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1.
The excess of acidic and eutrophying depositions over critical loads (critical load exceedances) is considered a measure for the risk of harmful effects on sensitive elements of the environment. The magnitude and the geographical distribution of critical load exceedances over Europe vary with the extent to which national emissions of sulfur dioxide, nitrogen oxide and ammonia are reduced. The scientific support of negotiations on emission reductions in the framework of the Convention on Long-range Transboundary Air Pollution (LRTAP) of the UN Economic Commission for Europe has been based on the integrated assessment of sources, including abatement costs, and risks to receptors (e.g. forests, lakes) using critical load exceedances. The shift from a single-pollutant (sulfur) protocol in 1994 to a multi-pollutant protocol in 1999 necessitated an extension of the methods by which critical load exceedances are computed and mapped. The focus changed from the protection of the most sensitive ecosystem against excessive deposition of one pollutant, to an assessment of the accumulated exceedance by more pollutants of all ecosystems. This paper presents and compares the different characterisations ("gap-closure methods") used in those negotiations. It is shown that the approach finally used has several appealing features, but treats the exceedance as a linear damage function, thus going beyond the critical load definition as a simple on-off limit value.  相似文献   

2.
The scientific support of negotiations on emission reductions under the framework of the Convention on Long-range Transboundary Air Pollution of the UN Economic Commission for Europe has been based during the last decade on the integrated assessment of sources, including abatement costs, and risks to receptors (e.g. forests, lakes) quantified by critical loads. The shift from a single-pollutant (sulfur) protocol in 1994 to a multi-pollutant protocol in 1999 necessitated an extension of the methods by which critical loads were computed and mapped. Instead of a single critical load for acidification, methods were now developed to assess the risk of acidifying effects of both sulfur and nitrogen deposition as well as the eutrophying effects of nitrogen on sensitive elements of the environment. Collaboration with a scientific network of 24 national institutions ensured a successful implementation of the proposed methodology across countries. This paper summarizes the methodology, describes the latest input data and presents critical load maps on the basis of which about 98% and 78% of European ecosystems would be protected against acidification and eutrophication, respectively, by the year 2010 according to the multi-pollutant multi-effect protocol.  相似文献   

3.
The Abatement Strategies AssessmentModel, ASAM, has been used to investigateEuropean emission abatement policies for ammoniaand oxides of sulphur and nitrogen. Thesepolicies are designed to reduce the depositionof acidifying substances towards critical loadsdefining the deposition which ecosystems cansustain. Since critical loads are not allattainable the model has been set up to reachvarious intermediate target loads. This paperuses the model to illustrate the sensitivity ofthe derived abatement strategies to the choiceof target load. Particular attention is paidto the various methods of `gap closure',designed to calculate target loads. Thesemethods have been discussed within the frameworkof the UN ECE Task Force on IntegratedAssessment Modelling in its preparations for thenew UN ECE `multi-pollutant multi-effectprotocol' and involve the reduction of the gapbetween the situation in 1990 and the criticalloads. The `gap' can be measured using variousmethods, `area', `ratio' and `accumulatedexceedance'. It is shown that the methods ofdefining target loads have an important bearingon the nature of abatement strategies forpollutants, in terms of the distribution acrosscountries of both costs and benefits. The`accumulated exceedance' approach reflects boththe differing sizes of ecosystem areas indifferent parts of Europe and the differentamounts by which their critical loads areexceeded. It probably reflects much morerealistically the relationship betweendeposition levels and damage to ecosystems.  相似文献   

4.
The technological options currently available to reduce SO2 and NOx emissions including abatement technologies and high efficient energy conversion technologies are reviewed. The energy emission model EFOMENV (Energy Flow Optimization Model-Environment) which takes into account all relevant emission reduction measures is used to determine the cost optimized energy pathway, the ranking of reduction measures and the corresponding costs as a function of given reduction levels of SO2 and/or NOx emissions for different scenarios in selected Central and Eastern European countries. It is shown that restructuring of the energy system is a major emission reduction option in all countries but with a potential varying greatly from country to country depending mainly on the existing structure and the age of the plants and on the development of the energy demand. The emission reduction costs for SO2 in Central and Eastern European countries are 50% to 70% lower than in Western countries due to high potential of fuel/technology switching and energy saving measures. Cost efficient measures to reduce CO2 emissions also lead to a significant decrease of SO2 and NOx emissions.  相似文献   

