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Purpose  

The aims of this paper were to quantify the heavy metals (HM) in the air of different sites in Rio de Janeiro (RJ) and Salvador (SA) using Tillandsia usneoides (Bromeliaceae) as a biomonitor, and to study the morphology and elemental composition of the air particulate matter (PM) retained on the Tillandsia surface.  相似文献   
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This paper presents a framework for understanding and improving public sector environmental decision making. Within the framework, four interrelated components are discussed: (1) the environmental and cultural context-understanding this context includes understanding what people consider to be environmental problems, the goals and values that they bring to environmental problems and decision processes, specialized and common knowledge about environmental problems, and the institutional settings within which problems are addressed; (2) planning and appraisal activitiesthese activities include forecasting and monitoring exercises, evaluations of past decisions, and decisions that processes ought to be launched to solve specific environmental problems; (3) decision-making modes-these include six typical ways of conducting an environmental problem-solving process, modes which, in the framework, are called emergency action, routine procedures, analysis-centred, elite corps, conflict management and collaborative learning; (4) decision actions-these include five generic steps that are undertaken, formally or intuitively, in virtually any decision-making situation: issue familiarization; criteria setting; option construction; option assessment; and reaching a decision. In the course of describing the framework, we show a decision-making process can be adapted to incorporate sustainability concerns, including fostering sustainable environmental and social systems, meeting obligations to future generations, and searching for robust and reasonable (rather than rigidly optimal) decisions. The framework also helps to illuminate intriguing questions regarding institutional responsibility, decision process complexity and paradigms for environmental decision making.  相似文献   
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A study was conducted to screen the three passes that link Lake Pontchartrain to the Gulf of Mexico via Lake Borne for the presence of EPA base-neutral (BN) priority pollutants and any other pollutants detected in significant concentration. Biota and sediment samples were collected and analytical procedures were developed for the trace analysis of BN organics in these matrices. Compounds identified include alkanes (normal, branched, cyclic), alkenes, aromatics, alkylated aromatics, polynuclear aromatic hydrocarbons and their alkylated derivatives, phthalates, ketones, furans, thiophenes, phenols, amines, nitriles, thiazoles, amides, aldehydes, alcohols, free fatty acids, fatty acid methyl and ethyl esters, phosphates, sterols. Concentrations were in the parts-per-billion range.  相似文献   
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The paper describes the results of a study of the impact of the National Energy on the trend towards increased utilization of coal and lignite in Texas with forecasts of increased coal and lignite utilization for the electric utility and industrial sectors. Environmental impacts of this increased coal and lignite use are projected in terms of increased air pollutant emissions and air quality impacts. Economic costs of compliance with alternative source emission regulations are also projected for the electric utility industry.Lignite consumption in Texas under the National Energy Plan is projected to increase from the present 13 million metric tons in 1976 to 57 million metric tons annually by 1985. Sub-bituminous coal consumption in Texas is projected to increase from 1 million metric per year in 1976 to 49 million metric tons per year in 1985. Bituminous coal consumption in Texas is expected to increase from less than one million metric tons per year in 1976 to about 3 million metric tons per year in 1985.Major increases in sulfur oxides emissions from coal and lignite combustion in Texas can be expected by 1985 of up to 1.5 × 109 kg per year without controls and 0.2 × 109 kg per year with controls. Increases in acid precipitation formation will result in north-east Texas from extensive lignite usage for electric power generation as a detriment to agriculture. The photochemical air pollution problem in the Houston area will probably worsen primarily because of increased nitrogen oxides and sulfur oxides emissions because of industrial coal combustion. Capital costs of air pollution controls in Texas for coal-fired utility boilers are estimated as up to U.S. $3.9 billion by 1985, with total operating costs of up to U.S. $1.2 billion per year.  相似文献   
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