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1.
在研究分析国内外现有光污染相关技术规定的基础上,结合我国城市光污染现状,为解决我国城市光污染中危害最严重的典型问题,将我国城市光环境污染划分为玻璃幕墙眩光污染、交通道路眩光污染、居住区光污染、室外光污染源4个重点监测项目,并针对具体项目初步提出了玻璃幕墙反射眩光监测控制值、交通道路眩光监测控制值、居住区光污染监测控制值和室外光污染源监测控制值。  相似文献   

2.
通过对广州市玻璃幕墙建筑在不同季节、不同时段光环境影响的监测,分析影响玻璃幕墙建筑光污染的重要因素,评价了玻璃幕墙建筑在不同季节、不同时段造成光污染的危害,估算玻璃幕墙建筑的光环境污染程度及范围,提出了玻璃幕墙建筑光污染的防控建议,以期为城市玻璃建筑光污染控制与管理提供科学依据。  相似文献   

3.
基于南充市主城区6项大气污染物浓度数据,研究了2014-2020年南充市的空气质量指数、空气质量指数等级和首要污染物的时序分布。结果表明:随着大气污染防治的开展,南充市大气污染物浓度逐渐下降,出现首要污染物的天数逐年减少,空气质量逐步提高。受污染物节律性影响,空气质量呈现明显的季节差异,冬季空气质量最差,春季次之,夏季污染相对较轻,秋季最轻。首要污染物类型的季节分布特征表现为冬季出现首要污染物天数最多,春季和夏季次之,秋季最少。春、秋、冬季以PM2.5污染为主,夏季以O3污染为主。从全年来看,与O3相比,PM2.5对空气质量的影响更为突出。在持续控制大气污染物排放总量的同时,精细化协同管控细颗粒物、氮氧化物、挥发性有机物和二氧化硫排放将有助于现阶段的大气污染防治。  相似文献   

4.
通过采集淮南市6个功能区四季的PM_(2.5)样品,运用GC-MS仪测定样品中PAHs含量并分析其主要来源。结果表明:该市PM_(2.5)中PAHs质量浓度年均值为31.06 ng/m~3,呈现冬季污染程度最重,夏季最轻,采矿区商业区工业区文教区居民区对照区的特征;夏季PAHs以3环和4环为主,春、秋、冬季以4环、5环和6环为主;6个功能区均以4环PAHs为主;PAHs主要来源为煤燃烧、机动车尾气排放、生物质燃烧及焦炉挥发,其中燃煤和机动车尾气污染贡献最大。  相似文献   

5.
分析了2018年春节期间京津冀及周边区域空气质量状况,结果表明,京津冀及周边区域2018年春节期间空气污染较重,以石家庄、邢台、邯郸、晋城、长治为中心的区域污染最重,此次重污染过程呈污染范围大、持续时间长的特点。受微风、高湿、逆温等不利气象条件影响,颗粒物污染不断积累和二次转化。除夕(2月15日)至初六(2月21日),北京首要污染源为机动车尾气源,张家口、保定、太原、郑州为燃煤源,太原和廊坊烟花源占比高于其他城市。自除夕(2月15日)下午开始,区域内各城市烟花爆竹燃放相关离子浓度有不同程度的增加,北京、保定烟花源贡献率与贡献浓度与2017年春节期间相比有所下降。2018年春节期间PM2.5浓度明显高于2015—2017年,区域南部空气质量较差,重污染区域主要集中在以石家庄、邢台、邯郸、长治、晋城为中心的区域。  相似文献   

6.
2020年12月底,以生态旅游业为主的重庆市渝东南地区出现了一次较为罕见的PM2.5污染过程,持续时间长且污染程度重。以渝东南地区武隆区为例,应用污染特征雷达图、后向轨迹模型及潜在源污染贡献估算等方法分析了本次PM2.5污染的特征及来源,结果表明:(1)在污染前期主要受扬尘、燃煤和机动车等污染排放影响,污染源直接排放贡献较大;中、后期污染受二次颗粒物影响显著,扬尘影响也较为明显。(2)污染期间的气流轨迹均为短距离输送,轨迹主要来自东北方向(65%)。(3)除自身污染排放贡献外,渝东北地区和主城都市区是武隆区PM2.5污染的主要潜在源区,对武隆区传输贡献占比超50%。  相似文献   

