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171.
Clearances, interpreted from pollen records during the Mesolithic and Neolithic of Europe, are generally ascribed to purposive deforestation which is compatible with the transition model, whereby early Neolithic economic strategies are a development of late Mesolithic intensification of wild plant food husbandry. This paper considers the role of natural processes in creating clearings and the role of inadvertent impact of human activity on forest processes, including woodland regeneration. The role of climate, wind-throw and lightning strikes in creating clearings and forest instability is emphasised and the evidence discussed from sites which may be interpreted as resulting from opportunistic human use of natural clearings. Unfortunately, regional pollen diagrams lack sufficient spatial resolution to detect the size of isolated clearings or establish the spatial variation in forest composition that was intimately related both to forest ecology and the effects of subtle human impacts. This may be the major reason for an apparent contradiction between pollen evidence of Neolithic impact and the archaeological record. Moreover, early Neolithic agricultural activity may have been concentrated in valley bottoms, which is undetectable in regional pollen diagrams. Alternative models need to be considered, which include culturally specific exploitation of the local environment, along with the inadvertent ecological repercussions of pre-agricultural and early-agricultural human activities in naturally dynamic woodlands.  相似文献   
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Community-based development strategies are gaining in credibility and acceptance in development circles internationally and notably in post-apartheid South Africa. In parallel, the concept of social capital and the role of supportive nongovernmental organizations are receiving attention as key catalytic elements in encouraging and assisting community-based initiatives. In this paper, a well-documented initiative, the Hertzog Agricultural Co-operative in Eastern Cape province, is re-examined after the passage of several years to assess the impact of social capital and the involvement of a particular non-governmental organization in ensuring the sustainability and economic survival of the project. While both elements have proved critical to the project's life-cycle, particularly in recent years, concerns over possible dependency and project sustainability exist.  相似文献   
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Under the influence of the discourses and practices of global neoliberal urbanism, municipal administrations worldwide aspire to make their cities world class spaces, where informality is an anachronism and poverty can be made history. In this essay, drawing on fieldwork conducted in Jakarta, Indonesia, San Francisco (California), and Seattle (Washington), we address the question of how a geographic relational poverty approach can help us understand, or at least expand ways of thinking about these processes by attending to urban informality and the politics of poverty. Informality, a pervasive feature of the global South and North, functions as a survival strategy whereby the monetarily poor can compensate for their lack of income through commoning. Market-driven, state underwritten urban development initiatives for housing those with wealth is limiting the conditions of possibility for the monetarily poor, and informality. This is compounded by emergent political discourses rendering informality as inappropriate, and the monetarily poor as undeserving of a right to the city. Yet long-standing more-than-capitalist and communal informal practices pursued by the urban poor remain effective and necessary survival strategies, supporting residents whose presence is necessary to the city and whose practices challenge capitalist norms.  相似文献   
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The information supplied by National Representatives has been supplemented from other sources. Readers are urged to send information, press releases, exhibition catalogues, etc., directly to the Chronicle Editor, Imago Mundi, 76 Ockendon Road, London N1 3NW, UK (), so that the next Chronicle can be as complete as possible. Chronicle considers all information that is current or historical at its closing date. No forthcoming events are included.  相似文献   
179.
Sadler, T., Kroh, A. &; Gallagher, S.J., March 2016. A review of the taxonomy and systematics of the echinoid genus Monostychia Laube, 1869 Laube, G.C., 1869. Über einige fossile Echiniden von den Murray Cliffs in Süd-Australien. Sitzungsberichte der Kaiserlichen Akademie der Wissenschaften zu Wien, mathematisch-naturwissenschaftliche Classe. Abtheilung I 59, 183198. [Google Scholar]. Alcheringa 40, xxx–xxx. ISSN 0311-5518

A review of Monostychia, a stratigraphically important clypeasteroid echinoid genus in southern Australian Oligocene/Miocene strata, reveals uncertainty in relation to morphological features used in taxonomy. The result is that the exact systematic position of the genus remains unresolved at subfamily level. Monostychia and its type species, M. australis, are redescribed. Monostychia australis is restricted to the lower to middle Miocene Glenforslan Formation of the Murray Basin. Three other species currently within Monostychia, M. etheridgei, M. loveni and M. elongata, are discussed. Although it is concluded that M. etheridgei belongs in the genus and is a distinct species, the taxonomic position of M. loveni is questioned, and the validity of M. elongata as a separate species from M. australis remains uncertain. This work lays the foundation for further revisions of Monostychia with an expectation that such work will provide the basis for character determination that may be useful across other echinoid taxa.

Tony Sadler [] and Stephen J. Gallagher [], School of Earth Sciences, University of Melbourne, Victoria 3010, Australia; Andreas Kroh [], Natural History Museum Vienna, Department of Geology and Palaeontology, Burging 7, 1010, Vienna, Austria.  相似文献   
180.
Temperate rainforest is restricted to a globally rare set of climatic conditions. Scotland has among the best remaining examples of intact temperate rainforest in Europe, characterised ecologically by a unique assemblage of epiphytic bryophytes and lichens. Given climatic control on rainforest distribution and ecology, climate change is a probable risk to Scotland’s rainforest. This study investigated climate change impacts for 20 target sites, classified based on (i) bioclimatic conditions, and (ii) epiphytic diversity, into contrasting rainforest and more continental (non-rainforest) examples. Space-for-time matching identified climate analogues within the European conservation forest network, which at present have a climate similar to that expected of the target sites during the 2080s (WorldClim datasets). The results show that 2080s analogues for sites in more continental north-eastern Scotland occur in Wales and southern England. However, Scottish rainforest sites were their own ‘best analogues’ through to the 2080s, despite the fact that their climate is projected to change significantly; they had no suitable future analogue within Europe’s conservation forest network. These contrasting regional patterns highlight the need for a flexible approach to species conservation during climate change, including a strategy to cope with ecological uncertainty in Scotland’s zone of oceanic rainforest.  相似文献   
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