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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.
Material Disposal Area G is the primary low-levelradioactive waste disposal site at Los Alamos NationalLaboratory, New Mexico, and is adjacent to Pueblo of SanIldefonso lands. Pueblo residents and Los Alamos scientists areconcerned about radiological doses resulting from uptake of AreaG radionuclides by mule deer (Odocoileus hemionus) andRocky Mountain elk (Cervus elaphus), then consumption ofdeer and elk meat by humans. Tissue samples were collected fromdeer and elk accidentally killed near Area G and were analyzedfor 3H, 90Sr, total U, 238Pu, 239, 240Pu,241Am, and 137Cs. These data were used to estimatehuman doses based on meat consumption of 23 kg y-1. Humandoses were also modeled using RESRAD, and dose rates to deer andelk were estimated with a screening model. Dose estimates tohumans from tissue consumption were 2.9 × 10-3 mSv y-1and 1.6 × 10-3 mSv y-1 from deer and elk, respectively,and RESRAD dose estimates were of the same order of magnitude. Estimated dose rates to deer and elk were 2.1 × 10-4 mGyd-1 and 4.7 × 10-4 mGy d-1, respectively. Allestimated doses were significantly less than established exposurelimits or guidelines.  相似文献   

12.
Metal concentrations in deciduous tree leaves from urban areas in Poland   总被引:1,自引:0,他引:1  
Accumulation of metals in deciduous tree foliage fromurban areas in western-south Poland was monitored duringthe vegetation season of 2000 year. Concentrations of Al,Ba, Ca, Cd, Cr, Cu, Fe, Mg, Mn, Ni, Pb, Sr, Ti and Znwere measured in birch, willow, linden and maple leavesusing the ICP-AES method. Seasonal variations of metalconcentrations and their relations with sampling sitewere investigated. The most dynamic accumulation of Al,Cd, Cr, Ni and Pb was observed for examined species. Thehighest differences in element concentrations forinvestigated sites were found for Ba, Cd, Mn and Ni.Interelement correlations were investigated. In allfoliar samples synergistic relationships between Al–Crand Ca-Sr were found. Statistically significant negativecorrelations were observed only for Cd and Ti in birch leaves.  相似文献   

13.
The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ 15N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ 15N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ 15N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ 15N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas, the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ 15N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R 2 = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ 15N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ 15N of Spartina relates with the integrated, watershed-sea nitrogen inputs.  相似文献   

14.
We grew leek (Allium porrum) in soils of two shooting ranges heavily contaminated with heavy metals in the towns of Zuchwil and Oberuzwil in Switzerland as a bioassay to test theactivity of arbuscular mycorrhizal (AM) fungi in these soils.Soil samples were taken from (1) front of the shooting house(HOUSE), (2) the area between house and target (FIELD) and (3) the berm (BACKSTOP). Samples of Ribwort plantain (Plantagolanceolata) growing naturally within the shooting ranges werealso collected and the colonization of its roots by mycorrhizalfungi was measured. The number of AM spores in the soils wassignificantly reduced concomitant with the increase in thedegree of soil contamination with metals. In Zuchwil,mycorrhizal fungi equally colonized roots of Ribwort plantainsampled from BACKSTOP and HOUSE. In Oberuzwil, however, plantsfrom BACKSTOP had lower colonization when compared with thosesampled from HOUSE. Colonization of leek was strongly reducedin the BACKSTOP soil of Zuchwil and slightly reduced in theBACKSTOP soil of Oberuzwil when compared with plants grown inrespective HOUSE soil. Concentrations of Cd, Cr, Cu, Ni, Pb andZn in the leaves of leek grown in the BACKSTOP soil was withinthe range considered toxic for human consumption. This pointsto the high degree of bio-availability of these metal in thesesoils. Significant decrease in the number of mycorrhizal sporesin the BACKSTOP soils in Zuchwil and the low colonization ofleek roots grown in these soils point to possible changes inthe species diversity of mycorrhizal fungi in these soils.  相似文献   

