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51.
Much academic research and industrial development explores new ways to create greener and environmentally friendlier chemicals and materials for a variety of applications. A significant part of this work focuses on the development, processing and manufacturing, recycling and disposal of green plastics, adhesives, polymer composites, blends and many other industrial products from renewable resources. Natural fibres offer the potential to deliver greater added value, sustainability, renewability and lower costs especially in the automotive industry. Further research involves the fibre crop production. The ever-increasing volume of scientific literature refers with enthusiasm to the potential of natural fibres in technological, economic and ecological terms. This enthusiasm tends to also expand to the areas of human life and socio-economic development for the fibre crop growers and their communities. However, there is very little debate or evidence to support statements about the assumed advantages for the affected population in rural areas. We argue that despite the predicted new boom in the demand of natural fibres, it is unlikely that this will represent a real improvement in the quality of life of crop fibre growers and their communities. This paper examines the experience of Mexico as a case study and argues that only through consistent political will and co-operation between governments, industry, scientists, consumer groups and local communities, as well as a suitable economic strategy such as local subsidies, a truly sustainable economic development, social equity and improved environmental quality will be achieved for tens of thousands of natural fibre growers.  相似文献   
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Although forest carbon offsets can play an important role in the implementation of comprehensive climate policy, they also face an inherent risk of reversal. If such risks are positively correlated across projects, it can affect the integrity of larger project portfolios and potentially the entire offsets program. Here, we discuss three types of risks that could affect forest offsets—fat tails, micro-correlation, and tail dependence—and provide examples of how they could present themselves in a forest offset context. Given these potential dependencies, we suggest several new risk management approaches that take into account dependencies in reversal risk across projects and which could help guard the climate integrity of an offsets program. We also argue that data collection be included as an integral part of any offsets program so that disturbance-related dependencies may be identified and managed as early and to the greatest extent possible.  相似文献   
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Marine fisheries in coastal ecosystems in many areas of the world have historically removed large-bodied individuals, potentially impairing ecosystem functioning and the long-term sustainability of fish populations. Reporting on size-based indicators that link to food-web structure can contribute to ecosystem-based management, but the application of these indicators over large (cross-ecosystem) geographical scales has been limited to either fisheries-dependent catch data or diver-based methods restricted to shallow waters (<20 m) that can misrepresent the abundance of large-bodied fished species. We obtained data on the body-size structure of 82 recreationally or commercially targeted marine demersal teleosts from 2904 deployments of baited remote underwater stereo-video (stereo-BRUV). Sampling was at up to 50 m depth and covered approximately 10,000 km of the continental shelf of Australia. Seascape relief, water depth, and human gravity (i.e., a proxy of human impacts) were the strongest predictors of the probability of occurrence of large fishes and the abundance of fishes above the minimum legal size of capture. No-take marine reserves had a positive effect on the abundance of fishes above legal size, although the effect varied across species groups. In contrast, sublegal fishes were best predicted by gradients in sea surface temperature (mean and variance). In areas of low human impact, large fishes were about three times more likely to be encountered and fishes of legal size were approximately five times more abundant. For conspicuous species groups with contrasting habitat, environmental, and biogeographic affinities, abundance of legal-size fishes typically declined as human impact increased. Our large-scale quantitative analyses highlight the combined importance of seascape complexity, regions with low human footprint, and no-take marine reserves in protecting large-bodied fishes across a broad range of species and ecosystem configurations.  相似文献   
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Continuous production processes on North Sea installations necessitate extended work schedules; 2-week offshore tours (alternating with shore breaks), 12 h shifts and rapid day/night shift changes are inherent features of offshore work. These intensive rosters, worked in a demanding physical and psychosocial environment, are potential sources of fatigue and impaired performance among offshore personnel. This article focuses on offshore working time arrangements, and presents a systematic review of studies which examine offshore day/night shift patterns in relation to operational safety and individual health risks. Of the 53 studies retrieved, 24 met the review criteria.Field study findings are generally consistent in showing that sleep, alertness and performance are relatively stable across day-shift tours; initial night shifts are adversely affected by circadian disruption, but full physiological and psychological adaptation occurs within 5–6 days; re-adaptation to day shifts is slower, and varies widely across individuals; the offshore environment is conducive to night-shift adaptation, but interventions to facilitate re-adaptation have proved only modestly effective. Analyses of survey data and accident/sickness records identify offshore night work as a risk factor for impaired sleep, health problems, and injuries, but little is known about the long-term health effects of different offshore shift rotations.In conclusion, research methodology and findings, and working time issues of current concern to the offshore oil/gas industry, are discussed. Aspects of offshore work schedules that have been not been widely studied (e.g. overtime, irregular work patterns) are also highlighted, and research areas that would merit further attention are noted.  相似文献   
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Habitat shifts play an important role in structuring faunal assemblages; however, research has focused on the influence of random disturbance events and information on how regular seasonal changes to habitat affect marine fauna remains largely unexplored, especially in the tropics. We recorded seasonal changes in the structure of tropical macroalgae fields within the Ningaloo lagoon (Western Australia) and related this to the density, biomass and species richness of fishes that represent key processes: juveniles, predators of juveniles and herbivores. The extent and direction of seasonal changes in macroalgae were inconsistent among sites, creating a highly dynamic habitat matrix across time and space. Species richness and density of fishes were largely maintained where density of holdfasts from canopy-forming macroalgae and/or cover was high across seasons, but shifted markedly in areas of macroalgae habitat loss: suggesting stable habitat structure is critical for the persistence of macroalgae-associated fishes. Our results demonstrate that macroalgae fields that maintain high structural complexity across different seasons are more likely to preserve key ecological processes and therefore warrant greater conservation attention within a spatial management framework.  相似文献   
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