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401.
Since the United Nations Conference on Environment and Development in 1992 in Rio de Janeiro, sustainable development became an important issue. Sustainable development often focuses on a single sector or parameter such as tourism, energy supply, water management, different aspects of nature conservation, or economy. In this paper, we provide a comprehensive picture of the development of a region since the Middle Ages and discuss whether this development can be evaluated as socially, economically and ecologically sustainable. We carried out a combined qualitative–quantitative assessment where we use quantitative data and indicators when available, as well as literature sources and expert knowledge from the region for a qualitative assessment. We judge that generally a sustainable development in the Allgäu region can be found, although also some critical points and contentious issues exist. An overall good economic and income situation for most people, the good ecological conditions and rich biodiversity, the relatively well-established social structure, as well as the identity of the people with the region and comparatively low social discrepancy, can be positively stated. In contrast, different actual and future threats exist such as new or planned infrastructure, increasing traffic or tourism activities in certain areas that degrade habitats and reduce species richness, intensification of agriculture in certain areas, but also abandonment of agriculture in other areas, loss of traditions and customs, and declining numbers of smallholders. The objective for the region would be to minimise these negative impacts and reinforce positive trends to assure the sustainable development of the Allgäu.  相似文献   
402.
Megacities are not only important drivers for socio-economic development but also sources of environmental challenges. Many megacities and large urban agglomerations are located in the coastal zone where land, atmosphere, and ocean meet, posing multiple environmental challenges which we consider here. The atmospheric flow around megacities is complicated by urban heat island effects and topographic flows and sea breezes and influences air pollution and human health. The outflow of polluted air over the ocean perturbs biogeochemical processes. Contaminant inputs can damage downstream coastal zone ecosystem function and resources including fisheries, induce harmful algal blooms and feedback to the atmosphere via marine emissions. The scale of influence of megacities in the coastal zone is hundreds to thousands of kilometers in the atmosphere and tens to hundreds of kilometers in the ocean. We list research needs to further our understanding of coastal megacities with the ultimate aim to improve their environmental management.  相似文献   
403.
This article reviews interactions and health impacts of physical, chemical, and biological weather. Interactions and synergistic effects between the three types of weather call for integrated assessment, forecasting, and communication of air quality. Today’s air quality legislation falls short of addressing air quality degradation by biological weather, despite increasing evidence for the feasibility of both mitigation and adaptation policy options. In comparison with the existing capabilities for physical and chemical weather, the monitoring of biological weather is lacking stable operational agreements and resources. Furthermore, integrated effects of physical, chemical, and biological weather suggest a critical review of air quality management practices. Additional research is required to improve the coupled modeling of physical, chemical, and biological weather as well as the assessment and communication of integrated air quality. Findings from several recent COST Actions underline the importance of an increased dialog between scientists from the fields of meteorology, air quality, aerobiology, health, and policy makers.  相似文献   
404.
405.
ABSTRACT

Based on requirements under the Clean Air Act Amendments of 1990, most state vehicle inspection and maintenance (I/M) programs have, since 2002, replaced the tailpipe emission testing with the on-board diagnostic (OBD) II testing for 1996 model and newer vehicles. This test relies on the OBD II system to give the pass or fail result, depending on certain conditions that might cause the vehicle to emit pollution 1.5 times higher than the regulated standard. The OBD II system is a computer and sensors installed in the vehicle to monitor the emission control units and signal if there is any malfunction. As a vehicle ages, its engine, pollution control units, and OBD II system deteriorate. Because the OBD II system's durability directly influences the test outcome, it is important to examine the fleetwide trend in the OBD II test results in comparison with an alternative measure of identifying high emitting vehicles. This study investigates whether the validity and reliability of the OBD II test is related to the age of the OBD II system installed in the fleet. Using Atlanta's I/M testing records and remote sensing device (RSD) data collected during 2002–2005, this research establishes the convergent validity and interobserver reliability criteria for the OBD II test based on on-road emissions measured by RSDs. The study results show that older vehicles exhibit significantly lower RSD–OBD II outcome agreement than newer vehicles. This suggests that the validity and reliability of the OBD II test may decline in the older vehicle fleets. Explanations and possible confounding factors for these findings are discussed.

IMPLICATIONS This research demonstrates the potential worsening validity and reliability of the on-board diagnostic (OBD) II test in old vehicles. If the main source of low validity and reliability comes from the OBD II system malfunction, we expect this malfunctioning OBD II fleet will continue to grow in the future. If unchecked, the deterioration of OBD II system may impair the effort of the inspection and maintenance (I/M) program to identify high-emitting vehicles and the ultimate objective of reducing the air pollution from automobiles. This result is especially important in a regulatory context where technological and emissions standards dominate environmental policy and yet little attention is paid to the possible degradation of environmental monitors themselves.  相似文献   
406.
