WorldWideScience

Sample records for ambient ozone growth

  1. Interactive effects of ambient ozone and climate measured on growth of mature loblolly pine trees

    McLaughlin, S.B. [Oak Ridge National Lab., TN (United States). Environmental Sciences Div.; Downing, D.J. [Oak Ridge National Lab., TN (United States). Engineering Physics and Mathematics Div.

    1996-04-01

    The effects of ambient ozone on the growth of large trees were evaluated. A 6-year study was conducted at a site in eastern Tennessee where seasonal growth patterns of mature loblolly pine trees were analysed. Patterns of stem expansion and contraction of 34 trees were studied using serial measurements with dendrometer band systems. Soil moisture, soil fertility and stand density were varied. Levels of ozone, rainfall and temperature also varied. Results showed that ozone interacted with both soil moisture stress and high temperatures. It was concluded that relatively low levels of ambient ozone can significantly reduce growth of mature forest tress and interactions between ambient ozone and climate were important modifiers of future forest growth and function. 49 refs., 6 tabs., 4 figs.

  2. Interactive effects of ambient ozone and climate measured on growth of mature loblolly pine trees

    McLaughlin, S.B.; Downing, D.J.

    1995-02-01

    Analysis of the seasonal growth patterns of mature loblolly pine trees over the interval 1988-1993 has provided the first direct measurement of reductions of stem growth of large forest trees by ambient ozone. Patterns of stem expansion and contraction of 34 trees were examined in eastern Tennessee using serial measurements with sensitive dendrometer bind systems. Study sites varied in soil moisture, soil fertility, and stand density. Levels of ozone, rainfall, and temperature varied widely over the six year study interval. Regression analysis identified statistically and biologically significant influences of ozone on stem growth. Acting either individually or in interaction with high temperature and moisture stress, higher levels of ozone were associated with reduced stem expansion of individual trees within and across years. Observed responses to ozone were relatively rapid, differed widely among trees, and across years, and were significantly amplified by low soil moisture and high air temperatures. Both short term responses, clearly tied to changing stem water status, and longer term cumulative responses were identified. These data indicate that relatively low levels of ambient ozone can significantly reduce growth of mature forest trees and that interactions between ambient ozone and climate are likely to be important modifiers of future forest growth and function. Additional studies of mechanisms of short term response and inter species comparisons are clearly needed.

  3. Assessing plant response to ambient ozone: growth of young apple trees in open-top chambers and corresponding ambient air plots

    Open-top chambers (OTCs) and corresponding ambient air plots (AA) were used to assess the impact of ambient ozone on growth of newly planted apple trees at the Montague Field research center in Amherst, MA. Two-year-old apple trees (Malus domestica Borkh 'Rogers Red McIntosh') were planted in the ground in circular plots. Four of the plots were enclosed with OTCs where incoming air was charcoal-filtered (CF); four were enclosed with OTCs where incoming air was not charcoal-filtered (NF) and four were not enclosed, allowing access to ambient air conditions (AA). Conditions in both CF and NF OTCs resulted in increased tree growth and changed incidence of disease and arthropod pests, compared to trees in AA. As a result, we were not able to use the OTC method to assess the impact of ambient ozone on growth of young apple trees in Amherst, MA. - Capsule: Conditions in charcoal-filtered and non-filtered open-top chambers affected apple tree growth equally and prevented assessment of ambient ozone effects

  4. Establishing a cause and effect relationship for ambient ozone exposure and tree growth in the forest: Progress and an experimental approach

    Much has been written about the effects of ambient ozone on tree growth. Cause and effect has been established with seedlings in chambers. Results from multi-year studies with older tree seedlings, in open-top chambers, have been inconclusive, due to chamber effects. Extrapolation of results from chambers to trees in the forest is not possible. Predictive models for forest tree growth reductions caused by ozone have been developed, but not verified. Dendrochronological methods have been used to establish correlations between radial growth reductions in forest trees and ambient ozone exposure. The protective chemical ethylenediurea (EDU) has been used to protect tree seedlings from ozone injury. An experimental approach is advocated here that utilizes forest trees selected for sensitivity and non-sensitivity to ozone, dendrochronological methods, the protective chemical EDU, and monitoring data for ambient ozone, stomatal conductance, soil moisture potential, air temperature, PAR, etc. in long-term investigations to establish cause and effect relationships. - Progress is reviewed and an experimental approach is proposed to demonstrate a cause and effect relationship for ambient ozone and forest tree growth

  5. Contribution of ambient ozone to Scots pine defoliation and reduced growth in the Central European forests: A Lithuanian case study

    The study aimed to explore if changes in crown defoliation and stem growth of Scots pines (Pinus sylvestris L.) could be related to changes in ambient ozone (O3) concentration in central Europe. To meet this objective the study was performed in 3 Lithuanian national parks, close to the ICP integrated monitoring stations from which data on meteorology and pollution were provided. Contribution of peak O3 concentrations to the integrated impact of acidifying compounds and meteorological parameters on pine stem growth was found to be more significant than its contribution to the integrated impact of acidifying compounds and meteorological parameters on pine defoliation. Findings of the study provide statistical evidence that peak concentrations of ambient O3 can have a negative impact on pine tree crown defoliation and stem growth reduction under field conditions in central and northeastern Europe where the AOT40 values for forests are commonly below their phytotoxic levels. - Peak ozone concentrations is one of the key factors affecting Scots pine trees

  6. Evaluation of physiological, growth and yield responses of a tropical oil crop (Brassica campestris L. var. Kranti) under ambient ozone pollution at varying NPK levels

    A field study was conducted to evaluate the impact of ambient ozone on mustard (Brassica campestris L. var. Kranti) plants grown under recommended and 1.5 times recommended NPK doses at a rural site of India using filtered (FCs) and non-filtered open top chambers (NFCs). Ambient mean O3 concentration varied from 41.65 to 54.2 ppb during the experiment. Plants growing in FCs showed higher photosynthetic rate at both NPK levels, but higher stomatal conductance only at recommended NPK. There were improvements in growth parameters and biomass of plants in FCs as compared to NFCs at both NPK levels with higher increments at 1.5 times recommended. Seed yield and harvest index decreased significantly only at recommended NPK in NFCs. Seed quality in terms of nutrients, protein and oil contents reduced in NFCs at recommended NPK. The application of 1.5 times recommended NPK provided protection against yield loss due to ambient O3. - NPK level above recommended alleviates the adverse effects of ambient ozone on a tropical mustard cultivar

  7. Assessing the impact of ambient ozone on growth and yield of a rice (Oryza sativa L.) and a wheat (Triticum aestivum L.) cultivar grown in the Yangtze Delta, China, using three rates of application of ethylenediurea (EDU)

    Foliar applications of ethylenediurea (abbreviated as EDU) were made at 0, 150, 300 or 450 ppm to field-grown rice and wheat in the Yangtze Delta in China. Rice and wheat responded differently to ambient ozone and EDU applications. For wheat, some growth characteristics, such as yield, seed number per plant, seed set rate and harvest index, increased significantly at 300 ppm EDU treatment, while for rice no parameters measured were statistically different regarding EDU application. The reason may be that the wheat cultivar used may be more sensitive to ozone than the rice cultivar. EDU was effective in demonstrating ozone effects on the wheat cultivar, but not on the rice cultivar. Cultivar sensitivity might be an important consideration when assessing the effects of ambient ozone on plants. - Cultivar sensitivity should be considered when using protective chemical to assess the effects of ambient ozone on plants

  8. Bioindicator plants for ambient ozone in Central and Eastern Europe

    Sixteen species of native detector plants for ambient ozone have been identified for use in Central and Eastern Europe. They include the forbs Alchemilla sp., Astrantia major, Centuarea nigra, Centauria scabiosa, Impatiens parviflora, Lapsana communis, Rumex acetosa and Senecio subalpinus; the shrubs Corylus avellana, Cornus sanguinea and Sambucus racemosa; the trees Alnus incana, Pinus cembra and Sorbus aucuparia; and the vines Humulus lupulus and Parthenocissus quinquefolia. Sensitivity to ozone and symptoms have been verified under controlled exposure conditions. Under these conditions, symptom incidence, intensity and appearance often changed with time after removal from exposure chambers. Ozone sensitivity for four species: Astrantia major, Centuarea nigra, C. scabiosa and Humulus lupulus are reported here for the first time. The other 12 species have also been confirmed by others in Western Europe. It is recommended that these detector bioindicator species be used in conjunction with ozone monitors and passive samplers so that injury symptoms incidence can be used to give biological significance to monitored ambient ozone data. - Sixteen species of verified bioindicator plants for ambient ozone are available for use in Central and Eastern Europe

  9. Effects of a three-year exposure to ambient ozone on biomass allocation in poplar using ethylenediurea

    We examined the effect of ambient ozone on visible foliar injury, growth and biomass in field-grown poplar cuttings of an Oxford clone sensitive to ozone (Populus maximoviczii Henry × berolinensis Dippel) irrigated with ethylenediurea (EDU) or water for three years. EDU is used as an ozone protectant for plants. Protective effects of EDU on ozone visible injury were found. As a result, poplar trees grown under EDU treatment increased leaves, lateral branches and root density in the third year, although no significant enhancement of stem height and diameter was found. Ambient ozone (AOT40, 24.6 ppm h; diurnal hourly average, 40.3 ppb) may finally reduce carbon gain by reducing the number of branches, and thus sites for leaf formation, in ozone-sensitive poplar trees under not-limiting conditions. -- Highlights: •A fast-growing ozone-sensitive poplar clone was treated with the ozone protectant ethylenediurea (EDU) for three years. •Ambient ozone reduced allocation of biomass to leaves, roots and lateral branches. •Effects on stem length and diameter were not significant. •EDU protected from ozone visible foliar injury and reduction of biomass accumulation. -- Ozone reduced allocation of biomass to leaves, roots and lateral branches, but did not affect stem length and diameter

  10. The response of rice grain quality to ozone exposure during growth depends on ozone level and genotype

    The effects of ozone exposure during the cropping season on rice grain quality were investigated in chamber experiments employing four ozone treatments (charcoal filtered air, ambient, 2× ambient, and 2.5× ambient concentration) and six genotypes. The concentrations of protein and lipids in brown rice increased significantly in response to ozone, while starch concentration and thousand kernel mass decreased. Other parameters, including the concentrations of iron, zinc, phenolics, stickiness and geometrical traits did not exhibit significant treatment effects. Total brown rice yield, protein yield, and iron yield were negatively affected by ozone. Numerous genotypic differences occurred in the response to ozone, indicating the possibility of optimizing the grain quality in high ozone environments by breeding. It is concluded that although the concentrations of two important macronutrients, proteins and lipids, increased in ozone treated grains, the implications for human nutrition are negative due to losses in total grain, protein and iron yield. - Highlights: ► Exposure of rice plants to elevated ozone during growth led to altered grain quality. ► Protein and lipid concentration increased whereas starch concentration and thousand kernel weight decreased. ► Rice grain, protein and iron yield tended to decrease in plants exposed to high ozone. ► These effects were responsive to different ozone levels and showed genotypic differences. ► The overall effect of ozone o human nutrition is expected to be negative. - Ozone exposure during growth tends to increase the protein and lipid concentration in rice grains but decreases total grain and nutrient yields. These effects are dependent on ozone level and genotype.

  11. Association between ambient ozone and health outcomes in Prague

    Hůnová, I.; Malý, Marek; Řezáčová, J.; Braniš, M.

    2013-01-01

    Roč. 86, č. 1 (2013), s. 89-97. ISSN 0340-0131 Grant ostatní: GA MŠk(CZ) 2B08077; GA AV ČR(CZ) M100300904 Institutional research plan: CEZ:AV0Z10300504 Keywords : ambient ozone * cardiovascular diseases * hospital admissions * mortality * respiratory diseases Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 2.198, year: 2013

  12. Ambient Ozone and Emergency Department Visits for Cellulitis

    Mieczysław Szyszkowicz

    2010-11-01

    Full Text Available Objectives were to assess and estimate an association between exposure to ground-level ozone and emergency department (ED visits for cellulitis. All ED visits for cellulitis in Edmonton, Canada, in the period April 1992–March 2002 (N = 69,547 were examined. Case-crossover design was applied to estimate odds ratio (OR, and 95% confidence interval per one interquartile range (IQR increase in ozone concentration (IQR = 14.0 ppb. Delay of ED visit relating to exposure was probed using 0- to 5-day exposure lags. For all patients in the all months (January–December and lags 0 to 2 days, OR = 1.05 (1.02, 1.07. For male patients during the cold months (October-March: OR = 1.05 (1.02, 1.09 for lags 0 and 2 and OR = 1.06 (1.02, 1.10 for lag 3. For female patients in the warm months (April-September: OR = 1.12 (1.06, 1.18 for lags 1 and 2. Cellulitis developing on uncovered (more exposed skin was analyzed separately, observed effects being stronger. Cellulitis may be associated with exposure to ambient ground level ozone; the exposure may facilitate cellulitis infection and aggravate acute symptoms.

  13. Ambient ozone concentration and emergency department visits for panic attacks.

    Cho, Jaelim; Choi, Yoon Jung; Sohn, Jungwoo; Suh, Mina; Cho, Seong-Kyung; Ha, Kyoung Hwa; Kim, Changsoo; Shin, Dong Chun

    2015-03-01

    The effect of ambient air pollution on panic disorder in the general population has not yet been thoroughly elucidated, although the occurrence of panic disorder in workers exposed to organic solvents has been reported previously. We investigated the association of ambient air pollution with the risk of panic attack-related emergency department visits. Using health insurance claims, we collected data from emergency department visits for panic attacks in Seoul, Republic of Korea (2005-2009). Daily air pollutant concentrations were obtained using automatic monitoring system data. We conducted a time-series study using a generalized additive model with Poisson distribution, which included spline variables (date of visit, daily mean temperature, and relative humidity) and parametric variables (daily mean air pollutant concentration, national holiday, and day of the week). In addition to single lag models (lag1 to lag3), cumulative lag models (lag0-1 to lag0-3) were constructed using moving-average concentrations on the days leading up to the visit. The risk was expressed as relative risk (RR) per one standard deviation of each air pollutant and its 95% confidence interval (95% CI). A total of 2320 emergency department visits for panic attacks were observed during the study period. The adjusted RR of panic attack-related emergency department visits was 1.051 (95% CI, 1.014-1.090) for same-day exposure to ozone. In cumulative models, adjusted RRs were 1.068 (1.029-1.107) in lag0-2 and 1.074 (1.035-1.114) in lag0-3. The ambient ozone concentration was significantly associated with emergency department visits for panic attacks. PMID:25669697

  14. Ozone flux to vegetation and its relationship to plant response and ambient air quality standards

    Musselman, Robert C.; Massman, William J.

    The National Ambient Air Quality Standard (NAAQS) for ozone is based on occurrences of the maximum 8 h average ambient ozone concentration. However, biologists have recommended a cumulative ozone exposure parameter to protect vegetation. In this paper we propose a third alternative which uses quantifiable flux-based numerical parameters as a replacement for cumulative ambient parameters. Herein we discuss the concept of ozone flux as it relates to plant response and the NAAQS, and document information needed before a flux-based ozone NAAQS for vegetation can be implemented. Additional research is needed in techniques for determining plant uptake and in the quantification of plant defensive mechanisms to ozone. Models which include feedback mechanisms should be developed to relate ozone flux, loading, and detoxification with photosynthesis and plant productivity.

  15. Comparative analysis of seed transcriptomes of ambient ozone-fumigated 2 different rice cultivars

    Cho, Kyoungwon; Shibato, Junko; Kubo, Akihiro; Kohno, Yoshihisa; Satoh, Kouji; Kikuchi, Shoshi; Sarkar, Abhijit; Agrawal, Ganesh Kumar; Rakwal, Randeep

    2013-01-01

    High ozone (O3) concentrations not only damage plant life but also cause considerable losses in plant productivity. To screen for molecular factors usable as potential biomarkers to identify for O3-sensitive and -tolerant lines and design O3 tolerant crops, our project examines the effects of O3 on rice, using high-throughput omics approaches. In this study, we examined growth and yield parameters of 4 rice cultivars fumigated for a life-time with ambient air (mean O3: 31.4–32.7 ppb) or filte...

  16. Nocturnal stomatal conductance and ambient air quality standards for ozone

    Musselman, Robert C.; Minnick, Tamera J.

    Vegetation response to ozone depends on ozone conductance into leaves and the defensive action inside the leaf. Ozone parameters currently used for air quality standards do not incorporate conductance or defensive components. Nighttime flux has often been ignored in ozone metrics relating to plant response, since ozone concentration and conductance are considered to be minimal at night. However, ozone concentration can remain relatively high at night, particularly in mountainous areas. Although conductance is lower at night than during the day for most plants, nocturnal conductance can result in considerable ozone flux into plants. Further, plants can be more susceptible to ozone exposure at night than during the daytime, a result of lower plant defenses at night. Any ozone metric used to relate air quality to plant response should use a 24 h ozone exposure period to include the nighttime exposures. It should also incorporate plant defensive mechanisms or their surrogate.

  17. Modelling ambient ozone in an urban area using an objective model and geostatistical algorithms

    Moral, Francisco J.; Rebollo, Francisco J.; Valiente, Pablo; López, Fernando; Muñoz de la Peña, Arsenio

    2012-12-01

    Ground-level tropospheric ozone is one of the air pollutants of most concern. Ozone levels continue to exceed both target values and the long-term objectives established in EU legislation to protect human health and prevent damage to ecosystems, agricultural crops and materials. Researchers or decision-makers frequently need information about atmospheric pollution patterns in urbanized areas. The preparation of this type of information is a complex task, due to the influence of several factors and their variability over time. In this work, some results of urban ozone distribution patterns in the city of Badajoz, which is the largest (140,000 inhabitants) and most industrialized city in Extremadura region (southwest Spain) are shown. Twelve sampling campaigns, one per month, were carried out to measure ambient air ozone concentrations, during periods that were selected according to favourable conditions to ozone production, using an automatic portable analyzer. Later, to evaluate the overall ozone level at each sampling location during the time interval considered, the measured ozone data were analysed using a new methodology based on the formulation of the Rasch model. As a result, a measure of overall ozone level which consolidates the monthly ground-level ozone measurements was obtained, getting moreover information about the influence on the overall ozone level of each monthly ozone measure. Finally, overall ozone level at locations where no measurements were available was estimated with geostatistical techniques and hazard assessment maps based on the spatial distribution of ozone were also generated.

  18. Assessing the effects of ambient ozone in China on snap bean genotypes by using ethylenediurea (EDU)

    Four genotypes of snap bean (Phaseolus vulgaris L.) were selected to study the effects of ambient ozone concentration at a cropland area around Beijing by using 450 ppm of ethylenediurea (EDU) as a chemical protectant. During the growing season, the 8 h (9:00–17:00) average ozone concentration was very high, approximately 71.3 ppb, and AOT40 was 29.0 ppm.h. All genotypes showed foliar injury, but ozone-sensitive genotypes exhibited much more injury than ozone-tolerant ones. Compared with control, EDU significantly alleviated foliar injury, increased photosynthesis rate and chlorophyll a fluorescence, Vcmax and Jmax, and seed and pod weights in ozone-sensitive genotypes but not in ozone-tolerant genotypes. EDU did not significantly affect antioxidant contents in any of the genotypes. Therefore, EDU effectively protected sensitive genotypes from ambient ozone damage, while protection on ozone-tolerant genotypes was limited. EDU can be regarded as a useful tool in risk assessment of ambient ozone on food security. - Highlights: • The average O3 concentration (9–17 h) was 71 ppb from June to August in Beijing. • Four genotypes of snap bean (Phaseolus vulgaris L.) were selected. • EDU effectively protected sensitive genotypes from ambient O3 damage. • The protection of EDU on O3-tolerant genotypes was limited. • EDU can be regarded as a useful tool in risk assessment of ambient O3 on vegetation. - EDU protects sensitive snap bean genotypes from ambient O3

  19. 77 FR 51798 - First Draft Documents Related to the Review of the National Ambient Air Quality Standards for Ozone

    2012-08-27

    ... AGENCY First Draft Documents Related to the Review of the National Ambient Air Quality Standards for... of the Ozone National Ambient Air Quality Standards: First External Review Draft. The Agency is... titled, Policy Assessment for the Review of the Ozone National Ambient Air Quality Standards:...

  20. Constraining ozone-precursor responsiveness using ambient measurements

    This study develops probabilistic estimates of ozone (O3) sensitivities to precursoremissions by incorporating uncertainties in photochemical modeling and evaluating modelperformance based on ground-level observations of O3 and oxides of nitrogen (NOx).Uncertainties in model form...

  1. The Role of Ambient Ozone in Epidemiologic Studies of Heat-Related Mortality

    Reid, Colleen E.; Snowden, Jonathan M.; KONTGIS, Caitlin; Tager, Ira B.

    2012-01-01

    Background: A large and growing literature investigating the role of extreme heat on mortality has conceptualized the role of ambient ozone in various ways, sometimes treating it as a confounder, sometimes as an effect modifier, and sometimes as a co-exposure. Thus, there is a lack of consensus about the roles that temperature and ozone together play in causing mortality. Objectives: We applied directed acyclic graphs (DAGs) to the topic of heat-related mortality to graphically represent the ...

  2. Ambient ozone and emergency department visits due to lower respiratory condition

    Termeh Kousha; Brian Rowe

    2014-01-01

    Objectives: Ambient ozone (O3) exposure is associated with a variety of health conditions. The objective of this study was to examine the effect of increased daily concentrations of ozone on emergency department (ED) visits due to lower respiratory diseases (LRD), such as acute or chronic bronchitis, in Edmonton, Canada. Materials and Methods: Data concerning 10 years (1992-2002) were obtained from 5 Edmonton hospital Emergency Departments. Odds ratios (ORs) for ED visits associated with the ...

  3. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false National 8-hour primary and secondary....10 National 8-hour primary and secondary ambient air quality standards for ozone. (a) The level of the national 8-hour primary and secondary ambient air quality standards for ozone, measured by...

  4. 77 FR 30087 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards

    2012-05-21

    ... Columbia EPA Environmental Protection Agency FR Federal Register NAAQS National Ambient Air Quality... ppm NAAQS set in 1997, but is set at a more protective level. \\2\\ See 73 FR 16436; March 27, 2008. For... 6, 2010. (See 75 FR 2938; January 19, 2010.) Because of the significant uncertainty the ozone...

  5. Moderate drought did not affect the effectiveness of ethylenediurea (EDU) in protecting Populus cathayana from ambient ozone.

    Xin, Yue; Yuan, Xiangyang; Shang, Bo; Manning, William J; Yang, Aizhen; Wang, Younian; Feng, Zhaozhong

    2016-11-01

    A field study was conducted to evaluate the effects of ambient ozone (O3) on an O3-sensitive poplar (Populus cathayana) by using ethylenediurea (EDU) as a chemical protectant under two soil water treatments (well-watered (WW) and moderate drought (MD, 50-60% of WW in volumetric soil water content). EDU was applied as foliar spray at 0, 300, 450, and 600ppm. Photosynthetic parameters, pigment contents, leaf nitrogen, antioxidant capacity, growth, and biomass were measured. The 8h (9:00-17:00) average ambient O3 concentration was 71.7ppb, and AOT40 was 29.2ppmh during the experimental period (9 June to 21 September), which was high enough to cause plant injury. MD had significantly negative effects on P. cathayana, as indicated by reduced photosynthesis, growth, and biomass, and higher MDA contents. On the other hand, EDU significantly increased photosynthesis rate, chlorophyll a fluorescence, Vcmax and Jmax, photosynthetic pigments, total antioxidant capacity, tree growth and biomass accumulation, and reduced lipid peroxidation, but there was no significant interaction between EDU and drought for most parameters, indicating that EDU can efficiently protect Populus cathayana against ambient O3 and the protection was not affected by soil water contents when soil water reached moderate drought level. Among all doses, EDU at 450ppm provided maximum protection. Comparison of EDU-treated and non-treated P. cathayana could be used as a biomarker system in risk assessment of the effects of ambient O3 on forest health. PMID:27424114

  6. Impact of Climate Change on Ambient Ozone Level and Mortality in Southeastern United States

    Montserrat Fuentes

    2010-07-01

    Full Text Available There is a growing interest in quantifying the health impacts of climate change. This paper examines the risks of future ozone levels on non-accidental mortality across 19 urban communities in Southeastern United States. We present a modeling framework that integrates data from climate model outputs, historical meteorology and ozone observations, and a health surveillance database. We first modeled present-day relationships between observed maximum daily 8-hour average ozone concentrations and meteorology measured during the year 2000. Future ozone concentrations for the period 2041 to 2050 were then projected using calibrated climate model output data from the North American Regional Climate Change Assessment Program. Daily community-level mortality counts for the period 1987 to 2000 were obtained from the National Mortality, Morbidity and Air Pollution Study. Controlling for temperature, dew-point temperature, and seasonality, relative risks associated with short-term exposure to ambient ozone during the summer months were estimated using a multi-site time series design. We estimated an increase of 0.43 ppb (95% PI: 0.14–0.75 in average ozone concentration during the 2040’s compared to 2000 due to climate change alone. This corresponds to a 0.01% increase in mortality rate and 45.2 (95% PI: 3.26–87.1 premature deaths in the study communities attributable to the increase in future ozone level.

  7. Ambient ozone and bacterium Streptococcus: A link between cellulitis and pharyngitis

    Giuseppe Valacchi

    2015-08-01

    Full Text Available Objectives: Ambient air pollution, as many publications indicate, may have associations with skin condition. The aim of this study has been to examine such common relations for cellulitis and pharyngitis. The hypothesis is that ambient ground-level ozone may help bacteria to penetrate skin or throat. Material and Methods: We used the emergency department (ED visits data in Edmonton, Canada for the period from 1992 (April to 2002 (March. We retrieved all the diagnosed ED visits for cellulitis and pharyngitis. Case-crossover design was used to study potential association between ozone and those visits. Conditional logistic regression was used to estimate odds ratios (OR and their 95% confidence intervals (95% CI. Results: The results are reported for the interquartile range (IQR = 17.9 ppb for 8 h maximum ozone. Positive and statistical significant results were obtained as follows: for lags from 0 to 3 (OR = 1.07, 95% CI: 1.03–1.12, lag 2; for lags from 0 to 6 days (OR = 1.08, 95% CI: 1.03–1.12, lag 3; for lags from 0 to 4 (OR = 1.06, 95% CI: 1.03–1.09, for lag 2 and 3. Conclusions: The findings suggest the response to exposure to ambient ground-level ozone for skin and pharyngitis considered separately and jointly.

  8. US Environmental Protection Agency's ozone epidemiology research program: A strategy for assessing the effects of ambient ozone exposure upon morbidity in exposed populations

    McDonnell, W.F.; Zenick, H.; Hayes, C.G.

    1993-01-01

    The Clean Air Act Amendments of 1990 mandate a future reduction of ambient ozone levels in many areas of the country, the cost of which will be great. In order to assess the current public health burden of ambient ozone exposure and to provide information for assessment of potential health benefits of improved air quality, the Health Effects Research Laboratory of the U.S. EPA has undertaken an Ozone Epidemiology Research Program. The three questions identified as being of most immediate importance involve the relationship of short-term ambient ozone exposure to acute respiratory illness, the relationship of recurrent exposure to chronic respiratory disease, and the relationship of recurrent exposure to development of acute respiratory illness. (Copyright (c) 1993 Air and Waste Management Association.)

  9. Ozone air pollution effects on tree-ring growth,{delta}{sup 13}C, visible foliar injury and leaf gas exchange in three ozone-sensitive woody plant species

    Novak, K. [Swiss Federal Inst. for Forest, Snow and Landscape Research, Birmensdorf (Switzerland); Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Zurich (Switzerland); Saurer, M. [Paul Scherrer Inst. Villigen (Switzerland); Fuhrer, J. [Agroscope FAL Reckenholz, Swiss Federal Research Station for Agroecology and Agriculture, Zurich (Switzerland); Skelly, J.M. [Pennsylvania State Univ., University Park, PA (United States). Dept. of Plant Pathology; Krauchi, N.; Schaub, M. [Swiss Federal Inst. for Forest, Snow and Landscape Research, Birmensdorf (Switzerland)

    2007-07-15

    Species specific plant responses to tropospheric ozone pollution depend on a range of morphological, biochemical and physiological characteristics as well as environmental factors. The effects of ambient tropospheric ozone on annual tree-ring growth, {delta}{sup 13} C in the rings, leaf gas exchange and ozone-induced visible foliar injury in three ozone-sensitive woody plant species in southern Switzerland were assessed during the 2001 and 2002 growing seasons. Seedlings of Populus nigra L., Viburnum lantana L. and Fraxinus excelsior L. were exposed to charcoal-filtered air and non-filtered air in open-top chambers, and to ambient air (AA) in open plots. The objective was to determine if a relationship exists between measurable ozone-induced effects at the leaf level and subsequent changes in annual tree-ring growth and {delta} {sup 13} C signatures. The visible foliar injury, early leaf senescence and premature leaf loss in all species was attributed to the ambient ozone exposures in the region. Ozone had pronounced negative effects on net photosynthesis and stomatal conductance in all species in 2002 and in V. lantana and F. excelsior in 2001. Water-use efficiency decreased and intercellular carbon dioxide concentrations increased in all species in response to ozone in 2002 only. The width and {delta}{sup 13} C of the 2001 and 2002 growth rings were measured for all species at the end of the 2002 growing season. Significant ozone-induced effects at the leaf level did not correspond to reduced tree-ring growth or increased {delta}{sup 13} C in all species, suggesting that the timing of ozone exposure and extent of leaf-level responses may be relevant in determining the sensitivity of tree productivity to ozone exposure. 48 refs., 4 tabs., 2 figs.

  10. Pulmonary Epithelial Integrity in Children: Relationship to Ambient Ozone Exposure and Swimming Pool Attendance

    Lagerkvist, Birgitta Json; Bernard, Alfred; Blomberg, Anders; Bergstrom, Erik; Forsberg, Bertil; Holmstrom, Karin; Karp, Kjell; Lundstrom, Nils-Goran; Segerstedt, Bo; Svensson, Mona; Nordberg, Gunnar

    2004-01-01

    Airway irritants such as ozone are known to impair lung function and induce airway inflammation. Clara cell protein (CC16) is a small anti-inflammatory protein secreted by the nonciliated bronchiolar Clara cells. CC16 in serum has been proposed as a noninvasive and sensitive marker of lung epithelial injury. In this study, we used lung function and serum CC16 concentration to examine the pulmonary responses to ambient O3 exposure and swimming pool attendance. The measurements were made on 57 ...

  11. Simulation of ozone depletion using ambient irradiance supplemented with UV lamps.

    Díaz, S; Camilión, C; Escobar, J; Deferrari, G; Roy, S; Lacoste, K; Demers, S; Belzile, C; Ferreyra, G; Gianesella, S; Gosselin, M; Nozais, C; Pelletier, E; Schloss, I; Vernet, M

    2006-01-01

    In studies of the biological effects of UV radiation, ozone depletion can be mimicked by performing the study under ambient conditions and adding radiation with UV-B lamps. We evaluated this methodology at three different locations along a latitudinal gradient: Rimouski (Canada), Ubatuba (Brazil) and Ushuaia (Argentina). Experiments of the effect of potential ozone depletion on marine ecosystems were carried out in large outdoor enclosures (mesocosms). In all locations we simulated irradiances corresponding to 60% ozone depletion, which may produce a 130-1900% increase in 305 nm irradiance at noon, depending on site and season. Supplementation with a fixed percentage of ambient irradiance provides a better simulation of irradiance increase due to ozone depletion than supplementation with a fixed irradiance value, particularly near sunrise and sunset or under cloudy skies. Calculations performed for Ushuaia showed that, on very cloudy days, supplementation by the square-wave method may produce unrealistic irradiances. Differences between the spectra of the calculated supplementing irradiance and the lamp for a given site and date will be a function of the time of day and may become more or less pronounced according to the biological weighting function of the effect under study. PMID:17205620

  12. Ambient ozone and emergency department visits due to lower respiratory condition

    Termeh Kousha

    2014-02-01

    Full Text Available Objectives: Ambient ozone (O3 exposure is associated with a variety of health conditions. The objective of this study was to examine the effect of increased daily concentrations of ozone on emergency department (ED visits due to lower respiratory diseases (LRD, such as acute or chronic bronchitis, in Edmonton, Canada. Materials and Methods: Data concerning 10 years (1992-2002 were obtained from 5 Edmonton hospital Emergency Departments. Odds ratios (ORs for ED visits associated with the increased ozone levels were calculated employing a case-crossover technique with a time-stratified strategy to define controls. In the constructed conditional logistic regression models, adjustments were made for daily number of influenza ED visits and weather variables using natural splines. ORs and their 95% confidence intervals (95% CI were reported in relation to an increase in the interquartile range (IQR = 17.9 ppb of the ground-level ozone. Results: Overall, 48 252 ED visits due to LRD were identified, of which 53% were made by males. The presentations peaked in December (12% and February (11.7% and were the lowest in August (5.6%. Positive and statistically significant results were obtained for acute bronchitis: for same day (OR = 1.09, 95% CI: 1.05-1.13, lag 0 and for lag 2, lag 3-7 and 9 days; for chronic bronchitis: for lag 6, 7, and lag 9 days (OR = 1.11, 95% CI: 1.05-1.18, lag 9. For all ED visits for LRD, lag 0, lag 1, and lag 3-9 days showed positive and statistically significant associations (OR = 1.06, 95% CI: 1.03-1.09, lag 0. Conclusions: These findings support the hypothesis concerning positive associations between ozone and the ED visits due to LRD.

  13. Ameliorating effect of UV-B radiation on the response of Norway spruce and Scots pine to ambient ozone concentrations

    Elevated levels of both ozone and UV-B radiation are typical for high-altitude sites. Few studies have investigated their possible interaction on plants. This study reports interactive effects of O3 and UV-B radiation in four-year-old Norway spruce and Scots pine trees. The trees were cultivated in controlled environmental facilities under simulated climatic conditions recorded on Mt Wank, an Alpine mountain in Bavaria, and were exposed for one growing season to simulated ambient or twice-ambient ozone regimes at either near ambient or near zero UV-B radiation levels. Chlorotic mottling and yellowing of current year needles became obvious under twice-ambient O3 in both species at the onset of a high ozone episode in July. Development of chlorotic mottling in relation to accumulated ozone concentrations over a threshold of 40 nL L–1 was more pronounced with near zero rather than ambient UV-B radiation levels. In Norway spruce, photosynthetic parameters at ambient CO2 concentration, measured at the end of the experiment, were reduced in trees cultivated under twice-ambient O3, irrespective of the UV-B treatment. Effects on photosynthetic capacity and carboxylation efficiency were restricted to trees exposed to near zero levels of UV-B radiation, and twice-ambient O3. The data indicate that UV-B radiation, applied together with O3, ameliorates the detrimental effects of O3. The data also demonstrate that foliar symptoms develop more rapidly in Scots pine than in Norway spruce at higher accumulated ozone concentrations. (author)

  14. Estimating contribution of wildland fires to ambient ozone levels in National Parks in the Sierra Nevada, California

    Data from four continuous ozone and weather monitoring sites operated by the National Park Service in Sierra Nevada, California, are used to develop an ozone forecasting model and to estimate the contribution of wildland fires on ambient ozone levels. The analyses of weather and ozone data pointed to the transport of ozone precursors from the Central Valley as an important source of pollution in these National Parks. Comparisons of forecasted and observed values demonstrated that accurate forecasts of next-day hourly ozone levels may be achieved by using a time series model with historic averages, expected local weather and modeled PM values as explanatory variables. Results on fire smoke influence indicated occurrence of significant increases in average ozone levels with increasing fire activity. The overall effect on diurnal ozone values, however, was small when compared with the amount of variability attributed to sources other than fire. - We have demonstrated that it is possible to produce accurate forecasts of next-day hourly ozone levels in the Sierra Nevada, CA, during fire season.

  15. US Environmental Protection Agency's Ozone Epidemiology Research Program: A strategy for assessing the effects of ambient ozone exposure upon morbidity in exposed populations

    McDonnell, W.F.; Zenick, H.; Hayes, C.G. (Environmental Protection Agency, Research Triangle Park, NC (United States))

    1993-07-01

    The Clean Air Act Amendments of 1990 mandate a future reduction of ambient ozone levels in many areas of the country, the cost of which will be great. In order to assess the current public health burden of ambient ozone exposure and to provide information for assessment of potential health benefits of improved air quality, the Health Effects Research Laboratory of the U.S. EPA has undertaken an Ozone Epidemiology Research Program. The research strategy which will guide this scientific program is described in this paper. Criteria for selection of important research questions as well as issues which cut across all questions and study designs are discussed. In particular, this program emphasizes the study of effects which reflect morbidity in the population. The three questions identified as being of most immediate importance involve the relationship of short-term ambient ozone exposure to acute respiratory illness, the relationship of recurrent exposure to chronic respiratory disease, and the relationship of recurrent exposure to development of acute respiratory illness. Specific research approaches and initial projects to address these three questions are described.

  16. Does ozone exposure alter growth and carbon allocation of mycorrhizal plants

    Yoshida, L.C.; Gamon, J.A. (California State Univ., Los Angeles, CA (United States)); Andersen, C.P. (Environmental Protection Agency, Corvallis, OR (United States))

    1994-06-01

    Ozone is known to adversely affect plant growth. However, it is less clear how ozone affects belowground processes. This study tests the hypothesis that ozone alters growth and carbon allocation of vesicular arbuscular mycorrhizal (VAM) plants. Two ecotypes of Elymus glaucus (blue wild rye) were exposed to mycorrhizal inoculation and episodic ozone exposures simulating atmospheric conditions in the Los Angeles Basin. Preliminary results show that effects of ozone on growth were subtle. In both ecotypes, growth of aboveground biomass was not affected by ozone while root growth was decreased. In most treatments, mycorrhizal inoculation decreased growth of leaves and stems, but had no significant effect on root growth. Three-way ANOVA tests indicated interactive effects between ecotype, mycorrhiza and ozone. Further experimental work is needed to reveal the biological processes governing these responses.

  17. Tempo-Spatial Variations of Ambient Ozone-Mortality Associations in the USA: Results from the NMMAPS Data.

    Liu, Tao; Zeng, Weilin; Lin, Hualiang; Rutherford, Shannon; Xiao, Jianpeng; Li, Xing; Li, Zhihao; Qian, Zhengmin; Feng, Baixiang; Ma, Wenjun

    2016-01-01

    Although the health effects of ambient ozone have been widely assessed, their tempo-spatial variations remain unclear. We selected 20 communities (ten each from southern and northern USA) based on the US National Morbidity, Mortality, and Air Pollution Study (NMMAPS) dataset. A generalized linear model (GLM) was used to estimate the season-specific association between each 10 ppb (lag0-2 day average) increment in daily 8 h maximum ozone concentration and mortality in every community. The results showed that in the southern communities, a 10 ppb increment in ozone was linked to an increment of mortality of -0.07%, -0.17%, 0.40% and 0.27% in spring, summer, autumn and winter, respectively. For the northern communities, the excess risks (ERs) were 0.74%, 1.21%, 0.52% and -0.65% in the spring, summer, autumn and winter seasons, respectively. City-specific ozone-related mortality effects were positively related with latitude, but negatively related with seasonal average temperature in the spring, summer and autumn seasons. However, a reverse relationship was found in the winter. We concluded that there were different seasonal patterns of ozone effects on mortality between southern and northern US communities. Latitude and seasonal average temperature were identified as modifiers of the ambient ozone-related mortality risks. PMID:27571094

  18. Evaluation and Comparison of Methods for Measuring Ozone and NO2 Concentrations in Ambient Air during DISCOVER-AQ

    Ambient evaluations of the various ozone and NO2 methods were conducted during field intensive studies as part of the NASA DISCOVER-AQ project conducted during July 2011 near Baltimore, MD; January – February 2013 in the San Juaquin valley, CA; September 2013 in Houston, TX...

  19. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    2010-07-01

    ...-hour standards are codified in 40 CFR part 81. (c) EPA's authority under paragraph (b) of this section... 40 Protection of Environment 2 2010-07-01 2010-07-01 false National 1-hour primary and secondary....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  20. Ambient ozone phytotoxic potential over the Czech forests as assessed by AOT40

    Hunova I

    2012-06-01

    Full Text Available Ambient ozone (O3 represents one of the most prominent air pollution pro­blems in Europe. We present an analysis on O3 with respect to its phytotoxic potential over Czech forests between 1994 and 2008. The phytotoxic potential is estimated based on the exposure index AOT40 for forests calculated from real-time monitoring data at 24 rural sites. Our results indicate high phytotoxic potential for most of the Czech Republic (CR with considerable inter-annual and spatial variability. The highest AOT40 values were 38-39 ppm·h. The cri­tical level for forest protection (5 ppm·h was usually exceeded early in the growing season, generally in May. In years with meteorological conditions conducive to ozone formation, the critical level was exceeded by 5-7 folds as compared to years with non-conducive conditions; nevertheless, all sites consi­stently exceeded the critical level since 1994. In the extremely hot and dry year 2003, the critical level for forests was exceeded over 31 % of the Czech forested area. More research is needed to translate these exceedances into forest injury in the CR.

  1. Loblolly pine seedling growth after inoculation with plant growth-promoting rhizobacteria and ozone exposure

    Estes, B.L.; Enebak, S.A.; Chappelka, A.H. [Auburn Univ., Auburn, AL (United States). School of Forestry and Wildlife Sciences

    2004-07-01

    The conifer tree species with the greatest economic importance in south eastern United States plantations is Loblolly pine. Plantations require intensive fertilization, pesticide application, and irrigation. In these cases growth-promoting rhizobacteria are useful in pest control. While it was once thought that ozone in the troposphere was limited to urban areas, it is now known that it is transported far from its place of origin. Ozone is known to impact plant growth negatively. There have been no previous studies on whether growth-promoting rhizobacteria can decrease the negative effects of ozone. In this study seedlings of Loblolly pine were inoculated with either Bacillus subtilis (Ehrenberg) Cohn or Paenibacillus macerans (Schardinger) Ash. These were exposed to controlled amounts of ozone for 8-12 weeks. All plants showed decreased biomass and increased foliar damage compared to plants that were not exposed to ozone. B. subtilis inoculated plants showed less foliar damage than un-inoculated ones and root dimensions were increased. The use of growth-promoting rhizobacteria is not ready for large-scale commercial application in forestry, but this demonstration of the possible beneficial effects on ozone exposure warrants further investigation. 44 refs., 3 tabs., 2 figs.

  2. Photosynthesis and growth response of almond to increased atmospheric ozone partial pressures

    Uniform nursery stock of five almond cultivars [Prunus dulcis (Mill) D.A. Webb syn. P. amygdalus Batsch, cv. Butte, Carmel, Mission, Nonpareil, and Sonora] propagated on peach (P. domstica L. Batsch.) rootstock were exposed to three different atmospheric ozone (O3) partial pressures. The trees were planted in open-top fumigation chambers on 19 Apr. 1989 at the University of California Kearny Agricultural Center located in the San Joaquin Valley of California. Exposures of the trees to three atmospheric O3 partial pressures lasted from 1 June to 2 Nov. 1989. The mean 12-h [0800-2000 h Pacific Daylight Time (PDT)] O3 partial pressures measured in the open-top chambers during the experimental period were 0.038, 0.060, and 0.112 μPa Pa-1 O3 in the charcoal filtered, ambient, and ambient + O3 treatments, respectively. Leaf net CO2 assimilation, trunk cross-sectional area growth, and root, trunk, foliage, and total dry weight of Nonpareil were reduced by increased atmospheric O3 partial pressures. Mission was unaffected by O3 and Butte, Carmel, and Sonora were intermediate in their responses. Foliage of Nonpareil also abscised prematurely in the ambient and ambient + O3 treatments. The results indicate that there are almond cultivars that are sensitive to O3 exposure

  3. Trends analyses of 30 years of ambient 8 hour ozone and precursor monitoring data in the South Central U.S.: progress and challenges.

    Sather, Mark E; Cavender, Kevin

    2016-07-13

    In the last 30 years ambient ozone concentrations have notably decreased in the South Central U.S. Yet, current ambient ozone concentrations measured over the past three years 2013-2015 in this area of the U.S. are not meeting the U.S. 2015 8 hour ozone standard of 70 parts per billion (ppb). This paper provides an update on long-term trends analyses of ambient 8 hour ozone and ozone precursor monitoring data collected over the past 30 years (1986-2015) in four South Central U.S. cities, following up on two previously published reviews of 20 and 25 year trends for these cities. All four cities have benefitted from national ozone precursor controls put in place during the 1990s and 2000s involving cleaner vehicles (vehicle fleet turnover/replacement over time), cleaner fuels, cleaner gasoline and diesel engines, and improved inspection/maintenance programs for existing vehicles. Additional ozone precursor emission controls specific to each city are detailed in this paper. The controls have resulted in impressive ambient ozone and ambient ozone precursor concentration reductions in the four South Central U.S. cities over the past 30 years, including 31-70% ambient nitrogen oxides (NOx) concentration declines from historical peaks to the present, 43-72% volatile organic compound (VOC) concentration declines from historical peaks to the present, a related 45-76% VOC reactivity decline for a subset of VOC species from historical peaks to the present, and an 18-38 ppb reduction in city 8 hour ozone design value concentrations. A new challenge for each of the four South Central U.S. cities will be meeting the U.S. 2015 8 hour ozone standard of 70 ppb. PMID:27282109

  4. Growth of soybean at future tropospheric ozone concentrations decreases canopy evapotranspiration and soil water depletion

    Bernacchi, Carl J., E-mail: bernacch@illinois.edu [Global Change and Photosynthesis Research Unit, United States Department of Agriculture Agricultural Research Service, Urbana, IL 61801 (United States); Institute for Genomic Biology and Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Leakey, Andrew D.B. [Institute for Genomic Biology and Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Kimball, Bruce A. [USDA-ARS US Arid-Land Agricultural Research Center, 21881 N. Cardon Lane, Maricopa, AZ 85238 (United States); Ort, Donald R. [Global Change and Photosynthesis Research Unit, United States Department of Agriculture Agricultural Research Service, Urbana, IL 61801 (United States); Institute for Genomic Biology and Department of Plant Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

    2011-06-15

    Tropospheric ozone is increasing in many agricultural regions resulting in decreased stomatal conductance and overall biomass of sensitive crop species. These physiological effects of ozone forecast changes in evapotranspiration and thus in the terrestrial hydrological cycle, particularly in intercontinental interiors. Soybean plots were fumigated with ozone to achieve concentrations above ambient levels over five growing seasons in open-air field conditions. Mean season increases in ozone concentrations ([O{sub 3}]) varied between growing seasons from 22 to 37% above background concentrations. The objective of this experiment was to examine the effects of future [O{sub 3}] on crop ecosystem energy fluxes and water use. Elevated [O{sub 3}] caused decreases in canopy evapotranspiration resulting in decreased water use by as much as 15% in high ozone years and decreased soil water removal. In addition, ozone treatment resulted in increased sensible heat flux in all years indicative of day-time increase in canopy temperature of up to 0.7 deg. C. - Highlights: > Globally, tropospheric ozone is currently and will likely continue to increase into the future. > We examine the impact of elevated ozone on water use by soybean at the SoyFACE research facility. > High ozone grown soybean had reduced rates of evapotranspiration and higher soil moisture. > Increases in ozone have the potential to impact the hydrologic cycle where these crops are grown. - Soybean grown in elevated concentrations of ozone is shown to evapotranspire less water compared with soybean canopies grown under current atmospheric conditions.

  5. Growth of soybean at future tropospheric ozone concentrations decreases canopy evapotranspiration and soil water depletion

    Tropospheric ozone is increasing in many agricultural regions resulting in decreased stomatal conductance and overall biomass of sensitive crop species. These physiological effects of ozone forecast changes in evapotranspiration and thus in the terrestrial hydrological cycle, particularly in intercontinental interiors. Soybean plots were fumigated with ozone to achieve concentrations above ambient levels over five growing seasons in open-air field conditions. Mean season increases in ozone concentrations ([O3]) varied between growing seasons from 22 to 37% above background concentrations. The objective of this experiment was to examine the effects of future [O3] on crop ecosystem energy fluxes and water use. Elevated [O3] caused decreases in canopy evapotranspiration resulting in decreased water use by as much as 15% in high ozone years and decreased soil water removal. In addition, ozone treatment resulted in increased sensible heat flux in all years indicative of day-time increase in canopy temperature of up to 0.7 deg. C. - Highlights: → Globally, tropospheric ozone is currently and will likely continue to increase into the future. → We examine the impact of elevated ozone on water use by soybean at the SoyFACE research facility. → High ozone grown soybean had reduced rates of evapotranspiration and higher soil moisture. → Increases in ozone have the potential to impact the hydrologic cycle where these crops are grown. - Soybean grown in elevated concentrations of ozone is shown to evapotranspire less water compared with soybean canopies grown under current atmospheric conditions.

  6. Effective interface passivation of a Ge/HfO2 gate stack using ozone pre-gate treatment and ozone ambient annealing

    The physical and electrical properties of a Ge/GeO2/HfO2/Al gate stack are investigated. A thin interfacial GeO2 layer (∼1 nm) is formed between Ge and HfO2 by dual ozone treatments, which passivates the Ge/high-k interface. Capacitors on p-type Ge substrates show very promising capacitance-voltage (C—V) characteristics by using in situ pre-gate ozone passivation and ozone ambient annealing after high-k deposition, indicating efficient passivation of the Ge/HfO2 interface. It is shown that the mid-gap interface state density atthe Ge/GeO2 interface is 6.4 × 1011 cm−2 · eV−1. In addition, the gate leakage current density of the Ge/GeO2/HfO2/Al gate stack passivated by the dual ozone treatments is reduced by about three orders of magnitude compared to that of a Ge/HfO2/Al gate stack without interface passivation. (semiconductor technology)

  7. Effective interface passivation of a Ge/HfO2 gate stack using ozone pre-gate treatment and ozone ambient annealing

    Zhao Mei; Liang Renrong; Wang Jing; Xu Jun

    2013-01-01

    The physical and electrical properties ofa Ge/GeO2/HfO2/A1 gate stack are investigated.A thin interfacial GeO2 layer (~ 1 nm) is formed between Ge and HfO2 by dual ozone treatments,which passivates the Ge/high-k interface.Capacitors on p-type Ge substrates show very promising capacitance-voltage (C-V) characteristics by using in situ pre-gate ozone passivation and ozone ambient annealing after high-k deposition,indicating efficient passivation of the Ge/HfO2 interface.It is shown that the mid-gap interface state density at the Ge/GeO2 interface is 6.4 × 101 1 cm-2.eV-1.In addition,the gate leakage current density of the Ge/GeO2/HfO2/Al gate stack passivated by the dual ozone treatments is reduced by about three orders of magnitude compared to that ofa Ge/HfO2/Al gate stack without interface passivation.

  8. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    2010-07-01

    ... waiver of the ozone monitoring requirement would be handled under provisions of 40 CFR, part 58. Some... year unless the appropriate Regional Administrator has granted a waiver under the provisions of 40 CFR... and Secondary National Ambient Air Quality Standards for Ozone H Appendix H to Part 50 Protection...

  9. Growth of soybean at future tropospheric ozone concentrations decreases canopy evapotranspiration and soil water depletion.

    Bernacchi, Carl J; Leakey, Andrew D B; Kimball, Bruce A; Ort, Donald R

    2011-06-01

    Tropospheric ozone is increasing in many agricultural regions resulting in decreased stomatal conductance and overall biomass of sensitive crop species. These physiological effects of ozone forecast changes in evapotranspiration and thus in the terrestrial hydrological cycle, particularly in intercontinental interiors. Soybean plots were fumigated with ozone to achieve concentrations above ambient levels over five growing seasons in open-air field conditions. Mean season increases in ozone concentrations ([O₃]) varied between growing seasons from 22 to 37% above background concentrations. The objective of this experiment was to examine the effects of future [O₃] on crop ecosystem energy fluxes and water use. Elevated [O₃] caused decreases in canopy evapotranspiration resulting in decreased water use by as much as 15% in high ozone years and decreased soil water removal. In addition, ozone treatment resulted in increased sensible heat flux in all years indicative of day-time increase in canopy temperature of up to 0.7 °C. PMID:21477906

  10. Ozone generation in a kHz-pulsed He-O2 capillary dielectric barrier discharge operated in ambient air

    Sands, Brian L.; Ganguly, Biswa N.

    2013-12-01

    The generation of reactive oxygen species using nonequilibrium atmospheric pressure plasma jet devices has been a subject of recent interest due to their ability to generate localized concentrations from a compact source. To date, such studies with plasma jet devices have primarily utilized radio-frequency excitation. In this work, we characterize ozone generation in a kHz-pulsed capillary dielectric barrier discharge configuration comprised of an active discharge plasma jet operating in ambient air that is externally grounded. The plasma jet flow gas was composed of helium with an admixture of up to 5% oxygen. A unipolar voltage pulse train with a 20 ns pulse risetime was used to drive the discharge at repetition rates between 2-25 kHz. Using UVLED absorption spectroscopy centered at 255 nm near the Hartley-band absorption peak, ozone was detected over 1 cm from the capillary axis. We observed roughly linear scaling of ozone production with increasing pulse repetition rate up to a "turnover frequency," beyond which ozone production steadily dropped and discharge current and 777 nm O(5P→5S°) emission sharply increased. The turnover in ozone production occurred at higher pulse frequencies with increasing flow rate and decreasing applied voltage with a common energy density of 55 mJ/cm3 supplied to the discharge. The limiting energy density and peak ozone production both increased with increasing O2 admixture. The power dissipated in the discharge was obtained from circuit current and voltage measurements using a modified parallel plate dielectric barrier discharge circuit model and the volume-averaged ozone concentration was derived from a 2D ozone absorption measurement. From these measurements, the volume-averaged efficiency of ozone production was calculated to be 23 g/kWh at conditions for peak ozone production of 41 mg/h at 11 kV applied voltage, 3% O2, 2 l/min flow rate, and 13 kHz pulse repetition rate, with 1.79 W dissipated in the discharge.

  11. Responses of a tropical tree species to ozone: visible leaf injury, growth, and lipid peroxidation.

    Cassimiro, Jéssica C; Moraes, Regina M

    2016-04-01

    The Brazilian native tree species Astronium graveolens was indicated as sensitive to ozone in a fumigation experiment. Thus, the objective of this study was to evaluate how sensitive A. graveolens is to ozone under realistic conditions in the field. Eighteen saplings were exposed to ozone in a contaminated area and in a greenhouse with filtered air during two exposure periods of approximately 63 days each (March-May 2012 and September-October 2012). Leaf injury was analyzed by means of its incidence and severity, the leaf injury index (LII) and the progression of leaf abscission. These variables were monitored weekly, whereas growth and lipid peroxidation were monitored monthly. Plants exposed to ozone showed significant growth decrease and visible leaf injury increase, but lipid peroxidation and leaf abscission remained unchanged. These results indicated that plants subjected to ozone possibly diverted energy from growth to the production of antioxidants necessary to cope with ozone-induced oxidative stress. PMID:26780049

  12. A STUDY OF THE POTENTIAL WAYS IN WHICH OZONE COULD REDUCE ROOT GROWTH AND NODULATION OF SOYBEAN

    The possible mechanisms by which the ozone reduces root growth and nodulation of soybean were investigated. Ozone did not appreciably penetrate the plant growth substrates nor did it oxidize soil organic matter to form compounds inhibitory to Rhizobium. When ozone was excluded fr...

  13. Effects of ozone and sulfur dioxide on virus growth in mice.

    Fairchild, G A

    1977-01-01

    Inhalation of ozone and sulfur dioxide inhibited influenza virus growth in the nose of mice. Ozone inhalation caused the more pronounced inhibition of influenza virus growth: 0.6 ppm ozone for 3 hours post-virus exposure almost completely inhibited influenza virus growth in the nose, whereas sulfur dioxide (6 ppm for 7 days) causes only partial inhibition of influenza growth in the nose. Neither gas altered the propagation of influenza virus in the lungs of mice. Vesicular stomatitis virus (VSV) growth was either unaffected by exposure to ozone (0.9 ppm for 3 hours) or, when ozone exposure preceeded VSV exposure, the virus may have grown to slightly higher titer. The inhibitory effect of ozone and sulfur dioxide on influenza virus growth in nasal epithelium suggests a competitive interaction between the chemical inhalant, the virus, and host tissues, with net consequences for the pathogenesis of this disease. If the effcts of these inhalants are to be properly interpreted, they should be determined for all major regions of virus growth and inhalant deposition. PMID:189703

  14. STUDY OF THE INFLUENCE OF OZONE ON THE GROWTH PROCESSES OF MAIZE SEEDS

    Shevchenko A. A.

    2015-01-01

    Full Text Available Increasing the yield of crops is a global challenge substantiated by the scientists from all over the world. To achieve this goal, there are various ways, one of which is the ozonation of seeds before sowing. This method inhibits harmful microflora, which could be formed on the seed during the period of storage, and excites the chemical processes within the seed that can accelerate the process of growth. But despite the positive effect of ozone-air mixture of seeds and a variety of conducting research there is still no reliable data on the technological parameters of ozone effects on seed crops (e.g., corn. In this regard, we have conducted experimental studies to determine the effective parameters of the ozonation of corn seeds, such as the concentration of ozone in the ozone-air mixture, exposure time and binning after treatment. The influence of these parameters was assessed by changes in growth performance of seed, such as germination, germination and growth of strength. Just at the end of the pilot study we carried out a statistical analysis of the data, which allowed us to estimate the degree of influence of each independent parameter (ozone concentration, exposure time, binning after treatment for each dependent parameter (germination energy, germination, growth force. The data obtained is presented in the article

  15. Ambient ozone effects on gas exchange and total non-structural carbohydrate levels in cutleaf coneflower (Rudbeckia laciniata L.) growing in Great Smoky Mountains National Park

    Ozone-sensitive and -tolerant individuals of cutleaf coneflower (Rudbeckia laciniata L.) were compared for their gas exchange characteristics and total non-structural carbohydrates at Purchase Knob, a high elevation site in Great Smoky Mountains National Park, USA. Photosynthesis and stomatal conductance decreased with increased foliar stipple. Sensitive plants had lower photosynthetic rates for all leaves, except the very youngest and oldest when compared to tolerant plants. Stomatal conductance decreased with increasing leaf age, but no ozone-sensitivity differences were found. Lower leaves had less starch than upper ones, while leaves on sensitive plants had less than those on tolerant plants. These results show that ambient levels of ozone in Great Smoky Mountains National Park can adversely affect gas exchange, water use efficiency and leaf starch content in sensitive coneflower plants. Persistence of sensitive genotypes in the Park may be due to physiological recovery in low ozone years. - Highlights: ► Ozone-sensitive and -tolerant cutleaf coneflower (Rudbeckia laciniata L.) were compared. ► Net photosynthesis decreased with increased foliar stipple and leaf age. ► Sensitive plants with visible stipple had lower photosynthetic rates when compared to tolerant plants. ► Stomatal conductance did not differ between sensitivity types. ► Sensitive plants had lower leaf starch content than tolerant plants. - Ambient ozone may cause declines in gas exchange and starch in ozone-sensitive genotypes of cutleaf coneflower.

  16. Growth of Chironomus dilutus larvae exposed to ozone-treated and untreated oil sands process water

    Oil sand processing operations require large quantities of freshwater and produce large volumes of oil sands process water (OSPW) which must be stored on-site. This presentation reviewed various treatment methods for remediating OSPW in order to eliminate downstream toxicity. Naphthenic acids are the most important target fractions for treatment because they are primarily responsible for the acute toxicity of OSPW. Although ozonation has shown promise for reducing OSPW toxicity, the effects of ozonation on aquatic invertebrates remain unknown. This study investigated the effects of exposure to untreated and ozonated OSPW in Chironomus dilutus larvae. OSPW was treated with either a 50 or 80 mg O3/L dose of ozonation. The effects of ozonation levels on C. dilutus survival and growth were examined. The study showed that after a 10-day exposure, there were pronounced effects on survival of larvae exposed to ozone-treated or untreated OSPW. Larvae exposed to OSPW were 64-77 percent smaller than their respective controls, but the mean wet mass of organisms exposed to 50 mg O3/L ozonated OSPW was not much different from that of the controls. Larvae exposed to 80 mg O3/L ozone-treated OSPW were 40 percent smaller than the freshwater controls, and the mean wet mass was also much larger than the untreated OSPW. It was concluded that the toxicity of OSPW to benthic invertebrates may be reduced by ozone treatment.

  17. Spatial interpolation of ambient ozone concentrations from sparse monitoring points in Belgium.

    Hooyberghs, Jef; Mensink, Clemens; Dumont, Gerwin; Fierens, Frans

    2006-11-01

    Due to scientific interest on the one hand and political and regulatory obligations on the other hand the monitoring of ozone in the troposphere is an important issue. To this end, in Belgium as in many other countries, a fixed network of monitoring stations is operated. In order to estimate the ozone concentrations over the whole territory, a model is needed to spatially complement the sparse measurements. This paper describes the development of an interpolation scheme which is aimed at fast operational use. The model uses the population density as auxiliary data to remove a spatial trend due to titration by nitric oxide. The residuals are interpolated by kriging. As a benchmark the inverse distance weighting interpolation method is used with and without the detrending. The proposed model systematically improves the interpolation and makes a significant difference when estimating human exposure to ozone. It is generic in design, easy to implement and flexible to changes in the monitoring network. PMID:17075619

  18. Ozone fumigation (twice ambient) reduces leaf infestation following natural and artificial inoculation by the endophytic fungus Apiognomonia errabunda of adult European beech trees

    Olbrich, Maren; Knappe, Claudia; Wenig, Marion; Gerstner, Elke [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Haeberle, Karl-Heinz; Kitao, Mitsutoshi; Matyssek, Rainer [Forest Botany, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Stich, Susanne [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Leuchner, Michael; Werner, Herbert [Bioclimatology, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Schlink, Katja; Mueller-Starck, Gerhard [Section of Forest Genetics, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Welzl, Gerhard [Institute of Developmental Genetics, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Scherb, Hagen [Institute of Biomathematics and Biometry, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Ernst, Dieter; Heller, Werner [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany); Bahnweg, Guenther, E-mail: bahnweg@helmholtz-muenchen.d [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, 85764 Neuherberg (Germany)

    2010-04-15

    In 2006, a controlled infection study was performed in the 'Kranzberger Forst' to address the following questions: (1) Will massive artificial inoculation with Apiognomonia errabunda override the previously observed inhibitory effect of chronic ozone? (2) Can biochemical or molecular markers be detected to account for the action of ozone? To this end six adult beech trees were chosen, three ozone fumigated (2x ozone) and three control trees (ambient = 1x ozone). Spore-sprayed branches of sun and shade crown positions of each of the trees, and uninoculated control branches, were enclosed in 100-L plastic bags for one night to facilitate infection initiation. Samples were taken within a five-week period after inoculation. A. errabunda infestation levels quantified by real-time PCR increased in leaves that were not fumigated with additional ozone. Cell wall components and ACC (ethylene precursor 1-amino cyclopropane-1-carboxylic acid) increased upon ozone fumigation and may in part lead to the repression of fungal infection. - Chronic sublethal ozone exposure reduces both natural and artificial infestation of beech leaves by the endophytic fungus Apiognomonia errabunda.

  19. Ozone fumigation (twice ambient) reduces leaf infestation following natural and artificial inoculation by the endophytic fungus Apiognomonia errabunda of adult European beech trees

    In 2006, a controlled infection study was performed in the 'Kranzberger Forst' to address the following questions: (1) Will massive artificial inoculation with Apiognomonia errabunda override the previously observed inhibitory effect of chronic ozone? (2) Can biochemical or molecular markers be detected to account for the action of ozone? To this end six adult beech trees were chosen, three ozone fumigated (2x ozone) and three control trees (ambient = 1x ozone). Spore-sprayed branches of sun and shade crown positions of each of the trees, and uninoculated control branches, were enclosed in 100-L plastic bags for one night to facilitate infection initiation. Samples were taken within a five-week period after inoculation. A. errabunda infestation levels quantified by real-time PCR increased in leaves that were not fumigated with additional ozone. Cell wall components and ACC (ethylene precursor 1-amino cyclopropane-1-carboxylic acid) increased upon ozone fumigation and may in part lead to the repression of fungal infection. - Chronic sublethal ozone exposure reduces both natural and artificial infestation of beech leaves by the endophytic fungus Apiognomonia errabunda.