7.
通过统计2019年晋江石砻断面水质周报数据,分析该断面水质指标季节变化,并用单因子指数法评价其水质.结果表明:pH值全年变化范围为6.68-7.54,季节均值顺序为秋季<冬季<春季<夏季;DO全年变化范围为5.0 mg/L-9.7 mg/L,春冬季高于夏秋季;1Mn全年变化范围为1.5 mg/L-3.4 mg/L,春夏季略高于秋冬季;NH3-N全年变化范围为0.08 mg/L-0.51 mg/L,表现为春冬季高,夏秋季低;TP全年变化范围为0.042 mg/L-0.169 mg/L,表现为春季最高,夏冬季次之,秋季最低;Cr(Ⅵ)全年稳定在0.002 mg/L.单因子评价法显示,晋江总体符合Ⅲ类水质标准;使用t检验法发现,TP与NH3-N显著相关,可能是由于二者受到相同污染源的影响所致.  相似文献   

8.
夜间人工照明在给人们的生活生产带来诸多便利的同时,也产生了一系列生态影响,导致了夜间光污染这一新的环境问题。然而,目前对于夜间光污染的监测和防控还未得到重视。针对我国对生态环境保护和建设的新要求,简述了夜间光污染对于天文观测、人类身心健康、交通安全、生态系统和能源浪费方面的影响,列举了夜间光污染的监测方法,包括实地测量和卫星遥感监测。针对我国目前夜间光污染防治现状,提出了完善法律法规、开展监测和评价、健全监管体系、推动宣传和教育等方面的防治建议。  相似文献   

9.
以无锡市望虞河西岸河网区为研究区域,于2018年12月—2019年9月分冬、春、夏、秋4个季节采集了上覆水和沉积物样本,研究氮磷营养因子在沉积物-上覆水界面的释放规律,探究主要水质指标、沉积物氮磷和重金属含量的时空分布特征。结果表明:研究区域内的水质状况不佳,主要是氮含量超标,污染严重的点位集中在人类活动较为密集的市区和工业区;受上覆水氮磷浓度、溶解氧浓度等变化的影响,沉积物营养盐含量季节变化明显,污染状况较为严重,75%的点位属于中度和重度污染;沉积物重金属含量季节变化不显著,部分重金属的空间分布特征相似,污染程度排序为Zn>Cd>Cu>Pb>Ni>Cr>As。  相似文献   

10.
为探讨2013—2019年京津冀及周边地区"2+26"城市PM_(2.5)重污染时空演变特征,对"2+26"城市7年间的大气环境监测网数据进行了统计分析。在年际变化上,重污染过程次数逐年下降,发生时长和强度分3个阶段大幅降低。相比2013年,2014—2016年重污染小时数、天数和峰值浓度均降低了一半左右,2017—2019年则下降了约80%。目前,区域重污染过程以持续1~2 d的较短过程为主。在季节分布上,全年重污染集中于秋冬季,其中冬季占比从60%升至80%,尤其是1月的重污染占比最高且有逐年增加趋势。在空间分布上,区域差异明显缩小,呈相对均匀化趋势,区域污染中心有所南移,南部的冀南豫北区域在区域重污染中的占比呈上升趋势。在污染成因基本类型上,污染排放导致的积累型为主要类型,占比约90%;沙尘型及烟花爆竹燃放型的总占比约为10%,虽然其占比较低,但近年的比重较稳定,未有明显下降趋势。  相似文献   

11.
An important research area in life sciences is devoted to modeling, prediction, and dynamics of gene-expression patterns. As clearly understood in these days, this enterprise cannot become satisfactory without acknowledging the role of the environment. To a representation of past, present, and most likely future states, we also encounter measurement errors and uncertainties. This paper surveys and improves recent advances in understanding the foundations and interdisciplinary implications of the newly introduced gene–environment networks, and it integrates the important theme of carbon dioxide emission reduction into the networks and dynamics. We also introduce some operational and managerial issues of practical working and decision making, expressed in terms of sliding windows, quadrants (modules) of parametric effects, and navigating (controlling) between such effects and directing them. Given data from DNA microarray experiments and environmental records, we extract nonlinear ordinary differential equations that contain parameters that have to be determined. For this, we employ modern (Chebychevian) approximation and (generalized semi-infinite) optimization. After this is provided, time- discretized dynamical systems are studied. A combinatorial algorithm with polyhedra sequences allows to detect the region of parametric stability. Finally, we analyze the topological landscape of gene–environment networks with its structural (in)stability. By embedding as a module and investigating CO2 emission control and figuring out game theoretical aspects, we conclude. This pioneering work is theoretically elaborated, practically devoted to health care, medicine, education, living conditions, and environmental protection, and it invites the readers to future research.   相似文献   

