Impact of urbanization level on urban air quality: a case of fine particles (PM(2.5)) in Chinese cities.

Science.gov (United States)

Han, Lijian; Zhou, Weiqi; Li, Weifeng; Li, Li

2014-11-01

We examined and compared PM2.5 concentrations in urban and the surrounding regions, and further investigated the impact of urbanization on urban PM2.5 concentrations at the Chinese prefectures. Annual PM2.5 concentrations in most prefectures were greater than 10 μg/m(3), the air quality guideline of the World Health Organization. Those prefectures were mainly distributed along the east coast and southeast of Sichuan province; The urban PM2.5 concentrations ( [Formula: see text] ) in 85 cities were greater than (>10 μg/m(3)) those in the surrounding area. Those cities were mainly located in the Beijing-Sichuan and Shanghai-Guangxi belts. In addition, [Formula: see text] was less than (urban population (R(2) = 0.99, P urban second industry fraction (R(2) = 0.71, P urbanization had considerable impact on PM2.5 concentrations. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Comprehensive Quantitative Evaluation of New Sustainable Urbanization Level in 20 Chinese Urban Agglomerations

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Cong Xu

2016-01-01

Full Text Available On 16 March 2014, the State Council of China launched its first urbanization planning initiative dubbed “National New Urbanization Planning (2014–2020” (NNUP. NNUP put forward 20 urban agglomerations and a sustainable development approach aiming to transform traditional Chinese urbanization to sustainable new urbanization. This study quantitatively evaluates the level of sustainability of the present new urbanization process in 20 Chinese urban agglomerations and provides some positive suggestions for the achievement of sustainable new urbanization. A three-level index system which is based on six fundamental elements in a city and a Full Permutation Polygon Synthetic Indicator evaluation method are adopted. The results show that China is undergoing a new urbanization process with a low level of sustainability and there are many problems remaining from traditional urbanization processes. There exists a polarized phenomenon in the urbanization of 20 urban agglomerations. Based on their own development patterns, the 20 urban agglomerations can be divided into seven categories. Every category has its own development characteristics. The analyses also show that waste of water resources, abuse of land resources, and air pollution are three big problems that are closely linked to traditional Chinese urbanization processes. To achieve sustainable new urbanization in China, four relevant suggestions and comments have been provided.

KPI-Driven Methodology for Urban Renovation at District Level. Sustainable Strategic Urban Planning

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Cristina Criado

2018-03-01

Full Text Available Sustainable urban renovation is characterized by multiple factors (e.g., technical, socio-economic, environmental and ethical perspectives, different spatial scales and a number of administrative structures that should address the evaluation of alternative scenarios or solutions. This defines a complex decision problem that includes different stakeholders where several aspects need to be considered simultaneously. In spite of the knowledge and experiences during the recent years, there is a need of methods that lead the decision-making processes. In response, a methodology based on a KPI-driven approach for urban renovation at district level is proposed in the European Smart City project CITyFiED. The methodology is a procedure with the energy efficiency as main pillar and the local authorities as client. It is composed of seven phases that ensures an effective dialogue among all the stakeholders, aiming to understand the objectives and needs of the city to deliver a set of customized Strategies for Sustainable Urban Renovation. In order to provide guidance and quantitative criteria, three levels of indicators are integrated into the approach: City Level Indicators (L1 at city & district level, Project Level KPIs (L2, and Impact Assessment Indicators at city level (L3.

The nexus between urbanization and PM2.5 related mortality in China.

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Liu, Miaomiao; Huang, Yining; Jin, Zhou; Ma, Zongwei; Liu, Xingyu; Zhang, Bing; Liu, Yang; Yu, Yang; Wang, Jinnan; Bi, Jun; Kinney, Patrick L

2017-08-01

The launch of China's new national urbanization plan, coupled with increasing concerns about air pollution, calls for better understandings of the nexus between urbanization and the air pollution-related health. Based on refined estimates of PM 2.5 related mortality in China, we developed an Urbanization-Excess Deaths Elasticity (U-EDE) indicator to measure the marginal PM 2.5 related mortality caused by urbanization. We then applied statistical models to estimate U-EDE and examined the modification effects of income on U-EDE. Urbanization in China between 2004 and 2012 led to increased PM 2.5 related mortality. A 1% increase in urbanization was associated with a 0.32%, 0.14%, and 0.50% increase in PM 2.5 related mortality of lung cancer, stroke, and ischemic heart disease. U-EDEs were modified by income with an inverted U curve, i.e., lower marginal impacts at the lowest and highest income levels. In addition, we projected the future U-EDE trend of China as a whole and found that China had experienced the peak of U-EDE and entered the second half of the inverted U-shaped curve. In the near future, national average U-EDE in China will decline along with the improvement of income level if no dramatic changes happen. However, the decreased U-EDE only implies that marginal PM 2.5 -related mortality brought by urbanization would decrease in China. Total health damage of urbanization will keep going up in the predictable future because the U-EDE is always positive. Copyright © 2017 Elsevier Ltd. All rights reserved.

Urban stormwater - greywater management system for sustainable urban water management at sub-watershed level

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Singh Arora, Amarpreet

2017-11-01

Urban water management involves urban water supply (import, treatment and distribution of water), urban wastewater management (collection, treatment and disposal of urban sewage) and urban storm water management. Declining groundwater tables, polluted and declining sources of water, water scarcity in urban areas, unsatisfactory urban water supply and sanitation situation, pollution of receiving water bodies (including the ground water), and urban floods have become the concerns and issues of sustainable urban water management. This paper proposes a model for urban stormwater and sewage management which addresses these concerns and issues of sustainable urban water management. This model proposes segregation of the sewage into black water and greywater, and urban sub-watershed level stormwater-greywater management systems. During dry weather this system will be handling only the greywater and making the latter available as reclaimed water for reuse in place of the fresh water supply. During wet weather, the system will be taking care of (collection and treatment) both the storm water and the greywater, and the excess of the treated water will be disposed off through groundwater recharging. Application of this model in the Patiala city, Punjab, INDIA for selected urban sub-watersheds has been tried. Information and background data required for the conceptualization and design of the sub-watershed level urban stormwater-greywater management system was collected and the system has been designed for one of the sub-watersheds in the Patiala city. In this paper, the model for sustainable urban water management and the design of the Sub-watershed level Urban Stormwater-Greywater Management System are described.

Assessment of daytime outdoor comfort levels in and outside the urban area of Glasgow, UK.

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Krüger, Eduardo; Drach, Patricia; Emmanuel, Rohinton; Corbella, Oscar

2013-07-01

To understand thermal preferences and to define a preliminary outdoor comfort range for the local population of Glasgow, UK, an extensive series of measurements and surveys was carried out during 19 monitoring campaigns from winter through summer 2011 at six different monitoring points in pedestrian areas of downtown Glasgow. For data collection, a Davis Vantage Pro2 weather station equipped with temperature and humidity sensors, cup anemometer with wind vane, silicon pyranometer and globe thermometer was employed. Predictions of the outdoor thermal index PET (physiologically equivalent temperature) correlated closely to the actual thermal votes of respondents. Using concurrent measurements from a second Davis Vantage Pro2 weather station placed in a rural setting approximately 15 km from the urban area, comparisons were drawn with regard to daytime thermal comfort levels and urban-rural temperature differences (∆T(u-r)) for the various sites. The urban sites exhibited a consistent lower level of thermal discomfort during daytime. No discernible effect of urban form attributes in terms of the sky-view factor were observed on ∆Tu-r or on the relative difference of the adjusted predicted percentage of dissatisfied (PPD*).

Individual exposure to NO2 in relation to spatial and temporal exposure indices in Stockholm, Sweden: the INDEX study.

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Tom Bellander

Full Text Available Epidemiology studies of health effects from air pollution, as well as impact assessments, typically rely on ambient monitoring data or modelled residential levels. The relationship between these and personal exposure is not clear. To investigate personal exposure to NO(2 and its relationship with other exposure metrics and time-activity patterns in a randomly selected sample of healthy working adults (20-59 years living and working in Stockholm. Personal exposure to NO(2 was measured with diffusive samplers in sample of 247 individuals. The 7-day average personal exposure was 14.3 µg/m(3 and 12.5 µg/m(3 for the study population and the inhabitants of Stockholm County, respectively. The personal exposure was significantly lower than the urban background level (20.3 µg/m(3. In the univariate analyses the most influential determinants of individual exposure were long-term high-resolution dispersion-modelled levels of NO(2 outdoors at home and work, and concurrent NO(2 levels measured at a rural location, difference between those measured at an urban background and rural location and difference between those measured in busy street and at an urban background location, explaining 20, 16, 1, 2 and 4% (R(2 of the 7-day personal NO(2 variation, respectively. A regression model including these variables explained 38% of the variation in personal NO(2 exposure. We found a small improvement by adding time-activity variables to the latter model (R(2 = 0.44. The results adds credibility primarily to long-term epidemiology studies that utilise long-term indices of NO(2 exposure at home or work, but also indicates that such studies may still suffer from exposure misclassification and dilution of any true effects. In contrast, urban background levels of NO(2 are poorly related to individual exposure.

The effect of long-range air mass transport pathways on PM10 and NO2 concentrations at urban and rural background sites in Ireland: Quantification using clustering techniques.

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Donnelly, Aoife A; Broderick, Brian M; Misstear, Bruce D

2015-01-01

The specific aims of this paper are to: (i) quantify the effects of various long range transport pathways nitrogen dioxide (NO2) and particulate matter with diameter less than 10μm (PM10) concentrations in Ireland and identify air mass movement corridors which may lead to incidences poor air quality for application in forecasting; (ii) compare the effects of such pathways at various sites; (iii) assess pathways associated with a period of decreased air quality in Ireland. The origin of and the regions traversed by an air mass 96h prior to reaching a receptor is modelled and k-means clustering is applied to create air-mass groups. Significant differences in air pollution levels were found between air mass cluster types at urban and rural sites. It was found that easterly or recirculated air masses lead to higher NO2 and PM10 levels with average NO2 levels varying between 124% and 239% of the seasonal mean and average PM10 levels varying between 103% and 199% of the seasonal mean at urban and rural sites. Easterly air masses are more frequent during winter months leading to higher overall concentrations. The span in relative concentrations between air mass clusters is highest at the rural site indicating that regional factors are controlling concentration levels. The methods used in this paper could be applied to assist in modelling and forecasting air quality based on long range transport pathways and forecast meteorology without the requirement for detailed emissions data over a large regional domain or the use of computationally demanding modelling techniques.

A Comprehensive Quantitative Evaluation of New Sustainable Urbanization Level in 20 Chinese Urban Agglomerations

OpenAIRE

Cong Xu; Shixin Wang; Yi Zhou; Litao Wang; Wenliang Liu

2016-01-01

On 16 March 2014, the State Council of China launched its first urbanization planning initiative dubbed “National New Urbanization Planning (2014–2020)” (NNUP). NNUP put forward 20 urban agglomerations and a sustainable development approach aiming to transform traditional Chinese urbanization to sustainable new urbanization. This study quantitatively evaluates the level of sustainability of the present new urbanization process in 20 Chinese urban agglomerations and provides some positive sugg...

Observations of ClNO2 and PANs in a mid-continental urban environment

Science.gov (United States)

Furgeson, A.; Mielke, L.; Osthoff, H. D.

2010-12-01

Nitrogen oxides play many important roles in regional air quality, for example, through the catalytic photochemical production of O3 involving NOx (=NO+NO2), which in urban environments is primarily of anthropogenic origin. NOx can be converted to reservoir species, such as peroxyacyl nitrates (PANs), or removed from the atmosphere, mainly by conversion to HNO3, which is removed predominantly through heterogeneous uptake and dry deposition. The main HNO3 production pathways are reaction of NO2 with OH during the day and heterogeneous reactions involving N2O5 at night. It has been known for some time that heterogeneous N2O5 hydrolysis (i.e., N2O5 + H2O → 2HNO3) competes with ClNO2 formation (i.e., N2O5 + Cl- → ClNO2 + NO3-) on chloride containing aerosol, but the latter reaction is believed to be only of significance in marine and coastal environments. Formation of ClNO2 is significant as it reduces the rate of nocturnal NOx removal and activates chlorine by releasing highly reactive Cl atoms following ClNO2 photolysis after sunrise. Recent field measurements by Thornton and coworkers have shown the efficient formation of ClNO2 in mid-continental air at a distance greater than 1,000 km from the nearest coastline. In this presentation, measurements of peroxyacyl nitrates and ClNO2 by chemical ionization mass spectrometry (CIMS) on the rooftop of a 6-story building in Calgary, Alberta, Canada, are described. The CIMS was operated in negative ion mode and equipped with a heated inlet to dissociate PANs to NO2 and the corresponding PA radicals, which are converted to the respective carboxylate anions using iodide reagent ion. ClNO2 was monitored as the cluster ion (ClNO2)I- at m/z 208 and 210. The CIMS was calibrated for peroxyacyl nitrates using a newly developed photolysis source, which was also used to deliver an internal standard during the measurement intensive. Measurements took place during spring and fall of 2010. During spring, we observed in excess of 200

Interferences of commercial NO2 instruments in the urban atmosphere and in a smog chamber

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J. Kleffmann

2012-01-01

Full Text Available Reliable measurements of atmospheric trace gases are necessary for both, a better understanding of the chemical processes occurring in the atmosphere, and for the validation of model predictions. Nitrogen dioxide (NO2 is a toxic gas and is thus a regulated air pollutant. Besides, it is of major importance for the oxidation capacity of the atmosphere and plays a pivotal role in the formation of ozone and acid precipitation. Detection of NO2 is a difficult task since many of the different commercial techniques used are affected by interferences. The chemiluminescence instruments that are used for indirect NO2 detection in monitoring networks and smog chambers use either molybdenum or photolytic converters and are affected by either positive (NOy or negative interferences (radical formation in the photolytic converter. Erroneous conclusions on NO2 can be drawn if these interferences are not taken into consideration. In the present study, NO2 measurements in the urban atmosphere, in a road traffic tunnel and in a smog-chamber using different commercial techniques, i.e. chemiluminescence instruments with molybdenum or photolytic converters, a Luminol based instrument and a new NO2-LOPAP, were compared with spectroscopic techniques, i.e. DOAS and FTIR. Interferences of the different instruments observed during atmospheric measurements were partly characterised in more detail in the smog chamber experiments. Whereas all the commercial instruments showed strong interferences, excellent agreement was obtained between a new NO2-LOPAP instrument and the FTIR technique for the measurements performed in the smog chamber.

A statistical downscaling approach for roadside NO2 concentrations: Application to a WRF-Chem study for Berlin

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Kuik, Friderike; Lauer, Axel; von Schneidemesser, Erika; Butler, Tim

2017-04-01

Many European cities continue to struggle with meeting the European air quality limits for NO2. In Berlin, Germany, most of the exceedances in NO2 recorded at monitoring sites near busy roads can be largely attributed to emissions from traffic. In order to assess the impact of changes in traffic emissions on air quality at policy relevant scales, we combine the regional atmosphere-chemistry transport model WRF-Chem at a resolution of 1kmx1km with a statistical downscaling approach. Here, we build on the recently published study evaluating the performance of a WRF-Chem setup in representing observed urban background NO2 concentrations from Kuik et al. (2016) and extend this setup by developing and testing an approach to statistically downscale simulated urban background NO2 concentrations to street level. The approach uses a multilinear regression model to relate roadside NO2 concentrations observed with the municipal monitoring network with observed NO2 concentrations at urban background sites and observed traffic counts. For this, the urban background NO2 concentrations are decomposed into a long term, a synoptic and a diurnal component using the Kolmogorov-Zurbenko filtering method. We estimate the coefficients of the regression model for five different roadside stations in Berlin representing different street types. In a next step we combine the coefficients with simulated urban background concentrations and observed traffic counts, in order to estimate roadside NO2 concentrations based on the results obtained with WRF-Chem at the five selected stations. In a third step, we extrapolate the NO2 concentrations to all major roads in Berlin. The latter is based on available data for Berlin of daily mean traffic counts, diurnal and weekly cycles of traffic as well as simulated urban background NO2 concentrations. We evaluate the NO2 concentrations estimated with this method at street level for Berlin with additional observational data from stationary measurements and

NO2 and Cancer Incidence in Saudi Arabia

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Khalid Al-Ahmadi

2013-11-01

Full Text Available Air pollution exposure has been shown to be associated with an increased risk of specific cancers. This study investigated whether the number and incidence of the most common cancers in Saudi Arabia were associated with urban air pollution exposure, specifically NO2. Overall, high model goodness of fit (GOF was observed in the Eastern, Riyadh and Makkah regions. The significant coefficients of determination (r2 were higher at the regional level (r2 = 0.32–0.71, weaker at the governorate level (r2 = 0.03–0.43, and declined slightly at the city level (r2 = 0.17–0.33, suggesting that an increased aggregated spatial level increased the explained variability and the model GOF. However, the low GOF at the lowest spatial level suggests that additional variation remains unexplained. At different spatial levels, associations between NO2 concentration and the most common cancers were marginally improved in geographically weighted regression (GWR analysis, which explained both global and local heterogeneity and variations in cancer incidence. High coefficients of determination were observed between NO2 concentration and lung and breast cancer incidences, followed by prostate, bladder, cervical and ovarian cancers, confirming results from other studies. These results could be improved using individual explanatory variables such as environmental, demographic, behavioral, socio-economic, and genetic risk factors.

Ways to Say No: Refusal Skill Strategies among Urban Adolescents

Science.gov (United States)

Nichols, Tracy R.; Graber, Julia A.; Brooks-Gunn, Jeanne; Botvin, Gilbert J.

2006-01-01

Objectives: To examine associations among adolescents' generated verbal strategies (ie, Simple No, Declarative Statements, Excuse, Alternatives) and underlying nonverbal assertiveness in 2 refusal situations: smoking and shoplifting. Methods: Sixth-grade urban minority students (N = 454) participated in videotaped role-play assessments of peer…

Ground-level ozone in the Pearl River Delta and the roles of VOC and NO(x) in its production.

Science.gov (United States)

Shao, Min; Zhang, Yuanhang; Zeng, Limin; Tang, Xiaoyan; Zhang, Jing; Zhong, Liuju; Wang, Boguang

2009-01-01

In many regions of China, very rapid economic growth has been accompanied by air pollution caused by vehicle emissions. In one of these regions, the Pearl River Delta, the variations of ground-level ozone and its precursors were investigated. Overall, the ambient concentrations of NO(2) increased quickly between 1995 and 1996, but then slightly decreased due to stringent nitrogen oxide (NO(x)) emission controls. Nonetheless, ambient NO(2) levels in the Pearl River Delta remained high. The regional average concentrations of volatile organic compounds (VOCs) were 290 ppbC in summer and 190 ppbC in autumn. Local emissions and long-distance transportation of pollutants play important roles in the regional distribution of VOCs. Ambient O(3) production is significant in urban areas and also downwind of cities. The relative incremental reactivities (RIRs), determined by an observation-based model, showed that ground-level ozone formation in the Guangzhou urban area is generally limited by the concentrations of VOCs, but there are also measurable impacts of NO(x).

Examination of the Relationship between Urban Air Pollution and Urban Planning Decisions in Cigli Case, Izmir (Turkey

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Nur Sinem Ozcan

2016-06-01

Full Text Available The air pollution problem remains, although significant improvements have been seen in urban air quality over the last years. Despite the size and variety of studies on urban air pollution, the usage of spatial statistics has been extremely limited. This study aims to show that the spatial statistic techniques can well be used to examine and explain the air pollution levels in urban areas. The data for the sulphur dioxide (SO2 and nitrogen dioxide (NO2 concentrations are measures using passive diffusion tubes at the 67 monitoring sites in the district of Çiğli (Izmir, which are selected through a spatial systematic sampling process. The tubes were exposed for a 2-week period in August 2015. For the determination of the level of clustering for high values and low values of SO2 and NO2 concentrations, Getis-Ord G* local statistics are calculated. There are five points with high values of SO2 surrounded by low values, three points of NO2, where the results are statistically significant at the 0.10 level. The findings indicate that the presence of the industrial zone, the form of fossil fuels (coal or natural gas used in heating, and topography are the strong determinants urban air pollution.

No Evidence of Association between Childhood Urban Environment and Cortical Thinning in Psychotic Disorder.

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Frissen, Aleida; van Os, Jim; Habets, Petra; Gronenschild, Ed; Marcelis, Machteld

2017-01-01

The alterations in cortical morphology, such as cortical thinning, observed in psychotic disorder, may be the outcome of interacting genetic and environmental effects. It has been suggested that urban upbringing may represent a proxy environmental effect impacting cortical thickness (CT). Therefore, the current study examined whether the association between group as a proxy genetic variable (patients with psychotic disorder [high genetic risk], healthy siblings of patients [intermediate risk] and healthy control subjects [average risk]) and CT was conditional on different levels of the childhood urban environment and whether this was sex-dependent. T1-weighted MRI scans were acquired from 89 patients with a psychotic disorder, 95 non-psychotic siblings of patients with psychotic disorder and 87 healthy control subjects. Freesurfer software was used to measure CT. Developmental urban exposure was classified as low, medium, and high, reflecting the population density and the number of moves between birth and the 15th birthday, using data from the Dutch Central Bureau of Statistics and the equivalent database in Belgium. Multilevel regression analyses were used to examine the association between group, sex, and urban upbringing (as well as their interactions) and cortical CT as the dependent variable. CT was significantly smaller in the patient group compared to the controls (B = -0.043, p <0.001), but not in the siblings compared to the controls (B = -0.013, p = 0.31). There was no main effect of developmental urbanicity on CT (B = 0.001, p = 0.91). Neither the three-way group × urbanicity × sex interaction (χ2 = 3.73, p = 0.16), nor the two-way group × urbanicity interaction was significant (χ2 = 0.51, p = 0.77). The negative association between (familial risk for) psychotic disorder and CT was not moderated by developmental urbanicity, suggesting that reduced CT is not the outcome of familial sensitivity to the proxy environmental factor 'urban upbringing'.

No Evidence of Association between Childhood Urban Environment and Cortical Thinning in Psychotic Disorder.

Directory of Open Access Journals (Sweden)

Aleida Frissen

Full Text Available The alterations in cortical morphology, such as cortical thinning, observed in psychotic disorder, may be the outcome of interacting genetic and environmental effects. It has been suggested that urban upbringing may represent a proxy environmental effect impacting cortical thickness (CT. Therefore, the current study examined whether the association between group as a proxy genetic variable (patients with psychotic disorder [high genetic risk], healthy siblings of patients [intermediate risk] and healthy control subjects [average risk] and CT was conditional on different levels of the childhood urban environment and whether this was sex-dependent.T1-weighted MRI scans were acquired from 89 patients with a psychotic disorder, 95 non-psychotic siblings of patients with psychotic disorder and 87 healthy control subjects. Freesurfer software was used to measure CT. Developmental urban exposure was classified as low, medium, and high, reflecting the population density and the number of moves between birth and the 15th birthday, using data from the Dutch Central Bureau of Statistics and the equivalent database in Belgium. Multilevel regression analyses were used to examine the association between group, sex, and urban upbringing (as well as their interactions and cortical CT as the dependent variable.CT was significantly smaller in the patient group compared to the controls (B = -0.043, p <0.001, but not in the siblings compared to the controls (B = -0.013, p = 0.31. There was no main effect of developmental urbanicity on CT (B = 0.001, p = 0.91. Neither the three-way group × urbanicity × sex interaction (χ2 = 3.73, p = 0.16, nor the two-way group × urbanicity interaction was significant (χ2 = 0.51, p = 0.77.The negative association between (familial risk for psychotic disorder and CT was not moderated by developmental urbanicity, suggesting that reduced CT is not the outcome of familial sensitivity to the proxy environmental factor 'urban

A Comparative Land Use-Based Analysis of Noise Pollution Levels in Selected Urban Centers of Nigeria.

Science.gov (United States)

Baloye, David O; Palamuleni, Lobina G

2015-09-29

Growth in the commercialization, mobility and urbanization of human settlements across the globe has greatly exposed world urban population to potentially harmful noise levels. The situation is more disturbing in developing countries like Nigeria, where there are no sacrosanct noise laws and regulations. This study characterized noise pollution levels in Ibadan and Ile-Ife, two urban areas of Southwestern Nigeria that have experienced significant increases in population and land use activities. Eight hundred noise measurements, taken at 20 different positions in the morning, afternoon, and evening of carefully selected weekdays, in each urban area, were used for this study. Findings put the average noise levels in the urban centers at between 53 dB(A) and 89 dB (A), a far cry from the World Health Organization (WHO) permissible limits in all the land use types, with highest noise pollution levels recorded for transportation, commercial, residential and educational land use types. The result of the one-way ANOVA test carried out on the dependent variable noise and fixed factor land use types reveals a statistically significant mean noise levels across the study area (F(3,34) = 15.13, p = 0.000). The study underscores noise pollution monitoring and the urgent need to control urban noise pollution with appropriate and effective policies.

Collecting standardized urban health indicator data at an individual level for school-aged children living in urban areas: methods from EURO-URHIS 2.

Science.gov (United States)

Pope, D; Katreniak, Z; Guha, J; Puzzolo, E; Higgerson, J; Steels, S; Woode-Owusu, M; Bruce, N; Birt, Christopher A; Ameijden, E van; Verma, A

2017-05-01

Measuring health and its determinants in urban populations is essential to effectively develop public health policies maximizing health gain within this context. Adolescents are important in this regard given the origins of leading causes of morbidity and mortality develop pre-adulthood. Comprehensive, accurate and comparable information on adolescent urban health indicators from heterogeneous urban contexts is an important challenge. EURO-URHIS 2 aimed to develop standardized tools and methodologies collecting data from adolescents across heterogenous European urban contexts. Questionnaires were developed including (i) comprehensive assessment of urban health indicators from 7 pre-defined domains, (ii) use of previously validated questions from a literature review and other European surveys, (iii) translation/back-translation into European languages and (iv) piloting. Urban area-specific data collection methodologies were established through literature review, consultation and piloting. School-based surveys of 14-16-year olds (400-800 per urban area) were conducted in 13 European countries (33 urban areas). Participation rates were high (80-100%) for students from schools taking part in the surveys from all urban areas, and data quality was generally good (low rates of missing/spoiled data). Overall, 13 850 questionnaires were collected, coded and entered for EURO-URHIS 2. Dissemination included production of urban area health profiles (allowing benchmarking for a number of important public health indicators in young people) and use of visualization tools as part of the EURO-URHIS 2 project. EURO-URHIS 2 has developed standardized survey tools and methodologies for assessing key measures of health and its determinants in adolescents from heterogenous urban contexts and demonstrated the utility of this data to public health practitioners and policy makers. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association

‘New urbanism' or metropolitan-level centralization?

DEFF Research Database (Denmark)

Næss, Petter

2011-01-01

Based on a study in Copenhagen Metropolitan Area, this paper compares the influences of macro-level and micro-level urban form characteristics on the respondents' traveling distance by car on weekdays. The Copenhagen study shows that metropolitan-scale urban structural variables generally exert...... stronger influences than neighborhood-scale built environment characteristics on the amount of car travel. In particular, the location of the residence relative to the main city center of the metropolitan region shows a strong effect. Some local scale variables often mentioned in the literature...

Elevated Levels of Herbivory in Urban Landscapes: Are Declines in Tree Health More Than an Edge Effect?

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Fiona J. Christie

2005-06-01

Full Text Available Urbanization is one of the most extreme and rapidly growing anthropogenic pressures on the natural world. Urban development has led to substantial fragmentation of areas of natural habitat, resulting in significant impacts on biodiversity and disruptions to ecological processes. We investigated the levels of leaf damage caused by invertebrates in a dominant canopy species in urban remnants in a highly fragmented urban landscape in Sydney, Australia, by assessing the frequency and extent of chewing and surface damage of leaves in urban remnants compared to the edges and interiors of continuous areas of vegetation. Although no difference was detected in the frequency of leaves showing signs of damage at small, edge, and interior sites, small sites suffered significantly greater levels of leaf damage than did interior sites. Trees at edge sites showed intermediate levels of damage, suggesting that edge effects alone are not the cause of higher levels of herbivory. These findings are the first to demonstrate the effects of urbanization on invertebrate damage in dominant trees at coarse scales. This is consistent with hypotheses predicting that changes in species composition through urban fragmentation affect ecological interactions.

Field observations of regional and urban impacts on NO2, ozone, UVB, and nitrate radical production rates in the Phoenix air basin

International Nuclear Information System (INIS)

Gaffney, J.S.; Marley, N.A.; Drayton, P.J.; Doskey, P.V.; Kotamarthi, V.R.; Cunningham, M.M.; Baird, J.C.; Dintaman, J.; Hart, H.L.

2002-01-01

In the May and June of 1998, field measurements were taken at a site near the Usery Pass Recreation Area, ∼27 miles from the downtown Phoenix area, overlooking Phoenix and Mesa, Arizona. This site was selected to examine the impacts of the Phoenix urban plume on the Usery Pass Recreation Area and surrounding regions. Data were obtained for ultraviolet-B (UVB) radiation, nitrogen dioxide (NO 2 ), peroxyacetyl nitrate (PAN), ozone (O 3 ), and carbon monoxide (CO). Nocturnal plumes of NO 2 (in tens of ppb), observed near midnight, were correlated with CO and anti-correlated with O 3 . This behavior was consistent with the titration of locally generated NO by boundary layer O 3 to form the nighttime NO 2 plumes that were subsequently transported into the Usery Pass Recreation area. Nitrate radical (NO 3 ) production rates were calculated to be very high on the edges of these nocturnal plumes. Examination of O 3 and PAN data also indicates that Phoenix is being affected by long-range transport of pollutants from the Los Angeles to San Diego areas. A regional smoke episode was observed in May, accompanied by a decrease in UVB of factor of two and a decrease in O 3 and an increase in methyl chloride. Low level back trajectories and chemical evidence confirm that the smoke event originated in northern Mexico and that the reduced O 3 levels observed at Usery Pass could be partially due to reduced photolysis rates caused by carbonaceous soot aerosols transported in the smoke plume. The results are discussed with regard to potential effects of local pollution transport from the Phoenix air basin as well as an assessment of the contributions from long-range transport of pollutants to the background levels in the Phoenix-Usery Pass area. (author)

CO2 emissions, real output, energy consumption, trade, urbanization and financial development: testing the EKC hypothesis for the USA.

Science.gov (United States)

Dogan, Eyup; Turkekul, Berna

2016-01-01

This study aims to investigate the relationship between carbon dioxide (CO2) emissions, energy consumption, real output (GDP), the square of real output (GDP(2)), trade openness, urbanization, and financial development in the USA for the period 1960-2010. The bounds testing for cointegration indicates that the analyzed variables are cointegrated. In the long run, energy consumption and urbanization increase environmental degradation while financial development has no effect on it, and trade leads to environmental improvements. In addition, this study does not support the validity of the environmental Kuznets curve (EKC) hypothesis for the USA because real output leads to environmental improvements while GDP(2) increases the levels of gas emissions. The results from the Granger causality test show that there is bidirectional causality between CO2 and GDP, CO2 and energy consumption, CO2 and urbanization, GDP and urbanization, and GDP and trade openness while no causality is determined between CO2 and trade openness, and gas emissions and financial development. In addition, we have enough evidence to support one-way causality running from GDP to energy consumption, from financial development to output, and from urbanization to financial development. In light of the long-run estimates and the Granger causality analysis, the US government should take into account the importance of trade openness, urbanization, and financial development in controlling for the levels of GDP and pollution. Moreover, it should be noted that the development of efficient energy policies likely contributes to lower CO2 emissions without harming real output.

Influence of urban vegetation on air pollution and noise exposure - A case study in Gothenburg, Sweden.

Science.gov (United States)

Klingberg, Jenny; Broberg, Malin; Strandberg, Bo; Thorsson, Pontus; Pleijel, Håkan

2017-12-01

Air pollution levels (NO 2 , PAHs, O 3 ) were investigated, before (BLE) and after (ALE) leaf emergence, in the urban landscape of Gothenburg, Sweden. The aims were to study the 1) spatial and temporal variation in pollution levels between urban green areas, 2) effect of urban vegetation on air pollution levels at the same distance from a major emission source (traffic route), 3) improvement of urban air quality in urban parks compared to adjacent sites near traffic, 4) correlation between air pollution and noise in a park. O 3 varied little over the urban landscape. NO 2 varied strongly and was higher in situations strongly influenced by traffic. Four PAH variables were included: total PAH, total particle-bound PAH, the quantitatively important gaseous phenanthrene and the highly toxic particle-bound benzo(a)pyrene. The variation of PAHs was similar to NO 2 , but for certain PAHs the difference between highly and less polluted sites was larger than for NO 2 . At a vegetated site, NO 2 and particulate PAH levels were lower than at a non-vegetated site at a certain distance from a busy traffic route. This effect was significantly larger ALE compared to BLE for NO 2 , indicating green leaf area to be highly significant factor for air quality improvement. For particulate PAHs, the effect was similar BLE and ALE, indicating that tree bark and branches also could be an important factor in reducing air pollution. Parks represented considerably cleaner local environments (park effect), which is likely to be a consequence of both a dilution (distance effect) and deposition. Noise and air pollution (NO 2 and PAH) levels were strongly correlated. Comparison of noise levels BLE and ALE also showed that the presence of leaves significantly reduced noise levels. Our results are evidence that urban green spaces are beneficial for urban environmental quality, which is important to consider in urban planning. Copyright © 2017 Elsevier B.V. All rights reserved.

Spatial variations in nitrogen dioxide concentrations in urban Ljubljana, Slovenia

Directory of Open Access Journals (Sweden)

Vintar Mally Katja

2015-09-01

Full Text Available Ambient nitrogen dioxide (NO2 concentrations are regularly measured at only two monitoring stations in the city centre of Ljubljana, and such scanty data are inadequate for drawing conclusions about spatial patterns of pollution within the city, or to decide on effective measures to further improve air quality. In order to determine the spatial distribution of NO2 concentrations in different types of urban space in Ljubljana, two measuring campaigns throughout the city were carried out, during the summer of 2013 and during the winter of 2014. The main source of NO2 in Ljubljana is road transport. Accordingly, three types of urban space have been identified (urban background, open space along roads, and street canyon, and their NO2 pollution level was measured using Palmes diffusive samplers at a total of 108 measuring spots. This article analyses the results of both measuring campaigns and compares the pollution levels of different types of urban space.

Behavior of trace NO/sub X/ species in the nighttime urban atmosphere

International Nuclear Information System (INIS)

Killus, J.P.; Whitten, G.Z.

1985-01-01

Three trace NO/sub X/ species--HONO, NO 3 , and N 2 O 5 --may play important roles in urban smog formation. Alternative mechanisms for these species have recently been proposed. This report presents a brief analysis of simulation results indicating that the traditional chemistry for these species can still explain the results of some recent observational studies

Air pollution and decreased semen quality: A comparative study of Chongqing urban and rural areas

International Nuclear Information System (INIS)

Zhou, Niya; Cui, Zhihong; Yang, Sanming; Han, Xue; Chen, Gangcai; Zhou, Ziyuan; Zhai, Chongzhi; Ma, Mingfu; Li, Lianbing; Cai, Min; Li, Yafei; Ao, Lin; Shu, Weiqun; Liu, Jinyi; Cao, Jia

2014-01-01

To investigate the association and effects of air pollution level on male semen quality in urban and rural areas, this study examines the outdoor concentrations of particulate matter (PM 10 ), sulfur dioxide (SO 2 ), nitrous dioxide (NO 2 ) and semen quality outcomes for 1346 volunteers in both urban and rural areas in Chongqing, China. We found the urban area has a higher pollution level than the rural area, contrasted with better semen quality in the rural residents, especially for sperm morphology and computer assistant semen analysis (CASA) motility parameters. A multivariate linear regression analysis demonstrates that concentrations of PM 10 , SO 2 , and NO 2 significantly and negatively are associated with normal sperm morphology percentage (P  10 , SO 2 , and NO 2 in urban ambient air may account for worse semen quality in urban males. - Highlights: • We investigate the distributions of PM 10 , SO 2 and NO 2 in urban and rural areas in Chongqing, China. • We explore the associations of air pollution and male semen quality. • The concentrations of PM 10 , SO 2 , and NO 2 are significantly higher in urban areas. • Median values of some semen quality parameters in rural male were higher than urban male. • PM 10 , SO 2 , and NO 2 were negatively associated with semen quality parameters. - Air pollution is higher in the urban area while there is better semen quality in rural males. Polluted air may thus account for worse semen quality in urban males

Relationships between Changes in Urban Characteristics and Air Quality in East Asia from 2000 to 2010.

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Larkin, Andrew; van Donkelaar, Aaron; Geddes, Jeffrey A; Martin, Randall V; Hystad, Perry

2016-09-06

Characteristics of urban areas, such as density and compactness, are associated with local air pollution concentrations. The potential for altering air pollution through changing urban characteristics, however, is less certain, especially for expanding cities within the developing world. We examined changes in urban characteristics from 2000 to 2010 for 830 cities in East Asia to evaluate associations with changes in nitrogen dioxide (NO2) and fine particulate matter (PM2.5) air pollution. Urban areas were stratified by population size into small (100 000-250 000), medium, (250 000-1 000 000), and large (>1 000 000). Multivariate regression models including urban baseline characteristics, meteorological variables, and change in urban characteristics explained 37%, 49%, and 54% of the change in NO2 and 29%, 34%, and 37% of the change in PM2.5 for small, medium and large cities, respectively. Change in lights at night strongly predicted change in NO2 and PM2.5, while urban area expansion was strongly associated with NO2 but not PM2.5. Important differences between changes in urban characteristics and pollutant levels were observed by city size, especially NO2. Overall, changes in urban characteristics had a greater impact on NO2 and PM2.5 change than baseline characteristics, suggesting urban design and land use policies can have substantial impacts on local air pollution levels.

Assessing environmental inequalities in ambient air pollution across urban Australia.

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Knibbs, Luke D; Barnett, Adrian G

2015-04-01

Identifying inequalities in air pollution levels across population groups can help address environmental justice concerns. We were interested in assessing these inequalities across major urban areas in Australia. We used a land-use regression model to predict ambient nitrogen dioxide (NO2) levels and sought the best socio-economic and population predictor variables. We used a generalised least squares model that accounted for spatial correlation in NO2 levels to examine the associations between the variables. We found that the best model included the index of economic resources (IER) score as a non-linear variable and the percentage of non-Indigenous persons as a linear variable. NO2 levels decreased with increasing IER scores (higher scores indicate less disadvantage) in almost all major urban areas, and NO2 also decreased slightly as the percentage of non-Indigenous persons increased. However, the magnitude of differences in NO2 levels was small and may not translate into substantive differences in health. Copyright © 2015 Elsevier Ltd. All rights reserved.

Porphyrin pattern and methemoglobin levels in Columba livia applied to assess toxicological risk by air pollution in urban areas.

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Sicolo, Matteo; Tringali, Maria; Orsi, Federica; Santagostino, Angela

2009-11-01

The study has explored two conservative biomarkers, porphyrin pattern in guano and methemoglobin levels in blood of Columba livia, in order to assay their potential use for monitoring toxic effects induced by exposure to urban air pollution. Fieldwork was conducted between October 2003 and June 2005 in the city of Milan, Italy, by sampling the pigeons in different areas almost twice a week. Six air contaminants, CO, PM10, NO(2), O(3), SO(2), and C(6)H(6), plus polycyclic aromatic hydrocarbons (PAHs) in fine particles, temperature, and UV index, were considered. Protoporphyrins from pigeon excreta sampled outdoors were always higher than in indoor animals, particularly in winter. A positive correlation (p urban air showed significant differences from season to season but only in summer and autumn did the outdoor pigeons show higher values than indoor animals. In summer, a regression model with a positive correlation between O(3) and benzene was determined (p urban air pollution as well as for detecting complex interactions between contaminants in the urban air pollutant mixture was discussed.

Developing micro-level urban ecosystem indicators for sustainability assessment

Energy Technology Data Exchange (ETDEWEB)

Dizdaroglu, Didem, E-mail: dizdaroglu@bilkent.edu.tr

2015-09-15

Sustainability assessment is increasingly being viewed as an important tool to aid in the shift towards sustainable urban ecosystems. An urban ecosystem is a dynamic system and requires regular monitoring and assessment through a set of relevant indicators. An indicator is a parameter which provides information about the state of the environment by producing a quantitative value. Indicator-based sustainability assessment needs to be considered on all spatial scales to provide efficient information of urban ecosystem sustainability. The detailed data is necessary to assess environmental change in urban ecosystems at local scale and easily transfer this information to the national and global scales. This paper proposes a set of key micro-level urban ecosystem indicators for monitoring the sustainability of residential developments. The proposed indicator framework measures the sustainability performance of urban ecosystem in 3 main categories including: natural environment, built environment, and socio-economic environment which are made up of 9 sub-categories, consisting of 23 indicators. This paper also describes theoretical foundations for the selection of each indicator with reference to the literature [Turkish] Highlights: • As the impacts of environmental problems have multi-scale characteristics, sustainability assessment needs to be considered on all scales. • The detailed data is necessary to assess local environmental change in urban ecosystems to provide insights into the national and global scales. • This paper proposes a set of key micro-level urban ecosystem indicators for monitoring the sustainability of residential developments. • This paper also describes theoretical foundations for the selection of each indicator with reference to the literature.

Urban NH3 levels and sources in six major Spanish cities.

Science.gov (United States)

Reche, Cristina; Viana, Mar; Karanasiou, Angeliki; Cusack, Michael; Alastuey, Andrés; Artiñano, Begoña; Revuelta, M Aranzazu; López-Mahía, Purificación; Blanco-Heras, Gustavo; Rodríguez, Sergio; Sánchez de la Campa, Ana M; Fernández-Camacho, Rocío; González-Castanedo, Yolanda; Mantilla, Enrique; Tang, Y Sim; Querol, Xavier

2015-01-01

A detailed spatial and temporal assessment of urban NH3 levels and potential emission sources was made with passive samplers in six major Spanish cities (Barcelona, Madrid, A Coruña, Huelva, Santa Cruz de Tenerife and Valencia). Measurements were conducted during two different periods (winter-autumn and spring-summer) in each city. Barcelona showed the clearest spatial pattern, with the highest concentrations in the old city centre, an area characterised by a high population density and a dense urban architecture. The variability in NH3 concentrations did not follow a common seasonal pattern across the different cities. The relationship of urban NH3 with SO2 and NOX allowed concluding on the causes responsible for the variations in NH3 levels between measurement periods observed in Barcelona, Huelva and Madrid. However, the factors governing the variations in A Coruña, Valencia and Santa Cruz de Tenerife are still not fully understood. This study identified a broad variability in NH3 concentrations at the city-scale, and it confirms that NH3 sources in Spanish urban environments are vehicular traffic, biological sources (e.g. garbage containers), wastewater treatment plants, solid waste treatment plants and industry. The importance of NH3 monitoring in urban environments relies on its role as a precursor of secondary inorganic species and therefore PMX. Further research should be addressed in order to establish criteria to develop and implement mitigation strategies for cities, and to include urban NH3 sources in the emission inventories. Copyright © 2014 Elsevier Ltd. All rights reserved.

High resolution spatio-temporal mapping of NO2 pollution for estimating personal exposures of the Dutch population

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Soenario, Ivan; Helbich, Marco; Schmitz, Oliver; Strak, Maciek; Hoek, Gerard; Karssenberg, Derek

2017-04-01

Air pollution has been associated with adverse health effects (e.g., cardiovascular and respiration diseases) in the urban environments. Therefore, the assessment of people's exposure to air pollution is central in epidemiological studies. The estimation of exposures on an individual level can be done by combining location information across space and over time with spatio-temporal data on air pollution concentrations. When detailed information on peoples' space-time paths (e.g. commuting patterns calculated by means of spatial routing algorithms or tracked through GPS) and peoples' major activity locations (e.g. home location, work location) are available, it is possible to calculate more precise personal exposure levels depending on peoples' individual space-time mobility patterns. This requires air pollution values not only at a high level of spatial accuracy and high temporal granularity but such data also needs to be available on a nation-wide scale. As current data is seriously limited in this respect, we introduce a novel data set of NO2 levels across the Netherlands. The provided NO2 concentrations are accessible on hourly timestamps on a 5 meter grid cell resolution for weekdays and weekends, and each month of the year. We modeled a single Land Use Regression model using a five year average of NO2 data from the Dutch NO2 measurement network consisting of N=46 sampling locations distributed over the country. Predictor variables for this model were selected in a data-driven manner using an Elastic Net and Best Subset Selection procedure from 70 candidate predictors including traffic, industry, infrastructure and population-based variables. Subsequently, to model NO2 for each time scale (hour, week, month), the LUR coefficients were fitted using the NO2 data, aggregated per time scale. Model validation was grounded on independent data collected in an ad hoc measurement campaign. Our results show a considerable difference in urban concentrations between

Levels of teen dating violence and substance use in an urban emergency department.

Science.gov (United States)

Mason, Michael J; Campbell, Leah; Zaharakis, Nikola; Foster, Robin; Richards, Susan

2014-01-01

Teen dating violence (TDV) is associated with multiple sequelae including substance use. The objective of this study was to determine the prevalence and association between levels of dating violence and substance use among urban adolescents presenting at a pediatric emergency department (ED). As part of standard practice, 282 adolescents were screened for relationship status, producing 135 dating violence screens. Scales from the Revised Conflict Tactics Scale and the Youth Risk Behavior Survey were used to capture variables of interest. Logistic regression was performed to test the influence of levels of dating violence on substance use, while controlling for gender, race, age, sexual orientation, and psychiatric symptoms. Over one-quarter of those teens (27.3%) within a current relationship reported experiencing any dating violence, 26.1% experienced psychological violence, and 11.9% experienced physical violence. Teens experiencing psychological violence were at twice the risk for any substance use (alcohol, marijuana, and tobacco use) and specifically for alcohol and marijuana, whereas no increased risk was found for teens experiencing physical violence. This study contributes to the understanding of TDV within the context of high-risk, urban adolescents presenting at a pediatric ED. Identifying levels of TDV and understanding the association with substance use can provide an important foundation for prevention and early intervention for urban youth.

The AOTF-Based NO2 Camera

Science.gov (United States)

Dekemper, E.; Fussen, D.; Vanhellemont, F.; Vanhamel, J.; Pieroux, D.; Berkenbosch, S.

2017-12-01

In an urban environment, nitrogen dioxide is emitted by a multitude of static and moving point sources (cars, industry, power plants, heating systems,…). Air quality models generally rely on a limited number of monitoring stations which do not capture the whole pattern, neither allow for full validation. So far, there has been a lack of instrument capable of measuring NO2 fields with the necessary spatio-temporal resolution above major point sources (power plants), or more extended ones (cities). We have developed a new type of passive remote sensing instrument aiming at the measurement of 2-D distributions of NO2 slant column densities (SCDs) with a high spatial (meters) and temporal (minutes) resolution. The measurement principle has some similarities with the popular filter-based SO2 camera (used in volcanic and industrial sulfur emissions monitoring) as it relies on spectral images taken at wavelengths where the molecule absorption cross section is different. But contrary to the SO2 camera, the spectral selection is performed by an acousto-optical tunable filter (AOTF) capable of resolving the target molecule's spectral features. A first prototype was successfully tested with the plume of a coal-firing power plant in Romania, revealing the dynamics of the formation of NO2 in the early plume. A lighter version of the NO2 camera is now being tested on other targets, such as oil refineries and urban air masses.

City Level of Income and Urbanization and Availability of Food Stores and Food Service Places in China.

