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51.
The general public in Europe seems tohave lost its confidence in food safety. Theremedy for this, as proposed by the Commissionof the EU, is a scientific rearmament. Thequestion, however, is whether more science willbe able to overturn the public distrust.Present experience seems to suggest thecontrary, because there is widespread distrustin the science-based governmental controlsystems. The answer to this problem is thecreation of an independent scientificFood Authority. However, we argue thatindependent scientific advice alone is unlikelyto re-establish public confidence. It is muchmore important to make the scientific advicetransparent, i.e., to state explicitlythe factual and normative premises on which itis based. Risk assessments are based on arather narrow, but well-defined notion of risk.However, the public is concerned with a broadervalue context that comprises both benefits andrisks. Transparency and understanding of thepublic's perception of food risks is anecessary first step in establishing theurgently required public dialogue about thecomplex value questions involved in foodproduction.  相似文献   
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Strategies are needed to increase the sustainability of phosphorus (P) fertiliser management in agriculture. This paper reports on the potential of pyrolysis treatment to recycle P from renewable materials previously regarded as wastes. The study used K-edge X-ray absorption near-edge structure (XANES) spectroscopy to examine chemical forms of P in the waste feedstock materials and corresponding biochars (pyrolysis at 480–500 °C) of four ligno-cellulosic, plant-based residues and five relatively P-rich livestock and water-treatment by-products, to acquire information on changes in potential P fertiliser value. Pyrolysis enriched P in the biochars by factors of 1.3–4.3, thus offering wide-ranging P fertiliser potential. XANES spectroscopy revealed hydroxyapatite (HAP) as one of the dominant chemical P compounds in the feedstocks, ranging from 14% (rice husks) to 98% (animal bone) of total P. For most materials, pyrolysis increased the proportion of HAP, and pyrophosphates were generated in several cases. These alterations possibly lead to diversity in the P solubility characteristics of the biochars if used as soil amendments; this is an important property of environmentally sound P fertilisers.  相似文献   
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This study investigates over 30 years of dissolved oxygen dynamics in the deep interior of Lake Constance (max. depth: 250 m). This lake supplies approximately four million people with drinking water and has undergone strong re-oligotrophication over the past decades. We calculated depth-specific annual oxygen depletion rates (ODRs) during the period of stratification and found that 50% of the observed variability in ODR was already explained by a simple separation into a sediment- and volume-related oxygen consumption. Adding a linear factor for water depth further improved the model indicating that oxygen depletion increased substantially along the depth. Two other factors turned out to significantly influence ODR: total phosphorus as a proxy for the lake’s trophic state and mean oxygen concentration in the respective depth layer. Our analysis points to the importance of nutrient reductions as effective management measures to improve and protect the oxygen status of such large and deep lakes.  相似文献   
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Commuting partners, dual residences and the meaning of home   总被引:1,自引:0,他引:1  
The experience of home is one of the most basic of daily-life experiences. Traditionally, the home is grounded in a specific place; in commuter partnerships, however, for part of the time one partner lives near the workplace and away from the family residence. This paper provides insight into the sense of home that relates to the dual-residence situation of a commuter partnership. The meaning of the residence near the workplace is analysed through three dimensions: material, activity patterns, and social. We further classified each dimension in a continuum of meanings of space, place or home. Empirical evidence comes from in-depth interviews with 30 commuter couples in the Netherlands. The results show that the material dimension is most often used to create a sense of home. The activity patterns are primarily focused on the job. The social dimension is the most difficult way of experiencing a home because there is yet a strong relationship between being with one's family and experiencing a sense of home. As a result, many feel as living two separated lives: a work life and a private life. Only a small minority experiences the commuter dwelling as a home away from home in all its three dimensions.  相似文献   
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Managing Watershed Externalities in India: Theory and Practice   总被引:2,自引:0,他引:2  
Watershed development is the focus of poverty alleviation programs in rural India. Watershed projects aim to solve problems of externalities, but they also create their own externalities, which cause uneven distribution of costs and benefits that undermine project objectives and harm the poor. Numerous approaches exist to internalize externalities, including awareness creation, moral suasion, investment subsidies, regulatory limits and fines, indirect benefits, mergers, and recent innovations like payment for environmental services and cap and trade. These can be judged on several criteria; the best approach would solve the problem cost effectively and help or at least not hurt poor people. Watershed projects in India were examined to identify the approaches taken to internalize watershed externalities. Investment subsidies and indirect employment benefits are the least effective approaches theoretically, but they are the most commonly applied, most likely because they are easy to administer and bring popular short term gains. Some theoretically favorable approaches that have been used elsewhere, such as payment for environmental services, may not work as well in India due to high transaction costs. However, one key innovation that easily could be applied in India is to make investment subsidies contingent on performance. Legal support and property rights reform would be needed for other favorable approaches.  相似文献   
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Landfill leachates sampled during and after an accidental landfill fire were analysed and the levels of selected metals and chemical compounds compared to those occurring in the leachate under normal conditions. The fire at the landfill site was put out by excavation and cooling by use of water. The investigation during the fire and fire fight revealed a moderate increase in the level of nitrogen and also in pH and conductivity. Heavy metals and COD in the leachate showed considerably increased levels. In general, the determined variables appeared to normalise within one week after the fire was extinguished. It can be concluded that landfill fires extinguished by excavation may lead to elevated leachate levels of especially COD and heavy metals, but that this is only a short-term effect.  相似文献   
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