WorldWideScience

Sample records for ambient ozone growth

  1. Black cherry growth response to ambient ozone and EDU.

    Science.gov (United States)

    Long, R P; Davis, D D

    1991-01-01

    Field-grown black cherry (Prunus serotina Ehrh.) seedlings were treated with the antioxidant ethylenediurea (EDU) to evaluate height, diameter, and above-ground dry-weight biomass growth response to ambient ozone over four years. Nine blocks with 44 trees/block were used in a randomized complete block design with three foliar spray treatments: (1) 1000 ppm EDU mixed with a surfactant and water; (2) surfactant mixed with water; and (3) water only. In each growing season treatments were applied seven times at approximately 10-day intervals. Repeated measures analysis of variance indicated significant (P< or =0.05) treatment and year effects for log-transformed height and diameter growth over the four-year period. After four years, EDU-treated trees were approximately 17% taller and stem diameters were 21% greater than non-EDU-treated trees. Total above-ground dry-weight biomass at the end of four years was 47% greater for EDU-treated trees compared to non-EDU-treated trees. PMID:15092135

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

    Energy Technology Data Exchange (ETDEWEB)

    Manning, W.J. [Department of Microbiology, University of Massachusetts, 639 North Pleasant Street, Amherst, MA 01003-9298 (United States)]. E-mail: wmanning@microbio.umass.edu; Cooley, D.R. [Department of Microbiology, University of Massachusetts, 639 North Pleasant Street, Amherst, MA 01003-9298 (United States); Tuttle, A.F. [Department of Microbiology, University of Massachusetts, 639 North Pleasant Street, Amherst, MA 01003-9298 (United States); Frenkel, M.A. [Department of Microbiology, University of Massachusetts, 639 North Pleasant Street, Amherst, MA 01003-9298 (United States); Bergweiler, C.J. [Department of Microbiology, University of Massachusetts, 639 North Pleasant Street, Amherst, MA 01003-9298 (United States)

    2004-12-01

    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.

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

    International Nuclear Information System (INIS)

    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. Effects of ambient ozone on first-year growth and physiology of black cherry (Prunus serotina Ehrh. ) seedlings

    Energy Technology Data Exchange (ETDEWEB)

    Kolb, T.E.; Skelly, J.M.; Steiner, K.C.; Dunn, K. (Northern Arizona Univ., Flagstaff (United States) Pennsylvania State Univ., University Park (United States))

    1993-06-01

    Black cherry seedlings of two open-pollinated families were exposed to ambient ozone in open plots (100%) and plots receiving non-filtered (95%), half-filtered (60%) and full-filtered (40%) concentrations via open-top chambers between early June and late-September 1992 in a replicated field experiment in central Pennsylvania. Seasonal 24-hour ambient ozone concentration averaged 34 ppb with a peak 1-hour concentration of 110 ppb. Foliar symptoms of ozone damage (adaxial stipple) occurred most prominently in open and non-filtered plots and differed between families. Net photosynthetic rate for both families was significantly lower in open and non-filtered plots compared with half- and full-filtered plots on most dates, while ozone concentration had no consistent effect on leaf conductance or dark respiration. Leaf conductance of the ozone sensitive family was significantly greater than the ozone tolerant family on most dates. First-year height and diameter growth were significantly lower in open and non-filtered plots compared with half- and full-filtered plots for both families.

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

    International Nuclear Information System (INIS)

    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. INTERACTION OF SOIL MOISTURE STRESS AND AMBIENT OZONE ON GROWTH AND YIELDS OF SOYBEANS

    Science.gov (United States)

    A field experiment was conducted in open-top chambers to determine how interactions of soil moisture stress and exposure to ozone may affect soybean yields. Cultivars Williams and Forrest were grown in 1982 and Williams & Corsoy in 1983. Five levels of O3-including charcoal-filte...

  7. 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

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Poonam [Laboratory of Air Pollution and Global Climate Change, Ecology Research Circle, Department of Botany, Banaras Hindu University, Varanasi 221005 (India); Agrawal, Madhoolika [Laboratory of Air Pollution and Global Climate Change, Ecology Research Circle, Department of Botany, Banaras Hindu University, Varanasi 221005 (India)], E-mail: madhoo58@yahoo.com; Agrawal, Shashi Bhushan [Laboratory of Air Pollution and Global Climate Change, Ecology Research Circle, Department of Botany, Banaras Hindu University, Varanasi 221005 (India)

    2009-03-15

    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 O{sub 3} 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 O{sub 3}. - NPK level above recommended alleviates the adverse effects of ambient ozone on a tropical mustard cultivar.

  8. 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

    International Nuclear Information System (INIS)

    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

  9. 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)

    International Nuclear Information System (INIS)

    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

  10. Impact of ambient and elevated levels of ozone on growth, reproductive development and yield of two cultivars of rice ( Oryza sativa L.)

    International Nuclear Information System (INIS)

    Tow locally grown high yielding varieties of rice (Oryza sativa L. var Malviya dhan 36 and var shivani), were transplanted within the open top chambers (OTCs) at the age of 20 days. five different experimental plots were designed as open plot (OP), non-filtered chamber (NFCs), NFCs with 10 ppb ozone (O3), NFCs with 30 ppb O3 and filtered chamber (FCs) to assess the impact of ambient and elevated levels of O3 on rice. Twelve hourly monitoring of O3 and measurements of meteorological variables were done at experimental site during the growth period of rice plants. Morphological, reproductive, physico logical and biochemical parameters were assessed to evaluate the responses of rice cultivars to ambient and elevated levels of O3. (Author)

  11. Ethylenediurea (EDU) affects the growth of ozone-sensitive and tolerant ash (Fraxinus excelsior) trees under ambient O3 conditions.

    Science.gov (United States)

    Paoletti, Elena; Contran, Nicla; Manning, William J; Tagliaferro, Francesco

    2007-01-01

    Adult ash trees (Fraxinus excelsior L.), known to be sensitive or tolerant to ozone, determined by presence or absence of foliar symptoms in previous years, were treated with ethylenediurea (EDU) at 450 ppm by gravitational trunk infusion over the 2005 growing season (32.5 ppm h AOT40). Tree and shoot growth were recorded in May and September. Leaf area, ectomycorrhizal infection, and leaf and fine root biomass were determined in September. EDU enhanced shoot length and diameter, and the number and area of leaves, in both O3-sensitive and tolerant trees. However, no EDU effects were recorded at the fine root and tree level. Therefore, a potential for EDU protection against O3-caused growth losses of forest trees should be evaluated during longer-term experiments. PMID:17450289

  12. Sensitivity of four hardwood species to ambient ozone in north central Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    Simini, M.; Skelly, J.M.; Davis, D.D.; Savage, J.E.; Comrie, A.C. (Pennsylvania State Univ., Pennsylvania Park, PA (United States))

    1992-01-01

    Studies were performed to determine the injury growth response of four native species to ambient ozone on three ridgetop sites of the Allegheny Plateau of north central Pennsylvania. Open-top chambers were established at each site and seedlings of black cherry (Prunus serotina Ehrh.), yellow poplar (Liriodendron tulipifera L.), red oak (Quercus rubra L.), and red maple (Acer rubrum L.) were exposed to ambient air or to charcoal filtered air containing approximately 95, 60 or 40% of ambient ozone in randomized, complete blocks in 1988 and 1989. Black cherry seedlings were also exposed in 1990. Ozone was greatest in 1988 at all sites, and total ozone during the 3-year study was greatest at the westernmost sites. Foliar stipple injury of black cherry and yellow poplar were correlated positively with ozone within and among sites throughout the study. Premature leaf abscission of both species was significantly greater with higher ozone levels at one site in 1988 and 1989. Ozone stipple was not observed on red maple and red oak seedlings. Ambient ozone did not significantly decrease height, basal diameter, or leaf surface area of any species. Possible explanations for temporal and spatial ozone variation and subsequent plant response are discussed. 36 refs., 5 figs., 7 tabs.

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

    International Nuclear Information System (INIS)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Manning, W.J.; Godzik, B

    2004-07-01

    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.

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

    International Nuclear Information System (INIS)

    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

  17. Association between ambient ozone and health outcomes in Prague.

    Czech Academy of Sciences Publication Activity Database

    H?nová, I.; Malý, Marek; ?ezá?ová, J.; Braniš, M.

    2013-01-01

    Ro?. 86, ?. 1 (2013), s. 89-97. ISSN 0340-0131 Grant ostatní: GA MŠk(CZ) 2B08077; GA AV ?R(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

  18. 40 CFR 50.15 - National primary and secondary ambient air quality standards for ozone.

    Science.gov (United States)

    2010-07-01

    ... air quality standards for ozone. 50.15 Section 50.15 Protection of Environment ENVIRONMENTAL....15 National 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 (O3) is 0.075 parts...

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

    Science.gov (United States)

    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

  20. Development of KRISS standard reference photometer (SRP) for ambient ozone measurement

    Science.gov (United States)

    Lee, S.; Lee, J.

    2014-12-01

    Surface ozone has adverse impacts on human health and ecosystem. Accurate measurement of ambient ozone concentration is essential for developing effective mitigation strategies and understanding atmospheric chemistry. Korea Research Institute of Standards and Science (KRISS) has developed new ozone standard reference photometers (SRPs) for the calibration of ambient ozone instruments. The basic principle of the KRISS ozone SRPs is to determine the absorption of ultraviolet radiation at a specific wavelength, 253.7 nm, by ozone in the atmosphere. Ozone concentration is calculated by converting UV transmittance through the Beer-Lambert Law. This study introduces the newly developed ozone SRPs and characterizes their performance through uncertainty analysis and comparison with BIPM (International Bureau of Weights and Measures) SRP.

