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The “Tsesis” oil spill in October 1977 resulted in the release of over 1 000 tons of medium grade fuel oil in an archipelago in the brackish Baltic Sea. Considerable oil quantities reached the benthos by sedimentation. Within 16 d benthic amphipods of the genus Pontoporeia, as well as the polychaete Harmothoe sarsi Kinberg, showed reduction to less than 5% of pre-spill biomasses at the most impacted station. The clam Macoma balthica (L.) was more resistant, and showed little or no mortality, but was heavily contaminated by oil (about 2 000 μg g-1 dry wt total hydrocarbons). The meiofauna was strongly affected, with ostracods, harpacticoids, Turbellaria and kinorhynchs showing clear reductions in abundance, while nematodes, as a group, were more resistant. In the winter following the spill gravid Pontoporeia affinis Lindström females showed a statistically significant increase in the frequency of abnormal or undifferentiated eggs. Food-chain transfer of oil to flounder [Platichthys flesus (L.)] was indicated. Not until the second summer after the spill were the first signs of recovery noted at the most heavily impacted station: Amphipods, H. sarsi and harpacticoids increased and the oil concentrations in M. balthica decreased (to about 1 000 μg g-1). In the area where amphipods had been virtually eliminated, there was an unusually heavy recruitment of M. balthica, reaching 4 000 juveniles, of 1.5–2 mm length, per square metre, probably from settling in summer 1978. Three years after the spill Pontoporeia spp. biomass was still depressed in the most affected area, while H. sarsi showed normal biomass, and M. balthica abundance was inflated. Oil concentrations in M. balthica (about 250 μg g-1) and flounder were only slightly elevated and the oil could no longer be confidently ascribed to “Tsesis” origin, even using GC/MS-analysis. Recovery was thus underway, but the long lifespan of M. balthica implies that the disturbed community composition may persist for many years at this station. Full recovery is likely to require more than 5 yr and may take a decade or more. An effort to evaluate the accumulated monetary loss to fishery from the accident indicates that direct costs of shoreline cleanup and vessel damage were considerably greater.  相似文献   
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LKAB Malmberget is a Swedish mining site located at Malmberget, Sweden. Seven boiler centers are located in the north part of Malmberget. There are no connections in between these boiler centers, meaning that it is a decentralized heating system. The heat generated is used to heat up buildings and for mine ventilation air mainly during the cold periods. The heat is mainly provided from electric and oil boilers. However, most boilers under use are over 20 years old, and it is time to retrofit the boiler system and infrastructure. The purpose of this work is to design and optimize the heating system by introducing an integrated concept to minimize the heat production cost.An optimization model based on the mixed integer linear programming (MILP) has been developed. Several technical options have been considered in a new centralized heating system. The optimization principle is based on two kinds of perspectives: current price and external costs. With consideration of environmental and health damage from society concerns point of view, instead of environmental taxes in the current price perspective, the monetary values of externalities due to pollutants such as CO2, NOx, SO2 and particulates emitted from the heating system are included. On the basis of data input and assumptions, modeling results indicate that a lower cost could be achieved when a waste heat recovery boiler is installed at the older pelletization plant to recover sensible heat from flue gas. This technical option is the best solution or at least contributes to the best solution in all optimization results. Including the externality cost is useful for making fair evaluation of the social-environmental impacts of the alternatives.  相似文献   
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Environmental Economics and Policy Studies - There is an urgent need for the development of environmentally sustainable products market in developing economies, particularly in South Africa due to...  相似文献   
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In public debates, agricultural biotechnology is almost invariably discussed as a potential threat to the environment and to human health. Without downplaying the risks associated with this technology we emphasize that if properly regulated, it can be a forceful tool to solve environmental problems and promote human health. Agricultural biotechnology can reduce environmental problems in at least three ways: it can diminish the need for environmentally damaging agricultural practices such as pesticides, fertilizers, tillage, and irrigation. It can reduce the land area needed for agriculture, thus reducing the CO2 effect of agriculture and improving biodiversity. It can produce energy in a CO2-neutral way (especially if new technologies involving the cultivation of microalgae become successful). Furthermore, agricultural biotechnology can have positive effects on human health by decreasing occupational and dietary exposure to pesticides, improving the nutritional value of food, and producing pharmaceuticals more efficiently. We argue that those who wish to give high priority to environmental goals cannot afford any longer to be mere onlookers while others decide the future directions of agricultural biotechnology.  相似文献   
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As policy makers and funders have become more concerned with allocating scarce resources effectively, attention to the sustainability of health intervention programs has increased. However, the empirical knowledge base about factors facilitating or working against sustainability remains at an early stage. The aim of this study was to contribute to improved understanding of the conditions under which community-based injury prevention programs are most likely to attain sustainability. Ten Swedish community-based injury prevention programs were analysed with respect to factors that contribute to or detract from program sustainability. All the programs are integrated within existing municipality structures. Data were collected by means of semi-structured telephone interviews with key informants.The results suggested that different factors are interrelated, with no one factor being either primary or by itself sufficient for program sustainability. Financial, human, and relational resources lay the groundwork for the long-term operation of a program. The “integrated” program model appears to facilitate sustainability, but program intensity is vulnerable to changes in the financial status of the municipality and the priority-setting by municipality political decision makers. Sustainability may be compromised if a program becomes too dependent on a few key individuals. In contrast to financial, human, and relational resources, structural resources (e.g., injury surveillance and goals) appeared to have limited influence on sustainability. The programs were sustained with little evidence of effectiveness, resulting in limited feedback about how to improve a program in order to achieve and maintain long-term effectiveness.  相似文献   
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The diet of cavity sponges on the narrow fringing reefs of Curaçao, Caribbean was studied. The origin and resources of the bulk food of these sponges, i.e., dissolved organic matter (DOM), were identified using stable carbon and nitrogen isotopes and fatty acid biomarkers. We found that phytoplankton and its derived DOM from the adjacent open sea and from reef overlying water is not the main source of food for most of the sponges examined nor is bacterioplankton. Interestingly, dual stable isotope signatures (δ13Corg, δ15Norg) and fatty acid biomarkers appoint coral mucus and organic matter derived from crustose coralline algae (CCA) as probable food sources for encrusting sponges. Mucus-derived DOM may contribute up to 66% to the diet of examined sponges based on results of dual isotope mixing model analysis. The contribution of CCA (as purported representative for benthic algae) was smaller with values up to 31%. Together, mucus- and CCA-derived substrates contributed for 48–73% to the diet of sponges. The presence of the exogenous fatty acid 20:4ω6 in sponges, which is abundant in coral mucus of Madracis mirabilis and in CCA, highlights these reef-derived resources as sources of nutrition for DOM feeding cavity sponges. The relatively high concentrations of exogenous 20:4ω6 in all sponges examined supports our hypothesis that the bulk of the food of the cavity sponge community is reef-derived. Our results imply that cavity sponges play an important role in conserving food and energy produced within the reef.  相似文献   
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针对欧洲化学品管理系统REACH的数据要求,本文提出许多改进建议.要实施根据物质的有害作用进行分类的当前标准,这些数据要求显得不足.在数据收集中以产量作为优先制定的标准,这是成问题的.提出了优先制定机制的三项替代建议:物质的化学性质:低层次检测的结果;对自动检测的激励.一个新的分类办法(未充分研究)亦被提出.在这个办法里,物质将根据警示标识予以鉴别.  相似文献   
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