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61.
The paper reviews the current state of knowledge regarding sources of mercury emission in Poland. Due to the large quantities of coal burned at present, as well as taking into account existing reserves, coal remains the main energy source of energy in Poland. The data on coal consumption in Poland in the past, at present and in the future are discussed in the paper. Information on the content of mercury in Polish coals is presented.Coal combustion processes for electricity and heat production are the main source of anthropogenic mercury emission in Poland. It is expected that the current emissions will decrease in the future due to implementation of efficient control measures. These measures for emission reduction are described in the paper. Results of estimated mercury emission from coal-fired power station situated in the Upper Silesia Region, Poland are investigated. A relationship between mercury emission to the air and the mercury content in the consumed coal in power station equipped with the electrostatic precipitators (ESPs) is discussed.  相似文献   
62.
63.
The main objective of this paper is to design and test a decentralized exchange mechanism that generates the location-specific pricing necessary to achieve efficient allocations in the presence of instream flow values. Although a market-oriented approach has the potential to improve upon traditional command and control regulations, questions remain about how these rights-based institutions can be implemented such that the potential gains from liberalized trade can be realized. This article uses laboratory experiments to test three different water market institutions designed to incorporate instream flow values into the allocation mechanism through active participation of an environmental trader. The smart, computer-coordinated market described herein offers the potential to significantly reduce coordination problems and transaction costs associated with finding mutually beneficial trades that satisfy environmental constraints. We find that direct environmental participation in the market can achieve highly efficient and stable outcomes, although the potential does exist for the environmental agent to influence outcomes.  相似文献   
64.
应用环境库兹涅茨曲线的基本模型对北京市和房山区1995-2003年的环境污染与经济增长进行了实证分析。研究表明,北京市和房山区大多数环境质量和污染排放强度的指标已越过转折点,进入环境质量逐步改善的阶段,北京市和房山区越过转折点的经济水平明显低于发达国家。  相似文献   
65.
Accurate and complete information on the emissions of persistent organic pollutants (POPs) are essential for interpreting historical, current and future contamination levels in remote areas. However, this information is also crucial for decision makers aiming at further reduction of the environmental loading of these substances on a regional scale. In this study, we identify and discuss specific POP emission inventory features that are deemed essential to understand, predict and control the behaviour of such substances on a European scale. It is shown that the scientific value of official emission data is limited (e.g. for deriving source–receptor relationships on a European scale), as there is insufficient information on spatial, temporal and compound coverage. Likewise, we argue that non-official emission data (i.e. research-driven emission inventories), which are based on aggregated statistics, may be of limited value for the identification of further emission control strategies. It is thus argued that future emission inventories should be developed in a format that is suitable to serve both policy- and research-oriented applications. Further improvement of official emission data with respect to research-driven features seems to be the most sensible way to proceed. Finally, the empirical basis of current emission inventories remains weak, and further research on emission identification and characterisation seem needed (a) to gain confidence in predicted source–receptor relationship as well as (b) for the development of sound control strategies.  相似文献   
66.
Cattle overwintering areas common in central Europe may represent significant point sources of the important greenhouse gases, nitrous oxide (N2O) and carbon dioxide (CO2). A 2-year field study was carried out in order to estimate the emissions of N2O and CO2 from soil in a cattle overwintering area located in the southwest of the Czech Republic. The measurements were performed at three sampling locations along a gradient of animal impact (severe, moderate, slight) to test the hypothesis that emissions of CO2 and N2O are positively related to the degree of impact. In addition to CO2 and N2O fluxes determined by using non-vented manual closed chambers, soil mineral nitrogen (NH4+ and NO3), pH and temperature were determined to assess their regulatory role and impact on gas fluxes. The overwintering area was about 4 ha and it had been used for overwintering of about 90 cows since 1995. Deposition of animal excreta resulted in a significant accumulation of nitrogen in the soil during winter, but most of the N2O was emitted during a few short periods in spring and/or in late autumn. Maximum N2O fluxes of up to 2.5 mg N2O-N m−2 h−1 were recorded at the most impacted location near the animal house, where the highest concentrations of soil mineral nitrogen also occurred. The emissions of CO2 showed a completely different pattern to those of N2O, being correlated with soil temperature; the highest emissions thus occurred in June–July, while very low fluxes were found in winter. Emission values ranged from about 0 to 700 mg C-CO2 m−2 h−1. Furthermore, the effect of animal impact on CO2 emissions was opposite to that on N2O fluxes, as the highest CO2 fluxes were mostly recorded at the least impacted location, where respiration of plants most likely increased overall CO2 production. The results show that cattle overwintering areas are important sources of greenhouse gases, including N2O and CO2. Fluxes of these two gases are, however, differently distributed over the year, which also suggests that they are controlled by different environmental and soil factors.  相似文献   
67.