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

    International Nuclear Information System (INIS)

    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

  2. 40 CFR 50.10 - National 8-hour primary and secondary ambient air quality standards for ozone.

    Science.gov (United States)

    2010-07-01

    ... ambient air quality standards for ozone. 50.10 Section 50.10 Protection of Environment ENVIRONMENTAL....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...

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

    Science.gov (United States)

    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.

  4. 78 FR 34177 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: State Implementation...

    Science.gov (United States)

    2013-06-06

    ...updates to the modeling guidance are needed to address modeling of the HEDD phenomenon...ambient ozone data and modeled ozone...recent monitored values by the modeled...and above, the modeling and other elements...exclude monitoring data influenced by...classified as Severe or Extreme, the...

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

    Science.gov (United States)

    Yuan, Xiangyang; Calatayud, Vicent; Jiang, Lijun; Manning, William J; Hayes, Felicity; Tian, Yuan; Feng, Zhaozhong

    2015-10-01

    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 8h (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. PMID:26074161

  6. A Statistical Modeling Framework for Projecting Future Ambient Ozone and its Health Impact due to Climate Change

    OpenAIRE

    Chang, Howard H.; Hao, Hua; Sarnat, Stefanie Ebelt

    2014-01-01

    The adverse health effects of ambient ozone are well established. Given the high sensitivity of ambient ozone concentrations to meteorological conditions, the impacts of future climate change on ozone concentrations and its associated health effects are of concern. We describe a statistical modeling framework for projecting future ozone levels and its health impacts under a changing climate. This is motivated by the continual effort to evaluate projection uncertainties to inform public health...

  7. Highly sensitive and selective bioluminescence based ozone probes and their applications to detect ambient ozone.

    Science.gov (United States)

    Nam, Younseok; Kim, Beom Seok; Shin, Injae

    2016-01-01

    Highly selective and sensitive bioluminescence based probes, which respond to ozone but not to other ROS, have been developed. These probes were used to determine ozone concentrations in environmental samples. PMID:26567538

  8. Which metric of ambient ozone to predict daily mortality?

    Science.gov (United States)

    Moshammer, Hanns; Hutter, Hans-Peter; Kundi, Michael

    2013-02-01

    It is well known that ozone concentration is associated with daily cause specific mortality. But which ozone metric is the best predictor of the daily variability in mortality? We performed a time series analysis on daily deaths (all causes, respiratory and cardiovascular causes as well as death in elderly 65+) in Vienna for the years 1991-2009. We controlled for seasonal and long term trend, day of the week, temperature and humidity using the same basic model for all pollutant metrics. We found model fit was best for same day variability of ozone concentration (calculated as the difference between daily hourly maximum and minimum) and hourly maximum. Of these the variability displayed a more linear dose-response function. Maximum 8 h moving average and daily mean value performed not so well. Nitrogen dioxide (daily mean) in comparison performed better when previous day values were assessed. Same day ozone and previous day nitrogen dioxide effect estimates did not confound each other. Variability in daily ozone levels or peak ozone levels seem to be a better proxy of a complex reactive secondary pollutant mixture than daily average ozone levels in the Middle European setting. If this finding is confirmed this would have implications for the setting of legally binding limit values.

  9. Colorimetric determination of ambient ozone using indigo blue droplet

    OpenAIRE

    Felix Erika P.; Cardoso Arnaldo A.

    2006-01-01

    A simple and sensitive method based on a liquid droplet is described for the measurement of atmospheric ozone. A 30 µL drop of indigo blue solution is suspended in a flowing-air sampling stream. The ozone collected reacts with the indigo solution resulting in its decolorization. The colorimetric sensor is composed of two optical fibers and the source of monochromatic light was a red LED (625 nm). The calibration curve was constructed with ozone standard concentrations ranging from 37 - 123 pp...

  10. Constraining ozone-precursor responsiveness using ambient measurements

    Science.gov (United States)

    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...

  11. International Comparison CCQM-P28: Ozone at Ambient Level

    OpenAIRE

    VIALLON Joële; MOUSSAY Philippe; ESLER Michael; WIELGOSZ Robert; BREMSER Wolfram; Novák, Ji?í; VOKOUN Miroslav; BOTHA Angelique; VAN RENSBURG Mellisa Janse; Zellweger, Christoph; GOLDTHORP Sandra; BOROWIAK ANNETTE; LAGLER FRIEDRICH; Walden, Jari; MALGERI Ettore

    2006-01-01

    We report a pilot study organized within the Consultative Committee for Amount of Substance (CCQM), in which the ozone reference standards of 23 institutes have been compared to one common reference, the BIPM ozone reference standard, in a series of bilateral comparisons carried out between July 2003 and February 2005. The BIPM, which maintains as its reference standard a standard reference photometer (SRP) developed by the National Institute of Standards and Technology (NIST, United States),...

  12. Use of bioindicators and passive sampling devices to evaluate ambient ozone concentrations in north central Pennsylvania

    International Nuclear Information System (INIS)

    Passive samplers and bioindicator plants detect ozone air pollution in north central Pennsylvania. - Ambient concentrations of tropospheric ozone and ozone-induced injury to black cherry (Prunus serotina) and common milkweed (Asclepias syriaca) were determined in north central Pennsylvania from 29 May to 5 September 2000 and from 28 May to 18 September 2001. Ogawa passive ozone samplers were utilized within openings at 15 forested sites of which six were co-located with TECO model 49 continuous ozone monitors. A significant positive correlation was observed between the Ogawa passive samplers and the TECO model 49 continuous ozone monitors for the 2000 (r=0.959) and 2001 (r=0.979) seasons. In addition, a significant positive correlation existed in 2000 and 2001 between ozone concentration and elevation (r=0.720) and (r=0.802), respectively. Classic ozone-induced symptoms were observed on black cherry and common milkweed. In 2000, initial injury was observed in early June, whereas for the 2001 season, initial injury was initially observed in late June. During both seasons, injury was noted at most sites by mid- to late-July. Soil moisture potential was measured for the 2001 season and a significant positive relationship (P<0.001) showed that injury to black cherry was a function of cumulative ozone concentrations and available soil moisture

  13. Use of bioindicators and passive sampling devices to evaluate ambient ozone concentrations in north central Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    Yuska, D.E.; Skelly, J.M.; Ferdinand, J.A.; Stevenson, R.E.; Savage, J.E.; Mulik, J.D.; Hines, A

    2003-09-01

    Passive samplers and bioindicator plants detect ozone air pollution in north central Pennsylvania. - Ambient concentrations of tropospheric ozone and ozone-induced injury to black cherry (Prunus serotina) and common milkweed (Asclepias syriaca) were determined in north central Pennsylvania from 29 May to 5 September 2000 and from 28 May to 18 September 2001. Ogawa passive ozone samplers were utilized within openings at 15 forested sites of which six were co-located with TECO model 49 continuous ozone monitors. A significant positive correlation was observed between the Ogawa passive samplers and the TECO model 49 continuous ozone monitors for the 2000 (r=0.959) and 2001 (r=0.979) seasons. In addition, a significant positive correlation existed in 2000 and 2001 between ozone concentration and elevation (r=0.720) and (r=0.802), respectively. Classic ozone-induced symptoms were observed on black cherry and common milkweed. In 2000, initial injury was observed in early June, whereas for the 2001 season, initial injury was initially observed in late June. During both seasons, injury was noted at most sites by mid- to late-July. Soil moisture potential was measured for the 2001 season and a significant positive relationship (P<0.001) showed that injury to black cherry was a function of cumulative ozone concentrations and available soil moisture.

  14. Colorimetric determination of ambient ozone using indigo blue droplet

    Directory of Open Access Journals (Sweden)

    Felix Erika P.

    2006-01-01

    Full Text Available A simple and sensitive method based on a liquid droplet is described for the measurement of atmospheric ozone. A 30 µL drop of indigo blue solution is suspended in a flowing-air sampling stream. The ozone collected reacts with the indigo solution resulting in its decolorization. The colorimetric sensor is composed of two optical fibers and the source of monochromatic light was a red LED (625 nm. The calibration curve was constructed with ozone standard concentrations ranging from 37 - 123 ppbv. The detection limit achieved was 7.3 ppbv. The method considered here showed itself to be easy to apply with a fast response and a total analysis time of only 5 minutes.

  15. 40 CFR 50.9 - National 1-hour primary and secondary ambient air quality standards for ozone.

    Science.gov (United States)

    2010-07-01

    ...-hour standards are codified in 40 CFR part 81. (c) EPA's authority under paragraph (b) of this section... ambient air quality standards for ozone. 50.9 Section 50.9 Protection of Environment ENVIRONMENTAL....9 National 1-hour primary and secondary ambient air quality standards for ozone. (a) The level...

  16. Use of bioindicators and passive sampling devices to evaluate ambient ozone concentrations in north central Pennsylvania.

