196 research outputs found

    Metasomatism induced by alkaline magma in the upper mantle of northern Victoria Land (Antarctica): an experimental approach

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    Magma generation in the Ross Sea system is related to partial melting of strongly metasomatised mantle sources where amphibole most probably plays a crucial role. In this context, metasomatism induced by a mela-nephelinite melt in lithospheric mantle of the Mt. Melbourne Volcanic Province (northern Victoria Land – NVL, Antarctica) was investigated experimentally studying the effects of melt interaction with lherzolite at 1.5-2.0 GPa and T=975-1300°C, and wehrlite at 1.0 GPa and T=1050-1250°C. The experiments were designed to induce melt infiltration into the ultramafic rocks. The observed modifications in minerals are compared with those found in mantle xenoliths from NVL. The effects of metasomatic modifications are evaluated on the basis of run temperature, distance from the infiltrating melt and on the diffusion rates of chemical components. Both in lherzolite and wehrlite, clinopyroxene exhibits large compositional variations ranging from primary diopside to high Mg-Cr-(Na) augitic and omphacitic clinopyroxenes in lherzolite, and to low Mg and high Ti-Al-Fe-Na augites in wehrlite. Olivine (in wehrlite) and spinel (in lherzolite) also result compositionally modified, the former shows enrichments in Fe, the latter displays a higher Cr/(Cr+Al) ratio. The systematic variations in mineral compositions imply modifications of the chemistry of the infiltrating melt as recorded by the glass veinlets and patches observed in some charges. In experiments involving wehrlite paragenesis, the glass composition approaches that of melt patches associated to both amphibole-free and amphibole-bearing natural samples, and is related to olivine+clinopyroxene crystallisation coupled with primary clinopyroxene dissolution at the contact between the metasomatising melt and the solid matrix. Even if amphibole crystallisation was not attained in the experiments, we were able to explain the occurrence of amphibole in the natural system considering that in this case a hot metasomatising melt infiltrates a cooler matrix

    Continuity and change - The planning and management of long distance walking routes in Scotland

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    In recent years a number of changes have taken place in Scotland in respect of issues of land management, access and the natural environment. These include the creation of Scotland’s first National Parks in 2002 and the introduction of the Land Reform (Scotland) Act 2003, which has enshrined in legislation the principle of responsible access in the countryside. The aim of this study was to consider the implications of these changes for a specific type of recreational land use in Scotland, Long Distance (Walking) Routes (LDRs). Using semi-structured interviews with representatives of a number of agencies and with other individuals closely involved with LDRs, the research considered the extent to which these changes have or may alter the rationale for the provision of LDRs, their funding and their management. The research indicates a need and a willingness to build on existing stakeholder approaches to management with a view to engaging a broader range of communities of interest. The main challenge for those involved with LDRs is how to fund future development of these routes. One aim of a more participatory stakeholder management approach is to help route managers to use public funds to lever funds from other source

    Health and safety issues in the Victorian workplace: an example of mandibular phosphorus necrosis from Gloucester, UK

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    Working conditions in factories during the Industrial Era in Great Britain have been linked to numerous occupational diseases. In this paper, the authors present a case study from Victorian Gloucester, where skeletal remains of a young male recovered from the Southgate Street 3/89 excavation exhibit osteonecrosis on the left mandibular ramus, a condition known as “phossy jaw”. The case is examined in terms of macroscopic characteristics, distribution and severity of lesions and differential diagnosis. The lesions consist of extensive bone necrosis with periosteal reaction and subperiosteal new bone formation that affects the left side of the mandible. Conditions that may have produced similar changes were considered and include various forms of neoplasms, actinomycosis and taphonomic alterations. However, these are rejected as they are not supported by the lesion characteristics. Additional supportive evidence for the case of phosphorus necrosis is offered by the historical context: in the 19th century, Gloucester was one of the main centres for match manufacture and it is well known that individuals who were directly exposed to phosphorus fumes developed a condition known as “phossy jaw”. The potential contribution of the current analysis in our understanding of working conditions in Victorian Gloucester is evaluated

    Practitioner insights as a means of setting a context for conservation

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    A key obstacle to conservation success is the tendency of conservation professionals to tackle each challenge individually rather than collectively and in context. We sought to prioritize barriers to conservation previously described in the conservation literature. We undertook an online survey of 154 practitioners from over 70 countries to ascertain the most important barriers to conservation they faced. We used statistical analyses to identify the key impediments to conservation success and to examine whether these were affected by organizational attributes. Twenty‐one barriers were identified. The importance ascribed to those was influenced by continent of operation and organization size, but not by organization age or autonomy (from larger parent organizations). We found the most important barriers to consider when undertaking conservation action were wider issues (e.g., population growth, consumerism, favoring development, and industrial‐scale activity), operating environment (e.g., lack of political will, ineffective law enforcement, weak governments, corruption, safety and security), community attributes (e.g., dynamics, conflicts, and education levels), and the way conservation is undertaken (overconfidence, lack of funding, and externally set agendas). However, we advise against applying a one‐size‐fits‐all approach. We propose that conservationists account for the complex socioecological systems they operate in if they are to achieve success

    Poulton, Cheshire: The investigation of a rural chapel in an evolving medieval landscape

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    This article presents the results of the radiocarbon dating programme and interpretation of a medieval chapel and graveyard in Poulton, Cheshire. The structure was associated with a lost Cistercian Abbey of 12th-13th-century date, which was relocated to Staffordshire after c. 60 years. Extensive excavation has revealed a minimum of 783 interments, interpreted as the remains of the farming community who worked the land after the monks’ departure. The role of the chapel within the early Cistercian landscape has proved enigmatic, although archaeological investigation has enabled a detailed understanding of the development of this ecclesiastical structure. The radiocarbon dating programme has revealed the chronology of the graveyard. By combining this new evidence with the historical record and archaeological data, an interpretation of the changing role of the chapel within the evolving medieval landscape is presente

    The Institutional Sustainability in Protected Area Tourism-Case Studies of Jiuzhaigou National Scenic Area, China and New Forest National Park, United Kingdom

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    This article considers sustainable tourism development in two protected areas, Jiuzhaigou National Scenic Area in China and the New Forest National Park in the United Kingdom. An inductive approach is used to explore the "fourth component" of sustainable tourism development that is institutional sustainability. Primary data from in-depth interviews, together with a range of secondary data sources, are analyzed to understand the governance and management of each area. These reveal that whilst each area is committed to sustainable development, their approaches differ because of the political, economic, and socio-cultural contexts. The implications for policy and practice are then discussed. © Taylor & Francis Group, LLC

    Expansion of Nature Conservation Areas: Problems with Natura 2000 Implementation in Poland?

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    In spite of widespread support from most member countries’ societies for European Union policy, including support for the sustainable development idea, in many EU countries the levels of acceptance of new environmental protection programmes have been and, in particular in new member states, still are considerably low. The experience of the countries which were the first to implement union directives show that they cannot be effectively applied without widespread public participation. The goal of this study was, using the example of Poland, to assess public acceptance of the expansion of nature conservation in the context of sustainable development principles and to discover whether existing nature governance should be modified when establishing new protected areas. The increase in protected areas in Poland has become a hotbed of numerous conflicts. In spite of the generally favourable attitudes to nature which Polish people generally have, Natura 2000 is perceived as an unnecessary additional conservation tool. Both local authorities and communities residing in the Natura areas think that the programme is a hindrance, rather than a help in the economic development of municipalities or regions, as was initially supposed. This lack of acceptance results from many factors, mainly social, historic and economic. The implications of these findings for current approach to the nature governance in Poland are discussed
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