129 research outputs found

    New primary production in northwest European shelf seas, 1960–2003

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    Spatial and temporal patterns from 1960 to 2003 in annual potential new primary production (PNP) of the NW European shelf seas were derived from general additive models of nitrate concentrations and from data on riverine and atmospheric fluxes of oxidized nitrogen. Average PNP was highest in the seasonally stratified outer shelf regions (>70 gC m-2 yr-1), where the proportion of PNP accounted for by vertical fluxes from deep water (>65%) was correlated with the North Atlantic Oscillation (NAO) index. PNP was lowest in the central North Sea (~30 gC m-2 yr-1) and in the southern North Sea was correlated with river inputs that accounted for 24% of the annual total (average ~50 gC m-2 yr-1). Atmospheric deposition accounted for ~3% of annual PNP region-wide, but in the northern North Sea this was higher than the contribution from rivers. Tidal fronts are traditionally considered to be highly productive zones, but we find them to have characteristically low PNP and conclude that they must be loci of high recycled production. The results indicate an exceptional flux of nitrate-rich ocean water onto the shelf in the early 1990s, which resulted in a pulse of PNP coincident with a well-documented 'regime shift' in the pelagic food web. North Sea-wide, long-term average PNP was approximately equal to production by all higher trophic levels combined, though trophic propagation of inter-annual variations was weakly defined. Nevertheless, there is a case for proposing that harvesting in areas and periods of low PNP should be managed more conservatively to minimize the risk of detrimental effects on the food web

    Origin of the TTC values for compounds that are genotoxic and/or carcinogenic and an approach for their revaluation

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    The threshold of toxicological concern (TTC) approach is a resource-effective de minimismethod for the safety assessment of chemicals, based on distributional analysis of the results of a large number of toxicological studies. It is being increasingly used to screen and prioritise substances with low exposure for which there is little or no toxicological information. The first step in the approach is the identification of substances that may be DNA-reactive mutagens, to which the lowest TTC value is applied. This TTC value was based on analysis of the cancer potency database and involved a number of assumptions that no longer reflect the state-of-the-science and some of which were not as transparent as they could have been. Hence, review and updating of the database is proposed, using inclusion and exclusion criteria reflecting current knowledge. A strategy for the selection of appropriate substances for TTC determination, based on consideration of weight of evidence for genotoxicity and carcinogenicity is outlined. Identification of substances that are carcinogenic by a DNA-reactive mutagenicmode of action and those that clearly act by a non-genotoxic mode of action will enable the protectiveness to be determined of both the TTC for DNA-reactive mutagenicityand that applied by default to substances that may be carcinogenic but are unlikely to be DNA-reactive mutagens (i.e. for Cramer class I-III compounds). Critical to the application of the TTC approach to substances that are likely to be DNA-reactive mutagens is the reliability of the software tools used to identify such compounds. Current methods for this task are reviewed and recommendations made for their application

    Mapping the Future: Policy Applications of Climate Vulnerability Mapping in West Africa

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    We describe the development of climate vulnerability maps for three Sahelian countries – Mali, Burkina Faso, and Niger – and for coastal West Africa, with a focus on the way the maps were designed to meet decision-making needs and their ultimate influence and use in policy contexts. The paper provides a review of the literature on indicators and maps in the science-policy interface. We then assess the credibility, salience, and legitimacy of the maps as tools for decision-making. Results suggest that vulnerability maps are a useful boundary object for generating discussions among stakeholders with different objectives and technical backgrounds, and that they can provide useful input for targeting development assistance. We conclude with a discussion of the power of maps to capture policy maker attention, and how this increases the onus on map developers to communicate clearly uncertainties and limitations. The assessment of policy uptake in this paper is admittedly subjective; the article includes a discussion of ways to conduct more objective and rigorous assessments of policy impact so as to better evaluate the value and use of vulnerability mapping in decision-making processes

    Strengths-Weaknesses-Opportunities-Threats analysis of carbon footprint indicator and derived recommendations

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    ABSTRACT: Demand for a low carbon footprint may be a key factor in stimulating innovation, while prompting politicians to promote sustainable consumption. However, the variety of methodological approaches and techniques used to quantify life-cycle emissions prevents their successful and widespread implementation. This study aims to offer recommendations for researchers, policymakers and practitioners seeking to achieve a more consistent approach for carbon footprint analysis. This assessment is made on the basis of a comprehensive Strengths-Weaknesses-Opportunities-Threats or SWOT Analysis of the carbon footprint indicator. It is carried out bringing together the collective experience from the Carbonfeel Project following the Delphi technique principles. The results include the detailed SWOT Analysis from which specific recommendations to cope with the threats and the weaknesses are identified. In particular, results highlight the importance of the integrated approach to combine organizational and product carbon footprinting in order to achieve a more standardized and consistent approach. These recommendations can therefore serve to pave the way for the development of new, specific and highly-detailed guidelines
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