differences in smoking were found for northern European as well as for southern European countries, except for Portugal.ConclusionsThese international variations in social gradients in smoking, which are likely to be related to differences between countries in their stage of the smoking epidemic, may have contributed to the socioeconomic differences in mortality from ischaemic heart disease being greater in northern European countries. The observed age patterns suggest that socioeconomic differences in diseases related to smoking will increase in the coming decades in many European countries.  相似文献   

16.
BackgroundRurald wellers with colorectal cancer have poorer outcomes than their urban counterparts. The reasons why are not known but are likely to be complex and be determined by an interplay between geography and health service organization. By comparing the associations related to travel-time to primary and secondary healthcare facilities in two neighbouring countries, Denmark and Scotland, we aimed to shed light on potential mechanisms.MethodsAnalysis was based on two comprehensive cohorts of patients diagnosed with colorectal cancer in Denmark (2010−16) and Scotland (2007−14). Associations between travel-time and cancer pathway intervals, tumour stage at diagnosis and one-year mortality were analysed using generalised linear models. Travel-time was modelled using restricted cubic splines for each country and combined. Adjustments were made for key confounders.ResultsTravel-time to key healthcare facilities influenced the diagnostic experience and outcomes of CRC patients from Scotland and Denmark to some extent differently. The longest travel-times to a specialised hospital appeared to afford the most rapid secondary care interval, whereas moderate travel-times to hospital (about 20−60 min) appeared to impact on later stage and greater one-year mortality in Scotland, but not in Denmark. A U-shaped association was seen between travel-time to the GP and one year-mortality.ConclusionsThis is the first international data-linkage study to explore how different national geographies and health service structures may determine cancer outcomes. Future research should compare more countries and more cancer sites and evaluate the impact and implications of differences in national health service organisation.  相似文献   

17.
AimsAlzheimer's disease (AD) is the leading cause of dementia. The increased cdk5 expression and enhanced phosphorylation of tau and NFs have been seen in AD patients. Our study aimed at investigating the effects of increased cdk5 activity on axonal transport of neurofilaments (NFs).Main methodsIn this study, we used a molecular engineering approach to overexpress cdk5/p25 in neuroblastoma N2a cells and investigated the effects on axonal transport with live cell imaging techniques.Key findingsIn stably transfected cells, there was a 2.5-fold increase in cdk5 activity compared to non-transfected cells, which in turn led to a dramatic increase in phosphorylation of NFs and tau at several phosphorylation sites. Using time-lapse imaging technology, the transport of NFs was captured in the cells overexpressing cdk5/p25, which were also transiently transfected with fluorescence protein linked to the N-terminus of NF-M (EGFP-NFM). The cdk5/p25 cells displayed significantly slower rates of axonal transport of NFs, with accumulation of immobile NF clusters observed in the cell body. Roscovitine, an inhibitor of cdk5, significantly reversed this defect in axonal transport.SignificanceThese results suggest that increased cdk5 activity found in AD subjects may be crucially related to the pathogenesis of AD via an underlying mechanism by which it promotes accumulation of excessively phosphorylated cytoskeletal NF proteins, leading to the enduring impairment of axonal transport of NFs.  相似文献   

18.
BackgroundHumanin (HN) is an endogenous peptide factor and known as a member of mitochondrial-derived peptides. We first found the gene encoding this novel 24-residue peptide in a brain of an Alzheimer's disease (AD) patient as an antagonizing factor against neuronal cell death induced by AD-associated insults.Scope of reviewThis review presents an overview of HN actions in AD-related conditions among its wide range of action spectrum as well as a brief history of the discovery.Major conclusionsHN exhibits multiple intracellular and extracellular anti-cell death actions and antagonizes various AD-associated pathomechanisms including amyloid plaque accumulation.General significanceThis review concisely reflects accumulated knowledge on HN since the discovery focusing on its functions related to AD pathogenesis and provides a perspective to its potential contribution in AD treatments.  相似文献   

19.
《Free radical research》2013,47(8):569-576
Abstract

A number of evidences indicates oxidative stress as a relevant pathogenic factor in Alzheimer's disease (AD) and mild cognitive impairment (MCI). Considering its recognized major genetic risk factors in AD, apolipoprotein (APO E) has been investigated in several experimental settings regarding its role in the process of reactive oxygen species (ROS) generation. The aim of this work has been to evaluate possible relationships between APO E genotype and plasma levels of selected oxidative stress markers in both AD and MCI patients.

APO E genotypes were determined using restriction enzyme analysis. Plasma levels of oxidative markers, advanced oxidation protein products, iron-reducing ability of plasma and, in MCI, activity of superoxide dismutases were evaluated using spectrophotometric analysis.

We found, compared to controls, increased levels of oxidized proteins and decreased values of plasma-reducing capacity in both AD patients (p < 0.0001) and MCI patients (p < 0.001); the difference between AD and MCI patients was significant only for plasma-reducing capacity (p < 0.0001), the former showing the lowest values. Superoxide dismutase activity was reduced, although not at statistical level, in MCI compared with that in controls. E4 allele was statistically associated (p < 0.05) with AD patients. When comparing different APO E genotype subgroups, no difference was present, as far as advanced oxidation protein products and iron-reducing ability of plasma levels were concerned, between E4 and non-E4 carriers, in both AD and MCI; on the contrary, E4 carriers MCI patients showed significantly decreased (p < 0.05) superoxide dismutase activity with respect to non-E4 carriers.

This study, in confirming the occurrence of oxidative stress in AD and MCI patients, shows how it can be related, at least for superoxide dismutase activity in MCI, to APO E4 allele risk factor.  相似文献   

20.
Capsule Population trends for Chaffinch on farmland are unlikely to be explained by their preference for non-crop habitats alone.

Aims To investigate the importance of non-cropped habitats for Chaffinch territory distribution, breeding success and foraging habitat selection in Scottish farmland.

Methods Territory distribution, nesting success and foraging behaviour of adults feeding chicks at the nest were recorded and related to habitat composition on two Scottish lowland farms.

Results Higher Chaffinch territory densities were associated with the presence of hedgerows, trees and grass leys, whereas lower densities were found adjacent to winter Barley. Nests were predominantly located in conifer trees and hedgerows. Trees were selected preferentially for foraging. Poor breeding success was detected in nests associated with cereal crops and wider field margins. Farmland in Scotland supported much lower territory densities than in England.

Conclusion Chaffinches rely predominantly on non-cropped habitats for territory establishment, nesting and foraging habitats. Differences in habitat composition between England and Scotland may explain differences in territory densities. However, the Chaffinch's preference for non-crop habitats is unlikely to explain its population trends alone. Immigration from other habitats and/or a decrease in inter-specific competition for resources may also have contributed to the increase in the national farmland Chaffinch population.  相似文献   

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