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1.
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Concentrations of Mn from soil dust and anthropogenic emissions were studied in the aerosols collected at Mayville, NY. The southwest quadrant of this rural site has numerous Mn-emitting sources. Aerosols arriving from this quadrant contained 80–90% Mn of anthropogenic origin, the remainder was soil derived. Bivariate analysis showed a good linear correlation between noncrustal Mn and Fe, indicating that anthropogenic Mn was mainly derived from the iron and steel industry. Aerosols with relatively high Mn concentrations and enrichments were also encountered during the study period. These were attributed to nonferrous industries such as silico-manganese alloy, synthetic pyrolusite and Mn chemical manufacturing plants. Comparison of concentrations, enrichment factors and ratios of the two elements, Mn and Fe, in these aerosols and in aerosols from several midwestern cities located in the vicinity of Mn-emitting sources attested to the inferences drawn above. Several Mn-emitting sources in the States of Ohio and Pennsylvania were shown to be causative for the high noncrustal Mn concentration at Mayville relative to those seen in rural aerosols from Ashland County, OH, and Shenandoah Valley, VA as well as for the relatively high ratio of noncrustal Mn/Se reported for the lower midwest signature in our earlier study.  相似文献   

3.
Acid deposition in the eastern U.S. during a spring frontal storm from 1 to 5 May 1985 is analysed using the STEM-II acid deposition model. Nitrate formation is dominated by gas-phase production processes, with wet and dry deposition contributing equally to the total domain nitrate deposition. In-cloud sulfate production accounts for 60% of the total sulfate production, while wet deposition dominates the total sulfate deposition. Oxidation of S(IV) by hydrogen peroxide is the most important sulfate formation pathway. Hydrogen peroxide is found to exist in excess of S(IV) in cloud and rainwater in the storm front and at altitudes above 2 km. Production rates of sulfate in the high sulfur source regions are significantly lower (up to an order of magnitude) than in the moderate or low source regions. Model predictions are shown to capture the major features of the observed deposition.  相似文献   

4.
The high-speed rail (HSR) network in China has experienced rapid development since the2000s.In 2016,the State Council of the People’s Republic of China issued a revised version o the“Mid-and Long-term Railway Network Plan”,detailing the expansion of the railway net work and construction of an HSR system.In the future,the HSR construction efforts in China will further increase,which is considered to impact regional development and air pollutan emissions.Therefore,in this paper,we apply a transpor...  相似文献   

5.
The National Environmental Policy Act of 1969 (NEPA) requires that an Environmental Impact Statement (FIS) be prepared whenever a federal action is considered that could result in a significant impact on the environment. Such actions include the issuance of construction or operating licenses for nuclear facilities and power plants, hydroelectric dams, or the diversion of water from rivers and lakes. An EIS is usually required if federal funds are involved. The U.S. Environmental Protection Agency and U.S. Council for Environmental Quality have developed guidelines and regulations for the preparation of an EIS.An EIS is not a scientific report. It is a legal document whose primary function is its use by decision-making agencies in approving or not approving the proposed federal action. The EIS is also used to inform the public and other government agencies of the environmental impacts of the proposed facility. The NEPA process allows public input into the decision-making process. An EIS should be short and concise, analytical, conclusory, be written for a non-technical audience, discuss the pros and cons of the proposed facility, and examine the impacts of all alternatives to the proposed action. The EIS should identify all adverse environmental impacts that cannot be avoided. The conclusions reached in the EIS should be clearly stated and supported by discussions and data in the text and by references to show that the agency has made the necessary analyses.The paper discusses the purpose and contents of these documents and the environmental procedures used in the U.S.A., especially as they relate to nuclear power plants.  相似文献   

6.
美国的野生动物保护   总被引:1,自引:0,他引:1  
本文主要介绍了美国的野生动物法及其法律构架,美国濒危物种法是顶法律典范,它不仅能保护栖息地,还能保护列入濒危物种清单上的具体动物。  相似文献   

