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991.
Many national exposure programmes have been performed in tropical and subtropical climates during the last 50 years. However, ambitious programmes involving more than a few countries are scarce. In this paper a recently formed network of test sites is described involving 12 test sites in Asia (India, Vietnam, Thailand, Malaysia and China including Hong Kong) and four test sites in Africa (South Africa, Zambia and Zimbabwe). This effort is part of the 2001–2004 Swedish International Development Agency (SIDA) funded Programme on Regional Air Pollution in Developing Countries (RAPIDC). Corrosion attack after one (2002–2003) year of exposure (carbon steel, zinc, copper, limestone and paint coated steel) are presented together with environmental data (SO2, NO2, HNO3, O3, particles, amount and pH of precipitation, temperature and relative humidity) for all the test sites. The obtained corrosion values are substantially higher than expected for limestone, higher than expected for carbon steel and lower than expected for zinc compared to values calculated using the best available dose–response functions.  相似文献   
992.
This article reviews recent progress in material flow analysis and its use in providing resource productivity indicators and is based on developments in Japanese policy toward a sound material-cycle society and in international forums such as within the Organisation for Economic Development and Cooperation, covering both institutional and methodological issues. Indicators derived from economy-wide material flow accounts such as direct material inputs are useful to demonstrate the absolute size of a physical economy and to reinforce the need to both reduce consumption of natural resources and limit waste generation. Interpretation of material flows as resources and potential environmental impacts is discussed, and linkages between the size of material flows and specific environmental impacts and damage must be further elaborated for use in environmental policy. Lessons learned from the practical use of resource productivity indicators are also discussed. Additional indicators are needed that can be used to evaluate the performance of microeconomic contributors. The need for an integrated approach that links upstream resource issues and downstream waste issues through the 3Rs concept or the circular economy/society concept is attracting increasing attention. Consequently, the accumulation of reliable scientific knowledge and data in this field in a fully international context is essential.  相似文献   
993.
Polycaprolactone (PCL) powders were prepared from PCL pellets using a rotation mechanical mixer. PCL powders were separated by sieves with 60 and 120 meshes into four classes; 0–125 μm, 125–250 μm, 0–250 μm and 250–500 μm. Biodegradation tests of PCL powders and cellulose powders in an aqueous solution at 25°C were performed using the coulometer according to ISO 14851. Biodegradation tests of PCL powders and cellulose powders in controlled compost at 58°C were performed by the Mitsui Chemical Analysis and Consulting Service, Inc. according to ISO 14855-1 and by using the Microbial Oxidative Degradation Analyzer (MODA) instrument according to ISO/DIS 14855-2. PCL powders were faster biodegraded than cellulose powders. The reproducibility of biodegradation of PCL powders is excellent. Differences in the biodegradation of PCL powders with different class were not observed by the ISO 14851 and ISO/DIS 14855-2. An enzymatic degradation test of PCL powders with different class was studied using an enzyme of Amano Lipase PS. PCL with smaller particle size was faster degraded by the enzyme. PCL powders with regulated sizes from 125 μm to 250 μm are proposed as a reference material for the biodegradation test.  相似文献   
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996.
Over recent decades, public participation in technology assessment has spread internationally as an attempt to overcome or prevent societal conflicts over controversial technologies. One outcome of this new surge in public consultation initiatives has been the increased use of participatory consensus conferences in a number of countries. Existing evaluations of consensus conferences tend to focus on the modes of organization, as well as the outcomes, both procedural and substantial, of the conferences they examine. Such evaluations seem to rest on the assumption that this type of procedure has universally agreed goals and meanings, and that therefore consensus conferences can readily be interpreted and applied across national boundaries. This article challenges this approach to consensus conferences. The core of the article is a study of national differences in ideas about what constitutes legitimate goals for participatory arrangements. The study looks at three consensus conferences on GMOs, which took place in France, Norway, and Denmark. Drawing on this study, the article discusses the ways in which interpretations of the concept of participation; the value attributed to lay knowledge vs. technical expertise; as well as ideas about the role of the layperson, are all questions that prompt entirely different answers from country to country. Further, the article analyses these national differences within a theoretical framework of notions of democratic legitimacy.  相似文献   
997.