Science.gov (United States)

Liao, Chunxiao; Tan, Yayun; Wu, Chaoqun; Wang, Shengfeng; Yu, Canqing; Cao, Weihua; Gao, Wenjing; Lv, Jun; Li, Liming

2016-01-01

The contribution of unhealthy dietary patterns to the epidemic of obesity has been well recognized. Differences in availability of foods may have an important influence on individual eating behaviors and health disparities. This study examined the availability of food stores and food service places by city characteristics on city level of income and urbanization. The cross-sectional survey was comprised of two parts: (1) an on-site observation to measure availability of food stores and food service places in 12 cities of China; (2) an in-store survey to determine the presence of fresh/frozen vegetables or fruits in all food stores. Trained investigators walked all the streets/roads within study tracts to identify all the food outlets. An observational survey questionnaire was used in all food stores to determine the presence of fresh/frozen vegetables or fruits. Urbanization index was determined for each city using a principal components factor analysis. City level of income and urbanization and numbers of each type of food stores and food service places were examined using negative binomial regression models. Large-sized supermarkets and specialty retailers had higher number of fresh/frozen vegetables or fruits sold compared to small/medium-sized markets. High-income versus low-income, high urbanized versus low urbanized areas had significantly more large-sized supermarkets and fewer small/medium-sized markets. In terms of restaurants, high urbanized cities had more western fast food restaurants and no statistically significant difference in the relative availability of any type of restaurants was found between high- and low-income areas. The findings suggested food environment disparities did exist in different cities of China.

City Level of Income and Urbanization and Availability of Food Stores and Food Service Places in China.

Directory of Open Access Journals (Sweden)

Chunxiao Liao

Full Text Available The contribution of unhealthy dietary patterns to the epidemic of obesity has been well recognized. Differences in availability of foods may have an important influence on individual eating behaviors and health disparities. This study examined the availability of food stores and food service places by city characteristics on city level of income and urbanization.The cross-sectional survey was comprised of two parts: (1 an on-site observation to measure availability of food stores and food service places in 12 cities of China; (2 an in-store survey to determine the presence of fresh/frozen vegetables or fruits in all food stores. Trained investigators walked all the streets/roads within study tracts to identify all the food outlets. An observational survey questionnaire was used in all food stores to determine the presence of fresh/frozen vegetables or fruits. Urbanization index was determined for each city using a principal components factor analysis. City level of income and urbanization and numbers of each type of food stores and food service places were examined using negative binomial regression models.Large-sized supermarkets and specialty retailers had higher number of fresh/frozen vegetables or fruits sold compared to small/medium-sized markets. High-income versus low-income, high urbanized versus low urbanized areas had significantly more large-sized supermarkets and fewer small/medium-sized markets. In terms of restaurants, high urbanized cities had more western fast food restaurants and no statistically significant difference in the relative availability of any type of restaurants was found between high- and low-income areas.The findings suggested food environment disparities did exist in different cities of China.

City Level of Income and Urbanization and Availability of Food Stores and Food Service Places in China

Science.gov (United States)

Liao, Chunxiao; Tan, Yayun; Wu, Chaoqun; Wang, Shengfeng; Yu, Canqing; Cao, Weihua; Gao, Wenjing; Lv, Jun; Li, Liming

2016-01-01

Objective The contribution of unhealthy dietary patterns to the epidemic of obesity has been well recognized. Differences in availability of foods may have an important influence on individual eating behaviors and health disparities. This study examined the availability of food stores and food service places by city characteristics on city level of income and urbanization. Methods The cross-sectional survey was comprised of two parts: (1) an on-site observation to measure availability of food stores and food service places in 12 cities of China; (2) an in-store survey to determine the presence of fresh/frozen vegetables or fruits in all food stores. Trained investigators walked all the streets/roads within study tracts to identify all the food outlets. An observational survey questionnaire was used in all food stores to determine the presence of fresh/frozen vegetables or fruits. Urbanization index was determined for each city using a principal components factor analysis. City level of income and urbanization and numbers of each type of food stores and food service places were examined using negative binomial regression models. Results Large-sized supermarkets and specialty retailers had higher number of fresh/frozen vegetables or fruits sold compared to small/medium-sized markets. High-income versus low-income, high urbanized versus low urbanized areas had significantly more large-sized supermarkets and fewer small/medium-sized markets. In terms of restaurants, high urbanized cities had more western fast food restaurants and no statistically significant difference in the relative availability of any type of restaurants was found between high- and low-income areas. Conclusions The findings suggested food environment disparities did exist in different cities of China. PMID:26938866

A high-resolution and observationally constrained OMI NO2 satellite retrieval

International Nuclear Information System (INIS)

Goldberg, Daniel L.; Lamsal, Lok N.; Loughner, Christopher P.

2017-01-01

Here, this work presents a new high-resolution NO 2 dataset derived from the NASA Ozone Monitoring Instrument (OMI) NO 2 version 3.0 retrieval that can be used to estimate surface-level concentrations. The standard NASA product uses NO 2 vertical profile shape factors from a 1.25° × 1° (~110 km × 110 km) resolution Global Model Initiative (GMI) model simulation to calculate air mass factors, a critical value used to determine observed tropospheric NO 2 vertical columns. To better estimate vertical profile shape factors, we use a high-resolution (1.33 km × 1.33 km) Community Multi-scale Air Quality (CMAQ) model simulation constrained by in situ aircraft observations to recalculate tropospheric air mass factors and tropospheric NO 2 vertical columns during summertime in the eastern US. In this new product, OMI NO 2 tropospheric columns increase by up to 160% in city centers and decrease by 20–50 % in the rural areas outside of urban areas when compared to the operational NASA product. Our new product shows much better agreement with the Pandora NO 2 and Airborne Compact Atmospheric Mapper (ACAM) NO 2 spectrometer measurements acquired during the DISCOVER-AQ Maryland field campaign. Furthermore, the correlation between our satellite product and EPA NO 2 monitors in urban areas has improved dramatically: r 2 = 0.60 in the new product vs. r 2 = 0.39 in the operational product, signifying that this new product is a better indicator of surface concentrations than the operational product. Our work emphasizes the need to use both high-resolution and high-fidelity models in order to recalculate satellite data in areas with large spatial heterogeneities in NO x emissions. Although the current work is focused on the eastern US, the methodology developed in this work can be applied to other world regions to produce high-quality region-specific NO 2 satellite retrievals.

Adsorption of NO{sub 2} on carbon aerosols particles at the low ppb-level

Energy Technology Data Exchange (ETDEWEB)

Kalberer, M.; Ammann, M.; Baltensperger, U.; Gaeggeler, H.W. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

1997-09-01

The adsorption of NO{sub 2} at the low ppb-level (3-40 ppb) on carbon aerosol particles was investigated. A sticking coefficient of about 2.10{sup -4} was found, similar to that in previous studies using radioactively labeled {sup 13}NO{sub 2}. (author) 2 figs., 2 refs.

The Effects of Urban Sprawl on Birds at Multiple Levels of Biological Organization

Directory of Open Access Journals (Sweden)

Robert Blair

2004-12-01

Full Text Available Urban sprawl affects the environment in myriad ways and at multiple levels of biological organization. In this paper I explore the effects of sprawl on native bird communities by comparing the occurrence of birds along gradients of urban land use in southwestern Ohio and northern California and by examining patterns at the individual, species, community, landscape, and continental levels. I do this by assessing the distribution and abundance of all bird species occupying sites of differing land-use intensity in Ohio and California. Additionally, I conducted predation experiments using artificial nests, tracked the nest fate of American Robins and Northern Cardinals, and assessed land cover in these sites. At the individual level, predation on artificial nests decreased with urbanization; however, this trend was not reflected in the nesting success of robins and cardinals, which did not increase with urbanization. At the species level, sprawl affected local patterns of extinction and invasion; the density of different species peaked at different levels of urbanization. At the community level, species richness and diversity peaked at moderate levels of urbanization, and the number of low-nesting species and of species with multiple broods increased with urbanization. The community-level results may reflect both the species-level patterns of local extinction and invasion as well as broader landscape-level patterns. At the landscape level, a linear combination of spatial heterogeneity and density of woody patches accurately predicted both species richness and Shannon Diversity. At the continental level, local extinction of endemic species, followed by the invasion of ubiquitous weedy species, leads to faunal homogenization between ecoregions.

The Next-generation Berkeley High Resolution NO2 (BEHR NO2) Retrieval: Design and Preliminary Emissions Constraints

Science.gov (United States)

Laughner, J.; Cohen, R. C.

2017-12-01

Recent work has identified a number of assumptions made in NO2 retrievals that lead to biases in the retrieved NO2 column density. These include the treatment of the surface as an isotropic reflector, the absence of lightning NO2 in high resolution a priori profiles, and the use of monthly averaged a priori profiles. We present a new release of the Berkeley High Resolution (BEHR) OMI NO2 retrieval based on the new NASA Standard Product (version 3) that addresses these assumptions by: accounting for surface anisotropy by using a BRDF albedo product, using an updated method of regridding NO2 data, and revised NO2 a priori profiles that better account for lightning NO2 and daily variation in the profile shape. We quantify the effect these changes have on the retrieved NO2 column densities and the resultant impact these updates have on constraints of urban NOx emissions for select cities throughout the United States.

Comparison of land use regression models for NO2 based on routine and campaign monitoring data from an urban area of Japan.

Science.gov (United States)

Kashima, Saori; Yorifuji, Takashi; Sawada, Norie; Nakaya, Tomoki; Eboshida, Akira

2018-08-01

Typically, land use regression (LUR) models have been developed using campaign monitoring data rather than routine monitoring data. However, the latter have advantages such as low cost and long-term coverage. Based on the idea that LUR models representing regional differences in air pollution and regional road structures are optimal, the objective of this study was to evaluate the validity of LUR models for nitrogen dioxide (NO 2 ) based on routine and campaign monitoring data obtained from an urban area. We selected the city of Suita in Osaka (Japan). We built a model based on routine monitoring data obtained from all sites (routine-LUR-All), and a model based on campaign monitoring data (campaign-LUR) within the city. Models based on routine monitoring data obtained from background sites (routine-LUR-BS) and based on data obtained from roadside sites (routine-LUR-RS) were also built. The routine LUR models were based on monitoring networks across two prefectures (i.e., Osaka and Hyogo prefectures). We calculated the predictability of the each model. We then compared the predicted NO 2 concentrations from each model with measured annual average NO 2 concentrations from evaluation sites. The routine-LUR-All and routine-LUR-BS models both predicted NO 2 concentrations well: adjusted R 2 =0.68 and 0.76, respectively, and root mean square error=3.4 and 2.1ppb, respectively. The predictions from the routine-LUR-All model were highly correlated with the measured NO 2 concentrations at evaluation sites. Although the predicted NO 2 concentrations from each model were correlated, the LUR models based on routine networks, and particularly those based on all monitoring sites, provided better visual representations of the local road conditions in the city. The present study demonstrated that LUR models based on routine data could estimate local traffic-related air pollution in an urban area. The importance and usefulness of data from routine monitoring networks should be

Physical activity and cardiovascular risk factors among rural and urban groups and rural-to-urban migrants in Peru: a cross-sectional study.

Science.gov (United States)

Masterson Creber, Ruth M; Smeeth, Liam; Gilman, Robert H; Miranda, J Jaime

2010-07-01

To compare physical activity and sedentary behavior patterns of rural-to-urban migrants in Peru versus lifetime rural and urban residents and to determine any associations between low physical activity and four cardiovascular risk factors: obesity (body mass index > 30 kg/m²), systolic and diastolic blood pressure, hypertension, and metabolic syndrome. The PERU MIGRANT (PEru's Rural to Urban MIGRANTs) cross-sectional study was designed to measure physical activity among rural, urban, and rural-to-urban migrants with the International Physical Activity Questionnaire (IPAQ). The World Health Organization (WHO) age-standardized prevalence of low physical activity was 2.2% in lifetime rural residents, 32.2% in rural-to-urban migrants, and 39.2% in lifetime urban residents. The adjusted odds ratios for low physical activity were 21.43 and 32.98 for migrant and urban groups respectively compared to the rural group. The adjusted odds ratio for being obese was 1.94 for those with low physical activity. There was no evidence of an association between low physical activity and blood pressure levels, hypertension, or metabolic syndrome. People living in a rural area had much higher levels of physical activity and lower risk of being overweight and obese compared to those living in an urban area of Lima. Study participants from the same rural area who had migrated to Lima had levels of physical inactivity and obesity similar to those who had always lived in Lima. Interventions aimed at maintaining higher levels of physical activity among rural-to-urban migrants may help reduce the epidemic of obesity in urban cities.

Indoor NO{sub 2} levels in homes with different sources of air pollution - traffic, gas-use, smoking

Energy Technology Data Exchange (ETDEWEB)

Rudnai, P.; Farkas, I.; Bacskai, J.; Sarkany, E. [Bela Johan National Inst. of Hygiene, Budapest (Hungary); Somogyi, J. [Public Health Inst. of County Gyor-Moson-Sopron, Gyor (Hungary)

1993-12-31

Outdoor and indoor levels of NO{sub 2} in and around the homes of 300 children living in different parts of two Hungarian towns, Gyor and Sopron, were measured. Possible sources of NO{sub 2} pollution were assessed by questionnaires. NO{sub 2} levels in homes without any further known sources (like gas use for cooking and/or heating and smoking) varied according to the outdoor levels mainly depending on traffic density. Gas heaters had the strongest influence on the indoor NO{sub 2} levels measured in the children`s bedrooms while gas use for cooking and smoking proved to be the second and third most important source of indoor NO{sub 2} pollution. Different outdoor and indoor NO{sub 2} sources should be taken into account when planning the heating and ventilation systems of new buildings. (author)

Urbanicity Gradients Are Associated with the Household- and Individual-Level Double Burden of Malnutrition in Sub-Saharan Africa.

Science.gov (United States)

Jones, Andrew D; Acharya, Yubraj; Galway, Lindsay P

2016-06-01

The nutrition transition is advancing throughout sub-Saharan Africa (SSA). However, the nutritional risk across urbanicity gradients associated with this transition is not clear. We aimed to determine 1) the extent to which overweight and anemia in women of childbearing age (WCBA) and stunting in preschool-age children (PSC) are spatially correlated within countries of SSA; and 2) the association of urbanicity with the individual-level nutritional double burden (i.e., concurrent overweight and anemia within an individual WCBA), the household-level double burden (i.e., overweight WCBA and stunted PSC in the same household), and the 3 components of these double burdens (i.e., overweight, anemia, and stunting). We used Demographic and Health Surveys (DHS) data for 30 countries in SSA from 2006-2012. We calculated overweight [body mass index (BMI; in kg/m(2)) ≥25] and anemia (hemoglobin concentration urbanicity. We used geolocated DHS data to calculate cluster-level mean population densities and the Moran's I statistic to assess spatial autocorrelation. Cluster-level BMI values and hemoglobin concentrations for WCBA were spatially correlated. The odds of overweight in WCBA were higher in periurban and urban areas than in rural areas (periurban, OR: 1.08; 95% CI: 1.01, 1.16; urban, OR: 1.26; 95% CI: 1.18, 1.36), as were the odds of stunting in PSC in periurban areas (OR: 1.13; 95% CI: 1.06, 1.22). The odds of both double burden conditions were higher in periurban and urban areas than in rural areas (individual-level-periurban, OR: 1.18; 95% CI: 1.05, 1.33; urban, OR: 1.43; 95% CI: 1.27, 1.61; household-level-periurban, OR: 1.24; 95% CI: 1.06, 1.44; urban, OR: 1.24; 95% CI: 1.06, 1.46). Urban and periurban areas in SSA may be particularly vulnerable to the nutritional double burden compared with rural areas. Clearly differentiating urban environments is important for assessing changing patterns of nutritional risk associated with the nutrition transition in SSA. �

Seasonal variability of soil CO2 flux and its carbon isotope composition in Krakow urban area, Southern Poland.

Science.gov (United States)

Jasek, Alina; Zimnoch, Miroslaw; Gorczyca, Zbigniew; Smula, Ewa; Rozanski, Kazimierz

2014-06-01

As urban atmosphere is depleted of (13)CO2, its imprint should be detectable in the local vegetation and therefore in its CO2 respiratory emissions. This work was aimed at characterising strength and isotope signature of CO2 fluxes from soil in urban areas with varying distances from anthropogenic CO2 emissions. The soil CO2 flux and its δ(13)C isotope signature were measured using a chamber method on a monthly basis from July 2009 to May 2012 within the metropolitan area of Krakow, Southern Poland, at two locations representing different levels of anthropogenic influence: a lawn adjacent to a busy street (A) and an urban meadow (B). The small-scale spatial variability of the soil CO2 flux was also investigated at site B. Site B revealed significantly higher summer CO2 fluxes (by approximately 46 %) than site A, but no significant differences were found between their δ(13)CO2 signatures.

Developing micro-level urban ecosystem indicators for sustainability assessment

International Nuclear Information System (INIS)

Dizdaroglu, Didem

2015-01-01

Sustainability assessment is increasingly being viewed as an important tool to aid in the shift towards sustainable urban ecosystems. An urban ecosystem is a dynamic system and requires regular monitoring and assessment through a set of relevant indicators. An indicator is a parameter which provides information about the state of the environment by producing a quantitative value. Indicator-based sustainability assessment needs to be considered on all spatial scales to provide efficient information of urban ecosystem sustainability. The detailed data is necessary to assess environmental change in urban ecosystems at local scale and easily transfer this information to the national and global scales. This paper proposes a set of key micro-level urban ecosystem indicators for monitoring the sustainability of residential developments. The proposed indicator framework measures the sustainability performance of urban ecosystem in 3 main categories including: natural environment, built environment, and socio-economic environment which are made up of 9 sub-categories, consisting of 23 indicators. This paper also describes theoretical foundations for the selection of each indicator with reference to the literature [tr

High prevalence of elevated blood lead levels in both rural and urban Iowa newborns: Spatial patterns and area-level covariates.

Science.gov (United States)

Carrel, Margaret; Zahrieh, David; Young, Sean G; Oleson, Jacob; Ryckman, Kelli K; Wels, Brian; Simmons, Donald L; Saftlas, Audrey

2017-01-01

Lead in maternal blood can cross the placenta and result in elevated blood lead levels in newborns, potentially producing negative effects on neurocognitive function, particularly if combined with childhood lead exposure. Little research exists, however, into the burden of elevated blood lead levels in newborns, or the places and populations in which elevated lead levels are observed in newborns, particularly in rural settings. Using ~2300 dried bloods spots collected within 1-3 days of birth among Iowa newborns, linked with the area of mother's residence at the time of birth, we examine the spatial patterns of elevated (>5 μg/dL) blood lead levels and the ecological-level predictors of elevated blood lead levels. We find that one in five newborns exceed the 5 μg/dL action level set by the US Centers for Disease Control & Prevention (CDC). Bayesian spatial zero inflated regression indicates that elevated blood lead in newborns is associated with areas of increased pre-1940s housing and childbearing-age women with low educational status in both rural and urban settings. No differences in blood lead levels or the proportion of children exceeding 5 μg/dL are observed between urban and rural maternal residence, though a spatial cluster of elevated blood lead is observed in rural counties. These characteristics can guide the recommendation for testing of infants at well-baby appointments in places where risk factors are present, potentially leading to earlier initiation of case management. The findings also suggest that rural populations are at as great of risk of elevated blood lead levels as are urban populations. Analysis of newborn dried blood spots is an important tool for lead poisoning surveillance in newborns and can direct public health efforts towards specific places and populations where lead testing and case management will have the greatest impact.

Urbanization and health in China, thinking at the national, local and individual levels.

Science.gov (United States)

Li, Xinhu; Song, Jinchao; Lin, Tao; Dixon, Jane; Zhang, Guoqin; Ye, Hong

2016-03-08

China has the biggest population in the world, and has been experiencing the largest migration in history, and its rapid urbanization has profound and lasting impacts on local and national public health. Under these conditions, a systems understanding on the correlation among urbanization, environmental change and public health and to devise solutions at national, local and individual levels are in urgent need. In this paper, we provide a comprehensive review of recent studies which have examined the relationship between urbanization, urban environmental changes and human health in China. Based on the review, coupled with a systems understanding, we summarize the challenges and opportunities for promoting the health and wellbeing of the whole nation at national, local, and individual levels. Urbanization and urban expansion result in urban environmental changes, as well as residents' lifestyle change, which can lead independently and synergistically to human health problems. China has undergone an epidemiological transition, shifting from infectious to chronic diseases in a much shorter time frame than many other countries. Environmental risk factors, particularly air and water pollution, are a major contributing source of morbidity and mortality in China. Furthermore, aging population, food support system, and disparity of public service between the migrant worker and local residents are important contributions to China's urban health. At the national level, the central government could improve current environmental policies, food safety laws, and make adjustments to the health care system and to demographic policy. At the local level, local government could incorporate healthy life considerations in urban planning procedures, make improvements to the local food supply, and enforce environmental monitoring and management. At the individual level, urban residents can be exposed to education regarding health behaviour choices while being encouraged to take

Urban CO2 emissions metabolism: The Hestia Project

Science.gov (United States)

Gurney, K. R.; Razlivanov, I.; Zhou, Y.; Song, Y.

2011-12-01

A central expression of urban metabolism is the consumption of energy and the resulting environmental impact, particularly the emission of CO2 and other greenhouse gases. Quantification of energy and emissions has been performed for numerous cities but rarely has this been done in explicit space/time detail. Here, we present the Hestia Project, an effort aimed at building a high resolution (eg. building and road link-specific, hourly) fossil fuel CO2 emissions data product for the urban domain. A complete data product has been built for the city of Indianapolis and work is ongoing for the city of Los Angeles (Figure 1). The effort in Indianapolis is now part of a larger effort aimed at a convergent top-down/bottom-up assessment of greenhouse gas emissions, called INFLUX. Our urban-level quantification relies on a mixture of data and modeling structures. We start with the sector-specific Vulcan Project estimate at the mix of geocoded and county-wide levels. The Hestia aim is to distribute the Vulcan result in space and time. Two components take the majority of effort: buildings and onroad emissions. For the buildings, we utilize an energy building model which we constrain through lidar data, county assessor parcel data and GIS layers. For onroad emissions, we use a combination of traffic data and GIS road layers maintaining vehicle class information. Finally, all pointwise data in the Vulcan Project are transferred to our urban landscape and additional time distribution is performed. A key benefit of the approach taken in this study is the tracking and archiving of fuel and process-level detail (eg. combustion process, other pollutants), allowing for a more thorough understanding and analysis of energy throughputs in the urban environment. Next steps in this research from the metabolism perspective is to consider the carbon footprint of material goods and their lateral transfer in addition to the connection between electricity consumption and production.

[Characteristics of atmospheric NO2 in the Beijing-Tianjin-Hebei region and the Yangtze River Delta analyzed by satellite and ground observations].

Science.gov (United States)

Wang, Ying; Li, Ling-Jun; Liu, Yang

2012-11-01

The interannual variability of NO2 levels in two major Chinese economic regions, the Beijing-Tianjin-Hebei (BTH) economic circle and the Yangtze River Delta (YRD), were studied using multiple years of OMI-retrieved NO2 columns and ground measurements. The NO2 columns were comparable in the two regions, which were - 50% higher than the BTH and YRD regional background and two times higher than the Asia-Europe continental background. Satellite data showed that the high NO2 regions scattered around Beijing and Shanghai in summer, and the coverage of high NO2 regions increased in spring and merged in winter, affecting the entire eastern China. Ground level NO2 concentrations in the urban centers of Beijing and Shanghai were also comparable, which were - 10 times greater than the regional background and 1 000 times higher than the Asia-Europe continental background. As industries gradually migrated out of the urban centers, the NO2 concentrations in Beijing and Shanghai decreased, but the regional background NO2 concentration in BTH and YRD increased. It reflected in part the impact of NO2 emission reductions related to fossil fuel combustion as a result of air quality control measures in BTH and YRD. NO2 levels during the Beijing 2008 Olympic Games and the Shanghai World Expo 2010 decreased temporarily, but bounced back quickly afterwards, indicating that sustainable air quality improvement can only be achieved through long-term regional efforts.

DNA damage in buccal mucosa cells of pre-school children exposed to high levels of urban air pollutants.

Directory of Open Access Journals (Sweden)

Elisabetta Ceretti

Full Text Available Air pollution has been recognized as a human carcinogen. Children living in urban areas are a high-risk group, because genetic damage occurring early in life is considered able to increase the risk of carcinogenesis in adulthood. This study aimed to investigate micronuclei (MN frequency, as a biomarker of DNA damage, in exfoliated buccal cells of pre-school children living in a town with high levels of air pollution. A sample of healthy 3-6-year-old children living in Brescia, Northern Italy, was investigated. A sample of the children's buccal mucosa cells was collected during the winter months in 2012 and 2013. DNA damage was investigated using the MN test. Children's exposure to urban air pollution was evaluated by means of a questionnaire filled in by their parents that included items on various possible sources of indoor and outdoor pollution, and the concentration of fine particulate matter (PM10, PM2.5 and NO2 in the 1-3 weeks preceding biological sample collection. 181 children (mean age ± SD: 4.3 ± 0.9 years were investigated. The mean ± SD MN frequency was 0.29 ± 0.13%. A weak, though statistically significant, association of MN with concentration of air pollutants (PM10, PM2.5 and NO2 was found, whereas no association was apparent between MN frequency and the indoor and outdoor exposure variables investigated via the questionnaire. This study showed a high MN frequency in children living in a town with heavy air pollution in winter, higher than usually found among children living in areas with low or medium-high levels of air pollution.

Illuminance Level in the Urban Fabric and in the Room

DEFF Research Database (Denmark)

Iversen, Anne; Nielsen, Toke Rammer; Svendsen, Svend

2011-01-01

The decisions made on the urban planning level could influence the building design at later stages. Many studies have shown that the utilisation of daylight in buildings would result in significant savings in electricity consumption for lighting, while creating a higher quality indoor environment...... of the exterior illuminance levels on fac¸ades with the interior illuminance levels on the working plane. The paper also explains an easy to use tool (EvUrbanplan) developed by the authors, which was applied to their findings in the early stages of urban planning to ensure daylight optimisation in the buildings....

Safety analysis of urban arterials at the meso level.

Science.gov (United States)

Li, Jia; Wang, Xuesong

2017-11-01

Urban arterials form the main structure of street networks. They typically have multiple lanes, high traffic volume, and high crash frequency. Classical crash prediction models investigate the relationship between arterial characteristics and traffic safety by treating road segments and intersections as isolated units. This micro-level analysis does not work when examining urban arterial crashes because signal spacing is typically short for urban arterials, and there are interactions between intersections and road segments that classical models do not accommodate. Signal spacing also has safety effects on both intersections and road segments that classical models cannot fully account for because they allocate crashes separately to intersections and road segments. In addition, classical models do not consider the impact on arterial safety of the immediately surrounding street network pattern. This study proposes a new modeling methodology that will offer an integrated treatment of intersections and road segments by combining signalized intersections and their adjacent road segments into a single unit based on road geometric design characteristics and operational conditions. These are called meso-level units because they offer an analytical approach between micro and macro. The safety effects of signal spacing and street network pattern were estimated for this study based on 118 meso-level units obtained from 21 urban arterials in Shanghai, and were examined using CAR (conditional auto regressive) models that corrected for spatial correlation among the units within individual arterials. Results showed shorter arterial signal spacing was associated with higher total and PDO (property damage only) crashes, while arterials with a greater number of parallel roads were associated with lower total, PDO, and injury crashes. The findings from this study can be used in the traffic safety planning, design, and management of urban arterials. Copyright © 2017 Elsevier Ltd. All

Folded tubular photometer for atmospheric measurements of NO2 and NO

Science.gov (United States)

Birks, John W.; Andersen, Peter C.; Williford, Craig J.; Turnipseed, Andrew A.; Strunk, Stanley E.; Ennis, Christine A.; Mattson, Erick

2018-05-01

We describe and characterize a modular folded tubular photometer for making direct measurements of the concentrations of nitrogen dioxide (NO2) and specify how this method could be extended to measure other pollutants such as sulfur dioxide (SO2), ozone (O3), and black carbon particulate matter. Direct absorbance measurements using this photometer can be made across the spectral range from the ultraviolet (UV) to the near infrared. The absorbance cell makes use of modular components (tubular detection cells and mirror cubes) that allow construction of path lengths of up to 2 m or more while maintaining low cell volumes. The long path lengths and low cell volumes enable sensitive detection of ambient air pollutants down to low part-per-billion levels for gas species and aerosol extinctions down to 1 Mm-1, corresponding to ˜ 0.1 µg m-3 for black carbon particulates. Pressure equalization throughout the stages of the absorbance measurement is shown to be critical to accurate measurements of analyte concentrations. The present paper describes the application of this photometer to direct measurements of nitrogen dioxide (NO2) and the incorporation of design features that also enable measurement of nitric oxide (NO) in the same instrument. Excellent agreement for ambient measurements along an urban roadside was found for both NO2 and NO measured by the folded tubular photometer compared to existing standard techniques. Compared to commonly used methods for measurements of NOx species, the advantages of this approach include (1) an absolute quantification for NO2 based on the Beer-Lambert law, thereby greatly reducing the frequency at which calibrations are required; (2) the direct measurement of NO2 concentration without prior conversion to NO as is required for the commonly used chemiluminescence method; (3) the use of modular components that allow construction of absorbance detection cells of varying lengths for extending the dynamic range of concentrations that can

Field calibration of electrochemical NO2 sensors in a citizen science context

Science.gov (United States)

Mijling, Bas; Jiang, Qijun; de Jonge, Dave; Bocconi, Stefano

2018-03-01

In many urban areas the population is exposed to elevated levels of air pollution. However, real-time air quality is usually only measured at few locations. These measurements provide a general picture of the state of the air, but they are unable to monitor local differences. New low-cost sensor technology is available for several years now, and has the potential to extend official monitoring networks significantly even though the current generation of sensors suffer from various technical issues.Citizen science experiments based on these sensors must be designed carefully to avoid generation of data which is of poor or even useless quality. This study explores the added value of the 2016 Urban AirQ campaign, which focused on measuring nitrogen dioxide (NO2) in Amsterdam, the Netherlands. Sixteen low-cost air quality sensor devices were built and distributed among volunteers living close to roads with high traffic volume for a 2-month measurement period. Each electrochemical sensor was calibrated in-field next to an air monitoring station during an 8-day period, resulting in R2 ranging from 0.3 to 0.7. When temperature and relative humidity are included in a multilinear regression approach, the NO2 accuracy is improved significantly, with R2 ranging from 0.6 to 0.9. Recalibration after the campaign is crucial, as all sensors show a significant signal drift in the 2-month measurement period. The measurement series between the calibration periods can be corrected for after the measurement period by taking a weighted average of the calibration coefficients.Validation against an independent air monitoring station shows good agreement. Using our approach, the standard deviation of a typical sensor device for NO2 measurements was found to be 7 µg m-3, provided that temperatures are below 30 °C. Stronger ozone titration on street sides causes an underestimation of NO2 concentrations, which 75 % of the time is less than 2.3 µg m-3.Our findings show that citizen science

Low Elevation Coastal Zone (LECZ) Urban-Rural Population and Land Area Estimates, Version 2

Data.gov (United States)

National Aeronautics and Space Administration — The Low Elevation Coastal Zone (LECZ) Urban-Rural Population and Land Area Estimates, Version 2 data set consists of country-level estimates of urban population,...

Global Trends of Tropospheric NO2 Observed From Space

Science.gov (United States)

Schneider, P.; van der A, R. J.

2012-04-01

Nitrogen Dioxide (NO2) is one of the major atmospheric pollutants and is primarily emitted by industrial activity and transport. While observations of NO2 are frequently being carried out at air quality stations, such measurements are not able to provide a global perspective of spatial patterns in NO2 concentrations and their associated trends due to the stations' limited spatial representativity and an extremely sparse and often completely non-existent station coverage in developing countries. Satellite observations of tropospheric NO2 are able to overcome this issue and provide an unprecedented global view of spatial patterns in NO2 levels and due to their homogeneity are well suited for studying trends. Here we present results of a global trend analysis from nearly a decade of NO2 observations made by the SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CartograpHY) instrument onboard the Envisat satellite platform. Using only SCIAMACHY data allows for mapping global and regional trends at an unprecedented spatial resolution since no aggregation to the coarser resolution of other sensors is necessary. Monthly average tropospheric NO2 column data was acquired for the period between August 2002 and August 2011. A trend analysis was subsequently performed by fitting a statistical model including a seasonal cycle and linear trend to the time series extracted at each grid cell. The linear trend component and the trend uncertainty were then mapped spatially at both regional and global scales. The results show that spatially contiguous areas of significantly increasing NO2 levels are found primarily in Eastern China, with absolute trends of up to 4.05 (± 0.41) - 1015 molecules cm-2 yr-1 at the gridcell level and large areas showing rapid relative increases of 10-20 percent per year. In addition, many urban agglomerations in Asia and the Middle East similarly exhibit significantly increasing trends, with Dhaka in Bangladesh being the megacity with

Gaseous pollutants on rural and urban nursery schools in Northern Portugal

International Nuclear Information System (INIS)

Nunes, R.A.O.; Branco, P.T.B.S.; Alvim-Ferraz, M.C.M.; Martins, F.G.; Sousa, S.I.V.

2016-01-01

Indoor air quality in nursery schools is different from other schools and this has been largely ignored, particularly in rural areas. Urban and rural nursery schools have different environmental characteristics whose knowledge needs improvement. Thus, this study aimed to evaluate continuously the concentrations of CO_2, CO, NO_2, O_3, CH_2O and total VOC in three rural nursery schools and one urban, being the only one comparing urban and rural nurseries with continuous measurements, thus considering occupation and non-occupation periods. Regarding CO_2, urban nursery recorded higher concentrations (739–2328 mg m"−"3) than rural nurseries (653–1078 mg m"−"3). The influence of outdoor air was the main source of CO, NO_2 and O_3 indoor concentrations. CO and NO_2 concentrations were higher in the urban nursery and O_3 concentrations were higher in rural ones. CH_2O and TVOC concentrations seemed to be related to internal sources, such as furniture and flooring finishing and cleaning products. - Highlights: • This is the only study comparing gaseous pollutants continuously measured in urban and rural nurseries. • Children's risk of exposure occurs mainly in the urban nursery school. • Outdoor air was the main determinant of CO, NO_2 and O_3 indoor concentrations. • There is a need to implement measures to reduce critical situations regarding IAQ. - Gaseous pollutant levels were higher in the urban nursery than in rural ones, except for O_3. High concentrations were due to lack of ventilation, outdoor air and internal sources.

The Measurement of Urbanization Level Based on Entity Space: A Case Study of JingJinJi Region, China

Directory of Open Access Journals (Sweden)

Wen Fenghua

2017-01-01

Full Text Available On the basis of analyzing the pros and cons of different urbanization level measurement methods, this paper puts forward urbanization level measurement method based on entity space and then uses entity space data to describe the urbanization rate of various districts and counties of JingJinJi Region in 2005 and 2009. According to the analysis of time and space differences on such basis, JingJinJi may be divided from high to low order according to the urbanization rate of the entity space: central urban area, urban development area and suburb, which respectively bear different functions. According to the comparison of entity space urbanization rate and population urbanization rate in the aspects of sequence, primacy ratio, zipf index, etc., we find the non-intensive land use status quo of urban development area of JingJinJi and the feature that the distribution of entity space urbanization scale is much uniform than distribution of population urbanization scale. Accordingly, the paper puts forward the following suggestions : (1 The space construction should depend upon function division; (2 The urban development area should pay attention to the construction of the supporting facilities and meanwhile enhance land use rate; (3 The urban construction should be enhanced in small and middle regions and counties surrounding Beijing and Tianjin.

Temporal characterization and regional contribution to O{sub 3} and NO{sub x} at an urban and a suburban site in Nanjing, China

Energy Technology Data Exchange (ETDEWEB)

Xie, Min, E-mail: minxie@nju.edu.cn; Zhu, Kuanguang; Wang, Tijian, E-mail: tjwang@nju.edu.cn; Chen, Pulong; Han, Yong; Li, Shu; Zhuang, Bingliang; Shu, Lei

2016-05-01

To improve our understanding of the interplay among local and regional photochemical pollutants in the typical city of the Yangtze River Delta (YRD) region, the concurrent observation of O{sub 3} and NO{sub x} concentrations at an urban and a suburban site in Nanjing during 2008 is presented. In general, the annual mean O{sub 3} concentration is 2.35 ppbv lower in the downtown than at suburban due to higher NO{sub x} pollution levels correlated with heavy traffic. At both sites, O{sub 3} shows a distinct seasonality with the spring maximum and the winter minimum, while the minimum concentration of NO{sub x} appears in summertime. Besides the chemical processes of O{sub 3} sensitivity in the daytime and the NO{sub x} titration at night, meteorological conditions also play an essential role in these monthly and diurnal variations. The ozone weekend effect that can be attributed to the weekly routine of human activities is observed in the urban atmosphere of Nanjing as well, with O{sub 3} concentrations 2.09 ppbv higher and NO{sub x} concentrations 6.20 ppbv lower on weekends than on weekdays. The chemical coupling of NO, NO{sub 2} and O{sub 3} is investigated to show that the OX-component (O{sub 3} and NO{sub 2}) partitioning point occurs at about 35 ppbv for NO{sub x}, with O{sub 3} being the dominant form at lower levels and NO{sub 2} dominating at higher levels. And it is also discovered that the level of OX is made up of two contributions, including the regional contribution affected by regional background O{sub 3} level and the local contribution correlated with the level of primary pollution. The diurnal peak of regional contribution appears 2–5 h after the peak of local contribution, implying that OX in Nanjing might prominently affected by the pollutants from a short distance. The highest regional contribution and the second highest local contribution lead to the spring peak of O{sub 3} observed in Nanjing, whereas the highest local contribution and the

Radon and NO2 levels and related environmental factors in 100 underground subway platforms over two-year period.

Science.gov (United States)

Hwang, Sung Ho; Park, Jae Bum; Park, Wha Me

2018-01-01

In this study, the environmental factors that affect radon (Rn) and nitrogen dioxide (NO 2 ) levels in subway-station underground platforms are evaluated, and the outdoor NO 2 levels are compared with those obtained for the underground platforms. The Rn and NO 2 levels from May 2013 to September 2015 are determined for lines 1-4 of the Seoul Metro, via calculation of the arithmetic means of the Rn and NO 2 levels with their standard deviations (SDs). The underground Rn levels in 2013 are found to be significantly higher than those recorded in 2015 for the Seoul Metro. In addition, the Rn levels are related to the station depth and construction year. Further, the underground NO 2 levels are shown to be significantly higher than the outdoor levels for all four Seoul Metro subway lines. The Rn levels are also found to vary significantly between months, and are shown to increase gradually with depth from 8 to 20 m. The Rn levels are also higher for stations constructed in the 1980s. Therefore, stricter monitoring of Rn level may be required for stations constructed in the 1980s and/or having platform depths within the 8-20 m range. Island-type platform stations based on granite areas may also require careful attention. Copyright © 2017 Elsevier Ltd. All rights reserved.

Urbanization Level and Vulnerability to Heat-Related Mortality in Jiangsu Province, China.

Science.gov (United States)

Chen, Kai; Zhou, Lian; Chen, Xiaodong; Ma, Zongwei; Liu, Yang; Huang, Lei; Bi, Jun; Kinney, Patrick L

2016-12-01

Although adverse effects of high temperature on mortality have been studied extensively in urban areas, little is known of the heat-mortality associations outside of cities. We investigated whether heat-mortality associations differed between urban and nonurban areas and how urbanicity affected the vulnerability to heat-related mortality. We first analyzed heat-related mortality risk in each of 102 counties in Jiangsu Province, China, during 2009-2013 using a distributed-lag nonlinear model. The county-specific estimates were then pooled for more urban (percentage of urban population ≥ 57.11%) and less urban (percentage of urban population risk comparing the 99th vs. 75th percentiles of temperature was 1.43 [95% posterior intervals (PI): 1.36, 1.50] in less urban counties and 1.26 (95% PI: 1.23, 1.30) in more urban counties. The heat effects on cardiorespiratory mortality followed a similar pattern. Higher education level and prevalence of air conditioning were significantly associated with counties having lower risks, whereas percentage of elderly people was significantly associated with increased risks. Our findings reveal that nonurban areas have significant heat-related mortality risks in Jiangsu, China. These results suggest the need for enhanced adaptation planning in Chinese nonurban areas under a changing climate. Citation: Chen K, Zhou L, Chen X, Ma Z, Liu Y, Huang L, Bi J, Kinney PL. 2016. Urbanization level and vulnerability to heat-related mortality in Jiangsu Province, China. Environ Health Perspect 124:1863-1869; http://dx.doi.org/10.1289/EHP204.

Report card on low level ozone in urban areas

Energy Technology Data Exchange (ETDEWEB)

Onischak, M.

1994-12-31

It has been four years since the Clean Air Act was amended in November of 1990. Much work has been done in this time, and the country is beginning to see real air quality benefits. Although these changes have not completely licked the urban ozone problem yet, they have made a lot of progress. All of the urban areas which have been required to reduce their ozone levels have done a good job of lowering their emissions. While the urban areas have not all been able to meet every federal deadline, the areas have all been able to achieve the control milestones before the mandatory Clean Air Act sanctions have taken effect. Some areas are even ready to declare their ozone problems solved.

Report card on low level ozone in urban areas

International Nuclear Information System (INIS)

Onischak, M.

1994-01-01

It has been four years since the Clean Air Act was amended in November of 1990. Much work has been done in this time, and the country is beginning to see real air quality benefits. Although these changes have not completely licked the urban ozone problem yet, they have made a lot of progress. All of the urban areas which have been required to reduce their ozone levels have done a good job of lowering their emissions. While the urban areas have not all been able to meet every federal deadline, the areas have all been able to achieve the control milestones before the mandatory Clean Air Act sanctions have taken effect. Some areas are even ready to declare their ozone problems solved

Folded tubular photometer for atmospheric measurements of NO2 and NO

Directory of Open Access Journals (Sweden)

J. W. Birks

2018-05-01

Full Text Available We describe and characterize a modular folded tubular photometer for making direct measurements of the concentrations of nitrogen dioxide (NO2 and specify how this method could be extended to measure other pollutants such as sulfur dioxide (SO2, ozone (O3, and black carbon particulate matter. Direct absorbance measurements using this photometer can be made across the spectral range from the ultraviolet (UV to the near infrared. The absorbance cell makes use of modular components (tubular detection cells and mirror cubes that allow construction of path lengths of up to 2 m or more while maintaining low cell volumes. The long path lengths and low cell volumes enable sensitive detection of ambient air pollutants down to low part-per-billion levels for gas species and aerosol extinctions down to 1 Mm−1, corresponding to  ∼  0.1 µg m−3 for black carbon particulates. Pressure equalization throughout the stages of the absorbance measurement is shown to be critical to accurate measurements of analyte concentrations. The present paper describes the application of this photometer to direct measurements of nitrogen dioxide (NO2 and the incorporation of design features that also enable measurement of nitric oxide (NO in the same instrument. Excellent agreement for ambient measurements along an urban roadside was found for both NO2 and NO measured by the folded tubular photometer compared to existing standard techniques. Compared to commonly used methods for measurements of NOx species, the advantages of this approach include (1 an absolute quantification for NO2 based on the Beer–Lambert law, thereby greatly reducing the frequency at which calibrations are required; (2 the direct measurement of NO2 concentration without prior conversion to NO as is required for the commonly used chemiluminescence method; (3 the use of modular components that allow construction of absorbance detection cells of varying lengths for extending the

Urban wet deposition nitrate: a comparison to non-urban deposition

International Nuclear Information System (INIS)

Schultz, J.A.M.

1994-01-01

The concentration of nitrate in both wet and dry deposition has both increased historically and currently, and recently parallels emissions in NO x . Since NO x is produced in amounts comparable to SO 2 , it is an important contributor to acid deposition, and is produced in higher amounts in urban areas due to concentrated sources. Prior to to this study, national acid deposition monitoring networks in the United States have been and remain established in non-urban areas. This research study consisted of a comparison of precipitation sampling and analysis of wet deposition nitrate and pH for each deposition event in each of two urban sites over a 15 mo period. Also, a comparison of urban data and data generated at a nearby non-urban NADP site was made by examination of both monthly and seasonal data. This research suggests that national monitoring programs should consider inclusion of urban and non-urban monitoring sites in order to achieve a more representative regional assessment. 24 refs., 2 figs., 2 tabs

Urbanization and the wealth of nations.

Science.gov (United States)

Bloom, David E; Canning, David; Fink, Günther

2008-02-08

The proportion of a country's population living in urban areas is highly correlated with its level of income. Urban areas offer economies of scale and richer market structures, and there is strong evidence that workers in urban areas are individually more productive, and earn more, than rural workers. However, rapid urbanization is also associated with crowding, environmental degradation, and other impediments to productivity. Overall, we find no evidence that the level of urbanization affects the rate of economic growth. Our findings weaken the rationale for either encouraging or discouraging urbanization as part of a strategy for economic growth.

Empirical analysis on impact of FDI on the level of urbanization in costal areas

Directory of Open Access Journals (Sweden)

Cao Can-Ming

2015-04-01

Full Text Available Purpose: There is a close relationship between FDI and the level of urbanization. the objective of this research is to analyze the relationship between FDI and the level of urbanization in Jiangsu and Guangdong provinces in costal areas.Design/methodology/approach: The author uses the modern econometric methods by panel unit root test, cointegration test, random effects models and fixed effects models, and the data of FDI (2000-2012, urbanization rate, industrial structure and regional GDP of Nanjing, Xuzhou, Suzhou, Wuxi and other 13 cities in Jiangsu Province, Guangzhou, Shenzhen and other 19 cities in Guangdong province, researches the relationship between FDI and urbanization rate.Findings: Models show, FDI was closely correlated with urbanization rate in Jiangsu province and Guangdong province, the highly correlated with industrial structure, while it negatively correlated with the growth of GDP, and the degree of correlation is not high in Jiangsu province, but the high negative correlation in Guangdong province. The results shows the industrial structure and the urbanization rate mainly cause FDI growth.Research limitations/implications: There are many provinces in costal areas of China, this paper just research the relationship between FDI and the level of urbanization in Jiangsu province and Guangdong province, there are some limitations in the study areas and results.Originality/value: The study was the first to successfully apply on random effects model and fixed effects model to study the relationship between FDI and the level of urbanization in coastal areas by competitive analysis. Guangdong and Jiangsu province are the most developed regions, they are the most representative provinces in costal areas of China. Taking these two province as an example, we can analyze the relationship between FDI and the level of urbanization in central and western regions.

Driver exposure to volatile organic compounds, CO, ozone, and NO2 under different driving conditions

International Nuclear Information System (INIS)

Changchuan Chan; Oezkaynak, H.; Spengler, J.D.; Sheldon, L.

1991-01-01

The in-vehicle concentrations of 24 gasoline-related volatile organic compounds (VOCs) and three criteria air pollutants, ozone, carbon monoxide, and nitrogen dioxide, were measured in the summer of 1988, in Raleigh, NC. Two four-door sedan of different ages were used to evaluate in-vehicle concentrations of these compounds under different driving conditions. Factors that could influence driver exposure, such as different traffic patterns, car model, vehicle ventilation conditions, and driving periods, were evaluated. Isopentane was the most abundant aliphatic hydrocarbon and toluene was the most abundant aromatic VOC measured inside the vehicles. In-vehicle VOC and CO concentrations were highest for the urban roadway, second highest for the interstate highway, and lowest for the rural road. The median concentration ratio of urban/interstate/rural for each VOC was about 10/6/1. No differences in in-vehicle VOC concentrations were found between morning and afternoon rush hour driving, but higher in-vehicle ozone and NO 2 concentrations were found during afternoon driving. In-vehicle VOC levels were lowest with the air conditioner on and highest when the vent was open with the fan on. The in-vehicle/car exterior concentration ratio for VOCs, CO, and NO 2 was slightly higher than 1. The VOC concentration measured by a pedestrian on the urban sidewalk was lower than the in-vehicle measurements but higher than the fixed-site measurements but higher than the fixed-site measurements on urban roadways 50 m from streets. The VOC measurements were positively correlated with the CO measurement and negatively correlated with the ozone measurement

Intraspecific variation shapes community-level behavioral responses to urbanization in spiders.