7.
The spatial and temporal variability of the daily 1-h maximum O3 concentrations over non-urban areas of the eastern United States of America was examined for the period 1985–1990 using principal component analysis. Utilization of Kaiser's Varimax orthogonal rotation led to the delineation of six contiguous subregions or “influence regimes” which together accounted for 64.02% of the total variance. Each subregion displayed statistically unique O3 characteristics and corresponded well with the path and frequency of anticyclones. When compared to the entire domain, the mid-Atlantic and south subregions observe higher mean daily 1-h maximum concentrations. Concentrations are near the domain average for the northeast and southwest subregions and are lowest in the Great Lakes and Florida subregions. The percentage of observations exceeding 120 ppb were greates in the mid-Atlantic and southwest subregions, near the domain average in the northeast and south subregions, and lowest in the Great Lakes and Florida subregions.Examination of the time series of the principal component scores associated with the subregions indicated that Great Lakes and mid-Atlantic subregions tend to observe a stronger seasonal cycle, with maximum concentrations occurring during the last week in June and first week in July, respectively. The strength of this seasonality is weakened for the northeast and south subregions and its timing delayed, until the end of July and the first of August, respectively. The southwest subregion experiences a greatly diminished seasonality, with maximum concentrations delayed until the middle of August. The seasonality found in the Florida subregion is unique in both its strength and timing, as the highest concentrations consistently occur during the months of April and May. The time series were then deseasonalized and autocorrelations and spectral density estimates calculated, revealing that persistence is much more prevalent in the Florida (autocorrelation significant to a lag of 4 days), south (3 days) and southwest (3 days) subregions. Conversely, autocorrelations are only significant to a lag of one day in the northeast and two days for the Great Lakes and mid-Atlantic subregions.  相似文献   

8.
Natural hydrocarbon emissions from both forests and agricultural lands have been estimated on a regional basis for the U.K. The results of this study suggest total emissions are significantly higher than is currently accepted, with the major forested areas of Scotland, Wales and the north of England dominating the area contributions. Non-methane hydrocarbons (NMHC) emitted from natural sources are estimated at 211 × 103 tC yr−1 which represents 13% of the total NMHC emissions in the U.K.  相似文献   

9.
为分析生物气溶胶释放对人群潜在影响风险的情况,利用CALPUFF模型定量模拟了2019年7月24~8月20日中牧兰州生物药厂含菌气溶胶扩散、浓度空间分布、对人群潜在健康风险,并结合公开报道的检测数据开展验证.结果显示:生物药厂的含菌气溶胶排放源附近高值区主要集中于厂区四周,影响范围主要以厂区为中心,并向四周逐渐扩散;检测结果中兰州兽研所1#,兰州大学2#地区健康风险比例41.49:1,在模拟的相对风险大小的误差区间(36.15±8.48)范围内,说明本研究含菌气溶胶对人群潜在影响风险的模拟结果可信.  相似文献   

10.
魏旭  邱新 《世界环境》2009,(3):59-61
起源 20世纪60年代末70年代初的环境社会运动象征着美国环境意识的逐步觉醒。也成为了许多环境法律制度的起源。在此期间,针对频繁而缺乏管制的大气污染、水污染、森林覆盖率急剧降低、野生物种快速减少等严重环境问题,美国国会在社会压力之下通过了现有主要的联邦环境法律。而整个社会环保意识的提高对环境法学者和学生带来了新的使命,  相似文献   

11.
基于WRF-CMAQ空气质量模型,采用开关污染源排放的敏感性试验方法,定量分析了淮海经济区核心区污染排放对京津冀区域、"2+26 "大气污染传输通道城市、汾渭平原地区和长三角区域PM2.5的贡献.结果表明,对京津冀区域,污染贡献比例最大值出现在10月份,同时对不同城市的贡献值在10%以内变化;对" 2+26"大气传输通道城市,影响的时空差异变化明显,其中对聊城市、菏泽市和济南市的贡献值均超过了10%;对汾渭平原地区的贡献总体较弱,最大贡献值低于5%;对长三角区域,贡献值在不同城市间的时空差异变化明显.考虑到淮海经济区地处京津冀和长三角过渡地带,且对京津冀和长三角区域PM2.5影响较大,建议尽快将淮海经济区核心地区纳入国家大气污染重点控制区.  相似文献   

12.
《环境保护》2015,43(2)
对美国野生动物保护的濒危物种名录制度、栖息地保护制度、野生动物保护税费制度和野生动物保护志愿者制度做了详细介绍,指出美国野生动物保护起步早、发展历史悠久、野生动物保护法律制度健全。并结合我国实际,提出我国现阶段野生动物保护要注重濒危物种价值与经济利益的平衡;设定野生动物及栖息地保护红线;拓宽野生动物保护资金渠道;实行志愿者数字化管理制度。  相似文献   