The effect of synthetic and mineral oils on the formation of polyaromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) in emissions from a spark ignition engine was studied on a Skoda Favorit engine fueled with leaded gasoline. The test cycle simulated urban traffic conditions on a chassis dynamometer, in accordance with the ECC 83.00 test. The data for selected PAHs as well as PCDDs, PCDFs, and PCBs congener profiles are presented. PCDD/Fs emissions for an unused oil and the oil after 10000-km operation varied from 300 to 2000 fmol/m3, PCBs emissions from 75 to 178 pmol/m3, and PAHs emissions from 150 to 420 microg/m3. The content of PCBs in oils varied from 2 to 920 mg/kg.  相似文献   
68.
The influence of in-port ship emissions on gases and PM_(10) concentrations has been estimated in the port city of Calais, northern France, one of the busiest harbor in Europe,with numerous rotations of ferries or roll-on/roll-off cargo in average per day. NO_x, SO_2, O_3 and PM_(10) concentrations were continuously measured over a three-month period, as well as real-time particle size distribution. A rural site located at Cape Gris-Nez, 20km from Calais, was considered to deduce intrinsic contribution of ship emissions at the harbor city.The average concentrations of the studied species as well as the pattern of the conditional bivariate probability function at the two sites evidenced that in-port shipping, especially during the maneuvering operations, has an important influence on the NO_xand SO_2 concentrations. The impact of shipping in the harbor of Calais on average concentrations was estimated to 51% for SO_2, 35% for NO, 15% for NO_2 and 2% for PM_(10) in the studied period.Concentration peaks of SO_2 and NO_x associated with an O_3 depletion appeared synchronized with departures and arrivals of ferries. For winds blowing from the harbor,when compared to the background level, the number of particles appeared 10 times higher,with the highest differences in the 30–67nm and the 109–167 nm size ranges. The average impact of in-port ships on PM310 concentrations was estimated to + 28.9 μg/mand concerned mainly the PM1 size fraction(40%). Punctually, PM_(10) can potentially reach a concentration value close to 100 μg/m~3.  相似文献   
69.
Mediterranean wetlands are of key interest in the preservation of biodiversity. However, their ecological water requirement is in constant competition with human uses, particularly in a context of aridity and climate change. This paper examines the case of the Ichkeul Lake‐Lagoon system located in the north of Tunisia in a river basin that is heavily contributing to the water supply of southern regions through water transfers. It maps out the various actors involved, their stakes, discourses and strategies, and explains the current degradation of the Ichkeul system by unpacking the decision‐making power of these actors. It confirms that marginal social groups, ecosystems and next generations are the main parties affected by current water allocation patterns.  相似文献   
70.
Emissions of volatile organic compounds (VOCs) from the compost maturation building in a municipal solid waste treatment facility were inventoried by solid phase microextraction and gas chromatography–mass spectrometry. A large diversity of chemical classes and compounds were found. The highest concentrations were found for n-butanol, methyl ethyl ketone and limonene (ppmv level). Also, a range of compounds exceeded their odor threshold evidencing that treatment was needed. Performance of a chemical scrubber followed by two parallel biofilters packed with an advanced packing material and treating an average airflow of 99,300 m3 h?1 was assessed in the treatment of the VOCs inventoried. Performance of the odor abatement system was evaluated in terms of removal efficiency by comparing inlet and outlet abundances. Outlet concentrations of selected VOCs permitted to identify critical odorants emitted to the atmosphere. In particular, limonene was found as the most critical VOC in the present study. Only six compounds from the odorant group were removed with efficiencies higher than 90%. Low removal efficiencies were found for most of the compounds present in the emission showing a significant relation with their chemical properties (functionality and solubility) and operational parameters (temperature, pH and inlet concentration). Interestingly, benzaldehyde and benzyl alcohol were found to be produced in the treatment system.  相似文献   
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