    Science.gov (United States)

    Yuska, D E; Skelly, J M; Ferdinand, J A; Stevenson, R E; Savage, J E; Mulik, J D; Hines, A

    2003-01-01

    Ambient concentrations of tropospheric ozone and ozone-induced injury to black cherry (Prunus serotina) and common milkweed (Asclepias syriaca) were determined in north central Pennsylvania from 29 May to 5 September 2000 and from 28 May to 18 September 2001. Ogawa passive ozone samplers were utilized within openings at 15 forested sites of which six were co-located with TECO model 49 continuous ozone monitors. A significant positive correlation was observed between the Ogawa passive samplers and the TECO model 49 continuous ozone monitors for the 2000 (r=0.959) and 2001 (r=0.979) seasons. In addition, a significant positive correlation existed in 2000 and 2001 between ozone concentration and elevation (r=0.720) and (r=0.802), respectively. Classic ozone-induced symptoms were observed on black cherry and common milkweed. In 2000, initial injury was observed in early June, whereas for the 2001 season, initial injury was initially observed in late June. During both seasons, injury was noted at most sites by mid- to late-July. Soil moisture potential was measured for the 2001 season and a significant positive relationship (P<0.001) showed that injury to black cherry was a function of cumulative ozone concentrations and available soil moisture. PMID:12804829

  17. Modeling the effects of ozone on soybean growth and yield.

    Science.gov (United States)

    Kobayashi, K; Miller, J E; Flagler, R B; Heck, W W

    1990-01-01

    A simple mechanistic model was developed based on an existing growth model in order to address the mechanisms of the effects of ozone on growth and yield of soybean [Glycine max. (L.) Merr. 'Davis'] and interacting effects of other environmental stresses. The model simulates daily growth of soybean plants using environmental data including shortwave radiation, temperature, precipitation, irrigation and ozone concentration. Leaf growth, dry matter accumulation, water budget, nitrogen input and seed growth linked to senescence and abscission of leaves are described in the model. The effects of ozone are modeled as reduced photosynthate production and accelerated senescence. The model was applied to the open-top chamber experiments in which soybean plants were exposed to ozone under two levels of soil moisture regimes. After calibrating the model to the growth data and seed yield, goodness-of-fit of the model was tested. The model fitted well for top dry weight in the vegetative growth phase and also at maturity. The effect of ozone on seen yield was also described satisfactorily by the model. The simulation showed apparent interaction between the effect of ozone and soil moisture stress on the seed yield. The model revealed that further work is needed concerning the effect of ozone on the senescence process and the consequences of alteration of canopy microclimate by the open-top chambers. PMID:15092277

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

    Science.gov (United States)

    Novak, Kristopher; Cherubini, Paolo; Saurer, Matthias; Fuhrer, Jürg; Skelly, John M; Kräuchi, Norbert; Schaub, Marcus

    2007-07-01

    We assessed the effects of ambient tropospheric ozone on annual tree-ring growth, delta(13)C in the rings, leaf gas exchange and visible injury in three ozone-sensitive woody plant species in southern Switzerland. Seedlings of Populus nigra L., Viburnum lantana L. and Fraxinus excelsior L. were exposed to charcoal-filtered air (CF) and non-filtered air (NF) in open-top chambers, and to ambient air (AA) in open plots during the 2001 and 2002 growing seasons. Ambient ozone exposures in the region were sufficient to cause visible foliar injury, early leaf senescence and premature leaf loss in all species. Ozone had significant 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 CO(2) concentrations increased in all species in response to ozone in 2002 only. The width and delta(13)C of the 2001 and 2002 growth rings were measured for all species at the end of the 2002 growing season. Compared with CF seedlings, mean ring width in the AA and NF P. nigra seedlings was reduced by 52 and 46%, respectively, in 2002, whereas in V. lantana and F. excelsior, ring width showed no significant reductions in either year. Although delta(13)C was usually more negative in CF seedlings than in AA and NF seedlings, with the exception of F. excelsior in 2001, ozone effects on delta(13)C were significant only for V. lantana and P. nigra in 2001. Among species, P. nigra exhibited the greatest response to ozone for the measured parameters as well as the most severe foliar injury and was the only species to show a significant reduction in ring width in response to ozone exposure, despite significant negative ozone effects on leaf gas exchange and the development of visible foliar injury in V. lantana and F. excelsior. Thus, significant ozone-induced effects at the leaf level did not correspond to reduced tree-ring growth or increased delta(13)C in all species, indicating that the timing of ozone exposure and severity of leaf-level responses may be important in determining the sensitivity of tree productivity to ozone exposure. PMID:17403646

  19. 77 FR 30087 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards

    Science.gov (United States)

    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...

  20. Tree and stand growth of mature Norway spruce and European beech under long-term ozone fumigation

    Energy Technology Data Exchange (ETDEWEB)

    Pretzsch, Hans, E-mail: h.pretzsch@lrz.tum.d [Chair for Forest Growth and Yield Science, Technische Universitaet Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Dieler, Jochen [Chair for Forest Growth and Yield Science, Technische Universitaet Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Matyssek, Rainer [Chair for Ecophysiology of Plants, Technische Universitaet Muenchen, Am Hochanger 13, D-85354 Freising (Germany); Wipfler, Philip [Chair for Forest Growth and Yield Science, Technische Universitaet Muenchen, Am Hochanger 13, D-85354 Freising (Germany)

    2010-04-15

    In a 50- to 70-year-old mixed stand of Norway spruce (Picea abies (L.) Karst.) and European beech (Fagus sylvatica L.) in Germany, tree cohorts have been exposed to double ambient ozone (2xO{sub 3}) from 2000 through 2007 and can be compared with trees in the same stand under the ambient ozone regime (1xO{sub 3}). Annual diameter growth, allocation pattern, stem form, and stem volume were quantified at the individual tree and stand level. Ozone fumigation induced a shift in the resource allocation into height growth at the expense of diameter growth. This change in allometry leads to rather cone-shaped stem forms and reduced stem stability in the case of spruce, and even neiloidal stem shapes in the case of beech. Neglect of such ozone-induced changes in stem shape may lead to a flawed estimation of volume growth. On the stand level, 2xO{sub 3} caused, on average, a decrease of 10.2 m{sup 3} ha{sup -1} yr{sup -1} in European beech. - Ozone effects on tree growth and stem shape were investigated for Norway spruce and European beech; the study reveals species-specific reaction patterns in growth rate and allometry under ozone exposure.

  1. Tree and stand growth of mature Norway spruce and European beech under long-term ozone fumigation

    International Nuclear Information System (INIS)

    In a 50- to 70-year-old mixed stand of Norway spruce (Picea abies (L.) Karst.) and European beech (Fagus sylvatica L.) in Germany, tree cohorts have been exposed to double ambient ozone (2xO3) from 2000 through 2007 and can be compared with trees in the same stand under the ambient ozone regime (1xO3). Annual diameter growth, allocation pattern, stem form, and stem volume were quantified at the individual tree and stand level. Ozone fumigation induced a shift in the resource allocation into height growth at the expense of diameter growth. This change in allometry leads to rather cone-shaped stem forms and reduced stem stability in the case of spruce, and even neiloidal stem shapes in the case of beech. Neglect of such ozone-induced changes in stem shape may lead to a flawed estimation of volume growth. On the stand level, 2xO3 caused, on average, a decrease of 10.2 m3 ha-1 yr-1 in European beech. - Ozone effects on tree growth and stem shape were investigated for Norway spruce and European beech; the study reveals species-specific reaction patterns in growth rate and allometry under ozone exposure.

  2. Colorimetric determination of ambient ozone using indigo blue droplet

    Scientific Electronic Library Online (English)

    Erika P., Felix; Arnaldo A., Cardoso.

    2006-04-01

    Full Text Available Um método simples e sensível, baseado em uma gota líquida, é descrito para medida do ozônio atmosférico. Uma gota de 30 µL de solução de índigo azul é suspensa em uma corrente de ar para amostragem. O ozônio coletado reage com a solução de índigo azul, provocando seu descoramento. O sensor colorimét [...] rico é composto por duas fibras ópticas; a fonte de luz monocromática usada foi um LED vermelho (625 nm). A curva analítica foi construída com concentrações padrão de ozônio, na faixa de 37 a 123 ppbv. O limite de detecção alcançado foi 7,3 ppbv. O método considerado mostrou-se de fácil aplicação e resposta rápida, com um tempo total de análise de apenas 5 minutos. Abstract in english A simple and sensitive method based on a liquid droplet is described for the measurement of atmospheric ozone. A 30 µL drop of indigo blue solution is suspended in a flowing-air sampling stream. The ozone collected reacts with the indigo solution resulting in its decolorization. The colorimetric sen [...] sor is composed of two optical fibers and the source of monochromatic light was a red LED (625 nm). The calibration curve was constructed with ozone standard concentrations ranging from 37 - 123 ppbv. The detection limit achieved was 7.3 ppbv. The method considered here showed itself to be easy to apply with a fast response and a total analysis time of only 5 minutes.

  3. Response of different-aged black cherry trees to ambient ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Fredericksen, T.S.; Joyce, B.J.; Kouterick, K.B.; Kolb, T.E.; Skelly, J.M.; Steiner, K.C.; Savage, J.E.; Snyder, K.R. (Pennyslvania State Univ., Univ. Park, PA (United States))

    1994-06-01

    Black cherry (Prunus serotina Ehrh.) is a valuable commercial timber species which is also highly sensitive to ozone relative to other eastern deciduous tree species. Studies of ozone effects on forest trees have been restricted mostly to experiments using small seedlings under controlled conditions. Yet, mature trees may differ from seedlings in physiology, morphology, and exposure to air pollutants. An experiment was conducted in 1993 to determine differences in ozone uptake and foliar injury symptoms between open-ground seedlings, forest saplings, and mature forest trees of black cherry in northcentral Pennsylvania. Seedlings grew under the highest ozone concentrations and also had greater seasonal ozone uptake due to higher rates of stomatal conductance. However, because of their indeterminate growth habit, seedlings had lower cumulative ozone uptake per leaf lifespan than saplings or mature trees, both of which had determinate shoot growth. Although greater initially for seedlings, foliar injury was nearly identical between size classes by the end of the growing season. Leaves in the lower crown of larger trees had lower ozone uptake than leaves in the upper crown, but exhibited more foliar injury symptoms. Lower crown leaves received more effective exposure to ozone because of their thinner leaves and had less available photosynthate for repair or replacement of damaged tissue.