13.
Results are reported from a series of cloud chemistry simulations designed to evaluate the sensitivity of precipitation sulfate concentrations to changes in the shape and mass of the preexisting gas phase profiles. Linearity factors relating chemical inflow conditions to depositio are evaluated. The height from which any given fraction of the sulfur in precipitation came in stratiform storms was found to be approximately equal to the height at which the corresponding fraction sulfur was located. This source height was greater for convective storms. Changes in the total sulfur generally resulted in an almost proportional change in the resulting precipitation sulfate concentrations. Because stratiform storms rely more strongly on the initial gas-phase profiles to define the available oxidant at a given height, the deposition and SO2 linearity factors associated with such storms were found to be more sensitive to the initial height dependence of the ratio [SO2] and [H2O2] than was found for convective storms. The deposition and the linearity factor for convective storms were found to be more strongly dependent on the total column mass of these species. The precipitation sulfate concentration and linearity were found to be generally insensitive to perturbations in the fine structure of the initial gas-phase profiles.  相似文献   

14.
泰山降水化学及大气传输的研究   总被引:24,自引:4,他引:24  
为了解泰山降水的化学组成特征及其来源,于2004年7月至12月间在泰山上采集了23场降水样品,进行了pH值、电导率的测定、主要水溶性阴阳离子的分析以及每场降水的后推气流轨迹分析.结果表明,降水pH的雨量加权均值为4.74,电导率的雨量加权均值为2.26mS·m-1,泰山降水已受到酸性污染;降水中浓度较高的阳离子是NH4 和Ca2 ,雨量加权均值浓度分别为50.62和29.04μeq·L-1,浓度较高的阴离子是SO42-和NO3-,雨量加权均值浓度分别为70.32和23.44μeq·L-1;SO42-/NO3-、NH4 /Ca2 当量浓度比的平均值依次为3.41、2.13.对降水的化学组成作了相关性分析,发现NH4 、Ca2 、SO42-、NO3-浓度之间具有很好的相关性;通过气流轨迹分析发现酸性最强的降水气团来自于我国的南部地区或沿途经过华东地区,离子浓度最高的降水气团来自于我国的北部地区或欧洲大陆,来自东亚地区的降水气团的离子浓度最低.  相似文献   

15.
美国保护地体系研究   总被引:2,自引:0,他引:2  
世界自然保护联盟(IUCN)提出的保护地体系是世界性的保护地管理体系,而美国以国家公园系统为代表的保护地管理体系,是世界上最为科学、完善的体系之一.本文结合文献,介绍IUCN体系的定义、分类及美国保护地体系的管理现状,分析IUCN体系在美国的应用情况.研究美国的保护地体系建设,对于同样是世界自然文化遗产资源大国的中国,有其积极的意义和作用.  相似文献   

16.
Numerical modelling of fire-related smoke haze episodes in Southeast Asia is important for both prediction and assessment of atmospheric impacts, especially when observational data are fragmentary, as is the case in Indonesia. This work describes the atmospheric fate of smoke particles emitted during the 1997 Indonesian fires modelled with a regional atmospheric chemistry model. We established a new fire emission inventory and calculate that 55 teragram (Tg) of particulate matter and 1098 Tg of carbon were released during this fire episode. Our emission estimate is an intermediate value compared with other studies. Utilising different scenarios, we demonstrate the variable atmospheric impacts of surface vegetation fires and peat soil fires separately and also investigate the sensitivity of smoke dispersion to the differing meteorological conditions of an El Niño and a normal year. When peat fires are included in the emission inventory, modelled ambient particle concentrations exceed the ambient air quality standard across transboundary scales. In a scenario including only surface vegetation fires, ambient air quality standards are exceeded only in areas close to the main fires. This scenario demonstrates the prominent role of fires in peat areas in causing regional air pollution episodes. In years with normal meteorological conditions, intermittent precipitation and associated wet deposition during the dry season are predicted to remove most of the particulate emissions close to the sources. Strongly reduced rainfall and generally stronger southeasterly winds during El Niño years provide favourable conditions for larger scale smoke haze pollution.  相似文献   