Science.gov (United States)

Dahirel, Maxime; Dierick, Jasper; De Cock, Maarten; Bonte, Dries

2017-09-01

Urban areas are an extreme example of human-changed environments, exposing organisms to multiple and strong selection pressures. Adaptive behavioral responses are thought to play a major role in animals' success or failure in such new environments. Approaches based on functional traits have proven especially valuable to understand how species communities respond to environmental gradients. Until recently, they have, however, often ignored the potential consequences of intraspecific trait variation (ITV). When ITV is prevalent, it may highly impact ecological processes and resilience against stressors. This may be especially relevant in animals, in which behavioral traits can be altered very flexibly at the individual level to track environmental changes. We investigated how species turnover and ITV influenced community-level behavioral responses in a set of 62 sites of varying levels of urbanization, using orb web spiders and their webs as models of foraging behavior. ITV alone explained around one-third of the total trait variation observed among communities. Spider web structure changed according to urbanization, in ways that increase the capture efficiency of webs in a context of smaller urban prey. These trait shifts were partly mediated by species turnover, but ITV increased their magnitude, potentially helping to buffer the effects of environmental changes on communities. The importance of ITV varied depending on traits and on the spatial scale at which urbanization was considered. Despite being neglected from community-level analyses in animals, our results highlight the importance of accounting for intraspecific trait variation to fully understand trait responses to (human-induced) environmental changes and their impact on ecosystem functioning. © 2017 by the Ecological Society of America.

County-level heat vulnerability of urban and rural residents in Tibet, China.

Science.gov (United States)

Bai, Li; Woodward, Alistair; Cirendunzhu; Liu, Qiyong

2016-01-12

Tibet is especially vulnerable to climate change due to the relatively rapid rise of temperature over past decades. The effects on mortality and morbidity of extreme heat in Tibet have been examined in previous studies; no heat adaptation initiatives have yet been implemented. We estimated heat vulnerability of urban and rural populations in 73 Tibetan counties and identified potential areas for public health intervention and further research. According to data availability and vulnerability factors identified previously in Tibet and elsewhere, we selected 10 variables related to advanced age, low income, illiteracy, physical and mental disability, small living spaces and living alone. We separately created and mapped county-level cumulative heat vulnerability indices for urban and rural residents by summing up factor scores produced by a principal components analysis (PCA). For both study populations, PCA yielded four factors with similar structure. The components for rural and urban residents explained 76.5 % and 77.7 % respectively of the variability in the original vulnerability variables. We found spatial variability of heat vulnerability across counties, with generally higher vulnerability in high-altitude counties. Although we observed similar median values and ranges of the cumulative heat vulnerability index values among urban and rural residents overall, the pattern varied strongly from one county to another. We have developed a measure of population vulnerability to high temperatures in Tibet. These are preliminary findings, but they may assist targeted adaptation plans in response to future rapid warming in Tibet.

An impact assessment of sustainable technologies for the Chinese urban residential sector at provincial level

Science.gov (United States)

Xing, Rui; Hanaoka, Tatsuya; Kanamori, Yuko; Dai, Hancheng; Masui, Toshihiko

2015-06-01

Recently, energy use in the urban residential sector of China has drastically increased due to higher incomes and urbanization. The fossil fuels dominant energy supply has since worsened the air quality, especially in urban areas. In this study we estimate the future energy service demands in Chinese urban residential areas, and then use an AIM/Enduse model to evaluate the emission reduction potential of CO2, SO2, NOx and PM. Considering the climate diversity and its impact on household energy service demands, our analysis is down-scaled to the provincial-level. The results show that in most of the regions, penetration of efficient technologies will bring CO2 emission reductions of over 20% compared to the baseline by the year 2030. Deployment of energy efficient technologies also co-benefits GHG emission reduction. However, efficient technology selection appears to differ across provinces due to climatic variation and economic disparity. For instance, geothermal heating technology is effective for the cold Northern areas while biomass technology contributes to emission reduction the most in the warm Southern areas.

Suicide risk in relation to level of urbanicity - a population-based linkage study

DEFF Research Database (Denmark)

Qin, Ping

2005-01-01

BACKGROUND: The extent to which the high suicide rate in urban areas is influenced by exposures to risk factors for suicide other than urbanicity remains unknown. This population-based study aims to investigate suicide risk in relation to the level of urbanicity in the context of other factors...

Phytoestrogens levels determination in the cord blood from Malaysia rural and urban populations

International Nuclear Information System (INIS)

Mustafa, A.M.; Malintan, N.T.; Seelan, S.; Zhan, Z.; Mohamed, Z.; Hassan, J.; Pendek, R.; Hussain, R.; Ito, N.

2007-01-01

This study is a result of an analysis of free and conjugated phytoestrogens daidzein, genistein, daidzin, genistin and coumesterol in human cord blood plasma using LCMS. Cord blood was collected from urban and rural populations of Malaysia (n = 300) to establish a simple preliminary database on the levels of the analyzed compounds in the collected samples. The study also aimed to look at the levels of phytoestrogens in babies during birth as this may have a profound effect on the developmental process. The sample clean up was carried out by solid-phase extraction using C18 column and passed through DEAE sephadex gel before analysis by LCMS. The mean concentrations of total phytoestrogens were daidzein (1.4 ± 2.9 ng/ml), genistein (3.7 ± 2.8 ng/ml), daidzin (3.5 ± 3.1 ng/ml), genistin (19.5 ± 4.2 ng/ml) and coumesterol (3.3 ± 3.3 ng/ml). Distribution of phytoestrogen was found to be higher in samples collected from rural areas compared to that of urban areas

Panel estimation for urbanization, energy consumption and CO2 emissions: A regional analysis in China

International Nuclear Information System (INIS)

Zhang Chuanguo; Lin Yan

2012-01-01

As urbanization accelerates, urban areas play a leading role in energy consumption and CO 2 emissions in China. The existing research is extensively concerned with the relationships between urbanization, energy consumption and CO 2 emissions in recent years, but little attention has been paid to the regional differences. This paper is an analysis of the impact of urbanization on energy consumption and CO 2 emissions at the national and regional levels using the STIRPAT model and provincial panel data from 1995 to 2010 in China. The results showed that urbanization increases energy consumption and CO 2 emissions in China. The effects of urbanization on energy consumption vary across regions and decline continuously from the western region to the central and eastern regions. The impact of urbanization on CO 2 emissions in the central region is greater than that in the eastern region. The impact of urbanization on energy consumption is greater than the impact on CO 2 emissions in the eastern region. And some evidences support the argument of compact city theory. These results not only contribute to advancing the existing literature, but also merit particular attention from policy makers and urban planners in China. - Highlights: ► We analyze the impact of urbanization on energy use and CO 2 emissions in China. ► Urbanization increases energy consumption and CO 2 emissions in China. ► The effects of urbanization on energy use and CO 2 emissions vary across regions.

Improving urban ecosystems resilience at a city level

Science.gov (United States)

Ferreira, António J. D.; Ferrreira, Carla S. S.; Malta, Miguel; Soares, Daniel D. J.; Pardal, João; Vilhena, José

2013-04-01

The sustainability of urban communities is at risk in a global change context, where environmental problems and the constraints posed by a limited access to key raw materials, energy and sanitation will cause profound changes on the way we interact with the natural environment. Major changes are expected on processes magnitude and connectivity at various scales, with profound impacts on the environmental and well-being problems posed by the packing of high density of people in restricted areas, that have to be dealt with. The conventional approach is to find technological solutions that are often expensive and inefficient, especially in what concerns the use of energy and raw materials, limiting long term sustainability and urban ecosystems' resilience, and consequent impacts on the quality of life and health of urban populations. To improve city resilience in face of global change threats (climatic change, growing world population, land use change, lower energy availability, reduced mobility as a result of fossil fuels stringency and costs), we need to develop a nested approach binding together various greening actions and management of green infrastructures at various scales (i.e. household, neighbourhood, city and urban/wildland interface). This paper presents the conceptual strategy being developed at the Coimbra City (Centre of Portugal) to increase the resilience of urban ecosystems, using them to reduce natural risk occurrence (such as flash floods), the promotion of human health and increasing city resilience towards an improve food self sufficiency. We present a discussion and evaluation of the different solutions designed and implemented to improve the overall urban sustainability at different scales of intervention, from the household solutions to more structural solutions such as the recover of riparian forests or the preservation and improvement of green corridors. Of paramount importance to improve urban ecosystem resilience is the development of new

PM10 concentration levels at an urban and background site in Cyprus: the impact of urban sources and dust storms.

Science.gov (United States)

Achilleos, Souzana; Evans, John S; Yiallouros, Panayiotis K; Kleanthous, Savvas; Schwartz, Joel; Koutrakis, Petros

2014-12-01

Air quality in Cyprus is influenced by both local and transported pollution, including desert dust storms. We examined PM10 concentration data collected in Nicosia (urban representative) from April 1, 1993, through December 11, 2008, and in Ayia Marina (rural background representative) from January 1, 1999, through December 31, 2008. Measurements were conducted using a Tapered Element Oscillating Micro-balance (TEOM). PM10 concentrations, meteorological records, and satellite data were used to identify dust storm days. We investigated long-term trends using a Generalized Additive Model (GAM) after controlling for day of week, month, temperature, wind speed, and relative humidity. In Nicosia, annual PM10 concentrations ranged from 50.4 to 63.8 μg/m3 and exceeded the EU annual standard limit enacted in 2005 of 40 μg/m3 every year A large, statistically significant impact of urban sources (defined as the difference between urban and background levels) was seen in Nicosia over the period 2000-2008, and was highest during traffic hours, weekdays, cold months, and low wind conditions. Our estimate of the mean (standard error) contribution of urban sources to the daily ambient PM10 was 24.0 (0.4) μg/m3. The study of yearly trends showed that PM10 levels in Nicosia decreased from 59.4 μg/m3 in 1993 to 49.0 μg/m3 in 2008, probably in part as a result of traffic emission control policies in Cyprus. In Ayia Marina, annual concentrations ranged from 27.3 to 35.6 μg/m3, and no obvious time trends were observed. The levels measured at the Cyprus background site are comparable to background concentrations reported in other Eastern Mediterranean countries. Average daily PM10 concentrations during desert dust storms were around 100 μg/m3 since 2000 and much higher in earlier years. Despite the large impact ofdust storms and their increasing frequency over time, dust storms were responsible for a small fraction of the exceedances of the daily PM10 limit. Implications: This

Urbanization and the more-individuals hypothesis.

Science.gov (United States)

Chiari, Claudia; Dinetti, Marco; Licciardello, Cinzia; Licitra, Gaetano; Pautasso, Marco

2010-03-01

1. Urbanization is a landscape process affecting biodiversity world-wide. Despite many urban-rural studies of bird assemblages, it is still unclear whether more species-rich communities have more individuals, regardless of the level of urbanization. The more-individuals hypothesis assumes that species-rich communities have larger populations, thus reducing the chance of local extinctions. 2. Using newly collated avian distribution data for 1 km(2) grid cells across Florence, Italy, we show a significantly positive relationship between species richness and assemblage abundance for the whole urban area. This richness-abundance relationship persists for the 1 km(2) grid cells with less than 50% of urbanized territory, as well as for the remaining grid cells, with no significant difference in the slope of the relationship. These results support the more-individuals hypothesis as an explanation of patterns in species richness, also in human modified and fragmented habitats. 3. However, the intercept of the species richness-abundance relationship is significantly lower for highly urbanized grid cells. Our study confirms that urban communities have lower species richness but counters the common notion that assemblages in densely urbanized ecosystems have more individuals. In Florence, highly inhabited areas show fewer species and lower assemblage abundance. 4. Urbanized ecosystems are an ongoing large-scale natural experiment which can be used to test ecological theories empirically.

NO2 fluxes from Tijuana using a mobile mini-DOAS during Cal-Mex 2010

Science.gov (United States)

Rivera, Claudia; Barrera, Hugo; Grutter, Michel; Zavala, Miguel; Galle, Bo; Bei, Naifang; Li, Guohui; Molina, Luisa T.

2013-05-01

NO2 fluxes were measured using a mobile mini-DOAS during Cal-Mex 2010 field study, between May 15 and June 30, 2010, from the urban area of Tijuana, Baja California as well as the Rosarito power plant. The average calculated NO2 fluxes were 328 ± 184 (269 ± 201) g s-1, and 23.4 ± 4.9 (12.9 ± 11.9) g s-1 for Tijuana urban area and Rosarito power plant, respectively, using model based wind fields and onsite measurements (in parenthesis). Wind speed and wind direction data needed to estimate the fluxes were both modeled and obtained from radiosondes launched regularly during the field campaign, whereas the mixing layer height throughout the entire field campaign was measured using a ceilometer. Large variations in the NO2 fluxes from both the Tijuana urban area and Rosarito power plant were observed during Cal-Mex 2010; however, the variability was less when model based wind fields were used. Qualitative comparisons of modeled and measured plumes from the Tijuana urban area and Rosarito power plant showed good agreement.

Modern urban design and townscape; Kindai no toshi sekkei to `keikan no hakken`

Energy Technology Data Exchange (ETDEWEB)

Higuchi, T [Niigata University, Niigata (Japan). Faculty of Engineering

1995-01-01

Through characteristics and examples of urban model, the present paper explains how the urban plan and design are conceived. It also does the recent trend of scenic arrangement in Japan. The progressionists base the urban model on the rationalism. They condition the urban space to be hygienic, functional, regulatory, geometric and orderly, which means the negation of cultural scenery with stores and houses on streets. Such a model is applied to the urban development in Japan. The culturists aim at an urban model characterized by the small-scale, intensive, organic and asymmetric urban space. Its scenery is cultural, local and organic. Its examples are given by British garden cities. Aiming at an urban model descended from the culturism, the townscape school plans the urban arrangement based on the individual experience and not the enlightening position. They commit a fault by disregarding the problem for the urban entirety and losing its philosophy. In Japan, the scenery is being built up through the preservation of historic townscape, scenic arrangement of stores and houses on streets, and planning of the park. 11 refs., 4 figs.

Mizan Law Review - Vol 5, No 2 (2011)

African Journals Online (AJOL)

Mizan Law Review - Vol 5, No 2 (2011) ... Ethiopian Law of International Carriage by Air: An Overview · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT ... Comment: Overview of the Core Changes in the New Ethiopian Urban Land Leasehold Proclamation · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

A space-based, high-resolution view of notable changes in urban NO _x pollution around the world (2005-2014)

Energy Technology Data Exchange (ETDEWEB)

Duncan, Bryan N. [NASA Goddard Space Flight Center, Greenbelt Maryland USA; Lamsal, Lok N. [NASA Goddard Space Flight Center, Greenbelt Maryland USA; Goddard Earth Sciences Technology and Research, Universities Space Research Association, Columbia Maryland USA; Thompson, Anne M. [NASA Goddard Space Flight Center, Greenbelt Maryland USA; Yoshida, Yasuko [NASA Goddard Space Flight Center, Greenbelt Maryland USA; Science Systems and Applications, Inc., Greenbelt Maryland USA; Lu, Zifeng [Argonne National Laboratory, Argonne Illinois USA; Streets, David G. [Argonne National Laboratory, Argonne Illinois USA; Hurwitz, Margaret M. [NASA Goddard Space Flight Center, Greenbelt Maryland USA; GESTAR, Morgan State University, Baltimore Maryland USA; Pickering, Kenneth E. [NASA Goddard Space Flight Center, Greenbelt Maryland USA

2016-01-20

Nitrogen oxides (NO_x = NO + NO₂) are produced during combustion processes and, thus may serve as a proxy for fossil fuel-based energy usage and coemitted greenhouse gases and other pollutants. We use high-resolution nitrogen dioxide (NO₂) data from the Ozone Monitoring Instrument (OMI) to analyze changes in urban NO₂ levels around the world from 2005 to 2014, finding complex heterogeneity in the changes. We discuss several potential factors that seem to determine these NO_x changes. First, environmental regulations resulted in large decreases. The only large increases in the United States may be associated with three areas of intensive energy activity. Second, elevated NO₂ levels were observed over many Asian, tropical, and subtropical cities that experienced rapid economic growth. Two of the largest increases occurred over recently expanded petrochemical complexes in Jamnagar (India) and Daesan (Korea). Third, pollution transport from China possibly influenced the Republic of Korea and Japan, diminishing the impact of local pollution controls. However, in China, there were large decreases over Beijing, Shanghai, and the Pearl River Delta, which were likely associated with local emission control efforts. Fourth, civil unrest and its effect on energy usage may have resulted in lower NO₂ levels in Libya, Iraq, and Syria. Fifth, spatial heterogeneity within several megacities may reflect mixed efforts to cope with air quality degradation. We also show the potential of high-resolution data for identifying NO_x emission sources in regions with a complex mix of sources. Finally, intensive monitoring of the world's tropical/subtropical megacities will remain a priority, as their populations and emissions of pollutants and greenhouse gases are expected to increase significantly.

Using Satellite Remote Sensing and Modelling for Insights into N02 Air Pollution and NO2 Emissions

Science.gov (United States)

Lamsal, L. N.; Martin, R. V.; Krotkov, N. A.; Bucsela, E. J.; Celarier, E. A.; vanDonkelaar, A.; Parrish, D.

2012-01-01

Nitrogen oxides (NO(x)) are key actors in air quality and climate change. Satellite remote sensing of tropospheric NO2 has developed rapidly with enhanced spatial and temporal resolution since initial observations in 1995. We have developed an improved algorithm and retrieved tropospheric NO2 columns from Ozone Monitoring Instrument. Column observations of tropospheric NO2 from the nadir-viewing satellite sensors contain large contributions from the boundary layer due to strong enhancement of NO2 in the boundary layer. We infer ground-level NO2 concentrations from the OMI satellite instrument which demonstrate significant agreement with in-situ surface measurements. We examine how NO2 columns measured by satellite, ground-level NO2 derived from satellite, and NO(x) emissions obtained from bottom-up inventories relate to world's urban population. We perform inverse modeling analysis of NO2 measurements from OMI to estimate "top-down" surface NO(x) emissions, which are used to evaluate and improve "bottom-up" emission inventories. We use NO2 column observations from OMI and the relationship between NO2 columns and NO(x) emissions from a GEOS-Chem model simulation to estimate the annual change in bottom-up NO(x) emissions. The emission updates offer an improved estimate of NO(x) that are critical to our understanding of air quality, acid deposition, and climate change.

Suicide risk in relation to level of urbanicity - a population-based linkage study

DEFF Research Database (Denmark)

Qin, Ping

2005-01-01

from various Danish longitudinal registers. Data were analysed with conditional logistic regression. RESULTS: This study confirms that people living in more urbanized areas are at a higher risk of suicide than their counterparts in less urbanized areas. However, this excess risk is largely eliminated...... when adjusted for personal marital, income, and ethnic differences; it is even reversed when further adjusted for psychiatric status. Moreover, the impact of urbanicity on suicide risk differs significantly by sex and across age. Urban living reduces suicide risk significantly among men, especially......BACKGROUND: The extent to which the high suicide rate in urban areas is influenced by exposures to risk factors for suicide other than urbanicity remains unknown. This population-based study aims to investigate suicide risk in relation to the level of urbanicity in the context of other factors...

Effect of air pollution on peri-urban agriculture: a case study

International Nuclear Information System (INIS)

Agrawal, M.; Singh, B.; Rajput, M.; Marshall, F.; Bell, J.N.B.

2003-01-01

Peri-urban agriculture is vital for the urban populations of many developing countries. Increases in both industrialization and urbanization, and associated air pollution threaten urban food production and its quality. Six hour mean concentrations were monitored for SO 2 , NO 2 and O 3 and plant responses were measured in terms of physiological characteristics, pigment, biomass and yield. Parameter reductions in mung bean (Vigna radiata), palak (Beta vulgaris), wheat (Triticum aestivum) and mustard (Brassica compestris) grown within the urban fringes of Varanasi, India correlated directly with the gaseous pollutants levels. The magnitude of response involved all three gaseous pollutants at peri-urban sites; O 3 had more influence at a rural site. The study concluded that air pollution in Varanasi could negatively influence crop yield. - Urban air pollution has a negative impact on peri-urban agriculture

Effect of air pollution on peri-urban agriculture: a case study

Energy Technology Data Exchange (ETDEWEB)

Agrawal, M.; Singh, B.; Rajput, M.; Marshall, F.; Bell, J.N.B

2003-12-01

Peri-urban agriculture is vital for the urban populations of many developing countries. Increases in both industrialization and urbanization, and associated air pollution threaten urban food production and its quality. Six hour mean concentrations were monitored for SO{sub 2}, NO{sub 2} and O{sub 3} and plant responses were measured in terms of physiological characteristics, pigment, biomass and yield. Parameter reductions in mung bean (Vigna radiata), palak (Beta vulgaris), wheat (Triticum aestivum) and mustard (Brassica compestris) grown within the urban fringes of Varanasi, India correlated directly with the gaseous pollutants levels. The magnitude of response involved all three gaseous pollutants at peri-urban sites; O{sub 3} had more influence at a rural site. The study concluded that air pollution in Varanasi could negatively influence crop yield. - Urban air pollution has a negative impact on peri-urban agriculture.

Effects of Urban Landscape Pattern on PM2.5 Pollution—A Beijing Case Study

Science.gov (United States)

Wu, Jiansheng; Xie, Wudan; Li, Weifeng; Li, Jiacheng

2015-01-01

PM2.5 refers to particulate matter (PM) in air that is less than 2.5μm in aerodynamic diameter, which has negative effects on air quality and human health. PM2.5 is the main pollutant source in haze occurring in Beijing, and it also has caused many problems in other cities. Previous studies have focused mostly on the relationship between land use and air quality, but less research has specifically explored the effects of urban landscape patterns on PM2.5. This study considered the rapidly growing and heavily polluted Beijing, China. To better understand the impact of urban landscape pattern on PM2.5 pollution, five landscape metrics including PLAND, PD, ED, SHEI, and CONTAG were applied in the study. Further, other data, such as street networks, population density, and elevation considered as factors influencing PM2.5, were obtained through RS and GIS. By means of correlation analysis and stepwise multiple regression, the effects of landscape pattern on PM2.5 concentration was explored. The results showed that (1) at class-level, vegetation and water were significant landscape components in reducing PM2.5 concentration, while cropland played a special role in PM2.5 concentration; (2) landscape configuration (ED and PD) features at class-level had obvious effects on particulate matter; and (3) at the landscape-level, the evenness (SHEI) and fragmentation (CONTAG) of the whole landscape related closely with PM2.5 concentration. Results of this study could expand our understanding of the role of urban landscape pattern on PM2.5 and provide useful information for urban planning. PMID:26565799

Effects of Urban Landscape Pattern on PM2.5 Pollution--A Beijing Case Study.

Science.gov (United States)

Wu, Jiansheng; Xie, Wudan; Li, Weifeng; Li, Jiacheng

2015-01-01

PM2.5 refers to particulate matter (PM) in air that is less than 2.5 μm in aerodynamic diameter, which has negative effects on air quality and human health. PM2.5 is the main pollutant source in haze occurring in Beijing, and it also has caused many problems in other cities. Previous studies have focused mostly on the relationship between land use and air quality, but less research has specifically explored the effects of urban landscape patterns on PM2.5. This study considered the rapidly growing and heavily polluted Beijing, China. To better understand the impact of urban landscape pattern on PM2.5 pollution, five landscape metrics including PLAND, PD, ED, SHEI, and CONTAG were applied in the study. Further, other data, such as street networks, population density, and elevation considered as factors influencing PM2.5, were obtained through RS and GIS. By means of correlation analysis and stepwise multiple regression, the effects of landscape pattern on PM2.5 concentration was explored. The results showed that (1) at class-level, vegetation and water were significant landscape components in reducing PM2.5 concentration, while cropland played a special role in PM2.5 concentration; (2) landscape configuration (ED and PD) features at class-level had obvious effects on particulate matter; and (3) at the landscape-level, the evenness (SHEI) and fragmentation (CONTAG) of the whole landscape related closely with PM2.5 concentration. Results of this study could expand our understanding of the role of urban landscape pattern on PM2.5 and provide useful information for urban planning.

Differences in cardiovascular risk factors in rural, urban and rural-to-urban migrants in Peru

Science.gov (United States)

Miranda, J. Jaime; Gilman, Robert H.; Smeeth, Liam

2011-01-01

Objectives To assess differences in cardiovascular risk profiles among rural-to-urban migrants and non-migrant groups. Design Cross-sectional study. Setting Ayacucho and Lima, Peru Participants rural (n=201); rural-urban migrants (n=589) and urban (n=199). Main outcome measures Cardiovascular risk factors were assessed according to migrant status (migrants vs. non-migrants), age at first migration, length of residency in an urban area and lifetime exposure to an urban area. Results For most risk factors, the migrant group had intermediate levels of risk between those observed for the rural and urban groups. Prevalences, for rural, migrant and urban groups, was 3%, 20% and 33% for obesity and 0.8%, 3% and 6% for type-2 diabetes. This gradient of risk was not observed uniformly across all risk factors. Blood pressure did not show a clear gradient of difference between groups. The migrant group had similar systolic blood pressure (SBP) but lower diastolic blood pressure (DBP) than the rural group. The urban group had higher SBP but similar DBP than rural group. Hypertension was more prevalent among the urban (29%) compared to both rural and migrant groups (11% and 16% respectively). For HbA1c, although the urban group had higher levels, the migrant and rural groups were similar to each other. No differences were observed in triglycerides between the three groups. Within migrants, those who migrated when aged older than 12 years had higher odds of diabetes, impaired fasting glucose and metabolic syndrome compared to people who migrated at younger ages. Adjustment for age, sex and socioeconomic indicators had little impact on the patterns observed. Conclusions The impact of rural to urban migration on cardiovascular risk profile is not uniform across different risk factors, and is further influenced by the age at which migration occurs. A gradient in levels was observed for some risk factors across study groups. This observation indicates that urbanization is indeed

A method for evaluating spatially-resolved NOx emissions using Kalman filter inversion, direct sensitivities, and space-based NO2 observations

Directory of Open Access Journals (Sweden)

R. V. Martin

2008-09-01

Full Text Available An inverse modeling method was developed and tested for identifying possible biases in emission inventories using satellite observations. The relationships between emission inputs and modeled ambient concentrations were estimated using sensitivities calculated with the decoupled direct method in three dimensions (DDM-3D implemented within the framework of the Community Multiscale Air Quality (CMAQ regional model. As a case study to test the approach, the method was applied to regional ground-level NOx emissions in the southeastern United States as constrained by observations of NO2 column densities derived from the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY satellite instrument. A controlled "pseudodata" scenario with a known solution was used to establish that the methodology can achieve the correct solution, and the approach was then applied to a summer 2004 period where the satellite data are available. The results indicate that emissions biases differ in urban and rural areas of the southeast. The method suggested slight downward (less than 10% adjustment to urban emissions, while rural region results were found to be highly sensitive to NOx processes in the upper troposphere. As such, the bias in the rural areas is likely not solely due to biases in the ground-level emissions. It was found that CMAQ was unable to predict the significant level of NO2 in the upper troposphere that was observed during the NASA Intercontinental Chemical Transport Experiment (INTEX measurement campaign. The best correlation between satellite observations and modeled NO2 column densities, as well as comparison to ground-level observations of NO2, was obtained by performing the inverse while accounting for the significant presence of NO2 in the upper troposphere not captured by the regional model.

International Journal of Development and Policy Studies - Vol 2, No ...

African Journals Online (AJOL)

International Journal of Development and Policy Studies - Vol 2, No 1 (2006) .... Locating oppressive use of language: a study of linguistic violence on nigerian ... trafficking - poverty link based on urban development and planning process ...

Increased body size along urbanization gradients at both community and intraspecific level in macro-moths.

Science.gov (United States)

Merckx, Thomas; Kaiser, Aurélien; Van Dyck, Hans

2018-05-23

Urbanization involves a cocktail of human-induced rapid environmental changes and is forecasted to gain further importance. Urban-heat-island effects result in increased metabolic costs expected to drive shifts towards smaller body sizes. However, urban environments are also characterized by strong habitat fragmentation, often selecting for dispersal phenotypes. Here, we investigate to what extent, and at which spatial scale(s), urbanization drives body size shifts in macro-moths-an insect group characterized by positive size-dispersal links-at both the community and intraspecific level. Using light and bait trapping as part of a replicated, spatially nested sampling design, we show that despite the observed urban warming of their woodland habitat, macro-moth communities display considerable increases in community-weighted mean body size because of stronger filtering against small species along urbanization gradients. Urbanization drives intraspecific shifts towards increased body size too, at least for a third of species analysed. These results indicate that urbanization drives shifts towards larger, and hence, more mobile species and individuals in order to mitigate low connectivity of ecological resources in urban settings. Macro-moths are a key group within terrestrial ecosystems, and since body size is central to species interactions, such urbanization-driven phenotypic change may impact urban ecosystem functioning, especially in terms of nocturnal pollination and food web dynamics. Although we show that urbanization's size-biased filtering happens simultaneously and coherently at both the inter- and intraspecific level, we demonstrate that the impact at the community level is most pronounced at the 800 m radius scale, whereas species-specific size increases happen at local and landscape scales (50-3,200 m radius), depending on the species. Hence, measures-such as creating and improving urban green infrastructure-to mitigate the effects of urbanization on

Evaluating strategies to reduce urban air pollution

Science.gov (United States)

Duque, L.; Relvas, H.; Silveira, C.; Ferreira, J.; Monteiro, A.; Gama, C.; Rafael, S.; Freitas, S.; Borrego, C.; Miranda, A. I.

2016-02-01

During the last years, specific air quality problems have been detected in the urban area of Porto (Portugal). Both PM10 and NO2 limit values have been surpassed in several air quality monitoring stations and, following the European legislation requirements, Air Quality Plans were designed and implemented to reduce those levels. In this sense, measures to decrease PM10 and NO2 emissions have been selected, these mainly related to the traffic sector, but also regarding the industrial and residential combustion sectors. The main objective of this study is to investigate the efficiency of these reduction measures with regard to the improvement of PM10 and NO2 concentration levels over the Porto urban region using a numerical modelling tool - The Air Pollution Model (TAPM). TAPM was applied over the study region, for a simulation domain of 80 × 80 km2 with a spatial resolution of 1 × 1 km2. The entire year of 2012 was simulated and set as the base year for the analysis of the impacts of the selected measures. Taking into account the main activity sectors, four main scenarios have been defined and simulated, with focus on: (1) hybrid cars; (2) a Low Emission Zone (LEZ); (3) fireplaces and (4) industry. The modelling results indicate that measures to reduce PM10 should be focused on residential combustion (fireplaces) and industrial activity and for NO2 the strategy should be based on the traffic sector. The implementation of all the defined scenarios will allow a total maximum reduction of 4.5% on the levels of both pollutants.

Motorcycle emissions and fuel consumption in urban and rural driving conditions.

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Chen, K S; Wang, W C; Chen, H M; Lin, C F; Hsu, H C; Kao, J H; Hu, M T

2003-08-01

This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO(x)=NO+NO(2)) and carbon dioxide (CO(2)), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO(x) emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations.

Motorcycle emissions and fuel consumption in urban and rural driving conditions

International Nuclear Information System (INIS)

Chen, K.S.; Wang, W.C.; Chen, H.M.; Lin, C.F.; Hsu, H.C.; Kao, J.H.; Hu, M.T.

2003-01-01

This work reports sampling of motorcycle on-road driving cycles in actual urban and rural environments and the development of representative driving cycles using the principle of least total variance in individual regions. Based on the representative driving cycles in individual regions, emission factors for carbon monoxide (CO), hydrocarbons (HC), nitrogen oxides (NO x =NO+NO 2 ) and carbon dioxide (CO 2 ), as well as fuel consumption, were determined using a chassis dynamometer. The measurement results show that the representative driving cycles are almost identical in the three largest cities in Taiwan, but they differ significantly from the rural driving cycle. Irrespective of driving conditions, emission factors differ insignificantly between the urban and rural regions at a 95% confidence level. However, the fuel consumption in urban centers is approximately 30% higher than in the rural regions, with driving conditions in the former usually poor compared to the latter. Two-stroke motorcycles generally have considerably higher HC emissions and quite lower NO x emissions than those of four-stroke motorcycles. Comparisons with other studies suggest that factors such as road characteristics, traffic volume, vehicle type, driving conditions and driver behavior may affect motorcycle emission levels in real traffic situations

Urban versus rural lifestyle in adolescents: associations between environment, physical activity levels and sedentary behavior.

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Regis, Manuela Ferreira; Oliveira, Luciano Machado Ferreira Tenório de; Santos, Ana Raquel Mendes Dos; Leonidio, Ameliane da Conceição Reubens; Diniz, Paula Rejane Beserra; Freitas, Clara Maria Silvestre Monteiro de

2016-01-01

To analyze the levels of physical activity and sedentary behavior in adolescents living in urban and rural areas. An epidemiological, cross-section study with quantitative design, carried out at the regional level. The sample comprised 6,234 students aged 14 to 19 years, selected using random cluster sampling. The χ2 test and binary logistic regression were used in the analysis. A total of 74.5% of adolescents lived in urban areas. After adjustment, rural residents spent less time watching television (odds ratio - OR: 0.45; 95% confidence interval - 95%CI: 0.39-0.52), using a computer and/or playing video games (OR: 0.30; 95%CI: 0.22-0.42), or sitting down (OR: 0.66; 95%CI: 0.54-0.80); chose passive leisure less often (OR: 0.83; 95%IC: 0.72-0.95) and were less likely to be classified as insufficiently active (OR: 0.88; 95%IC: 0.78-0.99) when compared to urban residents, regardless of sex or age. The fact that adolescents living in rural areas who did not work were more likely to be classified as insufficiently active (OR: 2.59; 95%CI: 2.07-3.24) emphasized the significant role of occupation in physical activity levels in this group. Adolescents living in rural areas were less exposed to the sedentary behaviors, chose more active leisure, and had higher levels of physical activity. Place of residence and occupation may play a major role in youth lifestyle. Analisar os níveis de atividade física e o comportamento sedentário em adolescentes das áreas urbanas e rurais. Estudo epidemiológico, transversal, com abordagem quantitativa e abrangência estadual, cuja amostra foi constituída por 6.234 estudantes (14 a 19 anos), selecionados por meio de uma estratégia de amostragem aleatória de conglomerados. As análises foram realizadas por meio do teste χ2 e da regressão logística binária. Na amostra, 74,5% dos adolescentes eram residentes em área urbana. Após o ajuste, constatou-se que os adolescentes oriundos da área rural usavam menos televisão (odds

Urban bat communities are affected by wetland size, quality, and pollution levels.

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Straka, Tanja Maria; Lentini, Pia Eloise; Lumsden, Linda Faye; Wintle, Brendan Anthony; van der Ree, Rodney

2016-07-01

Wetlands support unique biota and provide important ecosystem services. These services are highly threatened due to the rate of loss and relative rarity of wetlands in most landscapes, an issue that is exacerbated in highly modified urban environments. Despite this, critical ecological knowledge is currently lacking for many wetland-dependent taxa, such as insectivorous bats, which can persist in urban areas if their habitats are managed appropriately. Here, we use a novel paired landscape approach to investigate the role of wetlands in urban bat conservation and examine local and landscape factors driving bat species richness and activity. We acoustically monitored bat activity at 58 urban wetlands and 35 nonwetland sites (ecologically similar sites without free-standing water) in the greater Melbourne area, southeastern Australia. We analyzed bat species richness and activity patterns using generalized linear mixed-effects models. We found that the presence of water in urban Melbourne was an important driver of bat species richness and activity at a landscape scale. Increasing distance to bushland and increasing levels of heavy metal pollution within the waterbody also negatively influenced bat richness and individual species activity. Areas with high levels of artificial night light had reduced bat species richness, and reduced activity for all species except those adapted to urban areas, such as the White-striped free-tailed bat (Austronomus australis). Increased surrounding tree cover and wetland size had a positive effect on bat species richness. Our findings indicate that wetlands form critical habitats for insectivorous bats in urban environments. Large, unlit, and unpolluted wetlands flanked by high tree cover in close proximity to bushland contribute most to the richness of the bat community. Our findings clarify the role of wetlands for insectivorous bats in urban areas and will also allow for the preservation, construction, and management of wetlands

An Assessment of the Relationship between Urban Air Quality and Environmental Urban Factors in Urban Regeneration Areas

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Yakup Egercioglu

2016-06-01

Full Text Available Urban air pollution has been increasing due to ever increasing population, rapid urbanization, industrialization, energy usage, traffic density. The purpose of the study is to examine the relation between urban air quality and urban environmental factors in urban regeneration areas. Two common air polluters (SO2 and PM10 are considered in the study. The data are collected for Cigli district, including the level of air pollutants, the local natural gas service lines and planning decisions for the years between 2007 and 2011. According to the examinations, urban environmental factors and planning decisions affect the urban air quality in urban regeneration areas.

PBDEs and other POPs in urban birds of prey partly explained by trophic level and carbon source

Energy Technology Data Exchange (ETDEWEB)

Elliott, John E. [Environment Canada, Science & Technology Branch, Pacific Wildlife Research Centre, Delta, British Columbia V4K 3N2 (Canada); Department of Biological Science, Simon Fraser University, Burnaby, BC V5A 1S6 (Canada); Brogan, Jason [Department of Biological Science, Simon Fraser University, Burnaby, BC V5A 1S6 (Canada); Lee, Sandi L. [Environment Canada, Science & Technology Branch, Pacific Wildlife Research Centre, Delta, British Columbia V4K 3N2 (Canada); Drouillard, Ken G. [Great Lakes Institute for Environmental Research, University of Windsor, Windsor, ON N9B 3P4 (Canada); Elliott, Kyle H. [Department of Natural Resource Sciences, McGill University, Ste. Anne de Bellevue, Quebec H9X 3V9 (Canada)

2015-08-15

As urban sprawl and agricultural intensification continue to invade prime wildlife habitat, some animals, even apex predators, are managing to adapt to this new environment. Chemical pollution is one of many stressors that wildlife encounter in urban environments. Predators are particularly sensitive to persistent chemical pollutants because they feed at a high trophic level where such pollution is biomagnified. To examine levels of pollution in urban birds of prey in the Lower Mainland region of British Columbia, Canada, we analyzed persistent organic contaminants in adult birds found dead of trauma injury. The hepatic geometric mean concentration of sum polybrominated diphenyl ethers (∑PBDEs) in 13 Cooper's hawks (Accipiter cooperii) from Greater Vancouver was 1873 ng/g (lipid weight) with one bird reaching 197,000 ng/g lipid weight, the highest exposure reported to date for a wild bird. Concentrations of ∑PBDEs, ∑PCBs (polychlorinated biphenyls) and, surprisingly, cyclodiene insecticides were greatest in the urban environment while those of DDE (1,1-dichloroethylene bis[p-chlorophenyl) were highest in a region of intensive agriculture. The level of most chlorinated and brominated contaminants increased with trophic level (δ{sup 15}N). The concentrations of some contaminants, PBDEs in particular, in these birds of prey may have some toxicological consequences. Apex predators in urban environments continue to be exposed to elevated concentrations of legacy pollutants as well as more recent brominated pollutants. - Highlights: • As urban areas expand, many animal species are adapting and invading urban areas. • Urban colonists encounter many new stressors, especially chemical pollution. • Urban birds of prey in Canada had high levels of brominated flame retardants (PBDEs). • One individual had the highest level of PBDEs ever recorded for wildlife. • Such high levels may have had toxicological implications.

PBDEs and other POPs in urban birds of prey partly explained by trophic level and carbon source

International Nuclear Information System (INIS)

Elliott, John E.; Brogan, Jason; Lee, Sandi L.; Drouillard, Ken G.; Elliott, Kyle H.

2015-01-01

As urban sprawl and agricultural intensification continue to invade prime wildlife habitat, some animals, even apex predators, are managing to adapt to this new environment. Chemical pollution is one of many stressors that wildlife encounter in urban environments. Predators are particularly sensitive to persistent chemical pollutants because they feed at a high trophic level where such pollution is biomagnified. To examine levels of pollution in urban birds of prey in the Lower Mainland region of British Columbia, Canada, we analyzed persistent organic contaminants in adult birds found dead of trauma injury. The hepatic geometric mean concentration of sum polybrominated diphenyl ethers (∑PBDEs) in 13 Cooper's hawks (Accipiter cooperii) from Greater Vancouver was 1873 ng/g (lipid weight) with one bird reaching 197,000 ng/g lipid weight, the highest exposure reported to date for a wild bird. Concentrations of ∑PBDEs, ∑PCBs (polychlorinated biphenyls) and, surprisingly, cyclodiene insecticides were greatest in the urban environment while those of DDE (1,1-dichloroethylene bis[p-chlorophenyl) were highest in a region of intensive agriculture. The level of most chlorinated and brominated contaminants increased with trophic level (δ 15 N). The concentrations of some contaminants, PBDEs in particular, in these birds of prey may have some toxicological consequences. Apex predators in urban environments continue to be exposed to elevated concentrations of legacy pollutants as well as more recent brominated pollutants. - Highlights: • As urban areas expand, many animal species are adapting and invading urban areas. • Urban colonists encounter many new stressors, especially chemical pollution. • Urban birds of prey in Canada had high levels of brominated flame retardants (PBDEs). • One individual had the highest level of PBDEs ever recorded for wildlife. • Such high levels may have had toxicological implications

URBAN FEATURES AND ENERGY CONSUMPTION AT LOCAL LEVEL

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Ali Soltani

2012-12-01

Full Text Available There has been a growing interest in discovering the human effects on the environment and energy consumption in recent decades. It is estimated that the share of energy consumed in transportation and housing systems are around 20 and 30 percent of total energy consumption respectively. Furthermore, the residential greenhouse emissions depend on urban form and structure. This paper explores the effects of urban features on residential energy consumption at neighborhood level using data collected through household questionnaire (n=140. Two residential districts in metropolitan Shiraz, south of Iran, were selected as case study areas. Different features of two areas were compared including building density, typology, housing location, parcel size, floor area and construction materials. Ordinary linear regression was used to discover the impact of explanatory variables on energy consumption. It was found that some physical variables such as parcel size, setback and number of floors played significant roles in explaining the variances exist in energy use level. The results can be used by governmental agencies to modify land use policies and subdivision rules in hope of saving energy and achieving a sustainable community.

Dynamic impact of urbanization, economic growth, energy consumption, and trade openness on CO 2 emissions in Nigeria.

Science.gov (United States)

Ali, Hamisu Sadi; Law, Siong Hook; Zannah, Talha Ibrahim

2016-06-01

The objective of this paper is to examine the dynamic impact of urbanization, economic growth, energy consumption, and trade openness on CO 2 emissions in Nigeria based on autoregressive distributed lags (ARDL) approach for the period of 1971-2011. The result shows that variables were cointegrated as null hypothesis was rejected at 1 % level of significance. The coefficients of long-run result reveal that urbanization does not have any significant impact on CO 2 emissions in Nigeria, economic growth, and energy consumption has a positive and significant impact on CO 2 emissions. However, trade openness has negative and significant impact on CO 2 emissions. Consumption of energy is among the main determinant of CO 2 emissions which is directly linked to the level of income. Despite the high level of urbanization in the country, consumption of energy still remains low due to lower income of the majority populace and this might be among the reasons why urbanization does not influence emissions of CO 2 in the country. Initiating more open economy policies will be welcoming in the Nigerian economy as the openness leads to the reduction of pollutants from the environment particularly CO 2 emissions which is the major gases that deteriorate physical environment.

Evaluation of OMI operational standard NO2 column retrievals using in situ and surface-based NO2 observations

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L. N. Lamsal

2014-11-01

Full Text Available We assess the standard operational nitrogen dioxide (NO2 data product (OMNO2, version 2.1 retrieved from the Ozone Monitoring Instrument (OMI onboard NASA's Aura satellite using a combination of aircraft and surface in~situ measurements as well as ground-based column measurements at several locations and a bottom-up NOx emission inventory over the continental US. Despite considerable sampling differences, NO2 vertical column densities from OMI are modestly correlated (r = 0.3–0.8 with in situ measurements of tropospheric NO2 from aircraft, ground-based observations of NO2 columns from MAX-DOAS and Pandora instruments, in situ surface NO2 measurements from photolytic converter instruments, and a bottom-up NOx emission inventory. Overall, OMI retrievals tend to be lower in urban regions and higher in remote areas, but generally agree with other measurements to within ± 20%. No consistent seasonal bias is evident. Contrasting results between different data sets reveal complexities behind NO2 validation. Since validation data sets are scarce and are limited in space and time, validation of the global product is still limited in scope by spatial and temporal coverage and retrieval conditions. Monthly mean vertical NO2 profile shapes from the Global Modeling Initiative (GMI chemistry-transport model (CTM used in the OMI retrievals are highly consistent with in situ aircraft measurements, but these measured profiles exhibit considerable day-to-day variation, affecting the retrieved daily NO2 columns by up to 40%. This assessment of OMI tropospheric NO2 columns, together with the comparison of OMI-retrieved and model-simulated NO2 columns, could offer diagnostic evaluation of the model.

Urban-Rural Differences Explain the Association between Serum 25-Hydroxyvitamin D Level and Insulin Resistance in Korea

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Bo Mi Song

2014-12-01

Full Text Available An increasing number of studies report associations between low serum 25-hydroxyvitamin D [25(OHD] level and insulin resistance; however, whether low vitamin D levels directly contribute to increased insulin resistance is unclear. We investigated the impact of residential area on the association between 25(OHD and insulin resistance in elderly Koreans. Using data from the Korean Urban Rural Elderly study, we conducted cross-sectional analyses in 1628 participants (505 men and 1123 women. Serum 25(OHD was analyzed as both continuous and categorized variables. Homeostasis model assessment for insulin resistance (HOMA-IR was calculated using fasting blood glucose and insulin levels. In men, 25(OHD level was inversely associated with HOMA-IR (standardized β = −0.133, p < 0.001 after adjustment for age, body mass index, waist circumference, smoking, alcohol intake, exercise, and study year. However, we noted significant urban-rural differences in 25(OHD level (43.4 versus 65.6 nmol/L; p < 0.001 and HOMA-IR (1.2 versus 0.8 mmol·pmol/L2; p < 0.001. When we additionally adjusted for residential area, the association between 25(OHD and HOMA-IR was attenuated (standardized β = −0.063, p = 0.115. In women, the association between 25(OHD and HOMA-IR was not significant before or after adjustment for residential area. Environmental or lifestyle differences in urban and rural areas may largely explain the inverse association between serum 25(OHD and insulin resistance.

Urban renewal based wind environment at pedestrian level in high-density and high-rise urban areas in Sai Ying Pun, Hong Kong

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Yao, J. W.; Zheng, J. Y.; Zhao, Y.; Shao, Y. H.; Yuan, F.

2017-11-01

In high-density and high-rise urban areas, pedestrian level winds contribute to improve comfort, safety and diffusion of heat in urban areas. Outdoor wind study is extremely vital and a prerequisite in high-density cities considering that the immediate pedestrian level wind environment is fundamentally impacted by the presence of a series of high-rise buildings. In this paper, the research site of Sai Ying Pun in Hong Kong will be analysed in terms of geography, climate and urban morphology, while the surrounding natural ventilation has also been simulated by the wind tunnel experiment Computational Fluid Dynamics (CFD). It has found that, the existing problems in this district are the contradiction between planning control and commercial interests, which means some areas around tall buildings are not benefit to the residents because of the unhealthy wind environment. Therefore, some recommendation of urban renewal strategy has been provided.