15.
Concentrations of 13 radionuclides (137Cs, 129I, 60Co, 152Eu, 90Sr, 99Tc, 241Am, 238Pu, 239,249Pu, 234U, 235U, 236U, 238U were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test (1965–1971), and we tested the null hypotheses that there were no differences in radionuclide concentrations between Amchitka and the reference site (Kiska) and there were no differences among species. The only radionuclides where composite samples were above the Minimum Detectable Activity (MDA) were 137Cs, 241Am, 239,249Pu, 234U, 235U, 236U, and 238U. Green sea urchin (Strongylocentrotus polyacanthus), giant chiton (Cryptochiton stelleri), plate limpets (Tectura scutum) and giant Pacific octopus (Enteroctopus dofleini) were only tested for 137Cs; octopus was the only species with detectable levels of 137Cs (0.262 ± 0.029 Bq/kg, wet weight). Only rock jingle (Pododesmus macroschisma), blue mussel (Mytilus trossulus) and horse mussel (Modiolus modiolus) were analyzed for the actinides. There were no interspecific differences in 241Am and 239,240Pu, and almost no samples above the MDA for 238Pu and 236U. Horse mussels had significantly higher concentrations of 234U (0.844 ± 0.804 Bq/kg) and 238U (0.730 ± 0.646) than the other species (both isotopes are naturally occurring). There were no differences in actinide concentrations between Amchitka and Kiska. In general, radionuclides in invertebrates from Amchitka were similar to those from uncontaminated sites in the Northern Hemisphere, and below those from the contaminated Irish Sea. There is a clear research need for authors to report the concentrations of radionuclides by species, rather than simply as ‘shellfish’, for comparative purposes in determining geographical patterns, understanding possible effects, and for estimating risk to humans from consuming different biota.  相似文献   

16.
Kelp may be useful as a bioindicator because they are primary producers that are eaten by higher trophic level organisms, including people and livestock. Often when kelp or other algae species are used as bioindicators, the whole organism is homogenized. However, some kelp can be over 25 m long from their holdfast to the tip of the blade, making it important to understand how contaminant levels vary throughout the plant. We compared the levels of arsenic, cadmium, chromium, lead, manganese, mercury and selenium in five different parts of the kelp Alaria nana to examine the variability of metal distribution. To be useful as a bioindicator, it is critical to know whether levels are constant throughout the kelp, or which part is the highest accumulator. Kelp were collected on Adak Island in the Aleutian Chain of Alaska from the Adak Harbor and Clam Cove, which opens onto the Bering Sea. In addition to determining if the levels differ in different parts of the kelp, we wanted to determine whether there were locational or size-related differences. Regression models indicated that between 14% and 43% of the variation in the levels of arsenic, cadmium, chromium, manganese, mercury, and selenium was explained by total length, part of the plant, and location (but not for lead). The main contributors to variability were length (for arsenic and selenium), location (mercury), and part of the plant (for arsenic, cadmium, chromium and manganese). The higher levels of selenium occurred at Clam Cove, while mercury was higher at the harbor. Where there was a significant difference among parts, the holdfast had the highest levels, although the differences were not great. These data indicate that consistency should be applied in selecting the part of kelp (and the length) to be used as a bioindicator. While any part of Alaria could be collected for some metals, for arsenic, cadmium, chromium, and manganese a conversion should be made among parts. In the Aleutians the holdfast can be perennial while the blade, whipped to pieces by winter wave action, is regrown each year. Thus the holdfast may be used for longer-term exposure for arsenic, cadmium, chromium and manganese, while the blade can be used for short-term exposure for all metals. Cadmium, lead and selenium were at levels that suggest that predators, including people, may be at risk from consuming Alaria. More attention should be devoted to heavy metal levels in kelp and other algae from Adak, particularly where they may play a role in a subsistence diets.  相似文献   