Internationally petroleum contamination is widespread, posing serious environmental risks including surface and groundwater contamination, thus remediation is essential. The implementation of remediation options is becoming more complex with the increasing influence of stakeholders on the outcome of decision-making processes. Acceptance of remediation schemes during implementation can be increased by involving stakeholders and the public in the decision-making stage. In petroleum remediation involving multiple stakeholders, Multicriteria Analysis has been employed due to its ability to incorporate the preferences of each stakeholder through weighting. The research focused on investigating ways to improve the weighting process. The study demonstrated the utility of SWING, and determined which type of participant and how many participants to include in the decision process, through the application of ELECTRE III and Weighted Summation. It was recommended that a mixture of stakeholders, the public and experts be involved. The total number of participants will be limited by the choice of participatory and weighting methods. The careful selection of participants, as well as the choice of participatory and weighting methods, can minimize the subjectivity involved in MCA weighting, thereby lending decisions in petroleum remediation greater legitimacy.  相似文献   
407.
This paper evaluates the results of contamination of residents and residential homes located in close proximity to a Wood Treatment Plant. The plant has produced treated wood products continuously since 1904. The principle chemicals used to treat the wood, which is primarily used for railroad ties (oblong objects laid perpendicular to the rails to act as a base for the tracks), are creosote and pentachlorophenol. For a number of years, the plant burned treated waste wood products containing creosote and pentachlorophenol. First the plant pressure impregnates the wood with creosote and pentachlorophenol, and then the wood is stacked on open ground to allow it to air dry. Chemicals from recently treated wood ties are allowed to evaporate into the air or drip onto the ground surrounding the stacked wood. Small drainage ditches carry the liquid wastes into larger water channels where eventually the waste streams are discharged into a river adjacent to the plant. The river serves as a source of drinking water for the nearby community. Prevailing wind patterns favor a drift of air emissions from the plant's boiler stack over the nearby community and its residents. Over the past few years, the town's residents have become increasingly concerned about their health status and have voiced concerns regarding multiple health problems (including cancer), possibly associated with plant discharges. The intention of this study is to examine a representative sample of the potentially affected residents and to evaluate their residential environment for the presence of dioxin and/or its congeners. Data obtained from EPA's Toxic Release Information (TRI) database revealed the plant routinely discharged creosote, pentachlorophenol, dioxin and dioxin-like compounds into the ambient air via fugitive air emissions and surface waste waters. Sampling of household dust and water sediment within and outside of residences within a 2-mile radius of the plant revealed the presence of significantly elevated levels of dioxins, principally octachlorodibenzo-p-dioxin (OCDD) and 1,2,3,4,6,7,8-hepta-CDD. Biomonitoring of 29 subjects identified the presence of significantly elevated chlorinated dioxins and furan levels (OCDD=1049 ppt for exposed and 374 ppt for controls and 1,2,3,4,6,7,8-hepta CDD=132 ppt for exposed and 45.1 ppt for controls). These levels are consistent with exposures to pentachlorophenol in this group of subjects. And they confirm the presence of unsafe levels of chlorinated dioxins in these persons.  相似文献   
408.
Subaquatic sediment samples derived form Elbe and Mulde Rivers, Germany, were analyzed for extractable and non-extractable anthropogenic organic compounds by a non-target screening approach. Applied methodologies were gas chromatography-mass spectrometry, dispersion extraction and degradation procedures, particularly alkaline and acidic hydrolysis, boron tribromide treatment, ruthenium tetroxide oxidation as well as pyrolysis and TMAH (tetramethylammonium hydroxide)-thermochemolysis. Numerous compounds were identified, including halogenated benzenes, anisoles, styrenes, alkanes, diphenylmethane derivates, anilines, phenols and diphenyl ethers. The results were interpreted with respect to compound specific modes of incorporation as well as to potential sources (e.g. municipal, agricultural, industrial). Extractable and non-extractable fractions differed significantly with respect to their qualitative and quantitative composition. For example, quantities in the extractable and non-extractable fractions of chlorinated benzenes differed up to factor 50. Among other significant results, the investigation revealed hints for a dependence of the mode of incorporation of chlorinated benzenes on their substitution pattern.  相似文献   
409.
In the San Bernardino Mountains of southern California, ozone (O(3)) concentrations have been elevated since the 1950s with peaks reaching 600ppb and summer seasonal averages >100ppb in the 1970s. During that period increased mortality of ponderosa and Jeffrey pines occurred. Between the late 1970s and late1990s, O(3) concentrations decreased with peaks approximately 180ppb and approximately 60ppb seasonal averages. However, since the late 1990s concentrations have not changed. Monitoring during summers of 2002-2006 showed that O(3) concentrations (2-week averages) for individual years were much higher in western sites (58-69ppb) than eastern sites (44-50ppb). Potential O(3) phytotoxicity measured as various exposure indices was very high, reaching SUM00 - 173.5ppmh, SUM60 - 112.7ppmh, W126 - 98.3ppmh, and AOT40 - 75ppmh, representing the highest values reported for mountain areas in North America and Europe.  相似文献   
410.
Stable isotopes of carbon (δ13C) and nitrogen (δ15N) are used frequently in ecotoxicological investigations of birds to relate contaminant levels to trophic position (δ15N) or foraging location (δ13C) and many researchers using avian feathers in such investigations use δ13C or δ15N as a predictor of contaminant concentrations. Contaminants, especially mercury, however, are integrated into feathers over different time periods than are stable isotopes, resulting in spurious relationships that have no biological meaning. I show the fundamental principles behind the conclusion that relating δ13C or δ15N to contaminant concentrations in feathers is not appropriate in light of the number of recent studies that have employed this approach, and make recommendations for those wishing to investigate the relationship between contaminants and stable isotope ratios.  相似文献   
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