114 resultados para Agricultural price supports


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Existing in suboptimal conditions is a frequent occurrence for species inhabiting the cusp of their ecological range. In range-edge populations of plants, the scarcity of suitable habitat may be reflected in small population sizes which may result in increased self-pollination and/or inbreeding and an increase in the incidence of clonal reproduction. These factors may result in a decrease in levels of genetic diversity and a loss of potential adaptive variation that may compromise species' ability to cope with changes in their environment, an issue that is particularly relevant today with the current concern surrounding global climate change and its effect on species' distributional ranges. In the present study, we have compared the levels of clonal reproduction in the one-sided wintergreen Orthilia secunda (L.) House in (1) populations from its main continuous distribution range, (2) populations occurring on the limits of the continuous range, and (3) peripheral populations outwith the species' continuous distribution range. Range-edge populations in Scotland and Sweden displayed significantly lower genotypic richness and diversity than those from the main area of the species' distribution in these countries. Populations from Ireland, which occur in the temperate zone rather than the boreal conditions that are the preferred habitat for the species, and which represent relict populations left over from cooler periods in the Earth's history, displayed no within-population genetic diversity, suggesting a complete lack of sexual reproduction. Furthermore, the genetic distinctiveness of the Irish populations, which contained alleles not found in either the Scottish or the Swedish populations, highlights the value of 'trailing edge' populations and supports the concept of 'parochial conservation', namely the conservation of species that are locally rare but globally common.

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The tribe Gymnothamnieae Kajimura was proposed for the monotypic ceramiacean genus Gymnothamnion J. Agardh, previously placed either in the Ptiloteae Cramer or the Antithamnieae Hommersand. A bisporangial isolate of G. elegans (Schousboe ex C. Agardh) J. Agardh from Morocco formed only bisporangia in culture. Its smaller uninucleate cells and sporangia than those of tetrasporophytes suggested that bisporophytes may be haploid as in another member of the Ceramiaceae, Aglaothamnion diaphanum L'Hardy-Halos et Maggs. Phylogenetic analyses of the gene for the large subunit of rubisco (rbcL) from Gymnothamnion and representatives of eight other tribes of the Ceramiaceae confirmed that the removal of Gymnothamnion from the Ptiloteae and the Antithamnieae was warranted. Whereas all tribes with two or more representatives in our analyses were moderately or robustly resolved, Gymnothamnion did not form a strong clade with any other taxa. Analysis of rbcL sequences failed to resolve relationships between tribes, probably due to saturation at the high levels of sequence divergence found. In addition to reproductive features previously reported and interpreted as primitive, G. elegans shows a primitive vegetative feature and it is suggested that Gymnothamnion may be one of the most basal of the taxa presently included in the Ceramiaceae.

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Aerogels containing palladium metal nanoparticles were prepared using an ionic liquid route and tested for activity towards hydrogenation and Heck C-C coupling reactions. (C) 2003 Elsevier B.V. All rights reserved.

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About 100 million rural people in Asia are exposed to arsenic (As)-polluted drinking water and agricultural products. Total and inorganic arsenic (t-As and i-As) intake mainly depend on the quality of drinking and cooking waters, and amounts of seafood and rice consumed. The main problems occur in countries with poor water quality where the population depends on rice for their diet, and their t-As and i-As intake is high as a result of growing and cooking rice in contaminated water. Workable solutions to remove As from water and breeding rice cultivars with low As accumulation are being sought. In the meantime, simple recommendations for processing and cooking foods will help to reduce As intake. For instance, cooking using high volumes of As-free water may be a cheap way of reducing As exposure in rural populations. It is necessary to consider the effects of cooking and processing on t-As and i-As to obtain a realistic view of the risks associated with intake of As in Asendemic areas.

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‘Rural stress’ and ‘farming stress’ are terms that have become commonly appropriated by British health-based academic disciplines, the medical profession and social support networks, especially since the agricultural ‘crises’ of B.S.E. and Foot and Mouth Disease. Looking beyond the media headlines, it is apparent that the terms in fact are colloquial catch-alls for visible psychological and physiological outcomes shown by individuals. Seldom have the underlying causes and origins of presentable medical outcomes been probed, particularly within the context of the patriarchal and traditionally patrilineal way of life which family forms of farming business activity in Britain encapsulate. Thus, this paper argues that insufficient attention has been paid to the conceptualization of the terms. They have become both over-used and ill-defined in their application to British family farm individuals and their life situations. A conceptual framework is outlined that attempts to shift the stress research agenda into the unilluminated spaces of the family farming ‘way of life’ and focus instead on ‘distress’. Drawing upon theorization from agricultural and feminist geography together with cultural approaches from rural geography, four distinct clusters of distress originate from the thoughts of individuals and the social practices now required to enact patriarchal family farming gender identities. These are explored using case study evidence from ethnographic repeated life history interviews with members of seven farming families in Powys, Mid Wales, an area dominated by family forms of farming business. Future research agendas need to be based firmly on the distressing reality of patriarchal family farming and also be inclusive of those who, having rejected the associated way of life, now lie beyond the farm gate.

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Until now, there has been little empirical evidence that EU Emissions Trading Scheme (ETS) transaction costs are incurred at firm level. The transaction costs (internal costs, capital costs, consultancy and trading costs) incurred by Irish firms under the EU ETS during its pilot phase (2005-2007) were measured and analysed. Evidence for the sources of transaction costs, their magnitude and the distribution of costs shows that these were mainly administrative in nature. Considerable variation in costs was found due to economies of scale, as the costs per tonne of CO2 were lower for participants with larger allocations. For the largest firms - accounting for over half the emissions - average transaction costs were €0.05 per tonne. However, for small firms, average transaction costs were €2.02 - over 18% of the current allowance price. This supports the concerns that transaction costs are excessive for smaller participants. The immediate policy implication is that additional attention will be needed to address different sizes of firms, number of installations per firm, and the size of the initial allocations.