Quantifying air pollution attenuation within urban parks: An experimental approach in Shanghai, China

International Nuclear Information System (INIS)

Yin Shan; Shen Zhemin; Zhou Pisheng; Zou Xiaodong; Che Shengquan; Wang Wenhua

2011-01-01

Parks with various types of vegetations played an important role in ameliorating air quality in urban areas. However, the attenuation effect of urban vegetation on levels of air pollution was rarely been experimentally estimated. This study, using seasonal monitoring data of total suspended particles (TSP), sulfur dioxide (SO 2 ) and nitrogen dioxide (NO 2 ) from six parks in Pudong District, Shanghai, China, demonstrated vegetations in parks can remove large amount of airborne pollutants. In addition, crown volume coverage (CVC) was introduced to characterize vegetation conditions in parks and a mixed-effects model indicated that CVC and the pollution diffusion distance were key predictors influencing pollutants removal rate. Therefore, it could be estimated by regression analysis that in summer, urban vegetations in Pudong District could contribute to 9.1% of TSP removal, 5.3% of SO 2 and 2.6% of NO 2 . The results could be considered for a better park planning and improving air quality. - Highlights: → We examined markedly air pollution decline in urban vegetation patches by field experiments. → Crown volume coverage (CVC) served to characterize vegetation condition among different species. → CVC and pollutants diffusion distance were key predictors affecting air pollution attenuation within parks. - Crown volume coverage (CVC) and pollutants diffusion distance had been proved as key predictors influencing attenuation effect on levels of air pollutants in urban parks.

Quantifying air pollution attenuation within urban parks: An experimental approach in Shanghai, China

Energy Technology Data Exchange (ETDEWEB)

Yin Shan [School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Rd, Shanghai 200240 (China); Institute of Urban and Regional Development, University of California, 316 Wurster Hall, Berkeley, CA 94720 (United States); Shen Zhemin [School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Rd, Shanghai 200240 (China); Zhou Pisheng [School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Rd, Shanghai 200240 (China); Zou Xiaodong [School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Rd, Shanghai 200240 (China); Che Shengquan [School of Agriculture and Biology, Shanghai Jiao Tong University, 800 Dongchuan Rd, Shanghai 200240 (China); Wang Wenhua, E-mail: whwang@sjtu.edu.cn [School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Rd, Shanghai 200240 (China)

2011-08-15

Parks with various types of vegetations played an important role in ameliorating air quality in urban areas. However, the attenuation effect of urban vegetation on levels of air pollution was rarely been experimentally estimated. This study, using seasonal monitoring data of total suspended particles (TSP), sulfur dioxide (SO{sub 2}) and nitrogen dioxide (NO{sub 2}) from six parks in Pudong District, Shanghai, China, demonstrated vegetations in parks can remove large amount of airborne pollutants. In addition, crown volume coverage (CVC) was introduced to characterize vegetation conditions in parks and a mixed-effects model indicated that CVC and the pollution diffusion distance were key predictors influencing pollutants removal rate. Therefore, it could be estimated by regression analysis that in summer, urban vegetations in Pudong District could contribute to 9.1% of TSP removal, 5.3% of SO{sub 2} and 2.6% of NO{sub 2}. The results could be considered for a better park planning and improving air quality. - Highlights: > We examined markedly air pollution decline in urban vegetation patches by field experiments. > Crown volume coverage (CVC) served to characterize vegetation condition among different species. > CVC and pollutants diffusion distance were key predictors affecting air pollution attenuation within parks. - Crown volume coverage (CVC) and pollutants diffusion distance had been proved as key predictors influencing attenuation effect on levels of air pollutants in urban parks.

Dynamics of Urbanization Levels in China from 1992 to 2012: Perspective from DMSP/OLS Nighttime Light Data

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Bin Gao

2015-02-01

Full Text Available The authenticity and reliability of urbanization levels measured by different indicators in China have not reached a consensus, which may impede our understanding of the process of urbanization and its impacts on the environment. The objective of this study was to describe a reliable method of estimating urbanization level based on the Operational Line-scan System (OLS on the Defense Meteorological Satellite Program (DMSP nighttime light data and to analyze the dynamics of urbanization levels in China from 1992 to 2012. We calculated the comprehensive urbanization level at the national, provincial, and county scales using a compounded night light index (CNLI and compared the change rate of CNLI with those of the other two conventional urbanization level indicators, proportion of the nonagricultural population and proportion of built-up area. Our results showed that CNLI derived from the DMSP/OLS data set provided a relatively reliable and accurate measure of the comprehensive urbanization level in China. During the last two decades, China has experienced continued and rapid urbanization with large regional variations. The CNLI increased 3.12 times, from 1.72 × 10−3 to 7.09 × 10−3. The annual increases of CNLI in eastern provinces were much faster than those in western provinces. In addition, we found that the rates of change in these three indicators were consistent for most provinces with the exception of the four municipalities (Beijing, Tianjin, Shanghai, and Chongqing and a few eastern coastal provinces (Jiangsu, Zhejiang, Fujian, and Guangdong. Because the imbalance among population growth, urban expansion and socioeconomic development may affect cities’ sustainable development, we should pay more attention to these regions with large disparities between different indicators.

Personal exposure to PM2.5, black smoke and NO2 in Copenhagen: relationship to bedroom and outdoor concentrations covering seasonal variation.

Science.gov (United States)

Sørensen, Mette; Loft, Steffen; Andersen, Helle Vibeke; Raaschou-Nielsen, Ole; Skovgaard, Lene Theil; Knudsen, Lisbeth E; Nielsen, Ivan V; Hertel, Ole

2005-09-01

Epidemiological studies have found negative associations between human health and particulate matter in urban air. In most studies outdoor monitoring of urban background has been used to assess exposure. In a field study, personal exposure as well as bedroom, front door and background concentrations of PM(2.5), black smoke (BS), and nitrogen dioxide (NO(2)) were measured during 2-day periods in 30 subjects (20-33 years old) living and studying in central parts of Copenhagen. The measurements were repeated in the four seasons. Information on indoor exposure sources such as environmental tobacco smoke (ETS) and burning of candles was collected by questionnaires. The personal exposure, the bedroom concentration and the front door concentration was set as outcome variable in separate models and analysed by mixed effect model regression methodology, regarding subject levels as a random factor. Seasons were defined as a dichotomised grouping of outdoor temperature (above and below 8 degrees C). For NO(2) there was a significant association between personal exposure and both the bedroom, the front door and the background concentrations, whereas for PM(2.5) and BS only the bedroom and the front door concentrations, and not the background concentration, were significantly associated to the personal exposure. The bedroom concentration was the strongest predictor of all three pollution measurements. The association between the bedroom and front door concentrations was significant for all three measurements, and the association between the front door and the background concentrations was significant for PM(2.5) and NO(2), but not for BS, indicating greater spatial variation for BS than for PM(2.5) and NO(2). For NO(2), the relationship between the personal exposure and the front door concentration was dependent upon the "season", with a stronger association in the warm season compared with the cold season, and for PM(2.5) and BS the same tendency was seen. Time exposed to

Urban flood risk warning under rapid urbanization.

Science.gov (United States)

Chen, Yangbo; Zhou, Haolan; Zhang, Hui; Du, Guoming; Zhou, Jinhui

2015-05-01

In the past decades, China has observed rapid urbanization, the nation's urban population reached 50% in 2000, and is still in steady increase. Rapid urbanization in China has an adverse impact on urban hydrological processes, particularly in increasing the urban flood risks and causing serious urban flooding losses. Urban flooding also increases health risks such as causing epidemic disease break out, polluting drinking water and damaging the living environment. In the highly urbanized area, non-engineering measurement is the main way for managing urban flood risk, such as flood risk warning. There is no mature method and pilot study for urban flood risk warning, the purpose of this study is to propose the urban flood risk warning method for the rapidly urbanized Chinese cities. This paper first presented an urban flood forecasting model, which produces urban flood inundation index for urban flood risk warning. The model has 5 modules. The drainage system and grid dividing module divides the whole city terrain into drainage systems according to its first-order river system, and delineates the drainage system into grids based on the spatial structure with irregular gridding technique; the precipitation assimilation module assimilates precipitation for every grids which is used as the model input, which could either be the radar based precipitation estimation or interpolated one from rain gauges; runoff production module classifies the surface into pervious and impervious surface, and employs different methods to calculate the runoff respectively; surface runoff routing module routes the surface runoff and determines the inundation index. The routing on surface grid is calculated according to the two dimensional shallow water unsteady flow algorithm, the routing on land channel and special channel is calculated according to the one dimensional unsteady flow algorithm. This paper then proposed the urban flood risk warning method that is called DPSIR model based

Differences in the Fitness Levels of Urban and Rural Middle School Students in Croatia

Science.gov (United States)

Novak, Dario; Bernstein, Eve R.; Podnar, Hrvoje; Vozzolo, Yolanda

2015-01-01

Background: It is known that suburban youth are more fit than urban youth in Croatia. Method: Differences (p < 0.05) in fitness levels and motor abilities of 9,164 (F = 4,671, M = 4,493) Croatian children (age range: 11-14 years) from urban (F = 1,380, M = 1,268), mixed rural-urban (F = 274, M = 289), and rural (F = 3017, M = 2936) areas were…

Assessment of ambient noise levels in the urban residential streets of Eastern Alexandria, Egypt.

Science.gov (United States)

Zaki, Gehan R

2012-12-01

Street of Alexandria have numerous unplanned, mixed, and noisy activities that may interfere with public health and comfort. The aim of this study was to assess A-weighted ambient noise levels in urban residential streets of Eastern Alexandria, Egypt, from September 2010 to January 2011, with the objective of recommending corrective actions to minimize high noise levels. A descriptive cross-sectional study was carried out, in which A-weighted ambient noise levels were measured on the basis of 24-h periods, using Ono sokki la-5120--precision integrating sound level meter, from September 2010 to January 2011. The measurements were taken on three streets, which were selected using stratified random sampling. Seven measurement sites, along the three streets under study, were selected by site visits according to predetermined criteria. A-weighted ambient noise levels (LAeq) were the highest [70.7 (24.2) dB] on high-traffic-density and high-human-activity streets followed by streets with moderate and low traffic density and human activity [67.5 (31.3) and 62.8 (38.2) dB], respectively. It varied significantly depending on means of transportation (road traffic, train, and/or tram) and human activities (parking lots, shops, and/or street merchants). The A-weighted ambient noise levels on urban residential streets of Eastern Alexandria, Egypt, exceeded the Egyptian National Standards during the three periods of the day (daytime, evening, and night), except in some relatively quiet locations during the night. Consequently, remedial actions to reduce noise levels were recommended.

Urban air pollution induces micronuclei in peripheral erythrocytes of mice in vivo

International Nuclear Information System (INIS)

Soares, S.R.C.; Bueno-Guimaraes, H.M.; Ferreira, C.M.; Rivero, D.H.R.F.; Castro, I. de; Garcia, M.L.B.; Saldiva, P.H.N.

2003-01-01

In this study, we explored the role of chronic exposure to urban air pollution in causing DNA damage (micronuclei frequency in peripheral erythrocytes) in rodents in vivo. Mice (n=20) were exposed to the urban atmosphere of Sao Paulo for 120 days (February to June 1999) and compared to animals (n=20) maintained in the countryside (Atibaia) for the same period. Daily levels of inhalable particles (PM10), CO, NO 2 , and SO 2 , were available for Sao Paulo. Occasional measurements of CO and O 3 were made in Atibaia, showing negligible levels of pollution in the area. The frequency of micronuclei (repeated-measures ANOVA) increased with aging, the highest values obtained for the 90th day of experiment (P 2 (P<0.001), and PM10 (P<0.001). Our results support the concept that urban levels of air pollution may cause somatic mutations

Levels of metals in blood samples from Mallards (Anas platyrhynchos) from urban areas in Poland

International Nuclear Information System (INIS)

Binkowski, Łukasz J.; Meissner, Włodzimierz

2013-01-01

In this paper we present the studies conducted on blood samples taken from Mallards (Anas platyrhynchos). Birds were captured for ringing purposes (n = 43) in two small and two big towns (including highly urbanized areas). For comparison samples of blood from birds shot on fish ponds were used (n = 26). Based on the body mass all sampled individuals can be assessed as being in good condition. Levels of cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb) and zinc (Zn) in blood samples were measured with AAS. Concentrations of metals did not differ statistically between sexes and made up a following order: Fe > Zn > Cu > Cr ≈ Ni > Pb > Cd. Mallards from towns revealed lower concentrations of Zn and Cu but higher concentration of Fe. There was no difference in exposition to Pb between birds from towns and fish ponds. -- Highlights: •Concentrations of seven metals were measured in blood of Mallards. •Birds represent different kind of areas: urban (towns) and non-urban ones (fish ponds). •Concentrations of studied metals made up a following order: Fe > Zn > Cu > Cr ≈ Ni > Pb > Cd. •Birds from towns revealed higher amount of Fe and lower concentrations of Zn and Cu. •There was no difference in exposition to Pb between birds from towns and fish ponds. -- Exposition to iron is higher on industrialized areas in towns, but exposition to zinc and copper on such areas is lower in comparison to country fish ponds

: Urban design, urban project, urban art, urban composition ... a question of vocabulary?

OpenAIRE

Pinson , Daniel

2014-01-01

Actes à paraître; International audience; The term "urbanism" of Pierre Clerget (1910) put the mess in the practice and the formations in France. Urban planning is thus, on the academic level, a coexistence of disciplinary approaches, which does not help to a multidisciplinary urban training. Thinking about "urban design", after beautifull city, urban composition, or alongside the urban project and other territorial approaches can help to see more clearly in town planning.; Le terme « urbanis...

Real-time monitoring of nitric oxide (NO) and pO2 levels under ischemic conditions associated with small bowel ischemia/reperfusion injury using selective electrodes for NO and oxygen molecules.

Science.gov (United States)

Watanabe, T; Owada, S; Kobayashi, H; Ishiuchi, A; Nakano, H; Asakuta, T; Shimamura, T; Asano, T; Koizumi, S; Jinnouchi, Y; Katayama, M; Kamibayasi, M; Murakami, E; Otsubo, T

2007-12-01

The present study demonstrated the feasibility of monitoring nitric oxide (NO) and pO2 levels under ischemic conditions associated with small bowel ischemia/reperfusion (I/R) injury through the use of selective electrodes for NO and oxygen molecules. NO levels gradually increased during ischemia. When reperfusion was started, the NO level decreased suddenly and returned to pre-ischemia values within 10 minutes. After clamping, pO2 decreased rapidly. When reperfusion was started, pO2 increased suddenly, returning to pre-ischemia values within 10 minutes. We concluded that it is feasible to monitor NO and pO2 levels under ischemic conditions of small bowel I/R injury through the use of electrodes selective for NO and oxygen molecules.

Urban CO2 emissions in China: Spatial boundary and performance comparison

International Nuclear Information System (INIS)

Cai, Bofeng; Zhang, Lixiao

2014-01-01

Different names/concepts and therefore different spatial boundaries for cities in China are responsible for the conflicting and confusing results associated with urban CO 2 emissions accounting. In this study, four types of urban boundaries, i.e., city administrative boundary (UB 1 ), city district boundary (UB 2 ), city built-up area (UB 3 ) and urban proper (UB 4 ), were identified and defined. Tianjin was subsequently selected as the case city to illustrate the different performances of CO 2 emissions with respect to these four boundaries using a 1-km grid dataset built bottom-up by point-emission sources. Different urban boundaries can induce a difference in CO 2 emissions as large as 654%. UB 1 and UB 2 are not the appropriate proxies for urban boundaries in the analysis of urban CO 2 emissions, although UB 1 is a widely adopted boundary. UB 3 is a good representative of city clusters and urban sprawl in a certain region, whereas UB 4 is the appropriate system boundary for such issues as urban CO 2 emissions in light of landscape characteristics and pertinent human activities, as well as the comparability to counterparts in developed countries. These results provide sound policy implications for the improvement of urban energy management and carbon emission abatement in China. - highlights: • Four types of urban boundaries in China were clarified and defined. • Different urban boundaries will induce deviation in CO 2 emissions as large as 654%. • The UB 4 stands for appropriate urban boundary for urban CO 2 emissions analysis. • Gridded data proves to be supplementary tools for urban CO 2 emissions accounting

Determination of spatial continuity of soil lead levels in an urban residential neighborhood

Energy Technology Data Exchange (ETDEWEB)

Shinn, N.J.; Bing-Canar, J.; Cailas, M.; Peneff, N.; Binns, H.J.

2000-01-01

This study uses geostatistical techniques to model and estimate soil lead levels in an urban, residential neighborhood. Sixty-two composite soil samples in a four-block area of brick and stone homes were obtained. The spatial continuity of soil lead levels was modeled with a semi-variogram, which was then used to estimate lead levels at unsampled locations, a process called kriging. Because soil lead levels were spatially correlated, it is likely that a nonrandom process generated the lead distribution found. This finding signifies the existence of lead sources which were tentatively identified on historical maps of the area and from past traffic volume patterns. The distribution of kriged estimates of soil lead levels provides an explanatory tool for exploring and identifying potential sources and may be useful for targeting urban soil abatement efforts.

Lead contamination and transfer in urban environmental compartments analyzed by lead levels and isotopic compositions

International Nuclear Information System (INIS)

Hu, Xin; Sun, Yuanyuan; Ding, Zhuhong; Zhang, Yun; Wu, Jichun; Lian, Hongzhen; Wang, Tijian

2014-01-01

Lead levels and isotopic compositions in atmospheric particles (TSP and PM 2.5 ), street dust and surface soil collected from Nanjing, a mega city in China, were analyzed to investigate the contamination and the transfer of lead in urban environmental compartments. The lead contents in TSP and PM 2.5 are significantly higher than them in the surface soil and street dust (p  206 Pb/ 207 Pb vs. 208 Pb/ 206 Pb and 206 Pb/ 207 Pb vs. 1/Pb imply that the street dust and atmospheric particles (TSP and PM 2.5 ) have very similar lead sources. Coal emissions and smelting activities may be the important lead sources for street dust and atmospheric particles (TSP and PM 2.5 ), while the deposition of airborne lead is an important lead source for urban surface soil. - Highlights: • Lead levels and isotope ratios in atmospheric particles, street dust and surface soil. • Significant enrichment of lead in atmospheric particles was observed. • Street dust and atmospheric particles have similar lead sources. • Endmembers of soil lead differ from street dust and atmospheric particles. • Airborne lead poses the main risks to unban environmental quality. - Transfer of airborne particle bound lead into street dust and surface soil in unban environmental based on lead levels and isotopic compositions

Levels and Speciation of Platinum in Size-Fractionated Atmospheric Aerosol in Urban and Rural Sites across Europe

Science.gov (United States)

Shafer, Martin; Antkiewicz, Dagmara; Overdier, Joel; Schauer, James

2016-04-01

In this study we characterized the levels and speciation of platinum in a unique set of size-resolved atmospheric aerosol (PM) samples obtained from urban environments across Europe. From April-July 2012 we collected PM from roadside canyon, roadside motorway, and background urban sites in each of six European cities (Amsterdam, Frankfurt, London, Milan, Stockholm, and Thessaloniki). A Hi-Vol sampler was used to collect PM in three size classes (>PM7, PM7-PM3, PM3) and characterized for total platinum, soluble platinum (in a suite of physiologically relevant fluids - lung fluid (ALF), Gambles saline, 0.07M HCl, and MQ) and speciated forms (colloidal and anionic) within the soluble fractions. In addition we measured 50 other elements by SF-ICPMS, soluble ions by IC, and soluble organic carbon in the PM. Order-of-magnitude differences in air concentrations of total platinum were observed between urban sites, ranging from 4 to over 45 pg/m3; with a median level of 6 pg/m3. When platinum concentrations are normalized to PM mass the cross Europe and site-to-site variability was substantially reduced - a 3-fold variation from 200 to 600 ng/g was observed. Roadside canyon sites in London, Stockholm and Thessaloniki exhibited the highest concentrations; however levels at urban background sites were remarkably similar across the cities. Relatively consistent and low concentrations (1 to 2 pg/m3) of total platinum were observed at rural background sites across Europe. The contribution of coarse particles (>7 micron and 7-3 micron) to air concentrations of total platinum was very significant (>35% at nearly all sites). Soluble platinum fractions ranged from 2 to 6% (MQ to HCl) in rural background sites to 5 to 20% (MQ to HCl) in roadway canyon sites in London and Thessaloniki; with the extractable platinum fractions a strong function of pH. With the exception of urban canyon sites in London and Thessaloniki, soluble platinum concentrations in the fine aerosol (PM3) were all

Effects of Compact Urban Development on Air Pollution: Empirical Evidence from Korea

Directory of Open Access Journals (Sweden)

Hee-Sun Cho

2014-09-01

Full Text Available This study investigates the effects of compact urban development on air pollution, taking into account both the spatial distribution of pollutants resulting from an increase in inner urban densities and the dispersion of pollutants associated with an increase in outer green open spaces. The empirical analysis is based upon a panel data model covering 17 cities in Korea from 1996–2009; this approach is used because urban air pollution is influenced by spatial and temporal changes. Measuring the air pollution level by distance from city centers demonstrates that the spatial concentration of emission sources does not necessarily increase air pollution levels. The two-way fixed effects model, which is employed to control both individual (regional and time effects, shows that SO2 decreases as the proportion of green area increases, while a rise in net density leads to an increase of NO2. Both effects are observed in the case of CO dispersion by green area as well as emission source concentration by high densities. Therefore, there is no clear impact of compact urban development on air quality, which is instead related to pollutant-specific characteristics and the emission source.

Modeling annual benzene, toluene, NO2, and soot concentrations on the basis of road traffic characteristics

International Nuclear Information System (INIS)

Carr, David; Ehrenstein, Ondine von; Weiland, Stephan; Wagner, Claudia; Wellie, Oliver; Nicolai, Thomas; Mutius, Erika von

2002-01-01

The investigation of potential adverse health effects of urban traffic-related air pollution is hampered by difficulties encountered with exposure assessment. Usually public measuring sites are few and thereby do not adequately describe spatial variation of pollutant levels over an urban area. In turn, individual monitoring of pollution exposure among study subjects is laborious and expensive. We therefore investigated whether traffic characteristics can be used to adequately predict benzene, NO 2 , and soot concentrations at individual addresses of study subjects in the city area of Munich, Germany. For all road segments with expected traffic volumes of at least 4000 vehicles a day (n=1840), all vehicles were counted manually or a single weekday in 1995. The proportion of vehicles in 'stop-go' mode, n estimate of traffic jam, was determined. Furthermore, annual concentrations of benzene, NO 2 , and soot from 18 high-concentration sites means: 8.7, 65.8, and 12.9 μg/m 3 , respectively) and from 16 school sites with moderate concentrations (means: 2.6, 32.2, and 5.7 μg/m 3 , respectively) were measured from 1996 to 1998. Statistical analysis of the data was performed using components of two different statistical models recently used to predict air pollution levels in comparable settings. Two traffic characteristics, traffic volume and traffic jam percentage, adequately described air pollutant concentrations (R 2 : 0.76-0.80, P=0.0001). This study shows that air pollutant concentrations can be accurately predicted by two traffic characteristics and that these models compare favorably with other more complex models in the literature

[Urbanization mechanisms in bird species: population systems transformations or adaptations at the individual level?].

Science.gov (United States)

Fridman, V S; Eremkin, G S; Zakharova-Kubareva, N Iu

2008-01-01

The present research deals with urbanization of wild bird and mammal species. Forms and mechanisms of population steadiness in the urban landscape have been examined. The urbanization process turned out to be a directed change of the population system forming de novo in the urbolandscape leading to a sustainable organization peculiar for the particular environment. The population organization of different types in urbolandscape is found to provide its stability under conditions of directed and fast changes accompanied with instability and heterogenous structure of habitats. It is shown that the same type of population organization meets the corresponding demands among different species settling in the urban environment. Its features are "openness" and "flowage" of the groups, far order of settlement levels and other units of population system, constant movements of the individuals between the groups as a respond to the signals of urboenvironment significant changes. The "urban" variant of the population system organization turns out to be opposite to that of the same species in the non-urban habitats. After formation of the urban types by the species and successful developing of the town, the urban population becomes separated from the maternal local population and begins to exist independently in the urban landscape. The variety of adaptation aberrations in ecology, behavior, and mode of life of urban birds is the population system stability function in the urban landscape and is not a results of individual selection. It is shown that the urbanization process of the species goes firstly on the population level being the system structure transformation developed by the species towards the most stable state in the town (city) territory. Only after the appearance of stable urban population, the urban individuals show the rapid growth of different changes in ecology, behavior, mode of life that was traditionally described by naturalists as species adaptation to the

Winter Distribution of On-road NO2 Concentration in Hong Kong

Science.gov (United States)

Zhu, Y.; Chan, K. L.; Boll, J.; Schütt, A. M. N.; Lipkowitsch, I.; Wenig, M.

2017-12-01

In this study, we investigated the spatial distribution of on road NO2 concentration using Cavity-Enhanced Differential Optical Absorption Spectroscopy (DOAS). We performed two measurement campaigns in winter 2010 and 2017. Air pollution is a severe problem for many big cities, especially in Asia. Traffic emission is the primary source of urban pollutants. As Hong Kong is one of the most densely populated cities in the world, many inhabitants are exposed to accumulated pollutants in street canyons. Our mobile measurements were performed for a week in December, 2010 and March, 2017. Additionally, long term air pollution data measured by a long-path DOAS (LP-DOAS) and the Environment Protection Department (EPD) air quality monitoring network were used to investigate the long term trend and seasonal variations of atmospheric NO2 in Hong Kong.The experiment setup and preliminary results of mobile measurements are presented. The measurements were performed along a fixed route which covers most of the urban area. We assembled a NO2 concentration map 2 to 3 times per day in order to cover both morning and evening rush hours. In order to construct a consistent map, we use coinciding LP-DOAS NO2 data to correct for the diurnal cycle. Furthermore, the spatial and temporal distribution of NO2 changes with the day of the week. Traffic load is highly dependent on human activities which typically fall into a 7 days cycle. Therefore, we have analyzed the weekly pattern of on road NO2 distribution to see the differences between anthropogenic emissions during weekdays and weekend.

A new simplified NO/NO2 conversion model under consideration of direct NO2-emissions

Directory of Open Access Journals (Sweden)

I. Düring

2011-02-01

Full Text Available Although many German monitoring sites report declines of NOx concentrations, NO2-concentrations actually stagnate or even increase quite often. Various analyses have identified the altered compositions of nitrogen oxides (NO2/NOx-ratio emitted by motor vehicles (resulting in an increase of primary NO2-emissions as well as the chemical environmental conditions (mainly ground level ozone as the main causes. The chemical conversion of NO to NO2 is often parameterized in dispersion calculations of exhaust emissions. A widely applied conversion model is the so-called Romberg approach from 1996. However, the Romberg approach has to be re-evaluated to accommodate the above-mentioned conditions. This article presents an adjustment to the Romberg approach in accordance with the measured data from 2000 to 2006, taking into consideration substantially higher NO2/NOx-ratios especially for higher NOx-concentrations. Model calculations with OSPM (Operational Street Pollution Model including its internal chemistry module are able to reproduce very well the trends in the measured annual NO2-concentrations over a 10 year period. The relevant parameters for variations between the years are the NOx-emissions, primary NO2-emissions, ozone concentrations, wind conditions, and background concentrations. A simplified chemistry model based on annual mean NOx- and NO2-concentrations, and background ozone concentrations, as well as primary NO2-emissions is presented as a better method than the updated Romberg approach. This model simulates the annual mean NO2-concentrations much more accurately than the conventional and the updated Romberg approaches.

Urban gamma spectrometry. Report 2

Energy Technology Data Exchange (ETDEWEB)

Aage, H.K. (Technical Univ. of Denmark, Kgs. Lyngby (Denmark)); Kuukankorpi, S.; Moring, M.; Smolander, P.; Toivonen, H. (Radiation and Nuclear Safety Authority, Helsinki (Finland))

2009-06-15

Urban gamma spectrometry has been given only minor attention with the focus being on rural gamma spectrometry. However, in recent years the Nordic emergency management authorities have turned focus towards border control and lost or stolen sources. Gamma spectra measured in urban areas are characterized by a wide variety of spectrum shapes and very fast changes in environmental background. In 2004 a Danish CGS (Carborne Gamma Spectrometry) survey took place in Copenhagen. It was found that gamma spectrometry in urban areas is far more complicated to interpret than had previously been thought and a new method 'Fitting with Spectral Components', FSC, based on NASVD, was tested with some success. In Finland, a database 'LINSSI' has been developed for spectral data management. In CGS search mode a 'peak hypothesis test' is applied to the measured spectra. This system was tested during the Helsinki 2005 Athletics World Championship and it provides fast and reliable automated alarms for intermediate and high level signals. In Sweden mobile detector systems are used for border controls and problems are encountered when making measurement in harbour, container areas. The methods for handling data and for interpretation of urban gamma spectrometry measurements were compared and tested on the same data sets from Copenhagen and Helsinki. Software tools were developed for converting data between the Finnish LINSSI database and the binary file formats used in Denmark and Sweden. The Processing methods used at DTU and STUK have different goals. The ASSS and FSC methods are designed to optimize the overall detection capability of the system, while sacrificing speed, usability and to a certain level robustness. These methods cannot always be used for real time analysis. The Peak Significance method is designed to give robust alarms in real time, while sacrificing some of the detection capability. Thus these methods are not interchangeable, but rather

Urban gamma spectrometry. Report 2

International Nuclear Information System (INIS)

Aage, H.K.; Kuukankorpi, S.; Moring, M.; Smolander, P.; Toivonen, H.

2009-06-01

Urban gamma spectrometry has been given only minor attention with the focus being on rural gamma spectrometry. However, in recent years the Nordic emergency management authorities have turned focus towards border control and lost or stolen sources. Gamma spectra measured in urban areas are characterized by a wide variety of spectrum shapes and very fast changes in environmental background. In 2004 a Danish CGS (Carborne Gamma Spectrometry) survey took place in Copenhagen. It was found that gamma spectrometry in urban areas is far more complicated to interpret than had previously been thought and a new method 'Fitting with Spectral Components', FSC, based on NASVD, was tested with some success. In Finland, a database 'LINSSI' has been developed for spectral data management. In CGS search mode a 'peak hypothesis test' is applied to the measured spectra. This system was tested during the Helsinki 2005 Athletics World Championship and it provides fast and reliable automated alarms for intermediate and high level signals. In Sweden mobile detector systems are used for border controls and problems are encountered when making measurement in harbour, container areas. The methods for handling data and for interpretation of urban gamma spectrometry measurements were compared and tested on the same data sets from Copenhagen and Helsinki. Software tools were developed for converting data between the Finnish LINSSI database and the binary file formats used in Denmark and Sweden. The Processing methods used at DTU and STUK have different goals. The ASSS and FSC methods are designed to optimize the overall detection capability of the system, while sacrificing speed, usability and to a certain level robustness. These methods cannot always be used for real time analysis. The Peak Significance method is designed to give robust alarms in real time, while sacrificing some of the detection capability. Thus these methods are not interchangeable, but rather complementary. An ideal system

Urbanization effect on trends in sunshine duration in China

Directory of Open Access Journals (Sweden)

Y. Wang

2017-07-01

Full Text Available There is an ongoing debate on whether the observed decadal variations in surface solar radiation, known as dimming and brightening periods, are a large-scale or solely local phenomenon. We investigated this issue using long-term sunshine duration records from China, which experienced a rapid increase in urbanization during the past decades. Over the period 1960–2013, 172 pairs of urban and nearby rural stations were analyzed. Urban and rural sunshine duration trends show similar spatial patterns during a dimming phase (1960–1989 and a subsequent period during which trends were leveling off (1990–2013. This indicates that rather than local effects, the trends in sunshine duration are on more of a national or regional scale in China. Nevertheless, in the dimming phase, the declining rate of sunshine duration in rural areas is around two-thirds of that in urban areas. The ratio of rural to urban dimming generally increases from a minimum of 0.39 to a maximum of 0.87 with increasing indices of urbanization calculated based on the year 2013. It reaches a maximum when the urbanization level exceeds 50 %, the urban population exceeds 20 million, or the population density becomes higher than 250 person km−2. After the transition into the leveling-off period, sunshine duration trends are no longer significantly affected by urbanization. Meanwhile, the number of laws and regulations related to air pollution and investment in pollution treatment have been increasing in China.

Lead contamination and transfer in urban environmental compartments analyzed by lead levels and isotopic compositions.

Science.gov (United States)

Hu, Xin; Sun, Yuanyuan; Ding, Zhuhong; Zhang, Yun; Wu, Jichun; Lian, Hongzhen; Wang, Tijian

2014-04-01

Lead levels and isotopic compositions in atmospheric particles (TSP and PM2.5), street dust and surface soil collected from Nanjing, a mega city in China, were analyzed to investigate the contamination and the transfer of lead in urban environmental compartments. The lead contents in TSP and PM2.5 are significantly higher than them in the surface soil and street dust (p lead to the major crustal elements (Al, Sr, Ti and Fe) indicates significant lead enrichment in atmospheric particles. The plots of (206)Pb/(207)Pb vs.(208)Pb/(206)Pb and (206)Pb/(207)Pb vs. 1/Pb imply that the street dust and atmospheric particles (TSP and PM2.5) have very similar lead sources. Coal emissions and smelting activities may be the important lead sources for street dust and atmospheric particles (TSP and PM2.5), while the deposition of airborne lead is an important lead source for urban surface soil. Copyright © 2013 Elsevier Ltd. All rights reserved.

Urbane Projekter

DEFF Research Database (Denmark)

Andersen, Anne Juel

2013-01-01

of Chapter 1 ’problem and research questions’, Chapter 2 ’place, discourse and planning as a theoretical framework’ and Chapter 3 ’research design’. Part 2 ’urban practice locally, nationally and globally’ consisting of Chapter 4 ’background and context, urban trans- formations in Aalborg from 1950 to 2013...... of Chapter 9 with the same name. The analysis results and thus the conclusions are at 3 levels of knowledge: Historically specific development in terms of urban planning practices respectively in Aalborg and natio- nally/internationally The tools here have been a focus on different rationales or urban...... projects as a strategic tool in urban policy, development of place perceptions, the use of narratives in the planning processes, the functions of representations as discursive devised imagined realities, power structures and planning approaches - knowledge that can be used in the future practice of other...

Total and Bioaccessible Soil Arsenic and Lead Levels and Plant Uptake in Three Urban Community Gardens in Puerto Rico

Directory of Open Access Journals (Sweden)

John Misenheimer

2018-01-01

Full Text Available Arsenic (As and lead (Pb are two contaminants of concern associated with urban gardening. In Puerto Rico, data currently is limited on As and Pb levels in urban garden soils, soil metal (loid bioaccessibility, and uptake of As and Pb in soil by edible plants grown in the region. This study examined total and bioaccessible soil As and Pb concentrations and accumulation in 10 commonly grown garden plants collected from three urban community gardens in Puerto Rico. Bioavailability values were predicted using bioaccessibility data to compare site-specific bioavailability estimates to commonly used default exposure assumptions. Total and bioaccessible As levels in study soils ranged from 2 to 55 mg/kg and 1 to 18 mg/kg, respectively. Total and bioaccessible Pb levels ranged from 19 to 172 mg/kg and 17 to 97 mg/kg, respectively. Measured bioaccessibility values corresponded to 19% to 42% bioaccessible As and 61% to 100% bioaccessible Pb when expressed as a percent of total As and Pb respectively. Predicted relative percent bioavailability of soil As and Pb based on measured bioaccessibility values ranged from 18% to 36% and 51% to 85% for As and Pb respectively. Transfer factors (TFs measuring uptake of As in plants from soil ranged from 0 to 0.073 in the edible flesh (fruit or vegetable of plant tissues analyzed and 0.073 to 0.444 in edible leaves. Pb TFs ranged from 0.002 to 0.012 in flesh and 0.023 to 0.204 in leaves. Consistent with TF values, leaves accumulated higher concentrations of As and Pb than the flesh, with the highest tissue concentrations observed in the culantro leaf (3.2 mg/kg dw of As and 8.9 mg/kg dw of Pb. Leaves showed a general but not statistically-significant (α = 0.05 trend of increased As and Pb concentration with increased soil levels, while no trend was observed for flesh tissues. These findings provide critical data that can improve accuracy and reduce uncertainty when conducting site-specific risk determination of

Histological changes in lung tissues related with sub-chronic exposure to ambient urban levels of PM2.5 in Córdoba, Argentina

Science.gov (United States)

Tavera Busso, Iván; Vera, Anahí; Mateos, Ana Carolina; Amarillo, Ana Carolina; Carreras, Hebe

2017-10-01

Concentration of fine particulate matter (PM2.5) is one of the most important environmental parameters to estimate health impacts attributable to air pollution. Despite the fact there are many studies regarding PM2.5 effects on human health, most of them were performed under conditions that do not simulate the natural particles interaction with the organism. In the present paper, we studied the effects of mammals' sub-chronic exposure to PM2.5 on the lower respiratory tract, addressing realistic exposure conditions to normal urban air. Thus, we exposed Wistar rats under controlled settings to the same normal urban air, with and without particles. Next, we analyzed chemical composition of PM2.5 and lungs samples, performed a histologic examination and run the comet assay to assess genotoxic effects. We found a strong agreement between lung tissues and PM2.5 elemental composition suggesting that metals found in lungs came from the particles inhaled. Histological analysis showed a mild to moderate infiltration, with a reduction of alveoli lumen and increment of alveolar macrophages and periodic acid-Schiff (PAS) (+) cells in treated animals. We also observed an increase in the number of nuclei with comets, mostly comets type 3, with a high DNA fragmentation as well. These results provide strong evidence that sub-chronic exposure to low particle levels, even below the 24 h WHO standard, can cause injuries in lungs tissues and DNA damage, as well.

Responses of herbaceous plants to urban air pollution: Effects on growth, phenology and leaf surface characteristics

International Nuclear Information System (INIS)

Honour, Sarah L.; Bell, J. Nigel B.; Ashenden, Trevor W.; Cape, J. Neil; Power, Sally A.

2009-01-01

Vehicle exhaust emissions are a dominant feature of urban environments and are widely believed to have detrimental effects on plants. The effects of diesel exhaust emissions on 12 herbaceous species were studied with respect to growth, flower development, leaf senescence and leaf surface wax characteristics. A diesel generator was used to produce concentrations of nitrogen oxides (NO x ) representative of urban conditions, in solardome chambers. Annual mean NO x concentrations ranged from 77 nl l -l to 98 nl l -1 , with NO:NO 2 ratios of 1.4-2.2, providing a good experimental simulation of polluted roadside environments. Pollutant exposure resulted in species-specific changes in growth and phenology, with a consistent trend for accelerated senescence and delayed flowering. Leaf surface characteristics were also affected; contact angle measurements indicated changes in surface wax structure following pollutant exposure. The study demonstrated clearly the potential for realistic levels of vehicle exhaust pollution to have direct adverse effects on urban vegetation. - Fumigation experiments demonstrate adverse effects of exhaust emissions on urban vegetation

Polycyclic aromatic hydrocarbons levels evaluation in urban area after October 23rd 1998 promulgation

International Nuclear Information System (INIS)

Galimberti, E.; Baroni, R.; Villa, V.; Sesana, G.

1999-01-01

This paper reports the result concerning the air quality evaluation in an urban centre in the hinterland of Milan., with an high population density and an intense road traffic, relatively to polycyclic aromatic hydrocarbons (PAH) concentration levels. The data, referred to the annual season, indicate that, near high traffic road, the above compounds are always present in the concentration level analytically detectable and that the concentration of benzo(a)pyrene is 2.7 ng/m 3 . The reported study is an useful instruments both for a road town planning, in order to people disease prevention, and for monitoring the evolution of PAH concentration levels in the future [it

Rural-Urban Differences in Access to Preventive Health Care Among Publicly Insured Minnesotans.

Science.gov (United States)

Loftus, John; Allen, Elizabeth M; Call, Kathleen Thiede; Everson-Rose, Susan A

2018-02-01

Reduced access to care and barriers have been shown in rural populations and in publicly insured populations. Barriers limiting health care access in publicly insured populations living in rural areas are not understood. This study investigates rural-urban differences in system-, provider-, and individual-level barriers and access to preventive care among adults and children enrolled in a public insurance program in Minnesota. This was a secondary analysis of a 2008 statewide, cross-sectional survey of publicly insured adults and children (n = 4,388) investigating barriers associated with low utilization of preventive care. Sampling was stratified with oversampling of racial/ethnic minorities. Rural enrollees were more likely to report no past year preventive care compared to urban enrollees. However, this difference was no longer statistically significant after controlling for demographic and socioeconomic factors (OR: 1.37, 95% CI: 1.00-1.88). Provider- and system-level barriers associated with low use of preventive care among rural enrollees included discrimination based on public insurance status (OR: 2.26, 95% CI: 1.34-2.38), cost of care concerns (OR: 1.72, 95% CI: 1.03-2.89) and uncertainty about care being covered by insurance (OR: 1.70, 95% CI: 1.01-2.85). These and additional provider-level barriers were also identified among urban enrollees. Discrimination, cost of care, and uncertainty about insurance coverage inhibit access in both the rural and urban samples. These barriers are worthy targets of interventions for publicly insured populations regardless of residence. Future studies should investigate additional factors associated with access disparities based on rural-urban residence. © 2017 National Rural Health Association.

Development of a concept for non-monetary assessment of urban ecosystem services at the site level.

Science.gov (United States)

Wurster, Daniel; Artmann, Martina

2014-05-01

Determining the performance of ecosystem services at the city or regional level cannot accurately take into account the fine differences between green or gray structures. The supply of regulating ecosystem services in, for instance, parks can differ as parks vary in their land cover composition. A comprehensive ecosystem service assessment approach also needs to reflect land use to consider the demands placed on ecosystem services, which are mostly neglected by current research yet important for urban planning. For instance, if a sealed surface is no longer used, it could be unsealed to improve ecosystem service supply. Because of these scientific shortcomings, this article argues for a conceptual framework for the non-monetary assessment of urban ecosystem services at the site scale. This paper introduces a standardized method for selecting representative sites and evaluating their supply of and demand on ecosystem services. The conceptual design is supplemented by examples of Salzburg, Austria.

Determination of the levels of some heavy metals in urban run-off ...

African Journals Online (AJOL)

... were determined using Atomic Absorption Spectrophotometric technique Zinc, iron and cadmium were found in very concentration in the Urban sediment from these cities whilst for most of the locations, lead was found to be below the detection level. Iron has the highest mean concentration while lead had the lowest level.

Reading and Comprehension Levels in a Sample of Urban, Low-Income Persons

Science.gov (United States)

Delgado, Cheryl; Weitzel, Marilyn

2013-01-01

Objective: Because health literacy is related to healthcare outcomes, this study looked at reading and comprehension levels in a sample of urban, low-income persons. Design: This was a descriptive exploration of reading comprehension levels, controlled for medical problems that could impact on vision and therefore ability to read. Setting: Ninety…

Modeling PM2.5 Urban Pollution Using Machine Learning and Selected Meteorological Parameters

Directory of Open Access Journals (Sweden)

Jan Kleine Deters

2017-01-01

Full Text Available Outdoor air pollution costs millions of premature deaths annually, mostly due to anthropogenic fine particulate matter (or PM2.5. Quito, the capital city of Ecuador, is no exception in exceeding the healthy levels of pollution. In addition to the impact of urbanization, motorization, and rapid population growth, particulate pollution is modulated by meteorological factors and geophysical characteristics, which complicate the implementation of the most advanced models of weather forecast. Thus, this paper proposes a machine learning approach based on six years of meteorological and pollution data analyses to predict the concentrations of PM2.5 from wind (speed and direction and precipitation levels. The results of the classification model show a high reliability in the classification of low (25 µg/m3 and low (<10 µg/m3 versus moderate (10–25 µg/m3 concentrations of PM2.5. A regression analysis suggests a better prediction of PM2.5 when the climatic conditions are getting more extreme (strong winds or high levels of precipitation. The high correlation between estimated and real data for a time series analysis during the wet season confirms this finding. The study demonstrates that the use of statistical models based on machine learning is relevant to predict PM2.5 concentrations from meteorological data.

Global distribution and evolvement of urbanization and PM2.5 (1998-2015)

Science.gov (United States)

Yang, Dongyang; Ye, Chao; Wang, Xiaomin; Lu, Debin; Xu, Jianhua; Yang, Haiqing

2018-06-01

PM2.5 concentrations increased and have been one of the major social issues along with rapid urbanization in many regions of the world in recent decades. The development of urbanization differed among regions, PM2.5 pollution also presented discrepant distribution across the world. Thus, this paper aimed to grasp the profile of global distribution of urbanization and PM2.5 and their evolutionary relationships. Based on global data for the proportion of the urban population and PM2.5 concentrations in 1998-2015, this paper investigated the spatial distribution, temporal variation, and evolutionary relationships of global urbanization and PM2.5. The results showed PM2.5 presented an increasing trend along with urbanization during the study period, but there was a variety of evolutionary relationships in different countries and regions. Most countries in East Asia, Southeast Asia, South Asia, and some African countries developed with the rapid increase in both urbanization and PM2.5. Under the impact of other socioeconomic factors, such as industry and economic growth, the development of urbanization increased PM2.5 concentrations in most Asian countries and some African countries, but decreased PM2.5 concentrations in most European and American countries. The findings of this study revealed the spatial distributions of global urbanization and PM2.5 pollution and provided an interpretation on the evolution of urbanization-PM2.5 relationships, which can contribute to urbanization policies making aimed at successful PM2.5 pollution control and abatement.

County-level poverty is equally associated with unmet health care needs in rural and urban settings.

Science.gov (United States)

Peterson, Lars E; Litaker, David G

2010-01-01

Regional poverty is associated with reduced access to health care. Whether this relationship is equally strong in both rural and urban settings or is affected by the contextual and individual-level characteristics that distinguish these areas, is unclear. Compare the association between regional poverty with self-reported unmet need, a marker of health care access, by rural/urban setting. Multilevel, cross-sectional analysis of a state-representative sample of 39,953 adults stratified by rural/urban status, linked at the county level to data describing contextual characteristics. Weighted random intercept models examined the independent association of regional poverty with unmet needs, controlling for a range of contextual and individual-level characteristics. The unadjusted association between regional poverty levels and unmet needs was similar in both rural (OR = 1.06 [95% CI, 1.04-1.08]) and urban (OR = 1.03 [1.02-1.05]) settings. Adjusting for other contextual characteristics increased the size of the association in both rural (OR = 1.11 [1.04-1.19]) and urban (OR = 1.11 [1.05-1.18]) settings. Further adjustment for individual characteristics had little additional effect in rural (OR = 1.10 [1.00-1.20]) or urban (OR = 1.11 [1.01-1.22]) settings. To better meet the health care needs of all Americans, health care systems in areas with high regional poverty should acknowledge the relationship between poverty and unmet health care needs. Investments, or other interventions, that reduce regional poverty may be useful strategies for improving health through better access to health care. © 2010 National Rural Health Association.