5.
Vehicle exhaust emissions are significant sources of air pollution in many European countries. Emissions of oxides of nitrogen and volatile organic compounds contribute to transboundary air pollution, and the environmental problems of acidification, eutrophication and tropospheric ozone formation. This paper presents estimates of future exhaust emissions from road vehicles within countries of the United Nations Economic Commission for Europe region for two control scenarios. Alternative regulatory standards are examined including a Current Plans scenario and a Best Available Technology scenario. Calculations presented in this paper suggest that Current Plans could reduce emissions of oxides of nitrogen from road vehicles by about 70 per cent and that the application of Best Available Technology to gasoline and diesel vehicles could reduce emissions by 80 per cent. The paper ends with a discussion of the many interactions between transport and the environment and it is suggested that combinations of regulatory approaches will be needed if the environmental impact of road transportation is to be reduced in the future.  相似文献   

6.
There are concerns over a range of adverse environmental effects resulting from the storage of livestock manures on farms. The objectives of this study were to examine all the likely environmental effects of different storage methods, and to recommend which were the most desirable options.Literature reviews were undertaken to identify the likely environmental consequences of each commonly used storage method, in terms of water pollution risks, odour and ammonia emissions, greenhouse gas emissions and survival of microorganisms during storage. Planning and landscape aspects were considered and the most feasible options for abatement of ammonia emissions were identified. An ‘environmental rating’ for different storage systems was then devised, with the aim of obtaining a balance between water pollution, aerial emissions and other concerns.The environmental rating exercise favoured the more sophisticated and hence most expensive storage methods. No large differences emerged between ratings for slurry systems and solid systems when ease of adding ammonia control measures was excluded. For pigs, slurry systems appear to have a slight advantage, because of the greater ammonia emissions from the solid pig manure. The use of such a rating system could be developed further as more data become available. Whilst the method indicates the relative desirability of systems at a national scale it could be adapted to take account of local considerations or those of individual farm sites.  相似文献   

7.
The RAINS (Regional Air Pollution INformation and Simulation) model was developed at IIASA as an integrated assessment tool to assist policy advisors in evaluating options for reducing acid rain. In recent years, the European implementation of this model has been used to support the negotiations on an updated, effect-based Sulphur Protocol under the Convention on Long-range Transboundary Air Pollution. The development of future strategies for reducing the environmental damage caused by air pollutants requires a multi-pollutant, multi-effect approach. In this context, the RAINS model is being further developed to include ozone. This paper outlines the development of an integrated assessment model for tropospheric ozone, which combines information on the emissions of ozone precursors (NOx and VOCs), the available control technologies and abatement costs, the formation and transport of ozone and its environmental effects in Europe.  相似文献   

8.
Fertiliser nitrogen (N) is essential for maintaining agronomic outputs for our growing population. However, the societal, economic and environmental impacts of excess reactive N from fertiliser is rarely assessed. Here the agronomic, economic and environmental efficacy of three N-fertiliser sources, ammonium-nitrate (AN), urea (U), and inhibited-urea (IU; with NPBT) were evaluated at two grassland sites. Dry matter yield and herbage quality were measured at each silage-cut. Additionally, NH3-N and N2O-N losses were measured and used to calculate the effective N source cost and externality costs, which account for associated environmental and societal impacts. We found no effect of different N sources on yield or herbage quality. However, NH3-N emissions were significantly reduced under the IU treatment, by 48–65%. No significant differences in cumulative N2O emissions were observed. Incorporating externality costs increased fertiliser prices by 1.23–2.36, 6.51–16.4, and 3.17–4.17 times the original cost, for AN, U and IU, respectively, transforming U from the cheapest, to the most expensive of the N sources examined. However, with no apparent yield differences between N-fertiliser sources there is no economic incentive for the land-manager to use the more environmentally and socially acceptable option, unless externality costs are incorporated into fertiliser prices at the point of sale.  相似文献   

9.
Johansson  M.  Alveteg  M.  Amann  M.  Bak  J.  Bartnicki  J.  Ekqvist  M.  Forsius  M.  Frohn  L.  Geernaert  G.  Gimeno  B.  Guardans  R.  Karvosenoja  N.  Martín  F.  Posch  M.  Suutari  R.  Syri  S. 《Water, air, and soil pollution》2001,130(1-4):175-186
The integrated assessment modeling on acid rain has incorporated several related effects and pollutants into a multi-pollutant/multi-effect approach, resulting in complex integrated models and policy assessments. The development and implementation of effects-oriented cost-effective emission reduction strategies in Europe are based on integrated assessment models. The project on national integrated assessment modeling in Finland, Denmark, Spain and Sweden aimed to support the national evaluation of European emission reduction strategies. The tasks covered the comparison of inventories and projections for emissions of sulfur, nitrogen oxides, ammonia and volatile organic compounds, assessment of control techniques and related costs, concentration and deposition scenarios to estimate environmental effects of acidification, eutrophication and ground-level ozone and their temporal aspects, uncertainty analyses on both individual modules and whole integrated models, and dissemination of results to stakeholders. The integrated assessment modeling provided a consistent framework for the harmonization of input data and in-depth scientific research tasks on emissions, pollutant loading and impacts including comprehensive uncertainty analyses, and facilitated the dissemination of knowledge to policy-makers.  相似文献   

