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Adult Vinciguerria nimbaria are the main prey of tuna during the tuna fishing season (late autumn and winter) in the equatorial Atlantic (0–4°N, and ~15°W). V. nimbaria trophic behavior in the fishing grounds was studied in relation to hydrobiological factors to determine its role in the trophic food web. Sampling stations spaced by 20 nautical miles were set up along a 15°W north–south transect from 4°N to 0°40S. At each station, the temperature and vertical fluorescence profiles were recorded. Nitrate and chlorophyll a analyses were performed on water sampled at different levels in the euphotic zone. Vertical plankton hauls were carried out at depths of 0–100 and 0–200 m using a standard WP2 net fitted with a 200-μm mesh gauze. Vinciguerria nimbaria adults were collected using a young-fish mid-water trawl net (10 × 15 m opening mouth, 10 mm cod end mesh). The weight of the stomach contents, the stomach fullness index, the number of prey, the frequency of occurrence and the prey preponderance were recorded for 20 fish from each haul. An oligotrophic typical tropical structure (TTS) was found between 1° and 4°N where small zooplankton was relatively abundant above or near the thermocline. In the TTS, V. nimbaria behaved as an epipelagic fish, feeding on the dominant small prey during the daytime. In turn, it was a prey for tuna. In the equatorial zone, where zooplankton was more abundant than in the north equatorial zone, V. nimbaria behaved as a mesopelagic fish and as an opportunistic mesozooplankton feeder. It consumed a wide range of sizes of food, feeding on the most abundant species of zooplankton as well as the largest zooplankton species, possibly while migrating towards the surface in the late afternoon or in the deep layer.  相似文献   
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ABSTRACT

Climate change is expected to contribute to global inequality, and exacerbate ecological risk for the world's poor. Despite recent trends within waste management academic discourse, which has begun to engage with inequality, and its underlying socio-economic and socio-political causes, discussions of inequality have so far remained absent from our investigations on climate change's impacts on waste management systems and practices. The purpose of the discussion is to call for a centring of inequality within our waste and climate discourse. I identify two main pathways for scholarly investigation, specifically, developing alternative waste management solutions for contexts in which waste management systems fail, which do not just perpetuate existing inequalities, and addressing the growing inequality in waste management technology and practice between the Global North and the Global South.  相似文献   
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For governments and for manufacturing companies, global warming, rising energy prices, and customers’ increasing ecological awareness have pushed energy efficient manufacturing to the top of the agenda. Governments and companies are both striving to identify the most effective measures to increase energy efficiency in manufacturing processes. Based on results of a recent EU-funded roadmapping project, this paper highlights the needs of industrial companies for integrating energy efficiency performance in production management. First, it analyses concepts and tools for measurement, control and improvement of energy efficiency in production management proposed in literature. Second, the paper outlines that ICT tools and standardization are important enablers for energy efficient manufacturing. Third, industrial needs in these areas are presented based on expert interviews. The industrial needs thus identified are contrasted with concepts proposed in literature to point out the implementation gaps between practice and theory. The paper demonstrates that there exists a gap between the solutions available and the actual implementation in industrial companies. It concludes by deriving requirements for energy management in production that future collaborative research projects should address.  相似文献   
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Despite the reported benefits of conservation agriculture (CA), its wider up-scaling in Sub-Saharan Africa (SSA) has remained fairly limited. This paper shows how a newly developed qualitative expert assessment approach for CA adoption (QAToCA) was applied to determine its adoption potential in SSA. CA adoption potential is not a predictor of observed adoption rates. Instead, our aim was to systematically check relevant factors that may be influencing its adoption. QAToCA delivers an assessment of how suitable conditions “and thus the likelihood for CA adoption” are. Results show that the high CA adoption potentials exhibited by the Malawi and Zambia case relate mostly to positive institutional factors. On the other hand, the low adoption potential of the Zimbabwe case, in spite of observed higher estimates, is attributed mainly to unstable and less secured market conditions for CA. In the case of Southern Burkina Faso, the potential for CA adoption is determined to be high, and this assessment deviates from lower observed figures. This is attributed mainly to strong competition of CA and livestock for residues in this region. Lastly, the high adoption potential found in Northern Burkina Faso is explained mainly by the fact that farmers here have no alternative other than to adopt the locally adapted CA system—Zaï farming. Results of this assessment should help promoters of CA in the given regions to reflect on their activities and to eventually adjust or redesign them based on a more explicit understanding of where problems and opportunities are found.  相似文献   
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Environmental Chemistry Letters - Alkylphenols and alkylphenol polyethoxylates are emerging hazardous contaminants due in particular to their endocrine-disrupting properties. These compounds...  相似文献   
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Environmental Science and Pollution Research - Since the establishment of the coastal industrial complex in Gabes city (Gulf of Gabes, SE Tunisia), hundred million tons of untreated phosphogypsum...  相似文献   
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