12.
In this article a comprehensive approach for the evaluation of possible health effects in an environmental impact assessment (EIA) is described, illustrated with the example of Amsterdam Airport Schiphol. Unlike many EIAs, we estimated quantitatively the impact of aircraft-related pollution in terms of the number of affected people for aircraft noise annoyance, odour annoyance and hypertension. In addition, an analysis of health registry data on cardiovascular and respiratory diseases and a short survey on annoyance and risk perception were carried out. The scope of a health impact assessment depends on the situation, available knowledge and data, concern in the population about the impact and the number of people concerned. It is important to pay attention to the perception of risks and concerns from all parties involved. Moreover, the results demonstrate that far more people outside the area for which standards apply were affected than inside.  相似文献   

13.
The San Francisco Bay estuary isused by over one million shorebirds during springmigration and is home to several hundred thousandduring the winter. Most shorebird use occurs in thesouthern reach of the estuary (South Bay). Thereduced water circulation and discharge fromindustrial sources in the South Bay are responsiblefor the highest levels of some trace elements in theestuary. Wintering shorebirds have been found to havestrong site fidelity to areas as small as a fewkilometers in the South Bay, which may increase theirexposure to contaminants near local point sources. Inaddition, different shorebird species foraging at thesame site have been shown to have differentcontaminant burdens. Thus, our objectives were totest whether contaminant burdens differed by species,or whether contaminant burdens differed in shorebirdscollected at adjacent sites. We examined thecontaminant profiles of two species of shorebirds,long-billed dowitchers (Limnodromus scolopaceus)and western sandpipers (Calidris mauri) thatforage together at two sites, Hayward and Newark,separated by 8 km in the South Bay. We usedmultivariate analysis of variance tests to compare thecomposition of 14 elemental analytes in their livertissues and estimated their molar ratios of Hg and Se. Composite samples were used for contaminant analysesbecause of the small body size of the shorebirds. Seven elemental analytes (Ag, Ba, Be, Cr, Ni, Pb, V)were below detection limits in a majority of thesamples so statistical analyses were precluded. Inthe measurable analytes (As, Cd, Cu, Hg, Mn, Se, Zn),we found no significant intra-site differences ofcontaminant profiles for the two species. We pooledthe samples to examine inter-site differences andfound significant differences in contaminant profilesbetween shorebirds at the neighboring sites (P = 0.03). Shorebirds at Newark had higher (P < 0.05) concentrations of As, Cd, and Se than those at Hayward. Dowitchers at Newark had concentrations of Hg and Se which were highly correlated (P < 0.003) in a mean molar ratio of 1:19, similar tothat reported in other birds. In the larger dowitcherspecies, we also examined exposure to 20organochlorine compounds. Organic analyses showedthat the dowitchers had been exposed to DDE, PCBs,dieldrin and trans-nonachlor, but with no significantdifferences in concentrations between Hayward andNewark (P > 0.05).  相似文献   

14.
土壤和底泥中砷、铬、锰测定的前处理技术   总被引:6,自引:0,他引:6  
试验了土壤和底泥中砷的前处理技术,其目的是能对土壤、底泥中砷、铬、锰在一次前处理中制备成试液,比色法分析。试验表明,用H2SO4-H3PO4-H2O2进行前处理是可行的。方法简单、挥发酸雾少,用标准参考物质检验证明,分解完全,数据准确,有粒较好一致性。  相似文献   

15.
This paper presents the chemical speciation and retention behavior of chromium (Cr), nickel (Ni), and cadmium (Cd) prior to and after the electrokinetic remediation in glacial till soil. The speciation of the metals was predicted using the chemical speciation program MINEQL+. The simulations were performed for single-contaminant with only Cr(VI) or Ni, and multi-contaminants consisting of: (1) Cr(VI), Ni, and Cd; (2) Cr(III), Ni and Cd; (3) Cr(VI), Cr(III), Ni and Cd; (4) Cr(VI), Ni, and Cd with reducing agents; and (5) Cr(III), Ni, and Cd with oxidizing agent (Mn). The results showed that the speciation and distribution of cationic metals [Ni, Cd, and Cr(III)] in glacial till soil remain unaffected or slightly affected during electrokinetics. This is attributed to the high pH buffering capacity of the glacial till, leading the metals to precipitate in the soil prior to and after electrokinetics. This study showed that during electrokinetics, Cr(VI) existed as anionic complex and migrated towards the anode and the migration is maximum in case of a single-contaminant system. The study also showed that near the anode in the absence of any reducing and oxidizing agent, Cr(VI) mostly adsorbed, and some of Cr(VI) reduced to Cr(III) and migrated towards the cathode and finally precipitated due to high pH conditions. Ni and Cd remain adsorbed or precipitated due to the high pH conditions throughout the soil. Among the reducing agents, the sulfide had significant effect on the migration of metals compared to ferrous ions. While in the presence of oxidizing agent (Mn), no noticeable Cr(VI) was found in the soil sample indicating the reduction of Cr(VI) to Cr(III) and the predominance of reducing conditions due to the presence of naturally occurring iron in the glacial till soil. Overall, this study provides a reasonable explanation of the speciation and distribution of chromium, nickel and cadmium during the electrokinetic remediation of glacial till soil.  相似文献   