10.
采用通气法对设施菠菜和黄瓜在施用生物质炭与翻耕措施下土壤氨气(NH3)排放进行观测,探索设施菜地NH3减排的有效途径.观测表明,设施菠菜与黄瓜土壤NH3排放主要发生在施肥后一周内.在施化肥氮总量300 kg/hm2条件下,设施菠菜不施生物质炭和表施生物质炭处理的NH3排放量分别占总氮投入量的8.00%和10.15%,而...  相似文献   

11.
Air pollutants emissions from traffic are very closely connected to urban air quality, in a local scale, as well as to global problems like climate change, in a large scale. Road transport air pollutants emissions represent, in most cases, a critical parameter for a comprehensive and successful understanding of the mechanisms governing the air pollutants concentrations. Hence, reliable estimations and comprehension of road transport emissions are indispensable in order to set reliable strategies in the direction of air pollution abatement and management of air pollutants and greenhouse gases emissions. In this framework, in the present work, the emissions of air pollutants from road transport in Greece will be presented for the whole period 1990–2009 as it was found that a detailed, accurate and reliable emissions inventory was missing. The whole period emissions variation has clarified the impact of the change in the vehicle fleet, the engine technologies and the fuel quality. The calculated results have revealed that the age of the vehicles and the corresponding engine technology are the critical parameters determining the amount of the pollutants emitted. This was mainly observed in both passenger cars and heavy duty vehicles demonstrating the importance of a renewal programme of the old circulating vehicles in order to set an effective air pollution abatement strategy. Passenger cars were found to be responsible for the major part of most air pollutants emissions except from nitrogen oxides and particulates emissions. Heavy duty vehicles contribute more than 66% to nitrogen oxides and particulates emissions. For the whole time period, all calculated pollutants present a decreasing trend, with the exception of carbon dioxide and nitrous oxide which increase constantly, ranging from −96% for sulphur dioxide to −1% for PM10.  相似文献   

12.
天津市农田氮肥施用氨排放量估算及分布特征分析   总被引:4,自引:1,他引:4  
氮素是作物生长的必要营养元素,氮肥施用过程中,会导致氨的挥发,而氨是形成可吸入颗粒物的重要前体物,为了解天津市农田氮肥施用过程中氨的排放,为天津市空气污染治理提供技术支撑,通过获取天津市不同农作物的不同氮肥种类施用量,依据国家环保部推荐的排放因子法和天津市的年均温度,对天津市农田氮肥施用过程中氨的排放量进行了估算和时空分布特征分析。结果表明,2014年天津市农田氮肥施用氨排放量为17 999.91 t,排放强度为3.27 t·km-2;从氮肥种类上看,尿素是最大排放源,贡献率为83.13%,其次是碳铵(13.83%),其他氮肥占比为3.04%;从农作物类型上看,蔬菜是最大的排放源,贡献率为38.91%,其次是玉米(29.43%)和小麦(19.66%),其他作物占比为12.00%。氨的排放系数具有明显的时间特征:中午高,夜间低;8月份最高,1月份最低。在各区县中,武清区氨排放量最大,贡献率为27.06%;津南区氨排放量最小,贡献率为1.14%;另外,宝坻区和蓟县的氨排放量也较高,贡献率分别为20.71%、17.86%。氨具有较强的空间分布差异性,在有氮肥施用的农田排放较高,其他区域排放较低。因此在控制天津市农田氮肥施用氨排放中应加强对武清区、宝坻区、蓟县等区县6—8月份蔬菜种植过程中尿素的科学施用。农田氨的时空分布特征可为天津市空气污染的防治提供科学依据。  相似文献   