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Modeling the effects of reformulated gasoline usages on ambient concentrations of ozone and five air toxics

    International Nuclear Information System (INIS)

    The use of reformulated gasolines to reduce motor-vehicle-related hydrocarbon emissions has been mandated by the 1990 Clean Air Act Amendments for nine severely polluted urban areas. Using a version of the Urban Airshed Model that includes explicit representation of five motor-vehicle-related air toxics, the effects of reformulated gasoline usage on ambient ozone and toxics concentrations were simulated. Simulations were conducted for two urban areas. Baltimore-Washington and Houston, for the year 1995. Additional simulation were conducted for Baltimore-Washington including winter and 1999 scenarios. In the Baltimore-Washington areas, the 1995 Federal reformulated gasoline scenario produce reductions of 1.1 percent in simulated peak ozone and 2.7 percent in the areal extent of simulated ozone exceedances. Simulated ozone reductions were much smaller in Houston. In the reformulated gasoline simulations, secondary formulation of formaldehyde and acetaldehyde was reduced, and decreases in ambient benzene and polycyclic organic matter (POM) concentrations were simulated. Larger reductions in ozone and toxics concentrations were simulated for reformulated gasolines meeting California Phase II standards than for those meeting Federal standards. The effects of reductions in motor-vehicle-related nitrogen oxides (NOx) emissions, alone and in combination with hydrocarbon reductions, were also examined

  6. Relationship between summertime ambient ozone levels and emergency department visits for asthma in central New Jersey

    Energy Technology Data Exchange (ETDEWEB)

    Weisel, C.P.; Cody, R.P.; Lioy, P.J. [Rutgers Univ., Piscataway, NJ (United States)

    1995-03-01

    The 5-year retrospective study of the association between temperature and emergency department (ED) visits for asthma with mean ambient ozone levels between 10:00 and 15:00 was conducted in central New Jersey during the summer months. An association was identified in each of the years (1986-1990). Between 8 and 34% of the total variance in ED visits for asthma was explained by the two environmental variables in the step-wise multiple regression analysis. ED visits occurred 28% more frequently when the mean ozone levels were >0.06 ppm than when they were < 0.06 ppm. This result was statistically significant in a covariance analysis. An evaluation of the effects of ozone on asthmatics reported in the literature was completed to determine if, as proposed by Bates, the results from different types of studies were coherent among the health metrics. A consistency in the magnitude of reported effects and the time lag between exposure and response for four different health indices (symptom reports, decrements in expiratory flow, ED visits, and hospital admissions) was identified and indicates a coherence between ozone and respiratory response to ozone exposure. This supports a proposition that ozone adversely affects asthmatics at levels below the current U.S. standard. 34 refs., 1 fig., 4 tabs.

  7. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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

  9. 77 FR 34221 - Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards for Several...

    Science.gov (United States)

    2012-06-11

    ...FRL 9682-2] RIN 2060-AR56 Air Quality Designations for the 2008 Ozone National Ambient Air Quality Standards for Several Counties...This rule completes the initial air quality designations for the 2008...

  10. Short-term exposure to ambient ozone and stroke hospital admission: A case-crossover analysis.

    Science.gov (United States)

    Montresor-López, Jessica A; Yanosky, Jeff D; Mittleman, Murray A; Sapkota, Amir; He, Xin; Hibbert, James D; Wirth, Michael D; Puett, Robin C

    2016-03-01

    We evaluated the association between short-term exposure to ambient ozone air pollution and stroke hospital admissions among adult residents of South Carolina (SC). Data on all incident stroke hospitalizations from 2002 to 2006 were obtained from the SC Office of Research and Statistics. Ozone exposure data were obtained from the US Environmental Protection Agency's Hierarchical Bayesian Model. A semi-symmetric bidirectional case-crossover design was used to examine the association between ozone exposure on lag days 0-2 (0 to 2 days before admission) and stroke hospitalization. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). No significant associations were observed between short-term ozone exposure and hospitalization for all stroke (e.g., lag day 0: OR=0.98; 95% CI=0.96, 1.00) or ischemic stroke (lag day 0: OR=0.98; 95% CI=0.96, 1.01). Risk of hospitalization for hemorrhagic stroke appeared to be higher among African Americans than European Americans; however, the majority of these associations did not reach statistical significance. Among adults in SC from 2002 to 2006, there was no evidence of an association between ozone exposure and risk of hospitalization for all stroke or ischemic stroke; however, African Americans may have an increased risk of hemorrhagic stroke. PMID:26329139

  11. Interference of ozone with measurements of particle bound benzo[a]pyrene in ambient air; Ozon-Querempfindlichkeit bei der Immissionsmessung von schwebstaubakkumuliertem Benzo[a]pyren

    Energy Technology Data Exchange (ETDEWEB)

    Creutznacher, H. [UMEG Zentrum fuer Umweltmessungen, Umwelterhebungen und Geraetesicherheit, Baden-Wuerttemberg, Karlsruhe (Germany); Huber, K. [Fachhochschule Offenburg (Germany)

    2002-08-01

    When the load of particle bound polycyclic (PAH) in ambient air is to be assessed, usually benzo[a]pyrene (BaP) is measured as an indicator substance. Since the European Commission is about to establish a limit value for BaP (most likely for the yearly average) a CEN working group was installed to develop a European Standard for the determination of BaP in ambient air. It is known from literature that during sampling of ambient air, BaP degradation may occur, if reactive gases like ozone or nitrogen dioxide are present. A sampling device for the determination of various particle bound air pollutants was developed. With this sampling device it is possible to sample PAH while removing e. g. ozone by using a so called ozone scrubber. Thus it is possible for the first time to study degradation effects or reactions of BaP or other PAH with ozone. After laboratory experiments proved the effectiveness of the ozone scrubber, experiments in ambient air were carried out. The goal of this study was to get quantitative data on the extent of BaP degradation during measurements in ambient air. An experimental set-up was chosen, which allowed to feed in various ozone concentrations at the suction inlet of the sampling cartridge. The results of the study proved that there is a significant degradation of BaP through ozone during the sampling. This interference can be avoided by using the ozone scrubber in the new sampling device. (orig.)

  12. On-line monitoring of ambient NMHC Ozone Precursors. The French Experience

    Energy Technology Data Exchange (ETDEWEB)

    Locoge, N. [Departement Chimie et Environnement, Ecole des Mines de Douai, Douai (France)

    2004-07-01

    Non-methane hydrocarbons (NMHC) with up to 10 carbon atom number form the main part of volatile organic compounds (VOC) in urban areas. They play an important role in urban air quality since among these compounds some of them like benzene and 1,3- butadiene are proven carcinogens. Moreover, NMHC play an important role in the photochemical mechanism leading to the formation of excess ozone and other oxidants in the troposphere. This paper presents the French experience in the on-line monitoring of NMHC Ozone Precursors focused on the thirty-one VOC whose concentrations are recommended for measurement in the European directive relating to ozone in ambient air (EC 2002/3/CE directive). Concerning the BTEX compounds and more precisely the benzene which is the only one reglemented compound a brief presentation of the automatic French equipment will be made. Concerning the on-line monitoring, the implementation of automated monitoring systems was made in France step by step from the development of the equipment (on-line sampling with GC-FID analysis of the C2-C9 NMHC priority list) at the 'Ecole des Mines de Douai' (EMD, France) with emphasis on sampling optimisation and calibration method to the field implementation of the automated system at urban locations in northern France with the parallel development of a routine Quality Control (QC) procedure. This work was supported supported by the LCSQA (French Central Laboratory of Air Quality Monitoring). The four-year-successful routine experiences have indicated the suitability of the system for long periods (operating ratio: 88%). Finally, although there is no legal requirements concerning the monitoring of ozone precursors, the on-line measuring equipment was extended to four of the French Air Quality Monitoring Networks in 2001 through a national programme devoted to the monitoring of ozone precursors in ambient air and initiated by the French Ministry of Environment.

  13. Long-term ambient ozone concentration and the incidence of asthma in nonsmoking adults: The Ahsmog study

    Energy Technology Data Exchange (ETDEWEB)

    McDonnell, W.F. [Environmental Protection Agency, Research Triangle Park, NC (United States). National Health and Environmental Effects Research Lab.; Abbey, D.E.; Nishino, N. [Loma Linda Univ., CA (United States). School of Public Health; Lebowitz, M.D. [Univ. of Arizona Coll. of Medicine, Tucson, AZ (United States).

    1999-02-01

    The authors conducted a prospective study of a cohort of 3091 nonsmokers, ages 27 to 87 years, to evaluate the association between long-term ambient ozone exposure and development of adult-onset asthma. Over a 15-year period, 3.2% of males and 4.3% of females reported new doctor diagnoses of asthma. For males, they observed a significant relationship between report of doctor diagnosis of asthma and 20-year mean 8-h average ambient ozone concentration. The authors observed no such relationship for females. Other variables significantly related to development of asthma were a history of ever-smoking for males, and for females, number of years worked with a smoker, age, and a history of childhood pneumonia or bronchitis. Addition of other pollutants to the models did not diminish the relationship between ozone and asthma for males. These data suggest that long-term exposure to ambient ozone is associated with development of asthma in adult males.