17.
Biological damage to sensitive aquatic ecosystems is among the most recognisable, deleterious effects of acidic deposition. We compiled a large spatial database of over 2000 waterbodies across southeastern Canada from various federal, provincial and academic sources. Data for zooplankton, fish, macroinvertebrate (benthos) and loon species richness and occurrence were used to construct statistical models for lakes with varying pH, dissolved organic carbon content and lake size. pH changes, as described and predicted using the Integrated Assessment Model (Lam et al., 1998; Jeffries et al., 2000), were based on the range of emission reductions set forth in the Canada/US Air Quality Agreement (AQA). The scenarios tested include 1983, 1990, 1994 and 2010 sulphate deposition levels. Biotic models were developed for five regions in southeastern Canada (Algoma, Muskoka, and Sudbury, Ontario, southcentral Québec, and Kejimkujik, Nova Scotia) using regression tree, multiple linear regression and logistic regression analyses to make predictions about recovery after emission reductions. The analyses produced different indicator species in different regions, although some species showed consistent trends across regions. Generally, the greatest predicted recovery occurred during the final phase of emission reductions between 1994 and 2010 across all taxonomic groups and regions. The Ontario regions, on average, were predicted to recover to a greater extent than either southcentral Québec or the Kejimkujik area of Nova Scotia. Our results reconfirm that pH 5.5–6.0 is an important threshold below which damage to aquatic biota will remain a major local and regional environmental problem. This damage to biodiversity across trophic levels will persist well into the future if no further reductions in sulphate deposition are implemented.  相似文献   

18.
Nitrogen (N) pollution is a growing concern in forests of the greater Sierra Nevada, which lie downwind of the highly populated and agricultural Central Valley. Nitrogen content of Letharia vulpina tissue was analyzed from 38 sites using total Kjeldahl analysis to provide a preliminary assessment of N deposition patterns. Collections were co-located with plots where epiphytic macrolichen communities are used for estimating ammonia (NH3) deposition. Tissue N ranged from 0.6% to 2.11% with the highest values occurring in the southwestern Sierra Nevada (range: 1.38 to 2.11). Tissue N at 17 plots was elevated, as defined by a threshold concentration of 1.03%. Stepwise regression was used to determine the best predictors of tissue N from among a variety of environmental variables. The best model consisted only of longitude (r 2 = 0.64), which was reflected in the geographic distribution of tissue values: the southwestern Sierra Nevada, the high Sierras near the Tahoe Basin, and the Modoc Plateau, are three apparent N hotspots arranged along the tilted north–south axis of the study area. Withholding longitude and latitude, the best regression model suggested that NH3 estimates and annual number of wetdays interactively affect N accumulation (r 2 = 0.61; % N ∼ NH3 + wetdays + (NH3 × wetdays)). We did not expect perfect correspondence between tissue values and NH3 estimates since other N pollutants also accumulate in the lichen thallus. Additionally, other factors potentially affecting N content, such as growth rate and leaching, were not given full account.  相似文献   

19.
Pesticide applications to agricultural lands in California, USA, are reported to a central data base, while data on water and sediment quality are collected by a number of monitoring programs. Data from both sources are geo-referenced, allowing spatial analysis of relationships between pesticide application rates and the chemical and biological condition of water bodies. This study collected data from 12 watersheds, selected to represent a range of pesticide usage. Water quality parameters were measured during six surveys of stream sites receiving runoff from the selected watershed areas. This study had three objectives: to evaluate the usefulness of pesticide application data in selecting regional monitoring sites, to provide information for generating and testing hypotheses about pesticide fate and effects, and to determine whether in-stream nitrate concentration was a useful surrogate indicator for regional monitoring of toxic substances. Significant correlations were observed between pesticide application rates and in-stream pesticide concentrations (p < 0.05) and toxicity (p < 0.10). In-stream nitrate concentrations were not significantly correlated with either the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.30). Neither total watershed area nor the area in which pesticide usage was reported correlated significantly with the amount of pesticides applied, in-stream pesticide concentrations, or in-stream toxicity (all p > 0.14). In-stream pesticide concentrations and effects were more closely related to the intensity of pesticide use than to the area under cultivation.  相似文献   

20.
With increasing interest in assessing the health or well-being ofcommunities and ecosystems, birds are being used asbioindicators. Coloniallynesting species breed mainly in coastal areas that are alsopreferred for humandevelopment, exposing the birds to various pollutants. Inthis paper concentrations of heavy metal and selenium in the feathers ofHerring Gulls(Larus argentatus) nesting in several colonies fromMassachusetts toDelaware are reported. There were significant differencesamong colonies forall metals, with metal concentrations being two to nearly fivetimes higher atsome colonies than others. Selenium showed the leastdifference, and cadmium showed the greatest difference among sites. Concentrations of lead werehighest at Pralls Island; mercury was highest at Shinnecock,Huckleberry andHarvey, and manganese was highest at Captree.  相似文献   

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