13.
Integrated Assessment Models were successfully used to provide input to the negotiations for the Oslo Protocol on Further Reductions of Sulphur Emissions, finalized within the United Nations Economic Commission for Europe Convention on Long-range Transboundary Air Pollution in Oslo in June 1994. The techniques developed within this framework will be extended now to the simultaneous analysis of sulphur and nitrogen deposition. In addition to acidification, atmospheric deposition of nitrogen contributes to eutrophication of certain ecosystems, through a nutrient effect, and originates from the long-range transport of emissions of both oxidised and reduced nitrogen (NOx and NH3). Modelling reductions in nitrogen deposition thus introduces a need to establish multi-pollutant multi-effect modelling techniques. This paper investigates the development of a model set up to examine reductions of these pollutants in an economically and environmentally efficient manner. The control of nitrogen deposition encompasses action across several economic sectors, particularly the power, transport and agricultural sectors. Combining sulphur and nitrogen deposition limits on a European scale will require a flexible modelling approach and the issues governing possible approaches are presented.  相似文献   

14.
为促进奶牛养殖场的大气氨排放控制,形成奶牛养殖场粪便中氨排放的阻控体系,该文在冬季和夏季对内蒙古呼和浩特地区奶牛养殖场A和奶牛养殖场B的大气、牛粪和牛尿进行了采样试验分析,研究了2种奶牛养殖场不同处理工艺的氨排放特征。静态试验结果表明,奶牛养殖场A和奶牛养殖场B氨气排放浓度最高的是氧化塘处理工艺、预处理工艺,分别为冬季0.862,3.169 mg/m3,夏季2.785,2.130 mg/m3。动态试验结果表明,牛粪的氨排放系数要高于牛尿1.85倍,奶牛养殖场A和奶牛养殖场B平均排放系数分别为29.23%、49.36%。奶牛养殖场A和奶牛养殖场B总大气氨排放量分别为冬季172.69,1 101.00 kg/d,夏季284.70、1 395.32 kg/d。2种处理工艺冬季和夏季大气氨含量均满足畜禽场环境质量标准,但超过人居空气质量标准。  相似文献   

15.
Ammonia emissions originate from different and widely distributed sources. The bulk of anthropogenic NH3 emissions are connected with agriculture and a smaller part with industry. The default emission factors recommended by the Economical Commission for Europe are applied to evaluate NH3 emissions from the former USSR. The following categories of agricultural activities are considered: cattle, pigs, poultry, horses, sheep, goats, fur animals, rabbits, reindeers and fertiliser application. Human and home pet metabolism as a source of NH3 is also considered. Industrial sources include combustion processes and production of fertilisers, ammonia, coke. Emissions from landfills are also considered. Uncertainties of emission values for each category of sources are estimated. Ammonia emissions are calculated separately for all former republics for the year 1990. The total emissions for Russia are spatially distributed over the territory with 1° × 1° resolution. The data on NH3 emissions can be used in model calculations of long-range (transboundary) transport of acidifying compounds.  相似文献   

16.
氨气是大气中唯一的碱性气体,减少氨排放对控制大气雾霾有重要作用,畜禽养殖业是重要的氨气排放源,科学评估不同环节的氨气排放量及减排潜力具有重要意义。本文根据文献资料总结了国内外不同畜禽养殖舍的氨排放因子情况、主要减排技术及效率,并结合第二次全国污染源普查获得的全国主要畜禽采用机械通风养殖场的数量和养殖量,对中国分地区、分畜种密闭式畜舍外排空气的氨减排潜力进行了分析。结果表明:中国机械通风畜舍外排空气氨气年减排潜力为26.56万t,主要来自生猪、蛋鸡和肉鸡三种畜禽,其减排潜力分别为10.18万t、7.73万t和6.75万t,三种畜禽舍减排潜力占比92.8%;从地区上看,主要可实施地区为华东区、中南区和华北区,氨气减排潜力分别占全国的35.1%、26.9%和14.9%。建议开展密闭式生猪、蛋鸡和肉鸡舍氨减排设施建设,可为全国氨减排和大气环境质量改善提供保障。  相似文献   

17.
不同水氮管理下稻田氨挥发损失特征及模拟   总被引:8,自引:5,他引:8  
为了探讨减少稻田氨挥发的合理水氮管理措施,基于田间试验资料,分析了不同水氮管理稻田氨挥发损失规律及其交互影响,并用DNDC(土壤碳氮循环模型)模型模拟了节水灌溉条件下不同氮肥管理稻田氨挥发损失动态特征。结果表明,控制灌溉和实地氮肥管理的联合应用既大幅降低了稻田氨挥发峰值,又降低了稻田大部分无施肥时段的氨挥发损失,稻田氨挥发损失量为39.63kg/hm2,较常规水肥管理稻田降低44.69%。采用DNDC模型模拟节水灌溉条件下不同氮肥管理稻田氨挥发损失量是可行的,稻季氨挥发总量模拟值与实测值相对误差均在±10%以内。节水灌溉和实地氮肥管理的水氮联合调控显著降低了稻田氨挥发损失量,且实地氮肥管理对氨挥发损失降低的贡献率要大于节水灌溉。该文研究结果可为稻田的水肥科学管理,减少稻田氨挥发损失提供依据。  相似文献   