  14. Tree and stand growth of mature Norway spruce and European beech under long-term ozone fumigation.

    Science.gov (United States)

    Pretzsch, Hans; Dieler, Jochen; Matyssek, Rainer; Wipfler, Philip

    2010-04-01

    In a 50- to 70-year-old mixed stand of Norway spruce (Picea abies (L.) Karst.) and European beech (Fagus sylvatica L.) in Germany, tree cohorts have been exposed to double ambient ozone (2xO(3)) from 2000 through 2007 and can be compared with trees in the same stand under the ambient ozone regime (1xO(3)). Annual diameter growth, allocation pattern, stem form, and stem volume were quantified at the individual tree and stand level. Ozone fumigation induced a shift in the resource allocation into height growth at the expense of diameter growth. This change in allometry leads to rather cone-shaped stem forms and reduced stem stability in the case of spruce, and even neiloidal stem shapes in the case of beech. Neglect of such ozone-induced changes in stem shape may lead to a flawed estimation of volume growth. On the stand level, 2xO(3) caused, on average, a decrease of 10.2 m(3) ha(-1) yr(-1) in European beech. PMID:19713019

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

    International Nuclear Information System (INIS)

    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)

  16. Exposure-plant response of ambient ozone over the tropical Indian region

    Directory of Open Access Journals (Sweden)

    S. Roy

    2009-02-01

    Full Text Available A high resolution regional chemistry-transport model has been used to study the distribution of exposure-plant response index (AOT40, Accumulated exposure Over a Threshold of 40 ppb, expressed as ppb h over the Indian geographical region for the year 2003 as case study. The directives on ozone pollution in ambient air provided by United Nations Economic Commission for Europe (UNECE and World Health Organization (WHO for vegetation protection (AOT40 have been used to assess the air quality. A substantial temporal and spatial variation in AOT40 values has been observed across the Indian region. Large areas of India show ozone values above the AOT40 threshold limit (3000 ppb h for 3 months. Simulated AOT40 values are found to be substantially higher throughout the year over the most fertile Indo-Gangetic plains than the other regions of India, which can have an adverse effect on plants and vegetation in this region. The observed monthly AOT40 values reported from an Indian station, agree reasonably well with model simulated results. We find that the simulated AOT40 target values for protection of vegetation is exceeded even in individual months, especially during November and April. Necessary and effective emission reduction strategies are therefore required to be developed in order to curb the surface level ozone pollution to protect the vegetation from further damage in India whose economy is highly dependent on agricultural sector and may influence the global balance.

  17. Exposure-plant response of ambient ozone over the tropical Indian region

    Directory of Open Access Journals (Sweden)

    S. Deb Roy

    2009-07-01

    Full Text Available A high resolution regional chemistry-transport model has been used to study the distribution of exposure-plant response index (AOT40, Accumulated exposure Over a Threshold of 40 ppb, expressed as ppb h over the Indian geographical region for the year 2003 as case study. The directives on ozone pollution in ambient air provided by United Nations Economic Commission for Europe (UNECE and World Health Organization (WHO for vegetation protection (AOT40 have been used to assess the air quality. A substantial temporal and spatial variation in AOT40 values has been observed across the Indian region. Large areas of India show ozone values above the AOT40 threshold limit (3000 ppb h for 3 months. Simulated AOT40 values are found to be substantially higher throughout the year over the most fertile Indo-Gangetic plains than the other regions of India, which can have an adverse effect on plants and vegetation in this region. The observed monthly AOT40 values reported from an Indian station, agree reasonably well with model simulated results. There is an underestimation of AOT40 in the model results during the periods of highest ozone concentration from December to March. We find that the simulated AOT40 target values for protection of vegetation is exceeded even in individual months, especially during November to April. Necessary and effective emission reduction strategies are therefore required to be developed in order to curb the surface level ozone pollution to protect the vegetation from further damage in India whose economy is highly dependent on agricultural sector and may influence the global balance.

  18. Growth response to ozone of annual species from Mediterranean pastures

    International Nuclear Information System (INIS)

    Ozone (O3) phytotoxicity has been reported on a wide range of plant species. However, scarce information has been provided regarding the sensitivity of semi-natural grassland species, especially those from dehesa Mediterranean grasslands, in spite of their great biological diversity and the high O3 levels recorded in the region. A screening study was carried out in open-top chambers (OTCs) to assess the O3-sensitivity of representative therophytes of these ecosystems based on the response of selected growth-related parameters. Three O3 treatments and 3 OTCs per treatment were used. Legume species were very sensitive to O3, because 78% of the tested species showed detrimental effects on their total biomass relative growth rate (RGR) following their exposure to O3. The Trifolium genus was particularly sensitive showing O3-induced adverse effects on most of the assessed parameters. Gramineae plants were less sensitive than Leguminosae species because detrimental effects on total biomass RGR were only observed in 14% of the assessed species. No relationship was found between relative growth rates when growing in clean air and O3 susceptibility. The implications of these effects on the performance of dehesa acidic grasslands and on the definition of ozone critical levels for the protection of semi-natural vegetation are discussed. - Capsule: The therophytes from dehesa acidic pastures of central of the Iberian peninsula present a great sensitivity to ozone, as derived from growth- and biomass-related variables

  19. 77 FR 8197 - Implementation of the 2008 National Ambient Air Quality Standards for Ozone: Nonattainment Area...

    Science.gov (United States)

    2012-02-14

    ... )] that contribute to ground-level ozone concentrations...History of Nonattainment Area Classification Systems for the Ozone NAAQS...III. What are the proposed classification thresholds for nonattainment...ozone NAAQS? A. Proposed Classification Thresholds B....

  20. 40 CFR Appendix P to Part 50 - Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 2 2010-07-01 2010-07-01 false Interpretation of the Primary and Secondary National Ambient Air Quality Standards for Ozone P Appendix P to Part 50 Protection of Environment... STANDARDS Pt. 50, App. P Appendix P to Part 50—Interpretation of the Primary and Secondary National...

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Radial diffusive sampler for the determination of 8-h ambient ozone concentrations

    International Nuclear Information System (INIS)

    The 8-h ozone radial diffusive sampler was evaluated according to the CEN protocol for the validation of diffusive samplers. All the parameters regarding the sampler characteristics were found to be consistent with the requirements of this protocol apart from the blank value, which must be evaluated and subtracted at each sampling. The nominal uptake rate was determined in laboratory conditions. However, the uptake rate depends on the mass uptake, temperature, humidity and on the combination of temperature and humidity. Based on laboratory experiments, an empirical model has been established which improved the agreement between the radial sampler and the reference method. This improvement was observed under several different meteorological and emission conditions of sampling. By using the model equation of uptake rate, the data quality objective of 30% for the expanded uncertainty included in the O3 European Directive, is easily attained. Therefore, the sampler represents an appropriate indicative method. - A passive sampler has been fully validated for monitoring 8-h ozone concentrations in ambient air

  3. Radial diffusive sampler for the determination of 8-h ambient ozone concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Plaisance, H. [Laboratoire Central de Surveillance de la Qualite de l' Air - Ecole des Mines de Douai, Departement Chimie et Environnement, 941 rue Charles Bourseul, B.P. 838, 59508 Douai (France); Gerboles, M. [European Commission - DG Joint Research Centre, Institute for Environment and Sustainability, Transport and Air Quality Unit, I-21020 Ispra (Italy)]. E-mail: michel.gerboles@jrc.it; Piechocki, A. [Laboratoire Central de Surveillance de la Qualite de l' Air - Ecole des Mines de Douai, Departement Chimie et Environnement, 941 rue Charles Bourseul, B.P. 838, 59508 Douai (France); Detimmerman, F. [European Commission - DG Joint Research Centre, Institute for Environment and Sustainability, Transport and Air Quality Unit, I-21020 Ispra (Italy); Saeger, E. de [European Commission - DG Joint Research Centre, Institute for Environment and Sustainability, Transport and Air Quality Unit, I-21020 Ispra (Italy)

    2007-07-15

    The 8-h ozone radial diffusive sampler was evaluated according to the CEN protocol for the validation of diffusive samplers. All the parameters regarding the sampler characteristics were found to be consistent with the requirements of this protocol apart from the blank value, which must be evaluated and subtracted at each sampling. The nominal uptake rate was determined in laboratory conditions. However, the uptake rate depends on the mass uptake, temperature, humidity and on the combination of temperature and humidity. Based on laboratory experiments, an empirical model has been established which improved the agreement between the radial sampler and the reference method. This improvement was observed under several different meteorological and emission conditions of sampling. By using the model equation of uptake rate, the data quality objective of 30% for the expanded uncertainty included in the O{sub 3} European Directive, is easily attained. Therefore, the sampler represents an appropriate indicative method. - A passive sampler has been fully validated for monitoring 8-h ozone concentrations in ambient air.

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

    Energy Technology Data Exchange (ETDEWEB)

    Retzlaff, W.A.; Williams, L.E. (Univ. of California, Davis (United States) Kearney Agricultural Center, Parlier, CA (United States)); DeJong, T.M. (Univ. of California, Davis (United States))

    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 (O[sub 3]) 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 O[sub 3] partial pressures lasted from 1 June to 2 Nov. 1989. The mean 12-h [0800-2000 h Pacific Daylight Time (PDT)] O[sub 3] partial pressures measured in the open-top chambers during the experimental period were 0.038, 0.060, and 0.112 [mu]Pa Pa[sup [minus]1] O[sub 3] in the charcoal filtered, ambient, and ambient + O[sub 3] treatments, respectively. Leaf net CO[sub 2] assimilation, trunk cross-sectional area growth, and root, trunk, foliage, and total dry weight of Nonpareil were reduced by increased atmospheric O[sub 3] partial pressures. Mission was unaffected by O[sub 3] and Butte, Carmel, and Sonora were intermediate in their responses. Foliage of Nonpareil also abscised prematurely in the ambient and ambient + O[sub 3] treatments. The results indicate that there are almond cultivars that are sensitive to O[sub 3] exposure.