  20. Cardiac Effects of Seasonal Ambient Particulate Matter and Ozone Co-exposure in Rats

    BackgroundThe potential for seasonal differences in the physicochemical characteristics of ambient particulate matter (PM) to modify interactive effects with gaseous pollutants has not been thoroughly examined. The purpose of this study was to compare cardiac responses in conscio...

  1. Genotypic variation in growth and physiological responses of Finnish hybrid aspen (Populus tremuloides x P. tremula) to elevated tropospheric ozone concentration.

    Oksanen, E; Amores, G; Kokko, H; Amores, J M; Kärenlampi, L

    2001-10-01

    Saplings of six Finnish hybrid aspen (Populus tremuloides Michx. x P. tremula L.) clones were exposed to 0, 50, 100 and 150 ppb ozone (O3) for 32 days in a chamber experiment to determine differences in O3 sensitivity among genotypes. Based on the chamber experiment, three clones with intermediate sensitivity to O3 were selected for a free-air O3 enrichment experiment in which plants were exposed for 2 months to either ambient air (control) or air containing 1.3 x the ambient O3 concentration. We measured stem height and radial growth, number of leaves, dry mass and relative growth rate of leaves, stem and roots, visible leaf injuries, net photosynthesis and stomatal conductance of the clones. There was high clonal variation in susceptibility to O3 in the chamber experiment, indicated by foliar injuries and differential reductions in growth and net photosynthesis. In the free-air O3 enrichment experiment, ozone caused a shift in resource allocation toward stem height growth, thereby altering the shoot to root balance. In both experiments, low O3 concentrations tended to stimulate growth of most clones, whereas 100 and 150 ppb O3 in the chamber experiment impaired growth of most clones. However, growth of the most O3-tolerant clone was not significantly affected by any O3 treatment. PMID:11600339

  2. EPITHELIAL INJURY AND INTERSTITIAL FIBROSIS IN THE PROXIMAL ALVEOLAR REGIONS OF RATS CHRONICALLY EXPOSED TO A SIMULATED PATTERN OF URBAN AMBIENT OZONE

    Electron microscopic morphometry was used to study the development of lung injury during and after chronic (78 weeks) exposure to a pattern of ozone designed to simulate high urban ambient concentrations that occur in some environments. he dolly exposure regimen consisted of a 1 ...

  3. Southwestern Tropical Atlantic coral growth response to atmospheric circulation changes induced by ozone depletion in Antarctica

    Evangelista, H.; Wainer, I.; Sifeddine, A.; Corrège, T.; Cordeiro, R. C.; Lamounier, S.; Godiva, D.; Shen, C.-C.; Le Cornec, F.; Turcq, B.; Lazareth, C. E.; Hu, C.-Y.

    2015-08-01

    Climate changes induced by stratospheric ozone depletion over Antarctica have been recognized as an important consequence of the recently observed Southern Hemisphere atmospheric circulation. Here we present evidences that the Brazilian coast (Southwestern Atlantic) may have been impacted from both winds and sea surface temperature changes derived from this process. Skeleton analysis of massive coral species living in shallow waters off Brazil are very sensitive to air-sea interactions, and seem to record this impact. Growth rates of Brazilian corals show a trend reversal that fits the ozone depletion evolution, confirming that ozone impacts are far reaching and potentially affect coastal ecosystems in tropical environments.

  4. Host location behavior of Cotesia plutellae Kurdjumov (Hymenoptera: Braconidae) in ambient and moderately elevated ozone in field conditions

    Pinto, D.M. [Department of Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio (Finland)], E-mail: delia.pinto@uku.fi; Himanen, S.J. [Department of Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio (Finland); Nissinen, A. [Department of Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio (Finland); Agrifood Research Finland, Plant Protection, FIN-31600 Jokioinen (Finland); Nerg, A.-M.; Holopainen, J.K. [Department of Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio (Finland)

    2008-11-15

    In field O{sub 3}-enrichment experiments increased herbivore densities have been reported, which could be due to negatively affected host location behavior of natural enemies. We addressed the impact of doubling background O{sub 3} on the host location of the parasitoid Cotesia plutellae by conducting 24-h trials in an open-air O{sub 3}-fumigation system during two consecutive years. Two circles (radii 1.40 and 4.00 m) of Plutella xylostella-infested potted cabbage plants were placed in the O{sub 3} and ambient plots. Female wasps were released into each plot from the center, and observed 5 times over a 24-h period to assess their host location capability. Thereafter, plants were kept in laboratory conditions until larvae pupation to determine parasitism rates. No significant differences were detected between ambient and O{sub 3}-enriched environments either in the number of wasps found in the field, or in the percentages of parasitized larvae. This suggests that moderately elevated O{sub 3} will not affect the behavior of this parasitoid. - Atmospheric ozone increases do not directly affect the biological control of the cabbage pest, Plutella xylostella.

  5. Host location behavior of Cotesia plutellae Kurdjumov (Hymenoptera: Braconidae) in ambient and moderately elevated ozone in field conditions

    In field O3-enrichment experiments increased herbivore densities have been reported, which could be due to negatively affected host location behavior of natural enemies. We addressed the impact of doubling background O3 on the host location of the parasitoid Cotesia plutellae by conducting 24-h trials in an open-air O3-fumigation system during two consecutive years. Two circles (radii 1.40 and 4.00 m) of Plutella xylostella-infested potted cabbage plants were placed in the O3 and ambient plots. Female wasps were released into each plot from the center, and observed 5 times over a 24-h period to assess their host location capability. Thereafter, plants were kept in laboratory conditions until larvae pupation to determine parasitism rates. No significant differences were detected between ambient and O3-enriched environments either in the number of wasps found in the field, or in the percentages of parasitized larvae. This suggests that moderately elevated O3 will not affect the behavior of this parasitoid. - Atmospheric ozone increases do not directly affect the biological control of the cabbage pest, Plutella xylostella

  6. 78 FR 34964 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    2013-06-11

    ... Federal Register on June 6, 2013, (78 FR 34178) and is available at: http://www.epa.gov/air/ozonepollution... on June 6, 2013, (78 FR 34178) and is available at http://www.epa.gov/air/ozonepollution/actions.html... AGENCY 40 CFR Parts 50, 51, 70 and 71 Implementation of the 2008 National Ambient Air Quality...

  7. ambiental

    Roque Leal Salcedo

    2008-01-01

    Full Text Available El derecho internacional ambiental es un conocimiento de carácter transversal, que entre otras consideraciones refleja las preocupaciones de la sociedad por la implementación de un modelo de desarrollo sustentable para el respeto a las reglas del medio natural que garantizan la integridad y renovación de los sistemas naturales. El presente artículo enfoca esta visión a través del análisis de material documental revisado, entre ellos tratados internacionales que permiten distinguir el desarrollo del derecho internacional ambiental y el papel de Organización de las Naciones Unidas (ONU, en el propósito común del derecho individual y colectivo de disfrutar de una vida, un ambiente seguro, sano y ecológicamente equilibrado. En función a estas disertaciones las consideraciones finales exponen parte de la visión que ha estructurado la ONU y que representan un aporte considerable en el fomento de la conciencia mundial sobre la necesidad de establecer vínculos entre las naciones para el continuo desarrollo de esta rama del derecho.

  8. Effects of ozone on growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat (Triticum aestivum L.)

    Akhtar, Nahid [United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509 (Japan); Yamaguchi, Masahiro; Inada, Hidetoshi; Hoshino, Daiki; Kondo, Taisuke [Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509 (Japan); Izuta, Takeshi, E-mail: izuta@cc.tuat.ac.j [Institute of Symbiotic Science and Technology, Tokyo University of Agriculture and Technology, Fuchu, Tokyo 183-8509 (Japan)

    2010-05-15

    To clarify the effects of O{sub 3} on crop plants cultivated in Bangladesh, two Bangladeshi wheat cultivars (Sufi and Bijoy) were grown in plastic boxes filled with Andisol and exposed daily to charcoal-filtered air or O{sub 3} at 60 and 100 nl l{sup -1} (10:00-17:00) from 13 March to 4 June 2008. The whole-plant dry mass and grain yield per plant of the two cultivars at the final harvest were significantly reduced by the exposure to O{sub 3}. Although there was no significant effect of O{sub 3} on stomatal diffusive conductance to H{sub 2}O of flag leaf, net photosynthetic rate of the leaf was significantly reduced by the exposure to O{sub 3.} The sensitivity of growth, yield, yield components and leaf gas exchange rates to O{sub 3} was not significantly different between the two cultivars. The results obtained in the present study suggest that ambient levels of O{sub 3} may detrimentally affect wheat production in Bangladesh. - The exposure to ambient levels of ozone decreases growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat.

  9. Effects of ozone on growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat (Triticum aestivum L.)

    To clarify the effects of O3 on crop plants cultivated in Bangladesh, two Bangladeshi wheat cultivars (Sufi and Bijoy) were grown in plastic boxes filled with Andisol and exposed daily to charcoal-filtered air or O3 at 60 and 100 nl l-1 (10:00-17:00) from 13 March to 4 June 2008. The whole-plant dry mass and grain yield per plant of the two cultivars at the final harvest were significantly reduced by the exposure to O3. Although there was no significant effect of O3 on stomatal diffusive conductance to H2O of flag leaf, net photosynthetic rate of the leaf was significantly reduced by the exposure to O3. The sensitivity of growth, yield, yield components and leaf gas exchange rates to O3 was not significantly different between the two cultivars. The results obtained in the present study suggest that ambient levels of O3 may detrimentally affect wheat production in Bangladesh. - The exposure to ambient levels of ozone decreases growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat.

  10. Development of an ozone high sensitive sensor working at ambient temperature

    Hybrid SnO2/SWNTs thin layer were deposited by using sol-gel process. Such sensitive layers showed very high performances for O3 flow detection at ambient temperature. Limit sensitivity, lower than 21,5 ppb of O3 in air has been reached by using these hybrid layers. Compared to usefull metal oxide sensors, the main advantage of the use of such hybrid layers, is that these devices enable the detection of O3 traces at room temperature. The influence of sensor's working temperature is discussed and finally a reactional mechanism for the detection of O3 is proposed.

  11. Effects of simultaneous ozone exposure and nitrogen loads on carbohydrate concentrations, biomass, growth, and nutrient concentrations of young beech trees (Fagus sylvatica)

    Thomas, V.F.D. [Institute for Applied Plant Biology, Sandgrubenstr. 25/27, 4124 Schoenenbuch (Switzerland)]. E-mail: vera.thomas@iap.ch; Braun, S. [Institute for Applied Plant Biology, Sandgrubenstr. 25/27, 4124 Schoenenbuch (Switzerland); Flueckiger, W. [Institute for Applied Plant Biology, Sandgrubenstr. 25/27, 4124 Schoenenbuch (Switzerland)

    2006-09-15

    Beech seedlings were grown under different nitrogen fertilisation regimes (0, 20, 40, and 80 kg N ha{sup -1} yr{sup -1}) for three years and were fumigated with either charcoal-filtered (F) or ambient air (O{sub 3}). Nitrogen fertilisation increased leaf necroses, aphid infestations, and nutrient ratios in the leaves (N:P and N:K), as a result of decreased phosphorus and potassium concentrations. For plant growth, biomass accumulation, and starch concentrations, a positive nitrogen effect was found, but only for fertilisations of up to 40 kg N ha{sup -1} yr{sup -1}. The highest nitrogen load, however, reduced leaf area, leaf water content, growth, biomass accumulation, and starch concentrations, whereas soluble carbohydrate concentrations were enhanced. The ozone fumigation resulted in reduced leaf area, leaf water content, shoot growth, root biomass accumulation, and decreased starch, phosphorus, and potassium concentrations, increasing the N:P and N:K ratios. A combined effect of the two pollutants was detected for the leaf area and the shoot elongation, where ozone fumigation amplified the nitrogen effects. - The effects of nitrogen and ozone on growth, carbohydrate concentrations, and nutrients are mainly additive.

  12. Differential protection of ethylenediurea (EDU) against ambient ozone for five cultivars of tropical wheat

    The antiozonant EDU (ethylenediurea) was used to assess the impact of ambient O3 under field conditions on five cultivars of tropical wheat (Triticum aestivum L.). EDU solution (0 ppm and 400 ppm) was applied as soil drench (100 ml plant-1) 10 days after germination (DAG) at an interval of 12 days. EDU-treated plants showed significant increments in stomatal conductance, photosynthetic rate, variable fluorescence, total chlorophyll, ascorbic acid, proline and protein contents and protective enzymes (POX, SOD and APX) activities in HUW468, HUW510 and HUW234 cultivars, while, a reverse trend was observed for lipid peroxidation. EDU application restored grain yield significantly by maintaining higher levels of antioxidants, metabolites and enzymes in cultivars HUW468 and HUW510. Sonalika and PBW343 showed least response of measured parameters under EDU treatment suggesting their greater resistance to O3. EDU, thus proved its usefulness in screening suitable wheat cultivars for areas experiencing elevated concentrations of O3. - EDU successfully screened the sensitivity of tropical wheat cultivars to ambient O3 under natural field conditions.

  13. Differential protection of ethylenediurea (EDU) against ambient ozone for five cultivars of tropical wheat

    Singh, Shalini [Lab of Air Pollution and Global Climatic Change, Ecology Research Circle, Department of Botany, Banaras Hindu University, Varanasi 221005 (India); Agrawal, S.B., E-mail: sbagrawal56@gmail.co [Lab of Air Pollution and Global Climatic Change, Ecology Research Circle, Department of Botany, Banaras Hindu University, Varanasi 221005 (India); Agrawal, Madhoolika [Lab of Air Pollution and Global Climatic Change, Ecology Research Circle, Department of Botany, Banaras Hindu University, Varanasi 221005 (India)

    2009-08-15

    The antiozonant EDU (ethylenediurea) was used to assess the impact of ambient O{sub 3} under field conditions on five cultivars of tropical wheat (Triticum aestivum L.). EDU solution (0 ppm and 400 ppm) was applied as soil drench (100 ml plant{sup -1}) 10 days after germination (DAG) at an interval of 12 days. EDU-treated plants showed significant increments in stomatal conductance, photosynthetic rate, variable fluorescence, total chlorophyll, ascorbic acid, proline and protein contents and protective enzymes (POX, SOD and APX) activities in HUW468, HUW510 and HUW234 cultivars, while, a reverse trend was observed for lipid peroxidation. EDU application restored grain yield significantly by maintaining higher levels of antioxidants, metabolites and enzymes in cultivars HUW468 and HUW510. Sonalika and PBW343 showed least response of measured parameters under EDU treatment suggesting their greater resistance to O{sub 3}. EDU, thus proved its usefulness in screening suitable wheat cultivars for areas experiencing elevated concentrations of O{sub 3}. - EDU successfully screened the sensitivity of tropical wheat cultivars to ambient O{sub 3} under natural field conditions.

  14. Physiological and foliar symptom response in the crowns of Prunus serotina, Fraxinus americana and Acer rubrum canopy trees to ambient ozone under forest conditions

    The crowns of five canopy dominant black cherry (Prunus serotina Ehrh.), five white ash (Fraxinus americana L.), and six red maple (Acer rubrum L.) trees on naturally differing environmental conditions were accessed with scaffold towers within a mixed hardwood forest stand in central Pennsylvania. Ambient ozone concentrations, meteorological parameters, leaf gas exchange and leaf water potential were measured at the sites during the growing seasons of 1998 and 1999. Visible ozone-induced foliar injury was assessed on leaves within the upper and lower crown branches of each tree. Ambient ozone exposures were sufficient to induce typical symptoms on cherry (0-5% total affected leaf area, LAA), whereas foliar injury was not observed on ash or maple. There was a positive correlation between increasing cumulative ozone uptake (U) and increasing percent of LAA for cherry grown under drier site conditions. The lower crown leaves of cherry showed more severe foliar injury than the upper crown leaves. No significant differences in predawn leaf water potential (ψL) were detected for all three species indicating no differing soil moisture conditions across the sites. Significant variation in stomatal conductance for water vapor (gwv) was found among species, soil moisture, time of day and sample date. When comparing cumulative ozone uptake and decreased photosynthetic activity (Pn), red maple was the only species to show higher gas exchange under mesic vs. drier soil conditions (P wv and Pn demonstrate the strong influence of heterogeneous environmental conditions within forest canopies. - Within the heterogeneous environment of a mature forest, many factors in addition to soil moisture play a significant role in determining exposure/response relationships to ozone

  15. EFFECTS OF OZONE ON SPORULATION, SPORE GERMINATION, AND GROWTH OF FOMES ANNOSUS

    Effects of ozone (O3) on certain cultural characteristics of Fomes annosus were investigated in exposure chamber studies. Growth rates of F. annosus decreased and conidial germ tubes were shorter and had fewer branches as O3 dosages increased. F. annosus conidial production was v...

  16. Did the Ambient Ozone Affect Stem Increment of Scots Pines (Pinus sylvestris L.) on Territories under Regional Pollution Load? Step III of Lithuanian Studies

    Algirdas Augustaitis; Ingrida Augustaitiene; Gintautas Cinga; Juozapas Mazeika; Romualdas Deltuvas; Romualdas Juknys; Adomas Vitas

    2007-01-01

    This study aimed to explore if changes in stem increment of Scots pines (Pinus sylvestris L.) could be related to changes in ambient ozone concentration when the impact of tree dendrometric parameters (age, diameter) and crown defoliation are accounted for. More than 200 dominant and codominant trees from 12 pine stands, for which crown defoliation had been assessed since 1994, were chosen for increment boring and basal area increment computing. Stands are located in Lithuanian national parks...

  17. Ambient Ozone Control in a Photochemically Active Region: Short-Term Despiking or Long-Term Attainment?

    Ou, Jiamin; Yuan, Zibing; Zheng, Junyu; Huang, Zhijiong; Shao, Min; Li, Zekun; Huang, Xiaobo; Guo, Hai; Louie, Peter K K

    2016-06-01

    China has made significant progress decreasing the ambient concentrations of most air pollutants, but ozone (O3) is an exception. O3 mixing ratios during pollution episodes are far higher than the national standard in the Pearl River Delta (PRD), thus greater evidence-based control efforts are needed for O3 attainment. By using a validated O3 modeling system and the latest regional emission inventory, this study illustrates that control strategies for short-term O3 despiking and long-term attainment in the PRD may be contradictory. VOC-focused controls are more efficient for O3 despiking in urban and industrial areas, but significant NOx emission reductions and a subsequent transition to a NOx-limited regime are required for O3 attainment. By tracking O3 changes along the entire path toward long-term attainment, this study recommends to put a greater focus on NOx emission controls region-wide. Parallel VOC reductions around the Nansha port are necessary in summertime and should be extended to the urban and industrial areas in fall with a flexibility to be strengthened on days forecasted to have elevated O3. Contingent VOC-focused controls on top of regular NOx-focused controls would lay the groundwork for striking a balance between short-term despiking and long-term attainment of O3 concentrations in the PRD. PMID:27135547

  18. STUDY OF THE INFLUENCE OF OZONE ON THE GROWTH PROCESSES OF MAIZE SEEDS

    Shevchenko A. A.; Saprunova E. A.

    2015-01-01

    Increasing the yield of crops is a global challenge substantiated by the scientists from all over the world. To achieve this goal, there are various ways, one of which is the ozonation of seeds before sowing. This method inhibits harmful microflora, which could be formed on the seed during the period of storage, and excites the chemical processes within the seed that can accelerate the process of growth. But despite the positive effect of ozone-air mixture of seeds and a variety of conducting...

  19. Effect of increased carbon dioxide concentrations on stratospheric ozone

    During the past several years, much attention has been focused on the destruction of ozone by anthropogenic pollutants such as the nitrogen oxides and chlorofluoromethane. Little or no attention has been given to the influence on ozone of an increased carbon dioxide concentration for which a measurable growth has been observed. Increased carbon dioxide can directly affect ozone by perturbing atmospheric temperatures, which will alter ozone production, whose rate displays a fairly strong temperature dependence. This paper presents one-dimensional model results for the steady state ozone behavior when the CO2 concentration is twice its ambient level which account for coupling between chemistry and temperature. When the CO2 level doubled, the total ozone burden increased in relation to the ambient burden by 1.2--2.5%, depending on the vertical diffusion coefficient used. Above 30 km. In this region the relation variations were insensitive to the choice of diffusion coefficient. Below 30 km, ozone concentrations were smaller than the unperturbed values and were sensitive to the vertical diffusion profile in this region (10--30 km). Ozone decreases in the lower stratosphere because of a reduction in ozone-producing solar radiation, which results in smaller downward ozone fluxes from the region at 25--30 km relative to the flux values for the ambient atmosphere. These offsetting changes occurring in the upper and lower stratosphere act to minimize the variation in total ozone

  20. 75 FR 1566 - Public Hearings for Reconsideration of the 2008 National Ambient Air Quality Standards for Ozone

    2010-01-12

    ... the following Web site: http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html for the addresses.../standards/ozone/s_o3_cr_fr.html . FOR FURTHER INFORMATION CONTACT: If you would like to speak at the public... proposal at http://www.epa.gov/ttn/naaqs/standards/ozone/s_o3_cr_fr.html prior to the hearings....

  1. Evaluation of innovative air-monitoring technologies for the measurement of ambient concentrations of ozone and its precursors at the 1996 Summer Olympics

    Gamiles, Donald S.; Rodgers, Michael; Meeker, Charles; Olive, Brent S.; Simpson, Orman A.

    1997-05-01

    An open path Fourier transform IR spectrometer and an ultra- violet differential optical absorption spectrometer were used during the 1996 Atlanta Olympics games to monitor for ambient ozone and its precursors near the Olympic Village. Both systems were operated continuously before, during, and after the increase in Atlanta's population associated with the Summer games. The study utilized the massive changes in population patterns to observe and measure changes in local air quality due to an increased local population. A second goal of the program was to evaluate both open path instruments in continuous field use over a period of several weeks. The evaluation included the following criteria: instrumentation operability, system precision and accuracy, detection capability, and over-all ease of use. Both open path systems selected and measured ambient levels of ozone. A limited number of ozone precursors were detected. The study was sponsored by the Georgia Institute of Technology's Air Quality Laboratory, the US Department of Energy, and the US Environmental Protection Agency.

  2. Influence of growth ambient on the surface and structural properties of vanadium oxide nanorods

    Tien, Li-Chia; Chen, Yu-Jyun

    2013-06-01

    The influence of growth ambient on the surface and structural properties of vanadium oxide nanorods have been studied by X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy (RS). The vanadium oxide nanorods, which were synthesized through an ambient controlled vapor transport process, exhibit different surface electronic properties depending upon the growth ambient. The Raman data indicates that the as-grown samples are orthorhombic V2O5 phase with a small variation of stoichiometry. Under highly oxidative conditions, nearly stoichiometry sample can be grown. If the samples were grown under less oxidizing conditions, an increase of structural disorder was observed. The observed V 2p core level spectra of both samples showed a single peak with chemical shifts corresponding to the V5+ and V4+. XPS results suggested that the highly oxidized vanadium ions (V5+) are gradually reduced to lower oxidation state (V4+) with the decreases of ambient oxygen levels during growth. The results clearly show that surface non-stoichiometry may be correlated with structural disorder of V2O5 nanorods. The growth ambient and post-annealing may influence the vanadium oxidation state and subsequent surface reactivity significantly.

  3. Factors affecting the effects of EDU on growth and yield of field-grown bush beans (Phaseolus vulgaris L.), with varying degrees of sensitivity to ozone

    Elagoez, Vahram [Plant Biology Graduate Program, University of Massachusetts, Amherst, MA 01003 (United States)]. E-mail: velagoz@nsm.umass.edu; Manning, William J. [Department of Plant, Soil and Insect Sciences, University of Massachusetts, Amherst, MA 01003 (United States)

    2005-08-15

    The effects of foliar applications of ethylenediurea (EDU) on responses to ozone by field-grown bush bean (Phaseolus vulgaris L.) lines 'S156' (O{sub 3}-sensitive) and 'R123' (O{sub 3}-tolerant), and cultivars 'BBL 290' (O{sub 3}-sensitive) and 'BBL 274' (O{sub 3}-tolerant) were investigated during the 2001 and 2002 growing seasons. EDU was applied weekly to designated plants between primary leaf expansion and pod senescence. Results were compared with control plants at harvests made at pod maturation and pod senescence. In 2001, average hourly ambient O{sub 3} concentrations ranged between 41 and 59 ppb for a total of 303 h; in 2002, for 355 h. EDU applications prior to pod maturation significantly increased the number of marketable pods in 'R123', but not for the other cultivars. Harvests at pod senescence showed significant improvements in crop yield production in EDU-treated 'S156' plants, whereas for EDU-treated 'R123' plants significant reductions were determined in above-ground biomass and seed production. In contrast, results from 'BBL 290' and 'BBL 274' at both harvest points were inconclusive. Growth and reproductive responses of O{sub 3}-sensitive and O{sub 3}-tolerant bush bean plants to EDU applications varied, depending on developmental stages, duration of EDU applications, and fluctuations in ambient O{sub 3}. - Plant sensitivity to ozone, stage of plant development, number of applications of EDU and ambient ozone affect bean plant responses to EDU.

  4. Changes in the Community of Ectomycorrhizal Fungi and Increased Fine Root Number Under Adult Beech Trees Chronically Fumigated with Double Ambient Ozone Concentration

    Grebenc, Tine; Kraigher, Hojka

    2007-01-01

    Forest soils are an important but under-studied part of forest ecosystems. The effects of O3 on below-ground processes in a mature forest have only received limited attention so far. In our study, we have analysed the community of ectomycorrhizal fungi and beech fine root dynamics over two growing seasons (2003–2004) in a 70-year old mixed spruce-beech forest stand, in which two groups of five adult beech trees were either fumigated by 2 × ambient ozone concentration or used as control. The m...

  5. The Influence of Ozonization For DO, BOD and Bacterial Growth in The Liquid Waste From Tanning Leather Industry

    The research of ozonization influence of dissolved oxygen (DO), biological oxygen demand (BOD) and the bacterial growth in the liquid waste from tanning leather industry has been done. The objectives of this research was to studied the influence of ozonization for decomposition process of the organic compound in these waste by indicator of BOD decreased, increased of DO and decomposer bacterial growth. The ozonization was carried out by time variation 0, 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165, 180, 195 and 210 minutes. Each samples of the waste has been ozonized keep in the sterile reaction tube for isolated of bacterial and the other keep in the bottle for BOD and DO measurement. These research results show that ozonization with 16.243 x 10-4 mg/second debit for 3 hours can decreased of BOD were 19.61 %, and ozonization for 3.5 hours can increased of DO were 82.5%. The other hand, 3 hours ozonization can decreased of kind of bacterial growth were 80 %. (author)

  6. Inhibitory effects of ambient levels of solar UV-A and UV-B radiation on growth of cucumber

    The influence of solar UV-A and UV-B radiation at Beltsville, Maryland, on growth and flavonoid content in four cultivars of Cucumis sativus L. (Ashley, Poinsett, Marketmore, and Salad Bush cucumber) was examined during the summers of 1994 and 1995. Plants were grown from seed in UV exclusion chambers consisting of UV-transmitting Plexiglas, lined with Llumar to exclude UV-A and UV-B, polyester to exclude UV-B, or cellulose acetate to transmit UV-A and UV-B. Despite previously determined differences in sensitivity to supplemental UV-B radiation, all four cultivars responded similarly to UV-B exclusion treatment. After 19–21 days, the four cultivars grown in the absence of solar UV-B (polyester) had an average of 34, 55, and 40% greater biomass of leaves, stems, and roots, respectively, 27% greater stem height, and 35% greater leaf area than those grown under ambient UV-B (cellulose acetate). Plants protected from UV-A radiation as well (Llumar) showed an additional 14 and 22% average increase, respectively, in biomass of leaves and stems, and a 22 and 19% average increase, respectively, in stem elongation and leaf area over those grown under polyester. These findings demonstrate the extreme sensitivity of cucumber not only to present levels of UV-B but also to UV-A and suggest that even small changes in ozone depletion may have important biological consequences for certain plant species. (author)

  7. Ideas and perspectives: Southwestern tropical Atlantic coral growth response to atmospheric circulation changes induced by ozone depletion in Antarctica

    Evangelista, Heitor; Wainer, Ilana; Sifeddine, Abdelfettah; Corrège, Thierry; Cordeiro, Renato C.; Lamounier, Saulo; Godiva, Daniely; Shen, Chuan-Chou; Le Cornec, Florence; Turcq, Bruno; Lazareth, Claire E.; Hu, Ching-Yi

    2016-04-01

    Recent Southern Hemisphere (SH) atmospheric circulation, predominantly driven by stratospheric ozone depletion over Antarctica, has caused changes in climate across the extratropics. Here, we present evidence that the Brazilian coast (southwestern Atlantic) may have been impacted from both wind and sea-surface temperature changes derived from this process. Skeleton analysis of massive coral species living in shallow waters off Brazil are very sensitive to air-sea interactions, and seem to record this impact. Growth rates of Brazilian corals show a trend reversal that fits the ozone depletion evolution, confirming that ozone impacts are far reaching and potentially affect coastal ecosystems in tropical environments.

  8. Mycorrhizal status of an ozone-sensitive poplar clone treated with the antiozonant ethylene diurea

    Katanić, Marina; Paoletti, Elena; Orlović, Saša; Grebenc, Tine; Kraigher, Hojka

    2014-01-01

    The antiozonant ethylene diurea is proven to prevent growth reductions in forest trees induced by ozone. The community of mycorrhizal fungi could be useful indicator of environmental stress. In this study, response of mycorrhizal fungi and fine roots to a 4-year exposure to ambient ozone and treatment with antiozonant was investigated in ozone-sensitive poplar clone under field conditions. The community of ectomycorrhizal fungi and root length colonization with ectomycorrhizal, arbuscular myc...

  9. Growth, radiation use efficiency, and canopy reflectance of wheat and corn grown under elevated ozone and carbon dioxide atmosphere

    Estimates of increases in future agricultural production in response to increases in carbon dioxide (CO2) concentrations in the atmosphere are often based on the beneficial physiological effect of CO2 enrichment on plant growth, especially in Ca plants. However, these estimates fail to consider the negative impact of ozone (O3) air pollution on crop production. Increases in tropospheric concentrations of both gases, CO2 and O3, have been observed over the past century, and both are predicted to continue to increase at even higher rates in the near future to levels when they may have a significant impact on agricultural production. Field studies with wheat (Friticum aestivum L.) in 1991 and 1992, and corn (Zea mays L.) in 1991 were conducted using open-top chambers to mimic atmospheric concentrations of CO2 (~ 500 μL-1 CO2) and Oa (- 40 nL L-1 O3 above ambient air [O3] during 7 h day- 1, 5 days week-1) that are predicted to occur at the Earth's surface during the first half of the 21st century. Wheat and corn (C3 vs. C4) produced clearly different responses to CO2 enrichment, but similar responses to O3 exposure. In wheat, O3 exposure led to reduced grain yield, biomass, and radiation use efficiency (RUE, phytomass production per unit of energy received); in both years; but reduction in accumulated absorbed photosynthetically active radiation (AAPAR) was observed only in 1991. Conversely, CO2 enrichment produced greater grain yield, dry biomass, and RUE. With CO2 enrichment, the Oa-induced stress to wheat plants was apparently ameliorated since responses were equivalent to the control group (low O3 and ambient CO2) for all variables. In contrast, corn demonstrated no benefit to CO2 enrichment for measured variables, and corn grain yield was the only parameter negatively influenced by O3 exposure that is attributed to O3-induced damage during the flowering process. Additionally, no treatment differences were observed for leaf area index (LAI) as determined

  10. Photochemical model evaluation of the ground-level ozone impacts on ambient air quality and vegetation health in the Alberta oil sands region: Using present and future emission scenarios

    Vijayaraghavan, Krish; Cho, Sunny; Morris, Ralph; Spink, David; Jung, Jaegun; Pauls, Ron; Duffett, Katherine

    2016-09-01

    One of the potential environmental issues associated with oil sands development is increased ozone formation resulting from NOX and volatile organic compound emissions from bitumen extraction, processing and upgrading. To manage this issue in the Athabasca Oil Sands Region (AOSR) in northeast Alberta, a regional multi-stakeholder group, the Cumulative Environmental Management Association (CEMA), developed an Ozone Management Framework that includes a modelling based assessment component. In this paper, we describe how the Community Multi-scale Air Quality (CMAQ) model was applied to assess potential ground-level ozone formation and impacts on ambient air quality and vegetation health for three different ozone precursor cases in the AOSR. Statistical analysis methods were applied, and the CMAQ performance results met the U.S. EPA model performance goal at all sites. The modelled 4th highest daily maximum 8-h average ozone concentrations in the base and two future year scenarios did not exceed the Canada-wide standard of 65 ppb or the newer Canadian Ambient Air Quality Standards of 63 ppb in 2015 and 62 ppb in 2020. Modelled maximum 1-h ozone concentrations in the study were well below the Alberta Ambient Air Quality Objective of 82 ppb in all three cases. Several ozone vegetation exposure metrics were also evaluated to investigate the potential impact of ground-level ozone on vegetation. The chronic 3-months SUM60 exposure metric is within the CEMA baseline range (0-2000 ppb-hr) everywhere in the AOSR. The AOT40 ozone exposure metric predicted by CMAQ did not exceed the United Nations Economic Commission for Europe (UN/ECE) threshold of concern of 3000 ppb-hr in any of the cases but is just below the threshold in high-end future emissions scenario. In all three emission scenarios, the CMAQ predicted W126 ozone exposure metric is within the CEMA baseline threshold of 4000 ppb-hr. This study outlines the use of photochemical modelling of the impact of an industry (oil

  11. Linking changes in ozone to changes in emissions and meteorology

    Estimation of trends in ozone air quality is a complex problem because of the strong influence of meteorology on ozone and its precursors. In this paper we present a physically-consistent methodology to link changes in ozone to changes in precursor emissions in the presence of meteorological fluctuations. Time series ozone concentrations (O3), nitrogen oxides (NOx) and non-methane hydrocarbons (NMHC) measured from 1985 to 1993 in the Los Angeles Air Basin are first separated into different time scales using the Kolmogorov-Zurbenko (KZ) filter. Linear regression analysis is performed on meteorological variables and ozone and its precursors on each time scale. The downward trend in the daily hourly maxima of O3 is about twice that in the daily hourly mean O3. The results demonstrate that emission control programs implemented over Southern California were very effective in improving ambient ozone levels during a period of robust economic growth. (Author)

  12. Growth of β-Ga2O3 single crystals using vertical Bridgman method in ambient air

    Hoshikawa, K.; Ohba, E.; Kobayashi, T.; Yanagisawa, J.; Miyagawa, C.; Nakamura, Y.

    2016-08-01

    A new approach to β-Ga2O3 single crystal growth was studied, using the vertical Bridgman (VB) method in ambient air, while measuring the β-Ga2O3 melting temperature and investigating the effects of crucible composition and shape. β-Ga2O3 single crystals 25 mm in diameter were grown in platinum-rhodium alloy crucibles in ambient air, with no adhesion of the crystals to the crucible wall. Single crystal growth without a crystal seed was realized by (100) faceted growth with a growth direction perpendicular to the (100) faceted plane.

  13. Vertical and Horizontal Measurements of Ambient Ozone over a Gas and Oil Production Area using a UAV Platform

    Jensen, A.; Gowing, I.; Martin, R. S.

    2013-12-01

    During the 2013 wintertime Uintah Basin Ozone Study (UBOS13), an autonomous unmanned aerial vehicle (UAV) platform, coupled with an on-board UV ozone monitor, flew several spatial profiles near the location (Horse Pool) of other concentrated measurements by other co-investigators. The airframe, part of the Utah Water Research Laboratory's (UWRL) AggieAir UAV program, consisted of a custom-built, battery-operated plane with and 2.4 m (8 ft) wing span and a 12.7 cm x 12.7 cm x 30.5 cm payload bay with a carrying capacity of approximately 2.0 kg. With the current power system, the fully-loaded AggieAir UAV can fly for approximately 45 minutes at a nominal airspeed of 13.4 m/s (30 mph). The system can be operated either in manual control or be flown autonomously following preprogrammed waypoints via a built in GPS system. The AggieAir UAV systems were primarily designed for photographic and telemetry tracking projects. For the UBOS13 flights, a 2B Technologies Model 205 Ozone (O3) monitor was modified for minimal weight optimization, wrapped with lightweight insulation and secured into the UAV payload bay. Additionally, HOBO Model H08-001-02 shielded temperature/datalogger was secured to the exterior of the UAV from parallel thermal profile determination. During the study period, three demonstration flight profiles were obtained on February 17 and 18, 2013: two vertical 'curtain' profiles and a pair of 'stacked' horizontal profiles. As recorded by numerous ground-based monitoring sites, the ozone during the UAV test periods was characterized by initial trends of daytime O3 maximums over 130 ppb, followed by a meteorological front partially ventilating the Basin on the evening of Feb. 17th leading to decreased O3 minimums around 40 ppb. However, the ground level O3 rebuilt quickly to ground level maximums approaching 100 ppb. The vertical 'curtain' flown on the evening of Feb. 17th only reached a maximum elevation of about 2160 m ASL (600 m AGL) due to encountering

  14. Ozone affects growth and development of Pieris brassicae on the wild host plant Brassica nigra

    When plants are exposed to ozone they exhibit changes in both primary and secondary metabolism, which may affect their interactions with herbivorous insects. Here we investigated the performance and preferences of the specialist herbivore Pieris brassicae on the wild plant Brassica nigra under elevated ozone conditions. The direct and indirect effects of ozone on the plant-herbivore system were studied. In both cases ozone exposure had a negative effect on P. brassicae development. However, in dual-choice tests larvae preferentially consumed plant material previously fumigated with the highest concentration tested, showing a lack of correlation between larval preference and performance on ozone exposed plants. Metabolomic analysis of leaf material subjected to combinations of ozone and herbivore-feeding, and focussing on known defence metabolites, indicated that P. brassicae behaviour and performance were associated with ozone-induced alterations to glucosinolate and phenolic pools. - Highlights: • We examined the effects of ozone on Pieris brassicae performance and preference. • We studied ozone and herbivore induced changes in the metabolome of Brassica nigra. • The performance of P. brassicae did not correlate with preference of ozonated plants. • Ozone and herbivore-feeding stress changes the phytochemical pools of B. nigra. - Ozone indirectly reduces herbivore performance, which is associated with change in phytochemical pools, but does not correlate with host plant preference

  15. Gas exchange and chlorophyll fluorescence of pea (Pisum sativum L.) plants in response to ambient ozone at a rural site in Egypt

    Egyptian pea cultivars (Pisum sativum L. cultivars Little Marvel, Perfection and Victory) grown in open-top chambers were exposed to either charcoal-filtered (FA) or non-filtered air (NF) for five consecutive years (2009–2013) at a rural site in northern Egypt. Net photosynthetic rates (PN), stomatal conductance (gs), intercellular CO2 (Ci) and chlorophyll fluorescence were measured. Ozone (O3) was found to be the most prevalent pollutant common at the rural site and is suspected to be involved in the alteration of the physiological parameters measured in the present investigation. PN of different cultivars were found to respond similarly; decreases of 23, 29 and 39% were observed in the cultivars Perfection, Little Marvel and Victory, respectively (averaged over the five years) due to ambient O3. The maximum impairment in PN was recorded in the cultivar Victory (46%) in 2013 when the highest O3 levels were recorded (90 nL L−1). The average stomatal conductance decreased by 20 and 18% in the cultivars Little Marvel and Perfection, respectively, while the average stomatal conductance increased on average by 27% in the cultivar Victory. A significant correlation was found between PN and Ci, indicating the importance of non-stomatal limitations of photosynthesis, especially in the cultivar Victory. The PN vs. Ci curves were fitted to a non-rectangular hyperbolic model. The actual quantum yield (ΦPSII) and photochemical quenching coefficient (qP) were significantly decreased in the leaves of plants exposed to NF air. Non-photochemical quenching (NPQ) was increased in all cultivars. Exposure to NF air caused reductions in chlorophyll (Chl a) of 19, 16 and 30% in the Little Marvel, Perfection and Victory cultivars, respectively. - Highlights: • Ozone (O3) concentrations recorded were within the ranges of phytotoxicity. • O3 has a clear influence on the physiological parameters. • O3 decreased Photosynthetic rates, chlorophyll fluorescence parameters. • The

  16. Effects of elevated carbon dioxide and ozone on the growth and yield of potatoes (Solanum tuberosum) grown in open-top chambers

    Potato (Solanum tuberosum cv. Bintje) was grown in open-top chambers under three carbon dioxide (ambient and seasonal mean concentrations of 550 and 680 μmol mol-1 CO2) and two ozone concentrations (ambient and an 8 h day -1 seasonal mean of 50 nmol mol-1 O3) between emergence and final harvest. Periodic non-destructive measurements were made and destructive harvests were carried out at three key developmental stages (24, 49 and 101 days after emergence) to establish effects on growth and tuber yield. Season-long exposure to elevated O3 reduced above-ground dry weight at final harvest by 8.4% (P2 and O3 for any of the growth and yield variables examined. Non-destructive analyses revealed no significant effect of elevated CO2 on plant height, leaf number or green leaf area ratio. However, destructive harvests at tuber initiation and 500 deg Cd after emergence showed that above-ground dry weight (8 and 7% respectively) and tuber yield (88 and 44%) were significantly increased (P-1 CO2 treatment. Responses to 550 and 680 μmol mol-1 CO2 were not significantly different for most parameters examined, suggesting the existence of an upper limit to the beneficial influence of CO2 enrichment. Significant effects on the above-ground dry weight and tuber yield were no longer apparent at final harvest, although tuber numbers were increased (P2, particularly in the smaller size categories. The results show that the O3 treatment imposed was insufficient to reduce tuber yields and that, although elevated CO2 enhanced crop growth during the early stages of the season, this beneficial effect was not sustained to maturity. (Author)

  17. Study of ozone gas formed in the industrial radiation process with cobalt-60 and its impact on the environment; Estudo sobre o gas ozonio formado no processo de irradiacao industrial com cobalto-60 e seu impacto no meio ambiente

    Uzueli, Daniel Henrique

    2013-07-01

    The radiation processing is present in various products such as foods, medical disposable, electrical cables, gems, among others. This process aims to improve the properties, sterilize or sanitize irradiated products. In industrial irradiators facilities, electromagnetic radiation (gamma and X-rays) or electrons before they interact with the products in processing, there are a layer of air. To interact with this air layer, it causes radiolytic effects on the molecules present in the ambient atmosphere, and the main interaction are with the oxygen molecules that have their bonds broken, separating them into two highly reactive atoms that recombine with the other molecule of oxygen to form ozone gas. In this work it was studied the formation, decay and dispersion of ozone in industrial gamma irradiators facilities that use cobalt-60 as a source of radiation. The monitoring of ozone concentration was performed by optical absorption method in a commercial monitor. (author)

  18. Future impacts of distributed power generation on ambient ozone and particulate matter concentrations in the San Joaquin Valley of California.

    Vutukuru, Satish; Carreras-Sospedra, Marc; Brouwer, Jacob; Dabdub, Donald

    2011-12-01

    Distributed power generation-electricity generation that is produced by many small stationary power generators distributed throughout an urban air basin-has the potential to supply a significant portion of electricity in future years. As a result, distributed generation may lead to increased pollutant emissions within an urban air basin, which could adversely affect air quality. However, the use of combined heating and power with distributed generation may reduce the energy consumption for space heating and air conditioning, resulting in a net decrease of pollutant and greenhouse gas emissions. This work used a systematic approach based on land-use geographical information system data to determine the spatial and temporal distribution of distributed generation emissions in the San Joaquin Valley Air Basin of California and simulated the potential air quality impacts using state-of-the-art three-dimensional computer models. The evaluation of the potential market penetration of distributed generation focuses on the year 2023. In general, the air quality impacts of distributed generation were found to be small due to the restrictive 2007 California Air Resources Board air emission standards applied to all distributed generation units and due to the use of combined heating and power. Results suggest that if distributed generation units were allowed to emit at the current Best Available Control Technology standards (which are less restrictive than the 2007 California Air Resources Board standards), air quality impacts of distributed generation could compromise compliance with the federal 8-hr average ozone standard in the region. PMID:22263420

  19. Responses of selected birch (Betula pendula Roth) clones to ozone change over time.

    Oksanen, E.

    2003-06-01

    A long-term free air ozone fumigation experiment was conducted to study changes in physiological ozone responses during tree ontogeny and exposure time in ozone sensitive and tolerant clones of European white birch (Betula pendula Roth), originated from south and central Finland. The trees were grown in soil in natural microclimatic conditions under ambient ozone (control) and 1.4-1.7 x ambient (elevated) ozone from May 1996 to October 2001, and were measured for stem and foliage growth, net photosynthesis, stomatal conductance, stomatal density, visible injuries, foliar starch content and bud formation. After 6 years of exposure, the magnitude of ozone-induced growth reductions in the sensitive clone was 12-48% (significant difference), levels similar or greater than those reported earlier for 2- and 3-year-old saplings undergoing shorter exposures. In the tolerant clone, growth of these larger trees was reduced by 1-38% (significant difference in stem volume), although the saplings had previously been unaffected. In both clones, ozone stress led to significantly reduced leaf-level net photosynthesis but significantly increased stomatal conductance rates during the late summer, resulting in a lower carbon gain for bud formation and the onset of visible foliar injuries. Increasing ozone sensitivity with duration of exposure was explained by a change in growth form (relatively reduced foliage mass), a lower photosynthesis to stomatal conductance ratio during the late summer, and deleterious carry-over effects arising from the reduced number of over-wintering buds. PMID:12803615

  20. Influences of elevated ozone and carbon dioxide in growth responses of lowland hay meadow mesocosms

    We studied the effects of relatively low levels of O3 (40-50 ppb) and CO2-enrichment (+ 100 ppm) on a northern European lowland hay meadow during the summers 2002-2004 using open-top chambers (OTCs) and ground-planted mesocosms. Ozone reduced the aboveground biomass of the community (up to 40%), and four out of seven species (Campanula rotundifolia, Fragaria vesca, Trifolium medium, Vicia cracca) showed either significant growth reduction and/or visible injuries under elevated O3. However, the reductions in aboveground biomass were not reflected as changes in the dominance of different functional groups or in the total community root biomass. Elevated CO2 did not amend the detrimental effects of O3 on aboveground biomass. Elevated CO2 alone had only minor effects. An O3-induced reduction in the aboveground biomass and N pool of the community are likely to have important consequences in the nutrient cycling of the ecosystem. - Species- and parameter-specific differences found in O3 responses and CO2 amelioration in wild plants under competitive environment

  1. Influences of elevated ozone and carbon dioxide in growth responses of lowland hay meadow mesocosms

    Raemoe, Kaisa [Department of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1, P.O. Box 65, 00014 Helsinki (Finland)]. E-mail: kaisa.koivisto@helsinki.fi; Kanerva, Teri [Department of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1, P.O. Box 65, 00014 Helsinki (Finland); Nikula, Suvi [Department of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1, P.O. Box 65, 00014 Helsinki (Finland); Ojanperae, Katinka [MTT, Agrifood Research Finland, Environmental Research, 31600 Jokioinen (Finland); Manninen, Sirkku [Department of Biological and Environmental Sciences, University of Helsinki, Viikinkaari 1, P.O. Box 65, 00014 Helsinki (Finland)

    2006-11-15

    We studied the effects of relatively low levels of O{sub 3} (40-50 ppb) and CO{sub 2}-enrichment (+ 100 ppm) on a northern European lowland hay meadow during the summers 2002-2004 using open-top chambers (OTCs) and ground-planted mesocosms. Ozone reduced the aboveground biomass of the community (up to 40%), and four out of seven species (Campanula rotundifolia, Fragaria vesca, Trifolium medium, Vicia cracca) showed either significant growth reduction and/or visible injuries under elevated O{sub 3}. However, the reductions in aboveground biomass were not reflected as changes in the dominance of different functional groups or in the total community root biomass. Elevated CO{sub 2} did not amend the detrimental effects of O{sub 3} on aboveground biomass. Elevated CO{sub 2} alone had only minor effects. An O{sub 3}-induced reduction in the aboveground biomass and N pool of the community are likely to have important consequences in the nutrient cycling of the ecosystem. - Species- and parameter-specific differences found in O{sub 3} responses and CO{sub 2} amelioration in wild plants under competitive environment.

  2. Growth and nutritive quality of Poa pratensis as influenced by ozone and competition

    Interspecific plant competition has been hypothesized to alter effects of early-season ozone (O3) stress. A phytometer-based approach was utilized to investigate O3 effects on growth and nutritive quality of Poa pratensis grown in monoculture and in mixed cultures with four competitor-plant species (Anthoxanthum odoratum, Achillea millefolium, Rumex acetosa and Veronica chamaedrys). Mesocosms were exposed during April/May 2000-2002 to charcoal-filtered air + 25 ppb O3 (control) or non-filtered air + 50 ppb O3 (elevated O3). Biomass production was not affected by O3, but foliar injury symptoms were observed in May 2002. Early-season O3 exposure decreased relative food value of P. pratensis by an average of 8%, which is sufficient to have nutritional implications for its utilization by herbivores. However, forage quality response to O3 was not changed by interspecific competition. Lack of injury and nutritive quality response in P. pratensis harvested in September may reflect recovery from early-season O3 exposure. - Early-season O3 exposure decreased nutritive quality of Poa pratensis, and nutritive quality response to O3 was not altered by interspecific competition

  3. Growth and nutritive quality of Poa pratensis as influenced by ozone and competition

    Bender, J. [Institute of Agroecology, Federal Agricultural Research Centre (FAL), Bundesallee 50, 38116 Braunschweig (Germany)]. E-mail: juergen.bender@fal.de; Muntifering, R.B. [Department of Animal Sciences, Auburn University, AL 36849 (United States); Lin, J.C. [Department of Animal Sciences, Auburn University, AL 36849 (United States); Weigel, H.J. [Institute of Agroecology, Federal Agricultural Research Centre (FAL), Bundesallee 50, 38116 Braunschweig (Germany)

    2006-07-15

    Interspecific plant competition has been hypothesized to alter effects of early-season ozone (O{sub 3}) stress. A phytometer-based approach was utilized to investigate O{sub 3} effects on growth and nutritive quality of Poa pratensis grown in monoculture and in mixed cultures with four competitor-plant species (Anthoxanthum odoratum, Achillea millefolium, Rumex acetosa and Veronica chamaedrys). Mesocosms were exposed during April/May 2000-2002 to charcoal-filtered air + 25 ppb O{sub 3} (control) or non-filtered air + 50 ppb O{sub 3} (elevated O{sub 3}). Biomass production was not affected by O{sub 3}, but foliar injury symptoms were observed in May 2002. Early-season O{sub 3} exposure decreased relative food value of P. pratensis by an average of 8%, which is sufficient to have nutritional implications for its utilization by herbivores. However, forage quality response to O{sub 3} was not changed by interspecific competition. Lack of injury and nutritive quality response in P. pratensis harvested in September may reflect recovery from early-season O{sub 3} exposure. - Early-season O{sub 3} exposure decreased nutritive quality of Poa pratensis, and nutritive quality response to O{sub 3} was not altered by interspecific competition.

  4. Gas exchange and chlorophyll fluorescence of pea (Pisum sativum L.) plants in response to ambient ozone at a rural site in Egypt

    Ismail, I.M.; Basahi, J.M. [Air Pollution Laboratory (APL), Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, P. O. Box 80216, Jeddah 21589 (Saudi Arabia); Hassan, I.A., E-mail: ihassan_eg@yahoo.com [Air Pollution Laboratory (APL), Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, P. O. Box 80216, Jeddah 21589 (Saudi Arabia); Department of Botany, Faculty of Science, Alexandria University, 21526 El Shatby, Alexandria (Egypt)

    2014-11-01

    Egyptian pea cultivars (Pisum sativum L. cultivars Little Marvel, Perfection and Victory) grown in open-top chambers were exposed to either charcoal-filtered (FA) or non-filtered air (NF) for five consecutive years (2009–2013) at a rural site in northern Egypt. Net photosynthetic rates (P{sub N}), stomatal conductance (g{sub s}), intercellular CO{sub 2} (C{sub i}) and chlorophyll fluorescence were measured. Ozone (O{sub 3}) was found to be the most prevalent pollutant common at the rural site and is suspected to be involved in the alteration of the physiological parameters measured in the present investigation. P{sub N} of different cultivars were found to respond similarly; decreases of 23, 29 and 39% were observed in the cultivars Perfection, Little Marvel and Victory, respectively (averaged over the five years) due to ambient O{sub 3}. The maximum impairment in P{sub N} was recorded in the cultivar Victory (46%) in 2013 when the highest O{sub 3} levels were recorded (90 nL L{sup −1}). The average stomatal conductance decreased by 20 and 18% in the cultivars Little Marvel and Perfection, respectively, while the average stomatal conductance increased on average by 27% in the cultivar Victory. A significant correlation was found between P{sub N} and C{sub i}, indicating the importance of non-stomatal limitations of photosynthesis, especially in the cultivar Victory. The P{sub N} vs. Ci curves were fitted to a non-rectangular hyperbolic model. The actual quantum yield (Φ{sub PSII}) and photochemical quenching coefficient (qP) were significantly decreased in the leaves of plants exposed to NF air. Non-photochemical quenching (NPQ) was increased in all cultivars. Exposure to NF air caused reductions in chlorophyll (Chl a) of 19, 16 and 30% in the Little Marvel, Perfection and Victory cultivars, respectively. - Highlights: • Ozone (O{sub 3}) concentrations recorded were within the ranges of phytotoxicity. • O{sub 3} has a clear influence on the physiological

  5. The use of ambient air quality modeling to estimate individual and population exposure for human health research: a case study of ozone in the Northern Georgia Region of the United States.

    Bell, Michelle L

    2006-07-01

    Ambient monitors are commonly used to estimate exposure for epidemiological studies, and air quality modeling is infrequently applied. However air quality modeling systems have the potential to alleviate some, although not all, of the limitations of monitoring networks. To investigate this application, exposure estimates were generated for a case study high ozone episode in the Northern Georgia Region of the United States based on measurements and concentration estimates from an air quality modeling system. Hourly estimates for 2268 4-km by 4-km gridcells were generated in a domain that includes only eight ozone monitors. Individual and population-based ozone exposures were estimated using multiple approaches, including area-weighted average of modeled estimates, nearest monitor, and spatial interpolation by inverse distance weighting and kriging. Results based on concentration fields from the air quality modeling system revealed spatial heterogeneity that was obscured by approaches based on the monitoring network. With some techniques, such as spatial interpolation, monitoring data alone was insufficient to estimate exposure for certain areas, especially for rural populations. For locations far from ozone monitors, the estimates from the nearest monitor approach tended to overestimate exposure, compared to modeled estimates. Counties in which one or more monitors were present had statistically higher population density and modeled ozone estimates than did counties without monitors (p-value <0.05). This work demonstrates the use of air quality modeling to generate higher spatial and temporal resolution exposure estimates, and compares the advantages of this approach to traditional methods that use monitoring data alone. The air quality modeling method faces its own limitations, such as the need to thoroughly evaluate concentration estimates and the use of ambient levels rather than personal exposure. PMID:16516968

  6. Fine root dynamics of mature European beech (Fagus sylvatica L.) as influenced by elevated ozone concentrations

    Fine root dynamics (diameter < 1 mm) in mature Fagus sylvatica, with the canopies exposed to ambient or twice-ambient ozone concentrations, were investigated throughout 2004. The focus was on the seasonal timing and extent of fine root dynamics (growth, mortality) in relation to the soil environment (water content, temperature). Under ambient ozone concentrations, a significant relationship was found between fine root turnover and soil environmental changes indicating accelerated fine root turnover under favourable soil conditions. In contrast, under elevated ozone, this relationship vanished as the result of an altered temporal pattern of fine root growth. Fine root survival and turnover rate did not differ significantly between the different ozone regimes, although a delay in current-year fine root shedding was found under the elevated ozone concentrations. The data indicate that increasing tropospheric ozone levels can alter the timing of fine root turnover in mature F. sylvatica but do not affect the turnover rate. - Doubling of ozone concentrations in mature European beech affected the seasonal timing of fine root turnover rather than the turnover rate.

  7. Impacts of different plant functional types on ambient ozone predictions in the Seoul Metropolitan Areas (SMA, Korea

    H.-K. Kim

    2013-09-01

    isoprene and O3 prediction results, we explored the PFT area-loss artifact that occurs due to geographical disparity between the PFT and leaf area index distributions, and can cause increased bias in CMAQ O3. Thus, the PFT-loss artifact must be a source of limitation in the MEGAN biogenic emission modeling and the CTM O3 simulation results. Time changes of CMAQ O3 distributions with the different PFT scenarios suggest that hourly and local impacts from the different PFT distributions on occasional inter-deviations of O3 are quite noticeable, reaching up to 10 ppb. Exponentially diverging hourly BVOC emissions and O3 concentrations with increasing ambient temperature suggest that the use of representative PFT distributions becomes more critical for O3 air quality modeling (or forecasting in support of air quality decision-making and human health studies.

  8. Impacts of different plant functional types on ambient ozone predictions in the Seoul Metropolitan Areas (SMAs), Korea

    Kim, H.-K.; Woo, J.-H.; Park, R. S.; Song, C. H.; Kim, J.-H.; Ban, S.-J.; Park, J.-H.

    2014-07-01

    trees (BTs) are the most significant contributor, followed by needleleaf trees (NTs), shrub (SB), and herbaceous plants (HBs) to the total BVOCs. In addition, isoprene from BTs and terpene from NTs were recognized as significant primary and secondary BVOC species in terms of BVOC emissions distributions and O3-forming potentials in the study domain. A geographically weighted regression analysis with locally compensated ridge (LCR-GWR) with the different PFT data (δO3 vs. δPFTs) suggests that addition of BT, SB, and NT areas can contribute to O3 increase, whereas addition of an HB area contributes to O3 decrease in the domain. Assessment results of the simulated spatial and temporal changes of O3 distributions with the different PFT scenarios reveal that hourly and local impacts from the different PFT distributions on occasional inter-deviations of O3 are quite noticeable, reaching up to 13 ppb. The simulated maximum 1 h O3 inter-deviations between different PFT scenarios have an asymmetric diurnal distribution pattern (low in the early morning, rising during the day, peaking at 05:00 p.m., and decreasing during the night) in the study domain. Exponentially diverging hourly BVOC emissions and O3 concentrations with increasing ambient temperature suggest that the use of different PFT distribution data requires much caution when modeling (or forecasting) O3 air quality in complicated urban atmospheric conditions in terms of whether uncertainties in O3 prediction results are expected to be mild or severe.

  9. Impacts of different plant functional types on ambient ozone predictions in the Seoul Metropolitan Areas (SMA), Korea

    Kim, H.-K.; Woo, J.-H.; Park, R. S.; Song, C. H.; Kim, J.-H.; Ban, S.-J.; Park, J.-H.

    2013-09-01

    3 prediction results, we explored the PFT area-loss artifact that occurs due to geographical disparity between the PFT and leaf area index distributions, and can cause increased bias in CMAQ O3. Thus, the PFT-loss artifact must be a source of limitation in the MEGAN biogenic emission modeling and the CTM O3 simulation results. Time changes of CMAQ O3 distributions with the different PFT scenarios suggest that hourly and local impacts from the different PFT distributions on occasional inter-deviations of O3 are quite noticeable, reaching up to 10 ppb. Exponentially diverging hourly BVOC emissions and O3 concentrations with increasing ambient temperature suggest that the use of representative PFT distributions becomes more critical for O3 air quality modeling (or forecasting) in support of air quality decision-making and human health studies.

  10. Atmospheric nitrogen dioxide at ambient levels stimulates growth and development of horticultural plants

    Adam, S.E.H.; Shigeto, J. [Hiroshima Univ., Hiroshima (Japan). Dept. of Mathematical and Life Sciences; Sakamoto, A.; Takahashi, M.; Morikawa, H. [Hiroshima Univ., Hiroshima (Japan). Dept. of Mathematical and Life Sciences, Core Research for Evolutional Science and Technology

    2008-02-15

    Studies have demonstrated that ambient levels of atmospheric nitrogen dioxide (NO{sub 2}) can cause Nicotiana plumbaginifolia to double its biomass as well as its cell contents. This paper examined the influence of NO{sub 2} on lettuce, sunflower, cucumber, and pumpkin plants. Plants were grown in environments supplemented with stable isotope-labelled NO{sub 2} for approximately 6 weeks and irrigated with nitrates. Measured growth parameters included leaf number, internode number, stem length, number of flower buds, and root length. Results of the study demonstrated that the addition of NO{sub 2} doubled the aboveground and belowground biomass of sunflowers, while only the aboveground biomass of pumpkin, cucumbers, and lettuces was doubled. Levels of carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) were also doubled in the lettuce samples. A mass spectrometry analysis showed that only a small percentage of total plant N was derived from NO{sub 2}. It was concluded that exogenous NO{sub 2} additions function as a signal rather than as a significant nutrient source in horticultural plants. 22 refs., 2 tabs., 1 fig.

  11. Atmospheric nitrogen dioxide at ambient levels stimulates growth and development of horticultural plants

    Studies have demonstrated that ambient levels of atmospheric nitrogen dioxide (NO2) can cause Nicotiana plumbaginifolia to double its biomass as well as its cell contents. This paper examined the influence of NO2 on lettuce, sunflower, cucumber, and pumpkin plants. Plants were grown in environments supplemented with stable isotope-labelled NO2 for approximately 6 weeks and irrigated with nitrates. Measured growth parameters included leaf number, internode number, stem length, number of flower buds, and root length. Results of the study demonstrated that the addition of NO2 doubled the aboveground and belowground biomass of sunflowers, while only the aboveground biomass of pumpkin, cucumbers, and lettuces was doubled. Levels of carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) were also doubled in the lettuce samples. A mass spectrometry analysis showed that only a small percentage of total plant N was derived from NO2. It was concluded that exogenous NO2 additions function as a signal rather than as a significant nutrient source in horticultural plants. 22 refs., 2 tabs., 1 fig

  12. Effects of growth retardants and fumigations with ozone and sulfur dioxide on growth and flowering of Euphorbia pulcherrima Willd

    Cathey, H.M.; Heggestad, H.E.

    1973-01-01

    Eight cultivars of poinsettia, Euphorbia pulcherrima Willd., were evaluated for sensitivity to ..cap alpha..-cyclopropyl-..cap alpha.. (4-methoxyphenyl)-5-pyrimidine methanol (ancymidol) and protection from ozone and sulfur dioxide injury afforded by applications of ancymidol and (2-chloroethyl) trimethyl ammonium chloride (chlormequat). Foliar sprays of ancymidol were at least 80 to 500 times and the soil drench 1000 times more active than chlormequat in retarding stem elongation. The diam of the bracts was reduced, but branching increased more on plants treated with ancymidol than on untreated plants. The cv. Annette Hegg (AH) was more sensitive to ozone fumigations than was Eckespoint C-1' (C-1). Sulfur dioxide also caused more injury to AH than to C-1. Ancymidol and chlormequat reduced visible injury induced by ozone and sulfur dioxide.

  13. Use of AIRS, OMI, MLS, and TES Data in Assessing Forest Ecosystem Exposure to Ozone

    Spruce, Joseph P.

    2007-01-01

    Ground-level ozone at high levels poses health threats to exposed flora and fauna, including negative impacts to human health. While concern is common regarding depletion of ozone in the stratosphere, portions of the urban and rural United States periodically have high ambient levels of tropospheric ozone on the ground. Ozone pollution can cause a variety of impacts to susceptible vegetation (e.g., Ponderosa and Jeffrey pine species in the southwestern United States), such as stunted growth, alteration of growth form, needle or leaf chlorosis, and impaired ability to withstand drought-induced water stress. In addition, Southern Californian forests with high ozone exposures have been recently subject to multiyear droughts that have led to extensive forest overstory mortality from insect outbreaks and increased incidence of wildfires. Residual forests in these impacted areas may be more vulnerable to high ozone exposures and to other forest threats than ever before. NASA sensors collect a wealth of atmospheric data that have been used recently for mapping and monitoring regional tropospheric ozone levels. AIRS (Atmospheric Infrared Sounder), OMI (Ozone Monitoring Instrument), MLS (Microwave Limb Sounder), and TES (Tropospheric Emission Spectrometer) data could be used to assess forest ecosystem exposure to ozone. Such NASA data hold promise for providing better or at least complementary synoptic information on ground-level ozone levels that Federal agency partners can use to assess forest health trends and to mitigate the threats as needed in compliance with Federal laws and mandates. NASA data products on ozone concentrations may be able to aid applications of DSTs (decision support tools) adopted by the USDA FS (U.S. Department of Agriculture Forest Service) and by the NPS (National Park Service), such as the Ozone Calculator, in which ground ozone estimates are employed to assess ozone impacts to forested vegetation.