17.
Continually increasing amounts of municipal solid waste (MSW) and the limited capacity of the existing waste management system in Phuket have led to the consideration of integrated waste management system (IWMS). Life cycle assessment (LCA) was employed to compare the greenhouse gas emissions expressed as global warming potential (GWP) of the existing waste management system (the base scenario) and other three IWMSs for Phuket MSW. Besides incineration and landfilling, the proposed scenarios include 30% source separation for recycling (scenario 2), anaerobic digestion (scenario 3) and both (scenario 4).The functional unit is set as 1 t of Phuket MSW treated. Results from the impact assessment of the base scenario shows that the net GWP is 1006 kg CO2 equivalent. Landfilling contributes to the highest potentials of this impact. The results from a holistic comparison show that scenario 4 is the best option among all the scenarios, contributing GWP of 415 kg CO2 eq., whereas the base scenario is the worst. The emission of greenhouse gas from landfilling is reduced by the introduction of landfill gas recovery and utilization for electricity production. By assumption, 50% recovery of landfill gas leads to the GWP reduction around 58% by total GWP of landfilling and 36% by the net GWP of the whole system in the base scenario. The study suggests that a policy that promotes source separation should be pursued, preferably combined with the application of landfill gas recovery for electricity. Policy promoting recycling is favorable over anaerobic digestion in the situation that both treatment systems could not be established at the same time. The major conclusion from the study is that results from the LCA can support Phuket Municipality for decision-making with respect to planning and optimizing IWMS. It can benefit other municipalities or policy makers to apply in their waste management projects.  相似文献   

18.
Precipitation chemistry data derived from more than six years of concurrent sampling under the MAP3S and NADP/NTN protocols at the Penn State site in rural Pennsylvania are compared. Preprocessing of the data (sample and gage depths, concentrations of H3O+, SO42−, NO3, NH4+) included aggregating the event and daily MAP3S data into weekly averages that coincide with the weekly data of the NADP/NTN program. A simple statistical model was applied to the differences of the paired data to look for systematic biases between the networks. The most notable bias occurred for ammonium concentration (NADP/NTN low), a finding consistent with other studies. A minor, but statistically significant, bias was also found for sulfate coccentration (NADP/NTN high). Both the ammonium and sulfate biases may be related to the relatively long time that the NADP/NTN samples remain in the field, thus strengthening arguments in favor of daily sampling protocols. The hydronium and nitrate concentrations exhibited remarkably high levels of comparability between the daily and weekly protocols. Overall, the data from the MAP3S and NADP/NTN networks are comparable, with the possible exception of ammonium, for some applications. The field results from about two years of duplicate sampling under the MAP3S protocol demonstrate that measurement precisions of only a few percent are possible when the protocol is consistently followed and the equipment is well maintained.  相似文献   

19.
In recent years, pesticide usage in the United States has increased markedly. As measured in 1980 for the U.S.A., there were: (1) more than 45 000 individually products registered; (2) more than 1500 active ingredients involved; and (3) about 2.5 billion pounds of active ingredients used annually. Pesticide usage in agriculture has probably peaked and will probably level off and may even decrease in the 1980's because of public health concerns, environmental concerns, lower dose levels of newer pesticides, and the introduction and use of integrated pest management programs and bio-control programs.  相似文献   

20.
叶敏华  蔡闻佳  王灿 《中国环境科学》2013,33(10):1869-1875
跨区电力传输作为新的区域间能源调配形式将会改变我国未来各区域能源使用、大气污染物排放、温室气体排放等的发展路径,模拟、分析这种影响能为统筹协调全国以及区域的能源资源使用策略和电力行业节能减排相关政策提供参考.本研究应用基于区域电网的中国电力行业优化模型(BOMCES-ED),结合特高压输电线路的相关发展预期,以2010年我国各区域电网的发电装机信息为基准年数据,模拟研究了跨区电力传输对各区域电力行业发展以及环境排放造成的影响.结果显示,到2020年,最大的电力输出区域西北电网因电力输出而导致的电煤消耗量增加12351.2万t,SO2、NOx、CO2和Hg排放增加量分别达到22.1万t、11.6万t、2.28亿t和3.80t.由跨区电力传输导致的区域间环境排放和环境健康损失转移需要引起关注.  相似文献   

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