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

    International Nuclear Information System (INIS)

    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 ?Pa 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

  6. Non-Linear Concentration-Response Relationships between Ambient Ozone and Daily Mortality

    Science.gov (United States)

    Bae, Sanghyuk; Lim, Youn-Hee; Kashima, Saori; Yorifuji, Takashi; Honda, Yasushi; Kim, Ho; Hong, Yun-Chul

    2015-01-01

    Background Ambient ozone (O3) concentration has been reported to be significantly associated with mortality. However, linearity of the relationships and the presence of a threshold has been controversial. Objectives The aim of the present study was to examine the concentration-response relationship and threshold of the association between ambient O3 concentration and non-accidental mortality in 13 Japanese and Korean cities from 2000 to 2009. Methods We selected Japanese and Korean cities which have population of over 1 million. We constructed Poisson regression models adjusting daily mean temperature, daily mean PM10, humidity, time trend, season, year, day of the week, holidays and yearly population. The association between O3 concentration and mortality was examined using linear, spline and linear-threshold models. The thresholds were estimated for each city, by constructing linear-threshold models. We also examined the city-combined association using a generalized additive mixed model. Results The mean O3 concentration did not differ greatly between Korea and Japan, which were 26.2 ppb and 24.2 ppb, respectively. Seven out of 13 cities showed better fits for the spline model compared with the linear model, supporting a non-linear relationships between O3 concentration and mortality. All of the 7 cities showed J or U shaped associations suggesting the existence of thresholds. The range of city-specific thresholds was from 11 to 34 ppb. The city-combined analysis also showed a non-linear association with a threshold around 30-40 ppb. Conclusion We have observed non-linear concentration-response relationship with thresholds between daily mean ambient O3 concentration and daily number of non-accidental death in Japanese and Korean cities. PMID:26076447

  7. 40 CFR Appendix I to Part 50 - Interpretation of the 8-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-07-01

    ... Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT.... Primary and Secondary Ambient Air Quality Standards for Ozone. 2.1 Data Reporting and Handling Conventions... day is greater than the level of the ambient standard. 2.2 Primary and Secondary...

  8. The short-term effect of ambient ozone on mortality is modified by temperature in Guangzhou, China

    Science.gov (United States)

    Liu, Tao; Li, Tian Tian; Zhang, Yong Hui; Xu, Yan Jun; Lao, Xiang Qian; Rutherford, Shannon; Chu, Cordia; Luo, Yuan; Zhu, Qi; Xu, Xiao Jun; Xie, Hui Yan; Liu, Zhao Rong; Ma, Wen Jun

    2013-09-01

    Effects of ozone on mortality have been widely assessed in developed countries but rarely in developing countries, and the effects of season and temperature on these associations remain unclear. The present study aimed to explore the modifying effects of temperature on the association of ozone with mortality, and to examine the lag effect structure in Guangzhou, China. Daily non-accidental mortality, air pollution and meteorological data from January 1st 2006 to December 31st 2008 in Guangzhou were collected. Generalized additive models (GAM) and distributed lag models (DLM) were used to estimate the excess risk (ER) of ozone on daily mortality and capture the lag effect structure. Results revealed that, in cold season, an increment in the ozone concentration of 10 ?g m-3 was associated with a 0.87% (95% CI: -0.06 to 2.29%) and 3.34% (95%CI: 1.36-5.35%) increase of mortality for lag0 and lag0-6, respectively. However, no significant effects were observed in the warm season. Daily average temperature and ozone concentration had interactive negative effects on non-accidental mortality in the cold season and at daily average temperatures in the 0-25th percentile, and mortality displacement was also found in these conditions. Therefore, the short-term effect of ambient ozone on mortality is modified by temperature in Guangzhou, China.

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

    International Nuclear Information System (INIS)

    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.

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

    International Nuclear Information System (INIS)

    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)

  11. Is the growth of temperate forest trees enhanced along an ambient nitrogen deposition gradient?

    Science.gov (United States)

    Bedison, James E; McNeil, Brenden E

    2009-07-01

    The extent to which atmospheric N deposition is enhancing primary production and CO2 sequestration along the ambient N deposition gradients found within many regional temperate forest ecosystems remains unknown. We used tree diameter measurements from 1984 and 2004, allometric equations, and estimates of wet N deposition from 32 permanent plots located along an ambient N deposition gradient in the Adirondack Park, New York, U.S.A., to determine the effects of N deposition on the basal area and woody biomass increments (BAI and WBI, respectively) of individual stems from all the major tree species. Nitrogen deposition had either a neutral or positive effect on BAI and WBI, with the positive effects especially apparent within the smaller size classes of several species. The nature of these growth responses suggests that other co-varying factors (e.g., temperature, tropospheric ozone, soil acidification) may be partially counteracting the species-dependent fertilization effect of N deposition that was suggested by recent foliar N data across this gradient. Nevertheless, in documenting a fertilization effect from chronic, low-level, ambient rates of N deposition, this study underscores the need for more research on how N deposition is affecting rates of primary production, CO2 sequestration, and even vegetation dynamics in many forests worldwide. PMID:19694123

  12. Foliar response of black cherry (Prunus serotina) clones to ambient ozone exposure in central Pennsylvania.

    Science.gov (United States)

    Lee, J C; Skelly, J M; Steiner, K C; Zhang, J W; Savage, J E

    1999-06-01

    During late summer of 1996 and 1997 we examined ozone-induced foliar injury in a plantation of 111 black cherry trees (ramets) comprising 15 clones originating from wild ortets growing in the Allegheny National Forest, Pennsylvania, and the Monongahela National Forest, West Virginia. The experimental plantation was a clonal seed orchard in Centre County, Pennsylvania, started in 1971 using ortet buds grafted onto seedling rootstocks of mixed origin. Clones differed significantly in severity of foliar injury symptoms (F=31.83, p50% leaf area affected than other clones during both years. In contrast, clone R-14, which is from the same area in northcentral Pennsylvania as R-12, exhibited significantly less injury (LAA<6%). Although ambient O(3) concentrations were similar in both years, foliar injury was significantly greater (15.7%) in 1996 than in 1997 (9.9%). This is probably explained by lower stomatal conductance in 1997 caused by drier and hotter weather patterns in June and July of that year. Despite very different weather patterns and overall levels of injury in 1996 and 1997, mean clonal injury was significantly correlated between both years of assessment (r=0.92, p<0.001). Within tree crowns, foliage in lower and inner crown positions was significantly more injured than foliage in upper and exterior crown positions. There was no evidence of geographically based population differences in sensitivity to foliar O(3) injury. On the contrary, results demonstrate that wild genotypes of proximal geographic origin may differ greatly in sensitivity. PMID:15093074

  13. An automated monitoring system for VOC ozone precursors in ambient air: development, implementation and data analysis

    Energy Technology Data Exchange (ETDEWEB)

    Badol, C.; Borbon, A.; Locoge, N.; Leonardis, T.; Galloo, J.C. [Departement Chimie et Environnement, Ecole des Mines de Douai, 941 rue Charles Bourseul, BP 838, 59508, Douai Cedex (France)

    2004-04-01

    An automated system for the monitoring of volatile organic compound (VOC) ozone precursors in ambient air is described. The measuring technique consists of subambient preconcentration on a cooled trap followed by thermal desorption and GC/FID analysis. First, the technical development, which permits detection limits below 0.05 ppbv to be reached, proceeded in two steps: (1) the determination of optimum sampling parameters (trap composition and conditioning, outlet split, desorption temperature); (2) the development of a reliable calibration method based on a highly accurate standard. Then, a 4-year field application of the hourly measuring chain was carried out at two urban sites. On the one hand, quality control procedures provided the best VOC identification (peak assignment) and quantification (reproducibility, blank system control). On the other hand, the success and performances of the routine experience (88% of the measurements covered more than 40 target compounds) indicated the high quality and suitability of the instrumentation which is actually applied in several French air quality monitoring networks. Finally, an example of data analysis is presented. Data handling identified important organic compound sources other than vehicle exhaust. (orig.)

  14. 40 CFR Appendix H to Part 50 - Interpretation of the 1-Hour Primary and Secondary National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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.

  16. Growth Season Photochemical Pollution over the UK Based on 1990-2006 Ozone Data

    OpenAIRE

    Matasovi?, Brunislav; Klasinc, Leo; Cvitaš, Tomislav

    2013-01-01

    Ozone data from 13 rural and 11 urban sites for the growth season (April through September) during 1990-2006 have been analysed on the basis of recently introduced photochemical pollution indica-tors. The indicators predict that urban sites are prone to photochemical pollution, although compared to some rural sites, the urban sites have lower average ozone concentrations and showed lower values of time for which hourly average ozone concentration is above a threshold value. Interestingly, the...

  17. Effects of simultaneous ozone exposure and nitrogen loads on carbohydrate concentrations, biomass, and growth of young spruce trees (Picea abies)

    International Nuclear Information System (INIS)

    Spruce saplings were grown under different nitrogen fertilization regimes in eight chamberless fumigation systems, which were fumigated with either charcoal-filtered (F) or ambient air (O3). After the third growing season trees were harvested for biomass and non-structural carbohydrate analysis. Nitrogen had an overall positive effect on the investigated plant parameters, resulting in increased shoot elongation, biomass production, fine root soluble carbohydrate concentrations, and also slightly increased starch concentrations of stems and roots. Only needle starch concentrations and fine root sugar alcohol concentrations were decreased. Ozone fumigation resulted in needle discolorations and affected most parameters negatively, including decreased shoot elongation and decreased starch concentrations in roots, stems, and needles. In fine roots, however, soluble carbohydrate concentrations remained unaffected or increased by ozone fumigation. The only significant interaction was an antagonistic effect on root starch concentrations, where higher nitrogen levels alleviated the negative impact of ozone. - Simultaneous ozone fumigation and nitrogen fertilization have no synergistic impacts on carbohydrate concentrations, biomass, or growth of Picea abies saplings

  18. Estimate of biogenic VOC emissions in Japan and their effects on photochemical formation of ambient ozone and secondary organic aerosol

    Science.gov (United States)

    Chatani, Satoru; Matsunaga, Sou N.; Nakatsuka, Seiji

    2015-11-01

    A new gridded database has been developed to estimate the amount of isoprene, monoterpene, and sesquiterpene emitted from all the broadleaf and coniferous trees in Japan with the Model of Emissions of Gases and Aerosols from Nature (MEGAN). This database reflects the vegetation specific to Japan more accurately than existing ones. It estimates much lower isoprene emitted from other vegetation than trees, and higher sesquiterpene emissions mainly emitted from Cryptomeria japonica, which is the most abundant plant type in Japan. Changes in biogenic emissions result in the decrease in ambient ozone and increase in organic aerosol simulated by the air quality simulation over the Tokyo Metropolitan Area in Japan. Although newly estimated biogenic emissions contribute to a better model performance on overestimated ozone and underestimated organic aerosol, they are not a single solution to solve problems associated with the air quality simulation.