  14. Effects of long-term open-field ozone exposure on leaf phenolics of European silver birch (Betula pendula Roth).

    Saleem, A; Loponen, J; Pihlaja, K; Oksanen, E

    2001-05-01

    The response of phenolic compounds as a result of long-term low open-field ozone exposure was studied in ozone-sensitive and ozone-tolerant clones of European silver birch (Betula pendula Roth). The saplings were exposed to 1.5-1.6 times the ambient (elevated) ozone and ambient air (as control) over three growing seasons from May 1996 until August 1998. Quantification by modified Folin-Ciocalteau assay showed a 16.2% increase in total phenolics in elevated ozone plants as compared to that in controls and a corresponding 9.9% increase of 10 phenolic compounds quantified by HPLC. Five nonflavonoids and five flavonoids showed 8.4% and 11.4% increases, respectively. The phenolic results indicated slightly higher ozone sensitivity of clone 5 as compared to clone 2. The most ozone-responsive phenolic compounds in clone 2 and clone 5 were (+)-catechin (CT), chlorogenic acid (CGA), 5-p-coumaroylquinic acid (5CQA), 3-p-coumaroylquinic acid (3CQA), myricetin galactopyranoside (MG), quercetin-3-O-glucuronopyranoside (QGR), and quercetin-3-O-arabinofuranoside (QA). Increased phenolic content in ozone-exposed plants was related to impaired growth and accelerated leaf senescence, indicated by enhanced autumn leaf yellowing and lower chlorophyll and Mg content. The change in carbon allocation towards defensive phenolics at the expense of growth was greater in the ozone-sensitive clone as compared to tolerant clone. PMID:11471939

  15. Impacts of Ozone-vegetation Interactions and Biogeochemical Feedbacks on Atmospheric Composition and Air Quality Under Climate Change

    Sadeke, M.; Tai, A. P. K.; Lombardozzi, D.; Val Martin, M.

    2015-12-01

    Surface ozone pollution is one of the major environmental concerns due to its damaging effects on human and vegetation. One of the largest uncertainties of future surface ozone prediction comes from its interaction with vegetation under a changing climate. Ozone can be modulated by vegetation through, e.g., biogenic emissions, dry deposition and transpiration. These processes are in turn affected by chronic exposure to ozone via lowered photosynthesis rate and stomatal conductance. Both ozone and vegetation growth are expected to be altered by climate change. To better understand these climate-ozone-vegetation interactions and possible feedbacks on ozone itself via vegetation, we implement an online ozone-vegetation scheme [Lombardozzi et al., 2015] into the Community Earth System Model (CESM) with active atmospheric chemistry, climate and land surface components. Previous overestimation of surface ozone in eastern US, Canada and Europe is shown to be reduced by >8 ppb, reflecting improved model-observation comparison. Simulated surface ozone is lower by 3.7 ppb on average globally. Such reductions (and improvements) in simulated ozone are caused mainly by lower isoprene emission arising from reduced leaf area index in response to chronic ozone exposure. Effects via transpiration are also potentially significant but require better characterization. Such findings suggest that ozone-vegetation interaction may substantially alter future ozone simulations, especially under changing climate and ambient CO2 levels, which would further modulate ozone-vegetation interactions. Inclusion of such interactions in Earth system models is thus necessary to give more realistic estimation and prediction of surface ozone. This is crucial for better policy formulation regarding air quality, land use and climate change mitigation. Reference list: Lombardozzi, D., et al. "The Influence of Chronic Ozone Exposure on Global Carbon and Water Cycles." Journal of Climate 28.1 (2015): 292-305.

  16. Increased Growth Factors Play a Role in Wound Healing Promoted by Noninvasive Oxygen-Ozone Therapy in Diabetic Patients with Foot Ulcers

    Jing Zhang

    2014-01-01

    Full Text Available Management of diabetic foot ulcers (DFUs is a great challenge for clinicians. Although the oxygen-ozone treatment improves the diabetic outcome, there are few clinical trials to verify the efficacy and illuminate the underlying mechanisms of oxygen-ozone treatment on DFUs. In the present study, a total of 50 type 2 diabetic patients complicated with DFUs, Wagner stage 2~4, were randomized into control group treated by standard therapy only and ozone group treated by standard therapy plus oxygen-ozone treatment. The therapeutic effects were graded into 4 levels from grade 0 (no change to grade 3 (wound healing. The wound sizes were measured at baseline and day 20, respectively. Tissue biopsies were performed at baseline and day 11. The expressions of vascular endothelial growth factor (VEGF, transforming growth factor-β (TGF-β, and platelet-derived growth factor (PDGF proteins in the pathologic specimens were determined by immunohistochemical examinations. The effective rate of ozone group was significantly higher than that of control group (92% versus 64%, P<0.05. The wound size reduction was significantly more in ozone group than in control group (P<0.001. After treatment, the expressions of VEGF, TGF-β, and PDGF proteins at day 11 were significantly higher in ozone group than in control group. Ozone therapy promotes the wound healing of DFUs via potential induction of VEGF, TGF-β, and PDGF at early stage of the treatment. (Clinical trial registry number is ChiCTR-TRC-14004415.

  17. Long-term exposure to ambient ozone and mortality: a quantitative systematic review and meta-analysis of evidence from cohort studies

    Atkinson, Richard W.; Butland, Barbara K.; DIMITROULOPOULOU Chrysanthi; Heal, Mathew R.; Stedman, John R; Carslaw, Nicola; Jarvis, Deborah L; Heaviside, Clare; Vardoulakis, Sotiris; Walton, Heather; Anderson, H Ross

    2016-01-01

    Objectives While there is good evidence for associations between short-term exposure to ozone and a range of adverse health outcomes, the evidence from narrative reviews for long-term exposure is suggestive of associations with respiratory mortality only. We conducted a systematic, quantitative evaluation of the evidence from cohort studies, reporting associations between long-term exposure to ozone and mortality. Methods Cohort studies published in peer-reviewed journals indexed in EMBASE an...

  18. Long-term exposure to ambient ozone and mortality:A quantitative systematic review and meta-analysis of evidence from cohort studies

    Atkinson, R W; Butland, B K; Dimitroulopoulou, C.; Heal, M. R.; Stedman, J. R.; Carslaw, N.; Jarvis, D; Heaviside, C; Vardoulakis, S; Walton, H; Anderson, H R

    2016-01-01

    Objectives: While there is good evidence for associations between short-term exposure to ozone and a range of adverse health outcomes, the evidence from narrative reviews for long-term exposure is suggestive of associations with respiratory mortality only. We conducted a systematic, quantitative evaluation of the evidence from cohort studies, reporting associations between long-term exposure to ozone and mortality. Methods: Cohort studies published in peer-reviewed journals indexed in EMBASE ...

  19. Growth of lithium silicate crystals inside porous silicon film and their exploitation for ozone detection

    Ben Saad, K. [Centre de Recherches et des Technologies de l' Energie, Laboratoire de Nanomateriaux et des Systemes pour l' energie, BP 95, 2050 Hammam-Lif (Tunisia)], E-mail: BenSaadKhaled2005@yahoo.fr; Hamzaoui, H. [Centre de Recherches et des Technologies de l' Energie, Laboratoire des procedes chimique, BP 95, 2050 Hammam-Lif (Tunisia); Labidi, A. [Unite de Recherche de Physique des Semiconducteurs et Capteurs, IPEST, BP 51, La Marsa 2070, Tunis (Tunisia); Bessais, B. [Centre de Recherches et des Technologies de l' Energie, Laboratoire de Nanomateriaux et des Systemes pour l' energie, BP 95, 2050 Hammam-Lif (Tunisia)

    2008-04-30

    Silicon dioxide was formed by oxidizing porous silicon film and annealed, in a next step, at 920 deg. C with lithium nitrate embedded in its structure. These operations have produced the two lithium silicates, Li{sub 2}Si{sub 2}O{sub 5} and Li{sub 2}SiO{sub 3}, as it has been confirmed by the X-ray diffraction measurements. At relative high temperature (230 deg. C), the experimental ionic conductivity of this achieved sample has doubled in presence of ozone flow. A comparison with other samples, prepared with varieties of metallic nitrates and by following the same experimental procedures as for the former one, has proved that the sample prepared with zirconium was also good for ozone detection.

  20. Growth of lithium silicate crystals inside porous silicon film and their exploitation for ozone detection

    Silicon dioxide was formed by oxidizing porous silicon film and annealed, in a next step, at 920 deg. C with lithium nitrate embedded in its structure. These operations have produced the two lithium silicates, Li2Si2O5 and Li2SiO3, as it has been confirmed by the X-ray diffraction measurements. At relative high temperature (230 deg. C), the experimental ionic conductivity of this achieved sample has doubled in presence of ozone flow. A comparison with other samples, prepared with varieties of metallic nitrates and by following the same experimental procedures as for the former one, has proved that the sample prepared with zirconium was also good for ozone detection

  1. Measurement of Ozone Production Sensor

    M. Cazorla

    2010-05-01

    Full Text Available A new ambient air monitor, the Measurement of Ozone Production Sensor (MOPS, measures directly the rate of ozone production in the atmosphere. The sensor consists of two 11.3 L environmental chambers made of UV-transmitting Teflon film, a unit to convert NO2 to O3, and a modified ozone monitor. In the sample chamber, flowing ambient air is exposed to the sunlight so that ozone is produced just as it is in the atmosphere. In the second chamber, called the reference chamber, a UV-blocking film over the Teflon film prevents ozone formation but allows other processes to occur as they do in the sample chamber. The air flows that exit the two chambers are sampled by an ozone monitor operating in differential mode so that the difference between the two ozone signals, divided by the exposure time in the chambers, gives the ozone production rate. High-efficiency conversion of NO2 to O3 prior to detection in the ozone monitor accounts for differences in the NOx photostationary state that can occur in the two chambers. The MOPS measures the ozone production rate, but with the addition of NO to the sampled air flow, the MOPS can be used to study the sensitivity of ozone production to NO. Preliminary studies with the MOPS on the campus of the Pennsylvania State University show the potential of this new technique.

  2. Chronic drought stress reduced but not protected Shantung maple (Acer truncatum Bunge) from adverse effects of ozone (O3) on growth and physiology in the suburb of Beijing, China

    A two-year experiment exposing Acer truncatum Bunge seedlings to elevated ozone (O3) concentrations above ambient air (AO) and drought stress (DS) was carried out using open-top chambers (OTCs) in a suburb of Beijing in north China in 2012–2013. The results suggested that AO and DS had both significantly reduced leaf mass area (LMA), stomatal conductance (Gs), light saturated photosynthetic rate (Asat) as well as above and below ground biomass at the end of the experiment. It appeared that while drought stress mitigated the expression of foliar injury, LMA, leaf photosynthetic pigments, height growth and basal diameter, due to limited carbon fixation, the O3 – induced reductions in Asat, Gs and total biomass were enhanced 23.7%. 15.5% and 8.1% respectively. These data suggest that when the whole plant was considered that drought under the conditions of this experiment did not protect the Shantung maple seedlings from the effects of O3. - Highlights: • The response of Acer truncatum Bunge to drought and ozone was investigated. • Drought could mitigate the foliage injury and leaf photosynthetic pigments. • The O3-induced reductions in Asat, Gs and total biomass were enhanced by drought. - Drought didn't protect Shantung maple from O3 effects but rather cause more reductions in biomass

  3. The role of Si interstitials in the migration and growth of Ge nanocrystallites under thermal annealing in an oxidizing ambient

    Chen, Kuan-Hung; Wang, Ching-Chi; George, Tom; Li, Pei-Wen

    2014-01-01

    We report a unique growth and migration behavior of Ge nanocrystallites mediated by the presence of Si interstitials under thermal annealing at 900°C within an H2O ambient. The Ge nanocrystallites were previously generated by the selective oxidation of SiGe nanopillars and appeared to be very sensitive to the presence of Si interstitials that come either from adjacent Si3N4 layers or from within the oxidized nanopillars. A cooperative mechanism is proposed, wherein the Si interstitials aid in...

  4. Ambient-condition growth of high-pressure phase centrosymmetric crystalline KDP microstructures for optical second harmonic generation.

    Ren, Yan; Zhao, Xian; Hagley, Edward W; Deng, Lu

    2016-08-01

    Noncentrosymmetric potassium dihydrogen phosphate (KH2PO4 or KDP) in the tetragonal crystal phase is arguably the most extensively studied nonlinear optical crystal in history. It has prolific applications ranging from simple laser pointers to laser inertial confinement fusion systems. Recently, type IV high-pressure KDP crystal sheets with a monoclinic crystal phase having centrosymmetric properties have been observed. However, it was found that this new crystal phase is highly unstable under ambient conditions. We report ambient-condition growth of one-dimensional, self-assembled, single-crystalline KDP hexagonal hollow/solid-core microstructures that have a molecular structure and symmetry identical to the type IV KDP monoclinic crystal that was previously found to exist only at extremely high pressures (>1.6 GPa). Furthermore, we report highly efficient bulk optical second harmonic generation (SHG) from these ambient condition-grown single-crystalline microstructures, even though they have a highly centrosymmetric crystal phase. However, fundamental physics dictates that a bulk optical medium with a significant second-order nonlinear susceptibility supporting SHG must have noncentrosymmetric properties. Laue diffraction analysis reveals a weak symmetry-breaking twin-crystal lattice that, in conjunction with tight confinement of the light field by the tubular structure, is attributed to the significant SHG even with sample volumes <0.001 mm(3). A robust polarization-preserving effect is also observed, raising the possibility of advanced optical technological applications. PMID:27574703

  5. The Importance of Ambient Temperature to Growth and the Induction of Flowering.

    McClung, C R; Lou, Ping; Hermand, Victor; Kim, Jin A

    2016-01-01

    Plant development is exquisitely sensitive to the environment. Light quantity, quality, and duration (photoperiod) have profound effects on vegetative morphology and flowering time. Recent studies have demonstrated that ambient temperature is a similarly potent stimulus influencing morphology and flowering. In Arabidopsis, ambient temperatures that are high, but not so high as to induce a heat stress response, confer morphological changes that resemble the shade avoidance syndrome. Similarly, these high but not stressful temperatures can accelerate flowering under short day conditions as effectively as exposure to long days. Photoperiodic flowering entails a series of external coincidences, in which environmental cycles of light and dark must coincide with an internal cycle in gene expression established by the endogenous circadian clock. It is evident that a similar model of external coincidence applies to the effects of elevated ambient temperature on both vegetative morphology and the vegetative to reproductive transition. Further study is imperative, because global warming is predicted to have major effects on the performance and distribution of wild species and strong adverse effects on crop yields. It is critical to understand temperature perception and response at a mechanistic level and to integrate this knowledge with our understanding of other environmental responses, including biotic and abiotic stresses, in order to improve crop production sufficiently to sustainably feed an expanding world population. PMID:27602044

  6. Ambient ozone effects on gas exchange and total non-structural carbohydrate levels in cutleaf coneflower (Rudbeckia laciniata L.) growing in Great Smoky Mountains National Park

    Ozone-sensitive and -tolerant individuals of the perennial herbaceous cutleaf coneflower (Rudbeckia laciniata L.) were compared for their gas exchange characteristics and total non-structural carbohydrates in the Great Smoky Mountains National Park USA. Net photosynthesis decreased with increased f...

  7. Photochemical roles of rapid economic growth and potential abatement strategies on tropospheric ozone over South and East Asia in 2030

    S. Chatani

    2014-04-01

    Full Text Available A regional air quality simulation framework including the Weather Research and Forecasting modelling system (WRF, the Community Multi-scale Air Quality modeling system (CMAQ, and precursor emissions to simulate tropospheric ozone over South and East Asia is introduced. Concentrations of tropospheric ozone and related species simulated by the framework are validated by comparing with observation data of surface monitorings, ozone zondes, and satellites obtained in 2010. The simulation demonstrates acceptable performance on tropospheric ozone over South and East Asia at regional scale. Future energy consumption, carbon dioxide (CO2, nitrogen oxides (NOx, and volatile organic compound (VOC emissions in 2030 under three future scenarios are estimated. One of the scenarios assumes a business-as-usual (BAU pathway, and other two scenarios consider implementation of additional energy and environmental strategies to reduce energy consumption, CO2, NOx, and VOC emissions in China and India. Future surface ozone under these three scenarios is predicted by the simulation. The simulation indicates future surface ozone significantly increases around India for a whole year and around north eastern China in summer. NOx is a main driver on significant seasonal increase of surface ozone, whereas VOC as well as increasing background ozone and methane is also an important factor on annual average of surface ozone in East Asia. Warmer weather around India is also preferable for significant increase of surface ozone. Additional energy and environmental strategies assumed in future scenarios are expected to be effective to reduce future surface ozone over South and East Asia.

  8. Combination of U.V.-B and ozone reduces pollen tube growth more than either stress alone

    The rate of in vitro Nicotiana tabacum L. “Bel-W3” pollen tube growth was reduced 62 and 44%, respectively, when pollen tubes were exposed to 120 ppb ozone (O3) for 3 hr or 300 μW/cm2 ultraviolet-B (u.v.-B) radiation for 30 min. Petunia hybrida Vilm. “White Cascade” pollen tube growth was reduced 34 and 59%, respectively, upon exposure to O3 or u.v.-B at the above doses. The combination of u.v.-B at 300 μW/cm2 for 30 min, followed by O3 at 120 ppb for 3 hr, reduced pollen tube growth by 79% for “Bel-W3” and 75% for “White Cascade”. The effect appeared to be additive, implying that different target areas may be affected by the two stressors. In the Northeast, plants are exposed to both u.v.-B and O3 during the normal growing season. This may result in an unexpectedly higher stress on the reproductive system than had been previously suspected based on these two stressors acting individually. (author)

  9. 40 CFR 52.977 - Control strategy and regulations: Ozone.

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control strategy and regulations: Ozone... and regulations: Ozone. Determination of Attainment. Effective March 12, 2010 EPA has determined the Baton Rouge 1-hour ozone nonattainment area has attained the 1-hour ozone National Ambient Air...

  10. Hyaluronan Mediates Ozone-induced Airway Hyperresponsiveness in Mice*

    Garantziotis, Stavros; Li, Zhuowei; Potts, Erin N.; Kimata, Koji; Zhuo, Lisheng; Morgan, Daniel L.; Savani, Rashmin C.; Noble, Paul W.; Foster, W. Michael; Schwartz, David A; John W Hollingsworth

    2009-01-01

    Ozone is a common urban environmental air pollutant and significantly contributes to hospitalizations for respiratory illness. The mechanisms, which regulate ozone-induced bronchoconstriction, remain poorly understood. Hyaluronan was recently shown to play a central role in the response to noninfectious lung injury. Therefore, we hypothesized that hyaluronan contributes to airway hyperreactivity (AHR) after exposure to ambient ozone. Using an established model of ozone...

  11. Enhanced attached growth of microalgae Scenedesmus. LX1 through ambient bacterial pre-coating of cotton fiber carriers.

    Zhuang, Lin-Lan; Azimi, Yaldah; Yu, Dawei; Wang, Wen-Long; Wu, Yin-Hu; Dao, Guo-Hua; Hu, Hong-Ying

    2016-10-01

    The role of bacteria/extracellular polymeric substances (EPS) coated carriers on attached microalgae growth in suspended-solid phase photobioreactor (sspBR) was assessed in this study. The results showed that pre-coating cotton with ambient bacteria and their EPS improved the attached microalgal growth by as much as 230% in terms of attached microalgae density. Additionally, the single cell dry weight, chemical composition and oxygen evolving activity of attached microalgae were significantly affected by the presence of bacteria/EPS coating on the cotton carriers. The protein content of microalgae cells cultivated in the ssPBRs with carriers coated by bacteria and sterilized bacteria were on average 26% and 15% more than uncoated carriers, respectively. Through absorbing and immobilizing nutrients from the bulk medium, the bacteria/EPS coating provided the attached microalgae with nitrogen/phosphorus for protein synthesis, especially during the late stages of batch cultivation. PMID:27416514

  12. Final report, on-going key comparison BIPM.QM-K1: ozone at ambient level, comparison with DMDM, July 2015

    Viallon, J.; Moussay, P.; Wielgosz, R.; Bebic, J.; Norris, J. E.; Guenther, F.

    2016-01-01

    As part of the on-going key comparison BIPM.QM-K1, a comparison has been performed between the ozone national standard of the Directorate of Measures and Precious Metals (DMDM) and the common reference standard of the key comparison, maintained by the Bureau International des Poids et Mesures (BIPM), via a transfer standard maintained by the National Institute of Standards and Technology (NIST). The instruments have been compared over a nominal ozone amount-of-substance fraction range of 0 nmol/mol to 500 nmol/mol Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  13. Photochemical roles of rapid economic growth and potential abatement strategies on tropospheric ozone over South and East Asia in 2030

    Chatani, S.; Amann, M.; Goel, A.; Hao, J.; Klimont, Z.; Kumar, A.; Mishra, A.; Sharma, S.; Wang, S. X.; Wang, Y. X.; Zhao, B.

    2014-09-01

    A regional air quality simulation framework including the Weather Research and Forecasting modeling system (WRF), the Community Multi-scale Air Quality modeling system (CMAQ), and precursor emissions to simulate tropospheric ozone over South and East Asia is introduced. Concentrations of tropospheric ozone and related species simulated by the framework are validated by comparing with observation data of surface monitoring, ozonesondes, and satellites obtained in 2010. The simulation demonstrates acceptable performance on tropospheric ozone over South and East Asia at regional scale. Future energy consumption, carbon dioxide (CO2), nitrogen oxides (NOx), and volatile organic compound (VOC) emissions in 2030 under three future scenarios are estimated. One of the scenarios assumes a business-as-usual (BAU) pathway, and other two scenarios consider implementation of additional energy and environmental strategies to reduce energy consumption, CO2, NOx, and VOC emissions in China and India. Future surface ozone under these three scenarios is predicted by the simulation. The simulation indicates future surface ozone significantly increases around India for a whole year and around northeastern China in summer. NOx is a main driver on significant seasonal increase of surface ozone, whereas VOC as well as increasing background ozone and methane is also an important factor on annual average of surface ozone in East Asia. Warmer weather around India is also preferable for significant increase of surface ozone. Additional energy and environmental strategies assumed in future scenarios are expected to be effective to reduce future surface ozone over South and East Asia.

  14. Ozone exposure of a weed community produces adaptive changes in seed populations of Spergula arvensis.

    Jennifer B Landesmann

    Full Text Available Tropospheric ozone is one of the major drivers of global change. This stress factor alters plant growth and development. Ozone could act as a selection pressure on species communities composition, but also on population genetic background, thus affecting life history traits. Our objective was to evaluate the consequences of prolonged ozone exposure of a weed community on phenotypic traits of Spergulaarvensis linked to persistence. Specifically, we predicted that the selection pressure exerted by high ozone concentrations as well as the concomitant changes in the weed community would drive population adaptive changes which will be reflected on seed germination, dormancy and longevity. In order to test seed viability and dormancy level, we conducted germination experiments for which we used seeds produced by S. arvensis plants grown within a weed community exposed to three ozone treatments during four years (0, 90 and 120 ppb. We also performed a soil seed bank experiment to test seed longevity with seeds coming from both the four-year ozone exposure experiment and from a short-term treatment conducted at ambient and added ozone concentrations. We found that prolonged ozone exposure produced changes in seed germination, dormancy and longevity, resulting in three S. arvensis populations. Seeds from the 90 ppb ozone selection treatment had the highest level of germination when stored at 75% RH and 25 °C and then scarified. These seeds showed the lowest dormancy level when being subjected to 5 ºC/5% RH and 25 ºC/75% followed by 5% RH storage conditions. Furthermore, ozone exposure increased seed persistence in the soil through a maternal effect. Given that tropospheric ozone is an important pollutant in rural areas, changes in seed traits due to ozone exposure could increase weed persistence in fields, thus affecting weed-crop interactions, which could ultimately reduce crop production.

  15. Photochemical roles of rapid economic growth and potential abatement strategies on tropospheric ozone over South and East Asia in 2030

    S. Chatani; M. Amann; Goel, A.; J. Hao; Z. Klimont; Kumar, A.; Mishra, A.; S Sharma; Wang, S. X.; Wang, Y. X.; B. Zhao

    2014-01-01

    A regional air quality simulation framework including the Weather Research and Forecasting modelling system (WRF), the Community Multi-scale Air Quality modeling system (CMAQ), and precursor emissions to simulate tropospheric ozone over South and East Asia is introduced. Concentrations of tropospheric ozone and related species simulated by the framework are validated by comparing with observation data of surface monitorings, ozone zondes, and satellites obt...

  16. Corona Discharge Influences Ozone Concentrations Near Rats

    Goheen, Steven C.; Gaither, Kari A.; Anantatmula, Shantha M.; Mong, Gary M.; Sasser, Lyle B.; Lessor, Delbert L.

    2004-02-26

    Ozone is produced by corona discharge in air. Its production is enhanced near grounded water. Whether grounded animals behave like grounded water, producing more ozone was investigated. Rats were exposed to corona discharge in a plastic cage. The concentration of ozone in the gas phase was monitored. The ozone concentration exceeded ambient levels only in the presence of corona discharge and either rats or water. When water or rats were exposed to corona discharge, ozone levels were more than 10 times higher than controls. Ozone levels increased rapidly with applied voltage. There was also a correlation between the distance of the corona needle to the rats and the amount of ozone produced. As the distance increased, ozone production decreased. These results are discussed in relation to the potential exposure of mammals to ozone in the vicinity of corona discharge and electric fields.

  17. Growth of YBa2(Cu, Co)4O8 single crystals under ambient pressure and their superconducting properties

    We report the growth of superconducting YBa2(Cu, Co)4O8 single crystals using KOH flux under ambient pressure and their superconducting properties. The average size of the YBa2(Cu, Co)4O8 single crystals is 0.3 x 0.3 x 0.2 mm3. The superconducting transition temperature (Tc) of the parent material is found to be 81 K, indicating a stoichiometric oxide superconductor. The Tc and the c-axis length of YBa2(Cu, Co)4O8 single crystals decrease systematically with increasing the Co-doping content. A comparison of the magnetic irreversibility with the flux-creep theory from the viewpoint of homogeneity/inhomogeneity is made. (author)

  18. Multi-morphological growth of nano-structured In2Se3 by ambient pressure triethylene glycol based solution syntheses

    In2Se3 nanoparticles, flower-like shaped and sheet-shaped nanocrystals were synthesized by a new, facile, ambient pressure triethylene glycol based solution chemical route using indium(III) chloride and selenium powder as precursors. The growing morphology, crystallization, chemical stoichiometry and light absorption property of the In2Se3 products synthesized were characterized by TEM, HRTEM, FESEM, XRD, EDX and UV–vis–NIR measurements. Multi-morphological growth of the nano-structured In2Se3 in triethylene glycol based solution syntheses with changed assisting agents and reaction styles was demonstrated. - Highlights: • Multimorphological growth of In2Se3 was demonstrated based on solution chemistry. • A new, facile, low cost and fast air pressure TEG based solution process was used. • Nanoparticles, flower-like shaped and sheet-shaped nanocrystals were synthesized. • Morphology, crystallization, stoichiometry and light absorption was characterized. • Solution growth of β-In2Se3 nanosheets was firstly reported by this submission

  19. Effects of SO2 oxidation on ambient aerosol growth in water and ethanol vapours

    A. Laaksonen

    2004-11-01

    Full Text Available Hygroscopicity (i.e. water vapour affinity of atmospheric aerosol particles is one of the key factors in defining their impacts on climate. Condensation of sulphuric acid onto less hygroscopic particles is expected to increase their hygrocopicity and hence their cloud condensation nuclei formation potential. In this study, differences in the hygroscopic and ethanol uptake properties of ultrafine aerosol particles in the Arctic air masses with a different exposure to anthropogenic sulfur pollution were examined. The main discovery was that Aitken mode particles having been exposed to polluted air were more hygroscopic and less soluble to ethanol than after transport in clean air. This aging process was attributed to sulfur dioxide oxidation and subsequent condensation during the transport of these particle to our measurement site. The hygroscopicity of nucleation mode aerosol particles, on the other hand, was approximately the same in all the cases, being indicative of a relatively similar chemical composition despite the differences in air mass transport routes. These particles had also been produced closer to the observation site typically 3–8 h prior to sampling. Apparently, these particles did not have an opportunity to accumulate sulphuric acid on their way to the site, but instead their chemical composition (hygroscopicity and ethanol solubility resembled that of particles produced in the local or semi-regional ambient conditions.

  20. Impact of Experimentally Elevated Ozone on Seed Germination and Growth of Russian Pine (Pinus sylvestris) and Spruce (Picea spp.) Provenances

    Prozherina, Nadezda; Nakvasina, Elena; Oksanen, Elina

    2009-01-01

    The impact of elevated ozone concentrations on early ontogenetic stages of pine (Pinus sylvestris) and spruce (Picea abies, Picea obovata, P. abies X P. obovata) seedlings originating from different provenances in Russia were studied in the open-field ozone fumigation system located in Kuopio, Finla

  1. Ambient levels and temporal trends of VOCs, including carbonyl compounds, and ozone at Cabañeros National Park border, Spain

    Villanueva, Florentina; Tapia, Araceli; Notario, Alberto; Albaladejo, José; Martínez, Ernesto

    2014-03-01

    Concentration levels of 15 carbonyls, 17 VOCs and ozone were studied at Cabañeros National Park border, Spain, in an area mainly constituted by holm oaks (Quercus ilex) and cork oaks (Quercus suber), along with scrubland formations such as rock-rose and heather. The compounds were collected by means of diffusive samplers from August-November 2010 and February-August 2011. Carbonyl compounds, VOCs and O3 were analysed by HPLC with diode array UV-Vis detector, GC-FID and by UV-visible spectrophotometry, respectively. The most abundant carbonyls were hexanal, acetone-acrolein, formaldehyde and acetaldehyde. Seasonal variation was apparent with maximum values observed in summer months. Total carbonyl concentrations ranged from 2.8 to 19.7 μg m-3. Most VOCs studied (using chemically desorbable cartridges) were either not detected or were below their detection limits, however, a parallel sampling using thermally desorbable cartridges, from May 22 to June 19, revealed the presence of much more VOCs, identified using GC-MS. O3 concentration ranged from 27.2 to 90.5 μg m-3, reaching the maximum monthly mean concentration in March (84.4 μg m-3). The analysis of back trajectories indicates the transport of polluted air masses from remote areas, mainly from the Mediterranean basin that should contribute to the high levels of ozone observed.

  2. An exploratory analysis of the relationship between ambient ozone and particulate matter concentrations during early pregnancy and selected birth defects in Texas

    We performed an exploratory analysis of ozone (O3) and fine particulate matter (PM2.5) concentrations during early pregnancy and multiple types of birth defects. Data on births were obtained from the Texas Birth Defects Registry (TBDR) and the National Birth Defects Prevention Study (NBDPS) in Texas. Air pollution concentrations were previously determined by combining modeled air pollution concentrations with air monitoring data. The analysis generated hypotheses for future, confirmatory studies; although many of the observed associations were null. The hypotheses are provided by an observed association between O3 and craniosynostosis and inverse associations between PM2.5 and septal and obstructive heart defects in the TBDR. Associations with PM2.5 for septal heart defects and ventricular outflow tract obstructions were null using the NBDPS. Both the TBDR and the NBPDS had inverse associations between O3 and septal heart defects. Further research to confirm the observed associations is warranted. - Highlights: • Air pollution concentrations combined modeled air data and air monitoring data. • No associations were observed between the majority of birth defects and PM2.5 and O3. • Estimated associations between PM2.5 and certain heart defects varied by dataset. • Results were suggestive of an inverse association between O3 and septal heart defects. • Higher O3 concentrations may be associated with increased odds of craniosynostosis. - Although most observed associations between ozone and fine particulate matter concentrations and birth defects were null, some were present and warrant further consideration

  3. Short-term UV-B radiation and ozone exposure effects on aromatic secondary metabolite accumulation and shoot growth of flavonoid-deficient Arabidopsis mutants

    The presence of UV-absorptive substances in the epidermal cells of leaves is thought to protect mesophyll tissues from the harmful effects of UV-B radiation. We examined the influence of short-term UV-B exposures on UV-absorptive (330 nm) sinapates and flavonols, and on shoot growth of the Arabidopsis wild type ecotype Landsberg erecta and two mutants. 114 deficient in chalcone synthase, and 115, deficient in chalcone/flavonone isomerase. Sequential ozone exposures were used to determine the effects of oxidative stress The levels of sinapates and flavonols on a leaf fresh weight basis increased substantially in the wild type and sinapates increased in the 114 mutant in vegetative vegetative/reproductive transitional and reproductive stage plants in response to short-term (48h) UV-B radiation. When UV-B was discontinued the levels generally decreased lo pre-exposure levels after 48 h in vegetative/reproductive but not in reproductive plants. Exposure to ozone before or alter UV-B treatment did not consistently affect the levels of these UV-absorptive compounds. Dry matter accumulation was less affected by UV-B at the vegetative and reproductive stages than at the vegetative/reproductive stage. At the vegetative/reproductive stage, shoot growth of all 3 genotypes was retarded by UV-B. Growth was not retarded by short-term ozone exposure alone but when exposure to ozone followed UV-B exposure, growth was reduced in all genotypes. Leaf cupping appeared on 115 plants exposed to UV-B

  4. A review of the literature on the effects of ambient air pollution on fetal growth

    A systematic review of the literature on the effects of air pollution on low birth weight (LBW) and its determinants, preterm delivery (PTD) and intrauterine growth restriction (IUGR), was conducted. Twelve epidemiologic investigations that addressed the impact of air pollution on four pregnancy outcomes were identified. Results were analyzed separately for each perinatal outcome because of differences in pathogenic mechanisms. Effects of air pollution were apparent on PTD and IUGR, but not on LBW. Most of the associations reported were rather small. The estimation of summary effects was not meaningful because of the heterogeneity of the effect estimates arising from differences in the measurements of outcome, exposure, and confounders and the small number of studies per outcome (four studies for PTD and six for IUGR). Current scientific knowledge on the impact of air pollution on fetal growth is still limited; thus, several issues should be examined further

  5. Elevated atmospheric carbon dioxide and ozone concentrations alter LAI through changes in phenology and leaf growth

    Leaves are critical for harvesting light energy, taking up carbon dioxide (CO2) and transpiring water for cooling. Changes in leaf growth, expansion or development can integrate across the plant canopy and growing season to significantly impact productivity, yield and plant-atmosphere fluxes. Althou...

  6. 环境空气中臭氧API评价探讨%Study on Air Ozone API Evaluation

    徐建平

    2012-01-01

    Air ozone API evaluation is considered that area of influence on ozone concentration exceed ambient air quality, ozone API correction on hours on ozone concentration exceed ambient air quality and Ozone average concentration exceed ambient air quality.%环境空气中臭氧API评价应考虑臭氧超标影响范围、臭氧超标小时数和超标平均浓度对臭氧API修正.

  7. Modeling of Stomatal Conductance for Estimating Ozone Uptake of Fagus crenata Under Experimentally Enhanced Free-air Ozone Exposure

    Hoshika, Yasutomo; Watanabe, Makoto; Inada, Naoki; KOIKE, Takayoshi

    2012-01-01

    We examined a performance of the multiplicative stomatal conductance model to estimate the stomatal ozone uptake for Fagus crenata. Parameterization of the model was carried out by in-situ measurements in a free-air ozone exposure experiment. The model performed fairly well under ambient conditions, with low ozone concentration. However, the model overestimated stomatal conductance under enhanced ozone condition due to ozone-induced stomatal closure. A revised model that included a parameter ...

  8. Effects of Ambient Humidity on Plant Growth Enhancement by Atmospheric Air Plasma Irradiation to Plant Seeds

    Sarinont, Thapanut; Amano, Takaaki; Koga, Kazunori; Shiratani, Masaharu

    2015-09-01

    Humidity is an important factor for plasma-bio applications because composition of species generated by atmospheric pressure plasmas significantly depends on the humidity. Here we have examined effects of humidity on the growth enhancement to study the mechanism. Experiments were carried out with a scalable DBD device. 10 seeds of Raphanus sativus L. were set for x = 5 mm and y = 3 mm below the electrodes. The humidity Hair was 10 - 90 %Rh. The ratio of length of plants with plasma irradiation to that of control increases from 1.2 for Hair = 10 %Rh to 2.5 for Hair = 50 %Rh. The ratio is 2.5 for Hair = 50-90 %Rh. This humidity dependence is similar to the humidity dependence of O2+-H2O,H3O*, NO2--H2Oand NO3--H2Odensities, whereas it is different from that of other species such as O3, NO, and so on. The similarity gives information on key species for the growth enhancement.

  9. Exposure-Relevant Ozone Chemistry in Occupied Spaces

    Coleman, Beverly Kaye [Univ. of California, Berkeley, CA (United States)

    2009-04-01

    Ozone, an ambient pollutant, is transformed into other airborne pollutants in the indoor environment. In this dissertation, the type and amount of byproducts that result from ozone reactions with common indoor surfaces, surface residues, and vapors were determined, pollutant concentrations were related to occupant exposure, and frameworks were developed to predict byproduct concentrations under various indoor conditions. In Chapter 2, an analysis is presented of secondary organic aerosol formation from the reaction of ozone with gas-phase, terpene-containing consumer products in small chamber experiments under conditions relevant for residential and commercial buildings. The full particle size distribution was continuously monitored, and ultrafine and fine particle concentrations were in the range of 10 to>300 mu g m-3. Particle nucleation and growth dynamics were characterized.Chapter 3 presents an investigation of ozone reactions with aircraft cabin surfaces including carpet, seat fabric, plastics, and laundered and worn clothing fabric. Small chamber experiments were used to determine ozone deposition velocities, ozone reaction probabilities, byproduct emission rates, and byproduct yields for each surface category. The most commonly detected byproducts included C1?C10 saturated aldehydes and skin oil oxidation products. For all materials, emission rates were higher with ozone than without. Experimental results were used to predict byproduct exposure in the cabin and compare to other environments. Byproduct levels are predicted to be similar to ozone levels in the cabin, which have been found to be tens to low hundreds of ppb in the absence of an ozone converter. In Chapter 4, a model is presented that predicts ozone uptake by and byproduct emission from residual chemicals on surfaces. The effects of input parameters (residue surface concentration, ozone concentration, reactivity of the residue and the surface, near-surface airflow conditions, and

  10. Effects of ozone on growth, net photosynthesis and yield of two African varieties of Vigna unguiculata.

    Tetteh, Rashied; Yamaguchi, Masahiro; Wada, Yoshiharu; Funada, Ryo; Izuta, Takeshi

    2015-01-01

    To assess the effects of O(3)on growth, net photosynthesis and yield of two African varieties of cowpea(Vigna unguiculata L.), Blackeye and Asontem were exposed as potted plants to air that was either filtered to remove O(3) (FA), non-filtered air (NF), non-filtered with added O3 of approximately 50 nL L(-1) (ppb) from 11:00 to 16:00 (NF + O(3)) for 88 days in open-top chambers. The mean O(3) concentration (11:00-16:00) during the exposure period had a range from 16 ppb in the FA treatment to 118 ppb in the NF + O(3) treatment. Net photosynthetic rate and leaf area per plant were significantly reduced by exposure to O(3), reducing the growth of both varieties. Exposure to O(3) significantly reduced the 100-seed weight and number of seeds per pod. As a result, cowpea yield was significantly reduced by long-term exposure to O(3), with no difference in sensitivity between the varieties. PMID:25463718

  11. Photochemical roles of rapid economic growth and potential abatement strategies on tropospheric ozone over South and East Asia in 2030

    S. Chatani; M. Amann; Goel, A.; J. Hao; Z. Klimont; Kumar, A.; Mishra, A.; S Sharma; Wang, S. X.; Wang, Y. X.; B. Zhao

    2014-01-01

    A regional air quality simulation framework including the Weather Research and Forecasting modeling system (WRF), the Community Multi-scale Air Quality modeling system (CMAQ), and precursor emissions to simulate tropospheric ozone over South and East Asia is introduced. Concentrations of tropospheric ozone and related species simulated by the framework are validated by comparing with observation data of surface monitoring, ozonesondes, and satellites obtained in 2010. The simul...

  12. In situ laser ablation plasma diagnostics in the film growth regime: Effects of ambient background gases

    The propagation of the laser-induced plasma formed by KrF irradiation of Y1Ba2Cu3O7 has been characterized in background pressures of oxygen and argon typically used for thin film growth. The ion current transmitted through the background gases was recorded along the normal to the irradiated pellet as a function of distance in order to measure the decreasing velocity and magnitude of the expanding plasma current due to collisional slowing and attenuation of the laser plume. The integrated ion charge delivered to a substrate at low pressures can be described by elastic scattering giving a general integral cross sections of σe[O2] = 3.2 x 10-16 cm2 and σe[Ar] = 2.7 x 10-16 cm2. At higher pressures, inelastic scattering leads to increased recombination and reactive conversion of ions indicated by increased fluorescence of all the species, which becomes dominated by fluorescence of YO and BaO. Spatially resolved fluorescence measurements indicate that the luminous boundary to the plasma follows a weak shock front which coincides with the ion flux propagation. The ion transmission is found to drop exponentially with distance and background pressure, in agreement with a simple scattering model which yields general scattering cross sections for ion-argon σi-Ar = 2.1 x 10-16 cm2 and ion-oxygen σi-O2 = 2.3 x 10-16 cm2 interactions in background pressures up to 300 mTorr. The general features of the plume deceleration are described in terms of a drag force model. 9 refs., 5 figs

  13. Use of the antiozonant ethylenediurea (EDU) in Italy: Verification of the effects of ambient ozone on crop plants and trees and investigation of EDU's mode of action

    Paoletti, Elena, E-mail: e.paoletti@ipp.cnr.i [IPP-CNR, Via Madonna del Piano 10, I-50019 Sesto Fiorentino, Florence (Italy); Contran, Nicla [Department of Biotechnology and Biology, University of Milano-Bicocca, Piazza della Scienza 1, Milan (Italy); Manning, William J. [Department of Plant, Soil and Insect Sciences, University of Massachusetts, Amherst, MA 01003-9320 (United States); Ferrara, Anna M. [IPLA, Corso Casale 476, I-10128 Turin (Italy)

    2009-05-15

    Twenty-four experiments where EDU was used to protect plants from ozone (O{sub 3}) in Italy are reviewed. Doses of 150 and 450 ppm EDU at 2-3 week intervals were successfully applied to alleviate O{sub 3}-caused visible injury and growth reductions in crop and forest species respectively. EDU was mainly applied as soil drench to crops and by stem injection or infusion into trees. Visible injury was delayed and reduced but not completely. In investigations on mode of action, EDU was quickly (<2 h) uptaken and translocated to the leaf apoplast where it persisted long (>8 days), as it cannot move via phloem. EDU did not enter cells, suggesting it does not directly affect cell metabolism. EDU delayed senescence, did not affect photosynthesis and foliar nitrogen content, and stimulated antioxidant responses to O{sub 3} exposure. Preliminary results suggest developing an effective soil application method for forest trees is warranted. - EDU was successful as a tool in determining ozone effects on vegetation in Italy, but while progress was made, its mode of action remains unresolved.

  14. Effect of Different Arbuscular Mycorrhizal Fungi on Growth and Physiology of Maize at Ambient and Low Temperature Regimes

    Xiaoying Chen

    2014-01-01

    Full Text Available The effect of four different arbuscular mycorrhizal fungi (AMF on the growth and lipid peroxidation, soluble sugar, proline contents, and antioxidant enzymes activities of Zea mays L. was studied in pot culture subjected to two temperature regimes. Maize plants were grown in pots filled with a mixture of sandy and black soil for 5 weeks, and then half of the plants were exposed to low temperature for 1 week while the rest of the plants were grown under ambient temperature and severed as control. Different AMF resulted in different root colonization and low temperature significantly decreased AM colonization. Low temperature remarkably decreased plant height and total dry weight but increased root dry weight and root-shoot ratio. The AM plants had higher proline content compared with the non-AM plants. The maize plants inoculated with Glomus etunicatum and G. intraradices had higher malondialdehyde and soluble sugar contents under low temperature condition. The activities of catalase (CAT and peroxidase of AM inoculated maize were higher than those of non-AM ones. Low temperature noticeably decreased the activities of CAT. The results suggest that low temperature adversely affects maize physiology and AM symbiosis can improve maize seedlings tolerance to low temperature stress.

  15. Ozone dose-response relationships for spring oilseed rape and broccoli

    De Bock, Maarten; Op de Beeck, Maarten; De Temmerman, Ludwig; Guisez, Yves; Ceulemans, Reinhart; Vandermeiren, Karine

    2011-03-01

    Tropospheric ozone is an important air pollutant with known detrimental effects for several crops. Ozone effects on seed yield, oil percentage, oil yield and 1000 seed weight were examined for spring oilseed rape ( Brassica napus cv. Ability). For broccoli ( Brassica oleracea L. cv. Italica cv. Monaco) the effects on fresh marketable weight and total dry weight were studied. Current ozone levels were compared with an increase of 20 and 40 ppb during 8 h per day, over the entire growing season. Oilseed rape seed yield was negatively correlated with ozone dose indices calculated from emergence until harvest. This resulted in an R2 of 0.24 and 0.26 ( p rape. The reduction of oilseed rape yield showed the highest correlation with the ozone uptake during the vegetative growth stage: when only the first 47 days after emergence were used to calculate POD 6, R2 values increased up to 0.476 or even 0.545 when the first 23 days were excluded. The highest ozone treatments, corresponding to the future ambient level by 2100 (IPCC, Meehl et al., 2007), led to a reduction of approximately 30% in oilseed rape seed yield in comparison to the current ozone concentrations. Oil percentage was also significantly reduced in response to ozone ( p < 0.001). As a consequence oil yield was even more severely affected by elevated ozone exposure compared to seed yield: critical levels for oil yield dropped to 3.2 ppm h and 3.9 mmol m -2. For broccoli the applied ozone doses had no effect on yield.

  16. Effects of ozone on growth, yield and leaf gas exchange rates of two Bangladeshi cultivars of wheat (Triticum aestivum L.).

    Akhtar, Nahid; Yamaguchi, Masahiro; Inada, Hidetoshi; Hoshino, Daiki; Kondo, Taisuke; Izuta, Takeshi

    2010-05-01

    To clarify the effects of O(3) on crop plants cultivated in Bangladesh, two Bangladeshi wheat cultivars (Sufi and Bijoy) were grown in plastic boxes filled with Andisol and exposed daily to charcoal-filtered air or O(3) at 60 and 100 nl l(-1) (10:00-17:00) from 13 March to 4 June 2008. The whole-plant dry mass and grain yield per plant of the two cultivars at the final harvest were significantly reduced by the exposure to O(3). Although there was no significant effect of O(3) on stomatal diffusive conductance to H(2)O of flag leaf, net photosynthetic rate of the leaf was significantly reduced by the exposure to O(3.) The sensitivity of growth, yield, yield components and leaf gas exchange rates to O(3) was not significantly different between the two cultivars. The results obtained in the present study suggest that ambient levels of O(3) may detrimentally affect wheat production in Bangladesh. PMID:19962222

  17. Effects of elevated ozone on growth and yield of field-grown rice in Yangtze River Delta,China

    CHEN Zhan; WANG Xiaoke; FENG Zhaozhong; ZHENG Feixiang; DUAN Xiaonan; YANG Wenrui

    2008-01-01

    With rapid industrialization and urbanization in the Yangtze Delta,China,the tropospheric ozone concentration has increased to levels that induce orop yield loss.Rice,a widely grown crop in China,was investigated in field-established,open-top chambers.Four treatments were used:charcoal-filtered air (CF),non-charcoal-filtered air (NF),and charcoal-filtered air with two levels of additional ozone (O3-1 and O3-2).The AOT40s (accumulated hourly mean ozone concentration above 40 ppbv) were 0,0.91,23.24,and 39.28 ppmv.h for treatraent of CF,NF,O3-1,and O3-2,respectively.The rice height and biomass were reduced in the elevated ozone concentration.Less organic matter partitioning to roots under the elevated ozone significantly decreased rice root activity.The yield loss was 14.3% and 20.2% under O3-1 and O3-2 exposure,respectively.This was largely caused by a reduction in grain weight per panicle.

  18. Growth behavior and properties of atomic layer deposited tin oxide on silicon from novel tin(II)acetylacetonate precursor and ozone

    In this work, a novel liquid tin(II) precursor, tin(II)acetylacetonate [Sn(acac)2], was used to deposit tin oxide films on Si(100) substrate, using a custom-built hot wall atomic layer deposition (ALD) reactor. Three different oxidizers, water, oxygen, and ozone, were tried. Resulting growth rates were studied as a function of precursor dosage, oxidizer dosage, reactor temperature, and number of ALD cycles. The film growth rate was found to be 0.1 ± 0.01 nm/cycle within the wide ALD temperature window of 175–300 °C using ozone; no film growth was observed with water or oxygen. Characterization methods were used to study the composition, interface quality, crystallinity, microstructure, refractive index, surface morphology, and resistivity of the resulting films. X-ray photoelectron spectra showed the formation of a clean SnOx–Si interface. The resistivity of the SnOx films was calculated to be 0.3 Ω cm. Results of this work demonstrate the possibility of introducing Sn(acac)2 as tin precursor to deposit conducting ALD SnOx thin films on a silicon surface, with clean interface and no formation of undesired SiO2 or other interfacial reaction products, for transparent conducting oxide applications

  19. Ambient Air Pollution and Birth Weight in Full-Term Infants in Atlanta, 1994–2004

    Darrow, Lyndsey A.; Klein, Mitchel; Strickland, Matthew J; Mulholland, James A.; Tolbert, Paige E.

    2010-01-01

    Background An emerging body of evidence suggests that ambient levels of air pollution during pregnancy are associated with fetal growth. Objectives We examined relationships between birth weight and temporal variation in ambient levels of carbon monoxide, nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone, particulate matter ≤ 10 μm in diameter (PM10), ≤ 2.5 μm (PM2.5), 2.5 to 10 μm (PM2.5–10), and PM2.5 chemical component measurements for 406,627 full-term births occurring between 1994 and ...

  20. Plant Species Sensitivity Distributions for ozone exposure

    This study derived Species Sensitivity Distributions (SSD), representing a cumulative stressor-response distribution based on single-species sensitivity data, for ozone exposure on natural vegetation. SSDs were constructed for three species groups, i.e. trees, annual grassland and perennial grassland species, using species-specific exposure–response data. The SSDs were applied in two ways. First, critical levels were calculated for each species group and compared to current critical levels for ozone exposure. Second, spatially explicit estimates of the potentially affected fraction of plant species in Northwestern Europe were calculated, based on ambient ozone concentrations. We found that the SSD-based critical levels were lower than for the current critical levels for ozone exposure, with conventional critical levels for ozone relating to 8–20% affected plant species. Our study shows that the SSD concept can be successfully applied to both derive critical ozone levels and estimate the potentially affected species fraction of plant communities along specific ozone gradients. -- Highlights: ► Plant Species Sensitivity Distributions were derived for ozone exposure. ► Annual grassland species, as a species assemblage, tend to be most sensitive to ozone. ► Conventional critical levels for ozone relate to 8–20% affected plant species. ► The affected fraction of plant species for current ozone exposure in Northwestern Europe is estimated. -- Species Sensitivity Distributions offer opportunities in ozone risk assessment to both derive critical levels and estimate the affected fraction of a plant community

  1. Modeling the effect of temperature on ozone-related mortality

    Wilson, Ander; Rappold, Ana G.; Neas, Lucas M.; Reich, Brian J.

    2014-01-01

    Climate change is expected to alter the distribution of ambient ozone levels and temperatures which, in turn, may impact public health. Much research has focused on the effect of short-term ozone exposures on mortality and morbidity while controlling for temperature as a confounder, but less is known about the joint effects of ozone and temperature. The extent of the health effects of changing ozone levels and temperatures will depend on whether these effects are additive or synergistic. In t...

  2. Influence of Feeding Enzymatically Hydrolyzed Yeast Cell Wall on Growth Performance and Digestive Function of Feedlot Cattle during Periods of Elevated Ambient Temperature

    Salinas-Chavira, J.; Arzola, C.; González-Vizcarra, V.; Manríquez-Núñez, O. M.; Montaño-Gómez, M. F.; Navarrete-Reyes, J. D.; Raymundo, C.; Zinn, R. A.

    2015-01-01

    In experiment 1, eighty crossbred steers (239±15 kg) were used in a 229-d experiment to evaluate the effects of increasing levels of enzymatically hydrolyzed yeast (EHY) cell wall in diets on growth performance feedlot cattle during periods of elevated ambient temperature. Treatments consisted of steam-flaked corn-based diets supplemented to provide 0, 1, 2, or 3 g EHY/hd/d. There were no effects on growth performance during the initial 139-d period. However, from d 139 to harvest, when 24-h ...

  3. Protection of ash (Fraxinus excelsior) trees from ozone injury by ethylenediurea (EDU): Roles of biochemical changes and decreased stomatal conductance in enhancement of growth

    Treatments with ethylenediurea (EDU) protect plants from ozone foliar injury, but the processes underlying this protection are poorly understood. Adult ash trees (Fraxinus excelsior), with or without foliar ozone symptoms in previous years, were treated with EDU at 450 ppm by gravitational trunk infusion in May-September 2005 (32.5 ppm h AOT40). At 30-day intervals, shoot growth, gas exchange, chlorophyll a fluorescence, and water potential were determined. In September, several biochemical parameters were measured. The protective influence of EDU was supported by enhancement in the number of leaflets. EDU did not contribute its nitrogen to leaf tissue as a fertiliser, as determined from lack of difference in foliar N between treatments. Both biochemical (increase in ascorbate-peroxidase and ascorbic acid, and decrease in apoplastic hydrogen peroxide) and biophysical (decrease in stomatal conductance) processes regulated EDU action. As total ascorbic acid increased only in the asymptomatic trees, its role in alleviating O3 effects on leaf growth and visible injury is controversial. - Both biochemical and biophysical processes may regulate EDU action

  4. PLASMA AND LUNG MACROPHAGE CAROTENOID RESPONSIVENESS TO SUPPLEMENTATION AND OZONE EXPOSURE IN HUMANS

    OBJECTIVE:: To examine the effect of ozone exposure and vegetable juice supplementation on plasma and lung macrophage concentrations of carotenoids. DESIGN:: A randomized trial. SETTING:: Subjects were exposed to ambient air prior to antioxidant supplementation and to ozone after...

  5. The effects of feed restriction and ambient temperature on growth and ascites mortality of broilers reared at high altitude.

    Ozkan, S; Takma, C; Yahav, S; Sögüt, B; Türkmut, L; Erturun, H; Cahaner, A

    2010-05-01

    The development of ascites was investigated in broilers at low versus high altitudes, cold versus normal ambient temperatures (AT), and 3 feeding regimens. One-day-old chicks obtained at sea level were reared at high altitude (highA; 1,720 m; n = 576) with 2 AT treatments, low AT from 3 wk onward at highA (highA/cold) and normal AT from 3 wk onward at highA (highA/norm), or at sea level (normal AT from 3 wk onward at low altitude, lowA/norm; n = 540). Under highA/cold, AT ranged between 16 to 17 degrees C in the fourth week, 17 to 19 degrees C in the fifth week, and 19 to 21 degrees C thereafter. Under highA/norm and lowA/norm, AT was 24 degrees C in the fourth week and ranged between 22 to 24 degrees C thereafter. Broilers in each condition were divided into 3 groups: feed restriction (FR) from 7 to 14 d, FR from 7 to 21 d, and ad libitum (AL). Ascites mortality and related parameters were recorded. Low mortality (0.4%) occurred under lowA/norm conditions. Under highA/norm, mortality was lower in females (8.6%) than in males (13.8%) and was not affected by the feeding regimen. The highA/cold treatment resulted in higher mortality but only in males; it was 44.2% among highA/cold AL-fed males and only about 26% under the FR regimens, suggesting that FR helped some males to better acclimatize to the highA/cold environment and avoid ascites. However, mortality was only 13.3% in AL-fed males at highA/norm and FR did not further reduce the incidence of ascites under these conditions. Thus, avoiding low AT in the poultry house by slight heating was more effective than FR in reducing ascites mortality at highA. Compared with FR from 7 to 14 d, FR from 7 to 21 d did not further reduce mortality and reduced growth. At 47 d, the majority of surviving broilers at highA had high levels of hematocrit and right ventricle:total ventricle weight ratio (>0.29), but they were healthy and reached approximately the same BW as their counterparts at low altitude. This finding may

  6. Ozone threat

    Ozone hole was first discovered in 1980. Thus 15 years even after the first warming, the world is no where near to the elimination of man made gases that threaten to destroy the ozone layer. Ozone depletion has become a matter of enormous threat which remains to be solved by the Scientists and intelligentia of the world. Ozone (O3) is a pungent poisonous gas. It forms a layer at a distance of about 15 miles above the earth's surface which helps shield living things from the sun shearing ultra violet light. If ozone is lost, more ultra violet light reaches the earth, which can lead to increasing rate of skin cancer, the death of micro organisms and the failure of crops and plants. It was in 1974 when it was discovered that Chlorofluorocarbons (CFCs) cold rise slowly to the upper atmosphere and destroy the earth's fragile ozone shield. Chlorofluorocarbons are commonly used as coolants (such as Freon) for home and automobile air conditioners and in the making of fast food containers. CFCs take about 100 years or more to reach he stratosphere to damage the ozone layers. In 1988, Scientists confirmed that upto 3% of the ozone layer over the more populated Northern Hemisphere has been destroyed. it is believed that for every 1% decrease in ozone, skin cancers are expected to rise 5 to 6 per cent due to the increase of ultraviolet light. Cases of cataracts and certain human immune system diseases are also expected to rise. (author)

  7. Einfluss von Ozon, CO2 und Trockenstress auf das Wachstum und die Pollenproduktion der Beifuß-Ambrosie (Ambrosia artemisiifolia)

    El Kelish, Amr; Winkler, J. Barbro; Lang, Hans; Holzinger, Andreas; Behrendt, Heidrun; Durner, Jörg; Kanter, Ulrike; Ernst, Dieter

    2014-01-01

    Climate change will affect the growth of plants and may also influence the production of pollen. The important factors influencing climate change are increased CO2 concentrations, drought and air pollution. Common ragweed pollen is known to be strongly allergenic, thereby affecting human health. In this study, common ragweed plants were grown over an entire vegetation period under conditions of twice the ambient level of CO2 (700 ppm) and ozone (80 ppm), respectively. Furthermore, the effect ...

  8. Ozone and cardiovascular injury

    Rainaldi Giuseppe

    2009-06-01

    and mortality 3. Most of the evidence comes from studies of ambient particles concentrations. However, in Europe and elsewhere, the air pollution profile has gradually changed toward a more pronounced photochemical component. Ozone is one of the most toxic components of the photochemical air pollution mixture. Indeed, the biological basis for these observations has not been elucidated. In the present review, the role of ozone as chemical molecule will be firstly considered. Secondly, pathogenetic mechanisms connecting the atmospheric ozone level and cardiovascular pathology will be examined. Thirdly, the literature relating hospitalization frequency, morbidity and mortality due to cardiovascular causes and ozone concentration will be studied. The correlation between ozone level and occurrence of acute myocardial infarction will be eventually discussed.

  9. Diferentes ambientes e Osmocote® na produção de mudas de tamarindeiro (Tamarindus indica Different ambient and Osmocote® for growth of tamarind (Tamarindus indica fruits seedlings

    Vander Mendonça

    2008-04-01

    Full Text Available Objetivou-se com este trabalho avaliar os efeitos de diferentes ambientes e doses de Osmocote® na produção de mudas de tamarindeiro (Tamarindus indica L. Um experimento foi instalado no Pomar da Universidade Federal de Lavras-MG, empregando-se delineamento experimental em blocos casualizados, em esquema fatorial 3 x 4, com quatro repetições e cinco plantas por parcela. Os tratamentos se constituíram dos diferentes ambientes de formação de mudas (casa de vegetação, telado e a céu aberto e de quatro doses de Osmocote®: 0; 3; 6 e 9 kg m-3 de substrato. Avaliaram-se a altura da muda (cm, comprimento da raiz (cm, número de folhas/planta, matéria seca da parte aérea (g, matéria seca da raiz (g e a matéria seca total (g. Os resultados demonstraram que o Osmocote® (15-10-10 pode ser recomendado para a formação de mudas de tamarindo, em doses de até 6,0 kg.m-3. O ambiente a céu aberto foi o que proporcionou melhor qualidade às mudas.This work aimed to evaluate the effect of ambient and Osmocote® (15-10-10 doses on the production of tamarind fruits seedlings. An experiment was carried out in a nursery at Universidade Federal de Lavras, Brazil, arranged in a randomized complete block outline and a 3x4 factorial scheme, with four replications and five plants per plot. The treatments were constituted by greenhouse, nursery and exposed sky, using different dosages of Osmocote® (15-10-10 were 0; 3; 6 e 9 kg m-3 of substrate. Seedling growth, height, number of leaves, aerial part, root and total dry matter were evaluated. The results showed that of Osmocote® (15-10-10 can be recommended for the formation of tamarind seedlings, at doses of until 6 kg m-3. Sky exposing was the one which provided better quality to the seedlings.

  10. Three days after a single exposure to ozone, the mechanism of airway hyperreactivity is dependent on substance P and nerve growth factor

    Verhein, Kirsten C.; Hazari, Mehdi S.; Moulton, Bart C; Jacoby, Isabella W.; Jacoby, David B.; Fryer, Allison D.

    2010-01-01

    Ozone causes persistent airway hyperreactivity in humans and animals. One day after ozone exposure, airway hyperreactivity is mediated by release of eosinophil major basic protein that inhibits neuronal M2 muscarinic receptors, resulting in increased acetylcholine release and increased smooth muscle contraction in guinea pigs. Three days after ozone, IL-1β, not eosinophils, mediates ozone-induced airway hyperreactivity, but the mechanism at this time point is largely unknown. IL-1β increases ...

