246 resultados para British


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Accurate knowledge of species’ habitat associations is important for conservation planning and policy. Assessing habitat associations is a vital precursor to selecting appropriate indicator species for prioritising sites for conservation or assessing trends in habitat quality. However, much existing knowledge is based on qualitative expert opinion or local scale studies, and may not remain accurate across different spatial scales or geographic locations. Data from biological recording schemes have the potential to provide objective measures of habitat association, with the ability to account for spatial variation. We used data on 50 British butterfly species as a test case to investigate the correspondence of data-derived measures of habitat association with expert opinion, from two different butterfly recording schemes. One scheme collected large quantities of occurrence data (c. 3 million records) and the other, lower quantities of standardised monitoring data (c. 1400 sites). We used general linear mixed effects models to derive scores of association with broad-leaf woodland for both datasets and compared them with scores canvassed from experts. Scores derived from occurrence and abundance data both showed strongly positive correlations with expert opinion. However, only for occurrence data did these fell within the range of correlations between experts. Data-derived scores showed regional spatial variation in the strength of butterfly associations with broad-leaf woodland, with a significant latitudinal trend in 26% of species. Sub-sampling of the data suggested a mean sample size of 5000 occurrence records per species to gain an accurate estimation of habitat association, although habitat specialists are likely to be readily detected using several hundred records. Occurrence data from recording schemes can thus provide easily obtained, objective, quantitative measures of habitat association.

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1. Species’ distributions are likely to be affected by a combination of environmental drivers. We used a data set of 11 million species occurrence records over the period 1970–2010 to assess changes in the frequency of occurrence of 673 macro-moth species in Great Britain. Groups of species with different predicted sensitivities showed divergent trends, which we interpret in the context of land-use and climatic changes. 2. A diversity of responses was revealed: 260 moth species declined significantly, whereas 160 increased significantly. Overall, frequencies of occurrence declined, mirroring trends in less species-rich, yet more intensively studied taxa. 3. Geographically widespread species, which were predicted to be more sensitive to land use than to climate change, declined significantly in southern Britain, where the cover of urban and arable land has increased. 4. Moths associated with low nitrogen and open environments (based on their larval host plant characteristics) declined most strongly, which is also consistent with a land-use change explanation. 5. Some moths that reach their northern (leading edge) range limit in southern Britain increased, whereas species restricted to northern Britain (trailing edge) declined significantly, consistent with a climate change explanation. 6. Not all species of a given type behaved similarly, suggesting that complex interactions between species’ attributes and different combinations of environmental drivers determine frequency of occurrence changes. 7. Synthesis and applications. Our findings are consistent with large-scale responses to climatic and land-use changes, with some species increasing and others decreasing. We suggest that land-use change (e.g. habitat loss, nitrogen deposition) and climate change are both major drivers of moth biodiversity change, acting independently and in combination. Importantly, the diverse responses revealed in this species-rich taxon show that multifaceted conservation strategies are needed to minimize negative biodiversity impacts of multiple environmental changes. We suggest that habitat protection, management and ecological restoration can mitigate combined impacts of land-use change and climate change by providing environments that are suitable for existing populations and also enable species to shift their ranges.

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‘White Youth’ recovers and explains the relationship between far-right organisations and British youth culture in the period between 1977 and 1987. In particular, it concentrates on the cultural spaces opened up by punk and the attempts made by the National Front and British Movement to claim them as conduits for racist and/or ultra-nationalist politics. The article is built on an empirical basis, using archival material and a historical methodology chosen to develop a history ‘from below’ that takes due consideration of the socio-economic and political forces that inform its wider context. Its focus is designed to map shifting cultural and political influences across the far right, assessing the extent to which extremist organisations proved able to adopt or utilise youth cultural practice as a means of recruitment and communication. Today the British far right is in political and organisational disarray. Nonetheless, residues tied to the cultural initiatives devised in the 1970s–80s remain, be they stylistic, nostalgic or points of connection forged to connect a transnational music scene.

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Excavation west of Wivelsfield, East Sussex, revealed part of an early Romano-British settlement. One of the round-houses may have had a non-domestic, possibly ritual, function. The settlement appears to have been subsequently incorporated within a rectilinear arrangement of field/enclosure ditches. Along the edge of one of these ditches were built a series of features interpreted as ovens, of varying form and likely use, from which charred waste from cereal processing and charcoal from coppiced woodland were recovered.

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Research on international differences in retail productivity has highlighted formidable environmental barriers to the ‘industrialisation’ of mass retailing as a driver of declining British interwar productivity growth in this sector (and in services more generally). We examine evidence for such barriers, using a case study of a firm that built its interwar expansion strategy on ‘American’ retail methods – Marks & Spencer (M&S). We find that, rather than facing barriers to the adoption of American mass retail practices, M&S reaped major productivity gains from this process. This adds further evidence to an emerging literature rejecting the barriers to industrialisation thesis for retailing.