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Global freshwater resources are being increasingly polluted and depleted, threatening sustainable development and human and ecosystem health. Utilizing case studies from 4 different watersheds in the United States, Japan, Switzerland, and Brazil, this paper identifies the most relevant sustainability deficits and derives general vectors for more sustainable water management. As a consequence of the demographic and economic developments experienced in the last few decades, each watershed has suffered declines in water quality, streamflow and biotic resources. However, the extent and the cultural perception of these water-related problems vary substantially in the different watersheds, leading to specific water-management strategies. In industrialized countries, exemplified by the US, Switzerland, and Japan, these strategies have primarily consisted of finance- and energy-intensive technologies, allowing these countries to meet water requirements while minimizing human health risks. But, from a sustainability point of view, such strategies, relying on limited natural resources, are not long-term solutions. For newly industrialized countries such as Brazil, expensive technologies for water management are often not economically feasible, thus limiting the extent to which newly industrialized and developing countries can utilize the expertise offered by the industrialized world. Sustainable water management has to be achieved by a common learning process involving industrialized, newly industrialized, and developing countries, following general sustainability guidelines as exemplified in this paper.  相似文献   

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The mixing ratios of HCFC-141b (1,1-dichlorofluoroethane) and HCFC-142b (1-chloro-1,1-difluoroethane) have been rising steadily in baseline air at Mace Head, Ireland over the 10-year period from 1994 to 2004. These HCFCs are widely used replacements for the chlorofluorocarbons phased out under the Montreal Protocol and its subsequent amendments. Analysis of the HCFC content of regionally-polluted air arriving at Mace Head from the European continent shows that European emissions reached a peak during 2000–2001 and have declined subsequently, following the phase-out in their usage. European emissions of HCFC-141b have been further constrained by observations at the High-Alpine Jungfraujoch site. The reductions are consistent with the phase-out of HCFC production and use from the year 2001 onwards mandated by European regulations designed to exceed the requirements of the Montreal Protocol.  相似文献   

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This paper frames the problem of implementing 'the polluter pays' in the European Union as a social-political process in which conflicts emerge and must be resolved between competing interests, between people holding different value systems and different principles of judgement, and also between different representations of future states and different visions of the world. 'The polluter pays' is a principle for internalising external costs and assigning liability. Its application may seem to entail a need for monetary valuation of damages. This allows environmental impacts and protection questions to be formulated as optimal resource use problems through the extension of traditional cost-benefit analysis techniques. However, reasons such as uncertainty, distributional concerns, and diversity of ethical positions make monetary valuation difficult or inappropriate. Decision support techniques are then sought that do not depend exclusively on monetisation, such as multicriteria and deliberative methods. The process of 'internalisation' of environmental damages is thus expressed through broad societal adjustments. Procedures need to be found that are socially legitimate and effective in the sense that the stakeholders can accept it as dealing adequately with their concerns. This is a collective 'internalisation': we are all polluters; we all pay – shouldering the clean up burdens, the institutional adjustments, the worries and the risks – in more or less unequal shares. The burden distribution will inevitably be a matter of controversy.  相似文献   

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Flooding patterns of the Okavango Wetland in Botswana between 1972 and 2000   总被引:1,自引:0,他引:1  
The inundated area of the Okavango Delta changes annually and interannually. The variability relates to regional precipitation over the catchment area in the Angolan highlands, and to local rainfall. The patterns of the wetland were captured using more than 3000 satellite images for the period 1972 to 2000, near daily NOAA AVHRR data for 1985-2000, and less frequent images of the Landsat sensors from 1972 onwards. One AVHRR image for every 10-day period was classified into land and water using an unsupervised classification method. Evaluation against Landsat TM and ERS2-ATSR data indicate an agreement of 89% for the size of estimated inundation area. Results show that the wetland area has varied between approximately 2450 km2 and 11400 km2 during the last 30 years.  相似文献   

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Concentrations of traffic-related air pollution can be highly variable at the local scale and can have substantial seasonal variability. This study was designed to provide estimates of intra-urban concentrations of ambient nitrogen dioxide (NO2) in Montreal, Canada, that would be used subsequently in health studies of chronic diseases and long-term exposures to traffic-related air pollution. We measured concentrations of NO2 at 133 locations in Montreal with passive diffusion samplers in three seasons during 2005 and 2006. We then used land use regression, a proven statistical prediction method for describing spatial patterns of air pollution, to develop separate estimates of spatial variability across the city by regressing NO2 against available land-use variables in each of these three periods. We also developed a “pooled” model across these sampling periods to provide an estimate of an annual average. Our modelling strategy was to develop a predictive model that maximized the model R2. This strategy is different from other strategies whose goal is to identify causal relationships between predictors and concentrations of NO2.Observed concentrations of NO2 ranged from 2.6 ppb to 31.5 ppb, with mean values of 12.6 ppb in December 2005, 14.0 ppb in May 2006, and 8.9 ppb in August 2006. The greatest variability was observed during May. Concentrations of NO2 were highest downtown and near major highways, and they were lowest in the western part of the city. Our pooled model explained approximately 80% of the variability in concentrations of NO2. Although there were differences in concentrations of NO2 between the three sampling periods, we found that the spatial variability did not vary significantly across the three sampling periods and that the pooled model was representative of mean annual spatial patterns.  相似文献   