  11. Ozone modeling

    Exhaust gases from power plants that burn fossil fuels contain concentrations of sulfur dioxide (SO2), nitric oxide (NO), particulate matter, hydrocarbon compounds and trace metals. Estimated emissions from the operation of a hypothetical 500 MW coal-fired power plant are given. Ozone is considered a secondary pollutant, since it is not emitted directly into the atmosphere but is formed from other air pollutants, specifically, nitrogen oxides (NO), and non-methane organic compounds (NMOQ) in the presence of sunlight. (NMOC are sometimes referred to as hydrocarbons, HC, or volatile organic compounds, VOC, and they may or may not include methane). Additionally, ozone formation Alternative is a function of the ratio of NMOC concentrations to NOx concentrations. A typical ozone isopleth is shown, generated with the Empirical Kinetic Modeling Approach (EKMA) option of the Environmental Protection Agency's (EPA) Ozone Isopleth Plotting Mechanism (OZIPM-4) model. Ozone isopleth diagrams, originally generated with smog chamber data, are more commonly generated with photochemical reaction mechanisms and tested against smog chamber data. The shape of the isopleth curves is a function of the region (i.e. background conditions) where ozone concentrations are simulated. The location of an ozone concentration on the isopleth diagram is defined by the ratio of NMOC and NOx coordinates of the point, known as the NMOC/NOx ratio. Results obtained by the described model are presented

  12. Ozone decomposition

    Batakliev, Todor; Georgiev, Vladimir; Anachkov, Metody; Rakovsky, Slavcho

    2014-01-01

    Catalytic ozone decomposition is of great significance because ozone is a toxic substance commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers). Considerable work has been done on ozone decomposition reported in the literature. This review provides a comprehensive summary of the literature, concentrating on analysis of the physico-chemical properties, synthesis and catalytic decomposition of ozone. This is supplemented by a review on kinetics and catalyst characterization which ties together the previously reported results. Noble metals and oxides of transition metals have been found to be the most active substances for ozone decomposition. The high price of precious metals stimulated the use of metal oxide catalysts and particularly the catalysts based on manganese oxide. It has been determined that the kinetics of ozone decomposition is of first order importance. A mechanism of the reaction of catalytic ozone decomposition is discussed, based on detailed spectroscopic investigations of the catalytic surface, showing the existence of peroxide and superoxide surface intermediates. PMID:26109880

  13. Initial field evaluation of the Harvard active ozone sampler for personal ozone monitoring.

    Geyh, A S; Roberts, P T; Lurmann, F W; Schoell, B M; Avol, E L

    1999-01-01

    Assessing personal exposure to ozone has only been feasible recently with the introduction of passive ozone samplers. These devices are easy to use, but changes in air velocity across their collection surfaces can affect performance. The Harvard active ozone sampler (AS) was developed in response to problems with the passive methods. This active sampler has been tested extensively as a microenvironmental sampler. To test for personal sampling, 40 children attending summer day-camp in Riverside, California wore the active ozone sampler for approximately 2.6 h on July 19 and 21, 1994, when ozone concentrations were about 100 ppb and 140 ppb, respectively. The children spent 94-100% of the sampling period outside, staying within a well-defined area while participating in normal camp activities. Ambient ozone concentrations across this area were monitored by two UV photometric ozone monitors. The active sampler was worn in a small backpack that was also equipped with a passive ozone sampler. Device precision, reported as the percent difference between duplicate pairs of samplers, was +/- 3.7% and +/- 4.2% for the active and passive samplers, respectively. The active sampler measured, on average, 94.5 +/- 8.2% of the ambient ozone while the passive samplers measured, on average, 124.5 +/- 18.8%. The samplers were worn successfully for the entire sampling period by all participating children. PMID:10321353

  14. Ambient Space and Ambient Sensation

    Schmidt, Ulrik

    The ambient is the aesthetic production of the sensation of being surrounded. As a concept, 'ambient' is mostly used in relation to the music genre 'ambient music' and Brian Eno's idea of environmental background music. However, the production of ambient sensations must be regarded as a central...... aspect of the aesthetization of modern culture in general, from architecture, transport and urbanized lifeforms to film, sound art, installation art and digital environments. This presentation will discuss the key aspects of ambient aesthetization, including issues such as objectlessness...

  15. Ozone as an ecotoxicological problem

    Mortensen, L. [National Environmental Research Inst., Dept. of Atmospheric Environment, Roskilde (Denmark)

    1996-11-01

    Ozone is quantitatively the dominating oxidant in photochemical air pollution. Other compounds like hydrogen peroxide, aldehydes, formate, peroxyacetyl nitrate (PAN) and nitrogen dioxide are present too, and several of these are known to be phytotoxic, but under Danish conditions the concentration of these gases are without significance for direct effects on vegetation. Therefore, it is the effects of ozone on plant growth that will be described below. (EG) 65 refs.

  16. Experimental studies on ozonation of ethylenethiourea

    Xinyu Dong; Junwang Meng; Bo Yang; Yang Zhang; Jie Gan; Xi Shu; Jinian Shu

    2011-01-01

    The experimental study on ozonation of ethylenethiourea (ETU) is conducted. The reaction of gas-phase ETU with 0.63 × l06 mol/L ozone is carried out in a 200-L reaction chamber. The secondary organic aerosol (SOA) resulted from the ozonation of gas-phase ETU is observed with a scanning mobility particle size (SMPS). The rapid exponential growth of SOA reveals that the atmospheric lifetime of ETU vapor towards ozone reaction is less than four days. The ozonation of dry ETU particles, ETU-contained water droplets and ETU aqueous solution is investigated with a vacuum ultraviolet photoionization aerosol time-of-flight mass spectrometer (VUVATOFMS). The formation of 2-imidazoline is observed in the ozonation of dry ETU particles and ETU-contained water droplets. The formation of 2-imidazoline and ethylenerea is observed in the ozonation of ETU aqueous solution.

  17. [Preliminary study on suitability of ozone sterilization in traditional Chinese medicine and its preparation].

    Hu, Yan-jun; Wang, Ya-qi; Wu, Zhen-feng; Lan, Ji-ping; Zhang, Li-guo; Yang, Ming

    2015-08-01

    Microbial contamination, growth and reproduction have a great influence on the quality of traditional Chinese medicine (TCM) and its preparation. TCM may be polluted by microbial in the production process due to ambient air, facilities and appliances and operating personnel, which affects the quality and efficacy of the final product. The GMP certification inspection standard of TCM manufacturing enterprises clearly established: "Sterilization methods of Chinese herbal medicine, intermediate products, finished products should follow the principle whether or not to change its quality", "TCM powder that used as medicine directly should follow the principle whether to do microbiological examinations". So it's particularly important for product quality, corporate energy consumption and its efficiency to choose the scientific and effective sterilization techniques and methods. Ozone is a kind of safe, environmentally friendly, efficient and no residue emerging sterilization technology. It has been widely applied in various fields of medical and health care and production and living. This paper mainly analyzed the ozone sterilization technology of TCM, aiming to explore the principle of ozone sterilization, the advantages, application status and existing problems and so on. The management regulations and implementation rules of ozone sterilization were summarized to make sterilization of Chinese medicine in the production, management, quality control and other aspects standardized, reasonable and scientific, and to provide the theoretical reference of the ozone sterilization technology for TCM and its preparation. PMID:26790281

  18. Ozone pollution and ozone biomonitoring in European cities Part II. Ozone-induced plant injury and its relationship with descriptors of ozone pollution

    Klumpp, A.; Ansel, W.; Klumpp, G.;

    2006-01-01

    Within the scope of a biomonitoring study conducted in twelve urban agglomerations in eight European countries, the ozone-sensitive bioindicator plant Nicotiana tabacum cv. Bel-W3 was employed in order to assess the occurrence of phytotoxic ozone effects at urban, suburban, rural and traffic......-exposed sites. The tobacco plants were exposed to ambient air for biweekly periods at up to 100 biomonitoring sites from 2000 to 2002. Special emphasis was placed upon methodological standardisation of plant cultivation, field exposure and injury assessment. Ozone-induced leaf injury showed a clearly increasing...... gradient from northern and northwestern Europe to central and southern European locations. The strongest ozone impact occurred at the exposure sites in Lyon and Barcelona, while in Edinburgh, Sheffield, Copenhagen and Düsseldorf only weak to moderate ozone effects were registered. Between-site differences...

  19. US EPA Region 9 1-Hour Ozone NAAQS Designations

    U.S. Environmental Protection Agency — Esri polygon shapefile of 1-hour ozone designated areas in US EPA Region 9. Nonattainment areas are geographic areas which have not met National Ambient Air Quality...

  20. US EPA Region 9 8-Hour Ozone Designated Areas

    U.S. Environmental Protection Agency — Polygon feature class of Nonattainment Areas for 2008 NAAQS 8 Hour Ozone. Nonattainment areas are geographic areas which have not met National Ambient Air Quality...

  1. Seasonal differences and within-canopy variations of antioxidants in mature spruce (Picea abies) trees under elevated ozone in a free-air exposure system

    Hofer, Nora; Alexou, Maria [Institute of Forest Botany and Tree Physiology, Chair of Tree Physiology, Albert-Ludwigs-University, Georges-Koehler-Allee 053/054, D-79110 Freiburg (Germany); Heerdt, Christian [Bioclimatology and Air Pollution Research, Department of Ecology, Technische Universitaet Muenchen, Life Science Center Weihenstephan, Am Hochanger 13, 85354 Freising (Germany); Loew, Markus [Ecophysiology of Plants, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Werner, Herbert [Bioclimatology and Air Pollution Research, Department of Ecology, Technische Universitaet Muenchen, Life Science Center Weihenstephan, Am Hochanger 13, 85354 Freising (Germany); Matyssek, Rainer [Ecophysiology of Plants, Technische Universitaet Muenchen, Am Hochanger 13, 85354 Freising (Germany); Rennenberg, Heinz [Institute of Forest Botany and Tree Physiology, Chair of Tree Physiology, Albert-Ludwigs-University, Georges-Koehler-Allee 053/054, D-79110 Freiburg (Germany); Haberer, Kristine [Institute of Forest Botany and Tree Physiology, Chair of Tree Physiology, Albert-Ludwigs-University, Georges-Koehler-Allee 053/054, D-79110 Freiburg (Germany)], E-mail: kristine.haberer@biologie.uni-freiburg.de

    2008-07-15

    The effect of free-air ozone fumigation and crown position on antioxidants were determined in old-growth spruce (Picea abies) trees in the seasonal course of two consecutive years (2003 and 2004). Levels of total ascorbate and its redox state in the apoplastic washing fluid (AWF) were increased under double ambient ozone concentrations (2 x O{sub 3}), whilst ascorbate concentrations in needle extracts were unchanged. Concentrations of apoplastic and symplastic ascorbate were significantly higher in 2003 compared to 2004 indicating a combined effect of the drought conditions in 2003 with enhanced ozone exposure. Elevated ozone had only weak effects on total glutathione levels in needle extracts, phloem exudates and xylem saps. Total and oxidised glutathione concentrations were higher in 2004 compared to 2003 and seemed to be more affected by enhanced ozone influx in the more humid year 2004 compared to the combined effect of elevated ozone and drought in 2003 as observed for ascorbate. - Antioxidant defence in sun and shade needles of Picea abies under free-air ozone fumigation in the seasonal course of two consecutive years.

  2. Depletion of stratospheric ozone over the Antarctic and Arctic: Responses of plants of polar terrestrial ecosystems to enhanced UV-B, an overview

    Rozema, Jelte [Department of Systems Ecology, Institute of Ecological Science, Climate Centre, Vrije Universiteit, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands)]. E-mail: jelte.rozema@ecology.falw.vu.nl; Boelen, Peter [Department of Systems Ecology, Institute of Ecological Science, Climate Centre, Vrije Universiteit, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands); Blokker, Peter [Department of Systems Ecology, Institute of Ecological Science, Climate Centre, Vrije Universiteit, De Boelelaan 1087, 1081 HV Amsterdam (Netherlands)

    2005-10-15

    Depletion of stratospheric ozone over the Antarctic has been re-occurring yearly since 1974, leading to enhanced UV-B radiation. Arctic ozone depletion has been observed since 1990. Ozone recovery has been predicted by 2050, but no signs of recovery occur. Here we review responses of polar plants to experimentally varied UV-B through supplementation or exclusion. In supplementation studies comparing ambient and above ambient UV-B, no effect on growth occurred. UV-B-induced DNA damage, as measured in polar bryophytes, is repaired overnight by photoreactivation. With UV exclusion, growth at near ambient may be less than at below ambient UV-B levels, which relates to the UV response curve of polar plants. UV-B screening foils also alter PAR, humidity, and temperature and interactions of UV with environmental factors may occur. Plant phenolics induced by solar UV-B, as in pollen, spores and lignin, may serve as a climate proxy for past UV. Since the Antarctic and Arctic terrestrial ecosystems differ essentially (e.g. higher species diversity and more trophic interactions in the Arctic), generalization of polar plant responses to UV-B needs caution. - Polar plant responses to UV-B may be different in the Arctic than Antarctic regions.

  3. Depletion of stratospheric ozone over the Antarctic and Arctic: Responses of plants of polar terrestrial ecosystems to enhanced UV-B, an overview

    Depletion of stratospheric ozone over the Antarctic has been re-occurring yearly since 1974, leading to enhanced UV-B radiation. Arctic ozone depletion has been observed since 1990. Ozone recovery has been predicted by 2050, but no signs of recovery occur. Here we review responses of polar plants to experimentally varied UV-B through supplementation or exclusion. In supplementation studies comparing ambient and above ambient UV-B, no effect on growth occurred. UV-B-induced DNA damage, as measured in polar bryophytes, is repaired overnight by photoreactivation. With UV exclusion, growth at near ambient may be less than at below ambient UV-B levels, which relates to the UV response curve of polar plants. UV-B screening foils also alter PAR, humidity, and temperature and interactions of UV with environmental factors may occur. Plant phenolics induced by solar UV-B, as in pollen, spores and lignin, may serve as a climate proxy for past UV. Since the Antarctic and Arctic terrestrial ecosystems differ essentially (e.g. higher species diversity and more trophic interactions in the Arctic), generalization of polar plant responses to UV-B needs caution. - Polar plant responses to UV-B may be different in the Arctic than Antarctic regions

  4. Ozone and Pulmonary Innate Immunity

    Hollingsworth, John W.; Kleeberger, Steven R.; Foster, W. Michael

    2007-01-01

    Ambient ozone (O3) is a commonly encountered environmental air pollutant with considerable impact on public health. Many other inhaled environmental toxicants can substantially affect pulmonary immune responses. Therefore, it is of considerable interest to better understand the complex interaction between environmental airway irritants and immunologically based human disease. The innate immune system represents the first line of defense against microbial pathogens. Intact innate immunity requ...

  5. Det ambiente

    Schmidt, Ulrik

    Om begrebet "det ambiente", der beskriver, hvad der sker, når vi fornemmer baggrundsmusikkens diskrete beats, betragter udsigten gennem panoramavinduet eller tager 3D-brillerne på og læner os tilbage i biografsædet. Bogen analyserer, hvorfan ambiente oplevelser skabes, og hvilke konsekvenser det...

  6. Ambient Sensors

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under the GNU LGPL licence version 3 or higher.

  7. Ambient Sensors

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under th

  8. Growth kinetics and long-term stability of CdS nanoparticles in aqueous solution under ambient conditions

    The ubiquity of naturally occurring nanoparticles in the aquatic environment is now widely accepted, but a better understanding of the conditions that promote their formation and persistence is needed. Using cadmium sulfide (CdS) as a model metal sulfide species, thiolate-capped CdS nanoparticles were prepared in the laboratory to evaluate how aquatic conditions influence metal sulfide nanoparticle growth and stability. This work examines CdS nanoparticle growth directly in aqueous solution at room temperature by utilizing the size-dependent spectroscopic properties of semiconductors detectable by UV/vis. CdS nanoparticle growth was governed by oriented attachment, a non-classical mechanism of crystallization in which small precursor nanoparticles coalesce to form larger nanoparticle products. Nanoparticle growth was slowed with increasing capping agent and decreasing ionic strength. In addition to examining the short-term (hours) growth of the nanoparticles, a long-term study was conducted in which cysteine-capped CdS nanoparticles were monitored over 3 weeks in solutions of various ionic strengths. The long-term study revealed an apparent shift from small nanoparticles to nanoparticles twice their original size, suggesting nanoparticle growth may continue through oriented attachment over longer time scales. High-ionic strength solutions resulted in salt-induced aggregation and eventual settling of nanoparticles within days, whereas low-ionic strength solutions were stable against settling over the course of the experiment. Sulfide recovery from cysteine-capped CdS nanoparticles as acid volatile sulfide was nearly quantitative after 2 weeks in fully oxygenated water, demonstrating significantly slowed oxidation of sulfide when complexed to Cd(II) within CdS nanoparticles. The nanoparticles were also shown to be resistant to oxidation by Fe(III) (hydr)oxide. This study illustrates that aggregation, rather than chemical oxidation, is likely more important to the

  9. Effects of ambient temperature and early open-field response on the behaviour, feed intake and growth of fast- and slow-growing broiler strains

    Nielsen, Birte Lindstrøm

    2012-01-01

    Increased activity improves broiler leg health, but also increases the heat production of the bird. This experiment investigated the effects of early open-field activity and ambient temperature on the growth and feed intake of two strains of broiler chickens. On the basis of the level of activity...... in an open-field test on day 3 after hatching, fast-growing Ross 208 and slow-growing i657 chickens were allocated on day 13 to one of the 48 groups. Each group included either six active or six passive birds from each strain and the groups were housed in floor-pens littered with wood chips and...... and weighing more, and with a less efficient feed conversion than HH chickens, with HC birds intermediate. A similar effect was found for Ross 208 only for feed intake from 27 to 41 days of age. Ross 208 chickens distributed themselves in the pen with a preference for cooler areas in the hottest...

  10. Effects of ozone on crops in north-west Pakistan

    Although ozone is well-documented to reduce crop yields in the densely populated Indo-Gangetic Plain, there is little knowledge of its effects in other parts of south Asia. We surveyed crops close to the city of Peshawar, in north-west Pakistan, for visible injury, linking this to passive measurements of ozone concentrations. Foliar injury was found on potato, onion and cotton when mean monthly ozone concentrations exceeded 45 ppb. The symptoms on onion were reproduced in ozone fumigation experiments, which also showed that daytime ozone concentrations of 60 ppb significantly reduce the growth of a major Pakistani onion variety. Aphid infestation on spinach was also reduced at these elevated ozone concentrations. The ozone concentrations measured in April–May in Peshawar, and used in the fumigation experiment, are comparable to those that have been modelled to occur over many parts of south Asia, where ozone may be a significant threat to sensitive crops. -- Highlights: ► Visible ozone injury to onion, cotton and potato was identified in north-west Pakistan. ► The symptoms on onion were reproduced by exposure to elevated ozone. ► Elevated ozone levels also significantly reduced onion growth. ► Levels of aphid infestation on spinach were lower under elevated ozone. ► These effects were observed at ozone levels that have been modelled to occur widely across south Asia. -- Ozone concentrations in NW Pakistan have adverse effects on sensitive crop species

  11. Multi-morphological growth of nano-structured In{sub 2}Se{sub 3} by ambient pressure triethylene glycol based solution syntheses

    Li, Tongfei; Wang, Jian; Lai, Junyun; Zheng, Xuerong; Liu, Weiyan; Ji, Junna [School of Materials Science and Engineering, Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education, Tianjin University, Tianjin 300072 (China); Liu, Hui [School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300401 (China); Jin, Zhengguo, E-mail: zhgjin@tju.edu.cn [School of Materials Science and Engineering, Key Laboratory for Advanced Ceramics and Machining Technology of Ministry of Education, Tianjin University, Tianjin 300072 (China)

    2015-10-15

    In{sub 2}Se{sub 3} nanoparticles, flower-like shaped and sheet-shaped nanocrystals were synthesized by a new, facile, ambient pressure triethylene glycol based solution chemical route using indium(III) chloride and selenium powder as precursors. The growing morphology, crystallization, chemical stoichiometry and light absorption property of the In{sub 2}Se{sub 3} products synthesized were characterized by TEM, HRTEM, FESEM, XRD, EDX and UV–vis–NIR measurements. Multi-morphological growth of the nano-structured In{sub 2}Se{sub 3} in triethylene glycol based solution syntheses with changed assisting agents and reaction styles was demonstrated. - Highlights: • Multimorphological growth of In{sub 2}Se{sub 3} was demonstrated based on solution chemistry. • A new, facile, low cost and fast air pressure TEG based solution process was used. • Nanoparticles, flower-like shaped and sheet-shaped nanocrystals were synthesized. • Morphology, crystallization, stoichiometry and light absorption was characterized. • Solution growth of β-In{sub 2}Se{sub 3} nanosheets was firstly reported by this submission.

  12. Det Ambiente

    Schmidt, Ulrik

    Det ambiente er iscenesættelsen af en karakteristisk sanseoplevelse, der er kendetegnet ved fornemmelsen af at være omgivet. I dag bliver begrebet om det ambiente mest anvendt i forbindelse med musikgenren ’ambient musik’. Det ambiente er dog ikke essentielt knyttet til det musikalske, men må...... forstås som et betydeligt bredere fænomen i den moderne æstetiske kultur, der spiller en væsentlig rolle i oplevelsen af moderne transportformer, arkitektur, film, lydkunst, installationskunst og digitale multimedieiscenesættelser. En forståelse af det ambiente er derfor centralt for forståelsen af en...... moderne æstetiseret oplevelseskultur i almindelighed. Da det ambiente ikke hidtil har været gjort til genstand for en mere indgående teoretisk behandling, er der dog stor usikkerhed omkring, hvad fænomenet overhovedet indebærer. Hovedformålet med Det ambiente – Sansning, medialisering, omgivelse er derfor...

  13. Influence of Feeding Enzymatically Hydrolyzed Yeast Cell Wall on Growth Performance and Digestive Function of Feedlot Cattle during Periods of Elevated Ambient Temperature

    Salinas-Chavira, J.; Arzola, C.; González-Vizcarra, V.; Manríquez-Núñez, O. M.; Montaño-Gómez, M. F.; Navarrete-Reyes, J. D.; Raymundo, C.; Zinn, R. A.

    2015-01-01

    In experiment 1, eighty crossbred steers (239±15 kg) were used in a 229-d experiment to evaluate the effects of increasing levels of enzymatically hydrolyzed yeast (EHY) cell wall in diets on growth performance feedlot cattle during periods of elevated ambient temperature. Treatments consisted of steam-flaked corn-based diets supplemented to provide 0, 1, 2, or 3 g EHY/hd/d. There were no effects on growth performance during the initial 139-d period. However, from d 139 to harvest, when 24-h temperature humidity index averaged 80, EHY increased dry matter intake (DMI) (linear effect, p0.10) on carcass characteristics. In experiment 2, four Holstein steers (292±5 kg) with cannulas in the rumen and proximal duodenum were used in a 4×4 Latin Square design experiment to evaluate treatments effects on characteristics of ruminal and total tract digestion in steers. There were no treatment effects (p>0.10) on ruminal pH, total volatile fatty acid, molar proportions of acetate, butyrate, or estimated methane production. Supplemental EHY decreased ruminal molar proportion of acetate (p = 0.08), increased molar proportion of propionate (p = 0.09), and decreased acetate:propionate molar ratio (p = 0.07) and estimated ruminal methane production (p = 0.09). It is concluded that supplemental EHY may enhance DMI and ADG of feedlot steers during periods of high ambient temperature. Supplemental EHY may also enhance ruminal fiber digestion and decrease ruminal acetate:propionate molar ratios in feedlot steers fed steam-flaked corn-based finishing diets. PMID:26194225

  14. Effect of different arbuscular mycorrhizal fungi on growth and physiology of maize at ambient and low temperature regimes

    Chen, Xiaoying; Song, Fengbin; Liu, Fulai;

    2014-01-01

    The effect of four different arbuscular mycorrhizal fungi (AMF) on the growth and lipid peroxidation, soluble sugar, proline contents, and antioxidant enzymes activities of Zea mays L. was studied in pot culture subjected to two temperature regimes. Maize plants were grown in pots filled with a...

  15. Ozonation of sediments from an urban lake: an exploratory investigation

    F. A Lage Filho

    2011-09-01

    Full Text Available An exploratory investigation was conducted on the effects of application of ozone on the removal of organic and inorganic contaminants and the reduction of settleable solids in urban lake sediments. Homogenized sediment samples were treated in a batch reactor with an external recirculation loop and ozone feed from a Venturi injector. The ozone generating system was fed with ambient air with small footprint and operational simplicity. Ozone mass application (g/h and contact time (min were varied over wide ranges during testing. The effects of the ozone mass applied per unit time and the contact time on contaminant removal efficiencies were analyzed and a trade - off between the costs of ozonation and of solids treatment and disposal was proposed. The minimum ozone mass application required for total contaminant removal apparently depended on the type of organic contaminant present. An apparent influence of inorganic contaminant speciation on the removal efficiency was found and discussed.

  16. Growth of ponderosa pine seedlings as affected by air pollution

    Momen, B.; Anderson, P. D.; Houpis, J. L. J.; Helms, J. A.

    The effect of air pollution on seedling survival and competitive ability is important to natural and artificial regeneration of forest trees. Although biochemical and physiological processes are sensitive indicators of pollution stress, the cumulative effects of air pollutants on seedling vigor and competitive ability may be assessed directly from whole-plant growth characteristics such as diameter, height, and photosynthetic area. A few studies that have examined intraspecific variation in seedling response to air pollution indicate that genotypic differences are important in assessing potential effects of air pollution on forest regeneration. Here, we studied the effects of acid rain (no-rain, pH 5.1 rain, pH 3.0 rain) and ozone (filtered, ambient, twice-ambient) in the field on height, diameter, volume, the height:diameter ratio, maximum needle length, and time to reach maximum needle length in seedlings of three families of ponderosa pine ( Pinus ponderosa Dougl. ex Laws). Seedling diameter, height, volume, and height:diameter ratio related significantly to their pre-treatment values. Twice-ambient ozone decreased seedling diameter compared with ozone-filtered air. A significant family-by-ozone interaction was detected for seedling height, as the height of only one of the three families was decreased by twice-ambient ozone compared with the ambient level. Seedling diameter was larger and the height:diameter ratio was smaller under pH 3.0 rain compared to either the no-rain or the pH 5.1-rain treatment. This suggests greater seedling vigor, perhaps due to a foliar fertilization effect of the pH 3.0 rain.

  17. Ozone depletion zone and ozone smog. Ozone chemistry fundamentals

    This book elucidates the fundamentals of the ozone theory. The knowledge verified through measurements is compiled, and the gaps in the knowledge of ozone are defined. While the knowledge of ozone appears to be well-established the gaps in the knowledge are responsible for uncertainties. Measurement methods for determination of the atmospheric concentration of ozone are described. Details are given about the basic processes of atmospheric ozone formation and ozone depletion and about the role of CFC. The factors which determine ozone concentrations in the southern hemisphere are described first because South Pole ozone formation processes, in spite of their complexity, are not as complex as North Pole ozone formation processes. The differences between these processes in the two polar regions are described. (orig.)

  18. Ambient Gestures

    Karam, Maria; Hare, Jonathon; Lewis, Paul; schraefel, m.c.

    2006-01-01

    We present Ambient Gestures, a novel gesture-based system designed to support ubiquitous ‘in the environment’ interactions with everyday computing technology. Hand gestures and audio feedback allow users to control computer applications without reliance on a graphical user interface, and without having to switch from the context of a non-computer task to the context of the computer. The Ambient Gestures system is composed of a vision recognition software application, a set of gestures to be p...

  19. Spring leaf flush in aspen (Populus tremuloides) clones is altered by long-term growth at elevated carbon dioxide and elevated ozone concentration

    McGrath, Justin M., E-mail: jmcgrath@illinois.ed [Department of Plant Biology, University of Illinois, Urbana-Champaign, 190 ERML, 1201 W. Gregory Drive, Urbana, IL 61801 (United States); Karnosky, David F., E-mail: karnosky@mtu.ed [School of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States); Ainsworth, Elizabeth A., E-mail: lisa.ainsworth@ars.usda.go [Department of Plant Biology, University of Illinois, Urbana-Champaign, 190 ERML, 1201 W. Gregory Drive, Urbana, IL 61801 (United States); USDA ARS Photosynthesis Research Unit, 147 ERML, 1201 W. Gregory Drive, Urbana, IL 61801 (United States)

    2010-04-15

    Early spring leaf out is important to the success of deciduous trees competing for light and space in dense forest plantation canopies. In this study, we investigated spring leaf flush and how long-term growth at elevated carbon dioxide concentration ([CO{sub 2}]) and elevated ozone concentration ([O{sub 3}]) altered leaf area index development in a closed Populus tremuloides (aspen) canopy. This work was done at the Aspen FACE experiment where aspen clones have been grown since 1997 in conditions simulating the [CO{sub 2}] and [O{sub 3}] predicted for approx2050. The responses of two clones were compared during the first month of spring leaf out when CO{sub 2} fumigation had begun, but O{sub 3} fumigation had not. Trees in elevated [CO{sub 2}] plots showed a stimulation of leaf area index (36%), while trees in elevated [O{sub 3}] plots had lower leaf area index (-20%). While individual leaf area was not significantly affected by elevated [CO{sub 2}], the photosynthetic operating efficiency of aspen leaves was significantly improved (51%). There were no significant differences in the way that the two aspen clones responded to elevated [CO{sub 2}]; however, the two clones responded differently to long-term growth at elevated [O{sub 3}]. The O{sub 3}-sensitive clone, 42E, had reduced individual leaf area when grown at elevated [O{sub 3}] (-32%), while the tolerant clone, 216, had larger mature leaf area at elevated [O{sub 3}] (46%). These results indicate a clear difference between the two clones in their long-term response to elevated [O{sub 3}], which could affect competition between the clones, and result in altered genotypic composition in future atmospheric conditions. - Spring leaf flush is stimulated by elevated [CO{sub 2}] and suppressed by elevated [O{sub 3}] in aspen (Populus tremuloides).

  20. Substrate Utilization by an Oxalate-Consuming Spirillum Species in Relation to Its Growth in Ozonated Water

    van der Kooij, D.; Hijnen, W. A. M.

    1984-01-01

    The nutritional versatility of a vibrio-shaped, oxalate-utilizing isolate, strain NOX, obtained from tap water supplied with low concentrations of formate, glyoxylate, and oxalate, was determined by growth experiments with low-molecular-weight carbon compounds at high (grams per liter) and very low (micrograms per liter) concentrations. The organism, which was identified as a Spirillum species, appeared to be specialized in the utilization of a number of carboxylic acids. Yields of 2.9 × 106 ...

  1. Stem juice production of the C4 sugarcane (Saccharum officinarum)is enhanced by growth at double-ambient CO2 and high temperature

    Four sugarcane cultivars were grown for three months in sunlit greenhouses under [CO2] of 360 (ambient) and 720(doubled) ppm and at temperatures (T) of 1.5 (near ambient) and 6.0C higher than outside ambient T. Leaf area, stem juice, plant biomass, leaf CO2 exchange rate (CER) and activities of PEP ...

  2. The Antarctic Ozone Hole

    Jones, Anna E.

    2008-01-01

    Since the mid 1970s, the ozone layer over Antarctica has experienced massive destruction during every spring. In this article, we will consider the atmosphere, and what ozone and the ozone layer actually are. We explore the chemistry responsible for the ozone destruction, and learn about why conditions favour ozone destruction over Antarctica. For…

  3. Deciduous shrubs for ozone bioindication: Hibiscus syriacus as an example

    Ozone-like visible injury was detected on Hibiscus syriacus plants used as ornamental hedges. Weekly spray of the antiozonant ethylenediurea (EDU, 300 ppm) confirmed that the injury was induced by ambient ozone. EDU induced a 75% reduction in visible injury. Injury was more severe on the western than on the eastern exposure of the hedge. This factor of variability should be considered in ozone biomonitoring programmes. Seeds were collected and seedlings were artificially exposed to ozone in filtered vs. not-filtered (+30 ppb) Open-Top Chambers. The level of exposure inducing visible injury in the OTC seedlings was lower than that in the ambient-grown hedge. The occurrence of visible injury in the OTC confirmed that the ozone sensitivity was heritable and suggested that symptomatic plants of this deciduous shrub population can be successfully used as ozone bioindicators. EDU is recommended as a simple tool for diagnosing ambient ozone visible injury on field vegetation. - An Italian population of the deciduous shrub Hibiscus syriacus, a common ornamental species in temperate zones, is recommended as ozone bioindicator

  4. Effects of ambient background gases on YBCO plume propagation under film growth conditions: Spectroscopic, ion probe, and fast photographic studies

    The formation, composition, and propagation of KrF laser-produced plasmas from Y1Ba2Cu3O7-x have been studied with emphasis on topics relevant to film growth by pulsed-laser deposition. Spatially and temporally resolved, high-resolution optical absorption and emission spectroscopy, fast ion probes, and fast photography [obtained with a gated, image-intensified CCD array detector (ICCD)] are employed to investigate both emitting and non-emitting species in the laser plume as well as the overall shape and propagation of the laser plasma in background gases of oxygen and xenon. Transient optical absorption spectroscopy is applied to study the composition of the plume of ejected material from the dense layer near the target surface to distances of several centimeters. Optical absorption persists long after the decay of plasma fluorescence, indicating a slower component to plume transport. The absorption of YO formed by YBCO ablation in vacuum and by-yttrium ablation in oxygen is presented. Fast electric ion probes are utilized to measure velocities and total collected charge of the positive ions in the expanding YBCO laser plasma from near-threshold, vacuum conditions into the high fluence, background gas conditions utilized for thin-film growth. The exponential attenuation of the positive ion flux transmitted through 50--300 mTorr background oxygen is measured and used to define an attenuation coefficient. The showing of the laser plasma and formation of shock structures due to gas collisions is studied by ion probe measurements and fast ICCD photography. A comparison between shock wave propagation and drag models is presented to describe the arrival time and shape of the ion probe current waveform with distance. 11 refs, 11 figs

  5. In situ laser ablation plasma diagnostics in the film growth regime-effects of ambient background gases

    This paper reports on the propagation of the laser-induced plasma formed by KrF irradiation of Y1Ba2Cu3O7 characterized in background pressures of oxygen and argon typically used for thin film growth. The ion current transmitted through the background gases was recorded along the normal to the irradiated pellet as a function of distance in order to measure the decreasing velocity and magnitude of the expanding plasma current due to collisional slowing and attenuation of the laser plume. The integrated ion charge delivered to a substrate at low pressures can be described by elastic scattering giving a general integral cross sections of σc [O2] = 3.2 x 10-16 cm2 and σc [Ar] = 2.7 x 10-16 cm2. At higher pressures, inelastic scattering leads to increased recombination and reactive conversion of ions indicated by increased fluorescence of all the species, which becomes dominated by fluorescence of YO and BaO. Spatially resolved fluorescence measurements indicate that the luminous boundary to the plasma follows a weak shock front which coincides with the ion flux propagation. The ion transmission is found to drop exponentially with distance and background pressure, in agreement with a simple scattering model which yields general scattering cross sections for ion-argon σi-Ar = 2.1 x 10-16 cm2 and ion-oxygen σi-O2 = 2.3 x 10-16 cm2 interactions in background pressures up to 300 mTorr. The general features of the plume deceleration are described in terms of a drag force model alloys

  6. Estimating the Influence of Oil and Gas Emissions on Urban Ozone and Associated Health Risks

    Capps, S.; Nsanzineza, R.; Turner, M. D.; Henze, D. K.; Zhao, S.; Russell, M. G.; Hakami, A.; Milford, J. B.

    2015-12-01

    Tropospheric ozone (O3) degrades air quality, impacting human health and public welfare. The National Ambient Air Quality Standard (NAAQS) is designed to limit these impacts, but certain areas in the continental U.S. exceed this standard. Mitigating O3 NAAQS exceedances by designing emissions controls can be complicated in urban areas because of the long-range transport of ozone and its gaseous precursors as well as the complex mix of local emissions sources. Recent growth of unconventional oil and gas development near urban areas in Colorado, Texas, and the northeastern corridor has exacerbated this problem. To estimate the contribution of emissions from oil and gas development to urban O3 issues, we apply the CMAQ adjoint, which efficiently elucidates the relative influence of emissions sources on select concentration-based metrics. Specifically, the adjoint is used to calculate the spatially-specific relative contributions of emissions of oxides of nitrogen (NOx) and volatile organic compounds (VOCs) throughout the continental U.S. to O3 NAAQS exceedances and to ozone-related health risks in select urban areas. By evaluating these influences for different urban areas, including one in California that has been managing air quality with adjacent oil and gas development for a longer period of time, we are able to compare and contrast the emissions control strategies that may be more effective in particular regions. Additionally, the resulting relationships between emissions and concentrations provide a way to project ozone impacts when measurements provide refined estimates of emissions from this sector.

  7. Ambient intelligence

    Sanders, David; Gegov, Alexander

    2006-01-01

    This paper considers some history and the state of the art of Ambient Intelligence and from that seeks to identify new topics and future work. Ubiquitous computing, communications, human-centric computer interaction, embedded systems, context awareness, adaptive systems and distributed device networks are considered.

  8. Ambient intelligence

    Weber, W; Aarts, E

    2005-01-01

    Addresses ambient intelligence used to support human contacts and accompany an individual''s path through the complicated modern world, from applications that are imminent, since they use essentially existing technologies, to ambitious ideas whose realization is still far away, due to major unsolved technical challenges.

  9. Contribution of some ozone depleting substances (ODS) and greenhouse gases (GHGs) on total column ozone growth at Srinagar (34°N, 74.8°E), India

    Jana, P. K.; Saha, D. K.; Sarkar, D.

    2013-02-01

    A critical analysis has been made on the contribution of CFC-11, CFC-12, CFC-113, CH3Cl, CH3Br, CCl4, CH3CCl3, HCFCs, halons, WMO (World Meteorological Organization) minor constituents, CH4, N2O and water vapour to the variation of total column ozone (TCO) concentration at the station in Srinagar (34°N, 74.8°E), India from 1992 to 2003. With the implementation of Montreal Protocol, though the concentrations of CFC-11, CFC-113, CH3Cl, CH3Br, CCl4 and CH3CCl3 had decreased, the concentrations of CFC-12, HCFCs, halons, WMO minor constituents, CH4, N2O and water vapour had increased, as a result of which TCO had risen from 1992 to 2003 at the above station. The nature of yearly variations of concentrations of the above ozone depleting substances and GHGs as well as ozone has been presented. Possible explanations for build-up of TCO have also been offered.

  10. Influence of ambient and enhanced ultraviolet-B radiation on the plant growth and physiological properties in two contrasting populations of Hippophae rhamnoides

    Two contrasting sea buckthorn (Hippophae rhamnoides L.) populations from low and high altitude regions were employed to investigate the effects of prevailing and enhanced ultraviolet-B (UV-B) radiation on plant growth and physiological properties under a UVB-enhanced/exclusion system. The experimental design included three UV-B regimes, including excluded (-UVB), near-ambient (NA) and enhanced UV-B (+UVB) radiation. Compared with the control (-UVB), NA caused the formation of smaller but thicker plant leaves in both sea buckthorn populations, paralleled with significant increments of carotenoids and UV-absorbing compounds as well as improved water economy. NA also induced more biomass partition from shoot to root, but CO2 assimilation rate (A), photosynthetic area and biomass accumulation were unaffected. The low-altitude population seemed sensitive to +uvB, as indicated by the decreases in total biomass, A and ascorbic acid content (Asa, an antioxidant) compared with NA. However, little +UVB effect occurred on the high-altitude population, and we suggest that the higher tolerance of this population could be associated with its specific morphological and physiological characteristics, such as small but thick leaves and high-level of Asa content, as well as its greater physiological modification in response to NA, e.g., increases in protective compounds (carotenoids and UV-absorbing compounds) and improvement in water economy, in comparison to the low-altitude population, which form an effective adaptation strategy to enhanced UV-B stress

  11. The Pal pathway required for ambient pH adaptation regulates growth, conidiation, and osmotolerance of Beauveria bassiana in a pH-dependent manner.

    Zhu, Jing; Ying, Sheng-Hua; Feng, Ming-Guang

    2016-05-01

    The Pal/Rim pathway essential for fungal adaptation to ambient pH has been unexplored in Beauveria bassiana, a classic fungal entomopathogen. Here, we show the characterized Pal pathway comprising transcription factor PacC and upstream six Pal partners (PalA/B/C/F/H/I) in B. bassiana. Their coding genes were all transcribed most abundantly in standard wild-type culture under the alkaline condition of pH 9. Deletion of pacC or each pal gene resulted in a significant delay of culture acidification in a minimal broth (initial pH = 7.3). This delay concurred with altered accumulation levels of intra/extracellular organic acids and drastically depressed expression of some enzyme genes required for the syntheses of oxalic and lactic acids. Our deletion mutants except ΔpalI showed growth defects and maximal sensitivity to NaCl, KCl, LiCl, or sorbitol at pH 9, an alkaline condition leading to fragmented vacuoles in their hyphal cells exposed to osmotic stress. In these mutants, conidiation was significantly facilitated at pH 3 more than at pH 7 but suppressed slightly at pH 9. Mild virulence defects also occurred in the absence of pacC or any pal gene. These changes were restored by targeted gene complementation. Taken together, PacC and Pal partners regulate the growth, conidiation, and osmotolerance of B. bassiana in a pH-dependent manner, highlighting their vitality for the fungal pH response. PMID:26754817

  12. Ozone reaction with interior building materials: Influence of diurnal ozone variation, temperature and humidity

    Rim, Donghyun; Gall, Elliott T.; Maddalena, Randy L.; Nazaroff, William W.

    2016-01-01

    Elevated tropospheric ozone concentrations are associated with increased morbidity and mortality. Indoor ozone chemistry affects human exposure to ozone and reaction products that also may adversely affect health and comfort. Reactive uptake of ozone has been characterized for many building materials; however, scant information is available on how diurnal variation of ambient ozone influences ozone reaction with indoor surfaces. The primary objective of this study is to investigate ozone-surface reactions in response to a diurnally varying ozone exposure for three common building materials: ceiling tile, painted drywall, and carpet tile. A secondary objective is to examine the effects of air temperature and humidity. A third goal is to explore how conditioning of materials in an occupied office building might influence subsequent ozone-surface reactions. Experiments were performed at bench-scale with inlet ozone concentrations varied to simulate daytime (ozone elevated) and nighttime (ozone-free in these experiments) periods. To simulate office conditions, experiments were conducted at two temperatures (22 °C and 28 °C) and three relative humidity values (25%, 50%, 75%). Effects of indoor surface exposures were examined by placing material samples in an occupied office and repeating bench-scale characterization after exposure periods of 1 and 2 months. Deposition velocities were observed to be highest during the initial hour of ozone exposure with slow decrease in the subsequent hours of simulated daytime conditions. Daily-average ozone reaction probabilities for fresh materials are in the respective ranges of (1.7-2.7) × 10-5, (2.8-4.7) × 10-5, and (3.0-4.5) × 10-5 for ceiling tile, painted drywall, and carpet tile. The reaction probability decreases by 7%-47% across the three test materials after two 8-h periods of ozone exposure. Measurements with the samples from an occupied office reveal that deposition velocity can decrease or increase with time

  13. Theoretical modelling of Staphylococcus aureus growth in a cooked meat product kept at ambient temperature using temperature profiles of selected Mexican cities Modelagem teórica de crescimento de Staphylococcus aureus em um produto à base de carne cozida deixada à temperatura ambiente, usando perfis de temperatura de cidades do México

    Rosa Baeza

    2009-03-01

    Full Text Available A theoretical model is used to predict the growth of Staphylococcus aureus in a pasteurized meat product kept at ambient temperatures for several hours. For this purpose, the temperature profiles of some cities of Mexico were combined with literature data on the kinetics of S. aureus growth. As shown by theoretical predictions, if the food is kept at ambient temperature, the average daily temperature may not give accurate predictions.Um modelo teórico é utilizado para prever o crescimento de Staphylococcus aureus em um produto à base de carne (pasteurizado deixado por várias horas à temperatura ambiente. Para isso, perfis de temperatura de algumas cidades do México foram combinados com resultados de literatura sobre a cinética de crescimento de S. aureus. Como demonstrado por previsões teóricas, se o alimento é deixado à temperatura ambiente, a utilização da média diária da temperatura pode não dar previsões exatas.

  14. Effects of dietary DL-2-hydroxy-4(methylthio)butanoic acid supplementation on growth performance, indices of ascites syndrome, and antioxidant capacity of broilers reared at low ambient temperature

    Yang, G. L.; Zhang, K. Y.; Ding, X. M.; Zheng, P.; Luo, Y. H.; Bai, S. P.; Wang, J. P.; Xuan, Y.; Su, Z. W.; Zeng, Q. F.

    2016-01-01

    This study examined the effects of dietary DL-2-hydroxy-4(methylthio)butanoic acid (DL-HMTBA) supplementation on growth performance, antioxidant capacity, and ascites syndrome (AS) in broilers reared at low ambient temperature (LAT) from 7 to 28 days of age. Eight hundred 7-day-old broilers were randomly assigned to two ambient temperatures (LAT and normal ambient temperature [NAT]), four supplemental DL-HMTBA levels (0.17, 0.34, 0.51, and 0.68 %) of the basal diet in a 2 × 4 factorial arrangement (ten replicate pens; ten birds/pen). LAT and NAT indicate temperatures of 12-14 and 24-26 °C in two chambers, respectively, and broilers were reared at these temperatures from 7 to 28 days of age. LAT significantly decreased body weight gain (P recommended supplemental of DL-HMTBA level was 0.46 %.

  15. Secondary maxima in ozone profiles

    R. Lemoine

    2004-01-01

    International audience Ozone profiles from balloon soundings as well as SAGE II ozone profiles were used to detect anomalous large ozone concentrations of ozone in the lower stratosphere. These secondary ozone maxima are found to be the result of differential advection of ozone-poor and ozone-rich air associated with Rossby wave breaking events. The frequency and intensity of secondary ozone maxima and their geographical distribution is presented. The occurrence and amplitude of ozone seco...

  16. Ozone Hole Over Antarctica

    2002-01-01

    These images from the Total Ozone Mapping Spectrometer (TOMS) show the progressive depletion of ozone over Antarctica from 1979 to 1999. This 'ozone hole' has extended to cover an area as large as 10.5 million square miles in September 1998. The previous record of 10.0 million square miles was set in 1996. The Antarctic ozone hole develops each year between late August and early October. Regions with higher levels of ozone are shown in red. NASA and NOAA instruments have been measuring Antarctic ozone levels since the early 1970s. Large regions of depleted ozone began to develop over Antarctica in the early 1980s. Ozone holes of substantial size and depth are likely to continue to form during the next few years, scientists hope to see a reduction in ozone loss as levels of ozone-destroying CFCs (chlorofluorocarbons) are gradually reduced. Credit: Images by Greg Shirah, NASA Goddard Space Flight Center Scientific Visualization Studio

  17. Ozone disintegration kinetics in the reactor for tyres decomposition

    The results of theoretical and experimental research of ozone disintegration kinetics in the chemical reactor which is developed for decomposition of tyres in the ozone-air environment are presented. Analytical expression for dependence of ozone concentration in the reactor from time and from parameters of the task, such as volume speed of ozone-air mixture feed on a reactor input, concentration of ozone on the input to the reactor, volume speed of output of the used mixture, reactor size, and square of its internal surface is obtained. It is shown that at the same speed of ozone-air mixture pro rolling through the reactor, with growth of ozone concentration on the input, value of stationary concentration in the reactor grows, remaining always less than concentration on the input. It is also shown that at the same ozone concentration on the input, with growth of speed of ozone-air mixture pro rolling through the reactor, value of stationary ozone concentration in the reactor also grows, remaining always less than ozone concentration on the input. The ozone disintegration kinetics in the reactor in a wide range of speed of ozone-air mixture pro rolling through the reactor (0.15, 0.30, 0.45, 0.60 m3/hour) and various ozone concentration on the input (5, 10, 15, 20 g/m3) is experimentally studied. It is shown that experimental results with good accuracy coincide with the theoretical. Direct experiment showed the essential influence of the internal surface of the reactor on the ozone disintegration kinetics.

  18. Ambient intelligence

    Basten, Twan; de Groot, Harmke

    2007-01-01

    ""This book is truly an eye-opener as it is the first book that relates the dream scenarios of Ambient Intelligence quantitatively to the technical challenges and requirements of the huge distributed and interoperable embedded systems needed to implement AmI systems in the real world. This book is strongly recommended to a wide spectrum of engineers interested to embark in this rapidly emerging and fascinating technology."" (From the foreword by Hugo De Man, Professor K.U. Leuven and Senior Research Fellow IMEC)

  19. Tropospheric Ozone and Photochemical Smog

    Sillman, S.

    2003-12-01

    global background ozone can make the effects of local pollution events everywhere more acute, and can also cause ecological damage in remote locations that are otherwise unaffected by urban pollution. Ozone at the global scale is also related to greenhouse warming.This chapter provides an overview of photochemical smog at the urban and regional scale, focused primarily on ozone and including a summary of information about particulates. It includes the following topics: dynamics and extent of pollution events; health and ecological impacts; relation between ozone and precursor emissions, including hydrocarbons and nitrogen oxides (NOx); sources, composition, and fundamental properties of particulates; chemistry of ozone and related species; methods of interpretation based on ambient measurements; and the connection between air pollution events and the chemistry of the global troposphere. Because there are many similarities between the photochemistry of ozone during pollution events and the chemistry of the troposphere in general, this chapter will include some information about global tropospheric chemistry and the links between urban-scale and global-scale events. Additional treatment of the global troposphere is found in Volume 4 of this work. The chemistry of ozone formation discussed here is also related to topics discussed in greater detail elsewhere in this volume (see Chapters 9.10 and 9.12) and in Volume 4.

  20. Air pollution by ozone across Europe during summer 2008. Overview of exceedances of EC ozone threshold values for April-September 2008

    2009-07-01

    This report provides an evaluation of ground-level ozone pollution in Europe for April-September 2008, based on information submitted to the European Commission under Directive 2002/3/EC on ozone in ambient air. Since Members States have not yet finally validated the submitted data, the conclusions drawn in this report should be considered as preliminary. (au)

  1. Air pollution by ozone across Europe during summer 2010. Overview of exceedances of EC ozone threshold values for April-September 2010

    2011-06-15

    This report provides an evaluation of ground-level ozone pollution in Europe for April-September 2010, based on information submitted to the European Commission under Directive 2002/3/EC on ozone in ambient air. Since Members States have not yet finally validated the submitted data, the conclusions drawn in this report should be considered as preliminary. (Author)

  2. Air pollution by ozone across Europe during summer 2009. Overview of exceedances of EC ozone threshold values for April-September 2009

    2010-03-15

    This report provides an evaluation of ground-level ozone pollution in Europe for April-September 2009, based on information submitted to the European Commission under Directive 2002/3/EC on ozone in ambient air. Since Members States have not yet finally validated the submitted data, the conclusions drawn in this report should be considered as preliminary. (Author)

  3. Crescimento e qualidade de mudas de pinhão-manso produzidas em ambiente protegido Growth and quality of physic nut seedlings produced in greenhouse

    Janaina Paulino

    2011-01-01

    Full Text Available Devido ao recente Programa de Produção de Biocombustíveis do Brasil, o interesse comercial tem crescido em relação à produção de pinhão-manso (Jatropha curcas L.. Informações sobre esta cultura ainda são escassas, o que remete a necessidade de mais pesquisas que possam estabelecer condições de adaptabilidade desta cultura em diferentes condições. Neste contexto, realizou-se um experimento para estudar o crescimento e a qualidade das mudas de pinhão-manso, produzidas em ambiente protegido; as mudas foram monitoradas até o momento de serem transplantadas para o campo. Foi analisada a influência dos tipos e volumes de recipientes, juntamente com diferentes substratos e formas de adubação; o consumo de água também foi analisado durante o experimento. De acordo com os resultados, as melhores taxas de crescimento e qualidade de mudas até a condição de transplantio, foram obtidas com a combinação do substrato comercial, maior tubete e adubo de liberação lenta.There has been an increasing interest in the commercial production of physic nut (Jatropha curcas L. due to the recent Brazilian Program of Biofuel Production. Information on this crop is still scarce and more research is necessary to set the grounds of crop adaptability in different local conditions. An experiment was set up on this issue under greenhouse environment. Growth and quality of physic nut seedlings was monitored up to transplanting time. The influence of types and volumes of seedling containers was analysed along with different substrates and fertilization strategies. The water use was also detailed in the trial. Results showed the best achievements of growth rate and seedling quality, at appropriate transplanting time, were reached from the combination of the commercial substrate, largest containers and fertilizers of slow nutrient liberation.

  4. Quantifying the impact of current and future tropospheric ozone on tree biomass, growth, physiology and biochemistry: A quantitative meta-analysis

    The northern hemisphere temperate and boreal forests currently provide an important carbon sink; however, current tropospheric ozone concentrations ([O3]) and [O3] projected for later this century are toxic to trees and have the potential to reduce the carbon sink strength of these forests. This met...

  5. Leaf injury characteristics of grassland species exposed to ozone in relation to soil moisture condition and vapour pressure deficit

    A range of plant species typical of semi-natural grasslands were tested for their sensitivity to short-term ozone injury under normal and reduced irrigation, and in relationship to air vapour pressure deficit. Potted specimens of 24 herbs, legumes and grasses were exposed during two seasons to four O3 treatments in open-top chambers. The ozone treatments were: (a) charcoal-filtered air; (b) charcoal-filtered air plus ozone to match ambient levels; (c) charcoal-filtered air plus O3 to ambient levels 1.5 and (d) charcoal-filtered air with ozone added to twice ambient levels during selected episodes of 7–13 d. During these ozone episodes, half of the plants in each ozone treatment received reduced irrigation (dry treatment) while the rest was kept under full irrigation (wet treatment). Type and date of first occurrence of leaf injury were noted during individual growth periods. Plants were harvested three times per year, and the percentage of injured leaves was recorded. Depending on species, injury symptoms were expressed as flecking (O3-specific injury), leaf yellowing or anthocyanin formation. Carum carvi and most species of the Fabaceae family (Onobrychis sativa, Trifolium repens, Trifolium pratense) were found to be most responsive to O3, injury occurring after only a few days of exposure in treatment (b). An episodic reduction in irrigation tended to reduce the expression of O3-specific symptoms, but only in species for which a reduction in soil moisture potential and an associated reduction in stomatal conductance during the dry episodes were observed. In other species, the protection from O3 injury seemed to be of little importance. Using artificial neural networks the injury response of nine species was analysed in relation to Species, stomatal conductance, ozone as AOT40 (accumulated exposure above a threshold of 0.04 ppm for periods with global radiation ≥ 50 W m−2 (Fuhrer et al., 1997)), mean relative growth rate, air vapour pressure deficit and

  6. Antarctic Ozone Hole, 2000

    2002-01-01

    Each spring the ozone layer over Antarctica nearly disappears, forming a 'hole' over the entire continent. The hole is created by the interaction of some man-made chemicals-freon, for example-with Antarctica's unique weather patterns and extremely cold temperatures. Ozone in the stratosphere absorbs ultraviolet radiation from the sun, thereby protecting living things. Since the ozone hole was discovered many of the chemicals that destroy ozone have been banned, but they will remain in the atmosphere for decades. In 2000, the ozone hole grew quicker than usual and exceptionally large. By the first week in September the hole was the largest ever-11.4 million square miles. The top image shows the average total column ozone values over Antarctica for September 2000. (Total column ozone is the amount of ozone from the ground to the top of the atmosphere. A relatively typical measurement of 300 Dobson Units is equivalent to a layer of ozone 0.12 inches thick on the Earth's surface. Levels below 220 Dobson Units are considered to be significant ozone depletion.) The record-breaking hole is likely the result of lower than average ozone levels during the Antarctic fall and winter, and exceptionally cold temperatures. In October, however (bottom image), the hole shrank dramatically, much more quickly than usual. By the end of October, the hole was only one-third of it's previous size. In a typical year, the ozone hole does not collapse until the end of November. NASA scientists were surprised by this early shrinking and speculate it is related to the region's weather. Global ozone levels are measured by the Total Ozone Mapping Spectrometer (TOMS). For more information about ozone, read the Earth Observatory's ozone fact sheet, view global ozone data and see these ozone images. Images by Greg Shirah, NASA GSFC Scientific Visualization Studio.

  7. Ozone mass transfer and kinetics experiments

    Bollyky, L.J.; Beary, M.M.

    1981-12-01

    Experiments were conducted at the Hanford Site to determine the most efficient pH and temperature levels for the destruction of complexants in Hanford high-level defense waste. These complexants enhance migration of radionuclides in the soil and inhibit the growth of crystals in the evaporator-crystallizer. Ozone mass transfer and kinetics tests have been outlined for the determination of critical mass transfer and kinetics parameters of the ozone-complexant reaction.

  8. Ozone mass transfer and kinetics experiments

    Experiments were conducted at the Hanford Site to determine the most efficient pH and temperature levels for the destruction of complexants in Hanford high-level defense waste. These complexants enhance migration of radionuclides in the soil and inhibit the growth of crystals in the evaporator-crystallizer. Ozone mass transfer and kinetics tests have been outlined for the determination of critical mass transfer and kinetics parameters of the ozone-complexant reaction

  9. Antarctic ozone depletion

    Antarctic ozone depletion is most severe during the southern hemisphere spring, when the local reduction in the column amount may be as much as 50 percent. The extent to which this ozone poor air contributes to the observed global ozone loss is a matter of debate, but there is some evidence that fragments of the 'ozone hole' can reach lower latitudes following its breakup in summer. Satellite data show the seasonal evolution of the ozone hole. A new dimension has been added to Antarctic ozone depletion with the advent of large volcanic eruptions such as that from Mount Pinatubo in 1991. (author). 5 refs., 1 fig

  10. Stratospheric ozone depletion

    The amount of stratospheric ozone and the reduction of the ozone layer vary according to seasons and latitudes. At present total and vertical ozone is monitored over all Austria. The mean monthly ozone levels between 1994 and 2000 are presented. Data on stratospheric ozone and UV-B radiation are published daily on the home page http: www.lebesministerium.at. The use of ozone depleting substances such as chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs) is provided. Besides, the national measures taken to reduce their use. Figs. 2, Tables 2. (nevyjel)

  11. The Antarctic ozone hole

    Since the mid 1970s, the ozone layer over Antarctica has experienced massive destruction during every spring. In this article, we will consider the atmosphere, and what ozone and the ozone layer actually are. We explore the chemistry responsible for the ozone destruction, and learn about why conditions favour ozone destruction over Antarctica. For the historical perspective, the events leading up to the discovery of the 'hole' are presented, as well as the response from the international community and the measures taken to protect the ozone layer now and into the future

  12. Tropospheric ozone and the environment II. Effects, modeling and control

    This was the sixth International Specialty Conference on ozone for the Air ampersand Waste Management Association since 1978 and the first to be held in the Southeast. Of the preceding five conferences, three were held in Houston, one in New England, and one in Los Angeles. The changing location continues to support the understanding that tropospheric ozone is a nationwide problem, requiring understanding and participation by representatives of all regions. Yet, questions such as the following continue to be raised over all aspects of the nation's efforts to control ozone. Are the existing primary and secondary National Ambient Air Quality Standards (NAAQS) for ozone the appropriate targets for the ozone control strategy, or should they be modified to more effectively accommodate new health or ecological effects information, or better fit statistical analyses of ozone modeling data? Are the modeling tools presently available adequate to predict ozone concentrations for future precursor emission trends? What ozones attainment strategy will be the best means of meeting the ozone standard? To best answer these and other questions there needs to be a continued sharing of information among researchers working on these and other questions. While answers to these questions will often be qualitative and location specific, they will help focus future research programs and assist in developing future regulatory strategies

  13. Contribution of some ozone depleting substances (ODS) and greenhouse gases (GHGs) on total column zone growth at Srinagar (34°N, 74.8°), India

    P K Jana; D K Saha; D Sarkar

    2013-02-01

    A critical analysis has been made on the contribution of CFC-11, CFC-12, CFC-113, CH2Cl, CH3Br, CCl4, CH3CCl3, HCFCs, halons, WMO (World Meteorological Organization) minor constituents, CH4, N2O and water vapour to the variation of total column ozone (TCO) concentration at the station in Srinagar (34°N, 74.8°E), India from 1992 to 2003. With the implementation of Montreal Protocol, though the concentrations of CFC-11, CFC-113, CH3Cl, CH3Br, CCl4 and CH3CCl3 had decreased, the concentrations of CFC-12, HCFCs, halons, WMO minor constituents, CH4, N2O and water vapour had increased, as a result of which TCO had risen from 1992 to 2003 at the above station. The nature of yearly variations of concentrations of the above ozone depleting substances and greenhouse gases as well as ozone has been presented. Possible explanations for build-up of TCO have also been offered.

  14. Effect of regular aerobic exercise with ozone exposure on peripheral leukocyte populations in Wistar male rats

    Afshar Jafari; Mohammad Ali Hosseinpour faizi; Fariba Askarian; Hassan Pourrazi

    2009-01-01

    • BACKGROUND: The immune system in endurance athletes may be at risk for deleterious effects of gasous pollutants such as ambient ozone. Therefore, this study was performed to assess the effect of regular aerobic exercise with ozone exposure on peripheral leukocytes populations in male Wistar rats.
    • METHODS: Twenty eight 8 weeks old rats were selected and randomly divided into four groups of ozone-u...

    • Rapid increases in tropospheric ozone production and export from China

      Verstraeten, Willem W.; Neu, Jessica L.; Williams, Jason E.; Bowman, Kevin W.; Worden, John R.; Boersma, K. Folkert

      2015-09-01

      Rapid population growth and industrialization have driven substantial increases in Asian ozone precursor emissions over the past decade, with highly uncertain impacts on regional and global tropospheric ozone levels. According to ozonesonde measurements, tropospheric ozone concentrations at two Asian sites have increased by 1 to 3% per year since 2000, an increase thought to contribute to positive trends in the ozone levels observed at North America’s West Coast. However, model estimates of the Asian contribution to North American ozone levels are not well-constrained by observations. Here we interpret Aura satellite measurements of tropospheric concentrations of ozone and its precursor NO2, along with its largest natural source, stratospheric ozone, using the TM5 global chemistry-transport model. We show that tropospheric ozone concentrations over China have increased by about 7% between 2005 and 2010 in response to two factors: a rise in Chinese emissions by about 21% and increased downward transport of stratospheric ozone. Furthermore, we find that transport from China of ozone and its precursors has offset about 43% of the 0.42 DU reduction in free-tropospheric ozone over the western United States that was expected between 2005 and 2010 as a result of emissions reductions associated with federal, state and local air quality policies. We conclude that global efforts may be required to address regional air quality and climate change.

    • OZONE UPTAKE OF DIFFERENT-SIZED BLACK CHERRY TREES IN HIGH- AND LOW-LIGHT ENVIRONMENTS

      Ozone uptake rates of different-sized black cherry trees located in both high and low light environments were calculated from measurements of ambient ozone concentration and stomatal conductance. he objective of the study was to determine how tree size and light conditions may di...

    • Ozone layer - climate change interactions. Influence on UV levels and UV related effects

      Kelfkens G; Bregman A; de Gruijl FR; van der Leun JC; Piquet A; van Oijen T; Gieskes WWC; van Loveren H; Velders GJM; Martens P; Slaper H; NOP; LPI; LLO

      2002-01-01

      Ozone in the atmosphere serves as a partially protective filter against the most harmful part of the solar UV-spectrum. Decreases in ozone lead to increases in ambient UV with a wide variety of adverse effects on human health, aquatic and terrestrial ecosystems and food chains. Human health effect

    • Prediction of lung function response for populations exposed to a wide range of ozone conditions

      Abstract Context: A human exposure-response (E-R) model that has previously been demonstrated to accurately predict population mean FEV1 response to ozone exposure has been proposed as the foundation for future risk assessments for ambient ozone. Objective: Fit the origi...

    • Ozone Trends Across the United States over a Period of Decreasing NOx and VOC Emissions

      In this work, we evaluate ambient ozone trends at urban, suburban, and rural monitoring sites across the United States over a period of decreasing NOx and VOC emissions (1998–2013). We find that decreasing ozone trends generally occur in the summer, in less urbanized areas,...

    • Ozone Layer Observations

      McPeters, Richard; Bhartia, P. K. (Technical Monitor)

      2002-01-01

      The US National Aeronautics and Space Administration (NASA) has been monitoring the ozone layer from space using optical remote sensing techniques since 1970. With concern over catalytic destruction of ozone (mid-1970s) and the development of the Antarctic ozone hole (mid-1980s), long term ozone monitoring has become the primary focus of NASA's series of ozone measuring instruments. A series of TOMS (Total Ozone Mapping Spectrometer) and SBUV (Solar Backscatter Ultraviolet) instruments has produced a nearly continuous record of global ozone from 1979 to the present. These instruments infer ozone by measuring sunlight backscattered from the atmosphere in the ultraviolet through differential absorption. These measurements have documented a 15 Dobson Unit drop in global average ozone since 1980, and the declines in ozone in the antarctic each October have been far more dramatic. Instruments that measure the ozone vertical distribution, the SBUV and SAGE (Stratospheric Aerosol and Gas Experiment) instruments for example, show that the largest changes are occurring in the lower stratosphere and upper troposphere. The goal of ozone measurement in the next decades will be to document the predicted recovery of the ozone layer as CFC (chlorofluorocarbon) levels decline. This will require a continuation of global measurements of total column ozone on a global basis, but using data from successor instruments to TOMS. Hyperspectral instruments capable of measuring in the UV will be needed for this purpose. Establishing the relative roles of chemistry and dynamics will require instruments to measure ozone in the troposphere and in the stratosphere with good vertical resolution. Instruments that can measure other chemicals important to ozone formation and destruction will also be needed.

  1. Ozone layer tragedy

    A brief introduction is given on how the ozone layer formed and about the factors depleted ozone layer such as chloro bromo compounds and so on; then, it follows the processes which destroy the troposphere. The damaging effect of ultraviolet radiation is described. Finally,the action taken to reduce the depletion of ozone layer is presented

  2. Ambient air pollution and the fetus

    Kadriye Yurdakök

    2013-01-01

    There is a growing evidence on the hazards of ambient air pollution on fetal development. Several review articles have been published on the adverse fetal outcomes including low birth weight, preterm birth, small-for-gestational age, and congenital anomalies. Recent studies have linked ambient air pollution to gestational hypertension, and preeclampsia which may be related to the detrimental effect of ambient air pollution on placental growth and function. Short-term and long-term exposure to...