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

    Science.gov (United States)

    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...

  20. Responses of Fraxinus excelsior L. seedlings to ambient ozone exposure in urban and mountain areas based on physiological characteristics and antioxidant activity.

    Science.gov (United States)

    Parvanova, Petya; Tzvetkova, Nikolina; Bratanova-Doncheva, Svetla; Chipev, Nesho; Fikova, Radka; Donev, Evgeni

    2013-07-01

    Effects of ozone on the sensitive tree species Fraxinus excelsior L. exposed to ambient air were investigated. The dynamics of photosynthesis, transpiration, stomatal conductance and the activity of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in three-year-old ash seedlings were studied during a four-month period (June-September). Seedlings were exposed to ambient ozone in an urban (the Central City Park of Sofia - Borisova Gradina) and a mountain (Plana Mountain) area in Bulgaria. The sites were located near climate monitoring stations, providing data on ozone concentrations and meteorological parameters. Ozone exposure at the mountain site (AOT40) was more than two times higher compared to the urban site. Significantly higher values of sun radiation, transpiration, stomatal conductance and enzyme activity at the mountain site were also observed. At the urban site higher values of temperature and air humidity were registered. Effects of the measured variables on ash seedlings were complex and interdependent. No direct effect of ozone concentration in ambient air on the leaf physiology and biochemistry could be proved. However, intensified SOD and CAT activity in the presence of elevated ozone suggested antioxidant reaction in response to ozone uptake. PMID:23760537

  1. Ambient ozone concentration and its impact on forest vegetation in Lithuania.

    Science.gov (United States)

    Girgzdiene, Rasa; Serafinavici?te, Brigita; Stakenas, Vidas; Bycenkiene, Steigvile

    2009-12-01

    Continuous ozone concentration measurements at rural sites in Lithuania have been performed since 1982. Long-term ozone data show an increasing trend 0.4 ppb y(-1) in annual mean concentrations during the period 1982-2008, although ozone peak values show an insignificant tendency to decrease. Several studies were performed to evaluate the ozone effect on the main plant species of Lithuanian forests. A strong positive correlation was found between values for the accumulated doses over a threshold of 40 ppb index and the defoliation of Fraxinus excelsior trees in Lithuanian forests during 1991-2008. A strong correlation was found between ozone exposure and the proportion of healthy F. excelsior, Betula sp., and Alnus incana, trees indicating that in Lithuania the deciduous species are more sensitive to ozone than conifers and that healthier trees may be better indicators of the changing environment. The results of the studies suggest that the observed levels of ozone are sufficiently high to have negative effects on the vegetation in Lithuania. PMID:20175442

  2. Ambient volatile organic compounds and their effect on ozone production in Wuhan, central China.

    Science.gov (United States)

    Lyu, X P; Chen, N; Guo, H; Zhang, W H; Wang, N; Wang, Y; Liu, M

    2016-01-15

    Ambient volatile organic compounds (VOCs) were continuously measured from February 2013 to October 2014 at an urban site in Wuhan. The characteristics and sources of VOCs and their effect on ozone (O3) formation were studied for the first time. The total VOC levels in Wuhan were relatively low, and of all VOCs, ethane (5.2 ± 0.2 ppbv) was the species with the highest levels. Six sources, i.e., vehicular exhausts, coal burning, liquefied petroleum gas (LPG) usage, the petrochemical industry, solvent usage in dry cleaning/degreasing, and solvent usage in coating/paints were identified, and their contributions to the total VOCs were 27.8 ± 0.9%, 21.8 ± 0.8%, 19.8 ± 0.9%, 14.4 ± 0.9%, 8.5 ± 0.5%, and 7.7 ± 0.4%, respectively. Model simulation of a photochemical box model incorporating the Master Chemical Mechanism (PBM-MCM) indicated that the contribution to O3 formation of the above sources was 23.4 ± 1.3%, 22.2 ± 1.2%, 23.1 ± 1.7%, 11.8 ± 0.9%, 5.2 ± 0.4%, and 14.2 ± 1.1%, respectively. LPG and solvent usage in coating/paints were the sources that showed higher contributions to O3 formation, compared to their contributions to VOCs. The relative incremental reactivity (RIR) analysis revealed that the O3 formation in Wuhan was generally VOC-limited, and ethene and toluene were the primary species contributing to O3 production, accounting for 34.3% and 31.5% of the total RIR-weighted concentration, respectively. In addition, the contribution of CO to the O3 formation was remarkable. The C4 alkanes and alkenes from the LPG usage also significantly contributed to the O3 formation. The results can assist local governments in formulating and implementing control strategies for photochemical pollution. PMID:26410695

  3. Ozone

    Energy Technology Data Exchange (ETDEWEB)

    1978-02-01

    A joint report published by the U.K., the U.S., and France has recommended that further research is needed to quantify the damage to the ozone layer caused by propellants and certain fertilizers. However, the report described the effects of supersonic air flights on the ozone layers as ''neglilgible'', stating that a fleet of up to 35 Concorde aircraft would account for a small fraction of 1% of ozone destruction. Meanwhile, the U.S. Food and Drug Administration has compelled manufacturers of aerosol hairspray, deodorant, or antiperspirant that use chlorofluorocarbon (CFC) gases as a propellant to carry the health warning that it may harm public health and the environment by reducing ozone in the upper atmosphere. This public health warning is the beginning of a program adopted by U.S. agencies to ban CFC aerosols from interstate commerce by Apr. 1979.

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

    Directory of Open Access Journals (Sweden)

    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

  5. Determination of nitrogen dioxide, sulfur dioxide, ozone, and ammonia in ambient air using the passive sampling method associated with ion chromatographic and potentiometric analyses

    OpenAIRE

    Alaa A. Salem; Soliman, Ahmed A.; El-Haty, Ismail A.

    2009-01-01

    Concentrations of nitrogen dioxide (NO2), sulfur dioxide (SO2), ozone (O3), and ammonia (NH3) were determined in the ambient air of Al-Ain city over a year using the passive sampling method associated with ion chromatographic and potentiometric detections. IVL samplers were used for collecting nitrogen and sulfur dioxides whereas Ogawa samplers were used for collecting ozone and ammonia. Five sites representing the industrial, traffic, commercial, residential, and background regions of the ci...

  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

    International Nuclear Information System (INIS)

    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.

  7. COMBINED OZONE AND ACTIVE OXYGEN TREATMENT OF TOMATOES AND BANANAS DELAYS RIPENING AND REDUCES QUALITY DETERIORATION AND MICROBIAL GROWTH

    Science.gov (United States)

    Green bananas and mature tomatoes were subjected to a combination of ozone and active oxygen or ambient air (control) treatment at 10 'C for up to 25 days. Visual observation revealed that bananas stored in the active oxygen and ozone chamber remained greener than those stored in the control chambe...

  8. Effects of ozone on growth, lipid metabolism, and sporulation of fungi. [Colletotrichum lindemuthianum; Alternaria oleraceae

    Energy Technology Data Exchange (ETDEWEB)

    Treshow, M.; Harner, F.M.; Price, H.E.; Kormelink, J.R.

    1969-09-01

    Fumigations with ozone at concentrations of 10 pphm or more for 4 hr repeated daily for 4 days suppressed radial growth and spore production of Colletotrichum lindemuthianum, the most sensitive species studied. Neither radial nor mass growth of Alternaria oleraceae, a more tolerant species, was inhibited by 60 pphm ozone, although spore production was significantly accelerated. Since ozone did not affect spore viability, the inoculum potential was greatly enhanced. Histological effects of ozone included loss of pigmentation in C. lindemuthianum and abundant formation of light-refractive globules in the hyphae. Chemical analyses of mycelial mats showed an average 28% decrease in neutral lipid content of ozone-fumigated cultures. No differences were detectable in fatty acid composition of fumigated cultures. While some lipids may have leaked into the substrate, it was suspected that ozone penetrated into vital sites within the cell-oxidizing sulfhydryl groups, thereby suppressing lipid synthesis. The actual degree of suppression in fumigated hyphae may have been greater than indicated, since much of the mycelia analyzed grew within the substrate and was not directly subjected to ozone. 14 references.

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

    Science.gov (United States)

    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.

  10. INFLAMMATORY RESPONSE IN HUMAN LUNG EXPOSED TO AMBIENT LEVELS OF OZONE

    Science.gov (United States)

    Although ozone (O3) has been shown to induce inflammation in the lungs of animals, very little is known about its inflammatory effects on humans. In the study, eleven healthy non-smoking males, ages 18-35 were exposed once to 0.4 ppm O3 and once to filtered air for two hours with...

  11. How closely does stem growth of adult beech (Fagus sylvatica) relate to net carbon gain under experimentally enhanced ozone stress?