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Biomass burning, in the form of savanna fires and firewood for cooking and warmth, is widespread during the dry winter months in Southern Africa. This study was carried out to investigate its impact on the environment in Gaborone, Botswana, which is a small-sized city with very little pollution from industrial sources. Measurements of aerosol size and number concentrations were carried out at the University of Botswana campus in Gaborone from September 1999 to July 2000 using two automatic laser scattering particle counters. Particles were monitored in eight size ranges from 0.1 to 5.0 μm. The mean daily particle concentrations were found to vary from about 200 cm−3 on clear visibility days during the summer to a high of over 9000 cm−3 on cold winter evenings, when there was a significant smoke haze over the city. Particle concentrations were noticeably higher during the winter than in the summer. During a typical winter day, the total particle concentration peaked between 18 and 23 h, often showing an increase of over four-fold from mid-morning minimum values. The aerosol number size distributions under various conditions were investigated and the corresponding surface area and volume distributions were derived. In general, both the surface and volume distributions were bimodal with peaks close to 0.2 μm and at 5.0 μm or greater. A hand-held counter with a minimum detectable particle size of 0.3 μm was used to monitor the size and number concentrations of aerosols across the city. The results indicate a consistent pattern of maximum concentration in the highly populated areas close to the city centre, falling significantly in the sparsely populated outlying areas by up to an order of magnitude during peak biomass burning, suggesting that much of the smoke particles in the city are removed by wind.  相似文献   

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Air pollution is one of the most crucial current environmental problems, especially in urban areas. To confront air pollution, the European Union has implemented several policies and programmes. Among these, the Auto-oil Programme is a cost-effective framework which involves all relevant actors (car-makers, oil industries, governments, local authorities, etc.) in concerted action. Athens faces a severe air pollution problem. In this respect, Auto-oil seems to offer a promising chance for Athens to improve its atmosphere. The present paper examines the effectiveness of the Auto-oil Programme to relieve air pollution in Athens. Several additional measures are proposed whenever it seems to be necessary.  相似文献   

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Absorption of sunlight by sub-micron particles is an important factor in calculations of the radiation balance of the earth and thus in climate modelling. Carbon-containing particles are generally considered as the most important in this respect. Major sources of these particles are generally considered to be bio-mass burning and vehicle exhaust. In order to characterise size fractionated particulate matter in a rural village in Botswana with respect to light absorption and elemental content experiments were performed, in which simultaneous sampling was made with a dichotomous impactor and a laboratory-made sampler, made compatible with black carbon analysis by reflectometry. The dichotomous impactor was equipped with Teflon filters and the other sampler with glass fibre filters. Energy dispersive X-ray fluorescence was used for elemental analysis of both kinds of filters. It appeared that Teflon filters were the most suitable for the combination of mass-, elemental- and black carbon measurements. The black carbon content in coarse (2.5–10 μm) and fine (<2.5 μm) particles was determined separately and related to elemental content and emission source. The results show that the fine particle fraction in the aerosol has a much higher contribution of black particles than the coarse particle fraction. This observation is valid for the village in Botswana as well as for a typical industrialised city in Sweden, used as a reference location.  相似文献   

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Environmental Science and Pollution Research - China’s extraordinary economic development has provided the country’s growing population with easier access to animal food products,...  相似文献   

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The goal of this modeling study is to determine how concentrations of ozone respond to changes in climate over the eastern USA. The sensitivities of average ozone concentrations to temperature, wind speed, absolute humidity, mixing height, cloud liquid water content and optical depth, cloudy area, precipitation rate, and precipitating area extent are investigated individually. The simulation period consists of July 12–21, 2001, during which an ozone episode occurred over the Southeast. The ozone metrics used include daily maximum 8 h average O3 concentration and number of grid cells exceeding the US EPA ambient air-quality standard. The meteorological factor that had the largest impact on both ozone metrics was temperature, which increased daily maximum 8 h average O3 by 0.34 ppb K−1 on average over the simulation domain. Absolute humidity had a smaller but appreciable effect on daily maximum 8 h average O3 (−0.025 ppb for each percent increase in absolute humidity). While domain-average responses to changes in wind speed, mixing height, cloud liquid water content, and optical depth were rather small, these factors did have appreciable local effects in many areas. Temperature also had the largest effect on air-quality standard exceedances; a 2.5 K temperature increase led to a 30% increase in the area exceeding the EPA standard. Wind speed and mixing height also had appreciable effects on ozone air-quality standard exceedances.  相似文献   