  3. Earth's ozone layer

    The paper contain the actual results of investigations of the influence of the human activity on the Earth's ozone layer. History of the ozone measurements and of the changes in its concentrations within the last few years are given. The influence of the trace gases on both local and global ozone concentrations are discussed. The probable changes of the ozone concentrations are presented on the basis of the modelling investigations. The effect of a decrease in global ozone concentration on human health and on biosphere are also presented. (author). 33 refs, 36 figs, 5 tabs

  4. Impact of elevated CO2 and elevated O3 on Beta vulgaris L.: Pigments, metabolites, antioxidants, growth and yield

    The present study was conducted to assess morphological, biochemical and yield responses of palak (Beta vulgaris L. cv Allgreen) to ambient and elevated levels of CO2 and O3, alone and in combination. As compared to the plants grown in charcoal filtered air (ACO2), growth and yield of the plants increased under elevated CO2 (ECO2) and decreased under combination of ECO2 with elevated O3 (ECO2 + EO3), ambient O3 (ACO2 + AO3) and elevated O3 (EO3). Lipid peroxidation, ascorbic acid, catalase and glutathione reductase activities enhanced under all treatments and were highest in EO3. Foliar starch and organic carbon contents increased under ECO2 and ECO2 + EO3 and reduced under EO3 and ACO2 + AO3. Foliar N content declined in all treatments compared to ACO2 resulting in alteration of C/N ratio. This study concludes that ambient level of CO2 is not enough to counteract O3 impact, but elevated CO2 has potential to counteract the negative effects of future O3 level. -- Highlights: ► Elevated CO2 enhanced the growth and yield of palak. ► Ambient and elevated ozone reduced the growth and yield of the test plant. ► Elevated CO2 reduced negative effects of elevated O3 by reducing oxidative stress. ► Higher amelioration was recorded at elevated CO2 + O3 compared to ambient CO2 + O3. -- Predicted levels of CO2 have greater ameliorative potential against negative effects of elevated ozone compared to present day CO2 against ambient ozone

  5. Ozone pollution: rising concentrations despite French and EU efforts

    Ozone is the main indicator of photochemical pollution which is caused by a complex combination of primary pollutants formed by chemical reactions in the troposphere, in the presence of sunlight. These primary pollutants, otherwise known as precursors of ozone (nitrogen oxides, volatile organic compounds and carbon monoxide), are emitted both by natural sources and human activities. In urban areas, during the summer months, ozone is often the main cause of deterioration in air quality. Directive 2002/3/EC relating to ozone in ambient air entered into force on 9 September 2003, superseding the first ozone Directive (92/72/CE) of 21 September 1992. In the last 10 years, monitoring of ozone pollution has considerably progressed in France (the number of analysers has increased tenfold). Emissions of the ozone precursors fell significantly (-27%) between 1990 and 2000 in France as a result of combined efforts in all sectors of activity. However, between 1994 and 2002, ozone levels remained above the information threshold for the protection of human health and vegetation on average more than 100 days a year in rural areas and over 40 days a year in urban and peri-urban areas. Efforts undertaken both in France and other European countries aim to improve the situation and ensure compliance with the requirements of Directive 2002/3/EC. (author)

  6. Manifestation of solar activity processes in the Earth ozone layer

    Statistical analysis of total ozone and its vertical distribution was carried out on the base of data obtained by rocket soundings with the aim to reveal influence of solar activity. THe coherence between monthly mean total ozone data series for six latitudinal zones in the Northern Hemisphere and solar spots has weak but steady maxima for 9 and 13-15 years periods of oscillations. The value of coherence does not exceed 0.15 and growth to the higher latitudes. The analysis of ozone profiles for middle latitudes reveals the decrease in ozone concentration between 30-50 km for winter and increase for autumn. 20 refs.; 3 figs

  7. Ambient air pollution and low birthweight

    Pedersen, Marie; Giorgis-Allemand, Lise; Bernard, Claire;

    2013-01-01

    BACKGROUND: Ambient air pollution has been associated with restricted fetal growth, which is linked with adverse respiratory health in childhood. We assessed the effect of maternal exposure to low concentrations of ambient air pollution on birthweight. METHODS: We pooled data from 14 population...

  8. Measurement of Ground Level Ozone at Different Locations

    Yasmen A. Mustafa

    2012-01-01

    Full Text Available Problem statement: Ground level ozone is the most important index substance of photochemical smog. Photochemical smog is now observed in many urban and industrial centers around the world and it has become a common phenomenon in many large cities. Ozone is a most harmful pollutant for humans, in addition it plays an important role in damaging vegetation and materials. Therefore it becomes important to measure the ground level ozone at different locations especially in the center of cities. Approach: The ground level ozone concentration at different locations in Baghdad city was identified. Five different sites have been chosen to identify the ground level ozone concentration. Two sites were chosen as areas contained point source (power plant station in addition to high traffic load and the other three sites were chosen as areas containing heavy traffic only (line source. The measurement focuses on spring and fall because these periods display favorable meteorology to ozone formation. Results: During the research period the maximum values (peaks for ground level ozone concentration were observed in the fall: at Al-Za’afarania area 101ppb as an average, at Al-Dora 87 ppb as an average (which represent the point sources and at line source areas 48 ppb as an average. In spring, the peaks of ozone concentration observed to be at the same height, about 50 ppb for all sites. Conclusion: The results show that the effect of power plant stations in forming ozone is larger than traffic load. The comparison between the ground level ozone concentrations that measured during the research period in spring and fall and the Ambient Air Quality Standards (AAQS shows that: (1 No exceeded levels were observed in spring for all sites. (2 In the fall, the AAQS for ozone was exceeded in Al-Za’afarania area at 12: PM, 1: PM, 2: PM and 3: PM and in Al-Dora at 2: PM.

  9. In situ autumn ozone fumigation of mature Norway spruce - Effects on net photosynthesis

    Mikkelsen, Teis Nørgaard; Ro-Poulsen, H.

    2002-01-01

    Twelve cuvettes were installed on current year's twigs in the top of the canopy of a 35 years old Norway spruce stand in Denmark. From 10 to 16 hours, six of the cuvettes received 5-60 nl l(-1) ozone in addition to ambient air and six cuvettes received ambient air with a 40% reduced ozone...... was found that a mean increase in ozone concentration of 10 nl l(-1) reduced net photosynthesis with 7.4 %. This effect should be related to a pre-exposure during the season of AOT40 12.5 mul l(-1) h....

  10. Effect of ozone treatment on different cariogenic microorganisms in vitro.

    Fagrell, Tobias G; Dietz, Wolfram; Lingström, Peter; Steiniger, Frank; Norén, Jörgen G

    2008-01-01

    Ozone treatment has been presented and discussed in the literature, as one of the "new" ways to treat dental caries. The aim of this paper was to study the in vitro effect of ozone on some common oral microorganisms related to dental caries using scanning electron microscopy (SEM). The effect of ozone was tested on three different strains of mutans streptococci and one Lactobacillus strain. After exposure of bacteria to ozone treatment for 0 to 60 sec, cultivation on different chair side strips and agar plates took place. Preparation and performance of scanning electron analyses in a field emission scanning electron microscope at 10 kV was then carried out. It was found that gaseous ozone treatment for 20 seconds or more was effective to kill the different microorganisms in vitro. Treatment of 20, 40 and 60 seconds of ozone prevented the bacteria to grow on the different media. Treatment times shorter than 20 seconds resulted in varying results with a limited effect on bacterial growth for treatments of 5-10 sec, respectively. The difference between ozone-treated and untreated specimens was macroscopically readily discernable. None of the strains treated with ozone for 60 seconds showed any bacterial growth. Only samples with untreated bacteria could be found in the SEM analyses in form of large and high colonies. This study presents a clear result of the bactericide effect of ozon (in vitro) on four different strains of bacteria associated with dental caries. PMID:18973084

  11. Spontaneous Growth of ZnCO3 Nanowires on ZnO Nanostructures in Normal Ambient Environment: Unstable ZnO Nanostructures

    Pan, Z.; Tao, J.; Zhu, Y.; Huang, J.-F.; Paranthaman, M.P.

    2009-12-09

    ZnO nanowires, one of the most investigated nanostructures that promise numerous applications in nanophotonics, opto-electronics, and energy, are generally thought to be highly stable under ambient conditions because of their oxide nature. Here, we report that ZnO nanowires are actually extremely unstable even in normal ambient environment (70% RH, and {approx}350 ppm CO{sub 2}) because of atmospheric corrosion. When placed on an oxide substrate (e.g., glass slide) and exposed in air, ZnO nanowires tend to react with airborne moisture and CO{sub 2} to form amorphous ZnCO{sub 3} thin films and nanowires. The factors that specially affect the corrosion of ZnO nanowires in a laboratory environment include CO{sub 2}, humidity, and substrates. Our results suggest that a CO{sub 2}{sup -} and/or moisture-free environment are required in order for optimal applications of ZnO nanowires.

  12. Influenza virus infection, ozone exposure, and fibrogenesis.

    Jakab, G J; Bassett, D J

    1990-05-01

    Oxidant exposure following chemically induced lung injury exacerbates the tendency to develop pulmonary fibrosis. Influenza virus pneumonitis causes severe acute lung damage that, upon resolution, is followed by a persistent alveolitis and parenchymal changes characterized by patchy interstitial pneumonia and collagen deposition in the affected areas. To determine whether oxidant exposure exacerbates the virus-induced alveolitis and residual lung damage, mice were infected by aerosol inhalation with influenza A virus and continuously exposed to 0.5 ppm ozone or ambient air. Noninfected control mice were exposed to either ambient air or ozone. On various days during the first month after infection, groups of mice were sacrificed and their lungs assessed for acute injury (lung lavage albumin, total and differential cell counts, wet/dry ratios, and morphometry). At 30, 60, 90, and 120 days after infection, groups of mice were sacrificed for total and differential lavage cell counts, lung hydroxyproline content, and morphometric analysis. Ozone exposure did not alter the proliferation of virus in the lungs as quantitated by infectious virus titers of lung homogenates at 1, 4, 7, 10, and 15 days after virus infection but mitigated the virus-induced acute lung injury by approximately 50%. After Day 30 a shift in the character of the pulmonary lesions was observed in that continuous exposure to ozone potentiated the postinfluenzal alveolitis and structural changes in the lung parenchyma. Additional studies suggest that the mechanism for the enhanced postinfluenzal lung damage may be related to the oxidant impairing the repair process of the acute influenzal lung damage. These data demonstrate that ozone exposure mitigates acute virus-induced lung injury and potentiates residual lung damage. PMID:2339849

  13. Ozone and Water Stress: Effects on the Behaviour of Two White Clover Biotypes

    Massimo Fagnano

    Full Text Available ozone pollution, water stress, stomata conductance, ozone uptake, clover, OTC.Ozone is a strong oxidizing pollutant which derives by alteration of the photolytic NOx cycle and it accumulates in the troposphere spreading in rural areas and therefore determining injuries on natural vegetation and crops. Since its penetration occurs mainly through stomata, all factors which alter plant-atmosphere relations could be able to modify plant response to ozone. Interaction between ozone and water stress in Mediterranean environment was studied on ozone resistant and sensitive biotypes of white clover, which were grown in charcoal filtered and notfiltered Open Top Chambers in factorial combination with different levels of water supply. Measurements of biomass, leaf area and stomatal conductance were made during the growth period. Ozone injuries were estimated as not-filtered/filtered OTC yield ratio; the stomatal flux of ozone was estimated multiplying stomata conductance x diffusivity ratio between ozone and water vapour (0.613 x ozone hourly concentrations. The hourly values of ozone uptake were cumulated throughout the cropping periods of the two years. In the sensitive biotype, water stress reduced yield losses due to ozone from 38% to 22%, as well as yield losses due to water stress were reduced by the presence of ozone from 43% to 29%, while no interaction between ozone and water stress was observed in the resistant biotype. Biomass yield losses of the sensitive biotype were strictly correlated to cumulated ozone uptake (R2 = 0.99, while biomass yield losses of the resistant biotype were not affected by the ozone fluxes variations created by the treatments. Flux based models could better estimate yield losses due to ozone in Mediterranean environments in which other stresses could be contemporary present; therefore, the new European directives might replace the actual thresholds based

  14. The stratospheric ozone and the ozone layer

    An overview is presented of the principal characteristics of the stratospheric ozone in the Earth's atmosphere, with particular emphasis on the tropics and the ozone hole over the poles. Some effects produced in the atmosphere as a consequence of the different human activities will be described, and some data on stratospheric ozone will be shown. We point out the existence of a nucleus of least ozone in the tropics, stretching from South America to central Africa, with annual mean values less than 240 DU, a value lower than in the middle latitudes and close to the mean values at the South Pole. The existence of such a minimum is confirmed by mean values from measurements made on satellites or with earthbound instruments, for different sectors in Colombia, like Medellin, Bogota and Leticia

  15. Semiconductor Sensors Application for Definition of Factor of Ozone Heterogeneous Destruction on Teflon Surface

    Nataliya V. Finogenova

    2003-12-01

    Full Text Available In our paper we present the results of our research, which was carried out by means of semiconductor sensor techniques (SCS, which allowed evaluating heterogeneous death-rate of ozone (γ Teflon surface. When ozone concentration is near to Ambient Air Standard value, γ is assessed to be equal to 6,57*10-7. High technique response provide possibility to determine ozone contents in the air media and the percentage of ozone, decomposed on the communication surfaces and on the surfaces of installation in the low concentration range (1–100 ppb.

  16. Semiconductor Sensors Application for Definition of Factor of Ozone Heterogeneous Destruction on Teflon Surface

    Finogenova, Nataliya V.; Marina V. Strobkova; Avetisov, Alexander K.; Serge A. Kazakov; Fatima Kh. Chibirova; Ludmila A. Obvintseva

    2003-01-01

    In our paper we present the results of our research, which was carried out by means of semiconductor sensor techniques (SCS), which allowed evaluating heterogeneous death-rate of ozone (γ) Teflon surface. When ozone concentration is near to Ambient Air Standard value, γ is assessed to be equal to 6,57*10-7. High technique response provide possibility to determine ozone contents in the air media and the percentage of ozone, decomposed on the communication surfaces and on the surfaces of ...

  17. Ethylenediurea (EDU): A research tool for assessment and verification of the effects of ground level ozone on plants under natural conditions

    Ethylenediurea (EDU) has been widely used to prevent ozone (O3) injury and crop losses in crop plants and growth reductions in forest trees. Successful use requires establishing a dose/response curve for EDU and the proposed plant in the absence of O3 and in the presence of O3 before initiating multiple applications to prevent O3 injury. EDU can be used to verify foliar O3 symptoms in the field, and to screen plants for sensitivity to O3 under ambient conditions. Despite considerable research, the mode of action of EDU remains elusive. Additional research on the mode of action of EDU in suppressing O3 injury in plants may also be helpful in understanding the mode of action of O3 in causing injury in plants. - EDU is a verified and effective tool for the assessment of the effects of ozone on plants.

  18. Ozone chemistry in aqueous solution : ozone decomposition and stabilisation

    Eriksson, Margareta

    2005-01-01

    Ozone is used in many applications in the industry as an oxidising agent for example for bleaching and sterilisation. The decomposition of ozone in aqueous solutions is complex, and is affected by many properties such as, pH, temperature and substances present in the water. Additives can either accelerate the decomposition rate of ozone or have a stabilising effect of the ozone decay. By controlling the decomposition of ozone it is possible to increase the oxidative capacity of ozone. In this...

  19. Ozone and ozone injury on plants in and around Beijing, China

    Ozone (O3) levels were assessed for the first time with passive samplers at 10 sites in and around Beijing in summer 2012. Average O3 concentrations were higher at locations around Beijing than in the city center. Levels varied with site locations and ranged from 22.5 to 48.1 ppb and were highest at three locations. Hourly O3 concentrations exceeded 40 ppb for 128 h and 80 ppb for 17 h from 2 to 9 in August at one site, where it had a real-time O3 analyzer. Extensive foliar O3 injury was found on 19 species of native and cultivated trees, shrubs, and herbs at 6 of the 10 study sites and the other 2 sites without passive sampler. This is the first report of O3 foliar injury in and around Beijing. Our results warrant an extensive program of O3 monitoring and foliar O3 injury assessment in and around Beijing. - Highlights: • Plants have been threatened by high O3 concentration in and around Beijing, China. • 19 plant species are reported as obvious ambient O3 injury symptoms in Beijing. • The O3 injury symptoms occur more often where ambient O3 concentration is higher. • The results warrant more extensive and long-term study of ambient O3 in China. - First report of ozone incidence and ozone injury on plants in and around Beijing, China

  20. Stratosphere and ozone layer

    Human activities disturb natural balance of earth atmosphere, in short time in comparison with time of great climatic evolutions of the past. Rapid destruction of ozone layer, modifications of chemical balances in Arctic by similar processes to which observed in Antarctic, first experimental views of ozone decreasing in stratosphere and increasing in troposphere, are indications of human perturbation in ozone layer balance which protect us from solar radiation. 17 figs., 6 tabs., 27 refs

  1. Ozone flow visualization techniques

    Dickerson, R. R.; Stedman, D. H.

    1981-01-01

    Flow visualization techniques using ozone for tracing gas flows are proposed whereby ozone is detected through its strong absorption of ultraviolet light, which is easily made visible with fluorescent materials, or through its reaction with nitric oxide to form excited nitrogen dioxide, which in relaxing emits detectable light. It is shown that response speeds in the kHz range are possible with an ultraviolet detection system for initial ozone concentrations of about 1%.

  2. Effect of temperature coupling on ozone depletion prediction

    Chandra, S.; Butler, D. M.; Stolarski, R. S.

    1978-01-01

    The effects of chlorine perturbations on both the temperature and the ozone distribution in the stratosphere have been studied using a simplified radiative-photochemical model. The model solves the hydrostatic equation for total density in a self-consistent manner as the temperature is changed. Radiative coupling is found to have a significant effect on both the thermal structure and the ozone distribution, particularly in the 35-50-km region. By increasing the ClX mixing ratio by 5.0 ppbv, the temperature in this region is decreased by 5 to 10 K with a slight increase below 30 km. The local ozone depletion around 40 km due to added ClX is smaller compared with the estimate made by keeping the temperature fixed to the ambient condition. However, the integrated effect of radiative coupling is to increase the calculated column ozone depletion by 15% to 25% in this model.

  3. Ozone carcinogenesis in vitro and its co-carcinogenesis with radiation

    Ozone (O/sub 3/), a reactive species of oxygen, is an important natural constituent of the atmosphere. Background levels of ozone in the lower atmosphere may range up to 0.1 ppm and are modified by geographic elevation, solar radiation and climatic conditions. Since some ozone effects are radiomimetic, its actions may be enhanced in the presence of ionizing radiation from background and/or manmade sources. While stratospheric ozone spares the earth from excess solar ultraviolet (UV) radiation, high levels of ozone in the environment are toxic and present a health hazard to man. Excess environmental exposure to ozone can result from a variety of sources. Ozone is a key component in oxidant smog and in the vicinity of high electric voltage equipment when in operation. Ozone is widely used as a disinfectant for air and water, in bleaches, waxes, textiles, oils. and inorganic synthesis. Enhanced levels of ozone are found in planes flying at high altitudes. Because of the toxic nature of ozone and its potential hazard to man, its levels in the environment are subject to government regulation. The current standard is set at an hourly average of 235 μg/m/sup 3/ (0.12 ppm) not to be exceeded more than once per year. Urban areas with high levels of photochemical smog (e.g. Southern California) may experience high ambient ozone levels which can reach 0.5 ppm

  4. Ozone exposure of field-grown winter wheat affects soil mesofauna in the rhizosphere

    Schrader, Stefan, E-mail: stefan.schrader@vti.bund.d [Johann Heinrich von Thuenen-Institute (vTI), Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute of Biodiversity, Bundesallee 50, 38116 Braunschweig (Germany); Bender, Juergen; Weigel, Hans-Joachim [Johann Heinrich von Thuenen-Institute (vTI), Federal Research Institute for Rural Areas, Forestry and Fisheries, Institute of Biodiversity, Bundesallee 50, 38116 Braunschweig (Germany)

    2009-12-15

    A 2-year open-top chamber experiment with field-grown winter wheat (Triticum aestivum L. cv. Astron) was conducted to examine the effects of ozone on plant growth and selected groups of soil mesofauna in the rhizosphere. From May through June in each year, plants were exposed to two levels of O{sub 3}: non-filtered (NF) ambient air or NF+ 40 ppb O{sub 3} (NF+). During O{sub 3} exposure, soil sampling was performed at two dates according to different plant growth stages. O{sub 3} exposure reduced above- and below-ground plant biomass in the first year, but had little effect in the second year. The individual density of enchytraeids, collembolans and soil mites decreased significantly in the rhizosphere of plants exposed to NF+ in both years. Differences were highest around anthesis, i.e. when plants are physiologically most active. The results suggest that elevated O{sub 3} concentrations may influence the dynamic of decomposition processes and the turnover of nutrients. - Ozone reduced the individual densities of enchytraeids, collembolans and soil mites in the rhizosphere of winter wheat indirectly via the plant-soil-system.

  5. Ozone exposure of field-grown winter wheat affects soil mesofauna in the rhizosphere

    A 2-year open-top chamber experiment with field-grown winter wheat (Triticum aestivum L. cv. Astron) was conducted to examine the effects of ozone on plant growth and selected groups of soil mesofauna in the rhizosphere. From May through June in each year, plants were exposed to two levels of O3: non-filtered (NF) ambient air or NF+ 40 ppb O3 (NF+). During O3 exposure, soil sampling was performed at two dates according to different plant growth stages. O3 exposure reduced above- and below-ground plant biomass in the first year, but had little effect in the second year. The individual density of enchytraeids, collembolans and soil mites decreased significantly in the rhizosphere of plants exposed to NF+ in both years. Differences were highest around anthesis, i.e. when plants are physiologically most active. The results suggest that elevated O3 concentrations may influence the dynamic of decomposition processes and the turnover of nutrients. - Ozone reduced the individual densities of enchytraeids, collembolans and soil mites in the rhizosphere of winter wheat indirectly via the plant-soil-system.

  6. Effect of ambient-level gas-phase peroxides on foliar injury, growth, and net photosynthesis in Japanese radish (Raphanus sativus)

    Chen Xuan, E-mail: xuan66chen@yahoo.co.j [Chinese Research Academy of Environmental Science, No.8, Dayangfang, Anwai, Chaoyang District, Beijing 100012 (China); Aoki, Masatoshi [Faculty of Agriculture, Tokyo University of Agriculture and Technology, Saiwaicho 3-5-8, Fuchu-shi, Tokyo 183-8509 (Japan); Takami, Akinori [National Institute for Environmental Studies, Onogawa 16-2, Tsukuba-shi, Ibaraki 305-8506 (Japan); Chai Fahe [Chinese Research Academy of Environmental Science, No.8, Dayangfang, Anwai, Chaoyang District, Beijing 100012 (China); Hatakeyama, Shiro [Faculty of Agriculture, Tokyo University of Agriculture and Technology, Saiwaicho 3-5-8, Fuchu-shi, Tokyo 183-8509 (Japan)

    2010-05-15

    To investigate the effects of ambient-level gas-phase peroxides concurrent with O{sub 3} on foliar injury, photosynthesis, and biomass in herbaceous plants, we exposed Japanese radish (Raphanus sativus) to clean air, 50 ppb O{sub 3}, 100 ppb O{sub 3}, and 2-3 ppb peroxides + 50 ppb O{sub 3} in outdoor chambers. Compared with exposure to 100 ppb O{sub 3}, exposure to 2-3 ppb peroxides + 50 ppb O{sub 3} induced greater damage in foliar injury, net photosynthetic rates and biomass; the pattern of foliar injury and the cause of net photosynthetic rate reduction also differed from those occurring with O{sub 3} exposure alone. These results indicate for the first time that sub-ppb peroxides + 50 ppb O{sub 3} can cause more severe damage to plants than 100 ppb O{sub 3}, and that not only O{sub 3}, but also peroxides, could be contributing to the herbaceous plant damage and forest decline observed in Japan's air-polluted urban and remote mountains areas. - Ambient-level gas-phase peroxides coexisted with 50 ppb O{sub 3} may contribute to the herbaceous plants damage and forest decline observed in Japan.

  7. Effect of ambient-level gas-phase peroxides on foliar injury, growth, and net photosynthesis in Japanese radish (Raphanus sativus)

    To investigate the effects of ambient-level gas-phase peroxides concurrent with O3 on foliar injury, photosynthesis, and biomass in herbaceous plants, we exposed Japanese radish (Raphanus sativus) to clean air, 50 ppb O3, 100 ppb O3, and 2-3 ppb peroxides + 50 ppb O3 in outdoor chambers. Compared with exposure to 100 ppb O3, exposure to 2-3 ppb peroxides + 50 ppb O3 induced greater damage in foliar injury, net photosynthetic rates and biomass; the pattern of foliar injury and the cause of net photosynthetic rate reduction also differed from those occurring with O3 exposure alone. These results indicate for the first time that sub-ppb peroxides + 50 ppb O3 can cause more severe damage to plants than 100 ppb O3, and that not only O3, but also peroxides, could be contributing to the herbaceous plant damage and forest decline observed in Japan's air-polluted urban and remote mountains areas. - Ambient-level gas-phase peroxides coexisted with 50 ppb O3 may contribute to the herbaceous plants damage and forest decline observed in Japan.

  8. Exposure to ozone reduces influenza disease severity and alters distribution of influenza viral antigens in murine lungs.

    Wolcott, J A; Zee, Y. C.; Osebold, J W

    1982-01-01

    Exposure to ambient levels of ozone (0.5 ppm) was shown to alter the pathogenesis of respiratory infection after aerosol infection of mice with influenza A virus. A semiquantitative method for determination of the sites of virus replication by direct immunofluorescence indicated that exposure to ozone reduced the involvement of respiratory epithelium in the infectious process and resulted in a less widespread infection of the alveolar parenchyma. Furthermore, the ozone-mediated alteration in ...

  9. The effect of reciprocal treatments with ozone and ultraviolet-B radiations on photosynthesis and growth of perennial grass Elymus athericus

    Staaij, van de J.W.M.; Tonneijck, A.E.G.; Rozema, J.

    1997-01-01

    The impact on plant growth of the simultaneously changing factors of the global climate, rising tropospheric O3 concentrations and increasing UV-B radiation fluxes, has been tested in a combined glasshouse and growth chamber experiment. The saltmarsh grass species Elymus athericus was sequentially f

  10. 40 CFR Appendix D to Part 50 - Measurement Principle and Calibration Procedure for the Measurement of Ozone in the Atmosphere

    2010-07-01

    ... Procedure for the Measurement of Ozone in the Atmosphere D Appendix D to Part 50 Protection of Environment... Measurement of Ozone in the Atmosphere Measurement Principle 1. Ambient air and ethylene are delivered... atmospheres l = optical path length in cm In practice, a stable O3 generator is used to produce...

  11. 40 CFR 51.916 - What are the requirements for an Ozone Transport Region under the 8-hour NAAQS?

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false What are the requirements for an Ozone Transport Region under the 8-hour NAAQS? 51.916 Section 51.916 Protection of Environment ENVIRONMENTAL... IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air Quality Standard §...

  12. 40 CFR 51.914 - What new source review requirements apply for 8-hour ozone nonattainment areas?

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false What new source review requirements apply for 8-hour ozone nonattainment areas? 51.914 Section 51.914 Protection of Environment... OF IMPLEMENTATION PLANS Provisions for Implementation of 8-hour Ozone National Ambient Air...

  13. Effects of ambient and elevated CO2 on growth, chlorophyll fluorescence, photosynthetic pigments, antioxidants, and secondary metabolites of Catharanthus roseus (L.) G Don. grown under three different soil N levels.

    Singh, Aradhana; Agrawal, Madhoolika

    2015-03-01

    Catharanthus roseus L. plants were grown under ambient (375 ± 30 ppm) and elevated (560 ± 25 ppm) concentrations of atmospheric CO2 at different rates of N supply (without supplemental N, 0 kg N ha(-1); recommended N, 50 kg N ha(-1); and double recommended N, 100 kg N ha(-1)) in open top chambers under field condition. Elevated CO2 significantly increased photosynthetic pigments, photosynthetic efficiency, and organic carbon content in leaves at recommended (RN) and double recommended N (DRN), while significantly decreased total nitrogen content in without supplemental N (WSN). Activities of superoxide dismutase, catalase, and ascorbate peroxidase were declined, while glutathione reductase, peroxidase, and phenylalanine-ammonia lyase were stimulated under elevated CO2. However, the responses of the above enzymes were modified with different rates of N supply. Elevated CO2 significantly reduced superoxide production rate, hydrogen peroxide, and malondialdehyde contents in RN and DRN. Compared with ambient, total alkaloids content increased maximally at recommended level of N, while total phenolics in WSN under elevated CO2. Elevated CO2 stimulated growth of plants by increasing plant height and numbers of branches and leaves, and the magnitude of increment were maximum in DRN. The study suggests that elevated CO2 has positively affected plants by increasing growth and alkaloids production and reducing the level of oxidative stress. However, the positive effects of elevated CO2 were comparatively lesser in plants grown under limited N availability than in moderate and higher N availability. Furthermore, the excess N supply in DRN has stimulated the growth but not the alkaloids production under elevated CO2. PMID:25304238

  14. The pollution by ozone

    Air pollution by ozone is increasing in spite of several points to reduce it. If the process of ozone formation are complex, the sources of this pollution are well known: first, mobile sources with automobiles (49%), boats , trains and planes (13%), then are following paints and solvents(18%), thermal power plants(11%), and finally industry processing with 5%. (N.C.)

  15. Sensitivity analysis of ground level ozone in India using WRF-CMAQ models

    Sharma, Sumit; Chatani, Satoru; Mahtta, Richa; Goel, Anju; Kumar, Atul

    2016-04-01

    Ground level ozone is emerging as a pollutant of concern in India. Limited surface monitoring data reveals that ozone concentrations are well above the prescribed national standards. This study aims to simulate the regional and urban scale ozone concentrations in India using WRF-CMAQ models. Sector-specific emission inventories are prepared for the ozone precursor species at a finer resolution (36 × 36 km2) than used in previous studies. Meteorological fields developed using the WRF model are fed into the CMAQ model along with the precursor emissions to simulate ozone concentrations at a regional scale. The model is validated using observed ozone dataset. Sensitivity analysis is carried out to understand the effect of different precursor species and sources on prevailing ozone concentrations in India. The results show that NOx sensitive conditions prevail in India and control of NOx will result in more reduction in ozone than VOCs. However, further growth in the transport and power sector and decreasing VOC emissions from the residential sector may increase the sensitivity of VOCs towards ozone in the future. At the urban scale, presence of high NOx emissions form VOC limited conditions and reduction of NOx results in increase in ozone concentrations. However, this will help in improving regional scale ozone pollution in the downwind regions. A non-linear response has been observed while assessing the sectoral sensitivities of ozone formation. Transport sector is found to have the maximum potential for reducing ozone concentrations in India.

  16. Observing trends in total ozone and extreme ozone events

    Balcerak, Ernie

    2014-05-01

    The ozone layer in the stratosphere has been recovering since the 1989 Montreal Protocol reduced the use of ozone-destroying chlorofluorocarbons. Fitzka et al. observed trends in total ozone levels and the vertical distribution of ozone at Hoher Sonnblick, a mountain in Austria, from 1994 to 2011.

  17. Ozone-induced signaling in Arabidopsis thaliana

    Ahlfors, Reetta

    2008-01-01

    Tropospheric ozone (O3) is one of the most common air pollutants in industrialized countries, and an increasing problem in rapidly industrialising and developing countries in Asia, Africa and South America. Elevated concentrations of tropospheric O3 can lead to decrease in photosynthesis rate and therefore affect the normal metabolism, growth and seed production. Acute and high O3 episodes can lead to extensive damage leading to dead tissue in plants. Thus, O3 derived growth defects can lead ...

  18. Einfluss von Ozon, CO2 und Trockenstress auf das Wachstum und die Pollenproduktion der Beifuß-Ambrosie (Ambrosia artemisiifolia

    El Kelish, Amr

    2014-07-01

    Full Text Available Climate change will affect the growth of plants and may also influence the production of pollen. The important factors influencing climate change are increased CO2 concentrations, drought and air pollution. Common ragweed pollen is known to be strongly allergenic, thereby affecting human health. In this study, common ragweed plants were grown over an entire vegetation period under conditions of twice the ambient level of CO2 (700 ppm and ozone (80 ppm, respectively. Furthermore, the effect of soil drought combined with different CO2 levels was investigated. Scanning electron microscopy showed no change in surface morphology and size of CO2- and drought-treated pollen. Regarding morphological parameters, elevated CO2 resulted in an increased length of the stem and the main inflorescence and higher pollen yields, whereas drought reduced the stem and inflorescence lengths and resulted in a lower pollen yield, a result that was mitigated by elevated CO2. Twice the ambient level of ozone tends to result in a reduced pollen yield. However, this was not statistically significant. These findings support the idea that the conditions of climate change will influence the development of common ragweed pollen, thereby affecting public health.

  19. Ozone as an air pollutant

    Berg, Rolf W.

    1996-01-01

    A Danish new book on ozone as an air pollutant has been reviewed. The Book is "Ozon som luftforurening" by Jes Fenger, Published by "Danmarks Miljøundersøgelser, 1995.......A Danish new book on ozone as an air pollutant has been reviewed. The Book is "Ozon som luftforurening" by Jes Fenger, Published by "Danmarks Miljøundersøgelser, 1995....

  20. Thermo Scientific Ozone Analyzer Instrument Handbook

    Springston, S. R. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-03-01

    The primary measurement output from the Thermo Scientific Ozone Analyzer is the concentration of the analyte (O3) reported at 1-s resolution in units of ppbv in ambient air. Note that because of internal pneumatic switching limitations the instrument only makes an independent measurement every 4 seconds. Thus, the same concentration number is repeated roughly 4 times at the uniform, monotonic 1-s time base used in the AOS systems. Accompanying instrument outputs include sample temperatures, flows, chamber pressure, lamp intensities and a multiplicity of housekeeping information. There is also a field for operator comments made at any time while data is being collected.

  1. Aspects of UV-absorption spectroscopy on ozone in effluents of plasma jets operated in air

    Cold plasmas operating under atmospheric conditions have been in the focus of scientific attention not only due to their use in plasma medicine. Many of these plasma sources most notably produce ozone. This work presents a detailed ozone analysis on an atmospheric-pressure plasma jet operated in ambient air using ultraviolet (UV) absorption spectroscopy. A special focus is placed on the question whether other species are involved, or is the absorption signal due to ozone. For this, the wavelength dependence of the optical depth was measured and compared with the theoretical optical depth including the cross section of ozone. The results show that in the case of a MHz frequency driven atmospheric-pressure argon plasma jet the absorption signal in the UV range is solely due to ozone. Furthermore, this finding is verified by spectroscopic measurements in the IR spectral range. Additional space-resolved ozone density measurements are performed in the effluent of this jet with small oxygen admixtures by means of UV absorption spectroscopy. A funnel-shaped spatial ozone profile is found for all investigated oxygen admixtures. The highest ozone density develops on the effluent axis and in close vicinity to the jet nozzle. The maximal detected value is 1.5 × 1016 cm-3 for an oxygen admixture of 1%. In order to compare the results with non-space-resolved ozone detection methods the ozone net production rate is calculated.

  2. Cultivar specific plant-soil feedback overrules soil legacy effects of elevated ozone in a rice-wheat rotation system

    Li, Qi; Yang, Yue; Bao, Xuelian; Zhu, Jianguo; Liang, Wenju; Bezemer, T. Martijn

    2016-01-01

    Abstract Tropospheric ozone has been recognized as one of the most important air pollutants. Many studies have shown that elevated ozone negatively impacts yields of important crops such as wheat or rice, but how ozone influences soil ecosystems of these crops and plant growth in rotation systems is

  3. Ozone lidar monitoring

    An ozone lidar system was installed at the National Institute for Environmental Studies (36 deg. N, 140 deg. E) in March, 1988 and observation of ozone profiles commenced from August 1988. The lidar system consists of XeCl, XeF and KrF excimer lasers, 2 m and 56 cm telescope optics and data processing systems. Since the Ozone Lidar Monitoring Program of the Center for the Environmental Research started in October 1990, frequent measurements (more than 50 times per year) have been made. After checking the statistical and systematic errors, the ozone profiles were archived. Comparisons between the lidar data and SAGE II satellite data were done for mutual validation and gave good results. Seventy four vertical profiles of ozone archived for the period from August 1990 through December 1991 are presented in this report. The seasonal and altitudinal variations of stratospheric ozone distribution can be explained by generally understood transport and photochemical reaction processes. Longer term monitoring is required to detect trends in the vertical profile of ozone

  4. 75 FR 2938 - National Ambient Air Quality Standards for Ozone

    2010-01-19

    ... 1997 (62 FR 38856) by setting the primary standard at a level of 0.08 ppm, based on the annual fourth... the air quality criteria and standards for O 3 in September 2000 with a call for information (65 FR..., and form, respectively, of the primary O 3 standard (73 FR 16472- 16475). For these reasons,...

  5. Teale California Ambient Air Quality Standards for Ozone

    California Department of Resources — California Spatial Information System (CaSIL) is a project designed to improve access to geo-spatial and geo-spatial related data information throughout the state...

  6. Ambient salinity and osmoregulation, energy metabolism and growth in juvenile yellowtail kingfish (Seriola lalandi Valenciennes 1833) in a recirculating aquaculture system

    Blanco Garcia, A.; Partridge, G.; Flik, G.; Roques, J.A.C.; Abbink, W.

    2015-01-01

    The effects of salinity on plasma osmolality, branchial chloride cell density, feed consumption and conversion and growth performance of yellowtail kingfish (Seriola lalandi) were evaluated. Fish (11.6 ± 0.6 g) were kept for 29 days at 14, 18, 22, 26 (experimental) and 30 g L-1 (control) salinity in

  7. The effect of reciprocal treatments with ozone and ultraviolet-B radiation on photosynthesis and growth of perennial grass Elymus athericus

    The impact on plant growth of the simultaneously changing factors of the global climate, rising tropospheric O3 concentrations and increasing UV-B radiation fluxes, has been tested in a combined glasshouse and growth chamber experiment. The saltmarsh grass species Elymus athericus was sequentially fumigated for two weeks with O3 and for another two weeks irradiated with UV-B (vv). Exposure to elevated UV-B did not negatively affect photosynthesis or plant growth. Fumigation with O3 had a depressing effect on net photosynthesis, the number and biomass of flowers, the number of leaves and the number of shoots. O3-induced damage only was observed in plants which had been fumigated during the last two weeks of the experiment. Since interactive responses were not observed, results suggest different primary target sites for O3 and UV-B within the plant

  8. Stratospheric ozone depletion.

    Rowland, F Sherwood

    2006-05-29

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290-320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime-the 'Antarctic ozone hole'. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  9. DEVELOPMENTS IN OZONATION OF WATERS

    OĞUZ, Ensar; ÇELİK, Zeynep

    2001-01-01

    Ozone, has been used in both industrial and synthetic chemistry. From this point of view, ozone-organic chemistry related papaers have been published by many researcher. Forthermore; its role in air and water pollution problems is more important today. As a result of ozone researches, it is clear that ozone is to be the brightest expection for future in industrial, domestic, and driking water treatment. Ozone, a high grade oxidation matter, has been used for removing the pollutants and toxic ...

  10. Ozone - plant surface reactions an important ozone loss term?

    Hansel, Armin; Jud, Werner; Fischer, Lukas; Canaval, Eva; Wohlfahrt, Georg; Tissier, Alain

    2015-04-01

    Elevated tropospheric ozone concentrations are considered a toxic threat to plants responsible for global crop losses with associated economic costs of several billions dollar per year. Plant injuries have been related to the uptake of ozone through stomatal pores and oxidative effects damaging the internal leaf tissue. But a striking question remains: How much ozone enters the plant through open stomata and how much ozone is lost by chemical reactions at the plant surface? Until now surface losses are estimated from measured total ozone deposition fluxes and calculated stomatal conductance values. While stomatal conductance of CO2 and H2O is well understood and extensively used in describing plant atmosphere gas exchange, stomatal conductance of ozone is not well known. Here we use different Nicotiana tabacum varieties and find that surface reactions of ozone with diterpenoids synthesized by glandular trichomes reduce ozone flux through open stomata. Our measurements reveal that fast ozone loss at the plant surface is accompanied with prompt release of oxygenated volatile compounds. In the ozone fumigation experiments of different Nicotiana tabacum varieties the release of specific volatile oxy-VOCs allowed to identify the semi volatile precursor compounds at the plant surface. Ozone fumigation experiments with Norway spruce (Picea abies) and Scots Pine (Pinus sylvestris), two common species in the Northern Hemisphere, show also a significant ozone loss at the plant surface for Picea abies. Fluid dynamic calculations of ozone transport in the diffusive leaf boundary layer reveal a vertical but no horizontal ozone gradient thus reducing ozone fluxes through the pores in case of efficient ozone scavenging plant surfaces. We explain this efficient ozone protection mechanism by the porous surface architecture of plants in combination with unsaturated semi-volatile compounds deposited at the plant surface. These results show that unsaturated semi-volatile compounds at

  11. Psicologia do Ambiente

    Antunes, Dalila; Bernardo, Fátima; Palma-Oliveira, José-Manuel

    2011-01-01

    Na aplicação da Psicologia à área do AMBIENTE importa em primeiro lugar definir o que se entende, neste contexto, por ambiente. O conceito é entendido como toda a envolvente que rodeia o ser humano. Referimo-nos pois ao espaço físico e aos estímulos que nele existem (som, ar, paisagem…), dirigindo-se a Psicologia do Ambiente ao estudo e intervenção sobre a forma como o ambiente influencia o indivíduo ou grupos, e sobre o modo como o comportamento dos indivíduos e grupos influenciam o ambiente...

  12. Artificial ozone holes

    Dolya, S N

    2014-01-01

    This article considers an opportunity of disinfecting a part of the Earth surface, occupying a large area of ten thousand square kilometers. The sunlight will cause dissociation of molecular bromine into atoms; each bromine atom kills thirty thousand molecules of ozone. Each bromine plate has a mass of forty milligrams grams and destroys ozone in the area of hundred square meters. Thus, to form the ozone hole over the area of ten thousand square kilometers, it is required to have the total mass of bromine equal to the following four tons.

  13. Atmosphere and Ambient Space

    Schmidt, Ulrik

    Atmosphere and Ambient Space This paper explores the relation between atmosphere and ambient space. Atmosphere and ambient space share many salient properties. They are both ontologically indeterminate, constantly varying and formally diffuse and they are both experienced as a subtle, non......-signifying property of a given space. But from a certain point of view, the two concepts also designate quite dissimilar experiences of space. To be ’ambient’ means to surround. Accordingly, ambient space is that space, which surrounds something or somebody. (Gibson 1987: 65) Since space is essentially...... of a surrounding character, all space can thus be described as having a fundamentally ambient character. So what precisely is an ambient space, then? As I will argue in my presentation, ambient space is a sensory effect of spatiality when a space is experienced as being particularly surrounding: a ‘space effect...

  14. Effect of low-dose gaseous ozone on pathogenic bacteria

    Fontes Belchor

    2012-12-01

    Full Text Available Abstract Background Treatment of chronically infected wounds is a challenge, and bacterial environmental contamination is a growing issue in infection control. Ozone may have a role in these situations. The objective of this study was to determine whether a low dose of gaseous ozone/oxygen mixture eliminates pathogenic bacteria cultivated in Petri dishes. Methods A pilot study with 6 bacterial strains was made using different concentrations of ozone in an ozone-oxygen mixture to determine a minimally effective dose that completely eliminated bacterial growth. The small and apparently bactericidal gaseous dose of 20 μg/mL ozone/oxygen (1:99 mixture, applied for 5min under atmospheric pressure was selected. In the 2nd phase, eight bacterial strains with well characterized resistance patterns were evaluated in vitro using agar-blood in adapted Petri dishes (105 bacteria/dish. The cultures were divided into 3 groups: 1- ozone-oxygen gaseous mixture containing 20 μg of O3/mL for 5 min; 2- 100% oxygen for 5 min; 3- baseline: no gas was used. Results The selected ozone dose was applied to the following eight strains: Escherichia coli, oxacillin-resistant Staphylococcus aureus, oxacillin-susceptible Staphylococcus aureus, vancomycin-resistant Enterococcus faecalis, extended-spectrum beta-lactamase-producing Klebsiella pneumoniae, carbapenem-resistant Acinetobacter baumannii, Acinetobacter baumannii susceptible only to carbapenems, and Pseudomonas aeruginosa susceptible to imipenem and meropenem. All isolates were completely inhibited by the ozone-oxygen mixture while growth occurred in the other 2 groups. Conclusion A single topical application by nebulization of a low ozone dose completely inhibited the growth of all potentially pathogenic bacterial strains with known resistance to antimicrobial agents.

  15. Photochemical processes and ozone production in Finnish conditions

    Laurila, T.; Hakola, H. [Finnish Meteorological Inst., Helsinki (Finland). Air Quality Dept.

    1996-12-31

    Photochemical ozone production is observed in March-September. Highest ozone concentrations and production efficiencies are observed in spring in the northern parts and in summer in the southern parts of the country. VOC concentrations are relatively low compared to continental areas in general. During the growing season a substantial part of the total reactive mass of VOCs is of biogenic origin. Large forest areas absorb ozone substantially, decreasing the ambient ozone concentrations in central and northern parts of Finland where long-range transport of ozone is relatively important compared to local production. The aim of the work conducted at Finnish Meteorological Institute has been to characterise concentrations of photochemically active species in the boundary layer and their photochemical formation and deposition including the effects on vegetation. Also interactions between the boundary layer and free troposphere of ozone have been studied. In the future, fluxes of both biogenic species and air pollutants will be measured and the models will be further developed so that the photochemical and micrometeorological processes could be better understood

  16. Ozone: Concentration variabilities in a seasonally dry tropical climate

    This paper reports seasonal and diurnal variations in the ambient air concentrations of ozone in Varanasi city, India for the years 1989 and 1990. Different monitoring zones were established in the city on the basis of pollution sources, traffic densities, and structure of built-up areas. At most of the monitoring stations, two-hourly ozone concentrations frequently exceeded 60 μg m-3 during summer months. However, the zone dominated by residential colonies, offices, and cultivated land showed maximum O3 concentrations less than 60 μg m-3. Higher concentrations of ozone were mainly recorded in warmer months between 11 am to 4 pm. The highest concentration of 160 μg m-3 O3 was recorded in the month of April at Zone I which was mainly due to emissions from heavy-duty automobiles. Monthly average ozone concentrations were significantly correlated with temperature, relative humidity, wind speed, and atmospheric pressure. The frequency distribution of 2-h mean ozone concentrations was close to the logarithmic normal. Maximum 2-h mean O3 concentrations in some areas of Varanasi city were above the limit that has been shown to cause significant vegetation damage. The temporal variation in ozone concentrations was mainly due to the variations in meteorological conditions

  17. The Effect of Air Pollution on Ozone Layer Thickness in Troposphere over the State of Kuwait

    H. O. Al Jeran

    2009-01-01

    Full Text Available Troposphere ozone layer acts as a shield against all ultraviolet radiation approaching the planet Earth through absorption. It was noticed in mid 80s that ozone layer has thinned on the poles of the planet due to release of man-made substances commonly known as Ozone Depleting Substances, (ODS into its atmosphere. The consequences of this change are adverse as the harmful radiations reach to the surface of the earth, strongly influencing the crops yield and vegetation. These radiations are major cause of skin cancer that has long exposure to Ultra Violet (UV radiation. United States environmental protection agency and European community have imposed strict regulations to curb the emission of ODS and phase out schedules for the manufacture and use of ODS that was specified by Montreal protocol in 1987. Problem statement: This research deled with data analysis of ozone layer thickness obtained from Abu-Dhabi station and detailed measurement of air pollution levels in Kuwait. Approach: The ozone layer thickness in stratosphere had been correlated with the measured pollution levels in the State of Kuwait. The influence of import of ozone depletion substances for the last decade had been evaluated. Other factor that strongly affects the ozone layer thickness in stratosphere is local pollution levels of primary pollutants such as total hydrocarbon compounds and nitrogen oxides. Results: The dependency of ozone layer thickness on ambient pollutant levels presented in detail reflecting negative relation of both non-methane hydrocarbon and nitrogen oxide concentrations in ambient air. Conclusion: Ozone layer thickness in stratosphere had been measured for five years (1999-2004 reflecting minimum thickness in the month of December and maximum in the month of June. The ozone thickness related to the ground level concentration of non-methane hydrocarbon and can be used as an indicator of the health of ozone layer thickness in the stratosphere.

  18. Ozone health effects

    Ozone is a principal component of photochemical air pollution endogenous to numerous metropolitan areas. It is primarily formed by the oxidation of NOx in the presence of sunlight and reactive organic compounds. Ozone is a highly active oxidizing agent capable of causing injury to the lung. Lung injury may take the form of irritant effects on the respiratory tract that impair pulmonary function and result in subjective symptoms of respiratory discomfort. These symptoms include, but are not limited to, cough and shortness of breath, and they can limit exercise performance. The effects of ozone observed in humans have been primarily limited to alterations in respiratory function, and a range of respiratory physiological parameters have been measured as a function of ozone exposure in adults and children. These affects have been observed under widely varying (clinical experimental and environmental settings) conditions

  19. 2001 Ozone Design Value

    U.S. Environmental Protection Agency — Ozone is generated by a complex atmoshperic chemical process. Industrial and automobile pollutants in the form of oxides of nitrogen and hydrocarbons react in the...

  20. Revealing source signatures in ambient BTEX concentrations

    Management of ambient concentrations of Volatile Organic Compounds (VOCs) is essential for maintaining low ozone levels in urban areas where its formation is under a VOC-limited regime. The significant decrease in traffic-induced VOC emissions in many developed countries resulted in relatively comparable shares of traffic and non-traffic VOC emissions in urban airsheds. A key step for urban air quality management is allocating ambient VOC concentrations to their pertinent sources. This study presents an approach that can aid in identifying sources that contribute to observed BTEX concentrations in areas characterized by low BTEX concentrations, where traditional source apportionment techniques are not useful. Analysis of seasonal and diurnal variations of ambient BTEX concentrations from two monitoring stations located in distinct areas reveal the possibility to identify source categories. Specifically, the varying oxidation rates of airborne BTEX compounds are used to allocate contributions of traffic emissions and evaporative sources to observed BTEX concentrations. - BTEX sources are identified from temporal variations of ambient concentration

  1. Ozone Therapy in Dentistry

    Sudarshan, Ramachandran; Vijayabala, G. Sree

    2013-01-01

    With the advancements in the field of dentistry, new treatment protocols are budding day by day to combat human ailments in a much natural better and simpler way. One such advancement is the application of ozone in dentistry. Ozone is a natural element protects us from ultraviolet rays. It has several properties including analgesics, immunostimulant and antimicrobial properties. In Dentistry its uses are abundance from gingival diseases, infection control, temporomandibular disorders, radiati...

  2. Ozone therapy in periodontics

    Gupta, G; Mansi, B

    2012-01-01

    Gingival and Periodontal diseases represent a major concern both in dentistry and medicine. The majority of the contributing factors and causes in the etiology of these diseases are reduced or treated with ozone in all its application forms (gas, water, oil). The beneficial biological effects of ozone, its anti-microbial activity, oxidation of bio-molecules precursors and microbial toxins implicated in periodontal diseases and its healing and tissue regeneration properties, make the use of oz...

  3. Stratospheric ozone depletion

    Rowland, F. Sherwood

    2006-01-01

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the c...

  4. Experimental Study on Minimization of Sludge Production by Ozonation Process

    何圣兵; 薛罡; 王宝贞; 王琳

    2003-01-01

    Based on the hypothesis of reducing sludge production under cryptic growth conditions, ozone was used as cell lysis agent to treat excess sludge,and then the ozonated supernatant was returned to the aeration tank. The results show that COD and NH+4-N removal efficiencies in ozonation process were 87.96% and 84.42%, respectively. Meanwhile, a low excess sludge yield coefficient of 0. 113 ( g SS/g COD removed) was obtained. Compared with that of the control test, the process configuration decreased the excess sludge production by 51.3%.

  5. Ifluence of outer electrode material on ozone production in coaxial negative corona discharge fed by oxygen

    Orszagh, J.; Skalny, J. D.; Mason, N. J.

    2008-07-01

    The "electric odour", observed by Van Marum when oxygen was passing trough electric spark in 1785, has been later (1839), identified by Ch. F. Schonbeim as a new chemical compound named ozone (Stolarski 1999). Almost from those times ozone is widely used chemical compound. The effect of outer electrode material on the ozone production in negative corona discharge have been studied. Two electrodes with the same dimensions were used in the experiment. One was made of stainless steel other one of brass. First the outer electrode was mechanically cleaned to remove the layer of oxides. The reactor have been filled by pure oxygen and closed. Then the measurement (1 hour measurement of discharge current at the constant voltage and time dependence of ozone concentration in the reactor) was repeated 5 times without cleaning the surface to see the ageing effects. Especially the influence of electrode oxidation on ozone concentration was studied. The experiments have been carried out at atmospheric pressure and ambient temperature. The ozone concentration was measured by UV spectroscopy method directly in the discharge reactor. As one can expect the brass surface was oxidizing faster. After five measurements the electrode surface was covered by layer of greenish oxides. On the other hand the steel electrode surface had no visible oxides layer. The oxidation of the outer electrode had little systematic effect on the ozone concentration but in case of brass electrode the results were scattered in the range from 8000 ppm to 15000 ppm of ozone. It seems that the more oxides are created on the surface the less ozone is produced or the faster the ozone decomposition processes are (see Fig. 1). On the other hand in case of stainless steel electrode the ozone concentrations were comparable in all 5 measurements. Overall ozone concentration was higher in steel electrode. Figure 1: Time dependence of ozone concentration.

  6. Plant ozone injury symptoms

    Nouchi, I.; Odaira, T.; Sawada, T.; Oguchi, K.; Komeiji, T.

    1973-01-01

    A study of the phytotoxicity of ozone to plants was conducted in controlled-atmosphere greenhouses to determine if the symptoms of such exposure would be similar to symptoms exhibited by plants exposed to photochemical smog (which contains ozone) in the Tokyo area. Test plants used were herbaceous plants and woody plants, which were fumigated to 20 pphm ozone. Plants used as controls for the oxone exposure experiments were placed in a carbon filtered greenhouse. Herbaceous plants were generally sensitive to injury, especially Brassica rapa, Brassica pekinensis and others were extremely responsive species. In comparison with herbaceous plants, woody plants were rather resistant except for poplar. Depending on plant species and severity of injury, ozone-injury symptoms of herbaceous plants were bleaching, chlorosis, necrosis, and red-dish-brown flecks. Leaves of woody plants developed discrete, punctate spots, reddish-brown pigment on the upper surfaces and lastly defoliation. Ozone injury was typically confined to the upper leaf surfaces and notably greater mature leaves. Microscopic examination showed that pallisade cells were much more prone to ozone injury than other tissues.

  7. The ozone backlash

    While evidence for the role of chlorofluorocarbons in ozone depletion grows stronger, researchers have recently been subjected to vocal public criticism of their theories-and their motives. Their understanding of the mechanisms of ozone destruction-especially the annual ozone hole that appears in the Antarctic-has grown stronger, yet everywhere they go these days, they seem to be confronted by critics attacking their theories as baseless. For instance, Rush Limbaugh, the conservative political talk-show host and now-best-selling author of The Way Things Ought to Be, regularly insists that the theory of ozone depletion by CFCs is a hoax: bladerdash and poppycock. Zoologist Dixy Lee Ray, former governor of the state of Washington and former head of the Atomic Energy Commission, makes the same argument in her book, Trashing the Planet. The Wall Street Journal and National Review have run commentaries by S. Fred Singer, a former chief scientists for the Department of Transportation, purporting to shoot holes in the theory of ozone depletion. Even the June issue of Omni, a magazine with a circulation of more than 1 million that publishes a mixture of science and science fiction, printed a feature article claiming to expose ozone research as a politically motivated scam

  8. Ozone depletion calculations

    Models of stratospheric chemistry have been primarily directed toward an understanding of the behavior of stratospheric ozone. Initially this interest reflected the diagnostic role of ozone in the understanding of atmospheric transport processes. More recently, interest in stratospheric ozone has arisen from concern that human activities might affect the amount of stratospheric ozone, thereby affecting the ultraviolet radiation reaching the earth's surface and perhaps also affecting the climate with various potentially severe consequences for human welfare. This concern has inspired a substantial effort to develop both diagnostic and prognostic models of stratospheric ozone. During the past decade, several chemical agents have been determined to have potentially significant impacts on stratospheric ozone if they are released to the atmosphere in large quantities. These include oxides of nitrogen, oxides of hydrogen, chlorofluorocarbons, bromine compounds, fluorine compounds and carbon dioxide. In order to assess the potential impact of the perturbations caused by these chemicals, mathematical models have been developed to handle the complex coupling between chemical, radiative, and dynamical processes. Basic concepts in stratospheric modeling are reviewed

  9. Temporal Variations in Concentrations of Ozone, Nitrogen Dioxide, and Carbon Monoxide at Osijek, Croatia

    Elvira Kovač-Andrić; Tatjana Radanović; Iva Topalović; Berislav Marković; Nikola Sakač

    2013-01-01

    The purpose of this study was to investigate the ozone, carbon monoxide, and nitrogen dioxide variations and their correlation with meteorological parameters in Osijek (Eastern Croatia) during the summer seasons of 2002, 2007, and 2012. The measured data are discussed in relation to the EU guidelines (Directive 2002/3/EC, Directive 2008/50/EC). In order to characterize ambient air with respect to ozone photochemical pollution we calculated three photochemical pollution indicators. These indic...

  10. Continuous laser irradiation under ambient conditions: A simple way for the space-selective growth of gold nanoparticles inside a silica monolith

    Highlights: → Visible continuous laser direct-write gold nanoparticles inside a silica monolith. → The presence of the additive (Na2CO3) is not necessary to the growth of gold nanoparticles. → A simple heat treatment leads to precipitation of gold nanoparticles inside the silica matrices with, or without, the additive. → The local precipitation of gold nanoparticles by continuous photo-irradiation occurs following a photo-thermal activated mechanism. -- Abstract: Thanks to the potential and various applications of metal-dielectric nanocomposites, their syntheses constitute an interesting subject in material research. In this work, we demonstrate the achievement of gold nanocrystals growth through a visible and continuous laser irradiation. The in situ and direct space-selective generation of metallic nanoparticles is localized under the surface within transparent silica monoliths. For that purpose, the porous silica monoliths are prepared using a sol-gel route and post-doped with gold precursors before the irradiation. The presence of Au nanoparticles inside the irradiated areas was evidenced using absorption spectroscopy, X-ray diffraction analysis and transmission electron microscopy. The comparison between the results obtained after a laser irradiation and by a simple heat-treatment reveals that the local precipitation of gold nanoparticles by continuous photo-irradiation occurs following a photo-thermal activated mechanism.

  11. Chloroplastic and stomatal aspects of ozone-induced reduction of net photosynthesis in plants

    Torsethaugen, Gro

    1998-09-01

    The present thesis relates to ozone-induced reduction of photosynthesis in plants. As a photochemical oxidant O{sub 3} is formed by the interaction of hydrocarbons, nitrogen oxides and oxygen in sunlight. Ozone (O{sub 3}) is the most phytotoxic of all the air pollutants and is known to reduce plant growth and net photosynthesis, cause stomatal closure, induce visible injury, accelerate senescence and induce or inhibit transcription of a variety of genes with a corresponding increase/decrease in protein products. The underlying cellular mechanisms for many of these changes are unknown. Following fields are investigated: Ozone-induced reduction of net photosynthesis; ozone and the photosynthetic apparatus in the chloroplasts; ozone and stomata; ozone effects on plant membranes; protection against ozone injury in plants. 249 refs., 22 figs., 4 tabs.

  12. Ozone: The secret greenhouse gas

    The atmospheric ozone not only protects against harmful ultraviolet radiation; it also contributes to the greenhouse effect. Ozone is one of the jokers to make it difficult to calculate the climatic effect of anthropogenic emissions. The greenhouse effect and the ozone layer should not be confused. The greenhouse effect creates problems when it becomes enhanced, so that the earth becomes warmer. The problem with the ozone layer, on the contrary, is that it becomes thinner and so more of the harmful ultraviolet radiation gets through to the earth. However, ozone is also a greenhouse gas and so the greenhouse effect and the ozone layer are connected

  13. Effects of dietary DL-2-hydroxy-4(methylthio)butanoic acid supplementation on growth performance, indices of ascites syndrome, and antioxidant capacity of broilers reared at low ambient temperature

    Yang, G. L.; Zhang, K. Y.; Ding, X. M.; Zheng, P.; Luo, Y. H.; Bai, S. P.; Wang, J. P.; Xuan, Y.; Su, Z. W.; Zeng, Q. F.

    2016-08-01

    This study examined the effects of dietary DL-2-hydroxy-4(methylthio)butanoic acid (DL-HMTBA) supplementation on growth performance, antioxidant capacity, and ascites syndrome (AS) in broilers reared at low ambient temperature (LAT) from 7 to 28 days of age. Eight hundred 7-day-old broilers were randomly assigned to two ambient temperatures (LAT and normal ambient temperature [NAT]), four supplemental DL-HMTBA levels (0.17, 0.34, 0.51, and 0.68 %) of the basal diet in a 2 × 4 factorial arrangement (ten replicate pens; ten birds/pen). LAT and NAT indicate temperatures of 12-14 and 24-26 °C in two chambers, respectively, and broilers were reared at these temperatures from 7 to 28 days of age. LAT significantly decreased body weight gain ( P AOC) at 21 days ( P = 0.001, 0.015) and 28 days ( P = 0.017, 0.010) and increased feed conversion ratio (FCR) ( P < 0.001), serum malondialdehyde (day 21, P = 0.000) and protein carbonyl Level (day 14, P = 0.003; day 21, P = 0.035). As for incidence of AS, there were significant effects of LAT on red blood cell (RBC) count ( P < 0.05), hematocrit (HCT) ( P < 0.05), and the right to total ventricular weight ratio (RV/TV) at 21 days ( P = 0.012) and 28 days ( P = 0.046). Supplementation of DL-HMTBA markedly decreased RV/TV at day 28 ( P = 0.021), RBC (day 21, P = 0.008), HCT (day 21, P < 0.001), mean cell hemoglobin (day 14, P = 0.035; day 21, P = 0.003), and serum protein carbonyl level (day 21, P = 0.009), while significantly increased serum GSH content (day 14, P = 0.022; day 28, P = 0.001), SOD and GSH-Px activities at 21 days of age ( P < 0.001 and P = 0.037). The optimal supplemental DL-HMTBA levels in basal diet of broilers aged from 7 to 28 days under low or normal temperatures were similar, so the authors recommended supplemental of DL-HMTBA level was 0.46 %.