Development and evaluation of GRAL-C dispersion model, a hybrid Eulerian-Lagrangian approach capturing NO-NO 2-O 3 chemistry

Science.gov (United States)

Oettl, Dietmar; Uhrner, Ulrich

2011-02-01

Based on two recent publications using Lagrangian dispersion models to simulate NO-NO 2-O 3 chemistry for industrial plumes, a similar modified approach was implemented using GRAL-C ( Graz Lagrangian Model with Chemistry) and tested on two urban applications. In the hybrid dispersion model GRAL-C, the transport and turbulent diffusion of primary species such as NO and NO 2 are treated in a Lagrangian framework while those of O 3 are treated in an Eulerian framework. GRAL-C was employed on a one year street canyon simulation in Berlin and on a four-day simulation during a winter season in Graz, the second biggest city in Austria. In contrast to Middleton D.R., Jones A.R., Redington A.L., Thomson D.J., Sokhi R.S., Luhana L., Fisher B.E.A. (2008. Lagrangian modelling of plume chemistry for secondary pollutants in large industrial plumes. Atmospheric Environment 42, 415-427) and Alessandrini S., Ferrero E. (2008. A Lagrangian model with chemical reactions: application in real atmosphere. Proceedings of the 12th Int. Conf. on Harmonization within atmospheric dispersion modelling for regulatory purposes. Croatian Meteorological Journal, 43, ISSN: 1330-0083, 235-239) the treatment of ozone was modified in order to facilitate urban scale simulations encompassing dense road networks. For the street canyon application, modelled daily mean NO x/NO 2 concentrations deviated by +0.4%/-15% from observations, while the correlations for NO x and NO 2 were 0.67 and 0.76 respectively. NO 2 concentrations were underestimated in summer, but were captured well for other seasons. In Graz a fair agreement for NO x and NO 2 was obtained between observed and modelled values for NO x and NO 2. Simulated diurnal cycles of NO 2 and O 3 matched observations reasonably well, although O 3 was underestimated during the day. A possible explanation here might lie in the non-consideration of volatile organic compounds (VOCs) chemistry.

Journal of Agriculture, Forestry and the Social Sciences - Vol 5, No 2 ...

African Journals Online (AJOL)

Journal of Agriculture, Forestry and the Social Sciences - Vol 5, No 2 (2007) ... Marketing Of Bushmeat In Peri-Urban Areas Of Ibadan Metropolis Of Oyo State, ... Sport Fisheries Potentials Of Agbokim Waterfalls, Cross River State, Nigeria ...

Influence of local meteorology and NO2 conditions on ground-level ozone concentrations in the eastern part of Texas, USA.

Science.gov (United States)

Gorai, A K; Tuluri, F; Tchounwou, P B; Ambinakudige, S

2015-02-01

The influence of local climatic factors on ground-level ozone concentrations is an area of increasing interest to air quality management in regards to future climate change. This study presents an analysis on the role of temperature, wind speed, wind direction, and NO 2 level on ground-level ozone concentrations over the region of Eastern Texas, USA. Ozone concentrations at the ground level depend on the formation and dispersion processes. Formation process mainly depends on the precursor sources, whereas, the dispersion of ozone depends on meteorological factors. Study results showed that the spatial mean of ground-level ozone concentrations was highly dependent on the spatial mean of NO 2 concentrations. However, spatial distributions of NO 2 and ozone concentrations were not uniformed throughout the study period due to uneven wind speeds and wind directions. Wind speed and wind direction also played a significant role in the dispersion of ozone. Temperature profile in the area rarely had any effects on the ozone concentrations due to low spatial variations.

Spatial distribution of ground-level urban background O3 concentrations in the Metropolitan Area of Buenos Aires, Argentina

International Nuclear Information System (INIS)

Pineda Rojas, Andrea L.; Venegas, Laura E.

2013-01-01

In this work, a recently developed urban-scale atmospheric dispersion model (DAUMOD-GRS) is applied to evaluate the ground-level ozone (O 3 ) concentrations resulting from anthropogenic area sources of NO x and VOC in the Metropolitan Area of Buenos Aires (MABA). The statistical comparison of model results with observations (including new available data from seventeen sites) shows a good model performance. Estimated summer highest diurnal O 3 1-h concentrations in the MABA vary between 15 ppb in the most urbanised area and 53 ppb in the suburbs. All values are below the air quality standard. Several runs are performed to evaluate the impact of possible future emission reductions on O 3 concentrations. Under all hypothetical scenarios, the maximum diurnal O 3 1-h concentration obtained for the area is slightly reduced (up to 4%). However, maximum diurnal O 3 concentrations could increase at some less urbanised areas of MABA depending on the relative reductions of the emissions of NO x and VOC. -- Highlights: ► A recently developed air quality model reproduces well observed O 3 levels in MABA. ► Modelled summer maximum diurnal O 3 concentrations vary in the area between 15 and 53 ppb. ► All hourly values are below the air quality standard (120 ppb). ► Possible future emission reductions would have small impact on the highest level. -- The distribution of summer maximum diurnal ground-level O 3 concentrations in the Metropolitan Area of Buenos Aires is evaluated applying a recently developed simple urban air quality model

On the Climate Variability and Energy Demands for Indoor Human Comfort Levels in Tropical Urban Environment

Science.gov (United States)

Pokhrel, R.; Ortiz, L. E.; González, J. E.; Ramírez-Beltran, N. D.

2017-12-01

The main objective of this study is to identify how climate variability influences human comfort levels in tropical urban environments. San Juan Metropolitan Area (SJMA) of the island of Puerto Rico was chosen as a reference point. A new human discomfort index (HDI) based on environmental enthalpy is defined. This index is expanded to determine the energy required to maintain indoor human comfort levels and was compared to Total Electricity consumption for the Island of Puerto Rico. Regression analysis shows that both Temperature and HDI are good indictor to predict total electrical energy consumption. Results showed that over the past 35 years the average enthalpy have increased and have mostly been above thresholds for human comfort for SJMA. The weather stations data further shows a clear indication of urbanization biases ramping up the index considered. From the trend analysis local scale (weather station) data shows a decreasing rate of maximum cooling at -11.41 kW-h/years, and minimum is increasing at 10.64 kW-h/years. To compare human comfort levels under extreme heat wave events conditions, an event of 2014 in the San Juan area was identified. The analysis for this extreme heat event is complemented by data from the National Center for environmental Prediction (NCEP) at 250km spatial resolution, North American Re-Analysis (NARR) at 32 km spatial resolution, by simulations of the Weather Forecasting System (WRF) at a resolution of 2 km, and by weather station data for San Juan. WRF simulation's results showed an improvement for both temperature and relative humidity from the input NCEP data. It also shows that difference in Energy per Capita (EPC) in urban area during a heat wave event can increase to 16% over a non-urban area. Sensitivity analysis was done by modifying the urban land cover to the most common rural references of evergreen broadleaf forest and cropland to investigate the Urban Heat Island (UHI) effect on HDI. UHI is seen to be maximum during

Area-level risk factors for adverse birth outcomes: trends in urban and rural settings.

Science.gov (United States)

Kent, Shia T; McClure, Leslie A; Zaitchik, Ben F; Gohlke, Julia M

2013-06-10

Significant and persistent racial and income disparities in birth outcomes exist in the US. The analyses in this manuscript examine whether adverse birth outcome time trends and associations between area-level variables and adverse birth outcomes differ by urban-rural status. Alabama births records were merged with ZIP code-level census measures of race, poverty, and rurality. B-splines were used to determine long-term preterm birth (PTB) and low birth weight (LBW) trends by rurality. Logistic regression models were used to examine differences in the relationships between ZIP code-level percent poverty or percent African-American with either PTB or LBW. Interactions with rurality were examined. Population dense areas had higher adverse birth outcome rates compared to other regions. For LBW, the disparity between population dense and other regions increased during the 1991-2005 time period, and the magnitude of the disparity was maintained through 2010. Overall PTB and LBW rates have decreased since 2006, except within isolated rural regions. The addition of individual-level socioeconomic or race risk factors greatly attenuated these geographical disparities, but isolated rural regions maintained increased odds of adverse birth outcomes. ZIP code-level percent poverty and percent African American both had significant relationships with adverse birth outcomes. Poverty associations remained significant in the most population-dense regions when models were adjusted for individual-level risk factors. Population dense urban areas have heightened rates of adverse birth outcomes. High-poverty African American areas have higher odds of adverse birth outcomes in urban versus rural regions. These results suggest there are urban-specific social or environmental factors increasing risk for adverse birth outcomes in underserved communities. On the other hand, trends in PTBs and LBWs suggest interventions that have decreased adverse birth outcomes elsewhere may not be reaching

Urban air quality modeling with full O 3-NO x-VOC chemistry: Implications for O 3 and PM air quality in a street canyon

Science.gov (United States)

Kim, Minjoong J.; Park, Rokjin J.; Kim, Jae-Jin

2012-02-01

We examine transport and chemical transformation of reactive pollutants on an urban street using a computation fluid dynamics (CFD) model coupled with full photochemistry of reactive pollutants. An extensive comparison between simulated results and observations is conducted to evaluate the model, focusing on a field campaign occurred in Dongfeng Middle Street in Guangzhou, China. Observed CO and NO concentrations vary diurnally following traffic volumes. The model captures this observed diurnal variation and magnitudes of CO concentrations successfully. However, simulated NO concentration is three times higher than observation. This high bias is significantly reduced in the sensitivity simulation with lower NO x emissions. We find that oxidation products of O 3 photochemistry such as NO 2 and O 3 vary differently from primary pollutants, indicating important effects of photochemical reactions on their fates. The model appears to reproduce observed O 3 and NO 2 variability with time and altitude. Our analysis shows that high NO x concentrations in the urban street canyon may efficiently produce aerosol nitrate in the presence of NH 3. Simulated inorganic NO 3- aerosol concentration reaches up to 0.3 μg m -3 in July but increases an order of magnitude higher at lower temperature that favors partitioning of gas-phase HNO 3 to aerosol-phase, implying a serious concern for urban air quality in winter.

Understanding spatial differentiation in urban decline levels

NARCIS (Netherlands)

Hoekveld, J.J.

2014-01-01

The economic and demographic changes currently manifest in many Western cities—referred to as urban decline or urban shrinkage—are receiving increased attention in public and academic debates. Although the general processes driving these changes have been identified, such processes cannot explain

Multi level governance framework for sustainable urban mobility

DEFF Research Database (Denmark)

Gudmundsson, Henrik

2013-01-01

Cities constitute the backbone of European historic development and provide the basis of its economic future. The near neglect of cities in existing European policies for sustainable growth and development such as the Europe 2020 strategy is untenable. The 2011 White Paper has sought to face...... seem essential to move cities beyond business as usual. Research-wise we need to understand in more detail the political and contextual background for successes - and failures - of European cities. This could help build an effective multi level governance framework for sustainable urban mobility...

Particulate Matter and Black Carbon Concentration Levels in Ashaiman, a Semi-Urban Area of Ghana, 2008

OpenAIRE

Sam-Quarcoo Dotse; Joshua Kwame Asane; F.G. Ofosu

2012-01-01

Particulate matter and black carbon concentration levels in Ashaiman, a semi-urban area of Ghana was assessed. Using IVL PM2.5 and PM10 particle samplers, airborne particulate matter was sampled on Teflon filters for a period of three months. In addition to determination of particulate mass in the two fractions by gravimetrical method, aerosol filters were analyzed to determine Black Carbon (BC) concentration levels using the black smoke method. BC fractions in fine and coarse, together with ...

Does urban vegetation mitigate air pollution in northern conditions?

International Nuclear Information System (INIS)

Setälä, Heikki; Viippola, Viljami; Rantalainen, Anna-Lea; Pennanen, Arto; Yli-Pelkonen, Vesa

2013-01-01

It is generally accepted that urban vegetation improves air quality and thereby enhances the well-being of citizens. However, empirical evidence on the potential of urban trees to mitigate air pollution is meager, particularly in northern climates with a short growing season. We studied the ability of urban park/forest vegetation to remove air pollutants (NO 2 , anthropogenic VOCs and particle deposition) using passive samplers in two Finnish cities. Concentrations of each pollutant in August (summer; leaf-period) and March (winter, leaf-free period) were slightly but often insignificantly lower under tree canopies than in adjacent open areas, suggesting that the role of foliage in removing air pollutants is insignificant. Furthermore, vegetation-related environmental variables (canopy closure, number and size of trees, density of understorey vegetation) did not explain the variation in pollution concentrations. Our results suggest that the ability of urban vegetation to remove air pollutants is minor in northern climates. -- Highlights: ► The ability of northern urban vegetation to remove air pollutants is minor. ► Vegetation-related environmental variables had no effect on air pollution levels. ► The ability of vegetation to clean air did not differ between summer and winter. ► Dry deposition passive samplers proved applicable in urban air pollution study. -- The ability of urban vegetation to remove air pollutants seems to be minor in northern climates

The impacts of road traffic management on urban air quality

Energy Technology Data Exchange (ETDEWEB)

Oduyemi, K.O.K. [School of Construction and Environment, University of Abertay Dundee, Dundee (United Kingdom); Davidson, B. [Department of Environmental Health and Consumer Protection, Dundee City Council, Tayside House, Crichton Street, Dundee (United Kingdom)

1998-07-11

The effects of road traffic emissions on urban air quality are investigated, using long-term nitrogen dioxide (NO{sub 2}) data. The effectiveness of the several traffic management measures that have been made in Dundee city centre, UK, within the last 5 years in relation to urban air quality is discussed. The information assessed during this study indicates that the annual mean NO{sub 2} levels at all the study sites are, at present, below the current EC and WHO (long-term) air quality standards for NO{sub 2} concentration in the ambient air. Traffic restrictions appear to be effective in protecting urban air quality. The annual mean NO{sub 2} concentration at two of the study sites is currently close to 40 {mu}g/m{sup 3}, a value published in the Air Quality Regulations 1997 for the air quality objective to be achieved by the year 2005. Proactive traffic management mitigation measures are proposed for these sites and a methodology for the consideration of traffic management alternatives, based upon traffic flow modal split, is described. Some measures proposed are based upon a survey of vehicle occupancy rates, carried out at the busiest of the four study sites. The methodology and assessment procedures presented should be invaluable to assessors of traffic management and local air quality management in a small city, both at the planning and at the auditing stage

On the local and regional influence on ground-level ozone concentrations in Hong Kong

International Nuclear Information System (INIS)

So, K.L.; Wang, T.

2003-01-01

It is imperative to consider regional scale emissions and dynamic transport in managing ozone pollution in Hong Kong. - Hong Kong is a densely populated city situated in the fast developing Pearl River Delta of southern China. In this study, the recent data on ozone (O 3 ) and related air pollutants obtained at three sites in Hong Kong are analyzed to show the variations of O 3 in urban, sub-urban and rural areas and the possible regional influences. Highest monthly averaged O 3 was found at a northeastern rural site and lowest O 3 level was observed at an urban site. The levels of NO x , CO, SO 2 and PM 10 showed a different spatial pattern with the highest level in the urban site and lowest at the rural site. Analysis of chemical species ratios such as SO 2 /NO x and CO/NO x indicated that the sites were under the influences of local and regional emissions to varying extents reflecting the characteristics of emission sources surround the respective sites. Seasonal pattern of O 3 is examined. Low O 3 level was found in summer and elevated levels occurred in autumn and spring. The latter appears different from the previous result obtained in 1996 indicating a single maximum occurring in autumn. Principal component analysis was used to further elucidate the relationships of air pollutants at each site. As expected, the O 3 variation in the northeastern rural area was largely determined by regional chemical and transport processes, while the O 3 variability at the southwestern suburban and urban sites were more influenced by local emissions. Despite the large difference in O 3 levels across the sites, total potential ozone (O 3 +NO 2 ) showed little variability. Cases of high O 3 episodes were presented and elevated O 3 levels were formed under the influence of tropical cyclone bringing in conditions of intense sunlight, high temperature and light winds. Elevated O 3 levels were also found to correlate with enhanced ratio of SO 2 to NO x , suggesting influence of

Land-use regression panel models of NO2 concentrations in Seoul, Korea

Science.gov (United States)

Kim, Youngkook; Guldmann, Jean-Michel

2015-04-01

Transportation and land-use activities are major air pollution contributors. Since their shares of emissions vary across space and time, so do air pollution concentrations. Despite these variations, panel data have rarely been used in land-use regression (LUR) modeling of air pollution. In addition, the complex interactions between traffic flows, land uses, and meteorological variables, have not been satisfactorily investigated in LUR models. The purpose of this research is to develop and estimate nitrogen dioxide (NO2) panel models based on the LUR framework with data for Seoul, Korea, accounting for the impacts of these variables, and their interactions with spatial and temporal dummy variables. The panel data vary over several scales: daily (24 h), seasonally (4), and spatially (34 intra-urban measurement locations). To enhance model explanatory power, wind direction and distance decay effects are accounted for. The results show that vehicle-kilometers-traveled (VKT) and solar radiation have statistically strong positive and negative impacts on NO2 concentrations across the four seasonal models. In addition, there are significant interactions with the dummy variables, pointing to VKT and solar radiation effects on NO2 concentrations that vary with time and intra-urban location. The results also show that residential, commercial, and industrial land uses, and wind speed, temperature, and humidity, all impact NO2 concentrations. The R2 vary between 0.95 and 0.98.

Urban sustainable development from public participation in urban management

Directory of Open Access Journals (Sweden)

L. Karimifard

2016-04-01

Full Text Available Urban management in any context has a different economic, social and political structure, which is in harmony with the existing models of organization. In spite of these differences, in order to reach a sustainable urban development, several different conferences should be referred to. In the “Brundtland Commission 1987” about urban sustainable development these definitions have been given: “preservation and promotion of the quality level of city life. This consists of ecology, culture, politics, economies, and social participation. However, this development should in no case weigh on and create any problems for the future generations”. In all the definitions of urban management and urban sustainable development and in any political context citizens’ participation in decision making and insistence on social justice are mentioned. The aim of this article is a descriptive, analytic, and comparative study of different models of popular participation in different developed countries. Each of these countries has different social and political structure. However they all have the same aim which is the citizens’ empowerment. To reach the ideal urban management model it is necessary to have a clear image of the place and participation of citizens in order to create a socially, economically and politically sustainable developed society.

Dual-Level Material and Psychological Assessment of Urban Water Security in a Water-Stressed Coastal City

Directory of Open Access Journals (Sweden)

Yajing Huang

2015-04-01

Full Text Available The acceleration of urbanization and industrialization has been gradually aggravating water security issues, such as water shortages, water pollution, and flooding or drought disasters and so on. Water security issues have become a great challenge to urban sustainable development. In this context, we proposed a dual-level material and psychological assessment method to assess urban water security. Psychological security coefficients were introduced in this method to combine material security and residents’ security feelings. A typical water-stressed coastal city in China (Dalian was chosen as a case study. The water security status of Dalian from 2010 to 2012 was analysed dynamically. The results indicated that the Dalian water security statuses from 2010 to 2012 were basically secure, but solutions to improve water security status and solve water resource problems are still required. This dual-level material and psychological assessment for urban water security has improved conventional material assessment through the introduction of psychological security coefficients, which can benefit decision-making for urban water planning, management and protection.

Use of population exposure frequency distributions to simulate effects of policy interventions on NO2 exposure

Science.gov (United States)

Dimitroulopoulou, C.; Ashmore, M. R.; Terry, A. C.

2017-02-01

Health effects of air pollution on individuals depend on their personal exposure, but few modelling tools are available which can predict how the distribution of personal exposures within a city will change in response to policies to reduce emissions both indoors and outdoors. We describe a new probabilistic modelling framework (INDAIR-2/EXPAIR), which provides predictions of the personal exposure frequency distribution (PEFD) across a city to assess the effects of both reduced emissions from home sources and reduced roadside concentrations on population exposure. The model uses a national time activity database, which gives the percentage of each population group in different residential and non-residential micro-environments, and links this, for the home, to predictions of concentrations from a three-compartment model, and for non-residential microenvironments to empirical indoor/outdoor ratios. This paper presents modelled PEFDs for NO2 in the city of Leicester, for children, the elderly, and office workers, comparing results in different seasons and on different days of the week. While the mean NO2 population exposure was close to, or below the urban background concentration, the 95%ile of the PEFD was well above the urban background concentration. The relationship between both mean and 95%ile PEFD and urban background concentrations was strongly influenced by air exchange rate. The 24 h mean PEFD showed relative small differences between the population groups, with both removal of home sources and reductions of roadside concentrations on roads with a high traffic density having similar effects in reducing mean exposure. In contrast, the 1 h maximum of the PEFD was significantly higher for children and the elderly than for office workers, and showed a much greater response to reduced home emissions in these groups. The results demonstrate the importance of understanding the dynamics of NO2 exposure at a population level within different groups, if the benefits

Interactive effects of high CO2 and SO2 on growth and antioxidant levels in wheat

NARCIS (Netherlands)

Rao, M.V.; De Kok, L.J.

1994-01-01

The impact of elevated CO2 and/or SO2 on the growth and antioxidant levels of wheat {Triticum aestivum L. cv. Urban) plants has been studied. High CO2 (0.7 ml I-1) significantly enhanced shoot biomass and photosynthetic capacity, while exposure to SO2 (0.14 ul I-1) resulted in a decreased shoot

Comparison of Effect of Two-Hour Exposure to Forest and Urban Environments on Cytokine, Anti-Oxidant, and Stress Levels in Young Adults.

Science.gov (United States)

Im, Su Geun; Choi, Han; Jeon, Yo-Han; Song, Min-Kyu; Kim, Won; Woo, Jong-Min

2016-06-23

The purpose of this study was to investigate the effect of two-hour exposure to a forest environment on cytokine, anti-oxidant and stress levels among university students and to compare the results to those measured in urban environments. Forty-one subjects were recruited. For our crossover design, subjects were divided into two groups based on similar demographic characteristics. Group A remained in the urban environment and was asked to perform regular breathing for 2 h. Blood samples were collected and the serum levels of cytokines including interleukin-6 (IL-6), IL-8, tumor necrosis factor-α (TNF-α), and glutathione peroxidase (GPx) were examined. Subjects were moved to a small town in a rural area for an equal amount of time to exclude carryover effects, and then remained for another 2 h in a forest environment. The second set of blood samples was collected to assess the effect of exposure to the forest environment. Using the same method, Group B was first exposed to the forest environment, followed by exposure to the urban environment. Blood samples collected after the subjects were exposed to the forest environment showed significantly lower levels of IL-8 and TNF-α compared to those in samples collected after urban environment exposure (10.76 vs. 9.21, t = 4.559, p forest environment (LnGPx = 5.09 vs. LnGPx = 5.21, t = -2.039, p < 0.05).

Comparison of the N Reactor and Ignalina Unit No. 2 Level 1 Probabilistic Safety Assessments

International Nuclear Information System (INIS)

Coles, G.A.; McKay, S.L.

1995-06-01

A multilateral team recently completed a full-scope Level 1 Probabilistic Safety Assessment (PSA) on the Ignalina Unit No. 2 reactor plant in Lithuania. This allows comparison of results to those of the PSA for the U.S. Department of Energy's (DOE) N Reactor. The N Reactor, although unique as a Western design, has similarities to Eastern European and Soviet graphite block reactors

Vol 41 No 2

African Journals Online (AJOL)

Esem

3 Centre for Primary Care Research. Medical Journal of Zambia, Vol. 41, No. 2: 59 - 64 (2014) ... pollutants by inhaling second-hand tobacco smoke are at risk of adverse health ..... To put the measured PM levels into perspective, a. 2.5. 5.

Effectiveness of green infrastructure for improvement of air quality in urban street canyons.

Science.gov (United States)

Pugh, Thomas A M; Mackenzie, A Robert; Whyatt, J Duncan; Hewitt, C Nicholas

2012-07-17

Street-level concentrations of nitrogen dioxide (NO(2)) and particulate matter (PM) exceed public health standards in many cities, causing increased mortality and morbidity. Concentrations can be reduced by controlling emissions, increasing dispersion, or increasing deposition rates, but little attention has been paid to the latter as a pollution control method. Both NO(2) and PM are deposited onto surfaces at rates that vary according to the nature of the surface; deposition rates to vegetation are much higher than those to hard, built surfaces. Previously, city-scale studies have suggested that deposition to vegetation can make a very modest improvement (street canyons. This study shows that increasing deposition by the planting of vegetation in street canyons can reduce street-level concentrations in those canyons by as much as 40% for NO(2) and 60% for PM. Substantial street-level air quality improvements can be gained through action at the scale of a single street canyon or across city-sized areas of canyons. Moreover, vegetation will continue to offer benefits in the reduction of pollution even if the traffic source is removed from city centers. Thus, judicious use of vegetation can create an efficient urban pollutant filter, yielding rapid and sustained improvements in street-level air quality in dense urban areas.

SEA LEVEL RISE AND ITS POTENTIAL IMPACTS ON COASTAL URBAN AREA: A CASE OF ETI-OSA, NIGERIA

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Ayodele Michael AGBOOLA

2016-10-01

Full Text Available This study examines the spatial extent of coastal urban development and its potential sensitivity to sea-level rise. The main aim of the study is to critically examine the extent of growth in Eti-Osa over time, and the potential impacts of sea leve rise. Landsat Enhanced Thematic Mapper Plus (ETM+ imageries of years 2000 and 2015 were used to evaluate the different land use type identified. Post-classification change detection method was used to evaluate the output of the maximum likelihood supervised classification analysis done. This was also used to estimate the changes induces through urban development on the environment which accounts for the biodiversity loss. ASTER GDEM 2 imagery of 2011 was used to generate the elevation data used for the inundation analysis. Thus, both Land use map of Eti-Osa in 2015 and the down scaled Sea-level rise scenarios (at 0.5 to 15 meters were used for the inundation mapping. Results obtained from this research affirms that indeed EtiOsa has been subjected to gross urban expansion giving room for diverse forms of environmental degradation among which are huge replacement of natural land cover with built-up, reclamation of wetlands and sand filling of water bodies. This basically illustrates growth but also the risk that accompanies the advent of excessive alteration of natural ecosystem as Sea-level rise projections imply in this research.

HIRDLS/Aura Level 3 Nitrogen Dioxide (NO2) 1deg Lat Zonal Fourier Coefficients V007 (H3ZFCNO2) at GES DISC

Data.gov (United States)

National Aeronautics and Space Administration — The "HIRDLS/Aura Level 3 Nitrogen Dioxide (NO2) Zonal Fourier Coefficients" version 7 data product (H3ZFCNO2) contains the entire mission (~3 years) of HIRDLS data...

Production of electronically excited NO via DEA to NO2

Science.gov (United States)

Gope, Krishnendu; Tadsare, Vishvesh; Prabhudesai, Vaibhav S.; Krishnakumar, E.

2017-12-01

Dissociative electron attachment (DEA) to NO2 in the 7-11 eV range is studied using velocity slice imaging technique. Two distinct channels are observed in the DEA corresponding to O- + NO(A 2Σ+) and O- + NO(C 2Π and/or D 2Σ+). While NO(A 2Σ+) is found to be formed only in very high vibrational levels, NO(C 2Π and/or D 2Σ+) is found to be formed with vibrational distribution starting from v = 0. From the angular distribution of the O- ions leading to the NO(C 2Π and/or D 2Σ+) channel, we obtain the symmetry of the negative ion resonance to be dominantly B1 with small contribution from B2. Contribution to the Topical Issue: "Low Energy Positron and Electron Interactions", edited by James Sullivan, Ron White, Michael Bromley, Ilya Fabrikant, and David Cassidy.

Emissions of NO, NO2 and PM from inland shipping

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R. Kurtenbach

2016-11-01

Full Text Available Particulate matter (PM and nitrogen oxides NOx (NOx =  NO2+ NO are key species for urban air quality in Europe and are emitted by mobile sources. According to European recommendations, a significant fraction of road freight should be shifted to waterborne transport in the future. In order to better consider this emission change pattern in future emission inventories, in the present study inland water transport emissions of NOx, CO2 and PM were investigated under real world conditions on the river Rhine, Germany, in 2013. An average NO2 ∕ NOx emission ratio of 0.08 ± 0.02 was obtained, which is indicative of ship diesel engines without exhaust gas aftertreatment systems. For all measured motor ship types and operation conditions, overall weighted average emission indices (EIs, as emitted mass of pollutant per kg burnt fuel of EINOx =  54 ± 4 g kg−1 and a lower limit EIPM1 ≥  2.0 ± 0.3 g kg−1, were obtained. EIs for NOx and PM1 were found to be in the range of 20–161 and  ≥  0.2–8.1 g kg−1 respectively. A comparison with threshold values of national German guidelines shows that the NOx emissions of all investigated motor ship types are above the threshold values, while the obtained lower limit PM1 emissions are just under. To reduce NOx emissions to acceptable values, implementation of exhaust gas aftertreatment systems is recommended.

Impacts of urban land-surface forcing on ozone air quality in the Seoul metropolitan area

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Y.-H. Ryu

2013-02-01

Full Text Available Modified local meteorology owing to heterogeneities in the urban–rural surface can affect urban air quality. In this study, the impacts of urban land-surface forcing on ozone air quality during a high ozone (O₃ episode in the Seoul metropolitan area, South Korea, are investigated using a high-resolution chemical transport model (CMAQ. Under fair weather conditions, the temperature excess (urban heat island significantly modifies boundary layer characteristics/structures and local circulations. The modified boundary layer and local circulations result in an increase in O₃ levels in the urban area of 16 ppb in the nighttime and 13 ppb in the daytime. Enhanced turbulence in the deep urban boundary layer dilutes pollutants such as NO_x, and this contributes to the elevated O₃ levels through the reduced O₃ destruction by NO in the NO_x-rich environment. The advection of O₃ precursors over the mountains near Seoul by the prevailing valley-breeze circulation in the mid- to late morning results in the build-up of O₃ over the mountains in conjunction with biogenic volatile organic compound (BVOC emissions there. As the prevailing local circulation in the afternoon changes to urban-breeze circulation, the O₃-rich air masses over the mountains are advected over the urban area. The urban-breeze circulation exerts significant influences on not only the advection of O₃ but also the chemical production of O₃ under the circumstances in which both anthropogenic and biogenic (natural emissions play important roles in O₃ formation. As the air masses that are characterized by low NO_x and high BVOC levels and long OH chain length are advected over the urban area from the surroundings, the ozone production efficiency increases in the urban area. The relatively strong vertical mixing in the urban boundary layer embedded in the

Top-down NOX Emissions of European Cities Derived from Modelled and Spaceborne Tropospheric NO2 Columns

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Verstraeten, W. W.; Boersma, K. F.; Douros, J.; Williams, J. E.; Eskes, H.; Delcloo, A. W.

2017-12-01

High nitrogen oxides (NOX = NO + NO2) concentrations near the surface impact humans and ecosystems badly and play a key role in tropospheric chemistry. NO2 is an important precursor of tropospheric ozone (O3) which in turn affects the production of the hydroxyl radical controlling the chemical lifetime of key atmospheric pollutants and reactive greenhouse gases. Combustion from industrial, traffic and household activities in large and densely populated urban areas result in high NOX emissions. Accurate mapping of these emissions is essential but hard to do since reported emissions factors may differ from real-time emissions in order of magnitude. Modelled NO2 levels and lifetimes also have large associated uncertainties and overestimation in the chemical lifetime which may mask missing NOX chemistry in current chemistry transport models (CTM's). The simultaneously estimation of both the NO2 lifetime and as well as the concentrations by applying the Exponentially Modified Gaussian (EMG) method on tropospheric NO2 columns lines densities should improve the surface NOX emission estimates. Here we evaluate if the EMG methodology applied on the tropospheric NO2 columns simulated by the LOTOS-EUROS (Long Term Ozone Simulation-European Ozone Simulation) CTM can reproduce the NOX emissions used as model input. First we process both the modelled tropospheric NO2 columns for the period April-September 2013 for 21 selected European urban areas under windy conditions (averaged vertical wind speeds between surface and 500 m from ECMWF > 2 m s-1) as well as the accompanying OMI (Ozone Monitoring Instrument) data providing us with real-time observation-based estimates of midday NO2 columns. Then we compare the top-down derived surface NOX emissions with the 2011 MACC-III emission inventory, used in the CTM as input to simulate the NO2 columns. For cities where NOX emissions can be assumed as originating from one large source good agreement is found between the top-down derived

WHEN GROWTH IS NO LONGER THE NORM: TEACHING URBAN DESIGN IN A TIME OF TRANSFORMATION

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Sujata Shetty

2010-07-01

Full Text Available Over the past few years, there has been increasing interest in cities that are rapidly losing population, so-called shrinking cities. This is becoming a global phenomenon, with shrinking cities found on every continent. The decline has been attributed variously to changing demographics, suburbanization, postsocialist transformation and deindustrialization. We are just beginning to develop approaches to dealing with shrinkage and its consequences – vacancy, abandonment, and limited public and private resources. However, there is currently little faith in the ability of design-related disciplines to deal with shrinking cities. Some authors argue that disciplines such as architecture, urban design and urban planning have always planned for growth and have reached their limits when dealing with shrinking cities (Oswalt, 2006. Still others suggest that restructuring should be seen as an opportunity (Vey, 2007. This paper challenges the first view and responds to the second by suggesting that design education can and must respond to these new realities. It critically examines a collaborative urban design studio that was part of an attempt to transform a part of a shrinking city in the American ‘rustbelt.’ The city, once a flourishing manufacturing center, is now facing steep economic decline along with the decline of the auto industry. It is also home to a university that is beginning efforts to revitalize neighborhoods adjacent to the campus. The studio, which brought together architecture and urban planning students from two different universities to work on a section of the city including the campus area, suggests possibilities for preparing students to work in an environment where economic growth is no longer the norm. The following lessons emerged: 1 In a shrinking city, urban designers may need to focus less on designing the solids and more on meeting the challenges of the voids. 2 In spite of urban design’s historical bias towards

Indoor air quality in urban and rural kindergartens: short-term studies in Silesia, Poland.

Science.gov (United States)

Błaszczyk, Ewa; Rogula-Kozłowska, Wioletta; Klejnowski, Krzysztof; Kubiesa, Piotr; Fulara, Izabela; Mielżyńska-Švach, Danuta

2017-01-01

More than 80% of people living in urban areas who monitor air pollution are exposed to air quality levels that exceed limits defined by the World Health Organization (WHO). Although all regions of the world are affected, populations in low-income cities are the most impacted. According to average annual levels of fine particulate matter (PM2.5, ambient particles with aerodynamic diameter of 2.5 μm or less) presented in the urban air quality database issued by WHO in 2016, as many as 33 Polish cities are among the 50 most polluted cities in the European Union (EU), with Silesian cities topping the list. The aim of this study was to characterize the indoor air quality in Silesian kindergartens based on the concentrations of gaseous compounds (SO 2 , NO 2 ), PM2.5, and the sum of 15 PM2.5-bound polycyclic aromatic hydrocarbons (PAHs), including PM2.5-bound benzo(a)pyrene (BaP), as well as the mutagenic activity of PM2.5 organic extracts in Salmonella assay (strains: TA98, YG1024). The assessment of the indoor air quality was performed taking into consideration the pollution of the atmospheric air (outdoor). I/O ratios (indoor/outdoor concentration) for each investigated parameter were also calculated. Twenty-four-hour samples of PM2.5, SO 2 , and NO 2 were collected during spring in two sites in southern Poland (Silesia), representing urban and rural areas. Indoor samples were taken in naturally ventilated kindergartens. At the same time, in the vicinity of the kindergarten buildings, the collection of outdoor samples of PM2.5, SO 2 , and NO 2 was carried out. The content of BaP and the sum of 15 studied PAHs was determined in each 24-h sample of PM2.5 (indoor and outdoor). In the urban site, statistically lower concentrations of SO 2 and NO 2 were detected indoors compared to outdoors, whereas in the rural site, such a relationship was observed only for NO 2 . No statistically significant differences in the concentrations of PM2.5, PM2.5-bound BaP, and Σ15 PAHs

Aircraft observations of aerosols O{sub 3} and NO{sub y} in a nighttime urban plume

Energy Technology Data Exchange (ETDEWEB)

Berkowitz, C.M.; Zaveri, R.A.; Xindi Bian; Shiyuan Zhong; Disselkamp, R.S.; Laulainen, N.S.; Chapman, E.G. [Pacific Northwest National Lab., Richland, WA (United States)

2001-05-01

Nighttime measurements of aerosol surface area, O{sub 3}, NO{sub y} and moisture were made downwind of Portland, Oregon, as part of a study to characterize the chemistry in a nocturnal urban plume. Air parcels sampled within the urban plume soon after sunset had positive correlations between O{sub 3}, relative humidity, NO{sub y} and aerosol number density. However, the air parcels sampled within the urban plume just before dawn had O{sub 3} mixing ratios that were highly anti-correlated with aerosol number density, NO{sub y} and relative humidity. Back-trajectories from a mesoscale model show that both the post-sunset and pre-dawn parcels came from a common maritime source to the northwest of Portland. The pre-dawn parcels with strong anti-correlations passed directly over Portland in contrast to the other parcels that were found to pass west of Portland. Several gas-phase mechanisms and a heterogeneous mechanism involving the loss of O{sub 3} to the aerosol surface, are examined to explain the observed depletion in O{sub 3} within the pre-dawn parcels that had passed over Portland. (Author)

Temperature, ozone, and mortality in urban and non-urban counties in the northeastern United States.

Science.gov (United States)

Madrigano, Jaime; Jack, Darby; Anderson, G Brooke; Bell, Michelle L; Kinney, Patrick L

2015-01-07

Most health effects studies of ozone and temperature have been performed in urban areas, due to the available monitoring data. We used observed and interpolated data to examine temperature, ozone, and mortality in 91 urban and non-urban counties. Ozone measurements were extracted from the Environmental Protection Agency's Air Quality System. Meteorological data were supplied by the National Center for Atmospheric Research. Observed data were spatially interpolated to county centroids. Daily internal-cause mortality counts were obtained from the National Center for Health Statistics (1988-1999). A two-stage Bayesian hierarchical model was used to estimate each county's increase in mortality risk from temperature and ozone. We examined county-level associations according to population density and compared urban (≥1,000 persons/mile(2)) to non-urban (PI: 0.08, 0.83) in urban counties, while this same increase in ozone was associated with a 0.73% increase (95% PI: 0.19, 1.26) in non-urban counties. An increase in temperature from 70°F to 90°F (21.2°C 32.2°C) was associated with a 8.88% increase in mortality (95% PI: 7.38, 10.41) in urban counties and a 8.08% increase (95% PI: 6.16, 10.05) in non-urban counties. County characteristics, such as population density, percentage of families living in poverty, and percentage of elderly residents, partially explained the variation in county-level associations. While most prior studies of ozone and temperature have been performed in urban areas, the impacts in non-urban areas are significant, and, for ozone, potentially greater. The health risks of increasing temperature and air pollution brought on by climate change are not limited to urban areas.

Urbanization impacts on mammals across urban-forest edges and a predictive model of edge effects.

Science.gov (United States)

Villaseñor, Nélida R; Driscoll, Don A; Escobar, Martín A H; Gibbons, Philip; Lindenmayer, David B

2014-01-01

With accelerating rates of urbanization worldwide, a better understanding of ecological processes at the wildland-urban interface is critical to conserve biodiversity. We explored the effects of high and low-density housing developments on forest-dwelling mammals. Based on habitat characteristics, we expected a gradual decline in species abundance across forest-urban edges and an increased decline rate in higher contrast edges. We surveyed arboreal mammals in sites of high and low housing density along 600 m transects that spanned urban areas and areas turn on adjacent native forest. We also surveyed forest controls to test whether edge effects extended beyond our edge transects. We fitted models describing richness, total abundance and individual species abundance. Low-density housing developments provided suitable habitat for most arboreal mammals. In contrast, high-density housing developments had lower species richness, total abundance and individual species abundance, but supported the highest abundances of an urban adapter (Trichosurus vulpecula). We did not find the predicted gradual decline in species abundance. Of four species analysed, three exhibited no response to the proximity of urban boundaries, but spilled over into adjacent urban habitat to differing extents. One species (Petaurus australis) had an extended negative response to urban boundaries, suggesting that urban development has impacts beyond 300 m into adjacent forest. Our empirical work demonstrates that high-density housing developments have negative effects on both community and species level responses, except for one urban adapter. We developed a new predictive model of edge effects based on our results and the literature. To predict animal responses across edges, our framework integrates for first time: (1) habitat quality/preference, (2) species response with the proximity to the adjacent habitat, and (3) spillover extent/sensitivity to adjacent habitat boundaries. This framework will

The Contributions of Urban Landscape to Urban Life

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Ahmet Tuğrul Polat

2017-06-01

Full Text Available The issues of urban and urbanization emerged after the industrial revolution. Thus, cities that have increased rapidly in population have become points of attraction for people. Over the past century, the world population has begun to gather quickly in urban areas. Cities are transforming into unhealthy living environments with distorted ecological balance, lost green areas and aesthetic qualities. The value of accessible green spaces in urban areas is increasing to the unprecedented levels. The green space system seen as a necessity in the cities have provided the emergence of the "urban landscape" phenomenon. The issue of urban landscape is now a very serious concept. The landscape change is moving along with the level of civilization. Primarily, guidance service should be offered for more efficient, comfortable and protective areas. An interdisciplinary approach is needed in the creation of urban spaces. In this study, the term of urban landscape was explained and the researches about the contributions of urban landscape to urban life were examined and suggestions were made about the subject.

Health status in Europe: comparison of 24 urban areas to the corresponding 10 countries (EURO-URHIS 2).

Science.gov (United States)

Koster, E M; de Gelder, R; Di Nardo, F; Williams, G; Harrison, A; van Buren, L P; Lyshol, H; Patterson, L; Birt, C A; Higgerson, J; Achterberg, P W; Verma, A; van Ameijden, E J C

2017-05-01

: In Europe, over 70% of the population live in urban areas (UAs). Most international comparative health research is done using national level data, as reliable and comparable urban data are often unavailable or difficult to access. This study aims to investigate whether population health is different in UAs compared with their corresponding countries. : Routinely available health-related data were collected by the EURO-URHIS 2 project, for 10 European countries and for 24 UAs within those countries. National and UA level data for 11 health indicators were compared through the calculation of relative difference, and geographical patterns within Europe were investigated using the Mann Whitney U test. Linear regression modelling was used to adjust for population density, gross domestic product and urbanicity. : In general, the urban population in Eastern Europe is less healthy than the Western European urban population. However, people in Eastern Europe have significantly better broad health outcomes in UAs as compared with the corresponding country as a whole, whereas people in Western Europe have generally worse broader health outcomes in UAs. : For most European countries and UAs that were investigated, the national level health status data does not correspond with the health status at UA level. In order to identify health problems in UAs and to provide information for local health policy, health monitoring and international benchmarking should also be conducted at the local level. © The Author 2017. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Personal exposure to PM2,5, black smoke and NO2 in Copenhagen: relationship to bedroom and outdoor concentrations covering seasonal variation

DEFF Research Database (Denmark)

Sørensen, M.; Loft, S.; Andersen, H. V.

2005-01-01

concentrations of PM(2.5), black smoke (BS), and nitrogen dioxide (NO(2)) were measured during 2-day periods in 30 subjects (20-33 years old) living and studying in central parts of Copenhagen. The measurements were repeated in the four seasons. Information on indoor exposure sources such as environmental......Epidemiological studies have found negative associations between human health and particulate matter in urban air. In most studies outdoor monitoring of urban background has been used to assess exposure. In a field study, personal exposure as well as bedroom, front door and background...

Comparison of Effect of Two-Hour Exposure to Forest and Urban Environments on Cytokine, Anti-Oxidant, and Stress Levels in Young Adults

Directory of Open Access Journals (Sweden)

Su Geun Im

2016-06-01

Full Text Available The purpose of this study was to investigate the effect of two-hour exposure to a forest environment on cytokine, anti-oxidant and stress levels among university students and to compare the results to those measured in urban environments. Forty-one subjects were recruited. For our crossover design, subjects were divided into two groups based on similar demographic characteristics. Group A remained in the urban environment and was asked to perform regular breathing for 2 h. Blood samples were collected and the serum levels of cytokines including interleukin-6 (IL-6, IL-8, tumor necrosis factor-α (TNF-α, and glutathione peroxidase (GPx were examined. Subjects were moved to a small town in a rural area for an equal amount of time to exclude carryover effects, and then remained for another 2 h in a forest environment. The second set of blood samples was collected to assess the effect of exposure to the forest environment. Using the same method, Group B was first exposed to the forest environment, followed by exposure to the urban environment. Blood samples collected after the subjects were exposed to the forest environment showed significantly lower levels of IL-8 and TNF-α compared to those in samples collected after urban environment exposure (10.76 vs. 9.21, t = 4.559, p < 0.001, and 0.97 vs. 0.87, t = 4.130, p < 0.001. The GPx concentration increased significantly after exposure to the forest environment (LnGPx = 5.09 vs. LnGPx = 5.21, t = −2.039, p < 0.05.

Landscape urbanization and economic growth in China: positive feedbacks and sustainability dilemmas.

Science.gov (United States)

Bai, Xuemei; Chen, Jing; Shi, Peijun

2012-01-03

Accelerating urbanization has been viewed as an important instrument for economic development and reducing regional income disparity in some developing countries, including China. Recent studies (Bloom et al. 2008) indicate that demographic urbanization level has no causal effect on economic growth. However, due to the varying and changing definition of urban population, the use of demographic indicators as a sole representing indicator for urbanization might be misleading. Here, we re-examine the causal relationship between urbanization and economic growth in Chinese cities and provinces in recent decades, using built-up areas as a landscape urbanization indicator. Our analysis shows that (1) larger cities, both in terms of population size and built-up area, and richer cities tend to gain more income, have larger built-up area expansion, and attract more population, than poorer cities or smaller cities; and (2) that there is a long-term bidirectional causality between urban built-up area expansion and GDP per capita at both city and provincial level, and a short-term bidirectional causality at provincial level, revealing a positive feedback between landscape urbanization and urban and regional economic growth in China. Our results suggest that urbanization, if measured by a landscape indicator, does have causal effect on economic growth in China, both within the city and with spillover effect to the region, and that urban land expansion is not only the consequences of economic growth in cities, but also drivers of such growth. The results also suggest that under its current economic growth model, it might be difficult for China to control urban expansion without sacrificing economic growth, and China's policy to stop the loss of agricultural land, for food security, might be challenged by its policy to promote economic growth through urbanization.

Ultrasensitive ppb-level NO2 gas sensor based on WO3 hollow nanosphers doped with Fe

Science.gov (United States)

Zhang, Ziyue; haq, Mahmood; Wen, Zhen; Ye, Zhizhen; Zhu, Liping

2018-03-01

WO3 mesoporous hollow nanospheres doped with Fe synthesized by a facile method have mesoporous hollow nanospherical like morphology, small grain size (10 nm), high crystalline quality and ultrahigh surface area (165 m2/g). XRD spectra and Raman spectra indicate the Fe doping leading to the smaller cell parameters as compared to pure WO3, and the slight distortion in the crystal lattice produces a number of defects, making it a better candidate for gas sensing. XPS analysis shows that Fe-doped WO3 mesoporous hollow nanospheres have more oxygen vacancies than pure WO3, which is beneficial to the adsorption of oxygen and NO2 and its surface reaction. The gas sensor based on Fe-WO3 exhibited excellent low ppb-level (10 ppb) NO2 detecting performance and outstanding selectivity.

Calculations of color and visibility in urban atmospheres polluted by gaseous NO/sub 2/

Energy Technology Data Exchange (ETDEWEB)

Hodkinson, J.R.

1966-01-01

Calculations are made of the optical effects of persistent gaseous NO/sub 2/ pollution at 0.2-2 ppm in a city atmosphere in both the presence and absence of a polluting aerosol which does not absorb light or NO/sub 2/. It is concluded that the coloring of the horizon sky and of distant white objects would resemble whiskey, tea or cola-drinks, and the visual range would be markedly reduced. 2 references, 3 figures, 1 table.

