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Since 1995, the Institute for Environment and Development in Portugal has obtained >300 stack samples from various point sources of Portuguese industries. A coherent database was made with the collected results. The limit values fixed by several European legal documents consulted, Portuguese, Spanish, French, Italian, and Dutch emission legislation, were applied to the Institute for Environment and Development stack sampling inventory (from 1995 to 2000) to evaluate the efficiency of these standards in promoting the control and reduction of atmospheric pollutants emissions, especially regarding nitrogen oxides, sulfur dioxide, and particulate matter. The conclusion was that the original Portuguese legislation was not restrictive enough and not very efficient regarding emissions reduction. In contrast, the Dutch and Italian legislations are quite restrictive but very efficient concerning emission control for the three pollutants analyzed. One of the outcomes of this study was the publication of a new law in Portugal regulating the emissions of atmospheric pollutants. The strategy of this emissions control law follows the conclusions found in this study including the concept of a mass flow threshold and different approaches depending on source dimension.  相似文献   
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The implementation of sustainable development requires several support instruments. One of the major instruments in the Rio Declaration to support this process has been environmental assessment that has been given considerable emphasis as to its potential ability to help achieve more sustainable forms of development. Regional environmental assessment (REA) has shown to be effective in supporting local sustainable development process. Selected environmental assessment methods have been␣used to improve the REA exercise and provide reliable data for decision-making not only to correct environmental problems due to past unsustainable social-economic developments but also help local governments to implement Agenda 21 (AG21) plans and projects.  相似文献   
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Although changes in depth to groundwater occur naturally, anthropogenic alterations may exacerbate these fluctuations and, thus, affect vegetation reliant on groundwater. These effects include changes in physiology, structure, and community dynamics, particularly in arid regions where groundwater can be an important water source for many plants. To properly manage ecosystems subject to changes in depth to groundwater, plant responses to both rising and falling groundwater tables must be understood. However, most research has focused exclusively on riparian ecosystems, ignoring regions where groundwater is available to a wider range of species. Here, we review responses of riparian and other species to changes in groundwater levels in arid environments. Although decreasing water tables often result in plant water stress and reduced live biomass, the converse is not necessarily true for rising water tables. Initially, rising water tables kill flooded roots because most species cannot tolerate the associated low oxygen levels. Thus, flooded plants can also experience water stress. Ultimately, individual species responses to either scenario depend on drought and flooding tolerance and the change in root system size and water uptake capacity. However, additional environmental and biological factors can play important roles in the severity of vegetation response to altered groundwater tables. Using the reviewed information, we created two conceptual models to highlight vegetation dynamics in areas with groundwater fluctuations. These models use flow charts to identify key vegetation and ecosystem properties and their responses to changes in groundwater tables to predict community responses. We then incorporated key concepts from these models into EDYS, a comprehensive ecosystem model, to highlight the potential complexity of predicting community change under different fluctuating groundwater scenarios. Such models provide a valuable tool for managing vegetation and groundwater use in areas where groundwater is important to both plants and humans, particularly in the context of climate change.  相似文献   
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This paper expands on air travel accident research by examining the relationship between air travel accidents and airline traffic or volume in the period from 1927–2006. The theoretical model is based on a representative airline company that aims to maximise its profits, and it utilises a fractional integration approach in order to determine whether there is a persistent pattern over time with respect to air accidents and air traffic. Furthermore, the paper analyses how airline accidents are related to traffic using a fractional cointegration approach. It finds that airline accidents are persistent and that a (non‐stationary) fractional cointegration relationship exists between total airline accidents and airline passengers, airline miles and airline revenues, with shocks that affect the long‐run equilibrium disappearing in the very long term. Moreover, this relation is negative, which might be due to the fact that air travel is becoming safer and there is greater competition in the airline industry. Policy implications are derived for countering accident events, based on competition and regulation.  相似文献   
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The Convention on Biological Diversity proposed the Aichi Biodiversity Targets to improve conservation policies and to balance economic development, social welfare, and the maintenance of biodiversity/ecosystem services. Brazil is a signatory of the Aichi Biodiversity Targets and is the most diverse country in terms of freshwater fish, but its national policies have supported the development of unsustainable commercial and ornamental aquaculture, which has led to serious disturbances to inland ecosystems and natural resources. We analyzed the development of Brazilian aquaculture to show how current aquaculture expansion conflicts with all 20 Aichi Targets. This case suggests that Brazil and many other megadiverse developing countries will not meet international conservation targets, stressing the need for new strategies, such as the environmental management system, to improve biodiversity conservation.  相似文献   
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Environmental Science and Pollution Research - The removal of Cr3+ from water solutions by biosorbents from the rind, endosperm, and endosperm + episperm of the Jatropha curcas was evaluated....  相似文献   
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This article presents and discusses SO(2) (ppbv) concentration measurements combined with meteorological data (mainly wind speed and direction) for a five-year campaign (1996 to 2000), in a site near an oil refinery plant close to the city of La Plata and surroundings (aprox. 740.000 inh.), considered one of the six most affected cities by air pollution in the country. Since there is no monitoring network in the area, the obtained results should be considered as medium term accumulated data that enables to determine trends by analyzing together gas concentrations and meteorological parameters. Preliminary characterization of the behaviour of the predominant winds of the region in relation with potential atmospheric gas pollutants from seasonal wind roses is possible to carry out from the data. These results are complemented with monthly averaged SO(2) measurements. In particular, for year 2000, pollutant roses were determined which enable predictions about contamination emission sources. As a general result we can state that there is a clear increase in annual SO(2) concentration and that the selected site should be considered as a key site for future survey monitoring network deployment. Annual SO(2) average concentration and prevailing seasonal winds determined in this work, together with the potential health impact of SO(2) reveals the need for a comprehensive and systematic study involving particulate matter an other basic pollutant gases.  相似文献   
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