  14. Crecimiento inicial de Palo de Rosa (Aniba rosaeodora Ducke en distintos ambientes de fertilidad Growth of initial Rosewood (Aniba rosaeodora Ducke in different environnement of fertility

    Wilmer Herrera Valencia

    2010-12-01

    Full Text Available Los estudios de requerimientos nutricionales son de gran importancia para identificar aquellos más importantes en el desarrollo fisiológico y crecimiento de plántulas. Con el objetivo de evaluar las exigencias nutricionales y los efectos de la omisión de macronutrientes en el crecimiento de plántulas de Aniba rosaeodora; se realizó un experimento en el vivero del INPA-Amazonas-Brasil teniendo como substrato un suelo Podozolico Rojo de baja disponibilidad de nutrientes. Se utilizaron 8 tratamientos bajo la técnica del nutriente faltante: Control (Suelo con macronutrientes, Suelo natural, y la omisión de un macronutriente por vez (-N, -P, -K, -Ca, -Mg, -S. Se evaluaron las siguientes características: tasa de crecimiento relativo (TCR, Tasa de asimilación neta (TAN, peso de la materia seca de la parte aérea (MSPA y de las raíces (MSR, contenido de nutrientes en las hojas, concluyendo que el N, Mg y Ca, demostraron ser limitantes al crecimiento en suelo con pequeña disponibilidad; Las plántulas de A. rosaeodora presentaron un bajo requerimiento nutricional para el P, K y S. La omisión de Ca y N perjudica TCR de la especie. Los elementos más importantes para la MSPA fueron el Ca y el Mg; actuando el Mg más en el área foliar; por otro lado la omisión de azufre favorece la absorción de macronutrientes (N, P, K, Ca, Mg.Studies of nutritional requirements are of great importance for identifying the most important nutrients in physiologic development and seedling growth. A greenhouse pot experiment was conducted at INPA to evaluate the mineral nutritional demands and the effects of macronutrient omission in the plant growth of Aniba rosaeodora Ducke. The following treatments were used: Complete (fertilization with N, P, K, Ca, Mg, S, B and Zn, Standard (nature soil, Complete without N, Complete without P, Complete without K, Complete without Ca, Complete without Mg, and Complete without S. An Ultisoil with low nutrient availability was

  15. Prophylaxis and therapeutic potential of ozone in buiatrics: Current knowledge.

    Đuričić, Dražen; Valpotić, Hrvoje; Samardžija, Marko

    2015-08-01

    Ozone therapy has been in use since 1896 in the USA. As a highly reactive molecule, ozone may inactivate bacteria, viruses, fungi, yeasts and protozoans, stimulate the oxygen metabolism of tissue, treat diseases, activate the immune system, and exhibit strong analgesic activity. More recently, ozone has been used in veterinary medicine, particularly in buiatrics, but still insufficiently. Medical ozone therapy has shown effectiveness as an alternative to the use of antibiotics, which are restricted to clinical use and have been withdrawn from non-clinical use as in-feed growth promoters in animal production. This review is an overview of current knowledge regarding the preventive and therapeutic effects of ozone in ruminants for the treatment of puerperal diseases and improvement in their fertility. In particular, ozone preparations have been tested in the treatment of reproductive tract lesions, urovagina and pneumomovagina, metritis, endometritis, fetal membrane retention and mastitis, as well as in the functional restoration of endometrium in dairy cows and goats. In addition, the preventive use of the intrauterine application of ozone has been assessed in order to evaluate its effectiveness in improving reproductive efficiency in dairy cows. No adverse effects were observed in cows and goats treated with ozone preparations. Moreover, there is a lot of evidence indicating the advantages of ozone preparation therapy in comparison to the application of antibiotics. However, there are certain limitations on ozone use in veterinary medicine and buiatrics, such as inactivity against intracellular microbes and selective activity against the same bacterial species, as well as the induction of tissue inflammation through inappropriate application of the preparation. PMID:26059777

  16. Effects of elevated ozone on CO2 uptake and leaf structure in sugar maple under two light environments

    The interactive effects of ozone and light on leaf structure, carbon dioxide uptake and short-term carbon allocation of sugar maple (Acer saccharum Marsh.) seedlings were examined using gas exchange measurements and 14C-macroautoradiographic techniques. Two-year-old sugar maple seedlings were fumigated from budbreak for 5 months with ambient or 3 × ambient ozone in open-top chambers, receiving either 35% (high light) or 15% (low light) of full sunlight. Ozone accelerated leaf senescence, and reduced net photosynthesis, 14CO2 uptake and stomatal conductance, with the effects being most pronounced under low light. The proportion of intercellular space increased in leaves of seedlings grown under elevated ozone and low light, possibly enhancing the susceptibility of mesophyll cells to ozone by increasing the cumulative dose per mesophyll cell. Indeed, damage to spongy mesophyll cells in the elevated ozone × low light treatment was especially frequent. 14C macroautoradioraphy revealed heterogeneous uptake of 14CO2 in well defined areole regions, suggesting patchy stomatal behaviour in all treatments. However, in seedlings grown under elevated ozone and low light, the highest 14CO2 uptake occurred along larger veins, while interveinal regions exhibited little or no uptake. Although visible symptoms of ozone injury were not apparent in these seedlings, the cellular damage, reduced photosynthetic rates and reduced whole-leaf chlorophyll levels corroborate the visual scaling of whole-plant senescence, suggesting that the ozone × low light treatment accelerated senescence or senescence-like injury in sugar maple. (author)

  17. Impact of greenhouse gases on the Earth's ozone layer

    Zadorozhny, Alexander

    A numerical 2-D zonally averaged interactive dynamical radiative-photochemical model of the ozonosphere including aerosol physics is used to examine the role of the greenhouse gases CO2 , CH4 , and N2 O in the future long-term changes of the Earth's ozone layer, in particular in its recovery after reduction of anthropogenic discharges of chlorine and bromine compounds into the atmosphere. The model allows calculating self-consistently diabatic circulation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the South to North Poles, as well as distribution of sulphate aerosol particles and polar stratospheric clouds (PSCs) of types I and II. The scenarios of expected changes of the anthropogenic pollutants for the period from 1980 through 2050 are taken from Climate Change 2001. The processes, which determine the influence of anthropogenic growth of atmospheric abundance of the greenhouse gases on the dynamics of recovery of the Earth's ozone layer, have been studied in details. Expected cooling of the stratosphere caused by increases of greenhouse gases, most importantly CO2 , essentially influences the ozone layer by two ways: through temperature dependencies of the gas phase reaction rates and through enhancement of polar ozone depletion via increased PSC formation. The model calculations show that a weakness in efficiencies of all gas phase catalytic cycles of the ozone destruction due to cooling of the stratosphere is a dominant mechanism of the impact of the greenhouse gases on the ozone layer in Antarctic as well as at the lower latitudes. This mechanism leads to a significant acceleration of the ozone layer recovery here because of the greenhouse gases growth. On the contrary, the mechanism of the impact of the greenhouse gases on the ozone through PSC modification begins to be more effective in Arctic in comparison with the gas phase mechanism in springs after about 2020, which leads to retard the expected recovery of the

  18. Effect of the slow (K or rapid (k+ feathering gene on body and feather growth and fatness according to ambient temperature in a Leghorn × brown egg type cross

    Bordas André

    2001-11-01

    Full Text Available Abstract Chicks of both sexes issued from the cross of heterozygous K/k+ cocks for the slow-feathering sex linked K allele with k+ (rapid feathering hens, were compared from the age of 4 to 10 weeks at two ambient temperatures. In individual cages, 30 male chicks of each genotype (K/k+ and k+/k+ were raised at 21°C, and 60 others, distributed in the same way, were raised at 31°C. 71 K/W females and 69 k+/W females were raised in a floor pen at 31°C till 10 weeks of age. In the males, the body weight, feed consumption and feed efficiency at different ages were influenced only by temperature (lower growth rate and feed intake at 31°C; no significant effects of the genotype at locus K nor genotype × temperature interaction were observed. In females, all at 31°C, the genotype (K/W or k+/W had no significant effect on growth rate. Plumage weight and weight of abdominal fat (absolute or related to body weight were measured on half of the males of each group in individual cages, at 10 weeks of age. Moreover, on 36 males and 48 females of the two genotypes, in a group battery at 31°C, the absolute and relative weight of plumage were measured on a sample every two weeks between 4 and 10 weeks. In the first case, no significant effect of genotype appeared. In the second case, an interaction between age and genotype was suggested from plumage weight: its growth, especially in male chicks, appears to be temporarily and unexpectedly faster from 4 to 6 weeks of age for the K/k+ and K/W genotypes.

  19. Ozone modeling within plasmas for ozone sensor applications

    Arshak, Khalil; Forde, Edward; Guiney, Ivor

    2007-01-01

    peer-reviewed Ozone (03) is potentially hazardous to human health and accurate prediction and measurement of this gas is essential in addressing its associated health risks. This paper presents theory to predict the levels of ozone concentration emittedfrom a dielectric barrier discharge (DBD) plasma for ozone sensing applications. This is done by postulating the kinetic model for ozone generation, with a DBD plasma at atmospheric pressure in air, in the form of a set of rate equations....

  20. Ozone layer - climate change interactions. Influence on UV levels and UV related effects

    Kelfkens G; Bregman A; de Gruijl FR; van der Leun JC; Piquet A; van Oijen T; Gieskes WWC; Loveren H van; Velders GJM; Martens P; Slaper H; NOP; LPI; LLO

    2002-01-01

    Ozone in the atmosphere serves as a partially protective filter against the most harmful part of the solar UV-spectrum. Decreases in ozone lead to increases in ambient UV with a wide variety of adverse effects on human health, aquatic and terrestrial ecosystems and food chains. Human health effects include the incidence of skin cancer, cataracts and an impairment of the immune system. Ozone depletion has been observed over the past decades, and is most likely caused by man made emissions of h...

  1. Ozone decreases soybean productivity and water use efficiency

    The combination of population growth and climate change will increase pressure on agricultural and water resources throughout this century. An additional consequence of this growth is an increase in anthropogenic emissions that lead to the formation of tropospheric ozone, which in concert with clima...

  2. Impact of ozone on the water relations of ash (Fraxinus excelsior L.)

    Reiner, Susann.

    1996-01-01

    During the field seasons 1993 and 1994, five-year-old field-grown ash trees as well as potted two-year-old saplings and one-year-old seedlings of ash (Fraxinu. g exccl. 5ior L. ) were exposed to ozone episodes in open-top chambers. The plants received either charcoal-filtered air (CF) or charcoal-filtered air to which 150 ppb of ozone were added (CF+03). Plants in unchambered plots, receiving ambient air (Ambient), were included into the investigation for comparison. Half of the two-year-old ...

  3. Children's Models of the Ozone Layer and Ozone Depletion.

    Christidou, Vasilia; Koulaidis, Vasilis

    1996-01-01

    The views of 40 primary students on ozone and its depletion were recorded through individual, semi-structured interviews. The data analysis resulted in the formation of a limited number of models concerning the distribution and role of ozone in the atmosphere, the depletion process, and the consequences of ozone depletion. Identifies five target…

  4. Chemical Coupling Between Atmospheric Ozone and Particulate Matter

    Meng, Z.; DABDUB, D; Seinfeld, J. H.

    1997-01-01

    A major fraction of ambient particulate matter arises from atmospheric gas-to-particle conversion. Attempts to reduce particulate matter levels require control of the same organic and nitrogen oxide (NO_x) emissions that are precursors to urban and regional ozone formation. Modeling of the gas-aerosol chemical interactions that govern levels of particulate components showed that control of gas-phase organic and NO_x precursors does not lead to proportionate reductions of the gas-phase–derived...

  5. Foliar nutrient status of Pinus ponderosa exposed to ozone and acid rain

    A direct effect of foliar exposure to acid rain may be increased leaching of nutrient elements. Ozone exposure, through degradation of the cuticle and cellular membranes, may also result in increased nutrient leaching. To test these hypotheses, the foliar concentrations of 13 nutrient elements were monitored for mature branches of three clones of Pinus ponderosa exposed to ozone and/or acid rain. The three clones represented three distinct levels of phenotypic vigor. Branches were exposed to charcoal filtered, ambient, or 2 x ambient concentrations of ozone and received no acid rain (NAP), pH 5.1 rain (5.1), or pH 3.0 (3.0) rain. Following 10 months of continuous ozone exposure and 3 months of weekly rain applications, the concentrations of P and Mg differed significantly among rain treatments with a ranking of: 5.1 < NAP < 3.0. The S concentration increased with rain application regardless of pH. For the clones of moderate and low vigor, the concentration of N decreased with increasing rain acidity. There was no evidence of significant ozone or ozone x acid rain response. Among the three families, high phenotypic vigor was associated with significantly greater concentrations of N, P, K, Mg, B and An. These results indicate generally negligible leaching as a result of exposure to acid rain and/or ozone for one growing season. Increases in foliar concentrations of S, Mg and P are possibly the result of evaporative surface deposition from the rain solution

  6. Ozone - Current Air Quality Index

    ... more announcements Air Quality Basics Air Quality Index | Ozone | Particle Pollution | Smoke from fires | What You Can ... Partners Kids Movies NAQ Conferences NOAA Older Adults Ozone Particle Pollution (PM2.5, PM10) Publications Publicaciones (En ...

  7. Ozone-depleting Substances (ODS)

    U.S. Environmental Protection Agency — This site includes all of the ozone-depleting substances (ODS) recognized by the Montreal Protocol. The data include ozone depletion potentials (ODP), global...

  8. Air Quality Guide for Ozone

    Local Air Quality Conditions Zip Code: State : My Current Location Air Quality Guide for Ozone Ground-level ozone is one of our nation’s most common air pollutants. Use the chart below to help reduce ...

  9. An Overview of the 2013 Las Vegas Ozone Study (LVOS): Impact of stratospheric intrusions and long-range transport on surface air quality

    A. O. Langford; Senff, C.J.; R.J., Alvarez; Brioude, Jérome; Cooper, O. R; J. S. Holloway; Lin, M.; Marchbanks, R.D.; R. B. Pierce; S. P. Sandberg; A. M. Weickmann; E. J. Williams

    2014-01-01

    International audience The 2013 Las Vegas Ozone Study (LVOS) was conducted in the late spring and early summer of 2013 to assess the seasonal contribution of stratosphere-to-troposphere transport (STT) and long-range transport to surface ozone in Clark County, Nevada and determine if these processes directly contribute to exceedances of the National Ambient Air Quality Standard (NAAQS) in this area. Secondary goals included the characterization of local ozone production, regional transport...

  10. Ozone process insights from field experiments - part I: overview

    Hidy, G. M.

    This paper gives an overview of selected approaches recently adopted to analyze observations from field experiments that characterize the tropospheric physics and chemistry of ozone and related oxidation products. Analysis of ambient oxidant and precursor concentration measurements, combined with meteorological observations, has provided important information about tropospheric processes. Projection of the response of tropospheric ozone concentrations to changes in precursor emissions is achieved through emissions based air quality models (AQMs). These models integrate several "process" elements from source emissions to meteorological and chemical phenomena. Through field campaigns, new knowledge has become available which has enabled workers to better understand the strengths and weaknesses of AQMs and their components. Examples of insightful results include: (a) reconciliation of ambient concentrations of speciated volatile organic compounds (VOCs) with estimates from emissions models, and inventories, (b) verification of chemical mechanisms for ozone formation from its precursors using approximations applicable in different chemical regimes, (c) inference of regimes of sensitivity in ozone concentration to changes in VOC and NO x precursors from ozone management practices, (d) conceptualization of important air mass transport and mixing processes on different spatial and temporal scales that affect ozone and precursor concentrations distributions, and (e) application of the analysis of spatial and temporal variance to infer the origins of chemical product transport, and precursor distributions. Studies from the first category have been used to improve emissions models substantially over previous forms. The remainder of the analyses has yielded valuable insight into the chemical and meteorological mechanisms at work on different spatial and temporal scales. The methods have provided an observationally based framework for effective choices to improve ozone

  11. Interactive effects of ozone and low UV-B radiation on antioxidants in spruce (Picea abies) and pine (Pinus sylvestris) needles

    To study the role of low UV-B radiation in modulating the response of antioxidants to ozone, 4-year-old pine (Pinus sylvestris L.) and spruce (Picea abies L.) seedlings potted in natural soil, were exposed in phytochambers to fluctuating ozone concentrations between 9 and 113 nl 1−1 according to field data recorded at Mt Wank (1175 m above sea level, Bavaria, Germany) and two-times ambient O3 levels. UV-B radiation was either added at a biologically effective level of ca 1.2 kJ m−2 day−1 , which is close to that found in March at Mt Wank, or was excluded by filters (<0.08 kJ m−2 day−1). After one growth phase current-year needles were collected and analysed for antioxidative enzyme activities (superoxide dismutase, SOD, EC 1.15.1.1; catalase, CAT, EC 1.11.1.6; guaiacol peroxidase, POD, EC 1.11.1.7) and soluble antioxidants (ascorbate, glutathione). CAT, POD, ascorbate and glutathione, but not SOD, were increased in needles of both species in response to twice ambient O3 levels. UV-B radiation in the presence of ambient O3 caused an increase in total SOD activity in spruce but had no effects on antioxidants in pine. Twice ambient O3 levels together with low UV-B radiation counteracted the O3-induced increases in ascorbate and CAT in pine but not in spruce. Under these conditions spruce needles showed the highest antioxidative protection and revealed no indication of lipid peroxidation. Pine needles exposed to UV-B and elevated O3 levels showed elevated lipid peroxidation and a 5-fold increase in dehydroascorbate, suggesting that this species was less protected and suffered higher oxidative stress than spruce. (author)

  12. Comparación del crecimiento de Argopecten purpuratus entre cohortes obtenidas de captación de larvas en ambiente natural y de hatchery Comparison of growth among cohorts obtained Argopecten purpuratus larval recruitment in natural and hatchery

    Eduardo P Pérez

    2012-11-01

    Full Text Available En Chile los cultivos del ostión del norte Argopecten purpuratus han sido desarrollados intensivamente a partir de la captación de semillas en ambiente natural y desde principios de 1980 con semillas obtenidas en hatchery. Para aportar información sobre el desempeno de semillas de ostión del norte en este estudio se comparó, mediante ANCOVA, el crecimiento en longitud entre cohortes producidas a partir de semillas de ambiente natural y de hatchery en Tongoy, Chile. Se evaluó la consistencia de esta comparación en distintos anos y estaciones, comparándose parejas de cohortes producidas simultáneamente en los anos 2003 (primavera, 2005 (invierno y 2006 (verano. El análisis estadístico mostró que existen diferencias estadísticas significativas entre cohortes obtenidas en ambiente natural y aquellas obtenidas en hatchery. La prueba de Tukey evidenció diferencias significativas entre CN2003 y CH2003 como también entre CN2005 y CH2005, pero no así entre CN2006 y CH2006. Estas diferencias indican que las cohortes de semillas de ambiente natural crecieron más rápido que las de hatchery. La comparación interanual evidenció diferencias estadísticas significativas. Estos resultados son discutidos a la luz de dos factores: la temperatura de cultivo y la heterocigocidad de la población de cultivo.In Chile crops of the northern scallop Argopecten purpuratus have been developed intensively from seeds obtained in natural environment, and since 1980 from hatchery's seed, when this technique could be controlled and developed. In order to provide information on the performance of seeds of northern scallops in this study growth in length between cohorts produced from seeds obtained in natural environment (CN and hatchery (CH in Tongoy (Chile was compared using ANCOVA. We assessed the consistency of this comparison in different years and seasons. The compared cohorts are pairs of cohorts produced simultaneously in the years 2003 (spring, 2005

  13. Ozonated Olive Oils and Troubles

    Bulent Uysal

    2014-04-01

    Full Text Available One of the commonly used methods for ozone therapy is ozonated oils. Most prominent type of used oils is extra virgin olive oil. But still, each type of unsaturated oils may be used for ozonation. There are a lot of wrong knowledge on the internet about ozonated oils and its use as well. Just like other ozone therapy studies, also the studies about ozone oils are inadequate to avoid incorrect knowledge. Current data about ozone oil and its benefits are produced by supplier who oversees financial interests and make misinformation. Despite the rapidly increasing ozone oil sales through the internet, its quality and efficacy is still controversial. Dozens of companies and web sites may be easily found to buy ozonated oil. But, very few of these products are reliable, and contain sufficiently ozonated oil. This article aimed to introduce the troubles about ozonated oils and so to inform ozonated oil users. [J Intercult Ethnopharmacol 2014; 3(2.000: 49-50

  14. Ozone Therapy in Dentistry

    Ramachandran Sudarshan

    2013-02-01

    Full Text Available With the advancements in the field of dentistry, new treatment protocols are budding day by day to combat human ailments in a much natural better and simpler way. One such advancement is the application of ozone in dentistry. Ozone is a natural element protects us from ultraviolet rays. It has several properties including analgesics, immunostimulant and antimicrobial properties. In Dentistry its uses are abundance from gingival diseases, infection control, temporomandibular disorders, radiation and chemotherapy induced mucositis, lichen planus etc. Researchers believe that this therapy is in state of equilibrium with benefit and drawback. This review throws light on the history, properties, methods of administration, uses in the field of medicine and dentistry, toxicity, contraindications of ozone. [Archives Medical Review Journal 2013; 22(1.000: 45-54

  15. Ozone depletion by hydrofluorocarbons

    Hurwitz, Margaret M.; Fleming, Eric L.; Newman, Paul A.; Li, Feng; Mlawer, Eli; Cady-Pereira, Karen; Bailey, Roshelle

    2015-10-01

    Atmospheric concentrations of hydrofluorocarbons (HFCs) are projected to increase considerably in the coming decades. Chemistry climate model simulations forced by current projections show that HFCs will impact the global atmosphere increasingly through 2050. As strong radiative forcers, HFCs increase tropospheric and stratospheric temperatures, thereby enhancing ozone-destroying catalytic cycles and modifying the atmospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Simulations with the NASA Goddard Space Flight Center 2-D model show that HFC-125 is the most important contributor to HFC-related atmospheric change in 2050; its effects are comparable to the combined impacts of HFC-23, HFC-32, HFC-134a, and HFC-143a. Incorporating the interactions between chemistry, radiation, and dynamics, ozone depletion potentials (ODPs) for HFCs range from 0.39 × 10-3 to 30.0 × 10-3, approximately 100 times larger than previous ODP estimates which were based solely on chemical effects.

  16. Ozonation for source treatment of pharmaceuticals in hospital wastewater - ozone lifetime and required ozone dose

    Hansen, Kamilla Marie Speht; Spiliotopoulou, Aikaterini; Chhetri, Ravi Kumar;

    2016-01-01

    Ozonation aimed at removing pharmaceuticals was studied in an effluent from an experimental pilot system using staged moving bed biofilm reactor (MBBR) tanks for the optimal biological treatment of wastewater from a medical care unit of Aarhus University Hospital. Dissolved organic carbon (DOC) and...... pH in samples varied considerably, and the effect of these two parameters on ozone lifetime and the efficiency of ozone in removing pharmaceuticals were determined. The pH in the effluent varied from 5.0 to 9.0 resulting in approximately a doubling of the required ozone dose at the highest pH for...... each pharmaceutical. DOC varied from 6 to 20 mg-DOC/L. The ozone required for removing each pharmaceutical, varied linearly with DOC and thus, ozone doses normalized to DOC (specific ozone dose) agreed between water samples (typically within 15%). At neutral pH the specific ozone dose required to...

  17. SAGE II Ozone Analysis

    Cunnold, Derek; Wang, Ray

    2002-01-01

    Publications from 1999-2002 describing research funded by the SAGE II contract to Dr. Cunnold and Dr. Wang are listed below. Our most recent accomplishments include a detailed analysis of the quality of SAGE II, v6.1, ozone measurements below 20 km altitude (Wang et al., 2002 and Kar et al., 2002) and an analysis of the consistency between SAGE upper stratospheric ozone trends and model predictions with emphasis on hemispheric asymmetry (Li et al., 2001). Abstracts of the 11 papers are attached.

  18. DEVELOPMENTS IN OZONATION OF WATERS

    Ensar OĞUZ

    2001-03-01

    Full Text Available Ozone, has been used in both industrial and synthetic chemistry. From this point of view, ozone-organic chemistry related papaers have been published by many researcher. Forthermore; its role in air and water pollution problems is more important today. As a result of ozone researches, it is clear that ozone is to be the brightest expection for future in industrial, domestic, and driking water treatment. Ozone, a high grade oxidation matter, has been used for removing the pollutants and toxic materials from waste waters.

  19. Short-term effect of ozone on the pulmonary function of children in primary school.

    Chen, P C; Lai, Y M; Chan, C.C.; Hwang, J. S.; Yang, C Y; Wang, J. D.

    1999-01-01

    The objective of this study was to evaluate the short-term effect of ambient air pollution on the pulmonary function of schoolchildren. We sampled 941 children in primary school in three communities in Taiwan (Sanchun, Taihsi, and Linyuan). The nearby stations of the Taiwan air quality monitoring network provided the hourly ambient concentrations of sulfur dioxide, carbon monoxide, ozone, particulate matter < or = to 10 microm in aerodynamic diameter, and nitrogen dioxide. Spirometry was perf...

  20. Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

    Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures

  1. Seasonal trends in reduced leaf gas exchange and ozone-induced foliar injury in three ozone sensitive woody plant species

    Novak, K. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)]. E-mail: kristopher.novak@wsl.ch; Schaub, M. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Fuhrer, J. [Swiss Federal Research Station for Agroecology and Agriculture FAL, 8046 Zurich (Switzerland); Skelly, J.M. [Department of Plant Pathology, The Pennsylvania State University, University Park, PA 16802 (United States); Hug, C. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Landolt, W. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Bleuler, P. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland); Kraeuchi, N. [Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zuercherstrasse 111, 8903 Birmensdorf (Switzerland)

    2005-07-15

    Seasonal trends in leaf gas exchange and ozone-induced visible foliar injury were investigated for three ozone sensitive woody plant species. Seedlings of Populus nigra L., Viburnum lantana L., and Fraxinus excelsior L. were grown in charcoal-filtered chambers, non-filtered chambers and open plots. Injury assessments and leaf gas exchange measurements were conducted from June to October during 2002. All species developed typical ozone-induced foliar injury. For plants exposed to non-filtered air as compared to the charcoal-filtered air, mean net photosynthesis was reduced by 25%, 21%, and 18% and mean stomatal conductance was reduced by 25%, 16%, and 8% for P. nigra, V. lantana, and F. excelsior, respectively. The timing and severity of the reductions in leaf gas exchange were species specific and corresponded to the onset of visible foliar injury. - Reductions in leaf gas exchange corresponded to the onset of ozone-induced visible foliar injury for seedlings exposed to ambient ozone exposures.

  2. Degradation of Acenaphthene by Ozone

    2007-01-01

    Objective To investigate the oxidation of acenaphthene (Ace), a polycyclic aromatic hydrocarbon (PAH) with a saturated C-C bond by ozone and to characterize the intermediate products of ozonation. Methods Ozone was generated from filtered dry oxygen by an ozone generator and continually bubbled into a reactor containing 1g/L Ace dissolved in an acetonitrile/water solvent mixture (90/10, v/v) at a rate of 0.5 mg/s. HPLC was used to analyze the Ace concentration. Total organic carbon (TOC) was used to measure the amount of water soluble organic compounds. GC-MS was used to identify the ozonized products. Oxygen uptake rate (OUR) of activated sludge was used to characterize the biodegradability of ozonized products. Results During the ozonation process, Ace was degraded, new organic compounds were produced and these intermediate products were difficult mineralize by ozone, with increasing TOC of soluble organics. The ozonized products were degraded by activated sludge more easily than Ace. Conclusion Ozonation decomposes the Ace and improves its biodegradability. The ozonation combined with biological treatment is probably an efficient and economical way to mineralize acenaphthene in wastewater.

  3. SOURCE-SINK BALANCE AND CARBON ALLOCATION BELOW GROUND IN PLANTS EXPOSED TO OZONE

    The role of tropospheric ozone in altering plant growth and development has been the subject of thousands of publications over the last several decades. Still, there is limited understanding regarding the possible effects of ozone on soil processes. In this review, the effects ...

  4. 13C/12C ratios as indicators of plant physiological response to ozone and simulated acid rain

    This paper summarizes work performed to assess the effects of ozone and acid rain on growth, gas exchange and water use efficiency of shortleaf pine (Pinus echinata). The results suggest that stem diameter, leaf area and leaf biomass are significantly reduced by exposure to elevated ozone concentrations but that acid rain has no effect on any of the growth measurements. 3 refs, 2 figs

  5. Introduction to working group on tropospheric ozone, Health Effects Institute environmental epidemiology planning project.

    Tager, I B

    1993-01-01

    The working group on tropospheric ozone of the Health Effects Institute has evaluated the need for epidemiologic studies on the health effects of ozone (O3) exposure. This paper summarizes current data and identifies possible research questions. The extent to which ozone exposure results in chronic health effects is largely undefined and is the central issue for epidemiologic studies. Most current data focus on transient endpoints; the link between acute changes in symptoms and/or lung function and possible chronic effects has not been established. Concepts of ozone-induced health effects have been extended to include processes of chronic disease (e.g., markers of ongoing inflammation and repair, markers of accelerated lung aging). Traditional epidemiologic studies performed have focused only on accelerated lung aging and are limited by a number of methodologic problems. Recent, very preliminary, studies suggest new opportunities for the use of human lung tissue and a variety biological response markers as part of epidemiologic studies. The identification of sensitive subpopulations with regard to ozone-induced health effects has been studied incompletely and is important both in terms of study efficiency and mechanistic insight. Methodologic advances in the reconstruction of past ozone exposure are seen as essential, as is the incorporation of emerging markers of biologic response to ozone into traditional epidemiologic study designs. Finally, more data on the joint and independent contribution of other ambient air pollutants to putative ozone-induced health effects is warranted. PMID:8206032

  6. Catalytic decomposition of low level ozone with gold nanoparticles supported on activated carbon

    Pengyi ZHANG; Bo ZHANG; Rui SHI

    2009-01-01

    Highly dispersed gold nanoparticles were supported on coal-based activated carbon (AC) by a sol immobilization method and were used to investigate their catalytic activity for low-level ozone decomposition at ambient temperature. Nitrogen adsorption-desorption,scanning electron microscope (SEM), and X-ray photo-electron spectroscopy (XPS) were used to characterize the catalysts before and after ozone decomposition. The results showed that the supported gold nanoparticles prepared with microwave heating were much smaller and more uniformly dispersed on the activated carbon than those prepared with traditional conduction heating, exhibiting higher catalytic activity for ozone decomposition. The pH values of gold precursor solution significantly influenced the catalytic activity of supported gold for ozone decomposition, and the best pH value was 8. In the case of space velocity of 120000 h-1, inlet ozone concentration of 50mg/m3, and relative humidity of 45%, the Au/AC catalyst maintained the ozone removal ratio at 90.7% after 2500 min. After being used for ozone decomposition, the surface carbon of the catalyst was partly oxidized and the oxygen content increased accordingly, while its specific surface area and pore volume only decreased a little.Ozone was mainly catalytically decomposed by the gold nanoparticles supported on the activated carbon.

  7. Ozone: apocalypse or misinformation

    This paper debates about the origin of the destruction of ozone layer in the stratosphere. Chlorofluorocarbons don't seem to be the single responsible agent but chloric acid from volcanic eruptions, chlorinated compounds of oceans or biomass combustion are another major sources. 13 refs., 3 figs

  8. Ozone, greenhouse effect

    This file is made of eight general papers on environment (climates under observation, research on photo-oxidizing pollution, scientific aspects of stratospheric ozone layer, urban engineering and environment, glory of public gardens, earths not very natural, darwinism and society, economical data on environment). (A.B.). refs., 3 tabs

  9. Role of neutrophilic inflammation in ozone-induced epithelial alterations in the nasal airways of rats

    Cho, Hye Youn

    Ozone is a principal oxidant air pollutant in photochemical smog. Epithelial cells lining the centriacinar region of lung and the proximal aspects of nasal passage are primary target sites for ozone-induced injury in laboratory animals. Acute exposure of rats to high ambient concentrations of ozone (e.g., 0.5 ppm) results in neutrophilic inflammation, epithelial hyperplasia and mucous cell metaplasia (MCM) in the nasal transitional epithelium (NTE) lining the proximal nasal airways. The principal purpose of the present study was to investigate the role of pre-metaplastic cellular responses, especially neutrophilic inflammation, in the pathogenesis of ozone-induced MCM in rat NTE. For this purpose, three specific hypotheses-based whole-animal inhalation studies were conducted. Male F344/N rats were exposed in whole-body inhalation chambers to 0 (filtered air) or 0.5 ppm ozone for 1-3 days (8 h/day). Histochemical, immunochemical, molecular and morphometric techniques were used to investigate the ozone-induced cellular and molecular events in the NTE. Two in vitro studies were also conducted to examine the effects of ozone-inducible cytokines (i.e., tumor necrosis factor-alpha; TNF- a, and interleukin-6; IL-6) on mucin gene (rMuc-5AC) expression. Ozone induced a rapid increase of rMuc-5AC mRNA in nasal tissues within hours after the start of exposure. It preceded the appearance of MCM, and persisted with MCM. Ozone-induced neutrophilic inflammation accompanied the mucin gene upregulation, but was resolved when MCM first appeared in the NTE. Antibody-mediated depletion of circulating neutrophils attenuated ozone-induced MCM, although it did not affect the ozone-induced epithelial hyperplasia and mucin mRNA upregulation. In another study, it was found that preexisting neutrophilic rhinitis induced by endotoxin augmented the ozone-induced MCM. However, pre-existing rhinitis did not alter the severity of ozone-induced epithelial hyperplasia and mucin gene upregulation

  10. A 15-year climatology of wind pattern impacts on surface ozone in Houston, Texas

    Souri, Amir Hossein; Choi, Yunsoo; Li, Xiangshang; Kotsakis, Alexander; Jiang, Xun

    2016-06-01

    Houston is recognized for its large petrochemical industrial facilities providing abundant radicals for tropospheric ozone formation. Fortunately, maximum daily 8-h average (MDA8) surface ozone concentrations have declined in Houston (- 0.6 ± 0.3 ppbv yr- 1) during the summers (i.e., May to September) of 2000 to 2014, possibly due to the reductions in precursor emissions by effective control policies. However, it is also possible that changes in meteorological variables have affected ozone concentrations. This study focused on the impact of long-term wind patterns which have the highest impact on ozone in Houston. The analysis of long-term wind patterns can benefit surface ozone studies by 1) providing wind patterns that distinctly changed ozone levels, 2) investigating the frequency of patterns and the respective changes and 3) estimating ozone trends in specific wind patterns that local emissions are mostly involved, thus separating emissions impacts from meteorology to some extent. To this end, the 900-hPa flow patterns in summers of 2000 to 2014 were clustered in seven classes (C1-C7) by deploying an unsupervised partitioning method. We confirm the characteristics of the clusters from a backward trajectory analysis, monitoring networks, and a regional chemical transport model simulation. The results indicate that Houston has experienced a statistically significant downward trend (- 0.6 ± 0.4 day yr- 1) of the cluster of weak easterly and northeasterly days (C4), when the highest fraction of ozone exceedances (MDA8 > 70 ppbv) occurred. This suggests that the reduction in ozone precursors was not the sole reason for the decrease in ozone exceedance days (- 1.5 ± 0.6 day yr- 1). Further, to examine the efficiency of control policies intended to reduce the amount of ozone, we estimated the trend of MDA8 ozone in C4 and C5 (weak winds) days when local emissions are primarily responsible for high ambient ozone levels. Both C4 and C5 show a large reduction in the

  11. Effect of regular aerobic exercise with ozone exposure on peripheral leukocyte populations in Wistar male rats

    Afshar Jafari

    2009-09-01

    Full Text Available

    • BACKGROUND: The immune system in endurance athletes may be at risk for deleterious effects of gasous pollutants such as ambient ozone. Therefore, this study was performed to assess the effect of regular aerobic exercise with ozone exposure on peripheral leukocytes populations in male Wistar rats.
    • METHODS: Twenty eight 8 weeks old rats were selected and randomly divided into four groups of ozone-unexposed anduntrained (control or group 1, n = 6, ozone-exposed and untrained (group 2, n = 6, ozone-unexposed and trained (group 3, n = 8, ozone-exposed and trained (group 4, n = 8. All animals in groups 3 and 4 were regularly running (20 m/min, 30 min/day on a treadmill for 7 weeks (5 day/week. After the last ozone exposure [0.3 ppm, 30 min per sessions], blood samples were obtained from the cardiac puncture and hematological parameters as well as blood lactate were measured using automatic analyzers. Data were expressed as means (± SD and analyzed by ANOVA and Pearson's correlation tests at p < 0.05.
    • RESULTS: All the hematological parameters differences (except RBC and hemoglobin rate were significantly higher in the trained groups (p < 0.001. However, ozone-induced leukocytosis in the trained (but not in the sedentary rats was statistically higher than in the counterpart groups.
    • CONCLUSIONS: Repeated acute ozone exposure has more additive effect on peripheral leukocyte counts in active animals. But, more researches are needed to identify effects of ozone exposure on other components of the immune system in athletes and non-athletes.
    • KEYWORDS: Moderate Aerobic Exercise, Ozone Exposure,  eukocytosis, Wistar Rats.

  12. Non-Thermal Plasma Ozone Generation

    S. Pekárek

    2003-01-01

    Full Text Available This paper reviews ozone properties, ozone applications and the mechanism of ozone production in non-thermal plasma. An analysis is made of the influence of a reduced electric field and discharge space temperature on ozone production. The phenomenon of discharge poisoning is also explained. Finally, a modern ozone production system based on dielectric barrier electrical discharge is described.

  13. Non-Thermal Plasma Ozone Generation

    S. Pekárek

    2003-01-01

    This paper reviews ozone properties, ozone applications and the mechanism of ozone production in non-thermal plasma. An analysis is made of the influence of a reduced electric field and discharge space temperature on ozone production. The phenomenon of discharge poisoning is also explained. Finally, a modern ozone production system based on dielectric barrier electrical discharge is described.

  14. Ambient air quality trends in Alberta

    This document provided an overview of ambient air pollutant trends in Alberta. The report discussed the following pollutants having effect on human and environmental health: carbon monoxide (CO), hydrogen sulphide (H2S), nitrogen dioxide (NO2), sulphur dioxide (SO2), ozone (O3), fine particulate matter (PM2.5), benzene, and benzopyrene. Each of these pollutants was described. The report provided data on annual average concentration trends and annual 99th percentile concentration as an indicator of peak concentrations. A map illustrating air quality monitoring stations in 2006 was also provided. The findings revealed that mean annual CO levels were the lowest they have been since 1990; hydrogen sulphide concentrations have fluctuated in time since 1990; most Edmonton and Calgary area stations showed significant decreasing trends in annual average NO2 levels since 1990; and higher SO2 concentrations have been found in the industrial areas of Alberta, such as the Redwater and Scotford oil sands locations. tabs., figs

  15. On the impact of temperature on tropospheric ozone concentration levels in urban environments

    E Stathopoulou; G Mihalakakou; M Santamouris; H S Bagiorgas

    2008-06-01

    The influence of temperature on tropospheric ozone (O3)concentrations in urban and photochemically polluted areas in the greater Athens region are investigated in the present study.Hourly values of the ambient air temperature used for studying the urban heat island effect in Athens were recorded at twenty-three experimental stations while ozone concentration values were measured at three of the above-mentioned stations and for a period of two years (1996 –1997).The linear correlation between ozone concentration and air temperature values as well as the temporal variation of temperature and ozone concentration,for the above-mentioned experimental stations, were calculated and analysed.Moreover,a neural network approach was used for investigating the impact of temperature on the ozone concentration values over the greater Athens area.The neural network model used ambient air temperature as one of its input parameters and it was found that temperature is a predominant parameter,affecting considerably the ozone concentration values.

  16. Ozone air pollution and foliar injury development on native plants of Switzerland

    Novak, Kristopher; Skelly, John M.; Schaub, Marcus; Kraeuchi, Norbert; Hug, Christian; Landolt, Werner; Bleuler, Peter

    2003-09-01

    Visible ozone-induced foliar injury on native forest species of Switzerland was identified and confirmed under ambient OTC-conditions and related to the current European AOT40 standard. - The objectives of this study were to examine the foliar sensitivity to ozone exposure of 12 tree, shrub, and herbaceous species native to southern Switzerland and determine the seasonal cumulative ozone exposures required to induce visible foliar injury. The study was conducted from the beginning of May through the end of August during 2000 and 2001 using an open-top chamber research facility located within the Lattecaldo Cantonal Forest Nursery in Canton Ticino, southern Switzerland (600 m asl). Plants were examined daily and dates of initial foliar injury were recorded in order to determine the cumulative AOT40 ppb h ozone exposure required to cause visible foliar injury. Plant responses to ozone varied significantly among species; 11 species exhibited visible symptoms typical of exposures to ambient ozone. The symptomatic species (from most to least sensitive) were Populus nigra, Viburnum lantana, Salix alba, Crataegus monogyna, Viburnum opulus, Tilia platyphyllos, Cornus alba, Prunus avium, Fraxinus excelsior, Ribes alpinum, and Tilia cordata; Clematis spp. did not show foliar symptoms. Of the 11 symptomatic species, five showed initial injury below the critical level AOT40 10 ppmh O{sub 3} in the 2001 season.

  17. Incidence of ozone symptoms on vegetation within a National Wildlife Refuge in New Jersey, USA

    During 1993-1996 and 2001-2003, we evaluated the percentage of plants (incidence) exhibiting ozone-induced foliar symptoms on vegetation within a National Wildlife Refuge located along the Atlantic Ocean coast of New Jersey, USA. Incidence varied among plant species and years. Bioindicator plants most sensitive to ozone, across all years, included native common milkweed (Asclepias syriaca) and wild grape (Vitis spp.), as well as introduced tree-of-heaven (Ailanthus altissima). Less sensitive bioindicators included Virginia creeper (Parthenocissus quinquefolia) and winged sumac (Rhus coppolina). Black cherry (Prunus serotina) and sassafras (Sassafras albidum) were least sensitive. The greatest incidence of ozone symptoms, across all plant species, occurred in 1996, followed by 2001 > 1995 > 1994 > 1993 > 2003 > 2002. A model was developed that showed a statistically significant relationship between incidence of ozone symptoms and the following parameters: plant species, Palmer Drought Severity Index, and the interaction of W126 x N100 measures of ambient ozone. - Vegetation in a National Wildlife Refuge containing a Class I wilderness area exhibits foliar symptoms from ambient ozone

  18. A network of autonomous surface ozone monitors in Antarctica: technical description and first results

    Bauguitte, S. J.-B.; Brough, N.; Frey, M. M.; Jones, A. E.; Maxfield, D. J.; Roscoe, H. K.; Rose, M. C.; Wolff, E. W.

    2011-04-01

    A suite of 10 autonomous ozone monitoring units, each powered using renewable energy, was developed and built to study surface ozone in Antarctica during the International Polar Year (2007-2009). The monitoring systems were deployed in a network around the Weddell Sea sector of coastal Antarctica with a transect up onto the Antarctic Plateau. The aim was to measure for a full year, thus gaining a much-improved broader view of boundary layer ozone seasonality at different locations as well as of factors affecting the budget of surface ozone in Antarctica. Ozone mixing ratios were measured based on UV photometry using a modified version of the commercial 2B Technologies Inc. Model 202 instrument. All but one of the autonomous units measured successfully within its predefined duty cycle throughout the year, with some differences in performance dependent on power availability and ambient temperature. Mean data recovery after removal of outliers was on average 70% (range 44-83%) and precision varied between 1.5 and 8 ppbv, thus was sufficiently good to resolve year-round the main ozone features of scientific interest. We conclude that, with adequate power, and noting a minor communication problem, our units would be able to operate successfully at ambient temperatures down to -60 °C. Systems such as the one described in this paper, or derivatives of it, could therefore be deployed either as local or regional networks elsewhere in the Arctic or Antarctic. Here we present technical information and first results from the experiment.

  19. Ozone air pollution and foliar injury development on native plants of Switzerland

    Visible ozone-induced foliar injury on native forest species of Switzerland was identified and confirmed under ambient OTC-conditions and related to the current European AOT40 standard. - The objectives of this study were to examine the foliar sensitivity to ozone exposure of 12 tree, shrub, and herbaceous species native to southern Switzerland and determine the seasonal cumulative ozone exposures required to induce visible foliar injury. The study was conducted from the beginning of May through the end of August during 2000 and 2001 using an open-top chamber research facility located within the Lattecaldo Cantonal Forest Nursery in Canton Ticino, southern Switzerland (600 m asl). Plants were examined daily and dates of initial foliar injury were recorded in order to determine the cumulative AOT40 ppb h ozone exposure required to cause visible foliar injury. Plant responses to ozone varied significantly among species; 11 species exhibited visible symptoms typical of exposures to ambient ozone. The symptomatic species (from most to least sensitive) were Populus nigra, Viburnum lantana, Salix alba, Crataegus monogyna, Viburnum opulus, Tilia platyphyllos, Cornus alba, Prunus avium, Fraxinus excelsior, Ribes alpinum, and Tilia cordata; Clematis spp. did not show foliar symptoms. Of the 11 symptomatic species, five showed initial injury below the critical level AOT40 10 ppmh O3 in the 2001 season

  20. Studies on the Biological Effects of Ozone: 10. Release of Factors from Ozonated Human Platelets

    G. Valacchi

    1999-01-01

    Full Text Available In a previous work we have shown that heparin, in the presence of ozone (O3, promotes a dose-dependent platelet aggregation, while after Ca2+ chelation with citrate, platelet aggregation is almost negligible. These results led us to think that aggregation may enhance the release of platelet components. We have here shown that indeed significantly higher amount of platelet-derived growth factor (PDGF, transforming growth factor β1 (TGF-β1 and interleukin-8(IL-8 are released in a dose-dependent manner after ozonation of heparinised platelet-rich plasma samples. These findings may explain the enhanced healing of torpid ulcers in patients with chronic limbischemia treated with O3 autohaemoteraphy (O3-AHT.

  1. Modelling of long-term anthropogenic changes in stratospheric temperature and the ozone layer

    Complete text of publication follows. A numerical two-dimensional interactive dynamical-radiative-photochemical model including aerosol physics is used to examine the expected long-term changes in stratospheric temperature and the Earth's ozone layer due to anthropogenic pollution of the atmosphere by the greenhouse gases CO2, CH4, N2O and by ozone-depleting chlorine and bromine compounds. The model time-dependent runs were made for the period from 1975 to 2050. The mechanisms of the impact of each of the pollutants on stratospheric temperature have been analysed, their relative contributions to the predicted temperature change have been estimated. The processes, which determine the influence of anthropogenic growth of atmospheric abundance of the greenhouse gases on the dynamics of recovery of the Earth's ozone layer after reduction of anthropogenic discharges of ozone-depleting chlorine and bromine compounds into the atmosphere, have been studied in details. The contributions of different pollutions to the predicted ozone changes have been estimated. The results of the calculations show that the basic mechanism by which greenhouse gases influence the ozone layer is stratospheric cooling accompanied by a weakness in the efficiency of the catalytic cycles of ozone destruction due to temperature dependencies of the photochemical gas-phase reactions. Modification of polar stratospheric clouds (PSCs) caused by anthropogenic growth of the greenhouse gases is important only for the polar ozone. An essential influence of the greenhouse gases on the ozone by a modification of the stratospheric sulphate aerosol is revealed. The aerosol changes caused by the greenhouse gases modify the distribution of the ozone-active gaseous chlorine, bromine and nitrogen components by means of heterogeneous reactions on the aerosol surface, resulting in a significant decrease in springtime polar ozone depletion of the Antarctic ozone hole.

  2. ATMOSPHERIC VOLATILE ORGANIC COMPOUND MEASUREMENTS DURING THE 1996 PASO DEL NORTE OZONE STUDY

    Ambient air VOC samples were collected at surface air quality monitoring sites, near sources of interest, and aloft on the US (El Paso) and Mexican (Ciudad Juarez) side of the border during a six-week period of the 1996 Paso del Norte Ozone Study. Samples were collected at five...

  3. Evaluation of DNA dosimetry to assess ozone-mediated variability of biologically harmful radiation in Antarctica

    George, AL; Peat, HJ; Buma, AGJ

    2002-01-01

    In this study we investigated the use of a DNA dosimeter to accurately measure changes in ultraviolet B radiation (UVBR; 280-315 nm) under Antarctic ozone hole conditions. Naked DNA solution in quartz tubes was exposed to ambient solar radiation at Rothera Research Station, Antarctica, between Octob

  4. Effects of combinations of diesel exhaust and ozone exposure on lung function in human volunteers.

    Ozone (03) exposure induces changes in human lung function, typically seen as a decrease in forced expiratory volume in one sec (FEV1) and forced vital capacity (FVC). Because people are usually exposed to other ambient air pollutants simultaneously with 03, there may be interact...

  5. Diesel Exhaust Modulates Ozone-induced Lung Function Decrements in Healthy Human Volunteers

    The potential effects of combinations of dilute whole diesel exhaust (DE) and ozone (03), each a common component of ambient airborne pollutant mixtures, on lung function were examined. Healthy young human volunteers were exposed for 2 hr to pollutants while exercising (~50 L/min...

  6. Estimating changes in urban ozone concentrations due to life cycle emissions from hydrogen transportation systems

    Hydrogen has been proposed as a low polluting alternative transportation fuel that could help improve urban air quality. This paper examines the potential impact of introducing a hydrogen-based transportation system on urban ambient ozone concentrations. This paper considers two scenarios, where significant numbers of new hydrogen vehicles are added to a constant number of gasoline vehicles. In our scenarios hydrogen fuel cell vehicles (HFCVs) are introduced in Sacramento, California at market penetrations of 9% and 20%. From a life cycle analysis (LCA) perspective, considering all the emissions involved in producing, transporting, and using hydrogen, this research compares three hypothetical natural gas to hydrogen pathways: (1) on-site hydrogen production; (2) central hydrogen production with pipeline delivery; and (3) central hydrogen production with liquid hydrogen truck delivery. Using a regression model, this research shows that the daily maximum temperature correlates well with atmospheric ozone formation. However, increases in initial VOC and NOx concentrations do not necessarily increase the peak ozone concentration, and may even cause it to decrease. It is found that ozone formation is generally limited by NOx in the summer and is mostly limited by VOC in the fall in Sacramento. Of the three hydrogen pathways, the truck delivery pathway contributes the most to ozone precursor emissions. Ozone precursor emissions from the truck pathway at 9% market penetration can cause additional 3-h average VOC (or NOx) concentrations up to approximately 0.05% (or 1%) of current pollution levels, and at 20% market penetration up to approximately 0.1% (or 2%) of current pollution levels. However, all of the hydrogen pathways would result in very small (either negative or positive) changes in ozone air quality. In some cases they will result in worse ozone air quality (mostly in July, August, and September), and in some cases they will result in better ozone air quality

  7. Responses of sensitive and tolerant bush beans (Phaseolus vulgaris L.) to ozone in open-top chambers are influenced by phenotypic differences, morphological characteristics, and the chamber environment

    Elagoez, Vahram [Plant Biology Graduate Program, University of Massachusetts, Amherst, MA 01003 (United States)]. E-mail: velagoz@nsm.umass.edu; Manning, William J. [Department of Plant, Soil and Insect Sciences, University of Massachusetts, Amherst, MA 01003 (United States)

    2005-08-15

    Responses of bush bean (Phaseolus vulgaris L.) lines 'S156' (O{sub 3}-sensitive) and 'R123' (O{sub 3}-tolerant), and cultivars 'BBL 290' (O{sub 3}-sensitive) and 'BBL 274' (O{sub 3}-tolerant) to ambient ozone (O{sub 3}) were investigated during the 2001 and 2002 growing seasons. Seedlings were grown in pots inside open-top chambers (OTCs), with charcoal filtered (CF) and non-filtered (NF) ambient air, and in non-chambered ambient air (AA) plots. Growth parameters from individual plants were evaluated after harvests at the end of vegetative (V{sub 4}) and reproductive (R{sub 10}) growth phases. Results at V{sub 4} indicated that CF did not provide additional benefits over NF in 'S156' in 2001 and 2002. In contrast, exposure to CF significantly impaired the growth of 'R123'. At the end of R{sub 10}, 'S156' produced more pods, most of which remained immature, and contained fewer seeds or were more frequently aborted, whereas pods produced in 'R123' reached pod maturation and senescence more consistently. Despite increased seed weights inside the OTCs, as observed in 'S156', differences between the two lines were insignificant when grown outside OTCs. Results from the 'BBL 290'/'BBL 274' pair, especially at V{sub 4} phase, remained inconclusive. Plant morphological characteristics, variabilities in environmental conditions, and 'chamber effects' inside OTCs were influential in determining plant response to ambient O{sub 3}. - Phenotypic differences, morphological characteristics, and 'chamber effects' inside OTCs are equally influential in determining the responses of beans to O{sub 3}.

  8. Ozone production in summer in the megacities of Tianjin and Shanghai, China: a comparative study

    L. Ran

    2012-08-01

    Full Text Available Rapid economic growth has given rise to a significant increase in ozone precursor emissions in many regions of China, especially in the densely populated North China Plain (NCP and Yangtze River Delta (YRD. Improved understanding of ozone formation in response to different precursor emissions is imperative to address the highly nonlinear ozone problem and to provide a solid scientific basis for efficient ozone abatement in these regions. A comparative study on ozone photochemical production in summer has thus been carried out in the megacities of Tianjin (NCP and Shanghai (YRD. Two intensive field campaigns were carried out respectively at an urban and a suburban site of Tianjin, in addition to routine monitoring of trace gases in Shanghai, providing data sets of surface ozone and its precursors including nitrogen oxides (NOx and various non-methane hydrocarbons (NMHCs. Ozone pollution in summer was found to be more severe in the Tianjin region than in the Shanghai region, based on either the frequency or the duration of high ozone events. Such differences might be attributed to the large amount of highly reactive NMHCs in Tianjin. Industry related species like light alkenes were of particular importance in both urban and suburban Tianjin, while in Shanghai aromatics dominated. In general, the ozone problem in Shanghai is on an urban scale. Stringent control policies on local emissions would help reduce the occurrence of high ozone concentrations. By contrast, ozone pollution in Tianjin is probably a regional problem. Combined efforts to reduce ozone precursor emissions on a regional scale must be undertaken to bring the ozone problem under control.

  9. Estimation of risk of glucose 6-phosphate dehydrogenase-deficient red cells to ozone and nitrogen dioxide. Research report (Final) 1 June 1983-30 November 1984

    Amoruso, M.A.

    1985-01-01

    The African variant of glucose 6-phosphate dehydrogenase deficiency (G6PD, A variant) is a sex-linked inheritable enzyme deficiency which affects approximately 14% of black males and 2% of black females in the United States. Dr. E.J. Calabrese et al., working with extrapolations of data from published literature, has hypothesized that inhaled ozone might significantly decrease glutathione levels in G6PD-deficient erythrocytes, and therefore, that affected individuals might be at risk for significant hematologic effects due to inhalation of ambient levels of ozone or other oxidant species. The study tests the hypothesis that exposure of G6PD-deficient erythrocytes to ambient levels of ozone and nitrogen dioxide will result in a significant decrease in intracellular glutathione levels and/or the formation of Heinz bodies. Results suggest that there is small likelihood that ambient levels of ozone and nitrogen dioxide will produce significant oxidant stress in G6PD-deficient individuals.

  10. Residential indoor air quality guideline : ozone

    Ozone (O3) is a colourless gas that reacts rapidly on surfaces and with other constituents in the air. Sources of indoor O3 include devices sold as home air cleaners, and some types of office equipment. Outdoor O3 is also an important contributor to indoor levels of O3, depending on the air exchange rate with indoor environments. This residential indoor air quality guideline examined factors that affect the introduction, dispersion and removal of O3 indoors. The health effects of prolonged exposure to O3 were discussed, and studies conducted to evaluate the population health impacts of O3 were reviewed. The studies demonstrated that there is a significant association between ambient O3 and adverse health impacts. Exposure guidelines for residential indoor air quality were discussed. 14 refs.

  11. Long-term Measurements of Summer-time Ozone at the Walnut Grove Tower - Understanding Trends in the Boundary Layer

    Mahmud, A.; Di, P.; Mims, D.; Avise, J.; DaMassa, J.; Kaduwela, A. P.

    2015-12-01

    The California Air Resources Board (CARB) has been monitoring boundary layer ozone at the Walnut Grove Tower (WGT) since 1996 for investigating regional transport and vertical profile. Walnut Grove is located between Sacramento and Stockton, CA in the Sacramento - San Joaquin Delta. Sampling inlets are positioned at 30-ft, 400-ft, 800-ft, 1200-ft and 1600-ft levels of the 2000-ft tower, which is one of the tallest monitoring towers in the Western US. Ozone, ambient temperature, wind speed, and wind direction are simultaneously measured at each level, and reported as hourly averages. The current study included analyses of available ozone and corresponding meteorological data for the months of June - September from 1996 - 2014 with objectives to: 1) explore trends and inter-annual variability of ozone, 2) examine any correlations between ozone and meteorological parameters, 3) understand interactions of ozone measured at various levels, and 4) assess how well a regulatory state-of-the-science air quality model such as the Community Multi-scale Air Quality Model (CMAQ) captures observation. Daily 1-hr maximum ozone has been consistently decreasing during the 1996 - 2014 period at a rate of ~1 ppb per year. This indicates that CARB's measures to control ambient ozone have been effective over the past years. Evolution of the vertical profile throughout the day shows that ozone is fairly homogeneously mixed between 1 - 5 pm, when mixing height typically reaches the maximum. Ozone at 30-ft shows the greatest variability because of its proximity to the ground and emissions sources - rises faster during morning hours (7 - 10 am) and declines more rapidly during evening hours (7 - 10 pm) compared to other levels. Air masses reaching the tower are predominantly southwesterly (247 - 257 deg.) at the bottom, and southwesterly to slightly northwesterly (254 - 302 deg.) at top levels. Daily 1-hr maximum ozone was negatively correlated with wind speed (i.e. ozone was high under

  12. Ozonated olive oils and the troubles.

    Uysal, Bulent

    2014-01-01

    One of the commonly used methods for ozone therapy is ozonated oils. Most prominent type of used oils is extra virgin olive oil. But still, each type of unsaturated oils may be used for ozonation. There are a lot of wrong knowledge on the internet about ozonated oils and its use as well. Just like other ozone therapy studies, also the studies about ozone oils are inadequate to avoid incorrect knowledge. Current data about ozone oil and its benefits are produced by supplier who oversees financial interests and make misinformation. Despite the rapidly increasing ozone oil sales through the internet, its quality and efficacy is still controversial. Dozens of companies and web sites may be easily found to buy ozonated oil. But, very few of these products are reliable, and contain sufficiently ozonated oil. This article aimed to introduce the troubles about ozonated oils and so to inform ozonated oil users. PMID:26401346

  13. Health Effects of Ozone and Particle Pollution

    ... Health Risks Health Effects of Ozone and Particle Pollution Two types of air pollution dominate in the ... So what are ozone and particle pollution? Ozone Pollution It may be hard to imagine that the ...

  14. Depletion of ozone layer and health

    A decrease in food supply, rather than an increase in cancers, could turn out to be the greatest danger from the loss of the Earth's ozone shield says the author. This could result from alterations in plants and animals that are more sensitive than humans to increased levels of ultraviolet radiation. Increasing ambient ultraviolet radiation within a short time would exert dramatic selective pressure on all living organisms, but the global consequences of such an occurrence cannot be predicted. Common skin cancer is the best understood link with ultraviolet radiation. In fact, the link is so straightforward that precise calculations are possible: a 1% decrease in ozone equals a 2% increase in ultraviolet radiation, which translates into a 3 to 6% increase in common skin cancers in the US. If the immune system is damaged, the body cannot survive the continual onslaught of infectious agents present in the environment. People's willingness to protect themselves against sunlight exposure has been dictated by fashion. The fashionability of hats and sunglasses is beneficial for reducing the risk of cataracts; on the other hand, the fashionability of sun-tans has probably contributed to the rising incidence of skin cancer among Caucasians. The best remedy she advises is to avoid overexposure to sunlight

  15. FEASIBILITY STUDY OF USING OZONE FOR PRESEEDING PROCESSING OF CORN SEEDS

    Shevchenko A. A.; Saprunova E. A.; Mumro A. A.

    2014-01-01

    The feasibility study on use of ozone and air mix as a preseeding stimulator of growth processes of seeds of corn is presented in the article. The comparative analysis of the standard and offered technologies has been also provided

  16. Ozonation followed by ultraviolet irradiation provides effective bacteria inactivation in a freshwater recirculating system

    Recirculating aquaculture systems may require an internal disinfection process to control population growth of pathogens and heterotrophic bacteria. Ozonation and ultraviolet (UV) irradiation are two technologies that have been used to treat relatively large aquaculture flows, including flows withi...

  17. Ringrotbestrijding met behulp van ozon

    Wolf, de, H.; Bergervoet, J.H.W.; Kastelein, P.; Zouwen, van der, P.S.

    2009-01-01

    Door het kistenreinigingsbedrijf van Frans Renne wordt een nieuwe kistenreinigingsmachine ontwikkeld. De methode is gebaseerd op ontsmetting met Ozon van recirculerend spoelwater en van kisten. In dit rapport wordt verslag gedaan van laboratorium-onderzoek naar het effect van ozon op ringrotbacterieën en de noodzakelijke dosering en inwerktijd, en naar het effect van ozon in organisch belast (maar d.m.v. filtering gereinigd) spoelwater

  18. Extrapolating future Arctic ozone losses

    Knudsen, B. M.; Harris, N. R. P.; S. B. Andersen; Christiansen, B.; N. Larsen; Rex, M.; B. Naujokat

    2004-01-01

    Future increases in the concentration of greenhouse gases and water vapour may cool the stratosphere further and increase the amount of polar stratospheric clouds (PSCs). Future Arctic PSC areas have been extrapolated from the highly significant trends 1958-2001. Using a tight correlation between PSC area and the total vortex ozone depletion and taking the decreasing amounts of ozone depleting substances into account we make empirical estimates of future ozone. The result...

  19. An investigation of ambient gameplay

    Eyles, Mark

    2012-01-01

    Inspired by Brian Eno's ambient music, which is persistent and supports different levels of engagement, this research explores ambient gameplay in computer, video and pervasive games. Through the creation of original games containing ambient gameplay and looking for ambient gameplay in existing commercial games, this research focuses on gameplay that supports a range of depths of player engagement. This research is not concerned with ambient intelligent environments or other technologies that...

  20. Transcriptional signatures in leaves of adult European beech trees (Fagus sylvatica L.) in an experimentally enhanced free air ozone setting

    Olbrich, Maren, E-mail: maren.olbrich@helmholtz-muenchen.d [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Gerstner, Elke; Bahnweg, Guenther [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Haeberle, Karl-Heinz; Matyssek, Rainer [Technische Universitaet Muenchen, Ecophysiology of Plants, Am Hochanger 13, 85354 Freising (Germany); Welzl, Gerhard [Institute of Developmental Genetics, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany); Heller, Werner; Ernst, Dieter [Institute of Biochemical Plant Pathology, Helmholtz Zentrum Muenchen - German Research Center for Environmental Health, 85764 Neuherberg (Germany)

    2010-04-15

    Tropospheric ozone causes severe oxidative stress in plants. To investigate the transcriptional responsiveness of adult trees to ozone, fully-expanded sun and shade leaves of mature beech trees were harvested at four time points over the entire vegetation period in 2005 and 2006. Microarray analyses were conducted on leaves from trees grown in the field under ambient and twice-ambient ozone concentrations at Kranzberger Forst (Bavaria). Beech trees changed their transcript levels in response to ozone. In the years 2005 and 2006 different transcription patterns were observed; this may have been a result of different weather conditions and ozone uptake. Furthermore, we obtained differences in mRNA expression patterns between shade and sun leaves. In the ozone-treated sun leaves of 2005, slightly up- and down-regulated transcript levels were detected, particularly in the spring and autumn, whereas shade leaves clearly exhibited reduced mRNA levels, particularly at the end of the vegetation period. In 2006, this pattern could not be confirmed, and in the autumn, four other transcripts were slightly up-regulated in ozone-treated shade leaves. In addition, two other transcripts were found to be influenced in sun leaves in the spring/summer. While we detected changes in the levels of only a few transcripts, the observed effects were not identical in both years. In conclusion, elevated ozone exhibited very small influence on the transcription levels of genes of mature beech trees. - At the transcriptional level, leaves of mature beech trees barely react to double ambient ozone concentrations; differences are detected primarily between sun/shade leaves and between different growing seasons.

  1. Transcriptional signatures in leaves of adult European beech trees (Fagus sylvatica L.) in an experimentally enhanced free air ozone setting

    Tropospheric ozone causes severe oxidative stress in plants. To investigate the transcriptional responsiveness of adult trees to ozone, fully-expanded sun and shade leaves of mature beech trees were harvested at four time points over the entire vegetation period in 2005 and 2006. Microarray analyses were conducted on leaves from trees grown in the field under ambient and twice-ambient ozone concentrations at Kranzberger Forst (Bavaria). Beech trees changed their transcript levels in response to ozone. In the years 2005 and 2006 different transcription patterns were observed; this may have been a result of different weather conditions and ozone uptake. Furthermore, we obtained differences in mRNA expression patterns between shade and sun leaves. In the ozone-treated sun leaves of 2005, slightly up- and down-regulated transcript levels were detected, particularly in the spring and autumn, whereas shade leaves clearly exhibited reduced mRNA levels, particularly at the end of the vegetation period. In 2006, this pattern could not be confirmed, and in the autumn, four other transcripts were slightly up-regulated in ozone-treated shade leaves. In addition, two other transcripts were found to be influenced in sun leaves in the spring/summer. While we detected changes in the levels of only a few transcripts, the observed effects were not identical in both years. In conclusion, elevated ozone exhibited very small influence on the transcription levels of genes of mature beech trees. - At the transcriptional level, leaves of mature beech trees barely react to double ambient ozone concentrations; differences are detected primarily between sun/shade leaves and between different growing seasons.