18.
2018年6-11月在华北露地茄田设置不施肥处理(CK)、常规施氮处理(N1)、减氮20%处理(N2)、减氮50%处理(N3)、减氮20%并施用抑制剂包膜尿素处理(N2I)及减氮20%并增施生物炭(N2B)6个处理。测定并分析不同氮肥减施综合方案对作物氮肥利用率、土壤氨挥发及N2O排放的影响。结果表明:(1)与常规施氮处理(N1)相比,减氮20%(N2)对茄子产量无显著影响,减氮50%处理(N3)茄子显著减产。施用抑制剂包膜尿素(N2I)或添加生物炭(N2B)可提高作物氮肥利用率。(2)土壤氨挥发、N2O排放与施肥关系密切,各施肥处理的氨挥发、N2O排放量均高于不施肥处理(CK),两种气体的排放系数分别为9.6%~14.8% (氨)和0.9%~1.1%( N2O),排放通量峰值均出现于施肥之后。(3)与常规施氮(N1)相比,N2、N3、N2I和N2B的土壤氨挥发累积量分别降低20.3%、48.6%、41.7%和30.7%。在不影响产量的前提下,减氮20%并施用抑制剂包膜尿素处理(N2I)减排效果最好。(4)与常规施氮(N1)相比,N2、N3、N2I和N2B的N2O累积排放量分别降低21.5%、41.7%、44.2%和31.6%。N2I处理的累积排放量远低于常规施氮(N1)处理,与减氮50%处理(N3)的N2O累积水平相当。综上,减氮20%并施用抑制剂包膜尿素处理对蔬菜产量无显著影响,氮肥利用率有一定程度提高,且对环境风险小,主要体现为氨挥发和N2O减排效果显著,成本适中,是华北地区露地茄田增效减排的优选推荐方案。  相似文献   

19.
Atmospheric budgets of reduced nitrogen for the major political regions of the British Isles are investigated with a multi-layer atmospheric transport model. The model is validated against measurements of NH3 concentration and is developed to provide atmospheric budgets for defined subdomains of the British Isles. The study shows that NH3 emissions, transport and deposition in a specific region can have profound effects on the composition of the atmosphere over other regions. An important feature is the high export of reduced nitrogen from Republic of Ireland and Northern Ireland to England and Scotland. England is also a net exporter of reduced nitrogen. By contrast, Scotland and Wales are approximately “ammonia neutral” as import of reduced nitrogen roughly balances export. Overall, only 7% of reduced nitrogen in the British Isles is derived from non-British Isles sources (29 kt N yr?1), compared with emissions of 387 kt N yr?1. Most of the reduced nitrogen is deposited in the British Isles (64%), while 36% is exported (148 kt N yr?1).  相似文献   

20.
Odorous emissions from manures have become a significant problem. Preliminary work on composting hog manure with sawdust had indicated that intermittent aeration could reduce ammonia emissions during this process. This paper presents results from four additional runs with a total of 22 pilot-scale vessels that have confirmed that ammonia emissions are affected by aeration. The pilot-scale vessels consisted of insulated, stainless steel, 205 L drums that either received continuous (high/low rate, thermostatically controlled blowers) or intermittent (5 min on high rate, 55 min off) aeration. Ammonia emissions, air flow rates, carbon dioxide production, oxygen utilization, and temperatures at four locations in each vessel were monitored. Ammonia emissions under intermittent aeration were roughly 50% less than those from the continuously aerated vessels. However, this appeared to result more from total air flow than from the aeration technique used. A linear regression of emissions versus total air flow data for all vessels yielded a fit of y = 0.1309x + 29.385 (y being total ammonia emitted [in g of N] and x being total air flow [in kg]) with an R2 = 0.6808. Since air flow termination was relatively arbitrary, this only means basically, that ammonia emissions were doubled for a quadrupling of air flow. Under intermittent aeration, the minimum oxygen level in the exhaust air occasionally dropped to as low as 1%. So the aeration pattern used probably represents the lowest one suitable for maintaining aerobic conditions. Within this constraint, however, lower air flow appears to be suitable for reducing odorous ammonia emissions.  相似文献   

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