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Lately, the technical research on carbon dioxide capture and utilization (CCU) has achieved important breakthroughs. While single CO2-based innovations are entering the markets, the possible economic effects of a large-scale CO2 utilization still remain unclear to policy makers and the public. Hence, this paper reviews the literature on CCU and provides insights on the motivations and potential of making use of recovered CO2 emissions as a commodity in the industrial production of materials and fuels. By analyzing data on current global CO2 supply from industrial sources, best practice benchmark capture costs and the demand potential of CO2 utilization and storage scenarios with comparative statics, conclusions can be drawn on the role of different CO2 sources. For near-term scenarios the demand for the commodity CO2 can be covered from industrial processes, that emit CO2 at a high purity and low benchmark capture cost of approximately 33 €/t. In the long-term, with synthetic fuel production and large-scale CO2 utilization, CO2 is likely to be available from a variety of processes at benchmark costs of approx. 65 €/t. Even if fossil-fired power generation is phased out, the CO2 emissions of current industrial processes would suffice for ambitious CCU demand scenarios. At current economic conditions, the business case for CO2 utilization is technology specific and depends on whether efficiency gains or substitution of volatile priced raw materials can be achieved. Overall, it is argued that CCU should be advanced complementary to mitigation technologies and can unfold its potential in creating local circular economy solutions.  相似文献   
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About 3600 tonnes food waste are discarded in the landfills in Hong Kong daily. It is expected that the three strategic landfills in Hong Kong will be exhausted by 2020. In consideration of the food waste management environment and community needs in Hong Kong, as well as with reference to the food waste management systems in cities such as Linköping in Sweden and Oslo in Norway, a framework of food waste separation, collection, and recycling for food waste valorization is proposed in this paper. Food waste can be packed in an optic bag (i.e., a bag in green color), while the residual municipal solid waste (MSW) can be packed in a common plastic bag. All the wastes are then sent to the refuse transfer stations, in which food waste is separated from the residual MSW using an optic sensor. On the one hand, the sorted food waste can be converted into valuable materials (e.g., compost, swine feed, fish feed). On the other hand, the sorted food waste can be sent to the proposed Organic Waste Treatment Facilities and sewage treatment works for producing biogas. The biogas can be recovered to produce electricity and city gas (i.e., heating fuel for cooking purpose). Due to the challenges faced by the value-added products in Hong Kong, the biogas is recommended to be upgraded as a biogas fuel for vehicle use. Hopefully, the proposed framework will provide a simple and effective approach to food waste separation at source and promote sustainable use of waste to resource in Hong Kong.  相似文献   
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Throughout the world there is a general consensus among environmentalists that there should be an increase in the amount of marine area that should be reserved in marine protected areas (MPAs). In fact, the 1998 Philippines Fishery Code indicates a need for designation of at least 15% of municipal waters for fish refuges or sanctuaries. Such an increase in area would take productive fishing areas away from fishing communities that can ill-afford the loss. The larger the protected area, there will be a greater number of people impacted. This article examines the relationship between factors that influence the success of Community Based MPA (CBMPA) performance in the Visayas, Philippines and their significance in efforts to increase the size of protected areas.  相似文献   
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Oysters contaminated with norovirus present a significant public health risk when consumed raw. In this study, norovirus genome copy concentrations were determined in Pacific oysters (Magallana gigas) harvested from a sewage-impacted production site and then subjected to site-specific management procedures. These procedures consisted of relocation of oysters to an alternative production area during the norovirus high-risk winter periods (November to March) followed by an extended depuration (self-purification) under controlled temperature conditions. Significant differences in norovirus RNA concentrations were demonstrated at each point in the management process. Thirty-one percent of oyster samples from the main harvest area (Site 1) contained norovirus concentrations >?500 genome copies/g and 29% contained norovirus concentrations <?100 genome copies/g. By contrast, no oyster sample from the alternative harvest area (Site 2) or following depuration contained norovirus concentrations >?500 genome copies/g. In addition, 60 and 88% of oysters samples contained norovirus concentrations <?100 genome copies/g in oysters sampled from Site 2 and following depuration, respectively. These data demonstrate that site-specific management processes, supported by norovirus monitoring, can be an effective strategy to reduce, but not eliminate, consumer exposure to norovirus genome copies.  相似文献   
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Southern Chile encompasses one of the most extensive fjord regions of the world, the Patagonia, currently exposed to natural and anthropogenic perturbations. These fjord ecosystems provide important services to humans, which have not been adequately measured and valued. As a consequence, ecosystem services are commonly ignored in public policy design and in the evaluation of development projects. Here we tackle questions that are highly relevant for the nation’s development, namely (1) understanding fjord functioning, and (2) developing management strategies based on ecosystem services, in order to secure simultaneous and adequate use of these ecosystems which area influenced by ecological (e.g., biogeochemical) and productive (e.g., aquaculture, fisheries) processes. We also seek to strengthen the analysis of fjord ecosystem value from the economical (including coastal zoning), socio-cultural, institutional, and governmental points of view. In addition, the investigation of current and future effects of climate change on this large region offers a unique opportunity to understand the social and economic consequences of a global phenomenon at local to regional scales. Biogeochemical and socio-economic models will be used to simulate future scenarios under a gamut of management options.  相似文献   
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Biomarkers are internationally recognized as useful tools in marine coastal biomonitoring, in particular, as early-warning signals at the level of individual organisms to assess biological effects of pollutants and other stressors. In the present study, Mytilus galloprovincialis has been employed as a sentinel organism to assess biological pollution effects in the Mar Piccolo of Taranto (Southern Italy), a coastal lagoon divided into two small inlets, connected to the open sea through one natural and one artificial narrow openings. Mussels were collected in June 2013 at three sites located within each of the two inlets of the Mar Piccolo. Biological effects were investigated through a suite of biomarkers suitable to reflect effects and/or exposure to contaminants at biochemical and cellular levels. Biochemical biomarkers included glutathione-S-transferase (GST) and acetylcholinesterase (AChE) enzyme activities; as histochemical biomarkers, lysosomal membrane stability, lipofuscin and neutral lipid accumulation, and lysosomal structural changes were considered. As a whole, results highlighted differences among the three study sites, particularly for GST, AChE, and lipofuscins, which are consistent with the variations of the chemical pollutants in sediments. The applied biomarkers showed that a stress syndrome likely to be ascribed to environmental pollutants is occurring in mussels living in the Mar Piccolo of Taranto, in particular, the ones inhabiting the first inlet.  相似文献   
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