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We surveyed four different river systems in the Greater Montreal region, upstream and downstream of entry points of contamination, from April 2007 to January 2009. The studied compounds belong to three different groups: PPCPs (caffeine, carbamazepine, naproxen, gemfibrozil, and trimethoprim), hormones (progesterone, estrone, and estradiol), and triazine herbicides and their metabolites (atrazine, deethylatrazine, deisopropylatrazine, simazine, and cyanazine). In the system A, B, and C having low flow rate and high TOC, we observed the highest detection frequencies and mass flows of PPCPs compared to the other compounds, reflecting discharge of urban contaminations through WWTPs and CSOs. However, in River D, having high flow rate and low TOC, comparable frequency of detection of triazine and their by-products and PPCPs, reflecting cumulative loads of these compounds from the Great Lakes as well as persistency against natural attenuation processes. Considering large differences in the removal efficiencies of caffeine and carbamazepine, a high ratio of caffeine/carbamazepine might be an indicative of a greater proportion of raw sewage versus treated wastewater in surface waters. In addition, caffeine appeared to be a promising indicator of recent urban fecal contaminations, as shown by the significant correlation with FC (R2 = 0.45), while carbamazepine is a good indicator of cumulative persistence compounds.  相似文献   

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CRS and SIT are two (210)Pb-based models widely used in the radiometric dating of recent sediments. (210)Pb chronologies should be validated using at least one independent tracer, such as (137)Cs. This paper demonstrates that simple methods based on the identification of (137)Cs fallout peaks cannot provide a definitive support for CRS and SIT chronologies. Two main arguments will support this assertion: Firstly, the (137)Cs time-marks cannot support a CRS or SIT chronology if the derived sedimentation rates cannot explain the whole (137)Cs activity profile without postulating mixing. Secondly, the support by the (137)Cs time-marks for a given CRS or SIT chronology cannot be considered as definitive if other dating models can equally explain the whole set of data, thereby producing a different chronology. Several case studies selected from the literature are used to support the present discussion.  相似文献   

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Räsänen T  Laakkonen S 《Ambio》2007,36(2-3):229-236
The Convention on the Protection of the Marine Environment of the Baltic Sea Area signed in 1974 in Helsinki is probably the most important environmental agreement consummated in the Baltic Sea region. This article is the first study that explores the history of this agreement, also known as the Helsinki Convention, by using primary archival sources. The principal sources are the archives of the Ministry for Foreign Affairs of Finland. We examine the role of Finland in the process that led to the signing of the Helsinki Convention from the perspective of international politics. The study focuses primarily on Finnish, Swedish, and Soviet state-level parties from the end of the 1960s to 1974. We show that Cold War politics affected in several ways negotiations and contents of the Helsinki Convention. We also argue that the Soviet Union used the emerging international environmental issues as a new tool of power politics.  相似文献   

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China and the European Union (EU) signed the first international circular economy (CE) agreement shortly after China issued the ‘Waste Ban’ (WB) on the import of 24 categories of solid waste. While the WB gained global attention, limited research addresses its political implications for international CE. Based on 72 expert interviews, 52 documents and participant observation, we study political WB narratives and corresponding perceptions of ‘Chinese’ and ‘European’ agency in the China-EU case. Our results show a political gridlock in China-EU CE coordination: the main narratives on the WB diverge on the very roles and rules of CE cooperation, scales of implementation, and the assessment criteria for environmentally and socially sustainable CE(s). To enable fruitful CE cooperation, we suggest three critical points for reflection and negotiation: (1) overcome ‘student–teacher’ roles rooted in linear development that run counter to CE ideas; (2) reconsider the focus on international and national waste diversion, instead of local waste prevention, that propels global waste markets sustained by increasing waste volumes; and (3) evaluate both the benefits and impediments of (new) trade relations for a CE cooperation that contributes to environmental and social sustainability.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01758-4.  相似文献   

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Environmental Science and Pollution Research - The preservation of natural resources via the management of diffuse pollution is currently considered to be a significant challenge in France....  相似文献   

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