The impact of an urban park on air pollution and noise levels in the Mediterranean city of Tel-Aviv, Israel.

Science.gov (United States)

Cohen, Pninit; Potchter, Oded; Schnell, Izhak

2014-12-01

This study examines the influence of urban parks on air quality and noise in the city of Tel-Aviv, Israel, by investigation of an urban park, an urban square and a street canyon. Simultaneous monitoring of several air pollutants and noise levels were conducted. The results showed that urban parks can reduce NOx, CO and PM10 and increase O3 concentrations and that park's mitigation effect is greater at higher NOx and PM10 levels. During extreme events, mean values of 413 ppb NOx and 80 μG/m3 PM10 were measured in the street while mean values of 89 ppb NOx and 24 μG/m3 PM10 were measured in the park. Whereas summer highest O3 values of 84 ppb were measured in the street, 94 ppb were measured in the park. The benefit of the urban park in reducing NOx and PM10 concentrations is more significant than the disadvantage of increased O3 levels. Furthermore, urban parks can reduce noise by ∼5 dB(A). Copyright © 2014 Elsevier Ltd. All rights reserved.

Dutch urban governance: multi-level of multi-scalar?

NARCIS (Netherlands)

Kokx, J.M.C.; Kempen, R. van

2010-01-01

Many accounts of urban governance emphasize municipal and neighbourhood scales, featuring local participation, social cohesion and the relationship between local government and residents. By contrast, our focus is the vertical governance processes of integrated urban policies. We concentrate on the

Large-eddy simulation of pollutant dispersion from a ground-level area source over urban street canyons with irreversible chemical reactions

Science.gov (United States)

Du, T. Z.; Liu, C.-H.; Zhao, Y. B.

2014-10-01

In this study, the dispersion of chemically reactive pollutants is calculated by large-eddy simulation (LES) in a neutrally stratified urban canopy layer (UCL) over urban areas. As a pilot attempt, idealized street canyons of unity building-height-to-street-width (aspect) ratio are used. Nitric oxide (NO) is emitted from the ground surface of the first street canyon into the domain doped with ozone (O3). In the absence of ultraviolet radiation, this irreversible chemistry produces nitrogen dioxide (NO2), developing a reactive plume over the rough urban surface. A range of timescales of turbulence and chemistry are utilized to examine the mechanism of turbulent mixing and chemical reactions in the UCL. The Damköhler number (Da) and the reaction rate (r) are analyzed along the vertical direction on the plane normal to the prevailing flow at 10 m after the source. The maximum reaction rate peaks at an elevation where Damköhler number Da is equal or close to unity. Hence, comparable timescales of turbulence and reaction could enhance the chemical reactions in the plume.

Estimation of urban surface water at subpixel level from neighborhood pixels using multispectral remote sensing image (Conference Presentation)

Science.gov (United States)

Xie, Huan; Luo, Xin; Xu, Xiong; Wang, Chen; Pan, Haiyan; Tong, Xiaohua; Liu, Shijie

2016-10-01

Water body is a fundamental element in urban ecosystems and water mapping is critical for urban and landscape planning and management. As remote sensing has increasingly been used for water mapping in rural areas, this spatially explicit approach applied in urban area is also a challenging work due to the water bodies mainly distributed in a small size and the spectral confusion widely exists between water and complex features in the urban environment. Water index is the most common method for water extraction at pixel level, and spectral mixture analysis (SMA) has been widely employed in analyzing urban environment at subpixel level recently. In this paper, we introduce an automatic subpixel water mapping method in urban areas using multispectral remote sensing data. The objectives of this research consist of: (1) developing an automatic land-water mixed pixels extraction technique by water index; (2) deriving the most representative endmembers of water and land by utilizing neighboring water pixels and adaptive iterative optimal neighboring land pixel for respectively; (3) applying a linear unmixing model for subpixel water fraction estimation. Specifically, to automatically extract land-water pixels, the locally weighted scatter plot smoothing is firstly used to the original histogram curve of WI image . And then the Ostu threshold is derived as the start point to select land-water pixels based on histogram of the WI image with the land threshold and water threshold determination through the slopes of histogram curve . Based on the previous process at pixel level, the image is divided into three parts: water pixels, land pixels, and mixed land-water pixels. Then the spectral mixture analysis (SMA) is applied to land-water mixed pixels for water fraction estimation at subpixel level. With the assumption that the endmember signature of a target pixel should be more similar to adjacent pixels due to spatial dependence, the endmember of water and land are determined

Prevalence of Diabetic Retinopathy in Urban Slums: The Aditya Jyot Diabetic Retinopathy in Urban Mumbai Slums Study-Report 2.

Science.gov (United States)

Sunita, Mohan; Singh, Arvind Kumar; Rogye, Ashwini; Sonawane, Manish; Gaonkar, Ravina; Srinivasan, Radhika; Natarajan, Sundaram; Stevens, Fred C J; Scherpbier, A J J A; Kumaramanickavel, Govindasamy; McCarty, Catherine

2017-10-01

The aims of the study were to estimate the prevalence of diabetic retinopathy (DR) and enumerate history-based risk factors in the urban slums of Western India. The population-based study was conducted in seven wards of Mumbai urban slums, where we screened 6569 subjects of ≥ 40 years age, with a response rate of 98.4%, for type 2 diabetes mellitus (T2DM) based on American Diabetes Association criteria. All subjects with T2DM underwent dilated 30° seven-field stereo-fundus-photography for DR severity grading based on modified Airlie House classification. A multivariate logistic regression model was used to assess the correlation of DR with the history-based risk factors. The prevalence of DR in the general population of Mumbai urban slums was 1.41% (95% CI 0.59-2.23) and in the T2DM population it was 15.37% (95% CI 8.87-21.87). The positive associations with DR were the longer duration of DM (≥ 11 years: OR, 12.77; 95% CI 2.93-55.61) and male gender (OR, 2.05; 95% CI 1.08-3.89); increasing severity of retinopathy was also significantly associated with longer duration of DM (p Mumbai urban slums. Duration of DM and male gender were significantly associated with DR. The slums in Western India show the trends of urban lifestyle influences similar to the rest of urban India.

Trends of NO-, NO 2-, and NH 3-emissions from gasoline-fueled Euro-3- to Euro-4-passenger cars

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Heeb, Norbert V.; Saxer, Christian J.; Forss, Anna-Maria; Brühlmann, Stefan

Vehicular emissions of reactive nitrogen compounds (RNCs) such as nitric oxide (NO), nitrogen dioxide (NO 2), and ammonia (NH 3) have a substantial impact on urban air quality. NO and NO 2 support the photochemical formation of ozone, and NH 3 is involved in the atmospheric formation of secondary aerosols. Vehicular NO is mainly formed during combustion, whereas NO 2 and NH 3 are both secondary pollutants of the catalytic converter systems. Herein we report on tail-pipe RNC emissions of gasoline-fueled Euro-3- and Euro-4-passenger cars at transient driving from 0 to 150 km h -1. Two sets of 10 in-use vehicles with comparable engine size and mileage were studied with time-resolved chemical ionization-mass spectrometry (CI-MS). Each vehicle was tested in 7 different driving cycles including the legislative European (EDC) and the US FTP-75 driving cycles. Mean emission factors (EFs) for different traffic situations are reported and effects of cold start, velocity, acceleration, and deceleration are discussed. Furthermore, critical operating conditions supporting the de novo formation of NH 3 have been identified. In the EDC, mean NO- and NH 3-EFs of 57±26 and 16±12 mg km -1 were obtained for Euro-3-vehicles; those of the Euro-4-technology were lower by about 25% and 33% at the levels of 43±46 and 10±7 mg km -1, respectively. NO 2 emissions of the investigated three-way catalyst (TWC) vehicles accounted for exhaust. Velocity and acceleration had pronounced effects on the RNC emission characteristics. Mean velocity-dependent EFs for NO and NH 3 varied by about one order of magnitude from 10 to 74 and 15 to 161 mg km -1 for Euro-3-vehicles and from 12 to 44 and 7 to 144 mg km -1 for the Euro-4 fleet. We conclude that the investigated Euro-3- and Euro-4-vehicles are mainly operated under slightly reducing conditions, where the NH 3 emissions dominate over those of the NO. Under these conditions, both vehicle fleets on an average fulfilled the valid Euro-3 and Euro-4

Application of urban neighborhoods in understanding of local level electricity consumption patterns

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Roy Chowdhury, P. K.; Bhaduri, B. L.

2017-12-01

Aggregated national or regional level electricity consumption data fail to capture the spatial variation in consumption, a function of location, climate, topography, and local economics. Spatial monitoring of electricity usage patterns helps to understand derivers of location specific consumption behavior and develop models to cater to the consumer needs, plan efficiency measures, identify settled areas lacking access, and allows for future planning through assessing requirements. Developed countries have started to deploy sensor systems such as smart meters to gather information on local level consumption patterns, but such infrastructure is virtually nonexistent in developing nations, resulting in serious dearth of reliable data for planners and policy makers. Remote sensing of artificial nighttime lights from human settlements have proven useful to study electricity consumptions from global to regional scales, however, local level studies remain scarce. Using the differences in spatial characteristics among different urban neighborhoods such as industrial, commercial and residential, observable through very high resolution day time satellite images (lights observations, which we use as a proxy for electricity consumption in the absence of ground level consumption data. The overall trends observed through this analysis provides useful explanations helping in understanding of broad electricity consumption patterns in urban areas lacking ground level observations. This study thus highlights possible application of remote sensing data driven methods in providing novel insights into local level socio-economic patterns that were hitherto undetected due to lack of ground data.

Adaptation of copper community tolerance levels after biofilm transplantation in an urban river.

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Fechner, Lise C; Versace, François; Gourlay-Francé, Catherine; Tusseau-Vuillemin, Marie-Hélène

2012-01-15

The Water Framework Directive requires the development of biological tools which can act as early-warning indicators of a sudden increase (accidental pollution) or decrease (recovery due to prevention) of the chemical status of aquatic systems. River biofilms, which respond quickly to modifications of environmental parameters and also play a key part in the functioning of aquatic ecosystems, are therefore good candidates to monitor an increase or a decrease of water pollution. In the present study, we investigated the biological response of biofilms transplanted either upstream (recovery) or downstream (deterioration of exposure levels) the urban area of Paris (France). Both modifications of Cu community tolerance levels and of global bacterial and eukaryotic community structure using automated ribosomal intergenic spacer analysis (ARISA) fingerprints were examined 15 and 30 days after the transplantation. Cu tolerance levels of the heterotrophic component of biofilms were assessed using a short-term toxicity test based on β-glucosidase (heterotrophic) activity. Cu tolerance increased for biofilms transplanted upstream to downstream Paris (5-fold increase on day 30) and conversely decreased for biofilms transplanted downstream to upstream (8-fold decrease on day 30). ARISA fingerprints revealed that bacterial and eukaryotic community structures of transplanted biofilms were closer to the structures of biofilms from the transplantation sites (or sites with similar contamination levels) than to biofilms from their sites of origin. Statistical analysis of the data confirmed that the key factor explaining biofilm Cu tolerance levels is the sampling site and not the site of origin. It also showed that Cu tolerance levels are related to the global urban contamination (both metals and nutrients). The study shows that biofilms adapt fast to modifications of their surroundings. In particular, community tolerance varies quickly and reflects the new exposure levels only 15

Urbanization and Inequality/Poverty

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Brantley Liddle

2017-11-01

Full Text Available The level of world urbanization has crossed the 50% mark, and nearly all future population growth is projected to occur in cities. Cities are disproportionately wealthy, but are associated with poverty, too. Addressing the dual challenges of urbanization and poverty is key to achieving sustainable development. This paper performs cross-sectional regressions, based on Kuznets, as a starting point for understanding the relationship between urbanization and poverty/inequality indicators. Increases in gross domestic product per capita unambiguously lowered poverty and narrowed rural-urban gaps. By contrast, levels of urbanization were either unrelated to poverty/inequality indicators and measures of rural-urban gaps, or had a nonlinear effect where, initially, increases in urbanization likewise led to improvements in those areas, while at higher levels of urbanization, increases in urbanization exacerbated poverty and rural-urban gaps.

Urbanization level and woodland size are major drivers of woodpecker species richness and abundance.

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Lukasz Myczko

Full Text Available Urbanization is a process globally responsible for loss of biodiversity and for biological homogenization. Urbanization may have a direct negative impact on species behaviour and indirect effects on species populations through alterations of their habitats, for example patch size and habitat quality. Woodpeckers are species potentially susceptible to urbanization. These birds are mostly forest specialists and the development of urban areas in former forests may be an important factor influencing their richness and abundance, but documented examples are rare. In this study we investigated how woodpeckers responded to changes in forest habitats as a consequence of urbanization, namely size and isolation of habitat patches, and other within-patch characteristics. We selected 42 woodland patches in a gradient from a semi-natural rural landscape to the city centre of Poznań (Western Poland in spring 2010. Both species richness and abundance of woodpeckers correlated positively to woodland patch area and negatively to increasing urbanization. Abundance of woodpeckers was also positively correlated with shrub cover and percentage of deciduous tree species. Furthermore, species richness and abundance of woodpeckers were highest at moderate values of canopy openness. Ordination analyses confirmed that urbanization level and woodland patch area were variables contributing most to species abundance in the woodpecker community. Similar results were obtained in presence-absence models for particular species. Thus, to sustain woodpecker species within cities it is important to keep woodland patches large, multi-layered and rich in deciduous tree species.

Urbanization level and woodland size are major drivers of woodpecker species richness and abundance.

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Myczko, Lukasz; Rosin, Zuzanna M; Skórka, Piotr; Tryjanowski, Piotr

2014-01-01

Urbanization is a process globally responsible for loss of biodiversity and for biological homogenization. Urbanization may have a direct negative impact on species behaviour and indirect effects on species populations through alterations of their habitats, for example patch size and habitat quality. Woodpeckers are species potentially susceptible to urbanization. These birds are mostly forest specialists and the development of urban areas in former forests may be an important factor influencing their richness and abundance, but documented examples are rare. In this study we investigated how woodpeckers responded to changes in forest habitats as a consequence of urbanization, namely size and isolation of habitat patches, and other within-patch characteristics. We selected 42 woodland patches in a gradient from a semi-natural rural landscape to the city centre of Poznań (Western Poland) in spring 2010. Both species richness and abundance of woodpeckers correlated positively to woodland patch area and negatively to increasing urbanization. Abundance of woodpeckers was also positively correlated with shrub cover and percentage of deciduous tree species. Furthermore, species richness and abundance of woodpeckers were highest at moderate values of canopy openness. Ordination analyses confirmed that urbanization level and woodland patch area were variables contributing most to species abundance in the woodpecker community. Similar results were obtained in presence-absence models for particular species. Thus, to sustain woodpecker species within cities it is important to keep woodland patches large, multi-layered and rich in deciduous tree species.

[The use of census data to estimate levels of urbanization].

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Darwin, M; Tukiran

1991-01-01

Problems concerning changes in the definition of urbanization for demographic analysis are examined. "This article attempts to examine the problem by clarifying the definition of the concept and indicators of urban and urbanization and by making a longitudinal analysis of urbanization using the Indonesian 1920-1990 Census data." (SUMMARY IN ENG) excerpt

Impact of the global economic crisis on metal levels in particulate matter (PM) at an urban area in the Cantabria Region (Northern Spain)

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Arruti, A.; Fernandez-Olmo, I.; Irabien, A.

2011-01-01

Air pollution by particulate matter is well linked with anthropogenic activities; the global economic crisis that broke out in the last year may be a proper indicator of this close relationship. Some economic indicators show the regional effects of the crisis on the Cantabria Region. The present work aims to evaluate the impact of the economic crisis on PM10 levels and composition at the major city of the region, Santander. Some metals linked to anthropogenic activities were measured at Santander and studied by Positive Matrix Factorization; this statistical analysis allowed to identify three main factors: urban background, industrial and molybdenum-related factor. The main results show that the temporal trend of the levels of the industrial tracers found in the present study are well agree with the evolution of the studied economic indicators; nevertheless, the urban background tracers and PM10 concentration levels are not well correlated with the studied economic indicators. - Highlights: → The impact of the crisis is higher on the PM-bound metal levels than on the PM levels. → The crisis effects on the trace metal associated to the urban background are negligible. → The temporal trend of the industrial trace metals levels and the studied economic indicators is similar. → The crisis effects on the main industrial tracer levels in PM2.5 and PM10 are similar. - The study presents an evaluation of the economic crisis impact on PM levels and composition at a coastal urban area in the Region of Cantabria (Northern Spain).

CO and NO2 pollution in a long two-way traffic road tunnel: investigation of NO2/NOx ratio and modelling of NO2 concentration.

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Indrehus, O; Vassbotn, P

2001-02-01

The CO, NO and NO2 concentrations, visibility and air flow velocity were measured using continuous analysers in a long Norwegian road tunnel (7.5 km) with traffic in both directions in April 1994 and 1995. The traffic density was monitored at the same time. The NO2 concentration exceeded Norwegian air quality limits for road tunnels 17% of the time in 1994. The traffic through the tunnel decreased from 1994 to 1995, and the mean NO2 concentration was reduced from 0.73 to 0.22 ppm. The ventilation fan control, based on the CO concentration only, was unsatisfactory and the air flow was sometimes low for hours. Models for NO2 concentration based on CO concentration and absolute air flow velocity were developed and tested. The NO2/NOx ratio showed an increase for NOx levels above 2 ppm; a likely explanation for this phenomenon is NO oxidation by O2. Exposure to high NO2 concentrations may represent a health risk for people with respiratory and cardiac diseases. In long road tunnels with two-way traffic, this study indicates that ventilation fan control based on CO concentration should be adjusted for changes in vehicle CO emission and should be supplemented by air flow monitoring to limit the NO2 concentration.

URBAN MORPHOLOGY AND AIR QUALITY IN DENSE RESIDENTIAL ENVIRONMENTS: CORRELATIONS BETWEEN MORPHOLOGICAL PARAMETERS AND AIR POLLUTION AT STREET-LEVEL

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PRIYANTHA EDUSSURIYA

2014-02-01

Full Text Available This study is the second part of the series that identifies whether site-specific urban morphological parameters are correlated with air quality. This study aims to identify the most important urban morphological parameters that affects air quality at street level that affect air quality in metropolis like Hong Kong through field measurements and statistical analyses. The study considers 20 urban residential areas in five major districts of Hong Kong and real-time street level air pollutant and microclimatic data are collected from these areas. 21 morphological variables are identified and calculated based on the geometry of the urban fabric. Using principal component analyses, it is shown that out of the many urban morphological factors, only five morphological variables (plan area density, occlusivity, aerodynamic roughness height, mean built volume, compactness factor and four land development factors (aspect ratio, distance between building, mean building height and standard deviation of building height correlate with particulate matter. Besides mineralisation factor, contiguity and canyon ratio marginally correlate with particulate matter. On the other hand, nine variables (plan area density, compactness factor, occlusivity, aerodynamic roughness height, average size of building volume, aspect ratio, distance between buildings, mean building height and standard deviations of building heights correlate with NOx. All others play insignificant roles in street-level pollution effect. Moreover statistical analyses show little correlation between CO and ozone with urban morphological parameters. It is also established that the key microclimatic variables that connects PM and NOx with the urban morphological factors are northerly wind, relative humidity and temperature, which in turn translates to affecting the street-level air pollution.

The positive pharmacy care law: an area-level analysis of the relationship between community pharmacy distribution, urbanity and social deprivation in England.

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Todd, Adam; Copeland, Alison; Husband, Andy; Kasim, Adetayo; Bambra, Clare

2014-08-12

To: (1) determine the percentage of the population in England that have access to a community pharmacy within 20 min walk; (2) explore any relationship between the walking distance and urbanity; (3) explore any relationship between the walking distance and social deprivation; and (4) explore any interactions between urbanity, social deprivation and community pharmacy access. This area level analysis spatial study used postcodes for all community pharmacies in England. Each postcode was assigned to a population lookup table and lower super output area (LSOA). The LSOA was then matched to urbanity (urban, town and fringe or village, hamlet and isolated dwellings) and deprivation decile (using the Index of Multiple Deprivation score). Access to a community pharmacy within 20 min walk. Overall, 89.2% of the population is estimated to have access to a community pharmacy within 20 min walk. For urban areas, that is 98.3% of the population, for town and fringe, 79.9% of the population, while for rural areas, 18.9% of the population. For areas of lowest deprivation (deprivation decile 1) 90.2% of the population have access to a community pharmacy within 20 min walk, compared to 99.8% in areas of highest deprivation (deprivation decile 10), a percentage difference of 9.6% (8.2, 10.9). Our study shows that the majority of the population can access a community pharmacy within 20 min walk and crucially, access is greater in areas of highest deprivation--a positive pharmacy care law. More research is needed to explore the perceptions and experiences of people--from various levels of deprivation--around the accessibility of community pharmacy services. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Personal exposures to NO2 in the EXPOLIS-study: relation to residential indoor, outdoor and workplace concentrations in Basel, Helsinki and Prague

International Nuclear Information System (INIS)

Kousa, A.; Rotko, T.; Alm, S.; Monn, C.

2001-01-01

Personal exposures, residential indoor, outdoor and workplace levels of nitrogen dioxide (NO 2 ) were measured for 262 urban adult (25-55 years) participants in three EXPOLIS centres (Basel, Switzerland; Helsinki, Finland; and Prague, Czech Republic) using passive samplers for 48-h sampling periods during 1996-1997. The average residential outdoor and indoor NO 2 levels were lowest in Helsinki (24 ± 12 and 18 ± 11 μgm -3 , respectively), highest in Prague (61 ± 20 and 43 ± 23μgm -3 ), with Basel in between (36 ± 13 and 27± 13μgm -3 ). Average workplace NO 2 levels, however, were highest in Basel (36 ± 24μgm -3 ), lowest in Helsinki (27 ± 15μgm -3 ), with Prague in between (30 ± 18μgm -3 ). A time-weighted microenvironmental exposure model explained 74% of the personal exposure variation in all centre and in average 88% of the exposures. Log-linear regression models, using residential outdoor measurements (fixed site monitoring) combined with residential and work characteristics (i.e. work location, using gas appliances and keeping windows open), explained 48% (37%) of the personal NO 2 exposure variation. Regression models based on ambient fixed site concentrations alone explained only 11-19% of personal NO 2 exposure variation. Thus, ambient fixed site monitoring alone was a poor predictor for personal NO 2 exposure variation, but adding personal questionnaire information can significantly improve the predicting power. (Author)

Morbidity at elementary school entry differs by sex and level of residence urbanization: a comparative cross-sectional study

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Lin Kuan-Chia

2007-12-01

Full Text Available Abstract Background Health is vital to a child's learning in school and success in life. Therefore, early physical examination, and follow-up if necessary, would bring parents' attention to their child's health and would likely improve outcomes. The purposes of this study are twofold: to assess the health status of first-graders and to examine the health status differences between sexes, levels of residence urbanization, and quantity of available medical resources. Methods This is a comparative descriptive study. Data from the 2002 Student Entry Physical Examination (SEPE and Student Medical History Inventory (SMHI were obtained from 203 public and private elementary schools in northern Taiwan where a population of 53,053 students was included. Frequencies, independent sample t test, one-way ANOVA along with Scheff's post hoc test, and Pearson's correlation were conducted using SPSS. Results This study showed that 13.7% of students had at least one diagnosed disease from the SMHI reported by parents. Moreover, the SEPE indicated that 79.5% students had at least one health concern. Dental caries, myopia, and obesity were the most prevalent health problems among the first-graders (69.6%, 27.1%, and 9.5%, respectively. Research results show that there were significant differences in the prevalence of dental caries, myopia, and obesity between different sexes and among levels of urbanization. However, the quantity of available medical resources made no significant difference. Conclusion Elementary school entry physical examination is an important way to detect students' health problems. It is suggested that school health interventions consider students' health profiles along with their sex and level of urbanization in planning. More research is needed to find the risk factors of the health problems. Additionally, the creation of a school health committee is suggested to implement and evaluate the entry health examination program.

Multi-scale dynamic modeling of atmospheric pollution in urban environment

International Nuclear Information System (INIS)

Thouron, Laetitia

2017-01-01

Urban air pollution has been identified as an important cause of health impacts, including premature deaths. In particular, ambient concentrations of gaseous pollutants such as nitrogen dioxide (NO 2 ) and particulate matter (PM10 and PM2.5) are regulated, which means that emission reduction strategies must be put in place to reduce these concentrations in places where the corresponding regulations are not respected. Besides, air pollution can contribute to the contamination of other media, for example through the contribution of atmospheric deposition to runoff contamination. The multifactorial and multi-scale aspects of urban make the pollution sources difficult to identify. Indeed, the urban environment is a heterogeneous space characterized by complex architectural structures (old buildings alongside a more modern building, residential, commercial, industrial zones, roads, etc.), non-uniform atmospheric pollutant emissions and therefore the population exposure to pollution is variable in space and time. The modeling of urban air pollution aims to understand the origin of pollutants, their spatial extent and their concentration/deposition levels. Some pollutants have long residence times and can stay several weeks in the atmosphere (PM2.5) and therefore be transported over long distances, while others are more local (NO x in the vicinity of traffic). The spatial distribution of a pollutant will therefore depend on several factors, and in particular on the surfaces encountered. Air quality depends strongly on weather, buildings (canyon-street) and emissions. The aim of this thesis is to address some of these aspects by modeling: (1) urban background pollution with a transport-chemical model (Polyphemus / POLAIR3D), which makes it possible to estimate atmospheric pollutants by type of urban surfaces (roofs, walls and roadways), (2) street-level pollution by explicitly integrating the effects of the building in a three-dimensional way with a multi-scale model of

Role of urbanization and air pollution in adolescent asthma: a mass screening in Taiwan.

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Lin, R S; Sung, F C; Huang, S L; Gou, Y L; Ko, Y C; Gou, H W; Shaw, C K

2001-10-01

The prevalence of asthma in school children in Taiwan is increasing. This study used mass screening among middle school children in Taiwan to determine the prevalence of asthma and related factors. Data were collected from parents using a self-reported questionnaire and from children using the International Study of Asthma and Allergies in Childhood (ISAAC) video questionnaire. Six study teams conducted the survey nationwide in 1995-1996, with the assistance of middle school nurses and teachers. Among the 1,018,031 students at 795 middle schools who returned questionnaires, 8.5% had a history of asthma (ranging in prevalence from 4.2% to 13% in 25 areas). The prevalence of asthma was higher in boys than in girls (10.0% vs 7%) and was highest in more urbanized areas (11.2%), followed by moderately urbanized areas (7.4%) and less urbanized and rural areas (6.5%). Controlling for age, family smoking, family incense burning, and parental education level, multivariate logistic regression models indicated that children living in an area with heavy air pollution were more likely to have asthma than those in an area with no or light pollution (odds ratio, OR = 2.01 and 95% confidence interval, CI = 1.94-2.09 based on parental ranking of pollution level, or OR = 1.30 and 95% CI = 1.18-1.42 based on pollution level reported by the Environmental Protection Administration). Adolescent asthma in Taiwan is most prevalent in the most urbanized areas and decreases in prevalence in less urbanized areas. This study also found that higher parental education level and higher area air pollution were associated with higher adolescent asthma prevalence.

Committee opinion no. 515: Health care for urban American Indian and Alaska Native women.

Science.gov (United States)

2012-01-01

Sixty percent of American Indian and Alaska Native women live in metropolitan areas. Most are not eligible for health care provided by the federal Indian Health Service (IHS). The IHS partly funds 34 Urban Indian Health Organizations, which vary in size and services. Some are small informational and referral sites that are limited even in the scope of outpatient services provided. Compared with other urban populations, urban American Indian and Alaska Native women have higher rates of teenaged pregnancy, late or no prenatal care, and alcohol and tobacco use in pregnancy. Their infants have higher rates of preterm birth, mortality, and sudden infant death syndrome than infants in the general population. Barriers to care experienced by American Indian and Alaska Native women should be addressed. The American College of Obstetricians and Gynecologists encourages Fellows to be aware of the risk profile of their urban American Indian and Alaska Native patients and understand that they often are not eligible for IHS coverage and may need assistance in gaining access to other forms of coverage. The American College of Obstetricians and Gynecologists also recommends that Fellows encourage their federal legislators to support adequate funding for the Indian Health Care Improvement Act, permanently authorized as part of the Patient Protection and Affordable Care Act.

Suicide Trends Among and Within Urbanization Levels by Sex, Race/Ethnicity, Age Group, and Mechanism of Death - United States, 2001-2015.

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Ivey-Stephenson, Asha Z; Crosby, Alex E; Jack, Shane P D; Haileyesus, Tadesse; Kresnow-Sedacca, Marcie-Jo

2017-10-06

Suicide is a public health problem and one of the top 10 leading causes of death in the United States. Substantial geographic variations in suicide rates exist, with suicides in rural areas occurring at much higher rates than those occurring in more urban areas. Understanding demographic trends and mechanisms of death among and within urbanization levels is important to developing and targeting future prevention efforts. 2001-2015. Mortality data from the National Vital Statistics System (NVSS) include demographic, geographic, and cause of death information derived from death certificates filed in the 50 states and the District of Columbia. NVSS was used to identify suicide deaths, defined by International Classification of Diseases, 10th Revision (ICD-10) underlying cause of death codes X60-X84, Y87.0, and U03. This report examines annual county level trends in suicide rates during 2001-2015 among and within urbanization levels by select demographics and mechanisms of death. Counties were collapsed into three urbanization levels using the 2006 National Center for Health Statistics classification scheme. Suicide rates increased across the three urbanization levels, with higher rates in nonmetropolitan/rural counties than in medium/small or large metropolitan counties. Each urbanization level experienced substantial annual rate changes at different times during the study period. Across urbanization levels, suicide rates were consistently highest for men and non-Hispanic American Indian/Alaska Natives compared with rates for women and other racial/ethnic groups; however, rates were highest for non-Hispanic whites in more metropolitan counties. Trends indicate that suicide rates for non-Hispanic blacks were lowest in nonmetropolitan/rural counties and highest in more urban counties. Increases in suicide rates occurred for all age groups across urbanization levels, with the highest rates for persons aged 35-64 years. For mechanism of death, greater increases in rates

Gaseous pollutants on rural and urban nursery schools in Northern Portugal.

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Nunes, R A O; Branco, P T B S; Alvim-Ferraz, M C M; Martins, F G; Sousa, S I V

2016-01-01

Indoor air quality in nursery schools is different from other schools and this has been largely ignored, particularly in rural areas. Urban and rural nursery schools have different environmental characteristics whose knowledge needs improvement. Thus, this study aimed to evaluate continuously the concentrations of CO2, CO, NO2, O3, CH2O and total VOC in three rural nursery schools and one urban, being the only one comparing urban and rural nurseries with continuous measurements, thus considering occupation and non-occupation periods. Regarding CO2, urban nursery recorded higher concentrations (739-2328 mg m(-3)) than rural nurseries (653-1078 mg m(-3)). The influence of outdoor air was the main source of CO, NO2 and O3 indoor concentrations. CO and NO2 concentrations were higher in the urban nursery and O3 concentrations were higher in rural ones. CH2O and TVOC concentrations seemed to be related to internal sources, such as furniture and flooring finishing and cleaning products. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Effect of Economic Growth, Urbanization, and Industrialization on Fine Particulate Matter (PM2.5) Concentrations in China.

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Li, Guangdong; Fang, Chuanglin; Wang, Shaojian; Sun, Siao

2016-11-01

Rapid economic growth, industrialization, and urbanization in China have led to extremely severe air pollution that causes increasing negative effects on human health, visibility, and climate change. However, the influence mechanisms of these anthropogenic factors on fine particulate matter (PM 2.5 ) concentrations are poorly understood. In this study, we combined panel data and econometric methods to investigate the main anthropogenic factors that contribute to increasing PM 2.5 concentrations in China at the prefecture level from 1999 to 2011. The results showed that PM 2.5 concentrations and three anthropogenic factors were cointegrated. The panel Fully Modified Least Squares and panel Granger causality test results indicated that economic growth, industrialization, and urbanization increased PM 2.5 concentrations in the long run. The results implied that if China persists in its current development pattern, economic growth, industrialization and urbanization will inevitably lead to increased PM 2.5 emissions in the long term. Industrialization was the principal factor that affected PM 2.5 concentrations for the total panel, the industry-oriented panel and the service-oriented panel. PM 2.5 concentrations can be reduced at the cost of short-term economic growth and industrialization. However, reducing the urbanization level is not an efficient way to decrease PM 2.5 pollutions in the short term. The findings also suggest that a rapid reduction of PM 2.5 concentrations relying solely on adjusting these anthropogenic factors is difficult in a short-term for the heavily PM 2.5 -polluted panel. Moreover, the Chinese government will have to seek much broader policies that favor a decoupling of these coupling relationships.

Level and intensity of objectively assessed physical activity among pregnant women from urban Ethiopia

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Hjorth Mads F

2012-12-01

Full Text Available Abstract Background Women in low-income countries are generally considered to have a high physical workload which is sustained during pregnancy. Although most previous studies have been based on questionnaires a recent meta-analysis of doubly labeled water data has raised questions about the actual amount of physical activity performed. In this study we report objectively assessed levels of physical activity, cardiorespiratory fitness and muscular fitness among pregnant urban Ethiopian women, and their association with demographic characteristics and anthropometric measures. Methods Physical activity was measured for seven consecutive days in 304 women using a combined uniaxial accelerometer and heart rate sensor. Activity energy expenditure was determined using a group calibration in a branched equation model framework. Type and duration of activities were reported using a 24-hour physical activity recall and grip strength was assessed using a dynamometer. Results Median (interquartile-range, IQR activity energy expenditure was 31.1 (23.7-42.0 kJ/kg/day corresponding to a median (IQR physical activity level of 1.46 (1.39-1.58. Median (IQR time in sedentary, light, and moderate-to-vigorous intensity was 1100 (999–1175, 303 (223–374 and 40 (22–69 min/day, respectively. Mean (standard deviation sleeping heart rate was 73.6 (8.0 beats/min and grip strength was 21.6 (4.5 kg. Activity energy expenditure was 14% higher for every 10 cm2 difference in arm muscle area and 10% lower for every 10 cm2 difference in arm fat area and 10-week difference in gestational age. Conclusion The level and intensity of physical activity among pregnant women from urban Ethiopia is low compared to non-pregnant women from other low income countries as well as pregnant European women from high-income countries.

Urbanization impacts on mammals across urban-forest edges and a predictive model of edge effects.

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Nélida R Villaseñor

Full Text Available With accelerating rates of urbanization worldwide, a better understanding of ecological processes at the wildland-urban interface is critical to conserve biodiversity. We explored the effects of high and low-density housing developments on forest-dwelling mammals. Based on habitat characteristics, we expected a gradual decline in species abundance across forest-urban edges and an increased decline rate in higher contrast edges. We surveyed arboreal mammals in sites of high and low housing density along 600 m transects that spanned urban areas and areas turn on adjacent native forest. We also surveyed forest controls to test whether edge effects extended beyond our edge transects. We fitted models describing richness, total abundance and individual species abundance. Low-density housing developments provided suitable habitat for most arboreal mammals. In contrast, high-density housing developments had lower species richness, total abundance and individual species abundance, but supported the highest abundances of an urban adapter (Trichosurus vulpecula. We did not find the predicted gradual decline in species abundance. Of four species analysed, three exhibited no response to the proximity of urban boundaries, but spilled over into adjacent urban habitat to differing extents. One species (Petaurus australis had an extended negative response to urban boundaries, suggesting that urban development has impacts beyond 300 m into adjacent forest. Our empirical work demonstrates that high-density housing developments have negative effects on both community and species level responses, except for one urban adapter. We developed a new predictive model of edge effects based on our results and the literature. To predict animal responses across edges, our framework integrates for first time: (1 habitat quality/preference, (2 species response with the proximity to the adjacent habitat, and (3 spillover extent/sensitivity to adjacent habitat boundaries. This

Gunshot wounds to the face: level I urban trauma center: a 10-year level I urban trauma center experience.

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Pereira, Clifford; Boyd, J Brian; Dickenson, Brian; Putnam, Brant

2012-04-01

Gunshot wounds (GSWs) to the face are an infrequent occurrence outside of a war zone. However, when they occur, they constitute a significant reconstructive challenge. We present our 10-year experience at an urban level I trauma center to define the patterns of injury, assess the morbidity and mortality, and estimate the cost to the health care system. A retrospective review was performed on all patients admitted to Harbor-UCLA Medical Center with GSWs to the head and neck region between January 1997 and January 2007. Those who had sustained GSWs to the face requiring operative intervention were closely reviewed. Between 1997 and 2007, a total of 702 patients were admitted to the Harbor UCLA Emergency Department having sustained GSWs to the head and neck region, of which 501 patients survived. Of the survivors, 28 patients (26 male, 2 female) sustained GSWs to their face requiring operative intervention. The mean age of these patients was 28 (±8.3) years. They generally presented within a few hours of the injury, but 1 individual arrived over 24 hours later. Low-velocity single gunshots (from handguns) were predominantly involved, with facial fractures occurring in all cases. Fractures were of a localized shattering type without the major displacement of bony complexes seen in motor vehicle accidents. Most required wound debridement and fracture fixation. A few patients (14.2%) underwent free tissue transfer for reconstruction (3 fibular flaps, 1 TRAM). Tracheostomy was performed in 35.7% of patients. Mean length of hospital stay was 8.3 (±7.1) days, with 50% of cases requiring admission to the intensive care unit. Mean length of intensive care unit stay was 5.2 (±5.7) days. The average cost per patient exceeded $100,000.

When Vacant Lots Become Urban Gardens: Characterizing the Perceived and Actual Food Safety Concerns of Urban Agriculture in Ohio.

Science.gov (United States)

Kaiser, Michelle L; Williams, Michele L; Basta, Nicholas; Hand, Michelle; Huber, Sarah

2015-11-01

This study was intended to characterize the perceived risks of urban agriculture by residents of four low-income neighborhoods in which the potential exists for further urban agriculture development and to provide data to support whether any chemical hazards and foodborne pathogens as potential food safety hazards were present. Sixty-seven residents participated in focus groups related to environmental health, food security, and urban gardening. In addition, soils from six locations were tested. Residents expressed interest in the development of urban gardens to improve access to healthy, fresh produce, but they had concerns about soil quality. Soils were contaminated with lead (Pb), zinc, cadmium (Cd), and copper, but not arsenic or chromium. Results from our study suggest paint was the main source of soil contamination. Detectable polyaromatic hydrocarbon (PAH) levels in urban soils were well below levels of concern. These urban soils will require further management to reduce Pb and possibly Cd bioavailability to decrease the potential for uptake into food crops. Although the number of locations in this study is limited, results suggest lower levels of soil contaminants at well-established gardens. Soil tillage associated with long-term gardening could have diluted the soil metal contaminants by mixing the contaminants with clean soil. Also, lower PAH levels in long-term gardening could be due to enhanced microbial activity and PAH degradation, dilution, or both due to mixing, similar to metals. No foodborne pathogen targets were detected by PCR from any of the soils. Residents expressed the need for clearness regarding soil quality and gardening practices in their neighborhoods to consume food grown in these urban areas. Results from this study suggest long-term gardening has the potential to reduce soil contaminants and their potential threat to food quality and human health and to improve access to fresh produce in low-income urban communities.

The rate coefficient for the reaction NO2 + NO3 yielding NO + NO2 + O2 from 273 to 313 K

Science.gov (United States)

Cantrell, Chris A.; Shetter, Richard E.; Mcdaniel, Anthony H.; Calvert, Jack G.

1990-01-01

The ratio of rate constants for the reaction NO3 + NO yielding 2 NO2 (k3) and the reaction NO2 + NO3 yielding NO + NO2 + O2 (k4) were determined by measuring of NO and NO2 concentrations of NO and NO2 in an N2O5/NO2/N2 mixture over the temperature range 273-313 K. The measured ratio was found to be expressed by the equation k3/k4 = 387 exp(-1375/T). The results are consistent with those of Hammer et al. (1986).

Spatial and Temporal Evolution of Urban Systems in China during Rapid Urbanization

Directory of Open Access Journals (Sweden)

Huan Li

2016-07-01

Full Text Available The structure of urban hierarchy and the role of cities of different sizes have drawn considerable scholarly interests and societal concerns. This paper analyzes the evolution and underlying mechanisms of urban hierarchy in China during the recent period of rapid urbanization. By comparing scale changes of seven types of cities (megacity, large city, Type I big city, Type II big city, medium-sized city, type I small city and type II small city, we find that allometry is the main characteristic of urban hierarchical evolution in China. We also test the validity of Zipf’s law and Gibrat’s law, which broaden the scope of existing studies by including county-level cities. We find that urban hierarchical distribution is lognormal, rather than Pareto. The result also shows that city size growth rates are constant across cities of different types. For better understanding of the mechanisms of urban hierarchical formation, we measure the optimal city size and resource allocation by the Pareto optimality criterion and non-parametric frontier method. The main findings are as follows: (1 scale efficiency is still at a relatively low level among the seven types of cities; (2 the economic efficiency of megacities and large cities is overestimated when compared to economic-environmental efficiency. Hence, this paper has two policy implications: (1 to correct factor market (land, labor and infrastructure investment distortions among different types of cities for the improvement of efficiency; (2 to strengthen rural property rights to improve social equity, as well as land use intensity.

Urban energy planning in Tartu

DEFF Research Database (Denmark)

Große, Juliane; Groth, Niels Boje; Fertner, Christian

The Estonian planning system allots the main responsibilities for planning activities to the local level, whereas the regional level (county) is rather weak. That implies a gap of cooperation on the regional level, leading to dispersed urban development in suburban municipalities and ongoing urban...... sprawl in the vicinity of Tartu. This development appears contrary to the concept of “low-density urbanised space” as formulated in the National Spatial Plan “Estonia 2030+” (NSP) as the central spatial development concept for Estonia and also to a compact and intensive city development as formulated...... in the Master Plan of Tartu. Since Tartu has no relevant big industries, the main employers are the municipality and the university, energy related challenges occur from transport and residential (district) heating. The modal split shows big differences between journeys within Tartu and journeys between Tartu...

NO accumulation alleviates H2 O2 -dependent oxidative damage induced by Ca(NO3 )2 stress in the leaves of pumpkin-grafted cucumber seedlings.

Science.gov (United States)

Li, Lin; Shu, Sheng; Xu, Qing; An, Ya-Hong; Sun, Jin; Guo, Shi-Rong

2017-05-01

Nitric oxide (NO) and hydrogen peroxide (H 2 O 2 ), two important signaling molecules, are stimulated in plants by abiotic stresses. In this study, we investigated the role of NO and its interplay with H 2 O 2 in the response of self-grafted (S-G) and salt-tolerant pumpkin-grafted (Cucurbita maxima × C. moschata) cucumber seedlings to 80 mM Ca(NO 3 ) 2 stress. Endogenous NO and H 2 O 2 production in S-G seedlings increased in a time-dependent manner, reaching maximum levels after 24 h of Ca(NO 3 ) 2 stress. In contrast, a transient increase in NO production, accompanied by H 2 O 2 accumulation, was observed at 2 h in rootstock-grafted plants. N w -Nitro-l-Arg methyl ester hydrochloride (l-NAME), an inhibitor of nitric oxide synthase (NOS), tungstate, an inhibitor of nitrate reductase (NR), and 2-(4-carboxyphenyl)-4,4,5,5-tetramethy-limidazoline-1-oxyl-3-oxide (cPTIO), a scavenger of NO, were found to significantly inhibit NO accumulation induced by salt stress in rootstock-grafted seedlings. H 2 O 2 production was unaffected by these stress conditions. Ca(NO 3 ) 2 stress-induced NO accumulation was blocked by pretreatment with an H 2 O 2 scavenger (dimethylthiourea, DMTU) and an inhibitor of NADPH oxidase (diphenyleneiodonium, DPI). In addition, maximum quantum yield of PSII (Fv/Fm), as well as the activities and transcript levels of antioxidant enzymes, were significantly decreased by salt stress in rootstock grafted seedlings after pretreatment with these above inhibitors; antioxidant enzyme transcript levels and activities were higher in rootstock-grafted seedlings compared with S-G seedlings. These results suggest that rootstock grafting could alleviate the oxidative damage induced by Ca(NO 3 ) 2 stress in cucumber seedlings, an effect that may be attributable to the involvement of NO in H 2 O 2 -dependent antioxidative metabolism. © 2016 Scandinavian Plant Physiology Society.

On the use of Satellite Remote Sensing and GIS to detect NO2 in the Troposphere

DEFF Research Database (Denmark)

Nielsen, Søren Zebitz

2012-01-01

This thesis studies the spatio-temporal patterns and trends in NO2 air pollution over Denmark using the satellite remote sensing product OMNO2e retrieved from the OMI instrument on the NASA AURA satellite. These data are related to in situ measurements of NO2 made at four rural and four urban...... measured in Denmark. Trends in the data are assessed and declining trends are seen over several European cities, whereas no significant trends are found in the Danish area. The mean distribution of NO2 from the satellite data is also used to evaluate the NOx emission inventory....

Do Transit-Oriented Developments (TODs) and Established Urban Neighborhoods Have Similar Walking Levels in Hong Kong?

Science.gov (United States)

Xiao, Yang; Sarkar, Chinmoy; Zacharias, John

2018-01-01

A sharp drop in physical activity and skyrocketing obesity rate has accompanied rapid urbanization in China. The urban planning concept of transit-oriented development (TOD) has been widely advocated in China to promote physical activity, especially walking. Indeed, many design features thought to promote walking—e.g., mixed land use, densification, and well-connected street network—often characterize both TODs and established urban neighborhoods. Thus, it is often assumed that TODs have similar physical activity benefits as established urban neighborhoods. To verify this assumption, this study compared walking behaviors in established urban neighborhoods and transit-oriented new towns in Hong Kong. To address the limitation of self-selection bias, we conducted a study using Hong Kong citywide public housing scheme, which assigns residents to different housing estates by flat availability and family size rather than personal preference. The results show new town residents walked less for transportation purpose than urban residents. New town residents far from the transit station (800–1200 m) walked less for recreational purpose than TOD residents close to a rail transit station (urban residents. The observed disparity in walking behaviors challenges the common assumption that TOD and established urban neighborhoods have similar impact on walking behavior. The results suggest the necessity for more nuanced planning strategies, taking local-level factors into account to promote walking of TOD residents who live far from transit stations. PMID:29558379

Sustainable urban development and the multi-level transition perspective

DEFF Research Database (Denmark)

Næss, Petter; Vogel, Nina

2012-01-01

This article discusses some challenges and possible adaptations of transition theory as a framework for analyzing the prospects for environmentally more sustainable development of urban land use and transport infrastructure. Rather than depending first and foremost on niche innovations......, a transition toward sustainable urban development is a matter of changing the composition of existing multisegmented land use and transportation regimes. Those well-experienced forms of built environment and transport infrastructure that are in line with sustainability objectives should be strengthened while...... those that are not should be actively constrained and reduced. Urban development in a Danish provincial city is used as a case to illustrate some of the points made in the theoretical part of the article. Due to the wide gap between present conditions and those required to realize a sustainable urban...

Assessing the Potential of Land Use Modification to Mitigate Ambient NO2 and Its Consequences for Respiratory Health

OpenAIRE

Rao, Meenakshi; George, Linda A.; Shandas, Vivek; Rosenstiel, Todd N.

2017-01-01

Understanding how local land use and land cover (LULC) shapes intra-urban concentrations of atmospheric pollutants—and thus human health—is a key component in designing healthier cities. Here, NO2 is modeled based on spatially dense summer and winter NO2 observations in Portland-Hillsboro-Vancouver (USA), and the spatial variation of NO2 with LULC investigated using random forest, an ensemble data learning technique. The NO2 random forest model, together with BenMAP, is further used to develo...