Multimetric indices based on fish and benthic macroinvertebrate assemblages are commonly used to assess the biological integrity of aquatic ecosystems. However, their response to specific stressors is rarely known. We quantified the response of a fish-based index (Mid-Atlantic Highlands Index of Biotic Integrity, MAH-IBI) and a benthic invertebrate-based index (West Virginia Stream Condition Index, WV-SCI) to acid mine drainage (AMD)-related stressors in 46 stream sites within the Cheat River watershed, West Virginia. We also identified specific stressor concentrations at which biological impairment was always or never observed. Water chemistry was extremely variable among tributaries of the Cheat River, and the WV-SCI was highly responsive across a range of AMD stressor levels. Furthermore, impairment to macroinvertebrate communities was observed at relatively low stressor concentrations, especially when compared to state water quality standards. In contrast to the WV-SCI, we found that the MAH-IBI was significantly less responsive to local water quality conditions. Low fish diversity was observed in several streams that possessed relatively good water quality. This pattern was especially pronounced in highly degraded subwatersheds, suggesting that regional conditions may have a strong influence on fish assemblages in this system. Our results indicate that biomonitoring programs in mined watersheds should include both benthic invertebrates, which are consistent indicators of local conditions, and fishes, which may be indicators of regional conditions. In addition, remediation programs must address the full suite of chemical constituents in AMD and focus on improving linkages among streams within drainage networks to ensure recovery of invertebrate and fish assemblages. Future research should identify the precise chemical conditions necessary to maintain biological integrity in mined Appalachian watersheds.  相似文献   
998.
Run-off containing increased concentrations of sediment, nutrients, and pesticides from land-based anthropogenic activities is a significant influence on water quality and the ecologic conditions of nearshore areas of the Great Barrier Reef World Heritage Area, Australia. The potential and actual impacts of increased pollutant concentrations range from bioaccumulation of contaminants and decreased photosynthetic capacity to major shifts in community structure and health of mangrove, coral reef, and seagrass ecosystems. A detailed conceptual model underpins and illustrates the links between the main anthropogenic pressures or threats (dry-land cattle grazing and intensive sugar cane cropping) and the production of key contaminants or stressors of Great Barrier Reef water quality. The conceptual model also includes longer-term threats to Great Barrier Reef water quality and ecosystem health, such as global climate change, that will potentially confound direct model interrelationships. The model recognises that system-specific attributes, such as monsoonal wind direction, rainfall intensity, and flood plume residence times, will act as system filters to modify the effects of any water-quality system stressor. The model also summarises key ecosystem responses in ecosystem health that can be monitored through indicators at catchment, riverine, and marine scales. Selected indicators include riverine and marine water quality, inshore coral reef and seagrass status, and biota pollutant burdens. These indicators have been adopted as components of a long-term monitoring program to enable assessment of the effectiveness of change in catchment-management practices in improving Great Barrier Reef (and adjacent catchment) water quality under the Queensland and Australian Governments’ Reef Water Quality Protection Plan.  相似文献   
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1000.
Mining of Cu took place in Kvalsund in the Arctic part of Norway in the 1970s, and mine tailings were discharged to the inner part of the fjord, Repparfjorden. Metal speciation analysis was used to assess the historical dispersion of metals as well as their potential bioavailability from the area of the mine tailing disposal. It was revealed that the dispersion of Ba, Cr, Ni, Pb and Zn from the mine tailings has been limited. Dispersion of Cu to the outer fjord has, however, occurred; the amounts released and dispersed from the mine tailing disposal area quantified to be 2.5–10 t, less than 5% of Cu in the original mine tailings. An estimated 80–390 t of Cu still remains in the disposal area from the surface to a depth of 16 cm. Metal partitioning showed that 56–95% of the Cu is bound in the potential bioavailable fractions (exchangeable, reducible and oxidisable) of the sediments, totalling approximately 70–340 t, with potential for continuous release to the pore water and re-precipitation in over- and underlying sediments. Surface sediments in the deposit area were affected by elevated Cu concentrations just above the probable effect level according to the Norwegian sediment quality criteria, with 50–80% Cu bound in the exchangeable, reducible and oxidisable fractions, potentially available for release to the water column and/or for uptake in benthic organisms.  相似文献   
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