  2. Ambient oxygen promotes tumorigenesis.

    Ho Joong Sung

    Full Text Available Oxygen serves as an essential factor for oxidative stress, and it has been shown to be a mutagen in bacteria. While it is well established that ambient oxygen can also cause genomic instability in cultured mammalian cells, its effect on de novo tumorigenesis at the organismal level is unclear. Herein, by decreasing ambient oxygen exposure, we report a ∼50% increase in the median tumor-free survival time of p53-/- mice. In the thymus, reducing oxygen exposure decreased the levels of oxidative DNA damage and RAG recombinase, both of which are known to promote lymphomagenesis in p53-/- mice. Oxygen is further shown to be associated with genomic instability in two additional cancer models involving the APC tumor suppressor gene and chemical carcinogenesis. Together, these observations represent the first report directly testing the effect of ambient oxygen on de novo tumorigenesis and provide important physiologic evidence demonstrating its critical role in increasing genomic instability in vivo.

  3. The dynamics of ozone generation and mode transition in air surface micro-discharge plasma at atmospheric pressure

    We present the transient, dynamic behavior of ozone production in surface micro-discharge (SMD) plasma in ambient air. Ultraviolet absorption spectroscopy at 254 nm was used to measure the time development of ozone density in a confined volume. We observed that ozone density increases monotonically over 1000 ppm for at least a few minutes when the input power is lower than ∼0.1 W/cm2. Interestingly, when input power is higher than ∼0.1 W/cm2, ozone density starts to decrease in a few tens of seconds at a constant power density, showing a peak ozone density. A model calculation suggests that the ozone depletion at higher power density is caused by quenching reactions with nitrogen oxides that are in turn created by vibrationally excited nitrogen molecules reacting with O atoms. The observed mode transition is significantly different from classical ozone reactors in that the transition takes place over time at a constant power. In addition, we observed a positive correlation between time-averaged ozone density and the inactivation rate of Escherichia coli on adjacent agar plates, suggesting that ozone plays a key role in inactivating bacteria under the conditions considered here. (paper)

  4. Ozone-Induced Nasal Type 2 Immunity in Mice Is Dependent on Innate Lymphoid Cells.

    Kumagai, Kazuyoshi; Lewandowski, Ryan; Jackson-Humbles, Daven N; Li, Ning; Van Dyken, Steven J; Wagner, James G; Harkema, Jack R

    2016-06-01

    Epidemiological studies suggest that elevated ambient concentrations of ozone are associated with activation of eosinophils in the nasal airways of atopic and nonatopic children. Mice repeatedly exposed to ozone develop eosinophilic rhinitis and type 2 immune responses. In this study, we determined the role of innate lymphoid cells (ILCs) in the pathogenesis of ozone-induced eosinophilic rhinitis by using lymphoid-sufficient C57BL/6 mice, Rag2(-/-) mice that are devoid of T cells and B cells, and Rag2(-/-)Il2rg(-/-) mice that are depleted of all lymphoid cells including ILCs. The animals were exposed to 0 or 0.8 ppm ozone for 9 consecutive weekdays (4 h/d). Mice were killed 24 hours after exposure, and nasal tissues were selected for histopathology and gene expression analysis. ILC-sufficient C57BL/6 and Rag2(-/-) mice exposed to ozone developed marked eosinophilic rhinitis and epithelial remodeling (e.g., epithelial hyperplasia and mucous cell metaplasia). Chitinase-like proteins and alarmins (IL-33, IL-25, and thymic stromal lymphopoietin) were also increased morphometrically in the nasal epithelium of ozone-exposed C57BL/6 and Rag2(-/-) mice. Ozone exposure elicited increased expression of Il4, Il5, Il13, St2, eotaxin, MCP-2, Gob5, Arg1, Fizz1, and Ym2 mRNA in C57BL/6 and Rag2(-/-) mice. In contrast, ozone-exposed ILC-deficient Rag2(-/-)Il2rg(-/-) mice had no nasal lesions or overexpression of Th2- or ILC2-related transcripts. These results indicate that ozone-induced eosinophilic rhinitis, nasal epithelial remodeling, and type 2 immune activation are dependent on ILCs. To the best of our knowledge, this is the first study to demonstrate that ILCs play an important role in the nasal pathology induced by repeated ozone exposure. PMID:26559808

  5. Effects of Local Circulations, Turbulent Internal Boundary Layers, and Elevated Industrial Plumes on Coastal Ozone Pollution in the Downwind Kaohsiung Urban-Industrial Complex

    Yee-Lin Wu

    2010-01-01

    Full Text Available Linyuan (LY is a coastal station located down wind of the industrial city of Kaohsiung in southern Taiwan. This station is often affected by severe ozone pollution during sea breeze events. Intensive tethered ozone soundings were per formed at this station during a 4-day ozone episode in November, 2005. Back air trajectories were also calculated to track the origins of air masses arriving at the station during the experiment. The investigation revealed complicated ozone pro files in the lower at mo sphere (be low 1300 m both day and night. At night, industrial plumes forming no-ozone air layers were frequently distributed at 400 - 800 m. Mixing layers rapidly decreased from 800 - 1100 m down to 200 - 350 m in the late morning hours when sea breezes and thermal internal boundary layers (TIBLs developed. Recirculation of polluted in land air masses over the sea, the development of TIBLs, and the late development of sea-breeze events all are likely responsible for severe ozone pollution at the LY station. Elevated industrial plumes or ozone aloft above TIBLs revealed only aminor contribution to ozone pollution via a downward mixing process. Elevated ozone levels (140 - 170 ppb were of ten trapped within transitional layers of sea-breeze circulations at 600 - 800 m and were accompanied by ambient northerly flows parallel to the coast line, suggesting that an ozone pollution core likely formed over the west coast of Taiwan on ozone-episodic days when sea-breeze circulations developed.

  6. Mujer y medio ambiente

    Zuluaga Sánchez, Gloria Patricia

    1998-01-01

    El debate sobre mujer y medio ambiente es bastante nuevo y, por lo tanto, aun no hay consenso sobre como abordarlo, ni análisis muy profundos sobre la interacción de estas dos problemáticas tan complejas y que además atraviesan las demás temáticas. Con ello no se quiere negar el importante aporte que se ha hecho en tal sentido, por parte de colectividades y de algunas personas. Selene Herculano y Jacqueline Pitanguy (1993), mencionan que el medio ambiente no es una categoría específica y que ...

  7. Ambientes de aprendizaje computacionales

    Señas, Perla

    2001-01-01

    En el marco de las aplicaciones de la tecnología computacional a la educación se destaca de manera especial el trabajo sobre Ambientes de Aprendizaje. En él convergen tópicos relevantes de las Ciencias de la Computación y de la Educación. Se puede definir un Ambiente de Aprendizaje Computacional como un entorno integrado por un conjunto no homogéneo de elementos capaces de crear o recrear situaciones a partir de las cuales el alumno puede construir conocimiento y realizar aprendizajes y meta-...

  8. Removal of perfluorooctanoic acid and perfluorooctane sulfonate via ozonation under alkaline condition

    Lin, Angela Yu-Chen, E-mail: yuchenlin@ntu.edu.tw [Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan (China); Panchangam, Sri Chandana; Chang, Cheng-Yi [Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan (China); Hong, P.K. Andy [Department of Civil and Environmental Engineering, University of Utah, Salt Lake City, Utah 84112 (United States); Hsueh, Han-Fang [Graduate Institute of Environmental Engineering, National Taiwan University, 71, Chou-Shan Rd., Taipei 106, Taiwan (China)

    2012-12-15

    Highlights: Black-Right-Pointing-Pointer PFOA and PFOS are degraded by O{sub 3} or O{sub 3}/H{sub 2}O{sub 2} treatment at pH 11. Black-Right-Pointing-Pointer Degradation of PFOA and PFOS by O{sub 3} or O{sub 3}/H{sub 2}O{sub 2} under alkaline condition is enhanced when the compounds are pretreated by 15 min of ozonation at ambient pH (4-5). Black-Right-Pointing-Pointer PFOA and PFOS removal by O{sub 3} or O{sub 3}/H{sub 2}O{sub 2} at pH 11 was efficient relative to existing methods in terms of energy and contact time. - Abstract: The elimination of recalcitrant, ubiquitous perfluoroalkyl acids (PFAAs) such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) is desirable for reducing potential human health and environmental risks. We here report the degradation of PFOA and PFOS by 85-100% via ozonation under alkaline condition being studied at environmentally relevant contaminant concentrations of 50 {mu}g L{sup -1} to 5 mg L{sup -1}, with enhanced removal rates by addition of hydrogen peroxide. Enhanced removal is achieved by ozonation pretreatment for 15 min at the ambient pH (i.e. 4-5), followed by elevation of pH to 11 and continued ozonation treatment for 4 h. The ozonation pretreatment resulted in increased degradation of PFOA by 56% and PFOS by 42%. The results indicated hydroxyl radical-driven degradation of PFOA and PFOS in both treatments by ozone and peroxone under alkaline conditions. Wastewaters from electronics and semiconductor fabrication plants in the Science Park of Hsinchu city, Taiwan containing PFOA and PFOS have been readily treated by ozonation under alkaline condition. Treatment of PFAAs by ozone or peroxone proves to be efficient in terms of energy requirement, contact time, and removal rate.

  9. Removal of perfluorooctanoic acid and perfluorooctane sulfonate via ozonation under alkaline condition

    Highlights: ► PFOA and PFOS are degraded by O3 or O3/H2O2 treatment at pH 11. ► Degradation of PFOA and PFOS by O3 or O3/H2O2 under alkaline condition is enhanced when the compounds are pretreated by 15 min of ozonation at ambient pH (4–5). ► PFOA and PFOS removal by O3 or O3/H2O2 at pH 11 was efficient relative to existing methods in terms of energy and contact time. - Abstract: The elimination of recalcitrant, ubiquitous perfluoroalkyl acids (PFAAs) such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) is desirable for reducing potential human health and environmental risks. We here report the degradation of PFOA and PFOS by 85–100% via ozonation under alkaline condition being studied at environmentally relevant contaminant concentrations of 50 μg L−1 to 5 mg L−1, with enhanced removal rates by addition of hydrogen peroxide. Enhanced removal is achieved by ozonation pretreatment for 15 min at the ambient pH (i.e. 4–5), followed by elevation of pH to 11 and continued ozonation treatment for 4 h. The ozonation pretreatment resulted in increased degradation of PFOA by 56% and PFOS by 42%. The results indicated hydroxyl radical-driven degradation of PFOA and PFOS in both treatments by ozone and peroxone under alkaline conditions. Wastewaters from electronics and semiconductor fabrication plants in the Science Park of Hsinchu city, Taiwan containing PFOA and PFOS have been readily treated by ozonation under alkaline condition. Treatment of PFAAs by ozone or peroxone proves to be efficient in terms of energy requirement, contact time, and removal rate.

  10. Ozone-Induced Type 2 Immunity in Nasal Airways. Development and Lymphoid Cell Dependence in Mice.

    Ong, Chee Bing; Kumagai, Kazuyoshi; Brooks, Phillip T; Brandenberger, Christina; Lewandowski, Ryan P; Jackson-Humbles, Daven N; Nault, Rance; Zacharewski, Timothy R; Wagner, James G; Harkema, Jack R

    2016-03-01

    Inhalation exposures to ozone commonly encountered in photochemical smog cause airway injury and inflammation. Elevated ambient ozone concentrations have been epidemiologically associated with nasal airway activation of neutrophils and eosinophils. In the present study, we elucidated the temporal onset and lymphoid cell dependency of eosinophilic rhinitis and associated epithelial changes in mice repeatedly exposed to ozone. Lymphoid cell-sufficient C57BL/6 mice were exposed to 0 or 0.5 parts per million (ppm) ozone for 1, 2, 4, or 9 consecutive weekdays (4 h/d). Lymphoid cell-deficient, Rag2(-/-)Il2rg(-/-) mice were similarly exposed for 9 weekdays. Nasal tissues were taken at 2 or 24 hours after exposure for morphometric and gene expression analyses. C57BL/6 mice exposed to ozone for 1 day had acute neutrophilic rhinitis, with airway epithelial necrosis and overexpression of mucosal Ccl2 (MCP-1), Ccl11 (eotaxin), Cxcl1 (KC), Cxcl2 (MIP-2), Hmox1, Il1b, Il5, Il6, Il13, and Tnf mRNA. In contrast, 9-day ozone exposure elicited type 2 immune responses in C57BL/6 mice, with mucosal mRNA overexpression of Arg1, Ccl8 (MCP-2), Ccl11, Chil4 (Ym2), Clca1 (Gob5), Il5, Il10, and Il13; increased density of mucosal eosinophils; and nasal epithelial remodeling (e.g., hyperplasia/hypertrophy, mucous cell metaplasia, hyalinosis, and increased YM1/YM2 proteins). Rag2(-/-)Il2rg(-/-) mice exposed to ozone for 9 days, however, had no nasal pathology or overexpression of transcripts related to type 2 immunity. These results provide a plausible paradigm for the activation of eosinophilic inflammation and type 2 immunity found in the nasal airways of nonatopic individuals subjected to episodic exposures to high ambient ozone. PMID:26203683

  11. Suitability of Nicotiana tabacum 'Bel W3' for biomonitoring ozone in Sao Paulo, Brazil

    Nicotiana tabacum 'Bel W3' is a widely used sensitive bioindicator for ambient ozone, but it is rarely used in tropical countries. Our goal was to determine the suitability of this plant for biomonitoring ozone in the city of Sao Paulo by evaluating the relationships between leaf necroses and ozone under field conditions and measurements of chlorophyll a fluorescence and antioxidants in plants exposed to different concentrations of ozone in closed chambers. While a weak linear relationship between leaf injury and ozone concentrations (R2 = 0.10) was determined in the field, a strong linear relationship was observed in the chamber experiments. Maximum leaf injury was observed in plants submitted to 40 ppb, which coincided with a significant decrease in fluorescence and total ascorbic acid. The relationship between leaf damage observed in the field and ozone was improved when the concentrations were limited to 40 ppb (R2 = 0.28). - Nicotiana tabacum 'Bel W3' is suitable for indicating low ozone levels in Brazil

  12. The Influence of Photolysis Rate Constants in Ozone Production for the Paso del Norte Region

    Becerra, Fernando; Fitzgerald, Rosa

    2012-03-01

    In this research work we are focusing on understanding the relationship between photolysis rates and the photochemical ozone changes observed in the Paso del Norte region. The city of El Paso, Texas together with Ciudad Juarez, Mexico, forms the largest contiguous bi-national metropolitan area. This region suffers year-round ozone pollution events, and a better understanding is needed to mitigate them. Previous studies have found that ambient ozone concentrations tend to be higher on weekends rather than on weekdays, this phenomenon being referred to, as the ``weekend effect.'' If the ozone standard is exceeded more frequently on weekends, then this phenomenon must be considered in the design of ozone control strategies. In this work we investigate some of the most representative weekend ozone episodes at El Paso, TX, during the years 2009, 2010 and 2011 using the ozone photolysis rates. In this research the TUV radiative-transfer model is used to calculate the local photolysis rates and a UV MFRSR instrument is used to obtain experimental parameters. Seasonal variations and the weekday-weekend effect is studied. The results of this research will help to understand the underlying behavior of the photolysis rate constants when different atmospheric conditions are present.

  13. Ozone generation in positive and negative corona discharge fed by humid oxygen and carbon dioxide

    Skalny, J D; Orszagh, J; MatejcIk, S [Department of Experimental Physics, Comenius University, Mlynska dolina F-2, 84248 Bratislava (Slovakia); Mason, N J [Department of Physics and Astronomy, Open University, Walton Hall, Milton Keynes MK7 6AA (United Kingdom)], E-mail: skalny@fmph.uniba.sk

    2008-10-15

    The effect of humidity on ozone generation of positive and negative corona discharges fed by O{sub 2} and CO{sub 2} has been studied in the humidity range of 100-20 000 ppm. The experiments were carried out at an ambient temperature and pressure of 100 kPa. The increase in humidity of CO{sub 2} conspicuously suppressed the ozone generation in negative corona discharge at all values of the input energy densities into the discharge. The effect was less pronounced in oxygen. In contrast to decrease of ozone concentration observed in negative corona discharge, the presence of water both in O{sub 2} and CO{sub 2} acts catalytically. The ozone concentration has been found to increase remarkably (approximately 10 times) in oxygen, if the humidity was increased from 100 to 20 000 ppm. The dependence of ozone concentration on the gas humidity exhibited an extreme. The increase observed at humidity up to approximately 5000 ppm was followed by the marginal reduction in ozone concentration. Anyway, the values of this were considerably higher than those found in dry CO{sub 2}. The effect of humidity on ozone concentration will be discussed in relation to plasma chemical processes in studied discharges and their macroscopic parameters.

  14. Ozone generation in positive and negative corona discharge fed by humid oxygen and carbon dioxide

    The effect of humidity on ozone generation of positive and negative corona discharges fed by O2 and CO2 has been studied in the humidity range of 100-20 000 ppm. The experiments were carried out at an ambient temperature and pressure of 100 kPa. The increase in humidity of CO2 conspicuously suppressed the ozone generation in negative corona discharge at all values of the input energy densities into the discharge. The effect was less pronounced in oxygen. In contrast to decrease of ozone concentration observed in negative corona discharge, the presence of water both in O2 and CO2 acts catalytically. The ozone concentration has been found to increase remarkably (approximately 10 times) in oxygen, if the humidity was increased from 100 to 20 000 ppm. The dependence of ozone concentration on the gas humidity exhibited an extreme. The increase observed at humidity up to approximately 5000 ppm was followed by the marginal reduction in ozone concentration. Anyway, the values of this were considerably higher than those found in dry CO2. The effect of humidity on ozone concentration will be discussed in relation to plasma chemical processes in studied discharges and their macroscopic parameters.

  15. Influence of the ozone profile above Madrid (Spain) on Brewer estimation of ozone air mass factor

    M. Antón; López, M.; Costa, M. J.; Serrano, A; D. Bortoli; M. Bañón; Vilaplana, J. M.; A. M. Silva

    2009-01-01

    The methodology used by Brewer spectroradiometers to estimate the ozone column is based on differential absorption spectroscopy. This methodology employs the ozone air mass factor (AMF) to derive the total ozone column from the slant path ozone amount. For the calculating the ozone AMF, the Brewer algorithm assumes that the ozone layer is located at a fixed height of 22 km. However, for a real specific site the ozone presents a certain profile, which varies spatially and temporally depending ...

  16. Ozone-induced stomatal sluggishness develops progressively in Siebold's beech (Fagus crenata)

    We investigated the effects of ozone and leaf senescence on steady-state stomatal conductance and stomatal response to light variation. Measurements were carried out in a free-air ozone exposure experiment on a representative deciduous broadleaved tree species in Japan (Fagus crenata). Both steady-state and dynamic stomatal response to light variation varied intrinsically with season due to leaf senescence. Ozone induced the decrease in steady-state leaf gas exchange and the sluggish stomatal closure progressively. These findings suggest that ozone reduces the ability of plants to adapt to a fluctuating light environment under natural conditions, and therefore impairs plant growth and ability to control water loss. - Highlights: ► We investigated the effects of ozone and leaf senescence on stomatal response to light variation. ► Measurements were carried out in a free-air ozone exposure experiment on Siebold's beech. ► Stomatal response to light variation varied intrinsically with season due to leaf senescence. ► Steady-state stomatal conductance was reduced under elevated ozone. ► Ozone increased time for stomatal closing and reduced light-saturated photosynthesis progressively. - Ozone progressively induces a sluggishness of stomatal light response.

  17. Effect of Ozone Treatment on Inactivation of Escherichia coli and Listeria sp. on Spinach

    Shreya Wani

    2015-03-01

    Full Text Available The efficacy of “gaseous” ozone in reducing numbers and re-growth of food-borne pathogens, (Escherichia coli and Listeria spp., on leafy salads was investigated using spinach. A preliminary in vivo study showed 1-log reduction in six strains of E. coli and two species of Listeria spp. on spinach exposed to 1 ppm ozone for 10 min. A range of ozone treatments were explored to deliver optimal bacterial inactivation while maintaining the visual appearance (color of produce. Exposure to a higher ozone concentration for a shorter duration (10 ppm for 2 min significantly reduced E. coli and Listeria spp. viable counts by 1-log and the pathogens did not re-grow following treatment (over a nine-day storage period. Impacts of 1 and 10 ppm ozone treatments were not significantly different. Approximately 10% of the pathogen population was resistant to ozone treatment. We hypothesized that cell age may be one of several factors responsible for variation in ozone resistance. E. coli cells from older colonies demonstrated higher ozone resistance in subsequent experiments. Overall, we speculate that gaseous ozone treatment constitutes the basis for an alternative customer-friendly method to reduce food pathogen contamination of leafy produce and is worth exploring on a pilot-scale in an industrial setting.

  18. La radioactividad ambiental

    Rafael Núñez-Lagos Roglá

    2011-01-01

    Full Text Available Se explican los conceptos fundamentales relacionados con la radiactividad y se utilizan para describir la radiactividad ambiental. Se explican también los isótopos de largo periodo y las principales familias radioactivas junto con la radiación cósmica y los radionucleidos cosmogénicos.

  19. Ambient mass spectrometry imaging

    Janfelt, Christian; Nørgaard, Asger W

    2012-01-01

    Easy ambient sonic spray ionization (EASI) and desorption electrospray ionization (DESI) were used for imaging of a number of samples, including sections of rat brain and imprints of plant material on porous Teflon. A novel approach termed Displaced Dual-mode Imaging was utilized for the direct c...

  20. Phytotoxic and competitive effects of tall fescue on Ladino clover as modified by ozone and/or Rhizoctonia solani

    Kochhar, M.

    1974-01-01

    An effort was made to look at the effects of fescue and/or ozone on clover decline in the grass-clover mixture. The objectives of this study were to determine (1) if chemical interactions play a role in clover decline from a clover-fescue mixture, (2) if ozone affects the growth of clover, and (3) if ozone modifies plant-plant interactions between clover and fescue.

  1. Environmental auditing: An approach for characterizing tropospheric ozone risk to forests

    Hogsett, W.E.; Weber, J.E.; Tingey, D. [EPA, Corvallis, OR (United States); Herstrom, A.; Lee, E.H. [ManTech Inc., Corvallis, OR (United States); Laurence, J.A. [Boyce Thompson Institute for Plant Research, Ithaca, NY (United States)

    1997-01-01

    The risk tropospheric ozone poses to forests in the United States dependents on the variation in ozone exposure across the forests and the various environmental and climate factors predominant in the region. All these factors have a spatial nature; an approach to characterization of ozone risk is presented that places ozone exposure-response functions for species as seedlings and model-simulated tree and stand responses in a spatial context using a geographical information systems (GIS). The GIS is used to aggregate factors considered important in a risk characterization: (1) estimated ozone exposures over forested regions, (2) measures of ozone effects on species` and stand growth, and (3) spatially distributed environmental, genetic, and exposure influences on species` response to ozone. The GIS-based risk characterization provides an estimation the extent and magnitude of the potential ozone impact on forests. A preliminary risk characterization demonstrating this considered only the eastern United States and only the limited empirical data quantifying the effect of ozone exposures on forest tree species as seedlings. The area-weighted response of the annual seedling biomass loss formed the basis for a sensitivity ranking: sensitive-aspen and black cherry (14%-33% biomass loss over 50% of their distribution); moderately sensitive-tulip popular, loblolly pine, eastern white pine, and sugar maple (5%-13% biomass loss); insensitive-Virginia pine and red maple (0%-1% loss). Future GIS-based risk characterizations will include process-based model simulations of the three- to 5-year growth response of individual species as large trees. The interactive nature of GIS provides a tool to explore consequences of the range of climate conditions across a species` distribution, forest management practices, changing ozone precursors, regulatory control strategies, and other factors influencing the spatial distribution of ozone over time. 43 refs., 11 figs., 3 tabs.

  2. Emission sources contributing to tropospheric ozone over equatorial Africa during the summer monsoon

    I. Bouarar

    2011-05-01

    Full Text Available A global chemistry-climate model LMDz_INCA is used to investigate the contribution of African and Asian emissions to tropospheric ozone over central and West Africa during the summer monsoon. The model results show that ozone in this region is most sensitive to lightning NOx and to central African biomass burning emissions. However, other emission categories also contribute significantly to regional ozone. The maximum ozone changes due to lightning NOx occur in the upper troposphere between 400 hPa and 200 hPa over West Africa and downwind over the Atlantic Ocean. Biomass burning emissions mainly influence ozone in the lower and middle troposphere over central Africa, and downwind due to westward transport. Biogenic emissions of volatile organic compounds, which can be uplifted from the lower troposphere into higher altitudes by the deep convection that occurs over West Africa during the monsoon season, dominate the ozone changes in the upper troposphere and lower stratosphere region. Convective uplift of soil NOx emissions over the Sahel region also makes a significant contribution to ozone in the upper troposphere. Concerning African anthropogenic emissions, they make a lower contribution to ozone compared to the other emission categories. The model results indicate that most ozone changes due to African emissions occur downwind, especially over the Atlantic Ocean, far from the emission regions. The influence of Asian emissions should also be taken into account in studies of the ozone budget over Africa since they make a considerable contribution to ozone concentrations above 150 hPa. Using IPCC AR5 (Intergovernmental Panel on Climate Change; Fifth Assessment Report estimates of anthropogenic emissions for 2030 over Africa and Asia, the model calculations suggest largest changes in ozone due to the growth of emissions over Asia than over Africa over the next 20 years.

  3. Unequivocal detection of ozone recovery in the Antarctic Ozone Hole through significant increases in atmospheric layers with minimum ozone

    de Laat, Jos; van Weele, Michiel; van der A, Ronald

    2015-04-01

    An important new landmark in present day ozone research is presented through MLS satellite observations of significant ozone increases during the ozone hole season that are attributed unequivocally to declining ozone depleting substances. For many decades the Antarctic ozone hole has been the prime example of both the detrimental effects of human activities on our environment as well as how to construct effective and successful environmental policies. Nowadays atmospheric concentrations of ozone depleting substances are on the decline and first signs of recovery of stratospheric ozone and ozone in the Antarctic ozone hole have been observed. The claimed detection of significant recovery, however, is still subject of debate. In this talk we will discuss first current uncertainties in the assessment of ozone recovery in the Antarctic ozone hole by using multi-variate regression methods, and, secondly present an alternative approach to identify ozone hole recovery unequivocally. Even though multi-variate regression methods help to reduce uncertainties in estimates of ozone recovery, great care has to be taken in their application due to the existence of uncertainties and degrees of freedom in the choice of independent variables. We show that taking all uncertainties into account in the regressions the formal recovery of ozone in the Antarctic ozone hole cannot be established yet, though is likely before the end of the decade (before 2020). Rather than focusing on time and area averages of total ozone columns or ozone profiles, we argue that the time evolution of the probability distribution of vertically resolved ozone in the Antarctic ozone hole contains a better fingerprint for the detection of ozone recovery in the Antarctic ozone hole. The advantages of this method over more tradition methods of trend analyses based on spatio-temporal average ozone are discussed. The 10-year record of MLS satellite measurements of ozone in the Antarctic ozone hole shows a

  4. Experimental study of ozone synthesis

    A silent discharge ozonizer has been constructed with a design that enables the study of ozone concentration behaviour as a function of different parameters when oxygen used as a working gas. The behaviour of ozone concentration as a function of discharge current density has four characteristic regions. The concentration is enhanced by more than threefold whenever gas pressure is reduced by a factor of two. The flow rate of the working gas is a more effective parameter on ozone concentration than the gas pressure. When the flow rate is kept constant, and the pressure is decreased by 100%, the ozone concentration increases by only 10%. On the other hand, when the flow rate is decreased by 13%, the ozone concentration increases by 200%, whenever the gas pressure is kept constant. The concentration is nearly doubled when the gap space is increased by four times under the same conditions. The length of the discharge region, the thickness and the dielectric constant of the insulating materials are found to have a considerable effect on the generated ozone concentration. Also, the ozone concentration is ten times less when air is used instead of oxygen as a working gas. A maximum efficiency of 185 g/kWh, is obtained for the present system

  5. Ringrotbestrijding met behulp van ozon

    Wolf, van der J.M.; Bergervoet, J.H.W.; Kastelein, P.; Zouwen, van der P.S.

    2009-01-01

    Door het kistenreinigingsbedrijf van Frans Renne wordt een nieuwe kistenreinigingsmachine ontwikkeld. De methode is gebaseerd op ontsmetting met Ozon van recirculerend spoelwater en van kisten. In dit rapport wordt verslag gedaan van laboratorium-onderzoek naar het effect van ozon op ringrotbacterie

  6. IMPROVED TECHNIQUES FOR RESIDUAL OZONE

    Eight analytical methods for the determination of residual ozone in water are evaluated. Four are iodometric methods based on the reduction of ozone by iodide ion: the iodometric method, the amperometric method, the arsenic (III) back titration method, and the N, N-diethyl-p-phen...

  7. The effect of future ambient air pollution on human premature mortality to 2100 using output from the ACCMIP model ensemble

    Silva, Raquel A.; West, J. Jason; Lamarque, Jean-François; Shindell, Drew T.; Collins, William J.; Dalsoren, Stig; Faluvegi, Greg; Folberth, Gerd; Horowitz, Larry W.; Nagashima, Tatsuya; Naik, Vaishali; Rumbold, Steven T.; Sudo, Kengo; Takemura, Toshihiko; Bergmann, Daniel; Cameron-Smith, Philip; Cionni, Irene; Doherty, Ruth M.; Eyring, Veronika; Josse, Beatrice; MacKenzie, Ian A.; Plummer, David; Righi, Mattia; Stevenson, David S.; Strode, Sarah; Szopa, Sophie; Zengast, Guang

    2016-08-01

    Ambient air pollution from ground-level ozone and fine particulate matter (PM2.5) is associated with premature mortality. Future concentrations of these air pollutants will be driven by natural and anthropogenic emissions and by climate change. Using anthropogenic and biomass burning emissions projected in the four Representative Concentration Pathway scenarios (RCPs), the ACCMIP ensemble of chemistry-climate models simulated future concentrations of ozone and PM2.5 at selected decades between 2000 and 2100. We use output from the ACCMIP ensemble, together with projections of future population and baseline mortality rates, to quantify the human premature mortality impacts of future ambient air pollution. Future air-pollution-related premature mortality in 2030, 2050 and 2100 is estimated for each scenario and for each model using a health impact function based on changes in concentrations of ozone and PM2.5 relative to 2000 and projected future population and baseline mortality rates. Additionally, the global mortality burden of ozone and PM2.5 in 2000 and each future period is estimated relative to 1850 concentrations, using present-day and future population and baseline mortality rates. The change in future ozone concentrations relative to 2000 is associated with excess global premature mortality in some scenarios/periods, particularly in RCP8.5 in 2100 (316 thousand deaths year-1), likely driven by the large increase in methane emissions and by the net effect of climate change projected in this scenario, but it leads to considerable avoided premature mortality for the three other RCPs. However, the global mortality burden of ozone markedly increases from 382 000 (121 000 to 728 000) deaths year-1 in 2000 to between 1.09 and 2.36 million deaths year-1 in 2100, across RCPs, mostly due to the effect of increases in population and baseline mortality rates. PM2.5 concentrations decrease relative to 2000 in all scenarios, due to projected reductions in emissions, and

  8. Source attribution of tropospheric ozone

    Butler, T. M.

    2015-12-01

    Tropospheric ozone is a harmful pollutant with adverse effects on human health and ecosystems. As well as these effects, tropospheric ozone is also a powerful greenhouse gas, with an anthropogenic radiative forcing one quarter of that of CO2. Along with methane and atmospheric aerosol, tropospheric ozone belongs to the so-called Short Lived Climate forcing Pollutants, or SLCP. Recent work has shown that efforts to reduce concentrations of SLCP in the atmosphere have the potential to slow the rate of near-term climate change, while simultaneously improving public health and reducing crop losses. Unlike many other SLCP, tropospehric ozone is not directly emitted, but is instead influenced by two distinct sources: transport of air from the ozone-rich stratosphere; and photochemical production in the troposphere from the emitted precursors NOx (oxides of nitrogen), CO (Carbon Monoxide), and VOC (volatile organic compounds, including methane). Better understanding of the relationship between ozone production and the emissions of its precursors is essential for the development of targeted emission reduction strategies. Several modeling methods have been employed to relate the production of tropospheric ozone to emissions of its precursors; emissions perturbation, tagging, and adjoint sensitivity methods all deliver complementary information about modelled ozone production. Most studies using tagging methods have focused on attribution of tropospheric ozone production to emissions of NOx, even though perturbation methods have suggested that tropospheric ozone is also sensitive to VOC, particularly methane. In this study we describe the implementation into a global chemistry-climate model of a scheme for tagging emissions of NOx and VOC with an arbitrary number of labels, which are followed through the chemical reactions of tropospheric ozone production in order to perform attribution of tropospehric ozone to its emitted precursors. Attribution is performed to both

  9. Effects of ozone exposure on the xerophilic fungus, Eurotium amstelodami IS-SAB-01, isolated from naan bread.

    Antony-Babu, Sanjay; Singleton, Ian

    2011-01-01

    Xerophilic moulds cause contamination and spoilage of low moisture foods. This study examined the effect of ozone fumigation on growth of a Eurotium species isolated from naan bread. Two ozone treatments were used - a low-level long-term exposure (0.4 μmol/mol for 21 days) and high-level short-term exposure (300 μmol/mol for 5 to 120 min). For the low level exposure the combination of different media sucrose concentrations (0, 5, 10 and 20% w/v) with ozone treatment was also assessed. The growth of the isolate was found to be sensitive to low-level ozone fumigation depending on the media sucrose concentration and duration of the exposure. Low-level ozone exposure significantly (pasexual spores formed in media with no added sucrose, an effect not observed in media with higher sucrose levels. Electron microscope observations of colonies indicated that ozone exposed cultures produced lower numbers of cleistothecia. High-level ozone exposure for short durations reduced spore viability although 100% reduction in viability was achieved only after 120 min exposure. This work demonstrates that ozone may be used to reduce spore production in Eurotium but that the ozone effect can be mediated by sucrose levels in the growth medium. PMID:21093088

  10. Ozone's impact on public health: Contributions from indoor exposures to ozone and products of ozone-initiated chemistry

    Weschler, Charles J.

    2006-01-01

    OBJECTIVES: The associations between ozone concentrations measured outdoors and both morbidity and mortality may be partially due to indoor exposures to ozone and ozone-initiated oxidation products. In this article I examine the contributions of such indoor exposures to overall ozone-related health...

  11. Effects of 0.2 ppm ozone on biomarkers of inflammation in bronchoalveolar lavage fluid and bronchial mucosa of healthy subjects

    Krishna, M.T.; Madden, J.; Teran, L.M. [and others

    1998-08-01

    Short-term exposure to ozone at peak ambient levels induces neutrophil influx and impairs lung function in healthy humans. In order to investigate the mechanisms contributing to neutrophil recruitment and to examine the role of T-cells in the acute inflammatory response, we exposed 12 healthy humans to 0.2 parts per million (ppm) of ozone and filtered air on two separate occasions for 2 h with intermittent periods of rest and exercise (minute ventilation=30 L x min{sup -1}). Fibreoptic bronchoscopy was performed 6 h after the end of exposures. Total protein, tryptase, histamine, myeloperoxidase, interleukin (IL)-8 and growth-related oncogene-{alpha} (Gro-{alpha}) were measured and total and differential cell counts were performed in bronchoalveolar lavage (BAL) fluid. Flow cytometry was performed on BAL cells to study total T-cells, T-cell receptors ({alpha}{beta} and {gamma}{delta}), T-cell subsets (CD4+ and CD8+ cells) and activated T-cell subsets (CD25+). Using immunohistochemistry, neutrophils, mast cells, total T-cell numbers, T-cell subsets, CD25+ T-cells and leukocyte endothelial adhesion molecules including P-selectin, E-selectin, intercellular adhesion molecule (ICAM)-1 and vascular adhesion molecule (VCAM)-1 were quantified in the bronchial biopsies. Paired samples were available from nine subjects. Following ozone exposure there was a threefold increase in the proportion of polymorphonuclear neutrophils (PMNs) (p=0.07) and epithelial cells (p=0.05) in BAL fluid. This was accompanied by increased concentrations of IL-8 (p=0.01), Gro-{alpha} (p=0.05) and total protein (p=0.058). A significant positive correlation was demonstrated between the two chemokines and proportion of PMNs in BAL fluid. After ozone exposure there was a significant decrease in the CD4/CD8 ratio (p=0.05) and the proportion of activated CD4+ (p=001) and CD8+ T-cells (p=0.04). However, no significant changes were demonstrable in any of the inflammatory markers studied in the biopsies

  12. Evidências de interação genótipo x ambiente sobre características de crescimento em bovinos de corte Evidences of genotype x environment interaction for growth traits in beef cattle

    Maurício Mello de Alencar; Arthur dos Santos Mascioli; Alfredo Ribeiro de Freitas

    2005-01-01

    Objetivou-se, com este trabalho, estudar a interação genótipo x ambiente sobre os pesos à desmama (PD) e aos 12 meses de idade (P12), o ganho de peso diário da desmama aos 12 meses de idade (GDA) e o desempenho com base em um índice (CPG) de componentes principais envolvendo essas três características, em um rebanho da raça Canchim. O ambiente foi considerado a época de nascimento (primeiro e segundo semestres) do animal. Para avaliar a interação genótipo x ambiente, foram utilizadas duas met...

  13. Options to accelerate ozone recovery: ozone and climate benefits

    J. S. Daniel

    2010-08-01

    Full Text Available Hypothetical reductions in future emissions of ozone-depleting substances (ODSs and N2O are evaluated in terms of effects on equivalent effective stratospheric chlorine (EESC, globally-averaged total column ozone, and radiative forcing through 2100. Due to the established success of the Montreal Protocol, these actions can have only a fraction of the impact on ozone depletion that regulations already in force have had. If all anthropogenic ODS and N2O emissions were halted beginning in 2011, ozone is calculated to be higher by about 1–2% during the period 2030–2100 compared to a case of no additional restrictions. Direct radiative forcing by 2100 would be about 0.23 W/m2 lower from the elimination of anthropogenic N2O emissions and about 0.005 W/m2 lower from the destruction of the chlorofluorocarbon (CFC bank. Due to the potential impact of N2O on future ozone levels, we provide an approach to incorporate it into the EESC formulation, which is used extensively in ozone depletion analyses. The ability of EESC to describe total ozone changes arising from additional ODS and N2O controls is also quantified.

  14. Ambient Air Quality Data Inventory

    U.S. Environmental Protection Agency — The Office of Air and Radiation??s (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as...

  15. Ambient Air Quality Data Inventory

    U.S. Environmental Protection Agency — The Office of Air and Radiation's (OAR) Ambient Air Quality Data (Current) contains ambient air pollution data collected by EPA, other federal agencies, as well as...

  16. Monitoring of Ambient Air Quality in India - A Review

    Devendra Dohare; Vijayant Panday

    2014-01-01

    Air pollution is a serious problem all over the world which causes terrific loss to human health and other living being. Sulphur Dioxide(SO2),Nitrogen Dioxide(NO2),Particulate Matter (PM2.5, PM10), Ozone(O3), Lead (Pb), Carbon Monoxide(CO), Benzene(C6H6) and Nickel(Ni) are some of the parameters which have significant impact on environmental pollution. Purpose of this paper is to review the literature relating to the monitoring of ambient air pollution in India and compare the sam...

  17. Assessment of ozone effects on nitrate export from Hubbard Brook Watershed 6

    The impact of the air pollution ozone on soil N dynamics and temporal and spatial patterns of streamflow nitrate flux at the Hubbard Brook Experimental Forest Watershed 6 during the 1964-1994 period was assessed using aggregated (one-cell) and spatially explicit (208-cell) versions of the SImple NItrogen Cycle (SINIC) model. Simulated ozone effects included reductions in stomatal conductance and plant N demand. Model uncertainty was evaluated using Monte Carlo simulations. Ambient ozone was estimated to cause an additional 0.042 gN/m2 per year of nitrate export, 12% of the mean annual streamflow nitrate flux. The 95% credible interval of this estimate was 0.002-0.083 gN/m2 per year, or 0.72-27.3% of the annual flux. The large uncertainty in this estimate suggests that it may be difficult to identify ozone effects on nitrate export utilizing long term data from a single site. - Ambient ozone was estimated to cause an additional 0.042 gN/m2 per year of nitrate to be exported from Hubbard Brook Watershed 6 during 1964-1994

  18. The effect of winter stress on Ilex aquifolium L.previously fumigated with ozone

    Ranford, Jonathan [Applied Sciences, Staffordshire University, College Road, Stoke-on-Trent, Staffordshire, ST4 2DE (United Kingdom)]. E-mail: jon.ranford@staffs.ac.uk; Reiling, Kevin [Applied Sciences, Staffordshire University, College Road, Stoke-on-Trent, Staffordshire, ST4 2DE (United Kingdom)

    2007-01-15

    European Holly (Ilex aquifolium) received either charcoal-filtered air (CFA) or CFA with 70 nl l{sup -1} ozone added for 7 h day{sup -1} over a 28 day period. Plants were then transferred into cooling incubators for hardening (4 {sup o}C day/2 {sup o}C night; day length 12 h) for 7 days and then to the frosting stage (2 {sup o}C day and -5, -10 or -15 {sup o}C night) for 4 days. The plants were then placed in ambient conditions. Treatment produced significant differences in chlorophyll fluorescence data. Stomatal conductance was significantly higher for the ozone treatments though both showed a general decline over all temperature regimes. Ozone also significantly increased electrolyte leakage and reduced winter survival. These results show that ambient concentrations of ozone can reduce the tolerance of I. aquifolium to freezing stress, which may have serious implications for its establishment and survival. - Exposure to ozone decreases the winter hardening capability and markedly increases the frost sensitivity of Ilex aquifolium.

  19. Is the Ozone Hole over Your Classroom?

    Cordero, Eugene C.

    2002-01-01

    Reports on a survey of first year university science students regarding their understanding of the ozone layer, ozone depletion, and the effect of ozone depletion on Australia. Suggests that better teaching resources for environmental issues such as ozone depletion and global warming are needed before improvements in student understanding can be…

  20. Generation of ozonized water by surface discharge

    In order to generate ozonized water, both ozonizer and reaction tub have generally been used. In this study water is introduced to the discharge space produced by surface discharge. Two devices of the ozonizer and reactional vessel were unified. As a result, dissolved ozone concentration of 0.7 ppm was obtained on 3.5 watts discharge power. (author)

  1. NIF Ambient Vibration Measurements

    LLNL has an ongoing research and development project that includes developing data acquisition systems with remote wireless communication for monitoring the vibrations of large civil engineering structures. In order to establish the capability of performing remote sensing over an extended period of time, the researchers needed to apply this technology to a real structure. The construction of the National Ignition Facility provided an opportunity to test the data acquisition system on a large structure to monitor whether the facility is remaining within the strict ambient vibration guidelines. This document will briefly discuss the NIF ambient vibration requirements and summarize the vibration measurements performed during the Spring and Summer of 1999. In addition, a brief description of the sensors and the data acquisition systems will be provided in Appendix B

  2. DMAH ozone measurement net

    D. Pagès

    2006-01-01

    Full Text Available The complexity of the study of tropospheric ozone lies in the fact that it is a secondary pollutant. It is not emitted by a source, instead its concentration in the air depends on other compounds (especially the nitrogen oxides emitted by motor vehicles and the volatile organic compounds emitted by the industry and the vegetation and meteorological factors (especially solar radiation and temperature. The European legislation compells to make measurements of the tropospheric ozone due to its effects on people (fatigue, irritation of the mucous membranes, aggravation of asthma ... and on environment (decrease of the production of cereals, synergy with plagues .... The measuring net in Catalonia belongs to the Department of Environment and Housing (DMAH. It has a pyramidal structure and it allows a surveillance to notify in case of exceeding a certain threshold. From the registered data of last years it is shown that the number of incidences is related to meteorology. They are more frequent during afternoon and the behaviour of this pollutant is different according to the proximity of the point of measurement to the sources of its precursors.

  3. Formation and emissions of carbonyls during and following gas-phase ozonation of indoor materials

    Poppendieck, D. G.; Hubbard, H. F.; Weschler, C. J.; Corsi, R. L.

    Ozone concentrations that are several orders of magnitude greater than typical urban ambient concentrations are necessary for gas-phase ozonation of buildings, either for deodorization or for disinfection of biological agents. However, there is currently no published literature on the interaction of building materials and ozone under such extreme conditions. It would be useful to understand, for example in the case of building re-occupation planning, what types and amounts of reaction products may form and persist in a building after ozonation. In this study, 24 materials were exposed to ozone at concentrations of 1000 ppm in the inlet stream of experimental chambers. Fifteen target carbonyls were selected and measured as building ozonation by-products (BOBPs). During the 36 h that include the 16 h ozonation and 20 h persistence phase, the total BOBP mass released from flooring and wall coverings ranged from 1 to 20 mg m -2, with most of the carbonyls being of lower molecular weight (C 1-C 4). In contrast, total BOBP mass released from wood-based products ranged from 20 to 100 mg m -2, with a greater fraction of the BOBPs being heavier carbonyls (C 5-C 9). The total BOBP mass released during an ozonation event is a function of both the total surface area of the material and the BOBP emission rate per unit area of material. Ceiling tile, carpet, office partition, and gypsum wallboard with flat latex paint often have large surface areas in commercial buildings and these same materials exhibited relatively high BOBP releases. The greatest overall BOBP mass releases were observed for three materials that building occupants might have significant contact with: paper, office partition, and medium density fiberboard, e.g., often used in office furniture. These materials also exhibited extended BOBP persistence following ozonation; some BOBPs (e.g., nonanal) persist for months or more at emission rates large enough to result in indoor concentrations that exceed their odor

  4. Formation of environmentally persistent free radicals from the heterogeneous reaction of ozone and polycyclic aromatic compounds.

    Borrowman, Cuyler K; Zhou, Shouming; Burrow, Timothy E; Abbatt, Jonathan P D

    2016-01-01

    In the 1980s long-lived radical species were identified in cigarette tar. Since then, environmentally persistent free radicals (EPFRs) have been observed in ambient particulate matter, and have been generated in particulate matter generated from internal combustion engines. For the first time, we measure in situ the formation and decay of EPFRs through the heterogeneous reaction of ozone and several polycyclic aromatic compounds (PAC). Solid anthracene (ANT), pyrene (PY), benzo[a]pyrene (BAP), benzo[ghi]perylene (BGHIP), 1,4-naphthoquinone (1,4NQ), and 9,10-anthraquinone (AQ) were reacted with gas-phase ozone in a flow system placed in the active cavity of an electron paramagnetic resonance (EPR) spectrometer, and the formation of radicals was measured on the timescale of tens of minutes at ambient levels of ozone down to 30 ppb. For most substrates the net radical production is initially rapid, slows at intermediate times, and is followed by a slow decay. For oxidized solid BAP, radical signal persists for many days in the absence of ozone. To evaluate the effect of substrate phase, the solid PAHs were also dissolved in squalane, an organic oil inert to ozone, which yielded a much higher maximum radical concentration and faster radical decay when exposed to ozone. With higher mobility, reactants were apparently able to more easily diffuse and react with each other, yielding the higher radical concentrations. The EPR spectra exhibit three radicals types, two of which have been assigned to semiquinone species and one to a PAH-derived, carbon-centered radical. Although our system uses levels of PAC not typically found in the environment it is worth noting that the amounts of radical formed, on the order of 10(18) radicals per g, are comparable to those observed in ambient particulate matter. PMID:26603953

  5. Ozonated olive oils and the troubles

    Bulent Uysal

    2014-01-01

    One of the commonly used methods for ozone therapy is ozonated oils. Most prominent type of used oils is extra virgin olive oil. But still, each type of unsaturated oils may be used for ozonation. There are a lot of wrong knowledge on the internet about ozonated oils and its use as well. Just like other ozone therapy studies, also the studies about ozone oils are inadequate to avoid incorrect knowledge. Current data about ozone oil and its benefits are produced by supplier who oversees financ...

  6. Ozone fluxes over South-East Asian tropical rainforest and oil palm plantation

    Muller, Jennifer; Coyle, Mhairi; Helfter, Carole; Dorsey, James; Gallagher, Martin; Percival, Carl; Nemitz, Eiko; Fowler, David

    2010-05-01

    Ozone flux measurements were made over a South-East Asian tropical rainforest (April & June/July 2008) and an oil palm plantation (June 2008), as part of the NERC OP3 and ACES projects. Flux measurements over the rainforest were made at the Bukit Atur Global Atmospheric Watch (GAW) tower, where ozone fluxes were measured by the gradient approach (concentrations at 30, 45, 60, 75 m) and by eddy-covariance (45 and 75 m). The hourly median flux at the forest site peaked before midday and did not differ greatly between Period 1 (P1, April, end of wet season) and Period 3 (P3, June/July, dry season). The periods were however clearly contrasted by the different levels of ambient ozone and concentrations were larger during P1 by about 50 %, with diurnal hourly medians ranging from 26 - 38 ?g m-3 in P1 versus 15 - 27 ?g m-3 in P3. Ozone deposition velocities were smaller during P1 than P3 and median daytime maxima of deposition velocity in P1 were 5 mm s-1 compared to 11 mm s-1 in P3. The magnitude of fluxes and deposition velocities are similar to those observed over the Amazon rainforest (Rummel et al., 2007), but the diurnal profile differs slightly as ozone concentrations showed a stronger diurnal amplitude in the Amazon. Fluxes from 45 and 75 m are compared and ozone flux divergence with height is investigated. Flux measurements at the oil palm plantation were made using the eddy covariance method for 8 days (4th to 11th June 2008). During this period concentrations were very small with a diurnal range of 0 - 7 ?g m-3, probably due to the combined effect of a low measurement height, low turbulence and O3 destruction by soil NO emissions. However, median deposition velocity was 5 mm s-1 indicating that the oil palms are an effective sink for ozone. The ozone flux will be decomposed into stomatal ozone uptake by the vegetation, estimated from conductance modelling, ozone destruction by VOC chemistry (estimated from the measured VOC concentrations) and ozone destruction

  7. Modelling future changes in surface ozone: a parameterized approach

    O. Wild

    2011-10-01

    Full Text Available This study describes a simple parameterization to estimate regionally averaged changes in surface ozone due to past or future changes in anthropogenic precursor emissions based on results from 14 global chemistry transport models. The method successfully reproduces the results of full simulations with these models. For a given emission scenario it provides the ensemble mean surface ozone change, a regional source attribution for each change, and an estimate of the associated uncertainty represented by the variation between models. Using the Representative Concentration Pathway (RCP emission scenarios as an example, we show how regional surface ozone is likely to respond to emission changes by 2050 and how changes in precursor emissions and atmospheric methane contribute to this. Surface ozone changes are substantially smaller than expected with the SRES A1B, A2 and B2 scenarios, reflecting the assumptions of more stringent precursor emission controls under the RCP scenarios. We find an average difference of around 5 ppb between the outlying RCP 2.6 and RCP 8.5 scenarios, about 75% of which can be attributed to differences in methane abundance. The study reveals the increasing importance of limiting atmospheric methane growth as emissions of other precursors are controlled, but highlights differences in modelled ozone responses to methane changes of as much as a factor of two, indicating that this remains a major uncertainty in current models.

  8. Short-term Climate Change, Recent Economic Slowdown and Surface Ozone in the US for the Past Decades

    Chu, S.; Evangelista, M.

    2012-12-01

    Stagnant high pressure systems in the warm season have long been known to be conducive to high surface ozone concentrations. Variation in the strength and duration of these high pressure systems also provides a good indicator for short-term climate changes. In this study, we have developed a stagnant high pressure index (SH) to examine whether significant changes in ozone conducive conditions in the past 3 decades have actually been observed. We compared the trend of SH index with annual ozone design values in 45 major metropolitan areas nationwide to see what impact it had on efforts to control surface ozone for the past three decades. Our results show a significant increase in SH index in the past decade - a clear indication of current climate change to a more ozone conducive atmosphere. We also found that the accelerated decline in ambient ozone trend from 2007 to 2010 could not be explained by meteorology and existing emission controls except by essentially the recent economic slowdowns. However, the encouraging fact is that even with the rapid increase of stagnant high pressure systems in the past decade, ozone control strategies still managed to keep a steady improvement in ozone air quality in the U.S.

  9. Ambient air pollution and pregnancy-induced hypertensive disorders

    Pedersen, Marie; Stayner, Leslie; Slama, Rémy;

    2014-01-01

    .5), carbon monoxide (CO), ozone (O3), proximity to major roads, and traffic density met our inclusion criteria. Most studies reported that air pollution increased risk for pregnancy-induced hypertensive disorders. There was significant heterogeneity in meta-analysis, which included 16 studies reporting on...... ambient air pollution and pregnancy-induced hypertensive disorders including gestational hypertension and preeclampsia. We searched electronic databases for English language studies reporting associations between ambient air pollution and pregnancy-induced hypertensive disorders published between December......-analysis combined odds ratio associated with a 5-μg/m3 increase in PM2.5 was 1.57 (95% confidence interval, 1.26-1.96) for combined pregnancy-induced hypertensive disorders and 1.31 (95%confidence interval, 1.14-1.50) for preeclampsia [corrected]. Our results suggest that exposure to air pollution increases the...

  10. Anodic Materials for Electrocatalytic Ozone Generation

    Yun-Hai Wang; Qing-Yun Chen

    2013-01-01

    Ozone has wide applications in various fields. Electrocatalytic ozone generation technology as an alternative method to produce ozone is attractive. Anodic materials have significant effect on the ozone generation efficiency. The research progress on anodic materials for electrocatalytic ozone generation including the cell configuration and mechanism is addressed in this review. The lead dioxide and nickel-antimony-doped tin dioxide anode materials are introduced in detail, including their st...

  11. Effect of an ozone-generating air-purifying device on reducing concentrations of formaldehyde in air

    Esswein, E.J. [Univ. of Utah School of Medicine, Salt Lake City, UT (United States); Boeniger, M.F. [National Institute for Occupational Safety, Cincinnati, OH (United States)

    1994-02-01

    Formaldehyde, an air contaminant found in many indoor air investigations, poses distinct occupational exposure hazards in certain job categories (e.g., mortuary science) but is also of concern when found or suspected in office buildings and homes. A variety of air-purifying devices (APDs) are currently available or marketed for application to reduce or remove concentrations of a variety of indoor air pollutants through the use of ozone as a chemical oxidant. An investigation was conducted to determine if concentrations of formaldehyde similar to those found in industrial hygiene evaluations of funeral homes could be reduced with the use of an ozone-generating APD. An ozone-generating APD was placed in an exposure chamber and formaldehyde-containing embalming solution was allowed to evaporate naturally, creating peak and mean chamber concentrations of 2.5 and 1.3 ppm, respectively. Continuous-reading instruments were used to sample for formaldehyde and ozone. Active sampling methods were also used to sample simultaneously for formaldehyde and a possible reactant product, formic acid. Triplicate measurements were made in each of three evaluations: formaldehyde alone, ozone alone, and formaldehyde and ozone combined. Concentrations of formaldehyde were virtually identical with and without 0.5 ppm ozone. No reduction in formaldehyde concentration was found during a 90-minute evaluation using ozone at this concentration with peak and average concentrations of approximately 2.5 and 1.3 ppm formaldehyde, respectively. The results of this investigation suggest that the use of ozone is ineffective in reducing concentrations of formaldehyde. Because ozone has demonstrated health hazards, and is a regulated air contaminant in both the occupational and ambient environment, the use of ozone as an air purification agent in indoor air does not seem warranted. 25 refs., 5 figs., 4 tabs.

  12. Salud ambiental: conceptos y actividades

    Ordóñez Gonzalo A.

    2000-01-01

    La finalidad del trabajo es aportar información y propuestas conceptuales que faciliten la tarea de quienes tienen a su cargo la sistematización institucional de la salud ambiental. Se hace un análisis de la noción de "ambiente" para la cual se sugiere una definición, y se examina el lugar de la salud ambiental en el contexto de los problemas ambientales y sus vertientes "verde" y "azul". Se examinan denominaciones equivalentes de salud ambiental y se introducen los servicios de salud ambient...

  13. Ozone Applications in Food Industry

    Elif Savaş

    2014-03-01

    Full Text Available Known as active oxygen Ozone (O3, are among the most effective antimicrobials. The sun's ultraviolet rays and ozone caused by electric arcs of lightning occurring instantly around the world, and is available as a protective shield protects the animals against the effects of the sun's radiation. In the food industry, directly or indirectly in contact with food during processing of foods and chemical treatment of water disinfection bacteriological emerges as an alternative protection method. In this study, the effects of the ozone applications will evaluated as an alternative to conventional disinfectants in food industry.

  14. Ozone and Ozonated Oils in Skin Diseases: A Review

    Travagli, V.; Zanardi, I.; Valacchi, G.; Bocci, V.

    2010-01-01

    Although orthodox medicine has provided a variety of topical anti-infective agents, some of them have become scarcely effective owing to antibiotic- and chemotherapeutic-resistant pathogens. For more than a century, ozone has been known to be an excellent disinfectant that nevertheless had to be used with caution for its oxidizing properties. Only during the last decade it has been learned how to tame its great reactivity by precisely dosing its concentration and permanently incorporating the gas into triglycerides where gaseous ozone chemically reacts with unsaturated substrates leading to therapeutically active ozonated derivatives. Today the stability and efficacy of the ozonated oils have been already demonstrated, but owing to a plethora of commercial products, the present paper aims to analyze these derivatives suggesting the strategy to obtain products with the best characteristics. PMID:20671923

  15. Seasonal and diurnal gas exchange differences in ozone-sensitive common milkweed (Asclepias syriaca L.) in relation to ozone uptake

    Bergweiler, Chris [Department of Plant, Soil, and Insect Sciences, University of Massachusetts, Amherst, MA 01003 (United States)], E-mail: bergweiler@nre.umass.edu; Manning, William J. [Department of Plant, Soil, and Insect Sciences, University of Massachusetts, Amherst, MA 01003 (United States); Chevone, Boris I. [Department of Plant Pathology, Physiology, and Weed Science, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States)

    2008-03-15

    Stomatal conductance and net photosynthesis of common milkweed (Asclepias syriaca L.) plants in two different soil moisture regimes were directly quantified and subsequently modeled over an entire growing season. Direct measurements captured the dynamic response of stomatal conductance to changing environmental conditions throughout the day, as well as declining gas exchange and carbon assimilation throughout the growth period beyond an early summer maximum. This phenomenon was observed in plants grown both with and without supplemental soil moisture, the latter of which should theoretically mitigate against harmful physiological effects caused by exposure to ozone. Seasonally declining rates of stomatal conductance were found to be substantial and incorporated into models, making them less susceptible to the overestimations of effective exposure that are an inherent source of error in ozone exposure indices. The species-specific evidence presented here supports the integration of dynamic physiological processes into flux-based modeling approaches for the prediction of ozone injury in vegetation. - Temporal variation in physiological processes underlying diurnal and seasonal ozone uptake are described for a key ozone bioindicator species of North America.

  16. Seasonal and diurnal gas exchange differences in ozone-sensitive common milkweed (Asclepias syriaca L.) in relation to ozone uptake

    Stomatal conductance and net photosynthesis of common milkweed (Asclepias syriaca L.) plants in two different soil moisture regimes were directly quantified and subsequently modeled over an entire growing season. Direct measurements captured the dynamic response of stomatal conductance to changing environmental conditions throughout the day, as well as declining gas exchange and carbon assimilation throughout the growth period beyond an early summer maximum. This phenomenon was observed in plants grown both with and without supplemental soil moisture, the latter of which should theoretically mitigate against harmful physiological effects caused by exposure to ozone. Seasonally declining rates of stomatal conductance were found to be substantial and incorporated into models, making them less susceptible to the overestimations of effective exposure that are an inherent source of error in ozone exposure indices. The species-specific evidence presented here supports the integration of dynamic physiological processes into flux-based modeling approaches for the prediction of ozone injury in vegetation. - Temporal variation in physiological processes underlying diurnal and seasonal ozone uptake are described for a key ozone bioindicator species of North America

  17. Yield and nutritive quality of sericea lespedeza (Lespedeza cuneata) and little bluestem (Schizachyrium scoparium) exposed to ground-level ozone

    Powell, M.C.; Muntifering, R.B.; Lin, J.C.; Chappelka, A.H

    2003-04-01

    Ground-level ozone decreased the nutritive quality of select warm-season forages for ruminant herbivores. - Sericea lespedeza (Lespedeza cuneata cv. Interstate 76) and little bluestem (Schizachyrium scoparium cv. Aldous) were raised from seed in a glasshouse, transplanted into 5.7-l pots and placed into open-top chambers (OTC) on 6 June 1999. Following a 7-day adjustment period, each of six OTCs (duplicate OTCs per treatment) was ventilated with either air that had been carbon-filtered (CF) to remove ambient ozone (O{sub 3}); non-filtered (NF), representative of ambient air; or enriched to twice-ambient O{sub 3} concentration (2X). Primary-growth forage was harvested on days 7, 32, 46, 59 and 72 following the start of fumigation, and regrowth forage from the first primary-growth harvest was harvested on days 36, 54 and 72 following the start of fumigation. Dry matter (DM) yield of either forage species did not differ among treatments except in the final regrowth period when yield of sericea lespedeza was greater for the NF than 2X O{sub 3} treatment. In vitro DM digestibility (IVDMD) and concentrations of crude protein (CP), soluble phenolics (SP) and condensed tannins (CT) in primary-growth sericea lespedeza did not differ between treatments, but NF primary-growth forage had higher concentration of protein-precipitating tannins (PPT) than did 2X primary-growth forage. Concentrations of neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) were higher in NF and 2X than in CF primary-growth sericea lespedeza. Similarly, concentrations of NDF and ADL were higher, and IVDMD was lower for NF and 2X than for CF regrowth sericea lespedeza. Concentrations of ADF and ADL were lower, whereas IVDMD, in vitro NDF digestibility (IVNDFD) and concentrations of CP and SP were greater, in CF than in NF and 2X primary-growth little bluestem. Percentages IVDMD and IVNDFD and concentrations of CP and SP in NF primary-growth little bluestem were

  18. Atmospheric blocking signatures in total ozone and ozone miniholes

    Barriopedro Cepero, David; Antón Martínez, Manuel; García García, José Agustín

    2010-01-01

    This paper analyzes the statistical relationship between the total ozone column (TOC) and atmospheric blocking using 40-yr European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-40) data for the 1978-98 period, with special emphasis on winter and the European and eastern Pacific sectors. Regional blocking occurrence is accompanied by a decrease of TOC within the anticyclonic circulation region and a distinctive ozone increase upstream and downstream (upstream and south) i...