16.
We evaluated exposure of aquatic biota to lead (Pb), zinc (Zn), and cadmium (Cd) in streams draining a Pb-mining district in southeast Missouri. Samples of plant biomass (detritus, periphyton, and filamentous algae), invertebrates (snails, crayfish, and riffle benthos), and two taxa of fish were collected from seven sites closest to mining areas (mining sites), four sites further downstream from mining (downstream sites), and eight reference sites in fall 2001. Samples of plant biomass from mining sites had highest metal concentrations, with means 10- to 60-times greater than those for reference sites. Mean metal concentrations in over 90% of samples of plant biomass from mining sites were significantly greater than those from reference sites. Mean concentrations of Pb, Zn, and Cd in most invertebrate samples from mining sites, and mean Pb concentrations in most fish samples from mining sites, were also significantly greater than those from reference sites. Concentrations of all three metals were lower in samples from downstream sites, but several samples of plant biomass from downstream sites had metal concentrations significantly greater than those from reference sites. Analysis of supplemental samples collected in the fall of 2002, a year of above-average stream discharge, had lower Pb concentrations and higher Cd concentrations than samples collected in 2001, near the end of a multi-year drought. Concentrations of Pb measured in fish and invertebrates collected from mining sites during 2001 and 2002 were similar to those measured at nearby sites in the 1970s, during the early years of mining in the Viburnum Trend. Results of this study demonstrate that long-term Pb mining activity in southeast Missouri has resulted in significantly elevated concentrations of Pb, Cd, and Zn in biota of receiving streams, compared to biota of similar streams without direct influence of mining. Our results also demonstrate that metal exposure in the study area differed significantly among sample types, habitats, and years, and that these factors should be carefully considered in the design of biomonitoring studies.  相似文献   

17.
18.
The present study demonstrates comparison of Cr accumulatingpotential by the plants of Najas indica Cham. (submerged),Vallisneria spiralis L. (rooted submerged) and Alternanthera sessilis R. Br. (rooted emergent) under repeatedmetal exposure and its effect on chlorophyll and protein concentrations. These plants were treated with different concentrations of Cr under repeated exposure in controlled laboratory conditions to assess the maximum metal accumulationpotential. The plants of V. spiralis accumulated significantly high amount of Cr under laboratory conditions incomparison to N. indica and A. sessilis. The maximumaccumulation of 1378, 458 and 201 g g-1 dw Cr was found in the leaves of V. spiralis, N. indica and A. sessilis, respectively at 8 mg L-1 after 9 day of Cr exposure. These plants have shown a decrease in chlorophyll andprotein concentrations with increase in Cr concentrations. In view of high accumulation of Cr in V. spiralis, the plantswere treated with different concentrations of tannery effluent collected from Common Effluent Treatment Plant, Unnao (UP). Theplants of V. spiralis treated with 100% tannery wastewatershowed the maximum accumulation (57.5 g g-1 dw) of Cr in the roots after 10 days of exposure. The plants were foundeffective in removing Cr from solution and tannery effluent.  相似文献   

19.
一起河流砷污染事故的处置与监测分析   总被引:2,自引:1,他引:1  
介绍了大沙河砷污染事故的处置和监测分析。多介质排查监测摸清了污染的范围和程度,为治理工作提供了科学依据,污染治理措施有效控制了污染的扩散;监测数据表明,治理措施将水中砷污染物沉降至河床使污染水质达标排放。吸附了大量砷化合物的底泥被清理并进一步处置,多介质跟踪监测应持续进行直至不存在潜在危害。  相似文献   

20.
日本核泄漏事故引发的核危机为人类安全和平地利用核能又一次敲响了警钟.核事故应急工作作为减小核电站危害环境和公众安全的最后屏障,将起到重要的作用,必须做好相关的准备和响应工作.核应急辐射环境监测工作是核应急工作的重要组成部分,在对核应急辐射环境监测进行准备和响应时主要遵循实用性、适用性和适度性并兼顾常规和应急监测的“平战...  相似文献   

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