Effect of l-arginine therapy on plasma NO/sub 2/ and NO/sub 3/ levels, and blood pressure in uremic rabbits

International Nuclear Information System (INIS)

Hanif, M.; Khemomal, A.

2011-01-01

Background: Normal kidney function is regulated by Nitric oxide (NO) and Superoxide (O/sub 2/-) in the body, and consequently controls blood pressure. Nitric Oxide promotes natriuresis and diuresis, and therefore results in reduction of blood pressure. The objective of this study was to determine the effect of L-arginine supplementation on blood pressure, urinary protein, nitrite and nitrate in addition to blood urea, serum creatinine and creatinine clearance in uremic rabbits. Methods: This study was carried out in the Department of Biochemistry Basic Medical Sciences Institute, Jinnah Postgraduate Medical Centre, Karachi. A total of 48 rabbits were included in the study. Twenty-four of the rabbits on surgical intervention were prepared as uremic and so became hypertensive as well. Two groups were uremic, one group was given L-arginine and the other was remained untreated. Systolic and diastolic blood pressure was measured on week 0, week 2, week 4, and week 6, while blood and urine was collected on week 0 and week 6. Results: On supplementation with L-arginine to uremic rabbits systolic and diastolic blood pressures were decreased significantly. Nitrite/nitrate and urinary protein were corrected to some extent while blood urea and serum creatinine were unaffected. Conclusion: L-arginine has a beneficial role as blood pressure lowering agent in uremic rabbits. It corrects NO/sub 2/NO/sub 3/ plasma level and proteinuria which is indicator of renal failure. (author)

Incorporating wind availability into land use regression modelling of air quality in mountainous high-density urban environment.

Science.gov (United States)

Shi, Yuan; Lau, Kevin Ka-Lun; Ng, Edward

2017-08-01

Urban air quality serves as an important function of the quality of urban life. Land use regression (LUR) modelling of air quality is essential for conducting health impacts assessment but more challenging in mountainous high-density urban scenario due to the complexities of the urban environment. In this study, a total of 21 LUR models are developed for seven kinds of air pollutants (gaseous air pollutants CO, NO 2 , NO x , O 3 , SO 2 and particulate air pollutants PM 2.5 , PM 10 ) with reference to three different time periods (summertime, wintertime and annual average of 5-year long-term hourly monitoring data from local air quality monitoring network) in Hong Kong. Under the mountainous high-density urban scenario, we improved the traditional LUR modelling method by incorporating wind availability information into LUR modelling based on surface geomorphometrical analysis. As a result, 269 independent variables were examined to develop the LUR models by using the "ADDRESS" independent variable selection method and stepwise multiple linear regression (MLR). Cross validation has been performed for each resultant model. The results show that wind-related variables are included in most of the resultant models as statistically significant independent variables. Compared with the traditional method, a maximum increase of 20% was achieved in the prediction performance of annual averaged NO 2 concentration level by incorporating wind-related variables into LUR model development. Copyright © 2017 Elsevier Inc. All rights reserved.

The global pattern of urbanization and economic growth: evidence from the last three decades.

Science.gov (United States)

Chen, Mingxing; Zhang, Hua; Liu, Weidong; Zhang, Wenzhong

2014-01-01

The relationship between urbanization and economic growth has been perplexing. In this paper, we identify the pattern of global change and the correlation of urbanization and economic growth, using cross-sectional, panel estimation and geographic information systems (GIS) methods. The analysis has been carried out on a global geographical scale, while the timescale of the study spans the last 30 years. The data shows that urbanization levels have changed substantially during these three decades. Empirical findings from cross-sectional data and panel data support the general notion of close links between urbanization levels and GDP per capita. However, we also present significant evidence that there is no correlation between urbanization speed and economic growth rate at the global level. Hence, we conclude that a given country cannot obtain the expected economic benefits from accelerated urbanization, especially if it takes the form of government-led urbanization. In addition, only when all facets are taken into consideration can we fully assess the urbanization process.

The global pattern of urbanization and economic growth: evidence from the last three decades.

Directory of Open Access Journals (Sweden)

Mingxing Chen

Full Text Available The relationship between urbanization and economic growth has been perplexing. In this paper, we identify the pattern of global change and the correlation of urbanization and economic growth, using cross-sectional, panel estimation and geographic information systems (GIS methods. The analysis has been carried out on a global geographical scale, while the timescale of the study spans the last 30 years. The data shows that urbanization levels have changed substantially during these three decades. Empirical findings from cross-sectional data and panel data support the general notion of close links between urbanization levels and GDP per capita. However, we also present significant evidence that there is no correlation between urbanization speed and economic growth rate at the global level. Hence, we conclude that a given country cannot obtain the expected economic benefits from accelerated urbanization, especially if it takes the form of government-led urbanization. In addition, only when all facets are taken into consideration can we fully assess the urbanization process.

Blood lead level in dogs from urban and rural areas of India and its relation to animal and environmental variables

International Nuclear Information System (INIS)

Balagangatharathilagar, M.; Swarup, D.; Patra, R.C.; Dwivedi, S.K.

2006-01-01

Lead is a common environmental pollutant with deleterious health effects on human and animal. Industrial and other human activities enhance the lead level in the environment leading to its higher residues in exposed population. The present study was aimed at determining blood lead concentration in dogs from two urban areas and in surrounding rural areas of India and analyzing lead level in dogs in relation to environmental (urban/ rural) and animal (age, sex, breed and housing) variables. Blood samples were collected from 305 dogs of either sex from urban (n = 277) and unpolluted rural localities (n = 28). Irrespective of breed, age and sex, the urban dogs had significantly (P < 0.01) higher mean blood lead concentration (0.25 ± 0.01 μg/ml) than rural dogs (0.10 ± 0.01 μg/ml). The mean blood lead level in stray dogs either from urban or rural locality (0.27 ± 0.01 μg/ml) was significantly (P < 0.01) higher than that of pets (0.20 ± 0.01 μg/ml), and the blood lead concentration was significantly higher in nondescript dogs (0.25 ± 0.01 μg/ml) than pedigreed dogs (0.20 ± 0.01 μg/ml). The locality (urban/rural) was the major variable affecting blood lead concentration in dogs. Breed and housing of the dogs of urban areas and only housing (pet/stray) in rural areas significantly (P < 0.01) influenced the blood lead concentration in dogs

Intercomparison of measurements of NO2 concentrations in the atmosphere simulation chamber SAPHIR during the NO3Comp campaign

Directory of Open Access Journals (Sweden)

H. Fuchs

2010-01-01

Full Text Available NO2 concentrations were measured by various instruments during the NO3Comp campaign at the atmosphere simulation chamber SAPHIR at Forschungszentrum Jülich, Germany, in June 2007. Analytical methods included photolytic conversion with chemiluminescence (PC-CLD, broadband cavity ring-down spectroscopy (BBCRDS, pulsed cavity ring-down spectroscopy (CRDS, incoherent broadband cavity-enhanced absorption spectroscopy (IBB\\-CEAS, and laser-induced fluorescence (LIF. All broadband absorption spectrometers were optimized for the detection of the main target species of the campaign, NO3, but were also capable of detecting NO2 simultaneously with reduced sensitivity. NO2 mixing ratios in the chamber were within a range characteristic of polluted, urban conditions, with a maximum mixing ratio of approximately 75 ppbv. The overall agreement between measurements of all instruments was excellent. Linear fits of the combined data sets resulted in slopes that differ from unity only within the stated uncertainty of each instrument. Possible interferences from species such as water vapor and ozone were negligible under the experimental conditions.

Green roofs provide habitat for urban bats

Directory of Open Access Journals (Sweden)

K.L. Parkins

2015-07-01

Full Text Available Understanding bat use of human-altered habitat is critical for developing effective conservation plans for this ecologically important taxon. Green roofs, building rooftops covered in growing medium and vegetation, are increasingly important conservation tools that make use of underutilized space to provide breeding and foraging grounds for urban wildlife. Green roofs are especially important in highly urbanized areas such as New York City (NYC, which has more rooftops (34% than green space (13%. To date, no studies have examined the extent to which North American bats utilize urban green roofs. To investigate the role of green roofs in supporting urban bats, we monitored bat activity using ultrasonic recorders on four green and four conventional roofs located in highly developed areas of NYC, which were paired to control for location, height, and local variability in surrounding habitat and species diversity. We then identified bat vocalizations on these recordings to the species level. We documented the presence of five of nine possible bat species over both roof types: Lasiurus borealis, L. cinereus, L. noctivagans, P. subflavus,andE. fuscus. Of the bat calls that could be identified to the species level, 66% were from L. borealis. Overall levels of bat activity were higher over green roofs than over conventional roofs. This study provides evidence that, in addition to well documented ecosystem benefits, urban green roofs contribute to urban habitat availability for several North American bat species.

Intentional injuries in young Ohio children: is there urban/rural variation?

Science.gov (United States)

Anderson, Brit L; Pomerantz, Wendy J; Gittelman, Michael A

2014-09-01

Intentional injuries are the third leading cause of death in children 1 year to 4 years of age. The epidemiology of these injuries based on urban/rural geography and economic variables has not been clearly established. The study purposes are (1) to determine the rate of severe intentional injuries in children younger than 5 years in urban versus rural Ohio counties and (2) to determine if poverty within counties is associated with intentional injury rate. Demographic and injury data on children younger than 5 years who experienced intentional injuries, from January 1, 2003, to December 31, 2011, were extracted retrospectively from the Ohio Trauma Acute Care Registry. We calculated injury rates using the county of residence and US census data. We assigned each county to an urbanization level based on population density (A, most urban; D, most rural). Mean income and percentage of families with children younger than 5 years living below poverty in Ohio counties were obtained from the US census. Rates are per 100,000 children younger than 5 years per year. A total of 984 patients were included; the overall injury rate was 15.9. The mean age was 0.66 years (SD, 1.02 years); 583 (59.2%) were male and 655 (66.6%) were white. One hundred twenty-nine (13.1%) died. Injury rates by urbanization level were as follows: A, 16.5; B, 10.7; C, 18.7; and D, 15.2 (p = 0.285). There were significant associations between county injury rate and mean income (p = 0.05) and percentage of families with children younger than 5 years living below poverty (p = 0.04). We found no association between intentional injury rate and urbanization level in young Ohio children. However, we did find an association between county mean income and percentage of families living below poverty, with intentional injury rate suggesting that financial hardship may be an important risk factor of these injuries.

Impact of the Manaus urban plume on trace gas mixing ratios near the surface in the Amazon Basin: Implications for the NO-NO2-O-3 photostationary state and peroxy radical levels

NARCIS (Netherlands)

Trebs, I.; Mayol-Bracero, O.L.; Pauliquevis, T.; Kuhn, U.; Sander, R.; Ganzeveld, L.N.; Meixner, F.X.; Kesselmeier, J.; Artaxo, P.; Andreae, M.O.

2012-01-01

We measured the mixing ratios of NO, NO2, O-3, and volatile organic carbon as well as the aerosol light-scattering coefficient on a boat platform cruising on rivers downwind of the city of Manaus (Amazonas State, Brazil) in July 2001 (Large-Scale Biosphere-Atmosphere Experiment in

Air quality measurements in urban green areas - a case study

Science.gov (United States)

Kuttler, W.; Strassburger, A.

The influence of traffic-induced pollutants (e.g. CO, NO, NO 2 and O 3) on the air quality of urban areas was investigated in the city of Essen, North Rhine-Westphalia (NRW), Germany. Twelve air hygiene profile measuring trips were made to analyse the trace gas distribution in the urban area with high spatial resolution and to compare the air hygiene situation of urban green areas with the overall situation of urban pollution. Seventeen measurements were made to determine the diurnal concentration courses within urban parks (summer conditions: 13 measurements, 530 30 min mean values, winter conditions: 4 measurements, 128 30 min mean values). The measurements were carried out during mainly calm wind and cloudless conditions between February 1995 and March 1996. It was possible to establish highly differentiated spatial concentration patterns within the urban area. These patterns were correlated with five general types of land use (motorway, main road, secondary road, residential area, green area) which were influenced to varying degrees by traffic emissions. Urban parks downwind from the main emission sources show the following typical temporal concentration courses: In summer rush-hour-dependent CO, NO and NO 2 maxima only occurred in the morning. A high NO 2/NO ratio was established during weather conditions with high global radiation intensities ( K>800 W m -2), which may result in a high O 3 formation potential. Some of the values measured found in one of the parks investigated (Gruga Park, Essen, area: 0.7 km 2), which were as high as 275 μg m -3 O 3 (30-min mean value) were significantly higher than the German air quality standard of 120 μg m -3 (30-min mean value, VDI Guideline 2310, 1996) which currently applies in Germany and about 20% above the maximum values measured on the same day by the network of the North Rhine-Westphalian State Environment Agency. In winter high CO and NO concentrations occur in the morning and during the afternoon rush-hour. The

Microplastic in three urban estuaries, China

International Nuclear Information System (INIS)

Zhao, Shiye; Zhu, Lixin; Li, Daoji

2015-01-01

Estuarine Microplastics (MPs) are limited to know globally. By filtering subsurface water through 330 μm nets, MPs in Jiaojiang, Oujiang Estuaries were quantified, as well as that in Minjiang Estuary responding to Typhoon Soulik. Polymer matrix was analyzed by Raman spectroscopy. MP (<5 mm) comprised more than 90% of total number plastics. The highest MPs density was found in Minjiang, following Jiaojiang and Oujiang. Fibers and granules were the primary shapes, with no pellets found. Colored MPs were the majority. The concentrations of suspended microplastics determine their bioavailability to low trophic organisms, and then possibly promoting the transfer of microplastic to higher trophic levels. Polypropylene and polyethylene were the prevalent types of MPs analyzed. Economic structures in urban estuaries influenced on MPs contamination levels. Typhoon didn't influence the suspended MP densities significantly. Our results provide basic information for better understanding suspended microplastics within urban estuaries and for managerial actions. - Highlights: • Suspended microplastic were investigated within three densely populated/developed urban estuaries, China. • Economical structures may contribute to the abundances of microplastic particles within the studied estuaries. • Typhoon Soulik didn't influence microplastic densities in the water column of Minjiang Estuary. • Microplastics (<5 mm in diameter) dominated more than 90% of the total plastic by number. - Suspended microplastics (MPs) levels were quantified within three urban estuaries, China. MPs densities were consistent with the urban economical structure, and that in Minjiang were unaffected by Typhoon.

Urban Imperviousness Effects on Summer Surface Temperatures Nearby Residential Buildings in Different Urban Zones of Parma

Directory of Open Access Journals (Sweden)

Marco Morabito

2017-12-01

Full Text Available Rapid and unplanned urban growth is responsible for the continuous conversion of green or generally natural spaces into artificial surfaces. The high degree of imperviousness modifies the urban microclimate and no studies have quantified its influence on the surface temperature (ST nearby residential building. This topic represents the aim of this study carried out during summer in different urban zones (densely urbanized or park/rural areas of Parma (Northern Italy. Daytime and nighttime ASTER images, the local urban cartography and the Italian imperviousness databases were used. A reproducible/replicable framework was implemented named “Building Thermal Functional Area” (BTFA useful to lead building-proxy thermal analyses by using remote sensing data. For each residential building (n = 8898, the BTFA was assessed and the correspondent ASTER-LST value (ST_BTFA and the imperviousness density were calculated. Both daytime and nighttime ST_BTFA significantly (p < 0.001 increased when high levels of imperviousness density surrounded the residential buildings. These relationships were mostly consistent during daytime and in densely urbanized areas. ST_BTFA differences between urban and park/rural areas were higher during nighttime (above 1 °C than daytime (about 0.5 °C. These results could help to identify “urban thermal Hot-Spots” that would benefit most from mitigation actions.

Prevalence of household-level food insecurity and its determinants in an urban resettlement colony in north India.

Science.gov (United States)

Chinnakali, Palanivel; Upadhyay, Ravi P; Shokeen, Deepa; Singh, Kavita; Kaur, Manpreet; Singh, Arvind K; Goswami, Anil; Yadav, Kapil; Pandav, Chandrakant S

2014-06-01

An adequate food intake, in terms of quantity and quality, is a key to healthy life. Malnutrition is the most serious consequence of food insecurity and has a multitude of health and economic implications. India has the world's largest population living in slums, and these have largely been underserved areas. The State of Food Insecurity in the World (2012) estimates that India is home to more than 217 million undernourished people. Various studies have been conducted to assess food insecurity at the global level; however, the literature is limited as far as India is concerned. The present study was conducted with the objective of documenting the prevalence of food insecurity at the household level and the factors determining its existence in an urban slum population of northern India. This cross-sectional study was conducted in an urban resettlement colony of South Delhi, India. A pre-designed, pre-tested, semi-structured questionnaire was used for collecting socioeconomic details and information regarding dietary practices. Food insecurity was assessed using Household Food Insecurity Access Scale (HFIAS). Logistic regression analysis was performed to determine the factors associated with food insecurity. A total of 250 women were interviewed through house-to-house survey. Majority of the households were having a nuclear family (61.6%), with mean family-size being 5.5 (SD +/- 2.5) and the mean monthly household income being INR 9,784 (SD +/- 631). Nearly half (53.3%) of the mean monthly household income was spent on food. The study found that a total of 77.2% households were food-insecure, with 49.2% households being mildly food-insecure, 18.8% of the households being moderately food-insecure, and 9.2% of the households being severely food-insecure. Higher education of the women handling food (OR 0.37, 95% CI 0.15-0.92; p insecure. The study demonstrated a high prevalence of food insecurity in the marginalized section of the urban society. The Government of India

Poster abstract: Water level estimation in urban ultrasonic/passive infrared flash flood sensor networks using supervised learning

KAUST Repository

Mousa, Mustafa

2014-04-01

This article describes a machine learning approach to water level estimation in a dual ultrasonic/passive infrared urban flood sensor system. We first show that an ultrasonic rangefinder alone is unable to accurately measure the level of water on a road due to thermal effects. Using additional passive infrared sensors, we show that ground temperature and local sensor temperature measurements are sufficient to correct the rangefinder readings and improve the flood detection performance. Since floods occur very rarely, we use a supervised learning approach to estimate the correction to the ultrasonic rangefinder caused by temperature fluctuations. Preliminary data shows that water level can be estimated with an absolute error of less than 2 cm. © 2014 IEEE.

Do Transit-Oriented Developments (TODs and Established Urban Neighborhoods Have Similar Walking Levels in Hong Kong?

Directory of Open Access Journals (Sweden)

Yi Lu

2018-03-01

Full Text Available A sharp drop in physical activity and skyrocketing obesity rate has accompanied rapid urbanization in China. The urban planning concept of transit-oriented development (TOD has been widely advocated in China to promote physical activity, especially walking. Indeed, many design features thought to promote walking—e.g., mixed land use, densification, and well-connected street network—often characterize both TODs and established urban neighborhoods. Thus, it is often assumed that TODs have similar physical activity benefits as established urban neighborhoods. To verify this assumption, this study compared walking behaviors in established urban neighborhoods and transit-oriented new towns in Hong Kong. To address the limitation of self-selection bias, we conducted a study using Hong Kong citywide public housing scheme, which assigns residents to different housing estates by flat availability and family size rather than personal preference. The results show new town residents walked less for transportation purpose than urban residents. New town residents far from the transit station (800–1200 m walked less for recreational purpose than TOD residents close to a rail transit station (<400 m or urban residents. The observed disparity in walking behaviors challenges the common assumption that TOD and established urban neighborhoods have similar impact on walking behavior. The results suggest the necessity for more nuanced planning strategies, taking local-level factors into account to promote walking of TOD residents who live far from transit stations.

Urban church forests for local temperature regulation: Implications the role of managing and incorporating urban green space in urban planning

Directory of Open Access Journals (Sweden)

Tulu Tolla TURA

2016-11-01

Full Text Available The global surface temperature shows an increment of 0.50.1C per decade and 1.050.3C per century from 1880-2014 with greater increases in cities than non-urban areas. Global communities are shifting towards urbanization due to various factors. Urbanization has caused lack of stable condition for dwellers due to environmental and anthropogenic factors such as land cover changes. Urban temperature rising is the main factors hindering urban dwellers at global level due to insufficient green areas. Social institutions are playing important role in urban greening and urban climate regulation. Ethiopian Orthodox Tewahido Church has long history in indigenous trees biodiversity conservation that plays largely greening role in urban and rural parts of the country. However, there is a research gap in Ethiopia regarding the role of urban green area in the church yards in regulating urban temperature and microclimate change. Therefore, the study evaluated the role of church managed forests in Addis Ababa in regulating surface temperature. Surface temperature inside four church forests at a buffer radius of 0–50 m, 50–100 m, 100–200 m and 200–500 m estimated using Landsat image thermal band 6 of 1986, 2000 and 2010 and ground measurement by ambient thermometer at 10:00 am, 12:30 am and 3:00 pm local time. The ground measurement was done in order to validate satellite image analysis. Plant species diversity, DBH, H, HC, BH and BA was measured. There were 1167 trees in the four studied churches. The mean temperatures of the studied sites were 22.50.1, 23.250.2, 240.6, 24.61.1 and 25.52.2C on site,0–50 m, 50–100 m, 100–200m and 200–500 m respectively for 1986 images; 23.20.5, 23.31.0, 24.32.1, 24.82.2 and 25.51.8C on site, 0-50 m, 50–100 m, 100–200 m and 200–500 m respectively for 2000 images and 23.20.3, 23.270.2, 23.71.6, 241.4 and 24.71.3C on site, 0–50 m, 50–100 m

A candidate framework for PM2.5 source identification in highly industrialized urban-coastal areas

Science.gov (United States)

Mateus, Vinícius Lionel; Gioda, Adriana

2017-09-01

The variability of PM sources and composition impose tremendous challenges for police makers in order to establish guidelines. In urban PM, sources associated with industrial processes are among the most important ones. In this study, a 5-year monitoring of PM2.5 samples was carried out in an industrial district. Their chemical composition was strategically determined in two campaigns in order to check the effectiveness of mitigation policies. Gaseous pollutants (NO2, SO2, and O3) were also monitored along with meteorological variables. The new method called Conditional Bivariate Probability Function (CBPF) was successfully applied to allocate the observed concentration of criteria pollutants (gaseous pollutants and PM2.5) in cells defined by wind direction-speed which provided insights about ground-level and elevated pollution plumes. CBPF findings were confirmed by the Theil-Sen long trend estimations for criteria pollutants. By means of CBPF, elevated pollution plumes were detected in the range of 0.54-5.8 μg m-3 coming from a direction associated to stacks. With high interpretability, the use of Conditional Inference Trees (CIT) provided both classification and regression of the speciated PM2.5 in the two campaigns. The combination of CIT and Random Forests (RF) point out NO3- and Ca+2 as important predictors for PM2.5. The latter predictor mostly associated to non-sea-salt sources, given a nss-Ca2+ contribution equal to 96%.

African urbanization in metropolitan South Africa--differential urbanization perspectives.

Science.gov (United States)

Geyer, H S

1993-07-01

"As a potentially important urban development policy consideration, attention is focused in this paper on differential urbanization trends in South Africa at the metropolitan level. Recent informal urban settlement patterns of the African population within the major metropolitan areas are contrasted against these differential urbanization trends to determine the implications of both for residential development in the metropolitan areas during the post-apartheid era." excerpt

Improving urban African Americans' blood pressure control through multi-level interventions in the Achieving Blood Pressure Control Together (ACT) study: a randomized clinical trial.

Science.gov (United States)

Ephraim, Patti L; Hill-Briggs, Felicia; Roter, Debra L; Bone, Lee R; Wolff, Jennifer L; Lewis-Boyer, LaPricia; Levine, David M; Aboumatar, Hanan J; Cooper, Lisa A; Fitzpatrick, Stephanie J; Gudzune, Kimberly A; Albert, Michael C; Monroe, Dwyan; Simmons, Michelle; Hickman, Debra; Purnell, Leon; Fisher, Annette; Matens, Richard; Noronha, Gary J; Fagan, Peter J; Ramamurthi, Hema C; Ameling, Jessica M; Charlston, Jeanne; Sam, Tanyka S; Carson, Kathryn A; Wang, Nae-Yuh; Crews, Deidra C; Greer, Raquel C; Sneed, Valerie; Flynn, Sarah J; DePasquale, Nicole; Boulware, L Ebony

2014-07-01

Given their high rates of uncontrolled blood pressure, urban African Americans comprise a particularly vulnerable subgroup of persons with hypertension. Substantial evidence has demonstrated the important role of family and community support in improving patients' management of a variety of chronic illnesses. However, studies of multi-level interventions designed specifically to improve urban African American patients' blood pressure self-management by simultaneously leveraging patient, family, and community strengths are lacking. We report the protocol of the Achieving Blood Pressure Control Together (ACT) study, a randomized controlled trial designed to study the effectiveness of interventions that engage patient, family, and community-level resources to facilitate urban African American hypertensive patients' improved hypertension self-management and subsequent hypertension control. African American patients with uncontrolled hypertension receiving health care in an urban primary care clinic will be randomly assigned to receive 1) an educational intervention led by a community health worker alone, 2) the community health worker intervention plus a patient and family communication activation intervention, or 3) the community health worker intervention plus a problem-solving intervention. All participants enrolled in the study will receive and be trained to use a digital home blood pressure machine. The primary outcome of the randomized controlled trial will be patients' blood pressure control at 12months. Results from the ACT study will provide needed evidence on the effectiveness of comprehensive multi-level interventions to improve urban African American patients' hypertension control. Copyright © 2014 Elsevier Inc. All rights reserved.

Benzo[a]pyrene in urban environments of eastern Moscow: pollution levels and critical loads

Science.gov (United States)

Kasimov, Nikolay S.; Kosheleva, Natalia E.; Nikiforova, Elena M.; Vlasov, Dmitry V.

2017-02-01

Polycyclic aromatic hydrocarbons (PAHs), particularly benzo[a]pyrene (BaP), are toxic compounds emitted from various anthropogenic sources. Understanding the BaP concentrations, dynamics and decomposition in soil is required to assess the critical loads of BaP in urban environments. This study is the first attempt to evaluate all major input and output components of benzo[a]pyrene (BaP) balance and to calculate the permissible load on the urban environment in different land-use zones in the Eastern district of Moscow. BaP contamination of the snow cover in the Eastern district of Moscow was related to daily BaP fallout from the atmosphere. In 2010, the mean content of the pollutant in the snow dust was 1942 ng g-1, whereas the average intensity of its fallout was 7.13 ng m-2 per day. Across the territory, BaP winter fallout intensities varied from 0.3 to 1100 ng m-2 per day. The average BaP content in the surface (0-10 cm) soil horizons was 409 ng g-1, which is 83 times higher than the local background value and 20 times higher than the maximum permissible concentration (MPC) accepted in Russia. The variations in soil and snow BaP concentrations among different land-use zones were examined. A significant contribution of BaP from the atmosphere to urban soils was identified. Based on the measurements of BaP atmospheric fallout and BaP reserves in the soils, the critical loads of BaP for the land-use zones in the Eastern district were calculated for different values of degradation intensity and different exposure times. It was established that at an annual degradation intensity of 1-10 %, ecologically safe BaP levels in the soils of all land-use zones, excluding the agricultural zone, will only be reached after many decades or centuries.

Defining the urban area for cross national comparison of health indicators: the EURO-URHIS 2 boundary study.

Science.gov (United States)

Higgerson, James; Birt, Christopher A; van Ameijden, Erik; Verma, Arpana

2017-05-01

Despite much research focusing on the impact of the city condition upon health, there still remains a lack of consensus over what constitutes an urban area (UA). This study was conducted to establish comparable boundaries for the UAs participating in EURO-URHIS 2, and to test whether the sample reflected the heterogeneity of urban living. Key UA contacts ( n = 28) completed a cross-sectional questionnaire, which included where available comparison between Urban Audit city and larger urban zone (LUZ) boundaries and public health administration areas (PHAAs). Additionally, broad health and demographic indicators were sought to test for heterogeneity of the EURO-URHIS 2 sample. Urban Audit city boundaries were found to be suitable for data collection in 100% ( n = 21) of UAs where Urban Audit data were available. The remainder ( n = 7) identified PHAA boundaries akin to the 'city' level. Heterogeneity was observed in the sample for population size and infant mortality rate. Heterogeneity could not be established for male and female life expectancy. This study was able to establish comparable boundaries for EURO-URHIS 2 data collection, with the 'city' area being selected for data collection. The homogeneity of life expectancy indicators was reflective of sub-regional similarities in life expectancy, whilst population estimates and rates of infant mortality indicated the presence of heterogeneity within the sample. Future work would trial these methods with a larger number of indicators and for a larger number of UAs. © The Author 2015. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

Modeling of tropospheric NO2 column over different climatic zones and land use/land cover types in South Asia

Science.gov (United States)

ul-Haq, Zia; Rana, Asim Daud; Tariq, Salman; Mahmood, Khalid; Ali, Muhammad; Bashir, Iqra

2018-03-01

We have applied regression analyses for the modeling of tropospheric NO2 (tropo-NO2) as the function of anthropogenic nitrogen oxides (NOx) emissions, aerosol optical depth (AOD), and some important meteorological parameters such as temperature (Temp), precipitation (Preci), relative humidity (RH), wind speed (WS), cloud fraction (CLF) and outgoing long-wave radiation (OLR) over different climatic zones and land use/land cover types in South Asia during October 2004-December 2015. Simple linear regression shows that, over South Asia, tropo-NO2 variability is significantly linked to AOD, WS, NOx, Preci and CLF. Also zone-5, consisting of tropical monsoon areas of eastern India and Myanmar, is the only study zone over which all the selected parameters show their influence on tropo-NO2 at statistical significance levels. In stepwise multiple linear modeling, tropo-NO2 column over landmass of South Asia, is significantly predicted by the combination of RH (standardized regression coefficient, β = - 49), AOD (β = 0.42) and NOx (β = 0.25). The leading predictors of tropo-NO2 columns over zones 1-5 are OLR, AOD, Temp, OLR, and RH respectively. Overall, as revealed by the higher correlation coefficients (r), the multiple regressions provide reasonable models for tropo-NO2 over South Asia (r = 0.82), zone-4 (r = 0.90) and zone-5 (r = 0.93). The lowest r (of 0.66) has been found for hot semi-arid region in northwestern Indus-Ganges Basin (zone-2). The highest value of β for urban area AOD (of 0.42) is observed for megacity Lahore, located in warm semi-arid zone-2 with large scale crop-residue burning, indicating strong influence of aerosols on the modeled tropo-NO2 column. A statistical significant correlation (r = 0.22) at the 0.05 level is found between tropo-NO2 and AOD over Lahore. Also NOx emissions appear as the highest contributor (β = 0.59) for modeled tropo-NO2 column over megacity Dhaka.

Influence of local meteorology and NO2 conditions on ground-level ozone concentrations in the eastern part of Texas, USA

OpenAIRE

Gorai, A. K.; Tuluri, F.; Tchounwou, P. B.; Ambinakudige, S.

2015-01-01

The influence of local climatic factors on ground-level ozone concentrations is an area of increasing interest to air quality management in regards to future climate change. This study presents an analysis on the role of temperature, wind speed, wind direction, and NO2 level on ground-level ozone concentrations over the region of Eastern Texas, USA. Ozone concentrations at the ground level depend on the formation and dispersion processes. Formation process mainly depends on the precursor sour...

Strategies for Sustainable Urban Development and Urban-Rural Linkages

DEFF Research Database (Denmark)

Nilsson, Kjell; Nielsen, Thomas Alexander Sick; Aalbers, Carmen

2014-01-01

, identified how land use conflicts and the pressure towards peri- urban areas can be strategically managed in different development and regulatory contexts. To summarise, the following strategies were identified as important steps towards more sustainable urban-rural futures: (i) better coordination...... of transport, land use and open space planning; (ii) urban containment and densification – development a green compact city; (iii) preservation of blue and green infrastructure; and (iv) preservation of agricultural land and the promotion of local production. The need also remains to strengthen governance...... at the regional level while at the pan-European level there is clearly a need for more policy attention to be given to urban-rural linkages....

Atmospheric carbon reduction by urban trees

International Nuclear Information System (INIS)

Nowak, D.J.

1993-01-01

Trees, because they sequester atmospheric carbon through their growth process and conserve energy in urban areas, have been suggested as one means to combat increasing levels of atmospheric carbon. Analysis of the urban forest in Oakland, California (21% tree cover), reveals a tree carbon storage level of 11·0 metric tons/hectare. Trees in the area of the 1991 fire in Oakland stored approximately 14,500 metric tons of carbon, 10% of the total amount stored by Oakland's urban forest. National urban forest carbon storage in the United States (28% tree cover) is estimated at between 350 and 750 million metric tons. Establishment of 10 million urban trees annually over the next 10 years is estimated to sequester and offset the production of 363 million metric tons of carbon over the next 50 years-less than 1% of the estimated carbon emissions in the United States over the same time period. Advantages and limitations of managing urban trees to reduce atmospheric carbon are discussed. 36 refs., 2 figs., 3 tabs

Using Agent-Based Modeling to Enhance System-Level Real-time Control of Urban Stormwater Systems

Science.gov (United States)

Rimer, S.; Mullapudi, A. M.; Kerkez, B.

2017-12-01

The ability to reduce combined-sewer overflow (CSO) events is an issue that challenges over 800 U.S. municipalities. When the volume of a combined sewer system or wastewater treatment plant is exceeded, untreated wastewater then overflows (a CSO event) into nearby streams, rivers, or other water bodies causing localized urban flooding and pollution. The likelihood and impact of CSO events has only exacerbated due to urbanization, population growth, climate change, aging infrastructure, and system complexity. Thus, there is an urgent need for urban areas to manage CSO events. Traditionally, mitigating CSO events has been carried out via time-intensive and expensive structural interventions such as retention basins or sewer separation, which are able to reduce CSO events, but are costly, arduous, and only provide a fixed solution to a dynamic problem. Real-time control (RTC) of urban drainage systems using sensor and actuator networks has served as an inexpensive and versatile alternative to traditional CSO intervention. In particular, retrofitting individual stormwater elements for sensing and automated active distributed control has been shown to significantly reduce the volume of discharge during CSO events, with some RTC models demonstrating a reduction upwards of 90% when compared to traditional passive systems. As more stormwater elements become retrofitted for RTC, system-level RTC across complete watersheds is an attainable possibility. However, when considering the diverse set of control needs of each of these individual stormwater elements, such system-level RTC becomes a far more complex problem. To address such diverse control needs, agent-based modeling is employed such that each individual stormwater element is treated as an autonomous agent with a diverse decision making capabilities. We present preliminary results and limitations of utilizing the agent-based modeling computational framework for the system-level control of diverse, interacting

CO2 emission inventories for Chinese cities in highly urbanized areas compared with European cities

International Nuclear Information System (INIS)

Yu Wei; Pagani, Roberto; Huang Lei

2012-01-01

The international literature has paid significant attention to presenting China as the largest emitter of greenhouse gases (GHGs) in the world, despite having much lower per-capita emissions than the global average. In fact, the imbalance of economic development leads to diversity in GHG emissions profiles in different areas of China. This paper employs a common methodology, consistent with the Sustainable Energy Action Plan (SEAP) approved by the Covenant of Mayors (CoM), to estimate CO 2 emissions of four Chinese cities in highly urbanized areas from 2004 to 2010. The results show that the CO 2 emissions of all four cities are still rising and that secondary industries emit the most CO 2 in these cities. By comparing these data with the inventory results of two European cities, this paper further reveals that Chinese cities in highly urbanized areas contribute much higher per-capita emissions than their European competitors. Furthermore, the per-capita CO 2 emissions of the residential sector and private transport in these Chinese cities are growing rapidly, some of them approaching the levels of European cities. According to these findings, several policy suggestions considering regional disparities are provided that aim to reduce the CO 2 emissions of highly urbanized areas in China. - Highlights: ► An exemplary study of GHG emission inventory for Chinese cities. ► Estimate CO 2 emissions of Chinese city in highly urbanized areas from 2004 to 2010. ► The studied Chinese cities contribute higher per-capita emissions than European’s. ► Emissions of residential sector and private transport in China are growing rapidly. ► Several policy suggestions considering regional disparities are provided.

Population, migration and urbanization.

Science.gov (United States)

1982-06-01

Despite recent estimates that natural increase is becoming a more important component of urban growth than rural urban transfer (excess of inmigrants over outmigrants), the share of migration in the total population growth has been consistently increasing in both developed and developing countries. From a demographic perspective, the migration process involves 3 elements: an area of origin which the mover leaves and where he or she is considered an outmigrant; the destination or place of inmigration; and the period over which migration is measured. The 2 basic types of migration are internal and international. Internal migration consists of rural to urban migration, urban to urban migration, rural to rural migration, and urban to rural migration. Among these 4 types of migration various patterns or processes are followed. Migration may be direct when the migrant moves directly from the village to the city and stays there permanently. It can be circular migration, meaning that the migrant moves to the city when it is not planting season and returns to the village when he is needed on the farm. In stage migration the migrant makes a series of moves, each to a city closer to the largest or fastest growing city. Temporary migration may be 1 time or cyclical. The most dominant pattern of internal migration is rural urban. The contribution of migration to urbanization is evident. For example, the rapid urbanization and increase in urban growth from 1960-70 in the Republic of Korea can be attributed to net migration. In Asia the largest component of the population movement consists of individuals and groups moving from 1 rural location to another. Recently, because urban centers could no longer absorb the growing number of migrants from other places, there has been increased interest in the urban to rural population redistribution. This reverse migration also has come about due to slower rates of employment growth in the urban centers and improved economic opportunities

Republic of India : Service Level Benchmarking, Citizen Voice and Performance Improvement Strategies in Urban Water Supply and Sanitation

OpenAIRE

World Bank Group

2016-01-01

This synthesis report details the process, outputs and intermediate outcomes of the Water and Sanitation Program - World Bank (WSP) Technical Assistance (TA) to Service Level Benchmarking, Citizen Voice and Performance Improvement Strategies in Urban Water Supply and Sanitation (UWSS) in India. This technical assistance (TA) sought to strengthen accountability for service outcomes in urban...

Disparities in Prevalence of Cardiometablic Risk Factors in Rural, Urban-Poor, and Urban-Middle Class Women in India.

Directory of Open Access Journals (Sweden)

Indu Mohan

Full Text Available Urbanization is an important determinant of cardiovascular disease (CVD risk. To determine location-based differences in CVD risk factors in India we performed studies among women in rural, urban-poor and urban middle-class locations.Population-based cross-sectional studies in rural, urban-poor, and urban-middle class women (35-70 y were performed at multiple sites. We evaluated 6853 women (rural 2616, 5 sites; urban-poor 2008, 4 sites; urban middle-class 2229, 11 sites for socioeconomic, lifestyle, anthropometric and biochemical risk factors. Descriptive statistics are reported.Mean levels of body mass index (BMI, waist circumference, waist-hip ratio (WHR, systolic BP, fasting glucose and cholesterol in rural, urban-poor and urban-middle class women showed significantly increasing trends (ANOVAtrend, p 80 cm (28.3, 63.4, 61.9%, waist >90 cm (8.4, 31.4, 38.2%, waist hip ratio (WHR >0.8 (60.4, 90.7, 88.5, WHR>0.9 (13.0, 44.3, 56.1%, hypertension (31.6, 48.2, 59.0% and hypercholesterolemia (13.5, 27.7, 37.4% (Mantel Haenszel X2 ptrend <0.01. Inverse trend was observed for tobacco use (41.6, 19.6, 9.4%. There was significant association of hypertension, hypercholesterolemia and diabetes with overweight and obesity (adjusted R2 0.89-0.99.There are significant location based differences in cardiometabolic risk factors in India. The urban-middle class women have the highest risk compared to urban-poor and rural.

Spatial and temporal distribution of onroad CO2 emissions at the Urban spatial scale

Science.gov (United States)

Song, Y.; Gurney, K. R.; Zhou, Y.; Mendoza, D. L.

2011-12-01

The Hestia Project is a multi-disciplinary effort to help better understand the spatial and temporal distribution of fossil fuel carbon dioxide (CO2) emission at urban scale. Onroad transportation is an essential source of CO2 emissions. This study examines two urban domains: Marion County (Indianapolis) and Los Angeles County and explores the methods and results associated with the spatial and temporal distribution of local urban onroad CO2 emissions. We utilize a bottom-up approach and spatially distribute county emissions based on the Annual Average Daily Traffic (AADT) counts provided by local Department of Transportation. The total amount of CO2 emissions is calculated by the National Mobile Inventory Model (NMIM) for Marion County and the EMission FACtors (EMFAC) model for Los Angeles County. The NMIM model provides CO2 emissions based on vehicle miles traveled (VMT) data at the county-level from the national county database (NCD). The EMFAC model provides CO2 emissions for California State based on vehicle activities, including VMT, vehicle population and fuel types. A GIS road atlas is retrieved from the US Census Bureau. Further spatial analysis and integration are performed by GIS software to distribute onroad CO2 emission according to the traffic volume. The temporal allocation of onroad CO2 emission is based on the hourly traffic data obtained from the Metropolitan Planning Orgnizations (MPO) for Marion County and Department of Transportation for Los Angeles County. The annual CO2 emissions are distributed according to each hourly fraction of traffic counts. Due to the fact that ATR stations are unevenly distributed in space, we create Thiessen polygons such that each road segment is linked to the nearest neighboring ATR station. The hourly profile for each individual station is then combined to create a "climatology" of CO2 emissions in time on each road segment. We find that for Marion County in the year 2002, urban interstate and arterial roads have

Natural gas consumption, income, urbanization, and CO2 emissions in China and India.

Science.gov (United States)

Solarin, Sakiru Adebola; Lean, Hooi Hooi

2016-09-01

The objective of this study is to examine the impact of natural gas consumption, output, and urbanization on CO2 emission in China and India for the period, 1965-2013. A cointegraton test, which provides for endogenously determined structural breaks, has been applied to examine the long-run relationship and to investigate the presence of environmental Kuznets curve (EKC) in the two countries. The presence of causal relationship between the variables is also investigated. The findings show that there is a long-run relationship in the variables and natural gas, real GDP, and urbanization have long-run positive impact on emission in both countries. There is no evidence for EKC in China and India. The findings further suggest that there is a long-run feedback relationship between the variables. The policy inferences of these findings are discussed.

Some structural aspects of urbanization in Ethiopia.

Science.gov (United States)

Rafiq, M; Hailemariam, A

1987-07-01

This article studies the emerging patterns of urbanization in Ethiopia. Over the period from 1967-1984, a number of structural changes have occurred which are likely to play a dominant role in the future urban growth in Ethiopia. In spite of its long history of settled population, Ethiopia did not witness sustained growth of urban centers. Ethiopia is 1 of the least urbanized areas in the Third World. A 3rd aspect of urbanization in Ethiopia is the wide range of regional differentials in the level of urbanization. Most of the urban population is concentrated in 2 administrative regions--Shoa and Eritrea. A more balanced urban growth may, inter alia, involve a better spread in terms of higher education, industrialization, provision of health and social services, and the development of communication and commercial infrastructure. Another striking feature of urbanization in Ethiopia is that growth has not been disproportionately concentrated in the largest urban centers. The largest urban centers have not assumed an inordinately higher level of primacy. The basic form of the curve depicting the relationship between the size of a locality and its rank has remained unchanged over the period. The post-revolution land reforms and the new socioeconomic structure emerging from reorganization of the society appear to have a rural-urban migration inhibiting effect. Some of the country's regional differentials may be associated with environmental factors.

NO and H2O2 contribute to SO2 toxicity via Ca2+ signaling in Vicia faba guard cells.

Science.gov (United States)

Yi, Min; Bai, Heli; Xue, Meizhao; Yi, Huilan

2017-04-01

NO and H 2 O 2 have been implicated as important signals in biotic and abiotic stress responses of plants to the environment. Previously, we have shown that SO 2 exposure increased the levels of NO and H 2 O 2 in plant cells. We hypothesize that, as signaling molecules, NO and H 2 O 2 mediate SO 2 -caused toxicity. In this paper, we show that SO 2 hydrates caused guard cell death in a concentration-dependent manner in the concentration range of 0.25 to 6 mmol L -1 , which was associated with elevation of intracellular NO, H 2 O 2 , and Ca 2+ levels in Vicia faba guard cells. NO donor SNP enhanced SO 2 toxicity, while NO scavenger c-PTIO and NO synthesis inhibitors L-NAME and tungstate significantly prevented SO 2 toxicity. ROS scavenger ascorbic acid (AsA) and catalase (CAT), Ca 2+ chelating agent EGTA, and Ca 2+ channel inhibitor LaCl 3 also markedly blocked SO 2 toxicity. In addition, both c-PTIO and AsA could completely block SO 2 -induced elevation of intracellular Ca 2+ level. Moreover, c-PTIO efficiently blocked SO 2 -induced H 2 O 2 elevation, and AsA significantly blocked SO 2 -induced NO elevation. These results indicate that extra NO and H 2 O 2 are produced and accumulated in SO 2 -treated guard cells, which further activate Ca 2+ signaling to mediate SO 2 toxicity. Our findings suggest that both NO and H 2 O 2 contribute to SO 2 toxicity via Ca 2+ signaling.

Can TiO2-based photocatalytic textiles be used to improve the urban air quality?

Science.gov (United States)

Ródenas, Mila; Fages, Eduardo; Fatarella, Enrico; Herrero, David; Castagnoli, Lidia; Borràs, Esther; Vera, Teresa; Gómez, Tatiana; Catota, Marlon; Carreño, Javier; Hernández, Daniel; Gimeno, Cristina; López, Ramón; Muñoz, Amalia

2017-04-01

Despite current legislation and efforts made to improve urban air quality, significant negative effects still persist. That is the case of traffic, which impact on air pollution is a growing problem. For this reason, depollution measures are necessary to reach safer air quality levels. Recently, the use of titanium dioxide (TiO2) based photocatalytic self-cleaning and de-polluting materials has been considered to remove air pollutants, especially NOx. TiO2 can be found in the market under different formats for environmental purposes, and its effectiveness depends not only on the support (concrete, paints, etc) but also on the impregnation method (layer, embedded, etc). By combining laboratory and field campaigns, the LIFE PHOTOCITYTEX project was conceived to demonstrate the effectiveness of using TiO2-based photocatalytic nanomaterials in textiles as a way of alleviating the air pollution in urban areas. Within the project, which is already within its last year, two one-year extensive passive dosimetric campaigns have already been completed to assess their impact on the selected urban sites, measuring before and after the installation of the photocatalytic textile prototypes, respectively. Also, intensive active measurement campaigns (using active dosimetry, monitors and instrumentation for physical parameters) have been conducted to account for winter and summer conditions. Besides, lab-tests have been concluded to determine optimal photocatalytic formulations on textiles, and these have been tested at the EUPHORE simulation chambers under typical environmental conditions of various European cities. Besides the effect on NOx, which has been the main focus of the study, VOCs formation and abatement has been assessed, yielding in a better overall understanding of the whole process and its implications. Very promising results on the deep reduction of NOx have been observed at EUPHORE. From the calculation of the uptake coefficient, a mathematical model tool foresees

Contamination of urban garden soils with copper, boron, and lead

Energy Technology Data Exchange (ETDEWEB)

Purves, D

1967-04-01

Spectrochemical analysis of representative samples of topsoil from urban gardens and from individual fields in rural areas indicates that the level of total copper, EDTA-extractable copper, water-soluble boron, and acetic-acid extractable lead are markedly enhanced in urban areas. No significant differences were discovered between levels of these elements in soils from built-up areas in small towns and large conurbations. These results suggest the possibility of general enhancement of the trace element content of plants grown in private gardens in built-up areas.