  19. The effects of tropospheric ozone on the species dynamics of calcareous grassland

    Although ozone has been shown to reduce the growth of individual species and to alter the composition of simple species mixtures, there is little understanding of its long-term effects on species dynamics and composition in real communities. Intact turfs of calcareous grassland were exposed to four different ozone regimes in open-top chambers over three consecutive summers. Treatments provided a mean seasonal AOT40 ranging from approximately zero to 15 ppm h. Cumulative ozone exposure was a significant factor in compositional change, but only explained 4.6% of the variation. The dominant grass species (Festuca rubra) showed a consistent decline in cover in the high ozone treatment over time and the forb Campanula rotundifolia was lost from all three ozone treatments. The frequency of some species (Galium verum and Plantago lanceolata) increased with ozone exposure. Long-term effects of ozone on species composition in chalk grassland may be a function of both the sensitivity of individual species and the response of the dominant species. - Exposure of calcareous grassland turfs to ozone for three years resulted in small, but significant, changes in species composition

  20. The effects of tropospheric ozone on the species dynamics of calcareous grassland

    Thwaites, R.H. [Department of Biology, Imperial College, Silwood Park, Ascot, Berkshire SL5 7PY (United Kingdom); Ashmore, M.R. [Environment Department, University of York, Heslington, York YO10 5DD (United Kingdom); Morton, A.J. [Department of Biology, Imperial College, Silwood Park, Ascot, Berkshire SL5 7PY (United Kingdom); Pakeman, R.J. [Ecology of Grazed Ecosystems, Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH (United Kingdom)]. E-mail: r.pakeman@macaulay.ac.uk

    2006-11-15

    Although ozone has been shown to reduce the growth of individual species and to alter the composition of simple species mixtures, there is little understanding of its long-term effects on species dynamics and composition in real communities. Intact turfs of calcareous grassland were exposed to four different ozone regimes in open-top chambers over three consecutive summers. Treatments provided a mean seasonal AOT40 ranging from approximately zero to 15 ppm h. Cumulative ozone exposure was a significant factor in compositional change, but only explained 4.6% of the variation. The dominant grass species (Festuca rubra) showed a consistent decline in cover in the high ozone treatment over time and the forb Campanula rotundifolia was lost from all three ozone treatments. The frequency of some species (Galium verum and Plantago lanceolata) increased with ozone exposure. Long-term effects of ozone on species composition in chalk grassland may be a function of both the sensitivity of individual species and the response of the dominant species. - Exposure of calcareous grassland turfs to ozone for three years resulted in small, but significant, changes in species composition.

  1. Impact of future nitrous oxide and carbon dioxide emissions on the stratospheric ozone layer

    The atmospheric levels of human-produced chlorocarbons and bromocarbons are projected to make only small contributions to ozone depletion by 2100. Increases in carbon dioxide (CO2) and nitrous oxide (N2O) will become increasingly important in determining the future of the ozone layer. N2O increases lead to increased production of nitrogen oxides (NOx), contributing to ozone depletion. CO2 increases cool the stratosphere and affect ozone levels in several ways. Cooling decreases the rate of many photochemical reactions, thus slowing ozone loss rates. Cooling also increases the chemical destruction of nitrogen oxides, thereby moderating the effect of increased N2O on ozone depletion. The stratospheric ozone level projected for the end of this century therefore depends on future emissions of both CO2 and N2O. We use a two-dimensional chemical transport model to explore a wide range of values for the boundary conditions for CO2 and N2O, and find that all of the current scenarios for growth of greenhouse gases project the global average ozone to be larger in 2100 than in 1960. (letter)

  2. Ozone effects on Sphagnum mosses, carbon dioxide exchange and methane emission in boreal peatland microcosms

    Niemi, Riikka; Holopainen, Toini [Department of Ecology and Environmental Science, University of Kuopio, P.O. Box 1627, 70211 Kuopio (Finland); Martikainen, Pertti J. [Department of Environmental Sciences, Bioteknia 2, University of Kuopio, P.O. Box 1627, 70211 Kuopio (Finland); Silvola, Jouko [Department of Biology, University of Joensuu, P.O. Box 111, 80101 Joensuu (Finland)

    2002-04-22

    Microcosms of a boreal peatland originating from an oligotrophic fen in Eastern Finland were fumigated under four ozone concentrations (0, 50, 100 and 150 ppb O{sub 3}) in laboratory growth chambers during two separate experiments (autumn and summer) for 4 and 6 weeks, respectively. Ozone effects on Sphagnum mosses and the fluxes of carbon dioxide and methane were evaluated. In both experiments, the three Sphagnum species studied showed only a few significant responses to ozone. In the autumn experiment, membrane permeability of S. angustifolium, measured as conductivity and magnesium leakage, was significantly higher under ozone fumigation (P=0.005 and <0.001, respectively), and there was a distinct dose-dependence. S. magellanicum showed no clear responses, either for membrane leakage or pigment content. There were no substantial ozone responses in the gross photosynthesis or net CO{sub 2} exchange during the 6-week-long summer experiment, but dark ecosystem respiration was transiently increased by ozone concentration of 100 ppb after 14 days of exposure (P<0.05). Fumigation with 100 ppb of ozone, however, more than doubled (P<0.05) methane emission from the peatland monoliths. Our results suggest that increasing tropospheric ozone concentration may cause substantial changes in the carbon gas cycling of boreal peatlands, even though these changes are not closely associated with the changes in Sphagnum vegetation.

  3. Ambient air pollution and the fetus

    Kadriye Yurdakök

    2013-06-01

    Full Text Available There is a growing evidence on the hazards of ambient air pollution on fetal development. Several review articles have been published on the adverse fetal outcomes including low birth weight, preterm birth, small-for-gestational age, and congenital anomalies. Recent studies have linked ambient air pollution to gestational hypertension, and preeclampsia which may be related to the detrimental effect of ambient air pollution on placental growth and function. Short-term and long-term exposure to particulate air pollution may cause systemic inflammatory response which may trigger preterm delivery in pregnant women. Environmental toxic chemicals that alter intrauterine environment disregulates fetal epigenome causing epigenetic-mediated changes in gene expression that may be linked to later childhood and adulthood diseases. Exposure to ambient air pollution during the whole pregnancy especially in third-trimester may cause intrauterine vitamin D deficiency which is critical for the normal development of the lung, and immune system in fetus. However, more research is needed to understand the cause and effect interaction between air pollution and fetal development. Proceedings of the 9th International Workshop on Neonatology · Cagliari (Italy · October 23rd-26th, 2013 · Learned lessons, changing practice and cutting-edge research

  4. Response of turnips to chronic doses of ozone in open-top field chambers

    Heagle, A.S.; Cure, W.W.; Rawlings, J.O.

    1985-01-01

    Turnips Brassica rapa L., were exposed to chronic doses of ozone (O3) by adding different amounts of O3 for 7 h a day to non-filtered air in open-top field chambers. One cultivar (Tokyo Cross) was tested in 1979 and four cultivars (Tokyo Cross, Shogoin, Purple Top White Globe and Just Right) in 1980. Ambient levels of O3 usually did not affect shoot or root weight in either year. In 1979, seasonal mean O3 levels greater than ambient caused greater percentage growth decreases of Tokyo Cross plants grown in the ground than for plants grown in 3.8 liter pots. In 1980, 7 h a day exposures from 20 October to 14 November to levels as high as 0.16 ppm caused some chlorosis on a few of the oldest leaves of all cultivars. No O3 was added from 15-17 November because the weather was cold, overcast and rainy. Exposures to O3 concentrations of 0.09 or 0.11 ppm for 3 - 5 h on the afternoon of 18 November caused severe foliar necrosis on all expanded leaves of all cultivars. The Weibull survival function was used to predict root weight decreases at different seasonal 7 h a day mean O3 levels using 0.025 ppm O3 as the control. Predicted percentage root weight losses for the four cultivars combined at seasonal O3 levels of 0.04, 0.06 and 0.08 ppm were 7, 24 and 47%, respectively.

  5. Ozone Monitoring Instrument

    de Vries, Johan

    The Ozone Monitoring Instrument is a trace gas monitoring instrument in the line of GOME (ERS-2) and Sciamachy (ENVISAT). Following these instruments, OMI provides UV-visible spectroscopy with a resolution sufficient to separate out the various absorbing trace gases (using DOAS or `Full' retrieval), but shaped as an imaging spectrometer. This means that a two dimensional detector is used where one dimension records the spectrum and the other images the swath. The scanning mechanism from the GOME and Sciamachy is not required anymore and there are considerable advantages with respect to simultaneous measurement of swath pixels, polarisation and obtainable swath width. The OMI consortium for a phase B is formed by Fokker Space & Systems and TPD in the Netherlands and VTT in Finland. In the presentation UV-visible atmospheric remote sensing will be placed in perspective and the OMI will be explaned.

  6. Measures of ozone concentrations using passive sampling in forests of South Western Europe

    Ambient ozone concentrations were measured with passive samplers in the framework of the EU and UN/ECE Level II forest monitoring programme. Data from France, Italy, Luxembourg, Spain and Switzerland are reported for 2000-2002, covering the period from April to September. The number of plots increased from 67 in 2000 to 83 in 2002. The year 2001 experienced the highest ozone concentrations, reflecting more stable summer meteorological conditions. Average 6-month ozone concentrations above 45 ppb were measured this year in 40.3% of the plots, in contrast with the less than 21% measured in the other 2 years. Gradients of increasing ozone levels were observed from North to South and with altitude. Comments are made on the regional trends and on the time frame of the higher ozone episodes. Also, some recommendations enabling a better comparison between plots are provided. - Ozone concentrations in forested areas of SW Europe during the period 2000-2002 showed highest values in 2001, as well as a tendency to increase towards the South and with altitude

  7. Geostatistics as a validation tool for setting ozone standards for durum wheat

    Which is the best standard for protecting plants from ozone? To answer this question, we must validate the standards by testing biological responses vs. ambient data in the field. A validation is missing for European and USA standards, because the networks for ozone, meteorology and plant responses are spatially independent. We proposed geostatistics as validation tool, and used durum wheat in central Italy as a test. The standards summarized ozone impact on yield better than hourly averages. Although USA criteria explained ozone-induced yield losses better than European criteria, USA legal level (75 ppb) protected only 39% of sites. European exposure-based standards protected ≥90%. Reducing the USA level to the Canadian 65 ppb or using W126 protected 91% and 97%, respectively. For a no-threshold accumulated stomatal flux, 22 mmol m-2 was suggested to protect 97% of sites. In a multiple regression, precipitation explained 22% and ozone explained <0.9% of yield variability. - Geostatistics can be used as a tool for testing the effects of ozone standards on plant responses in the field.

  8. Nighttime Chemistry and Morning Isoprene Can Drive Urban Ozone Downwind of a Major Deciduous Forest.

    Millet, Dylan B; Baasandorj, Munkhbayar; Hu, Lu; Mitroo, Dhruv; Turner, Jay; Williams, Brent J

    2016-04-19

    Isoprene is the predominant non-methane volatile organic compound emitted to the atmosphere and shapes tropospheric composition and biogeochemistry through its effects on ozone, other oxidants, aerosols, and the nitrogen cycle. Isoprene is emitted naturally by vegetation during daytime, when its photo-oxidation is rapid, and in the presence of nitrogen oxides (NOx) produces ozone and degrades air quality in polluted regions. Here, we show for a city downwind of an isoprene-emitting forest (St. Louis, MO) that isoprene actually peaks at night; ambient levels then endure, owing to low nighttime OH radical concentrations. Nocturnal chemistry controls the fate of that isoprene and the likelihood of a high-ozone episode the following day. When nitrate (NO3) radicals are suppressed, high isoprene persists through the night, providing photochemical fuel upon daybreak and leading to a dramatic late-morning ozone peak. On nights with significant NO3, isoprene is removed before dawn; days with low morning isoprene then have lower ozone with a more typical afternoon peak. This biogenic-anthropogenic coupling expands the daily high-ozone window and likely has an opposite O3-NOx response to what would otherwise be expected, with implications for exposure and air-quality management in cities that, like St. Louis, are downwind of major isoprene-emitting forests. PMID:27010702

  9. Surface ozone variation at Bhubaneswar and intra-corelationship study with various parameters

    P S Mahapatra; J Jena; S Moharana; H Srichandan; T Das; G Roy Chaudhury; S N Das

    2012-10-01

    This paper summarizes the results of year long (December 2009 to January 2011) continuous measurements of daytime (0700–1745) ozone (O3) in the ambient air and related meteorological parameters at Bhubaneswar (21° 15′N–85° 15′E), Odisha. The seasonal variation shows distinct daytime ozone maxima during winters with a peak in January (∼85 ppbv), a slight increase (∼38 ppbv) in June and lowest in August (∼20 ppbv). The backward trajectory analysis during winter months suggests long distance transport of airmass from mainly Indo-Gangetic Plains (IGP) and western part of Indian peninsula, a major industrial hub. In other seasons, wind reaches the observation site from less polluted landmasses and the Bay of Bengal, thereby considerably reducing the pollution load. On the contrary, ozone build-up was found to be maximum and minimum in pre-monsoon and monsoon, respectively. An anti-weekend ozone effect (∼5 ppbv) was observed in winter. Paired t-test and F-test along with principal component analysis (PCA) were done to determine significance between various components (ozone, precursors and meteorological parameters). The t- and F-test showed significant monthly variation of ozone mixing ratio. The PCA showed that three components explained 79.1% of variances.

  10. Influence of dietary vitamin E on the lungs of ozone-exposed rats

    Chow, C.K.; Plopper, C.G.; Dungworth, D.L.

    1979-12-01

    The effect of dietary vitamin E on pulmonary susceptibility to near ambient levels of ozone was studied in rats. Exposure to 0.7 or 0.8 ppM ozone continuously for 7 days resulted in significant biochemical augmentations in the lungs of both vitamin E-deficient and -supplemented rats. The relative order of the change was glutathione (GSH) peroxidase > lactate dehydrogenase > glucose-6-phosphate (G-6-P) dehydrogenase and pyruvate kinase > reduced glutathione > malic enzyme > glutathione reductase > protein and malic dehydrogenase. Except for malic dehydrogenase, the degrees of biochemical changes were greater in the lungs of vitamin E-deficient rats than those of the supplemented group following ozone exposure, and the differences in the levels of GSH peroxidase, G-6-P dehydrogenase, pyruvate kinase, and GSH were statisically significant. Histological examination of animal lungs revealed that all aminals exposed to 0.7 ppM ozone for 7 days had detectable lesions compared to none from the control groups. However, almost all the lungs categorized as having severe lesions by two investigators in a blind study were from rats fed the vitamin E-deficient diet, while nearly all the lungs from the supplemented group had mild lesions. The results suggest that dietary vitamin E alters cellular sensitivity of lung tissue to ozone exposure, and that depletion of dietary vitamin E lowers the threshold concentration of ozone at which effects can be detected.

  11. Measures of ozone concentrations using passive sampling in forests of South Western Europe

    Sanz, M.J. [Fundacion CEAM, Charles R. Darwin 14, Parc Tecnologic, E-46980 Paterna, Valencia (Spain)]. E-mail: mjose@ceam.es; Calatayud, V. [Fundacion CEAM, Charles R. Darwin 14, Parc Tecnologic, E-46980 Paterna, Valencia (Spain); Sanchez-Pena, G. [Servicio de Proteccion de los Montes contra Agentes Nocivos, Direccion General para la Biodiversidad, Ministerio de Medio Ambiente, Gran Via de San Francisco, 4, E-28005, Madrid (Spain)

    2007-02-15

    Ambient ozone concentrations were measured with passive samplers in the framework of the EU and UN/ECE Level II forest monitoring programme. Data from France, Italy, Luxembourg, Spain and Switzerland are reported for 2000-2002, covering the period from April to September. The number of plots increased from 67 in 2000 to 83 in 2002. The year 2001 experienced the highest ozone concentrations, reflecting more stable summer meteorological conditions. Average 6-month ozone concentrations above 45 ppb were measured this year in 40.3% of the plots, in contrast with the less than 21% measured in the other 2 years. Gradients of increasing ozone levels were observed from North to South and with altitude. Comments are made on the regional trends and on the time frame of the higher ozone episodes. Also, some recommendations enabling a better comparison between plots are provided. - Ozone concentrations in forested areas of SW Europe during the period 2000-2002 showed highest values in 2001, as well as a tendency to increase towards the South and with altitude.

  12. Mechanisms of impact of greenhouse gases on the Earth's ozone layer in the Polar Regions

    Zadorozhny, Alexander; Dyominov, Igor

    A numerical 2-D zonally averaged interactive dynamical radiative-photochemical model of the atmosphere including aerosol physics is used to examine the impact of the greenhouse gases CO2, CH4, and N2O on the future long-term changes of the Earth's ozone layer, in particular on its expected recovery after reduction of anthropogenic discharges of chlorine and bromine compounds into the atmosphere. The model allows calculating self-consistently diabatic circu-lation, temperature, gaseous composition of the troposphere and stratosphere at latitudes from the North to South Poles, as well as distribution of sulphate aerosol particles and polar strato-spheric clouds (PSCs) of types I and II. The scenarios of expected changes of the anthropogenic pollutants for the period from 1980 through 2050 are taken from Climate Change 2001. The processes, which determine the influence of anthropogenic growth of atmospheric abun-dance of the greenhouse gases on the long-term changes of the Earth's ozone layer in the Polar Regions, have been studied in details. Expected cooling of the stratosphere caused by increases of greenhouse gases, most importantly CO2, essentially influences the ozone layer by two ways: through temperature dependencies of the gas phase reaction rates and through enhancement of polar ozone depletion via increased PSC formation. The model calculations show that a weak-ness in efficiencies of all gas phase catalytic cycles of the ozone destruction due to cooling of the stratosphere is a dominant mechanism of the impact of the greenhouse gases on the ozone layer in Antarctic as well as at the lower latitudes. This mechanism leads to a significant acceleration of the ozone layer recovery here because of the greenhouse gases growth. On the contrary, the mechanism of the impact of the greenhouse gases on the ozone through PSC modification be-gins to be more effective in Arctic in comparison with the gas phase mechanism in springs after about 2020, which leads to retard

  13. Arquitectura y medio ambiente

    Saura Carulla, Magdalena

    2003-01-01

    La arquitectura y la planificación son el resultado de una integración ponderada de conocimientos técnicos y una multiplicidad de aspectos relacionados con el conocimiento natural y social. En este trabajo el autor propone, desde el ámbito de las ciencias del medio ambiente, diversos planteamientos teóricos y prácticos relacionados con la arquitectura y el urbanismo. El conocimiento de la naturaleza de los sistemas naturales y de los sistemas ecosociales permite al diseñador aplicar un marco ...

  14. Ambiente il nostro futuro

    Canigiani, Franca

    2016-01-01

    L’ambiente è il quadro di vita, la casa comune, il patrimonio di base delle società umane – scriveva un indimenticabile maestro della geografia italiana: Giuseppe Barbieri. Due gli avvenimenti che nel 2015 hanno segnato il passo dell’umanità sulla strada di una più matura coscienza ambientale, fino a comprendere che è necessario e urgente prendersi cura della Terra: primo, la pubblicazione della lettera enciclica di papa Francesco, Laudato si’ sulla cura della casa comune, straordinario saggi...

  15. AOX y medio ambiente.

    Riva Juan, Mª del Carmen; López Ribas, David

    1996-01-01

    Los productos organohalogenados son muy utilizados por la industria y su presencia en el medio ambiente está siendo controlada. En los últimos años se han desarrollado varias técnicas de detección, siendo desde finales de los 80 los AOX (adsorbable organic halogens) uno de los parámetros sobre los que se han realizado más estudios. En muchos paises de la Unión Europea y en E.E.U.U. de América, la presencia de compuestos organohalogenados en aguas continentales y suelos está legislada indicand...

  16. Ozone emergency in Venetian land

    The events exceeding the level of attention for ozone detected on the venetian land on a period of 6 and 4 years respectively by two stationary observatories, the ones located in the industrial zone and the other in a semi-rural, completed by data detected by three mobile observatories, have been correlated with space-temporal, atmospheric and relative chemical pollution parameters. The analysis of the data allowed: a) the estimation of the state of the air of the venetian land, with reference to the ozone pollution; b) the information of the hours, days and month of greatest risk and the meteorological situations which give high concentration levels of this polluting substance; c) the suggestion of a model of formation and dispersion of the ozone; d) the ascertainment of a higher ozone risk on zone relatively remote from the polluting sources

  17. Evaluation of antifungal effect of gaseous ozone in a meat processing plant

    Lisa Vallone

    2014-06-01

    Full Text Available Ozone is already known as effective food/environmental disinfection agent, thanks to its oxidative action towards microbial cell components. Bactericidal effect of ozone is well documented, while data concerning its inhibitory activity towards fungi are still ambiguous. Our study aims to evaluate the antimicrobial activity of gaseous ozone towards potentially contaminant fungi in a meat production plant in real working conditions. M2 and M5S5 plates were inoculated with Aspergillus niger, Penicillium roqueforti, Mucor racemosus, Saccharomyces cerevisiae strains and positioned in a deboning room, where gaseous ozone was dispensed throughout the night (until a maximum concentration of 20 ppm. Nine different points were chosen, based on height and distance from the ozone dispenser. After the treatment, the presence of strains growth was evaluated. Gaseous ozone did not show any inhibitory activity against mould strains, as optimum growth during all the trials was observed. An appreciable and constant microbicidal effect against S. cerevisiae was evidenced, with a mean value of 2.8 Log reduction. Our results suggest the importance of the definition of environmental and technical use conditions in order to optimise the antimicrobial efficacy of ozone in real working situations in food industries.

  18. Evaluation of the Community Multiscale Air Quality Model for Simulating Winter Ozone Formation in the Uinta Basin

    Areas with close proximity to oil and natural gas operations in rural Utah have experienced winter ozone levels that exceed EPA’s National Ambient Air Quality Standards (NAAQS). Through a collaborative effort, EPA Region 8 – Air Program, ORD, and OAQPS used the Commun...

  19. Ambient air quality observations in the Athabasca oil sands region

    Both Syncrude and Suncor have plans to develop new oil sands leases and to increase crude oil and bitumen recovery in the Athabasca oil sands region. In recognition of the effects that this will have on the environment, Suncor has proposed modifications to reduce SO2 emissions to the atmosphere, while Syncrude plans to develop additional ambient air quality, sulphur deposition and biomonitoring programs. This report discussed the ambient air quality monitoring that was undertaken in the Fort McMurray-Fort McKay airshed. Twelve continuous ambient air quality stations and 76 passive monitoring stations are maintained in the region. Environment Canada maintains eight precipitation monitoring stations in northern Alberta and Saskatchewan. Source characterization, ambient air quality and meteorology observations, air quality monitoring, and air quality data from continuous sulphur dioxide, hydrogen sulphide, nitrogen oxides, ozone, carbon monoxide, hydrocarbon, acid rain and particulates analyzers were reviewed. The documentation of all computer files used for the analysis of the air quality data is discussed in the Appendix. 47 refs., 39 tabs., 53 figs

  20. Ethylenediurea (EDU): A research tool for assessment and verification of the effects of ground level ozone on plants under natural conditions

    Manning, William J. [Department of Plant, Soil and Insect Sciences, University of Massachusetts, Amherst, MA 01003-9320 (United States); Paoletti, Elena, E-mail: e.paoletti@ipp.cnr.it [IPP CNR, Via Madonna del Piano 10, I-50019 Sesto Fiorentino (Italy); Sandermann, Heinrich [ecotox.freiburg, Schubertstr. 1, D-79104 Freiburg (Germany); Helmholtz Zentrum Muenchen, German Research Center for Environmental Health, Institute of Biochemical Plant Pathology, D-85764 Neuherberg (Germany); Ernst, Dieter [ecotox.freiburg, Schubertstr. 1, D-79104 Freiburg (Germany)

    2011-12-15

    Ethylenediurea (EDU) has been widely used to prevent ozone (O{sub 3}) injury and crop losses in crop plants and growth reductions in forest trees. Successful use requires establishing a dose/response curve for EDU and the proposed plant in the absence of O{sub 3} and in the presence of O{sub 3} before initiating multiple applications to prevent O{sub 3} injury. EDU can be used to verify foliar O{sub 3} symptoms in the field, and to screen plants for sensitivity to O{sub 3} under ambient conditions. Despite considerable research, the mode of action of EDU remains elusive. Additional research on the mode of action of EDU in suppressing O{sub 3} injury in plants may also be helpful in understanding the mode of action of O{sub 3} in causing injury in plants. - EDU is a verified and effective tool for the assessment of the effects of ozone on plants.

  1. The Ozone Component of Global Change:Potential Effects on Agricultural and Horticultural Plant Yield,Product Quality and Interactions with Invasive Species

    Fitzgerald Booker; Russell Muntifering; Margaret McGrath; Kent Burkey; Dennis Decoteau; Edwin Fiscus; William Manning; Sagar Krupa; Arthur Chappelka; David Grantz

    2009-01-01

    The productivity,product quality and competitive ability of important agricultural and horticultural plants in many regions of the world may be adversely affected by current and anticipated concentrations of groundlevel ozone (O3).Exposure to elevated O3 typically results in suppressed photosynthesis,accelerated senescence,decreased growth and lower yields.Various approaches used to evaluate O3 effects generally concur that current yield losses range from 5% to 15% among sensitive plants.There is,however,considerable genetic variability in plant responses to O3.To illustrate this,we show that ambient O3 concentrations in the eastern United States cause substantially different levels of damage to otherwise similar snap bean cultivars.Largely undesirable effects of O3 can also occur in seed and fruit chemistry as well as in forage nutritive value,with consequences for animal production.Ozone may alter herbicide efficacy and foster establishment of some invasive species.We conclude that current and projected levels of O3 in many regions worldwide are toxic to sensitive plants of agricultural and horticultural significance.Plant breeding that incorporates O3 sensitivity into selection strategies will be increasingly necessary to achieve sustainable production with changing atmospheric composition,while reductions in O3 precursor emissions will likely benefit world food production and reduce atmospheric concentrations of an important greenhouse gas.

  2. Ozone phytotoxicity in relation to stress ethylene evolution and stomatal resistance in cowpea (Vigna unguiculata) cultivars

    Adepipe, N.O.; Tingey, D.T.

    1979-01-01

    In greenhouse experiments, the ozone sensitivities of three cowpea cultivars differing in growth habits and some physiological traits were determined and related to stress ethylene production and leaf diffusive resistance. The cultivars were more sensitive at the 3-leaf than at the 2-leaf stages of growth. There was no consistent leaf injury at less than 0.50 ..mu..l/l of ozone for 2 hr. At an ozone concentration of 1.0 ..mu..l/l for 2 hr. the cultivar Adzuki exhibited marked leaf injury, amounting to over 80% symptom coverage of the leaf surface while New Era and Ife Brown sustained leaf injury maxima of 58 and 35% respectively. Stress ethylene production did not differ among the cultivars. While ozone increased stomatal diffusive resistance in all cultivars, there were not significant differences among the cultivars.

  3. Ozone Applications in Food Industry

    (Doğan), Elif Savaş; Hakan Tavşanlı; İlhan Gökgözoğlu

    2014-01-01

    Known as active oxygen Ozone (O3), are among the most effective antimicrobials. The sun's ultraviolet rays and ozone caused by electric arcs of lightning occurring instantly around the world, and is available as a protective shield protects the animals against the effects of the sun's radiation. In the food industry, directly or indirectly in contact with food during processing of foods and chemical treatment of water disinfection bacteriological emerges as an alternative protection method. I...

  4. Ozone promoters situation in Austria

    An analysis of the main ozone promoters (volatile organic compounds (NMVOC), NOx and CO) emissions in Austria was performed and the results were compared against international and national limits (Austrian ozone law). This analysis covered the trends in the years 1990-2002. 204,000 tons of nitrogen oxides (NOx), 193,000 tons of volatile organic compounds (NMVOC) and 812,000 tons of carbon monoxide (CO) were emitted in 2002. 6 figs. (nevyjel)

  5. Developing consistent data and methods to measure the public health impacts of ambient air quality for Environmental Public Health Tracking: progress to date and future directions

    Talbot, Thomas O.; Haley, Valerie B; Dimmick, W. Fred; Paulu, Chris; Evelyn O. Talbott; Rager, Judy

    2009-01-01

    Environmental Public Health Tracking (EPHT) staff at the state and national levels are developing nationally consistent data and methods to estimate the impact of ozone and fine particulate matter on hospitalizations for asthma and myocardial infarction. Pilot projects have demonstrated the feasibility of pooling state hospitalization data and linking these data to The United States Environmental Protection Agency (EPA) statistically based ambient air estimates for ozone and fine particulates...

  6. Crisis ambiental y cristianismo

    Felipe Cárdenas

    2008-01-01

    Full Text Available En el artículo se identifican y reconocen algunas opciones que se pueden desarrollar en el cristianismo en relación con la problemática ambiental. Se aborda el dilema bíblico suscitado por interpretaciones antiecológicas y ecológicas. Con base en una lectura de la Biblia, de testimonios cristianos, y en una rememoria de estructuras institucionales, como la parroquia, se analiza el valor que tiene el mensaje cristiano en lo referido a la mitigación de la crisis ambiental.This article identifies and recognizes some options that can be developed in Christianity in relation to the environmental problem. It starts by analyzing the biblical dilemma provoked by both ecological and antiecological interpretations. Based on a reading of the Bible, testimonies from Christians and with a rememory of institutional structures, like the parish, the valué of the Christian message for mitigating the environmental crisis is analyzed.

  7. Effects of Gaseous Ozone Exposure on Bacterial Counts and Oxidative Properties in Chicken and Duck Breast Meat

    Muhlisin, Muhlisin; Utama, Dicky Tri; Lee, Jae Ho; Choi, Ji Hye; Lee, Sung Ki

    2016-01-01

    The effects of gaseous ozone exposure on the bacterial counts and oxidative properties were evaluated in duck and chicken breast fillets, which were stored under a continuous flux of gaseous ozone (10×10−6 kg O3/m3/h) at 4±1℃ for 4 d. The ozone generator was set to on for 15 min and off for 105 min, and this cyclic timer was set during storage. Ozone effectively reduced the growth of coliform, aerobic and anaerobic bacteria in both chicken and duck breast. However, lipid oxidation occurred faster in duck breast than chicken breast with higher degree of discoloration, TBARS value, and antioxidant enzyme (glutathione peroxidase and catalase) activity decline rates. It is concluded that ozone effectively controlled the growth of bacteria in both chicken and duck breast with less effects on oxidative deterioration in chicken breast.

  8. Effects Of Elevated Ozone On Leaf {delta} {sup 13} C And Leaf Conductance Of Plant Species Grown In Semi-Natural Grassland With Or Without Irrigation

    Jaeggi, M.; Saurer, M.; Volk, M. [Agroscope-FAL (Switzerland); Fuhrer, J. [Agroscope-FAL (Switzerland)

    2005-03-01

    At the Swiss prealpine site Le Mouret (754 m a.s.l. 46deg 45min N / 7deg 10min E), semi-natural grassland species were kept under ambient or elevated ozone, paired with or without additional irrigation. Two of the four investigated grassland species showed an additive increase in {sup 13}C-values under drought and elevated ozone conditions. (author)

  9. The role of phytohormone signaling in ozone-induced cell death in plants

    Tamaoki, Masanori

    2008-01-01

    Ozone is the main photochemical oxidant that causes leaf damage in many plant species, and can thereby significantly decrease the productivity of crops and forests. When ozone is incorporated into plants, it produces reactive oxygen species (ROS), such as superoxide radicals and hydrogen peroxide. These ROS induce the synthesis of several plant hormones, such as ethylene, salicylic acid, and jasmonic acid. These phytohormones are required for plant growth, development, and defense responses, ...

  10. Tropospheric ozone (TOR) trend over three major inland Indian cities: Delhi, Hyderabad and Bangalore

    Pavan S. Kulkarni; Sachin D. Ghude; D. Bortoli

    2010-01-01

    An analysis of tropospheric column ozone using the NASA Langley TOR data during 1979–2005 has been done to investigate the trend over major Indian cities Delhi, Hyderabad and Bangalore. India was under social democratic-based policies before 1990s. Economic Liberalization began in nineties which lead to a significant growth in industrial, energy and transport sectors in major cities. Our analysis shows that there is a systematic increase in the number of months with higher tropospheric ozone ...

  11. Scientific assessment of ozone depletion: 1991

    1991-01-01

    Over the past few years, there have been highly significant advances in the understanding of the impact of human activities on the Earth's stratospheric ozone layer and the influence of changes in chemical composition of the radiative balance of the climate system. Specifically, since the last international scientific review (1989), there have been five major advances: (1) global ozone decreases; (2) polar ozone; (3) ozone and industrial halocarbons; (4) ozone and climate relations; and (5) ozone depletion potentials (ODP's) and global warming potentials (GWP's). These topics and others are discussed.

  12. Types for BioAmbients

    Capecchi, Sara; 10.4204/EPTCS.19.7

    2010-01-01

    The BioAmbients calculus is a process algebra suitable for representing compartmentalization, molecular localization and movements between compartments. In this paper we enrich this calculus with a static type system classifying each ambient with group types specifying the kind of compartments in which the ambient can stay. The type system ensures that, in a well-typed process, ambients cannot be nested in a way that violates the type hierarchy. Exploiting the information given by the group types, we also extend the operational semantics of BioAmbients with rules signalling errors that may derive from undesired ambients' moves (i.e. merging incompatible tissues). Thus, the signal of errors can help the modeller to detect and locate unwanted situations that may arise in a biological system, and give practical hints on how to avoid the undesired behaviour.

  13. Types for BioAmbients

    Sara Capecchi

    2010-02-01

    Full Text Available The BioAmbients calculus is a process algebra suitable for representing compartmentalization, molecular localization and movements between compartments. In this paper we enrich this calculus with a static type system classifying each ambient with group types specifying the kind of compartments in which the ambient can stay. The type system ensures that, in a well-typed process, ambients cannot be nested in a way that violates the type hierarchy. Exploiting the information given by the group types, we also extend the operational semantics of BioAmbients with rules signalling errors that may derive from undesired ambients' moves (i.e. merging incompatible tissues. Thus, the signal of errors can help the modeller to detect and locate unwanted situations that may arise in a biological system, and give practical hints on how to avoid the undesired behaviour.

  14. Exposure to ozone reduces influenza disease severity and alters distribution of influenza viral antigens in murine lungs.

    Wolcott, J A; Zee, Y C; Osebold, J W

    1982-09-01

    Exposure to ambient levels of ozone (0.5 ppm) was shown to alter the pathogenesis of respiratory infection after aerosol infection of mice with influenza A virus. A semiquantitative method for determination of the sites of virus replication by direct immunofluorescence indicated that exposure to ozone reduced the involvement of respiratory epithelium in the infectious process and resulted in a less widespread infection of the alveolar parenchyma. Furthermore, the ozone-mediated alteration in viral antigen distribution was consistent with significantly reduced influenza disease mortality and prolonged survival time, but only when the oxidant was present during the course of infection. Reduced disease severity in ozone-exposed animals appeared to be independent of peak pulmonary virus titers, pulmonary interferon titers, and pulmonary and serum-neutralizing antibody titers. These studies suggested that the distribution of influenza virus in the murine lung was a key factor in disease severity. PMID:6182839

  15. Herbivore-mediated material fluxes in a northern deciduous forest under elevated carbon dioxide and ozone concentrations.

    Meehan, Timothy D; Couture, John J; Bennett, Alison E; Lindroth, Richard L

    2014-10-01

    Anthropogenic changes in atmospheric carbon dioxide (CO2 ) and ozone (O3 ) are known to alter tree physiology and growth, but the cascading effects on herbivore communities and herbivore-mediated nutrient cycling are poorly understood. We sampled herbivore frass, herbivore-mediated greenfall, and leaf-litter deposition in temperate forest stands under elevated CO2 (c. 560 ppm) and O3 (c. 1.5× ambient), analyzed substrate chemical composition, and compared the quality and quantity of fluxes under multiple atmospheric treatments. Leaf-chewing herbivores fluxed 6.2 g m(-2)  yr(-1) of frass and greenfall from the canopy to the forest floor, with a carbon : nitrogen (C : N) ratio 32% lower than that of leaf litter. Herbivore fluxes of dry matter, C, condensed tannins, and N increased under elevated CO2 (35, 32, 63 and 39%, respectively), while fluxes of N decreased (18%) under elevated O3 . Herbivore-mediated dry matter inputs scaled across atmospheric treatments as a constant proportion of leaf-litter inputs. Increased fluxes under elevated CO2 were consistent with increased herbivore consumption and abundance, and with increased plant growth and soil respiration, previously reported for this experimental site. Results suggest that insect herbivory will reinforce other factors, such as photosynthetic rate and fine-root production, impacting C sequestration by forests in future environments. PMID:25078062

  16. Temporal Variations in Concentrations of Ozone, Nitrogen Dioxide, and Carbon Monoxide at Osijek, Croatia

    Elvira Kovač-Andrić

    2013-01-01

    Full Text Available The purpose of this study was to investigate the ozone, carbon monoxide, and nitrogen dioxide variations and their correlation with meteorological parameters in Osijek (Eastern Croatia during the summer seasons of 2002, 2007, and 2012. The measured data are discussed in relation to the EU guidelines (Directive 2002/3/EC, Directive 2008/50/EC. In order to characterize ambient air with respect to ozone photochemical pollution we calculated three photochemical pollution indicators. These indicators may also be a valid measure for harmful effects on living organisms. The influence of local meteorological parameters on the measured concentrations of ozone, carbon monoxide, and nitrogen dioxide was also investigated. We have attempted to establish correlations between measured pollutant concentrations and meteorological parameters using the technique of multivariate principal component analysis (PCA.

  17. Cost-Effective Control of Ground-Level Ozone Pollution in and around Beijing

    Xie Xuxuan; Zhang Shiqiu; Xu Jianhua; Wu Dan; Zhu Tong

    2012-01-01

    Ground level ozone pollution has become a significant air pollution problem in Beijing. Because of the complex way in which ozone is formed, it is difficult for policy makers to identify optimal control options on a cost-effective basis. This paper identi- fies and assesses a range of options for addressing this problem. We apply the Ambient Least Cost Model and compare the eco- nomic costs of control options, then recommend the most effective sequence to realize pollution control at the lowest cost. The study finds that installing of Stage II gasoline vapor recovery system at Beijing's 1446 gasoline stations would be the most cost-effective option. Overall, options to reduce ozone pollution by cutting ve- hicular emissions are much more cost-effective than options to "clean up" coal-fired power plants.

  18. Issues in Stratospheric Ozone Depletion.

    Lloyd, Steven Andrew

    Following the announcement of the discovery of the Antarctic ozone hole in 1985 there have arisen a multitude of questions pertaining to the nature and consequences of polar ozone depletion. This thesis addresses several of these specific questions, using both computer models of chemical kinetics and the Earth's radiation field as well as laboratory kinetic experiments. A coupled chemical kinetic-radiative numerical model was developed to assist in the analysis of in situ field measurements of several radical and neutral species in the polar and mid-latitude lower stratosphere. Modeling was used in the analysis of enhanced polar ClO, mid-latitude diurnal variation of ClO, and simultaneous measurements of OH, HO_2, H_2 O and O_3. Most importantly, such modeling was instrumental in establishing the link between the observed ClO and BrO concentrations in the Antarctic polar vortex and the observed rate of ozone depletion. The principal medical concern of stratospheric ozone depletion is that ozone loss will lead to the enhancement of ground-level UV-B radiation. Global ozone climatology (40^circS to 50^ circN latitude) was incorporated into a radiation field model to calculate the biologically accumulated dosage (BAD) of UV-B radiation, integrated over days, months, and years. The slope of the annual BAD as a function of latitude was found to correspond to epidemiological data for non-melanoma skin cancers for 30^circ -50^circN. Various ozone loss scenarios were investigated. It was found that a small ozone loss in the tropics can provide as much additional biologically effective UV-B as a much larger ozone loss at higher latitudes. Also, for ozone depletions of > 5%, the BAD of UV-B increases exponentially with decreasing ozone levels. An important key player in determining whether polar ozone depletion can propagate into the populated mid-latitudes is chlorine nitrate, ClONO_2 . As yet this molecule is only indirectly accounted for in computer models and field

  19. Toward a Quantitative Assessment of the Influence of Regional Emission Sources on Ozone Production in the Colorado Front Range

    McDuffie, E. E.; Dube, W. P.; Wolfe, D. E.; Tevlin, A.; Gilman, J.; Lerner, B. M.; De Gouw, J. A.; Murphy, J. G.; Fischer, E. V.; Brown, S. S.; Angevine, W. M.; Edwards, P.; Williams, E. J.

    2015-12-01

    Photochemical ozone production results from the oxidation and reaction of volatile organic compounds (VOCs) with nitrogen oxides (NOx = NO2 + NO). As with many US urban regions, ozone levels observed in the Northern Front Range Metropolitan Region of Colorado are influenced by urban emissions of NOx and VOCs. Despite nationwide decreases in these urban emissions, the Front Range of Colorado is one of the few US locations where ozone is currently increasing. It has also recently gone out of compliance with national ambient air quality standards for ozone during summer months. High ozone in Colorado may result from a number of factors, including long-range transport from Asia, increased influence of biomass burning, population increases, or increased emissions from oil and gas activities. The Front Range is home to the Denver-Julesburg (D-J) Basin, which has recently been experiencing a rise in oil and natural gas (O&NG) activity associated with the increase in non-conventional drilling techniques. The VOC and NOx emissions from O&NG activity in close proximity to the urban area may uniquely influence ozone in this region. This presentation will focus on using reactive nitrogen (NOx, NOy) and ozone measurements from a tall (300 m) tower to study the influence of local emissions on Front Range ozone. The tower is located between the D-J Basin and agricultural areas to the north and the Denver metro area to the south. In-situ reactive nitrogen and ozone measurements were collected using a custom Cavity Ring-Down instrument. Additional CH4, CO, and NH3 measurements from the tower serve as tracers for O&NG, urban, and agricultural emissions. Concurrently measured aircraft data is used to confirm the relationships between the tracer species. This presentation will discuss methods for determining the contributions of different emission sources to Front Range ozone, with a focus on differentiating the influence of urban and O&NG sources.

  20. Evidence for an increase in the ozone photochemical lifetime in the eastern United States using a regional air quality model

    Goldberg, Daniel L.; Vinciguerra, Timothy P.; Hosley, Kyle M.; Loughner, Christopher P.; Canty, Timothy P.; Salawitch, Ross J.; Dickerson, Russell R.

    2015-12-01

    Measures to control surface ozone rely on quantifying production attributable to local versus regional (upwind) emissions. Here we simulate the relative contribution of local (i.e., within a particular state) and regional sources of surface ozone in the eastern United States (66-94°W longitude) for July 2002, 2011, and 2018 using the Comprehensive Air-quality Model with Extensions (CAMx). To determine how emissions and chemistry within the domain affect the production, loss, lifetime, and transport of trace gases, we initialize our model with identical boundary conditions in each simulation. We find that the photochemical lifetime of ozone has increased as emissions have decreased. The contribution of ozone from outside the domain (boundary condition ozone, BCO3) to local surface mixing ratios increases in an absolute sense by 1-2 ppbv between 2002 and 2018 due to the longer lifetime of ozone. The photochemical lifetime of ozone lengthens because the two primary gas phase sinks for odd oxygen (Ox ≈ NO2 + O3)—attack by hydroperoxyl radicals (HO2) on ozone and formation of nitrate—weaken with decreasing pollutant emissions. The relative role of BCO3 will also increase. For example, BCO3 represents 34.5%, 38.8%, and 43.6% of surface ozone in the Baltimore, MD, region during July 2002, 2011, and 2018 means, respectively. This unintended consequence of air quality regulation impacts attainment of the National Ambient Air Quality Standard for surface ozone because the spatial and temporal scales of photochemical smog increase; the influence of pollutants transported between states and into the eastern U.S. will likely play a greater role in the future.

  1. Subacute Inhalation Exposure to Ozone Induces Systemic Inflammation but not Insulin Resistance in a Diabetic Mouse Model

    Ying, Zhekang; Allen, Katryn; Zhong, Jixin; Chen, Minjie; Williams, Keisha M.; Wagner, James G.; Lewandowski, Ryan; Sun, Qinghua; Rajagopalan, Sanjay; Harkema, Jack R.

    2016-01-01

    Epidemiological studies suggest that diabetics may be more susceptible to the adverse health effects from exposure to high ambient concentrations of ozone, the primary oxidant gas in photochemical smog. While increased morbidity and mortality from ozone inhalation has been linked to disruption of normal cardiovascular and airway functions, potential effects on glucose and insulin homeostasis are not understood. We tested the hypothesis that ozone exposure would worsen metabolic homeostasis in KKAy mice, a genetic diabetic animal model. Male KKAy mice were exposed to 0.5 ppm ozone for thirteen consecutive weekdays, and then assessed for airway, adipose and systemic inflammation, glucose homeostasis, and insulin signaling. Ozone exposure caused increased plasma TNFα, as well as expression of VCAM-1, iNOS and IL-6 in both pulmonary and adipose tissues. Pro-inflammatory CD11b+Gr-1lo7/4hi macrophages were increased 200% in adipose tissue but unchanged in blood. Interestingly, glucose levels were not significantly different in the insulin tolerance test between air and ozone-expose mice, whereas fasting insulin levels and HOMA-IR in ozone-exposed animals were significantly reduced. These changes were accompanied by increased insulin signaling in skeletal muscle and liver, but not adipose tissues. Ozone also caused decreases in body weight and plasma leptin. Our results show that in addition to marked local and systemic inflammation, ozone increases insulin sensitivity that may be related to weight loss/leptin sensitization-dependent mechanisms in KKAy mice, warranting further study on the role of hyperglycemia in mediating cardiometabolic effects of ozone inhalation. PMID:26986950

  2. Tropospheric ozone columns and ozone profiles for Kiev in 2007

    Shavrina, A V; Sheminova, V A; Synyavski, I I; Romanyuk, Ya O; Eremenko, N A; Ivanov, Yu S; Monsar, O A; Kroon, M

    2010-01-01

    We report on ground-based FTIR observations being performed within the framework of the ESA-NIVR-KNMI project 2907 entitled "OMI validation by ground based remote sensing: ozone columns and atmospheric profiles" for the purpose of OMI data validation. FTIR observations were performed during the time frames August-October 2005, June-October 2006 and March-October 2007, mostly under cloud free and clear sky conditions and in some days from early morning to sunset covering the full range of solar zenith angles possible. Ozone column and ozone profile data were obtained for the year 2005 using spectral modeling of the ozone spectral band profile near 9.6 microns with the MODTRAN3 band model based on the HITRAN-96 molecular absorption database. The total ozone column values retrieved from FTIR observations are biased low with respect to OMI-DOAS data by 8-10 DU on average, where they have a relatively small standard error of about 2%. FTIR observations for the year 2006 were simulated by MODTRAN4 modeling. For the...

  3. Problems of ozone layer monitoring and it protection in Kazakhstan

    Problems of ozone-measuring and study of atmospheric ozone in Kazakhstan are considered. Assessment of stratospheric ozone above Kazakhstan territory is given. Supreme significance in the field ozone layer protection is giving to Kazakhstan joining to International agreements on regulation of supplying of ozone-destroying substances and transition on ozone-safety technologies

  4. Reforma constitucional y ambiente

    Teodoro Bustamante

    2013-09-01

    Full Text Available América Latina está atravesada por una ola de reformas constitucionales. Sus causas, las expectativas que ellas despiertan, los riesgos que se han asociado al proceso de lucha política en su entorno, son temas de un análisis fundamentalmente político; pero hay algunos aspectos en los cuales ese debate tiene una directa repercusión sobre el tema ambiental. En el caso del Ecuador, esto se refleja en el hecho de que una de las innovaciones que se proponen, se refieren a una nueva forma de abordar los temas ambientales, básicamente se establecen Derechos de la Naturaleza.

  5. MEIO AMBIENTE E DESENVOLVIMENTO

    Suely Salgueiro Chacon; Daniel Rodriguez de Carvalho Pinheiro; Francisco Correia de Oliveira; Elizabeth Castelo Branco de Souza

    2009-01-01

    O objetivo deste artigo é resgatar elementos para subsidiar uma reflexão crítica sobre o modelo de desenvolvimento econômico prevalente na sociedade e as relações com o meio ambiente, sob a ameaça que ronda o destino da espécie humana, conforme afirmação de Lovelock (2006, p. 20) sobre o conceito de desenvolvimento sustentável: “uma ideia adorável se a tivéssemos aplicado 200 anos atrás, quando havia um bilhão de pessoas no mundo. Agora é tarde demais. Não há mais espaço para nenhum tipo de d...

  6. Spatial observation of the ozone layer

    Godin-Beekmann, Sophie

    2010-04-01

    This article provides an overview of the various satellite instruments, which have been used to observe stratospheric ozone and other chemical compounds playing a key role in stratospheric chemistry. It describes the various instruments that have been launched since the late 1970s for the measurement of total ozone column and ozone vertical profile, as well as the major satellite missions designed for the study of stratospheric chemistry. Since the discovery of the ozone hole in the early 1980s, spatial ozone measurements have been widely used to evaluate and quantify the spatial extension of polar ozone depletion and global ozone decreasing trends as a function of latitude and height. Validation and evaluation of satellite ozone data have been the subject of intense scientific activity, which was reported in the various ozone assessments of the state of the ozone layer published after the signature of the Montreal protocol. Major results, based on satellite observations for the study of ozone depletion at the global scale and chemical polar ozone loss, are provided. The use of satellite observations for the validation of chemistry climate models that simulate the recovery of the ozone layer and in data assimilation is also described.

  7. Study of ozone "weekend effect" in Shanghai

    TANG WenYuan; ZHAO ChunSheng; GENG FuHai; PENG Li; ZHOU GuangQiang; GAO Wei; XU JianMing; TIE XueXi

    2008-01-01

    Analysis of observed ozone data in 2006 from five monitoring sites (Xujiahui, Chongming, Baoshan, Pudong, Jinshan) in Shanghai reveals that ozone (O3) concentrations in Xujiahui are higher at weekends than those on weekdays, despite the fact that emissions of ozone precursor substances, such as oxides of nitrogen (NOX), carbon monoxide (CO) and volatile organic compounds (VOCs) are lower at weekends than those on weekdays.The possible chemical cause of ozone "weekend effect" is that NO2/NO ratio increases at weekends by 25.61% compared with those on weekdays.In addition, because of an average 12.13% reduction in NOx (NO + NO2) in the early morning (05:00-09:00) at weekends compared with that on weekdays, the ozone inhibition period ends 0.5 h earlier at weekends resulting in the longer duration of ozone accumulation and the higher ozone production rate.The rate of ozone production is a function of VOCs and NOx in the atmosphere.VOCs/NOx ratio in Xujiahui is 4.55 at weekends, and 4.37 on weekdays, belonging to the "NOx-limited".The increasing VOCs/NOx ratio at weekends leads to ozone enhancement from 73 ppbv to 80 ppbv, which are consistent with ozone "weekend effect" in Xujiahui.Furthermore, combining with MICAPS cloud amount data, the fact that ozone "weekend effect" in Xujiahui weakens gradually along with the increasing of cloud amount indicates that ozone photochemical production leads to ozone "weekend effect" in Xujiahui of Shanghai.

  8. Emission sources contributing to tropospheric ozone over Equatorial Africa during the summer monsoon

    I. Bouarar

    2011-12-01

    Full Text Available A global chemistry-climate model LMDz_INCA is used to investigate the contribution of African and Asian emissions to tropospheric ozone over Central and West Africa during the summer monsoon. The model results show that ozone in this region is most sensitive to lightning NOx and to Central African biomass burning emissions. However, other emission categories also contribute significantly to regional ozone. The maximum ozone changes due to lightning NOx occur in the upper troposphere between 400 hPa and 200 hPa over West Africa and downwind over the Atlantic Ocean. Biomass burning emissions mainly influence ozone in the lower and middle troposphere over Central Africa, and downwind due to westward transport. Biogenic emissions of volatile organic compounds, which can be uplifted from the lower troposphere to higher altitudes by the deep convection that occurs over West Africa during the monsoon season, lead to maximum ozone changes in the lower stratosphere region. Soil NOx emissions over the Sahel region make a significant contribution to ozone in the lower troposphere. In addition, convective uplift of these emissions and subsequent ozone production are also an important source of ozone in the upper troposphere over West Africa. Concerning African anthropogenic emissions, they only make a small contribution to ozone compared to the other emission categories. The model results indicate that most ozone changes due to African emissions occur downwind, especially over the Atlantic Ocean, far from the emission regions. The import of Asian emissions also makes a considerable contribution to ozone concentrations above 150 hPa and has to be taken into account in studies of the ozone budget over Africa. Using IPCC AR5 (Intergovernmental Panel on Climate Change; Fifth Assessment Report estimates of anthropogenic emissions for 2030 over Africa and Asia, model calculations show larger changes in ozone over Africa due to

  9. Estrategia Ambiental Provincial

    Angel A. Alfonso

    2010-10-01

    Full Text Available El trabajo que se presenta constituye la Estrategia Ambiental Provincial, elaborada por un Colectivo de Autores  formado por especialistas e investigadores de la Delegación Provincial del CITMA en Matanzas. Esta Estrategia ha sido onfeccionada según el marco de las orientaciones contenidas en la Estrategia Nacional y aborda los principales problemas medio ambientales presentados de forma jerárquica así como los instrumentos para la materialización de dicha Estrategia. El Resultado, primero de su tipo en el país, se elaboró con la aplicación de técnicas y métodos de la investigación científica, tales como: Método de Expertos, tormentas de ideas, método de los grupos nominales, método Delphi, método de votación directa o ponderada, Saaty etc. Los antecedentes principales que permitieron la obtención del Resultado fueron el Diagnóstico de la Situación Ambiental de la Provincia, las Estrategias Ambientales de las principales Empresas o Sectores de la Economía del territorio y los Diagnósticos de las Cuencas Hidrográficas. Se contó además con la colaboración de especialistas de otras instituciones provinciales tales como el Centro Provincial de Higiene y Epidemiología, Instituto de Recursos Hidráulicos, Empresa Nacional de Proyectos Agropecuarios del MINAGRI. El resultado fue constituído como política en el territorio en el mes de abril de 1998 con su aprobación por el Consejo de la Administración Provincial. 

  10. The Search for Non-Linear Exposure-Response Relationships at Ambient Levels in Environmental Epidemiology

    Lippmann, Morton

    2005-01-01

    Environmental exposures to ambient air particulate matter (PM), ozone (O3), environmental tobacco smoke (ETS), and to dioxin and related compounds are of considerable public health concern, and risk assessments for them have generally been based on linear, non-threshold models derived from epidemiological study data. While the epidemiological databases for PM, O3, and ETS have been sufficient to show that adverse health effects are occurring, the relative risks have been quite low, and it has...

  11. The Association of Ambient Air Pollution and Physical Inactivity in the United States

    Roberts, Jennifer D.; Voss, Jameson D.; Knight, Brandon

    2014-01-01

    Background Physical inactivity, ambient air pollution and obesity are modifiable risk factors for non-communicable diseases, with the first accounting for 10% of premature deaths worldwide. Although community level interventions may target each simultaneously, research on the relationship between these risk factors is lacking. Objectives After comparing spatial interpolation methods to determine the best predictor for particulate matter (PM2.5; PM10) and ozone (O3) exposures throughout the U....

  12. Short term respiratory health effects of ambient air pollution: results of the APHEA project in Paris.

    Dab, W; S. Medina; Quénel, P; Le Moullec, Y; Le Tertre, A; THELOT, B; Monteil, C; LAMELOISE,P; Pirard, P.; Momas, I; Ferry, R; Festy, B

    1996-01-01

    STUDY OBJECTIVE: To quantify the short term respiratory health effects of ambient air pollution in the Paris area. DESIGN: Time series analysis of daily pollution levels using Poisson regression. SETTING: Paris, 1987-92. MEASUREMENTS AND MAIN RESULTS: Air pollution was monitored by measurement of black smoke (BS) (15 monitoring stations), sulphur dioxide (SO2), nitrogen dioxide (NO2), particulate matter less than 13 microns in diameter (PM13), and ozone (O3) (4 stations). Daily mortality and ...

  13. Nitrogen oxides transport from La Cygne Station, KS: A study for assessing its influence on urban ozone. Final report

    As a result of the new ozone and PM 2.5 national ambient air quality standards, it appears that the Kansas City metropolitan area will be classified as nonattainment with respect to ozone. The Kansas Department of Health and Environment (KDHE) is planning to develop a new Kansas State Implementation Plan (SIP) to address this issue between 1997 and 2000 with implementation scheduled for 2004. Some Ozone Transport Assessment Group (OTAG) related air quality analyses have indicated that the Kansas City area is subject to surface and aloft windfields that could carry ozone or ozone precursors into Kansas City from outside the region, including from other parts of the state of Kansas. But questions have arisen whether or not local emission reductions would be more effective in achieving ozone standards. To better understand the causes of high ozone in the region and, specifically, to understand the role of emissions from certain power generating stations, the NOx Steering Committee was formed. The Committee includes representatives of the Kansas Department of Health and Environment and two local utility companies (Kansas City Power and Light (KCPL) and Western Resources). Input was also solicited from the US Environmental Protection Agency (EPA). This report presents the results of a scoping study commissioned by the Committee

  14. Suitability of Nicotiana tabacum 'Bel W3' for biomonitoring ozone in Sao Paulo, Brazil

    Sant' Anna, Silvia M.R.; Esposito, Marisia P.; Domingos, Marisa [Instituto de Botanica, Secao de Ecologia, Caixa Postal 3005, 01061-970 Sao Paulo, SP (Brazil); Souza, Silvia R. [Instituto de Botanica, Secao de Ecologia, Caixa Postal 3005, 01061-970 Sao Paulo, SP (Brazil)], E-mail: souzasrd@terra.com.br

    2008-01-15

    Nicotiana tabacum 'Bel W3' is a widely used sensitive bioindicator for ambient ozone, but it is rarely used in tropical countries. Our goal was to determine the suitability of this plant for biomonitoring ozone in the city of Sao Paulo by evaluating the relationships between leaf necroses and ozone under field conditions and measurements of chlorophyll a fluorescence and antioxidants in plants exposed to different concentrations of ozone in closed chambers. While a weak linear relationship between leaf injury and ozone concentrations (R{sup 2} = 0.10) was determined in the field, a strong linear relationship was observed in the chamber experiments. Maximum leaf injury was observed in plants submitted to 40 ppb, which coincided with a significant decrease in fluorescence and total ascorbic acid. The relationship between leaf damage observed in the field and ozone was improved when the concentrations were limited to 40 ppb (R{sup 2} = 0.28). - Nicotiana tabacum 'Bel W3' is suitable for indicating low ozone levels in Brazil.

  15. A network of autonomous surface ozone monitors in Antarctica: technical description and first results

    S. J.-B. Bauguitte

    2010-12-01

    Full Text Available A suite of 10 autonomous ozone monitors, each powered using renewable energy, was developed and built to study surface ozone in Antarctica during the International Polar Year (2007–2009. The monitoring systems were deployed in a network around the Weddell Sea sector of coastal Antarctica with a transect up onto the Antarctic Plateau. The aim was to measure for a full year, thus gaining a much-improved broader view of boundary layer ozone seasonality at different locations as well as of factors affecting the budget of surface ozone in Antarctica. Ozone mixing ratios were measured based on UV photometry using a modified version of the commercial 2B Technologies Inc. Model 202 instrument. All but one of the autonomous units measured successfully within its predefined duty cycle throughout the year, with some differences in performance dependent on power availability and ambient temperature. Mean data recovery after removal of outliers was on average 70% (range 44–83% and precision varied between 1.5 and 8 ppbv, thus was sufficiently good to resolve year-round the main ozone features of scientific interest. We conclude that, with adequate power, and noting a minor communication problem, our units would be able to operate successfully at ambient temperatures down to −60 °C. Systems such as the one described in this paper, or derivatives of it, could therefore be deployed either as local or regional networks elsewhere in the Arctic or Antarctic. Here we present technical information and first results from the experiment.

  16. A network of autonomous surface ozone monitors in Antarctica: technical description and first results

    S. J.-B. Bauguitte

    2011-04-01

    Full Text Available A suite of 10 autonomous ozone monitoring units, each powered using renewable energy, was developed and built to study surface ozone in Antarctica during the International Polar Year (2007–2009. The monitoring systems were deployed in a network around the Weddell Sea sector of coastal Antarctica with a transect up onto the Antarctic Plateau. The aim was to measure for a full year, thus gaining a much-improved broader view of boundary layer ozone seasonality at different locations as well as of factors affecting the budget of surface ozone in Antarctica. Ozone mixing ratios were measured based on UV photometry using a modified version of the commercial 2B Technologies Inc. Model 202 instrument. All but one of the autonomous units measured successfully within its predefined duty cycle throughout the year, with some differences in performance dependent on power availability and ambient temperature. Mean data recovery after removal of outliers was on average 70% (range 44–83% and precision varied between 1.5 and 8 ppbv, thus was sufficiently good to resolve year-round the main ozone features of scientific interest. We conclude that, with adequate power, and noting a minor communication problem, our units would be able to operate successfully at ambient temperatures down to −60 °C. Systems such as the one described in this paper, or derivatives of it, could therefore be deployed either as local or regional networks elsewhere in the Arctic or Antarctic. Here we present technical information and first results from the experiment.

  17. Mechanism of Fixation of Ozone and Its Medical Value

    ZHU Lei; MIN Xinmin; WANG Xuchao

    2014-01-01

    Because of both ozone gas and ozone solution are instable which limits the application of ozone, to solve the storage problem, it is necessary to find a kind of ideal ozone carrier which can combine ozone as an “ozonic compound” in which the bond strength between ozone and carrier should not be too high or too low, to appropriately release ozone from the ozonic compound. Combining Criegee’s three-step reaction mechanism of ozone and olefins, the charge, covalent bond levels and energy levels of ozone, ethylene, butadiene and their ozonic compounds were calculated by the first-principles calculation method based on density functional theory methods. The stability of the ozonide, or the bond strength between ozone and ions of carrier were controlled felicitously to release ozone from the ozonide with proper velocity. Ozone antimicrobial was composed on the above principle. It can be used conveniently, especially for common families.

  18. Ozone response to emission changes: a modeling study during the MCMA-2006/MILAGRO Campaign

    Song, J.; W. Lei; N. Bei; M. Zavala; De Foy, B.; Volkamer, R.; B. Cardenas; J. Zheng; Zhang, R; L. T. Molina

    2010-01-01

    The sensitivity of ozone production to precursor emissions was investigated under five different meteorological conditions in the Mexico City Metropolitan Area (MCMA) during the MCMA-2006/MILAGRO field campaign using the gridded photochemical model CAMx driven by observation-nudged WRF meteorology. Precursor emissions were constrained by the comprehensive data from the field campaign and the routine ambient air quality monitoring network. Simulated plume mixing and transport...

  19. Ozone response to emission changes: a modeling study during the MCMA-2006/MILAGRO Campaign

    Song, J.; Lei, W.; N. Bei; M. Zavala; de Foy, B.; R. Volkamer; Cardenas, B; Zheng, J.; Zhang, R.; L. T. Molina

    2010-01-01

    The sensitivity of ozone production to precursor emissions was investigated under five different meteorological conditions in the Mexico City Metropolitan Area (MCMA) during the MCMA-2006/MILAGRO field campaign using the gridded photochemical model CAMx driven by observation-nudged WRF meteorology. Precursor emissions were constrained by the comprehensive data from the field campaign and the routine ambient air quality monitoring network. Simulated plume mixing and transport were examined by ...

  20. [Ozone decline and UV increase].

    Winkler, P; Trepte, S

    2004-02-01

    The following results have been obtained from long-term observations on the ozone layer and UV at the Meteorological Observatory Hohenpeigenberg:The seasonally varying decline of the ozone layer determines the maximum exposure to UV. Since ozone decline shows the highest rates in the spring months the UV exposure has most strongly increased in this time of the year. This is especially important because in spring the human skin is not adapted to UV exposure. Weather changes from day to day can induce rapid ozone reductions in spring about -30% which in turn is followed by an increase in UV of about 40%. Clouds, especially the transparent cirrus clouds (high clouds consisting of ice particles) have increased in frequency during spring and fall while a decrease is observed in summer. This change in cloudiness reduces the daily UV dose in spring and fall while it is enhanced in summer. With increasing height above sea level UV rises by roughly 10% per 1000 m (rule of thumb). Snow reflects the UV-radiation by up to 80% enhancing the UV-doses at relevant conditions. Strong volcano eruptions destroy ozone in the stratosphere additionally during 1-2 years after the eruption. Therafter the ozone layer recovers. In April 1993, after the eruption of Mt. Pinatubo (1991), the UV burden was still 40% higher than average. Miniholes and streamers can appear unexpected on a short-time scale and cross over Central Europe within 1-2 days, thus enhancing UV irradiation. The human skin reacts to UV exposure depending on the type of skin. The campaign "Sonne(n) mit Verstand" of the Bavarian Ministries for Environment, for Health and for Education informs about the danger of UV radiation (see www.sonne-mit-ver-stand.de). The German Weather Service informs the public on present developments of the ozone layer and relevant topics byits ozone bulletin, which is also available via internet under (www.dwd.de/deFundE/Observator/MOHp/hp2/ozon/bulletin.htm). PMID:14770335