Estimating the Returns to Urban Boarding Schools: Evidence from SEED. NBER Working Paper No. 16746

Science.gov (United States)

Curto, Vilsa E.; Fryer, Roland G., Jr.

2011-01-01

The SEED schools, which combine a "No Excuses'' charter model with a five-day-a-week boarding program, are America's only urban public boarding schools for the poor. We provide the first causal estimate of the impact of attending SEED schools on academic achievement, with the goal of understanding whether changing a student's environment through…

Total and Bioaccessible Soil Arsenic and Lead Levels and Plant Uptake in Three Urban Community Gardens in Puerto Rico

Science.gov (United States)

Arsenic (As) and lead (Pb) are two contaminants of concern associated with urban gardening. In Puerto Rico, data currently is limited on As and Pb levels in urban garden soils, soil metal (loid) bioaccessibility, and uptake of As and Pb in soil by edible plants grown in the regio...

Life cycle analysis of urban infrastructures; Toshi infrastructure seibi no lifecycle bunseki

Energy Technology Data Exchange (ETDEWEB)

Tagashira, N.; Uchiyama, Y. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

1997-05-01

Power supply services, city gas supply services, water supply and drainage services, roads, and buildings were treated as urban infrastructures so as to grasp the resources and CO2 emission consumed in their life cycle. Moreover, the consumption of resources for supporting one person and the emission of CO2 were analyzed to clarify an important point for resource saving and environmental load reduction. The resources used and CO2 emitted for each urban infrastructure were calculated with Kanto districts as a target. For the annual material weight a person, buildings are about 1,200 kg, roads are about 560 kg, and city gas is about 170 kg. Water supply and drainage is about 68 kg, and electric power is about 57 kg. For the annual CO2 emission a person, buildings are about 120 kg-C, roads are about 13 kg-C, and electric power is about 6.6 kg-C. City gas is about 5.3 kg-C, and water supply and drainage is about 4.4 kg-C. In the material weight for each resource, gravel, crushed stone, concrete, and asphalt concrete have a high consumption rate. In CO2 emission, iron, concrete, and gas oil form a high rate. 21 refs., 26 figs., 2 tabs.

Beyond urban penalty and urban sprawl: back to living conditions as the focus of urban health.

Science.gov (United States)

Freudenberg, Nicholas; Galea, Sandro; Vlahov, David

2005-02-01

Researchers have long studied urban health, both to describe the consequences of urban living and to design interventions to promote the health of people living in cities. Two approaches to understanding the impact of cities on health have been dominant, namely, urban health penalty and urban sprawl. The urban penalty approach posits that cities concentrate poor people and expose them to unhealthy physical and social environments. Urban sprawl focuses on the adverse health and environmental effects of urban growth into outlying areas. We propose a model that integrates these approaches and emphasizes urban living conditions as the primary determinant of health. The aim of the model is to move beyond describing the health-related characteristics of various urban populations towards identifying opportunities for intervention. Such a shift in framework enables meaningful comparisons that can inform public health activities at the appropriate level and evaluate their effectiveness in improving the health of urban populations. The model is illustrated with two examples from current urban public health practice.

Unsustaineble pseudo-urban consequences of legal and urban terminology

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Ćerimović Velimir Lj.

2011-01-01

Full Text Available City planning is a complex task and through this work we face the space and natural resources that expose the exploitation (that are to be exploited and prone to unsustainable change. Often without environmental responsibility and the imperative of creating certain measures we make superstructure no matter how much the environment may be disrupted, and whether such relationships create a better society, better network of urban settlements and a better man. At that may also affect our knowledge which is often due to a variety of doctrines and legislative regulations that are applied in the planning and management space. From this it can be seen that modern architecture did not contribute to the creation of better cities. Also, urban planning is mainly restricted to the regulation and it neglected the creative action, regional-planning is lost in theoretical research, while the consideration of the whole problem is abandoned. In addition to this, in today’s transitional terms and the domineering (dominant urban crisis unsustainable combination and identification of the “2D” and the “3D” terminology is recognizable, which is only indicators that in the field of urban planning some transitional trends are prevailing. This unsustainable state of affairs in the transitional planning of urban areas can be applied in the most suitable way to pseudo-urbanization, sub-urbanization, unbalanced eco-reciprocity, non-standard construction of the urban tissue, discontinuity inherited and newly constructed urban substance. In this regard, consequently expressed negative environmental legacy of reproduction and the increased effect of the negative consequences of greenhouse gases from the threatening climate change, only shows that urban planners are not sinless and, they more or less (unconsciously complicit and participate in the contamination of urban and environment. In the end, it definitely guides us to the need to leave or transformation of the

Potential effects of using biodiesel in road-traffic on air quality over the Porto urban area, Portugal

Science.gov (United States)

Ribeiro, Isabel; Monteiro, Alexandra; Lopes, Myriam

2016-01-01

This work aims to assess the impacts of biodiesel blends use in road-traffic on air quality. In this frame, the air quality numerical modelling system WRF-EURAD was applied over Portugal and the Porto urban area, forced by two emission scenarios (including CO, NOx, PM10, PM2.5, NMVOC, formaldehyde, acetaldehyde, acrolein and benzene): a reference scenario, without biofuels, and a scenario where a B20 fuel (20% biodiesel/80% diesel, v/v) is used by the diesel vehicle fleet. Regarding carbonyl compounds, emission scenarios pointed out that B20 fuel can promote an increase of 20% on formaldehyde, acetaldehyde and acrolein emissions, leading to increments on equivalent ozone production. On the other hand, through the air quality modelling exercise, it was verified that the use of B20 helps in controlling air pollution, improving CO and NO2 concentrations in urban airshed in about 20% and 10%, respectively, taking into account a regional simulation grid. However, according to the urban scale simulation, NO2 levels can increase in about 1%, due to the use of B20, over the Porto urban area. For the remaining studied pollutants, namely PM10 and PM2.5, mean concentrations will be reduced all over the territory, however in a negligible amount of <1%.

Joint Costs in Electricity and Natural Gas Distribution Infrastructures: The Role of Urban Factors

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Muzeyyen Anil Senyel

2018-04-01

Full Text Available This paper analyzes the joint cost structure of electricity and natural gas distribution investments. Assessing the joint costs is critical for urban development and public policy regarding competition at the local level. The paper accounts for the urban and geographic factors at the local level, while the previous literature primarily used company-level data with a few or no site-specific variables in joint cost analyses. An empirical analysis of the multi-utility capital costs suggests that the local urban and geographic conditions affect such costs, with economies of scope present in electricity and natural gas both in terms of total costs and underground investment costs. Hence, the joint service provision makes economic and environmental sense for urban policy makers.

N=2 no-scale supergravity

Energy Technology Data Exchange (ETDEWEB)

Itoyama, H.; McLerran, L.; Taylor, T.R.; Van der Bij, J.J.

1987-01-12

N=2 extended supergravity is discussed and an assessment is made of the problems encountered in applying it to the construction of phenomenological models of particle physics. A specific class of so-called no-scale models is discussed, in which the two supersymmetries are spontaneously broken in flat space-time, with naturally vanishing cosmological constant and the symmetry breaking undetermined at the classical level. Supergravity-induced supersymmetry breaking generates effective mass terms for spin-1/2 components of the vector gauge multiplets and spin-0 components of the scalar matter multiplets. For finite globally supersymmetric models, this supersymmetry breaking preserves the finiteness. Possible connections of N=2 no-scale supergravity with superstrings and finite range antigravity are mentioned.

N=2 no-scale supergravity

International Nuclear Information System (INIS)

Itoyama, H.; McLerran, L.; Taylor, T.R.; Van der Bij, J.J.

1987-01-01

N=2 extended supergravity is discussed and an assessment is made of the problems encountered in applying it to the construction of phenomenological models of particle physics. A specific class of so-called no-scale models is discussed, in which the two supersymmetries are spontaneously broken in flat space-time, with naturally vanishing cosmological constant and the symmetry breaking undetermined at the classical level. Supergravity-induced supersymmetry breaking generates effective mass terms for spin-1/2 components of the vector gauge multiplets and spin-0 components of the scalar matter multiplets. For finite globally supersymmetric models, this supersymmetry breaking preserves the finiteness. Possible connections of N=2 no-scale supergravity with superstrings and finite range antigravity are mentioned. (orig.)

Impacts of Urban Transportation Mode Split on CO2 Emissions in Jinan, China

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Kebin He

2011-04-01

Full Text Available As the world’s largest developing country, China currently is undergoing rapid urbanization and motorization, which will result in far-reaching impacts on energy and the environment. According to estimates, energy use and carbon emissions in the transportation sector will comprise roughly 30% of total emissions by 2030. Since the late 1990s, transportation-related issues such as energy, consumption, and carbon emissions have become a policy focus in China. To date, most research and policies have centered on vehicle technologies that promote vehicle efficiency and reduced emissions. Limited research exists on the control of greenhouse gases through mode shifts in urban transportation—in particular, through the promotion of public transit. The purpose of this study is to establish a methodology to analyze carbon emissions from the urban transportation sector at the Chinese city level. By using Jinan, the capital of China’s Shandong Province, as an example, we have developed an analytical model to simulate energy consumption and carbon emissions based on the number of trips, the transportation mode split, and the trip distance. This model has enabled us to assess the impacts of the transportation mode split on energy consumption and carbon emissions. Furthermore, this paper reviews a set of methods for data collection, estimation, and processing for situations where statistical data are scarce in China. This paper also describes the simulation of three transportation system development scenarios. The results of this study illustrate that if no policy intervention is implemented for the transportation mode split (the business-as-usual (BAU case, then emissions from Chinese urban transportation systems will quadruple by 2030. However, a dense, mixed land-use pattern, as well as transportation policies that encourage public transportation, would result in the elimination of 1.93 million tons of carbon emissions—approximately 50% of the BAU

Characteristics of surface ozone and nitrogen oxides at urban, suburban and rural sites in Ningbo, China

Science.gov (United States)

Tong, Lei; Zhang, Huiling; Yu, Jie; He, Mengmeng; Xu, Nengbin; Zhang, Jingjing; Qian, Feizhong; Feng, Jiayong; Xiao, Hang

2017-05-01

Surface ozone (O3) is a harmful air pollutant that has attracted growing concern in China. In this study, the mixing ratios of O3 and nitrogen oxides (NOx) at three different sites (urban, suburban and rural) of Ningbo were continuously measured to investigate the spatiotemporal characteristics of O3 and its relationships with environmental variables. The diurnal O3 variations were characterized by afternoon maxima (38.7-53.1 ppb on annual average) and early morning minima (11.7-26.2 ppb) at all the three sites. Two seasonal peaks of O3 were observed in spring (April or May) and autumn (October) with minima being observed in winter (December). NOx levels showed generally opposite variations to that of O3 with diurnal and seasonal maxima occurring in morning/evening rush-hours and in winter, respectively. As to the inter-annual variations of air pollutants, generally decreasing and increasing trends were observed in NO and O3 levels, respectively, from 2012 to 2015 at both urban and suburban sites. O3 levels were positively correlated with temperature but negatively correlated with relative humidity and NOx levels. Significant differences in O3 levels were observed for different wind speeds and wind directions (p variation, higher levels of O3 were observed at the suburban and rural sites where less O3 was depleted by NO titration. In contrast, the urban site exhibited lower O3 but higher NOx levels due to the influence of traffic emissions. Larger amplitudes of diurnal and monthly O3 variations were observed at the suburban site than those at the urban and rural sites. In general, the O3 levels at the non-urban sites were more affected by the background transport, while both the local and regional contributions played roles in urban O3 variations. The annual average O3 mixing ratios (22.7-37.7 ppb) in Ningbo were generally similar to those of other regions around the world. However, the recommended air quality standards for O3 were often exceeded during warm

Large eddy simulation of reactive pollutants in a deep urban street canyon: Coupling dynamics with O3-NOx-VOC chemistry.

Science.gov (United States)

Zhong, Jian; Cai, Xiao-Ming; Bloss, William James

2017-05-01

A large eddy simulation (LES) model coupled with O 3 -NO x -VOC chemistry is implemented to simulate the coupled effects of emissions, mixing and chemical pre-processing within an idealised deep (aspect ratio = 2) urban street canyon under a weak wind condition. Reactive pollutants exhibit significant spatial variations in the presence of two vertically aligned unsteady vortices formed in the canyon. Comparison of the LES results from two chemical schemes (simple NO x -O 3 chemistry and a more comprehensive Reduced Chemical Scheme (RCS) chemical mechanism) shows that the concentrations of NO 2 and O x inside the street canyon are enhanced by approximately 30-40% via OH/HO 2 chemistry. NO, NO x , O 3 , OH and HO 2 are chemically consumed, while NO 2 and O x (total oxidant) are chemically produced within the canyon environment. Within-canyon pre-processing increases oxidant fluxes from the canyon to the overlying boundary layer, and this effect is greater for deeper street canyons (as found in many traditional European urban centres) than shallower (lower aspect ratio) streets. There is clear evidence of distinct behaviours for emitted chemical species and entrained chemical species, and positive (or negative) values of intensities of segregations are found between pairs of species with similar (or opposite) behaviour. The simplified two-box model underestimated NO and O 3 levels, but overestimated NO 2 levels for both the lower and upper canyon compared with the more realistic LES-chemistry model. This suggests that the segregation effect due to incomplete mixing reduces the chemical conversion rate of NO to NO 2 . This study reveals the impacts of nonlinear O 3 -NO x -VOC photochemical processes in the incomplete mixing environment and provides a better understanding of the pre-processing of emissions within canyons, prior to their release to the urban boundary layer, through the coupling of street canyon dynamics and chemistry. Copyright © 2017 Elsevier Ltd

Rural-urban comparisons of dengue seroprevalence in Malaysia

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Cheng Hoon Chew

2016-08-01

Full Text Available Abstract Background Each year an estimated 390 million dengue infections occur worldwide. In Malaysia, dengue is a growing public health concern but estimate of its disease burden remains uncertain. We compared the urban-rural difference of dengue seroprevalence and determined age-specific dengue seroprevalence in Malaysia. Methods We undertook analysis on 11,821 subjects from six seroprevalence surveys conducted in Malaysia between 2001 and 2013, which composed of five urban and two rural series. Results Prevalence of dengue increased with age in both urban and rural locations in Malaysia, which exceeded 90 % among those aged 70 years or beyond. The age-specific rates of the 5 urban surveys overlapped without clear separation among them, while prevalence was lower in younger subjects in rural series than in urban series, the trend reversed in older subjects. There were no differences in the seroprevalence by gender, ethnicity or region. Poisson regression model confirmed the prevalence have not changed in urban areas since 2001 but in rural areas, there was a significant positive time trend such that by year 2008, rural prevalence was as high as in urban areas. Conclusion Dengue seroprevalence has stabilized but persisted at a high level in urban areas since 2001, and is fast stabilizing in rural areas at the same high urban levels by 2008. The cumulative seroprevalence of dengue exceeds 90 % by the age of 70 years, which translates into 16.5 million people or 55 % of the total population in Malaysia, being infected by dengue by 2013.

Rural-urban comparisons of dengue seroprevalence in Malaysia.

Science.gov (United States)

Chew, Cheng Hoon; Woon, Yuan Liang; Amin, Faridah; Adnan, Tassha H; Abdul Wahab, Asmah Hani; Ahmad, Zul Edzhar; Bujang, Mohd Adam; Abdul Hamid, Abdul Muneer; Jamal, Rahman; Chen, Wei Seng; Hor, Chee Peng; Yeap, Lena; Hoo, Ling Ping; Goh, Pik Pin; Lim, Teck Onn

2016-08-18

Each year an estimated 390 million dengue infections occur worldwide. In Malaysia, dengue is a growing public health concern but estimate of its disease burden remains uncertain. We compared the urban-rural difference of dengue seroprevalence and determined age-specific dengue seroprevalence in Malaysia. We undertook analysis on 11,821 subjects from six seroprevalence surveys conducted in Malaysia between 2001 and 2013, which composed of five urban and two rural series. Prevalence of dengue increased with age in both urban and rural locations in Malaysia, which exceeded 90 % among those aged 70 years or beyond. The age-specific rates of the 5 urban surveys overlapped without clear separation among them, while prevalence was lower in younger subjects in rural series than in urban series, the trend reversed in older subjects. There were no differences in the seroprevalence by gender, ethnicity or region. Poisson regression model confirmed the prevalence have not changed in urban areas since 2001 but in rural areas, there was a significant positive time trend such that by year 2008, rural prevalence was as high as in urban areas. Dengue seroprevalence has stabilized but persisted at a high level in urban areas since 2001, and is fast stabilizing in rural areas at the same high urban levels by 2008. The cumulative seroprevalence of dengue exceeds 90 % by the age of 70 years, which translates into 16.5 million people or 55 % of the total population in Malaysia, being infected by dengue by 2013.

Assessing theEffects of Nitrogen Dioxide in Urban Air on Health of West and Southwest Cities of Iran

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Zallaghi

2014-10-01

2011. Higher RR value can depict mismanagement in urban air quality. The lower level of RR value might be achieved if some control strategies for reducing NO2 emission were used.

Volume 7 No. 2 2007

African Journals Online (AJOL)

ROP4

(having been in operation for at least five years). ... rights of the child, the children were weighed in light clothing rather than in the nude. ..... 13. Volume 7 No. 2 2007. Table 1: Mean Z-scores by Area, Type of Farming, Income Level, Sex of ...

Ice-nucleating particle concentrations unaffected by urban air pollution in Beijing, China

Science.gov (United States)

Chen, Jie; Wu, Zhijun; Augustin-Bauditz, Stefanie; Grawe, Sarah; Hartmann, Markus; Pei, Xiangyu; Liu, Zirui; Ji, Dongsheng; Wex, Heike

2018-03-01

Exceedingly high levels of PM2.5 with complex chemical composition occur frequently in China. It has been speculated whether anthropogenic PM2.5 may significantly contribute to ice-nucleating particles (INP). However, few studies have focused on the ice-nucleating properties of urban particles. In this work, two ice-nucleating droplet arrays have been used to determine the atmospheric number concentration of INP (NINP) in the range from -6 to -25 °C in Beijing. No correlations between NINP and either PM2.5 or black carbon mass concentrations were found, although both varied by more than a factor of 30 during the sampling period. Similarly, there were no correlations between NINP and either total particle number concentration or number concentrations for particles with diameters > 500 nm. Furthermore, there was no clear difference between day and night samples. All these results indicate that Beijing air pollution did not increase or decrease INP concentrations in the examined temperature range above values observed in nonurban areas; hence, the background INP concentrations might not be anthropogenically influenced as far as urban air pollution is concerned, at least in the examined temperature range.

Aerosol composition of urban plumes passing over a rural monitoring site

International Nuclear Information System (INIS)

Ellestad, T.G.

1980-01-01

A field study conducted at a ground site 100 km north of St. Louis, Mo., to measure the aerosol composition and gaseous concentrations of urban plumes passing the site is discussed. Coarse and fine aerosol elemental concentrations, height scattering, meteorological data and concentrations of SO 2 , CO, O 3 , and NO-NO/sub x/ were measured and then analyzed together with data from associate investigators on fluorocarbon-11, total hydrocarbons, and size distributions. The results show that: (1) gaseous and elemental aerosol concentrations at the ground site 100 km from the St. Louis urban area were clearly influenced by the St. Louis urban plume, (2) the urban plumes of Chicago and Indianapolis, 350 km from the ground site, may have been detected, (3) sulfur compounds, presumably sulfates, accounted for 30-40% of the mass loading within the St. Louis urban plume, and resided almost entirely within the size range below 2.5 microns, (4) the most reliable urban-plume tracers in this study were fine Pb, fluorocarbon-11, total nonmethane hydrocarbons, and CO, and (5) over a period of several days, there may have been a regional buildup of fine S, light scattering, aerosol mass, O 3 , and NO/sub x/ and, to a lesser extent, CO and fluorocarbon-11

Urban flood simulation based on the SWMM model

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L. Jiang

2015-05-01

Full Text Available China is the nation with the fastest urbanization in the past decades which has caused serious urban flooding. Flood forecasting is regarded as one of the important flood mitigation methods, and is widely used in catchment flood mitigation, but is not widely used in urban flooding mitigation. This paper, employing the SWMM model, one of the widely used urban flood planning and management models, simulates the urban flooding of Dongguan City in the rapidly urbanized southern China. SWMM is first set up based on the DEM, digital map and underground pipeline network, then parameters are derived based on the properties of the subcatchment and the storm sewer conduits; the parameter sensitivity analysis shows the parameter robustness. The simulated results show that with the 1-year return period precipitation, the studied area will have no flooding, but for the 2-, 5-, 10- and 20-year return period precipitation, the studied area will be inundated. The results show the SWMM model is promising for urban flood forecasting, but as it has no surface runoff routing, the urban flooding could not be forecast precisely.

Area-level risk factors for adverse birth outcomes: trends in urban and rural settings

OpenAIRE

Kent, Shia T; McClure, Leslie A; Zaitchik, Ben F; Gohlke, Julia M

2013-01-01

Background Significant and persistent racial and income disparities in birth outcomes exist in the US. The analyses in this manuscript examine whether adverse birth outcome time trends and associations between area-level variables and adverse birth outcomes differ by urban?rural status. Methods Alabama births records were merged with ZIP code-level census measures of race, poverty, and rurality. B-splines were used to determine long-term preterm birth (PTB) and low birth weight (LBW) trends b...

A steady-state continuous flow chamber for the study of daytime and nighttime chemistry under atmospherically relevant NO levels

Science.gov (United States)

Zhang, Xuan; Ortega, John; Huang, Yuanlong; Shertz, Stephen; Tyndall, Geoffrey S.; Orlando, John J.

2018-05-01

Experiments performed in laboratory chambers have contributed significantly to the understanding of the fundamental kinetics and mechanisms of the chemical reactions occurring in the atmosphere. Two chemical regimes, classified as high-NO vs. zero-NO conditions, have been extensively studied in previous chamber experiments. Results derived from these two chemical scenarios are widely parameterized in chemical transport models to represent key atmospheric processes in urban and pristine environments. As the anthropogenic NOx emissions in the United States have decreased remarkably in the past few decades, the classic high-NO and zero-NO conditions are no longer applicable to many regions that are constantly impacted by both polluted and background air masses. We present here the development and characterization of the NCAR Atmospheric Simulation Chamber, which is operated in steady-state continuous flow mode for the study of atmospheric chemistry under intermediate NO conditions. This particular chemical regime is characterized by constant sub-ppb levels of NO and can be created in the chamber by precise control of the inflow NO concentration and the ratio of chamber mixing to residence timescales. Over the range of conditions achievable in the chamber, the lifetime of peroxy radicals (RO2), a key intermediate from the atmospheric degradation of volatile organic compounds (VOCs), can be extended to several minutes, and a diverse array of reaction pathways, including unimolecular pathways and bimolecular reactions with NO and HO2, can thus be explored. Characterization experiments under photolytic and dark conditions were performed and, in conjunction with model predictions, provide a basis for interpretation of prevailing atmospheric processes in environments with intertwined biogenic and anthropogenic activities. We demonstrate the proof of concept of the steady-state continuous flow chamber operation through measurements of major first-generation products

A steady-state continuous flow chamber for the study of daytime and nighttime chemistry under atmospherically relevant NO levels

Directory of Open Access Journals (Sweden)

X. Zhang

2018-05-01

Full Text Available Experiments performed in laboratory chambers have contributed significantly to the understanding of the fundamental kinetics and mechanisms of the chemical reactions occurring in the atmosphere. Two chemical regimes, classified as high-NO vs. zero-NO conditions, have been extensively studied in previous chamber experiments. Results derived from these two chemical scenarios are widely parameterized in chemical transport models to represent key atmospheric processes in urban and pristine environments. As the anthropogenic NOx emissions in the United States have decreased remarkably in the past few decades, the classic high-NO and zero-NO conditions are no longer applicable to many regions that are constantly impacted by both polluted and background air masses. We present here the development and characterization of the NCAR Atmospheric Simulation Chamber, which is operated in steady-state continuous flow mode for the study of atmospheric chemistry under intermediate NO conditions. This particular chemical regime is characterized by constant sub-ppb levels of NO and can be created in the chamber by precise control of the inflow NO concentration and the ratio of chamber mixing to residence timescales. Over the range of conditions achievable in the chamber, the lifetime of peroxy radicals (RO2, a key intermediate from the atmospheric degradation of volatile organic compounds (VOCs, can be extended to several minutes, and a diverse array of reaction pathways, including unimolecular pathways and bimolecular reactions with NO and HO2, can thus be explored. Characterization experiments under photolytic and dark conditions were performed and, in conjunction with model predictions, provide a basis for interpretation of prevailing atmospheric processes in environments with intertwined biogenic and anthropogenic activities. We demonstrate the proof of concept of the steady-state continuous flow chamber operation through measurements of major first

NO{sub 2} and CO nonattainment areas: a pragmatic approach to source reduction assessment

Energy Technology Data Exchange (ETDEWEB)

Cernuschi, S.; Giugliano, M.; Marzolo, F. [D.I.I.A.R. - Politecnico di Milano, Milan (Italy). Environmental Section

1995-12-31

Many Italian large conurbations have CO and NO{sub 2} air quality standards exceeded and, consequently, require control enforcement plans to attain and maintain regulations not respected. In planning the interventions to be undertaken a fundamental issue is represented by the relationships between active emission sources and air quality, commonly described through mathematical models for evaluating the expected effects of the different reduction scenarios. This approach, relatively feasible for slightly or non reactive pollutants like CO, becomes not as easy to be applied for secondary pollutants, like NO{sub 2}, mainly for the complex photo chemical reaction systems involved in their atmospheric presence and the consequent modeling difficulties related either to the description of the system itself than to the detail in input data required. A practicable alternative in this framework relies in the utilization of statistical models for deriving, through the empirical description of the relationships between the parameters of interest, the reduction levels required for complying with the standards. Following an approach already applied with useful results to the same area, present work reports on the development and application to Milan urban area of statistical models for describing the relationships between CO and NO{sub x} annual concentration averages and the corresponding air quality standard parameters (number of standard exceedances for CO and 98th percentile of hourly concentrations for NO{sub 2}). The models are utilised upstream to simple roll-back models for the assessment of the reduction in emissions strength required for attaining air quality standards for the area. (author)

NO{sub 2} and CO nonattainment areas: a pragmatic approach to source reduction assessment

Energy Technology Data Exchange (ETDEWEB)

Cernuschi, S; Giugliano, M; Marzolo, F [D.I.I.A.R. - Politecnico di Milano, Milan (Italy). Environmental Section

1996-12-31

Many Italian large conurbations have CO and NO{sub 2} air quality standards exceeded and, consequently, require control enforcement plans to attain and maintain regulations not respected. In planning the interventions to be undertaken a fundamental issue is represented by the relationships between active emission sources and air quality, commonly described through mathematical models for evaluating the expected effects of the different reduction scenarios. This approach, relatively feasible for slightly or non reactive pollutants like CO, becomes not as easy to be applied for secondary pollutants, like NO{sub 2}, mainly for the complex photo chemical reaction systems involved in their atmospheric presence and the consequent modeling difficulties related either to the description of the system itself than to the detail in input data required. A practicable alternative in this framework relies in the utilization of statistical models for deriving, through the empirical description of the relationships between the parameters of interest, the reduction levels required for complying with the standards. Following an approach already applied with useful results to the same area, present work reports on the development and application to Milan urban area of statistical models for describing the relationships between CO and NO{sub x} annual concentration averages and the corresponding air quality standard parameters (number of standard exceedances for CO and 98th percentile of hourly concentrations for NO{sub 2}). The models are utilised upstream to simple roll-back models for the assessment of the reduction in emissions strength required for attaining air quality standards for the area. (author)

The Use of Principal Component Analysis for Source Identification of PM2.5 from Selected Urban and Regional Background Sites in Poland

Science.gov (United States)

Błaszczak, Barbara

2018-01-01

The paper reports the results of the measurements of water-soluble ions and carbonaceous matter content in the fine particulate matter (PM2.5), as well as the contributions of major sources in PM2.5. Daily PM2.5 samples were collected during heating and non-heating season of the year 2013 in three different locations in Poland: Szczecin (urban background), Trzebinia (urban background) and Złoty Potok (regional background). The concentrations of PM2.5, and its related components, exhibited clear spatiotemporal variability with higher levels during the heating period. The share of the total carbon (TC) in PM2.5 exceeded 40% and was primarily determined by fluctuations in the share of OC. Sulfates (SO42-), nitrates (NO3-) and ammonium (NH4+) dominated in the ionic composition of PM2.5 and accounted together 34% (Szczecin), 30% (Trzebinia) and 18% (Złoty Potok) of PM2.5 mass. Source apportionment analysis, performed by PCA-MLRA model (Principal Component Analysis - Multilinear Regression Analysis), revealed that secondary aerosol, whose presence is related to oxidation of gaseous precursors emitted from fuel combustion and biomass burning, had the largest contribution in observed PM2.5 concentrations. In addition, the contribution of traffic sources together with road dust resuspension, was observed. The share of natural sources (sea spray, crustal dust) was generally lower.

The Use of Principal Component Analysis for Source Identification of PM2.5 from Selected Urban and Regional Background Sites in Poland

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Błaszczak Barbara

2018-01-01

Full Text Available The paper reports the results of the measurements of water-soluble ions and carbonaceous matter content in the fine particulate matter (PM2.5, as well as the contributions of major sources in PM2.5. Daily PM2.5 samples were collected during heating and non-heating season of the year 2013 in three different locations in Poland: Szczecin (urban background, Trzebinia (urban background and Złoty Potok (regional background. The concentrations of PM2.5, and its related components, exhibited clear spatiotemporal variability with higher levels during the heating period. The share of the total carbon (TC in PM2.5 exceeded 40% and was primarily determined by fluctuations in the share of OC. Sulfates (SO42-, nitrates (NO3- and ammonium (NH4+ dominated in the ionic composition of PM2.5 and accounted together ~34% (Szczecin, ~30% (Trzebinia and ~18% (Złoty Potok of PM2.5 mass. Source apportionment analysis, performed by PCA-MLRA model (Principal Component Analysis – Multilinear Regression Analysis, revealed that secondary aerosol, whose presence is related to oxidation of gaseous precursors emitted from fuel combustion and biomass burning, had the largest contribution in observed PM2.5 concentrations. In addition, the contribution of traffic sources together with road dust resuspension, was observed. The share of natural sources (sea spray, crustal dust was generally lower.

Trends in Urbanization and Implications for Peri-Urban Livelihoods in Accra, Ghana

Science.gov (United States)

Adom, Cynthia

Urbanization is a common occurrence in both developed and developing worlds. Similar to occurrences in other developing world cities, Accra's urbanization is marked by fast, unplanned and uneven growth into mostly peripheral lands (Grant and Yankson 2002; Yeboah 2001; Ghana Statistical Service (GSS) 2002). Such trends in urbanization in places where data on the urbanization process is seriously inadequate and infrequent, (Rakodi 1997a; Ohadika 1991; Fasona and Omojola 2004) pose a major challenge to urban planning and management (Henderson 2002), and affect the livelihood base of several peri-urban households. Properly monitoring the urbanization process in the developing world and understanding its effects on people's lives depends on the availability of useful and up-to- date data (Weber and Puissant 2003; Mundia and Aniya 2006) that could be obtained using new and robust analytical techniques (Yang 2003). In addition, in the urban environment, differences in rates of urbanization, income, employment status, and gender dynamics across neighborhoods suggest that the impacts of increasing urbanization on peri-urban livelihoods are likely to vary across peoples and places. Against this backdrop, this dissertation uses Accra as a case study to, first, measures the nature and extent of urban expansion using a non-conventional technique, and then analyzes neighborhood - and gender-differentiated impacts of increasing urbanization on household livelihoods in peri-urban Accra. Study findings reveal: 1) major conversion of vegetated land to urban lands uses and support the effectiveness of the Self-Organizing Map and Landsat data to map complex and hazy urban tropical environments; 2) that the impacts of urbanization on peri-urban livelihoods are structured along the lines of neighborhood-level urbanization; changes brought by a higher rate of urbanization are more beneficial than harmful to household livelihoods; 3) that positive livelihood outcomes in high

Limitations of ozone data assimilation with adjustment of NOx emissions: mixed effects on NO2 forecasts over Beijing and surrounding areas

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X. Tang

2016-05-01

Full Text Available This study investigates a cross-variable ozone data assimilation (DA method based on an ensemble Kalman filter (EnKF that has been used in the companion study to improve ozone forecasts over Beijing and surrounding areas. The main purpose is to delve into the impacts of the cross-variable adjustment of nitrogen oxide (NOx emissions on the nitrogen dioxide (NO2 forecasts over this region during the 2008 Beijing Olympic Games. A mixed effect on the NO2 forecasts was observed through application of the cross-variable assimilation approach in the real-data assimilation (RDA experiments. The method improved the NO2 forecasts over almost half of the urban sites with reductions of the root mean square errors (RMSEs by 15–36 % in contrast to big increases of the RMSEs over other urban stations by 56–239 %. Over the urban stations with negative DA impacts, improvement of the NO2 forecasts (with 7 % reduction of the RMSEs was noticed at night and in the morning versus significant deterioration during daytime (with 190 % increase of the RMSEs, suggesting that the negative data assimilation impacts mainly occurred during daytime. Ideal-data assimilation (IDA experiments with a box model and the same cross-variable assimilation method confirmed the mixed effects found in the RDA experiments. In the same way, NOx emission estimation was improved at night and in the morning even under large biases in the prior emission, while it deteriorated during daytime (except for the case of minor errors in the prior emission. The mixed effects observed in the cross-variable data assimilation, i.e., positive data assimilation impacts on NO2 forecasts over some urban sites, negative data assimilation impacts over the other urban sites, and weak data assimilation impacts over suburban sites, highlighted the limitations of the EnKF under strong nonlinear relationships between chemical variables. Under strong nonlinearity between daytime ozone concentrations and

Elevated Immune Gene Expression Is Associated with Poor Reproductive Success of Urban Blue Tits

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Pablo Capilla-Lasheras

2017-06-01

Full Text Available Urban and forest habitats differ in many aspects that can lead to modifications of the immune system of wild animals. Altered parasite communities, pollution, and artificial light at night in cities have been associated with exacerbated inflammatory responses, with possibly negative fitness consequences, but few data are available from free-living animals. Here, we investigate how urbanization affects major immune pathways and experimentally test potentially contributing factors in blue tits (Cyanistes caeruleus from an urban and forest site. We first compared breeding adults by quantifying the mRNA transcript levels of proteins associated with anti-bacterial, anti-malarial (TLR4, LY86 and anti-helminthic (Type 2 transcription factor GATA3 immune responses. Adult urban and forest blue tits differed in gene expression, with significantly increased TLR4 and GATA3, but not LY86, in the city. We then experimentally tested whether these differences were environmentally induced by cross-fostering eggs between the sites and measuring mRNA transcripts in nestlings. The populations differed in reduced reproductive success, with a lower fledging success and lower fledgling weight recorded at the urban site. This mirrors the findings of our twin study reporting that the urban site was severely resource limited when compared to the forest. Because of low urban survival, robust gene expression data were only obtained from nestlings reared in the forest. Transcript levels in these nestlings showed no (TLR4, LY86, or weak (GATA3, differences according to their origin from forest or city nests, suggesting little genetic or maternal contribution to nestling immune transcript levels. Lastly, to investigate differences in parasite pressure between urban and forest sites, we measured the prevalence of malaria in adult and nestling blood. Prevalence was invariably high across environments and not associated with the transcript levels of the studied immune genes. Our

Reassessment of urbanization effect on surface air temperature trends at an urban station of North China

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Bian, Tao; Ren, Guoyu

2017-11-01

Based on a homogenized data set of monthly mean temperature, minimum temperature, and maximum temperature at Shijiazhuang City Meteorological Station (Shijiazhuang station) and four rural meteorological stations selected applying a more sophisticated methodology, we reanalyzed the urbanization effects on annual, seasonal, and monthly mean surface air temperature (SAT) trends for updated time period 1960-2012 at the typical urban station in North China. The results showed that (1) urbanization effects on the long-term trends of annual mean SAT, minimum SAT, and diurnal temperature range (DTR) in the last 53 years reached 0.25, 0.47, and - 0.50 °C/decade, respectively, all statistically significant at the 0.001 confidence level, with the contributions from urbanization effects to the overall long-term trends reaching 67.8, 78.6, and 100%, respectively; (2) the urbanization effects on the trends of seasonal mean SAT, minimum SAT, and DTR were also large and statistically highly significant. Except for November and December, the urbanization effects on monthly mean SAT, minimum SAT, and DTR were also all statistically significant at the 0.05 confidence level; and (3) the annual, seasonal, and monthly mean maximum SAT series at the urban station registered a generally weaker and non-significant urbanization effect. The updated analysis evidenced that our previous work for this same urban station had underestimated the urbanization effect and its contribution to the overall changes in the SAT series. Many similar urban stations were being included in the current national and regional SAT data sets, and the results of this paper further indicated the importance and urgency for paying more attention to the urbanization bias in the monitoring and detection of global and regional SAT change based on the data sets.

Modeling the intraurban variation in nitrogen dioxide in urban areas in Kathmandu Valley, Nepal.

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Gurung, Anobha; Levy, Jonathan I; Bell, Michelle L

2017-05-01

With growing urbanization, traffic has become one of the main sources of air pollution in Nepal. Understanding the impact of air pollution on health requires estimation of exposure. Land use regression (LUR) modeling is widely used to investigate intraurban variation in air pollution for Western cities, but LUR models are relatively scarce in developing countries. In this study, we developed LUR models to characterize intraurban variation of nitrogen dioxide (NO 2 ) in urban areas of Kathmandu Valley, Nepal, one of the fastest urbanizing areas in South Asia. Over the study area, 135 monitoring sites were selected using stratified random sampling based on building density and road density along with purposeful sampling. In 2014, four sampling campaigns were performed, one per season, for two weeks each. NO 2 was measured using duplicate Palmes tubes at 135 sites, with additional information on nitric oxide (NO), NO 2 , and nitrogen oxide (NOx) concentrations derived from Ogawa badges at 28 sites. Geographical variables (e.g., road network, land use, built area) were used as predictor variables in LUR modeling, considering buffers 25-400m around each monitoring site. Annual average NO 2 by site ranged from 5.7 to 120ppb for the study area, with higher concentrations in the Village Development Committees (VDCs) of Kathmandu and Lalitpur than in Kirtipur, Thimi, and Bhaktapur, and with variability present within each VDC. In the final LUR model, length of major road, built area, and industrial area were positively associated with NO 2 concentration while normalized difference vegetation index (NDVI) was negatively associated with NO 2 concentration (R 2 =0.51). Cross-validation of the results confirmed the reliability of the model. The combination of passive NO 2 sampling and LUR modeling techniques allowed for characterization of nitrogen dioxide patterns in a developing country setting, demonstrating spatial variability and high pollution levels. Copyright © 2017

Fiscal 1998 research report. Study on the possibility of international cooperation for high- efficiency urban heat use systems for CO{sub 2} reduction; 1998 nendo chosa hokokusho. CO{sub 2} sakugen no tame no toshi netsu riyo system kokoritsuka ni kakawaru kokusai kyoryoku kanosei chosa hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

This research aims at study on the possibility of international cooperation such as technology transfer and technical cooperation between developed countries for introduction of high-efficiency urban heat use systems into developing countries from the viewpoint of global warming control. On the case of a city in the south-eastern district in China, this research studies the principle of international cooperation such as technology transfer and research cooperation through survey on social and economical restrictions to their introduction into developing countries and study on a CO{sub 2} reduction effect by the introduction. This report describes the current technology for high-efficiency urban heat use systems in developed countries, the current energy use in Chinese cities and some issues, current heat use technologies, the case study on the potential and constraint of high- efficiency urban heat use systems, and the case study on the CO{sub 2} reduction effect of the high-efficiency urban heat use system. Expectation for Japanese technical cooperation as such international cooperation is described. (NEDO)

The role of urban forest to reduce rain acid in urban industrial areas

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Slamet, B.; Agustiarni, Y.; Hidayati; Basyuni, M.

2018-03-01

Urban forest has many functions mainly on improving the quality of the urban environment. One of the functions is to increase pH and reduce dangerous chemical content. The aim of the research is to find out the role of vegetation density of urban forest around the industrial area in reducing the acid rain. The condition of land cover was classified into four classes which are dense, medium, sparse and open area. The water of the throughfall and stemflow was taken from each type of land cover except in the open area. Parameters measured in this study are water acidity (pH), anion content (SO4 2- and NO3 -), cation content (Ca2+, Mg2+, and NH4 +) and electrical conductivity (EC). The results indicated that urban forest vegetation was able to increase the pH of rain water from 5.42 which is in an open area without vegetation to be 7.13 and 7.32 in dense and moderate vegetation cover by throughfall mechanism, respectively. Rain water acidity also decreased through stemflow mechanism with a pH ranged from 5.92 - 6.43. Urban forest vegetation decreased sulfate content (SO42-) from 528.67 mg/l in open area to 44 - 118 mg/l by throughfall mechanism and ranged from 90 to 366.67 mg/l through stemflow mechanism. Urban forest vegetation significantly decreased the rainwater nitrate content from 27 mg/l to 0.03 - 0.70 mg/l through the mechanism of throughfall and between 1.53 - 8.82 mg/l through the stemflow mechanism. Urban forest vegetation also increased the concentration of cations (NH4+, Ca2+, Mg2+, Na+) compared with open areas. Urban forest vegetation showed increased the electrical conductivity (EC) from 208.12 μmhos/cm to 344.67 - 902.17 μmhos/cm through the through fall mechanism and 937.67 - 1058.70 μmhos/cm through the stemflow mechanism. The study suggested that urban forests play a significant role in reducing rainwater acidity and improving the quality of rainwater that reached the soil surface.

A Model for Assessing the Level of Walkability in Urban Neighborhoods in Sri Lanka

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Gayani Ranasinghe

2015-11-01

Full Text Available The quality of the neighboring environment plays a major role in encouraging people to walk when attending their daily needs. Although past studies have identified a relationship between neighborhood design factors and the level of walkability, this interdependence is poorly understood in urban planning in Sri Lanka. The purpose of this study is to determine factors and conditions that influence walkability in a selected neighborhood in the town of Panadura and develop a model to predict what design factors enhance walkability in the neighborhood area. Ninety three (93 factors that affect the walkability in urban neighborhood were identified as the findings of the literature review of this study. Seventy six (76 walkability factors identified through perception surveys were examined within a 100m radius of 70 buffered circles representing 140 participants’ residences through a questionnaire survey and field observations. Chi-square and Bivariate correlation analysis were carried out to identify the most decisive factors for walkability. Multiple Linear Regression analysis was applied to develop a model to assess the level of walkability of residents in the selected area based on the most significant factors. The study has identified main nine variables that determine the level of walkability. Based on the significant values the model can be used to assess the level of walkability of the people in Sri Lankan context.

Wet nitrogen deposition across the urban-intensive agricultural-rural transect of a small urban area in southwest China.

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Deng, Ouping; Zhang, Shirong; Deng, Liangji; Zhang, Chunlong; Fei, Jianbo

2018-03-01

Understanding of the spatial and temporal variation of the flux of atmospheric nitrogen (N) deposition is essential for assessment of its impact on ecosystems. However, little attention has been paid to the variability of N deposition across urban-intensive agricultural-rural transects. A continuous 2-year observational study (from January 2015 to December 2016) was conducted to determine wet N deposition across the urban-intensive agricultural-rural transect of a small urban area in southwest China. Significantly spatial and temporal variations were found in the research area. Along the urban-intensive agricultural-rural transect, the TN and NH 4 + -N deposition first increased and then decreased, and the NO 3 - -N and dissolved organic N (DON) deposition decreased continuously. Wet N deposition was mainly affected by the districts of agro-facilities, roads and build up lands. Wet NH 4 + -N deposition had non-seasonal emission sources including industrial emissions and urban excretory wastes in urban districts and seasonal emission sources such as fertilizer and manure volatilization in the other districts. However, wet NO 3 - -N deposition had seasonal emission sources such as industrial emissions and fireworks in urban district and non-seasonal emission sources such as transportation in the other districts. Deposition of DON was likely to have had similar sources to NO 3 - -N deposition in rural district, and high-temperature-dependent sources in urban and intensive agricultural districts. Considering the annual wet TN deposition in the intensive agricultural district was about 11.1% of the annual N fertilizer input, N fertilizer rates of crops should be reduced in this region to avoid the excessive application, and the risk of N emissions to the environment.

Changing and Differentiated Urban Landscape in China: Spatiotemporal Patterns and Driving Forces.

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Fang, Chuanglin; Li, Guangdong; Wang, Shaojian

2016-03-01

Urban landscape spatiotemporal change patterns and their driving mechanisms in China are poorly understood at the national level. Here we used remote sensing data, landscape metrics, and a spatial econometric model to characterize the spatiotemporal patterns of urban landscape change and investigate its driving forces in China between 1990 and 2005. The results showed that the urban landscape pattern has experienced drastic changes over the past 15 years. Total urban area has expanded approximately 1.61 times, with a 2.98% annual urban-growth rate. Compared to previous single-city studies, although urban areas are expanding rapidly, the overall fragmentation of the urban landscape is decreasing and is more irregular and complex at the national level. We also found a stair-stepping, urban-landscape changing pattern among eastern, central, and western counties. In addition, administrative level, urban size, and hierarchy have effects on the urban landscape pattern. We also found that a combination of landscape metrics can be used to supplement our understanding of the pattern of urbanization. The changes in these metrics are correlated with geographical indicators, socioeconomic factors, infrastructure variables, administrative level factors, policy factors, and historical factors. Our results indicate that the top priority should be strengthening the management of urban planning. A compact and congregate urban landscape may be a good choice of pattern for urban development in China.

The influence of urban development and social mobility on socioeconomic level: The application of GIS on urban ecosystems

Science.gov (United States)

Suhaili Mansor, Nur; Zulhaidi Mohd Shafri, Helmi; Mansor, Shattri; Paradhan, Biswajeet

2014-06-01

Specifically, the integration between social sciences and natural science are fundamental in our understanding of the economic, social and technological transformations that have drastically changed the society. This study will be based on the municipality of Sungai Petani, Kedah as it has been most influenced by urbanization and urban development. Urban development in Sungai Petani is closely associated with a tremendous increase in demand for land, which is highly related to population growth, human movement and their social mobility. The qualitative case study taken will rely on the visual interpretation technique that would allow the researcher to develop a map of urban changes detection. The potential application of GIS information to estimate socioeconomic indicators and the modelling of socio-economic activities that are explored in this study is hoped to increase further our understanding of the impacts of development and urbanization on social life.

The influence of urban development and social mobility on socioeconomic level: The application of GIS on urban ecosystems

International Nuclear Information System (INIS)

Mansor, Nur Suhaili; Shafri, Helmi Zulhaidi Mohd; Mansor, Shattri; Paradhan, Biswajeet

2014-01-01

Specifically, the integration between social sciences and natural science are fundamental in our understanding of the economic, social and technological transformations that have drastically changed the society. This study will be based on the municipality of Sungai Petani, Kedah as it has been most influenced by urbanization and urban development. Urban development in Sungai Petani is closely associated with a tremendous increase in demand for land, which is highly related to population growth, human movement and their social mobility. The qualitative case study taken will rely on the visual interpretation technique that would allow the researcher to develop a map of urban changes detection. The potential application of GIS information to estimate socioeconomic indicators and the modelling of socio-economic activities that are explored in this study is hoped to increase further our understanding of the impacts of development and urbanization on social life

A meta-analysis of global urban land expansion.