    International Nuclear Information System (INIS)

    The hypothesis was tested that O3-induced changes in leaf-level photosynthetic parameters have the capacity of limiting the seasonal photosynthetic carbon gain of adult beech trees. To this end, canopy-level photosynthetic carbon gain and respiratory carbon loss were assessed in European beech (Fagus sylvatica) by using a physiologically based model, integrating environmental and photosynthetic parameters. The latter were derived from leaves at various canopy positions under the ambient O3 regime, as prevailing at the forest site (control), or under an experimental twice-ambient O3 regime (elevated O3), as released through a free-air canopy O3 fumigation system. Gross carbon gain at the canopy-level declined by 1.7%, while respiratory carbon loss increased by 4.6% under elevated O3. As this outcome only partly accounts for the decline in stem growth, O3-induced changes in allocation are referred to and discussed as crucial in quantitatively linking carbon gain with stem growth. - Highlights: ? We model O3-induced changes in the photosynthetic carbon gain of adult beech trees. ? Elevated O3 decreases gross carbon gain but increases respiratory carbon loss. ? Reduction in net carbon gain only partly accounts for the decline in stem growth. ? O3 effects on the whole-tree allocation is crucial in addition to carbon gains. - Reduction in net carbon gain at the canopy level only partly accounts for the decline in stem growth under elevated ozone.

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

    International Nuclear Information System (INIS)

    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.

  13. Health effects of tropospheric ozone: Review of recent research findings and their implications to ambient air quality standards

    International Nuclear Information System (INIS)

    The US Environmental Protection Agency (EPA) Administrator proposed (on August 3, 1992) to retain the current National Ambient Air Quality Standard (NAAQS) for ozone (O3) on the basis of data assembled in a draft Criteria Document (1986) and its Addendum (1988) which, together with a draft Staff Paper (1988), received public comment and review comments by the EPA's Clean Air Scientific Advisory Committee (CASAC). This paper summarizes and discusses research findings presented since 1988 which, based on the author's experience as a Chairman of CASAC, are most relevant to the promulgation of a primary (health based) NAAQS for O3. These newer findings include substantial evidence from controlled chamber exposure studies and field studies in natural settings that the current NAAQS contains no margin of safety against short-term effects that the EPA has considered to be adverse. They also include evidence from epidemiologic studies that current ambient exposures are associated with reduced baseline lung function, exacerbation of asthma and premature mortality, as well as evidence from chronic animal exposure studies at concentrations within current ambient peak levels that indicate progressive and persistent lung function and structural abnormalities. The current NAAQS, if retained, may therefore also be inadequate to protect the public from effects resulting from chronic exposure to O3. 96 refs

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

    Science.gov (United States)

    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...

  15. The temporal pattern of mortality responses to ambient ozone in the APHEA project.

    OpenAIRE

    Samoli, E; A. Zanobetti; J. Schwartz; Atkinson, R.; Le Tertre, A; Schindler, C; Pérez, L.; Cadum, E; Pekkanen, J; Paldy, A; Touloumi, G.; Katsouyanni, K.

    2009-01-01

    Abstract Background: We investigated the temporal pattern of effects of summertime ozone (O3) in total, cardiovascular and respiratory mortality in 21 European cities participating in the APHEA-2 project, which is fundamental in determining the importance of the effect in terms of life loss. Methods: Data from each city were analyzed separately using distributed lag models with up to 21 lags. City specific air pollution estimates were regressed on city specific cova...

  16. Impact of ozone on the growth of birch (Betula pendula) saplings

    International Nuclear Information System (INIS)

    Significant correlation was found between reductions of growth and daylight AOT40 for Betula pendula saplings. - Saplings of one half-sib family of birch, Betula pendula, were exposed to three levels of ozone in open-top chambers (OTCs) during two growing seasons 1997-1998. The ozone treatments were non-filtered air (NF, accumulated daylight AOT40 over the two growing seasons of 3.0 ?l l-1 h), non-filtered air with extra ozone (NF+, accumulated daylight AOT40 of 27.3 ?l l-1 h) and non-filtered air with additional extra ozone (NF++, accumulated daylight AOT40 of 120 ?l l-1 h). The birch saplings, including the roots, were harvested after the first and second growing seasons. After the first growing season, the NF++ treatment reduced the total wood biomass by 22%, relative to the NF treatment. There was no further reduction of the total wood biomass in the NF++ treatment after the second growing season. The root biomass was reduced by 30% after the first growing season. The shoot/root ratio, as well as the proportional biomass of leaves, were increased by ozone during both years. The ozone impact on the relative growth rate was estimated to -2% per 10 ?l l-1 h daylight AOT40 per growing season

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. Growth response to ozone of annual species from Mediterranean pastures

    OpenAIRE

    Gimeno, Benjamín; Bermejo, V.; Sanz, J.; Torre Llorente, Daniel de la; Elvira, S.

    2004-01-01

    Ozone (O3) phytotoxicity has been reported on a wide range of plant species. However, scarce information has been provided regarding the sensitivity of semi-natural grassland species, especially those from dehesa Mediterranean grasslands, in spite of their great biological diversity and the high O3 levels recorded in the region. A screening study was carried out in open-top chambers (OTCs) to assess the O3-sensitivity of representative therophytes of these ecosystems based on the response of ...

  19. EVALUATION OF VARIOUS ALTERNATIVE AMBIENT OZONE STANDARDS BASED ON CROP YIELD LOSS DATA

    Science.gov (United States)

    Under the Clean Air Act, the U.S. Environmental Protection Agency establishes primary and secondary national ambient air quality standards (NAAQSs) to protect public health and welfare from known or anticipated adverse effects from criteria air pollutants. he objectives of this p...

  20. Growth response to a changing environment-Impacts of tropospheric ozone dose on photosynthesis of Norway spruce forests in Austria

    Science.gov (United States)

    Liu, Xiaozhen; Pietsch, Stephan; Hasenauer, Hubert

    2010-05-01

    Tropospheric ozone is an important air pollutant, although plants have active defense strategies (e.g. antioxidants), the cumulative ozone dose may lead to chronic damages to plant tissues. Ozone enters into plants through stomata and reacts with other chemicals to create toxic compounds. This affects plant photosynthesis and may reduce CO2 fixation, and consequently growth. Open top cambers (OTC) are usually used to study the effects of elevated ozone levels on photosynthesis; whereas field studies with on site occurring ozone levels are rare. A recent modelling study on Norway spruce stands in Austria exhibited trends in model errors indicating that an increase in ozone dose leads to a reduction in volume increment. This study aims to explore how different ozone doses affect photosynthesis under field conditions and may translate into growth response for 12 stands of Norway spruce, distributed along an ozone concentration gradient across Austria. A LI-6400xt photosynthesis system was utilized to collect physiological parameters including net photosynthesis, stomata conductance, internal CO2 concentration, transpiration, etc. Chlorophyll fluorescence data was collected by using a PEA chlorophyll fluorescence meter, and chlorophyll content was measured. Morphological characteristics and soil samples were also analyzed. Ozone dose to leaf tissue was calculated from external ozone concentration, the conductance of the stomata to ozone, the leaf area index and the time span of the day when ozone uptake takes place. Our results confirm that increasing cumulative ozone dose reduces maximum assimilation rate and carboxylation efficiency under field conditions. Our final goal is to quantify how far this ozone induced reduction in assimilation power ultimately translates into a growth reduction of Norway spruce in Austria.

  1. Growth and premature leaf fall in American aspen as bioindications for ozone.

    Science.gov (United States)

    Keller, T

    1988-01-01

    Several clones of the American aspen (Populus tremuloides Michx.) differing in ozone sensitivity were fumigated continuously for 105 days with different ozone concentrations, producing different ozone doses. The suitability of the clones as possible replacements for tobacco as bioindicators in forested areas was tested. The life span of leaves of the ozone-sensitive clones was distinctly reduced by ozone. The difference to controls was significant even in the relatively clean air at Birmensdorf. Growth was diminished, too, but the decrease in height was much less pronounced than that in weight. In sensitive clones an after-effect was detectable, since the weight of new shoots (grown from reserves) decreased with increasing ozone stress in the previous year. Since the tolerant clone grew less, it is-at first sight-of decreased economic interest from the point of view of rapid productivity. In the long run, however, it might be economically interesting because it may be able to maintain productivity (although at a lower level) due to better competitive strength. PMID:15092605

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

    International Nuclear Information System (INIS)

    Beech seedlings were grown under different nitrogen fertilisation regimes (0, 20, 40, and 80 kg N ha-1 yr-1) for three years and were fumigated with either charcoal-filtered (F) or ambient air (O3). 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-1 yr-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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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.

  5. Reduction of stem growth and site dependency of leaf injury in Massachusetts black cherries exhibiting ozone symptoms

    International Nuclear Information System (INIS)

    Ozone symptomatic trees had a reduced stem growth and symptom expression was enhanced on moister and better growing stands. - Leaf ozone symptoms in natural ecosystems are increasingly reported but ozone effects on tree growth and the mediation of site conditions are still little documented. This study tests two hypotheses: (1) leaf injury in black cherry is associated with decline in radial growth, (2) symptoms are more prevalent on mesic sites. On sites supporting black cherry across Massachusetts, tree growth and leaf ozone injury were surveyed in 1996 using a randomized plot network established in the 1960s. Forty-seven percent of 120 trees sampled for ozone symptoms were symptomatic with generally low levels of injury. Over a 31-year period symptomatic trees had 28% lower stem growth rates than asymptomatic trees. Ozone symptom expression was enhanced in well growing stands on moister, cooler and more elevated sites. Ozone appeared to increase environmental stress and had a more pronounced effect on growth in better growing black cherry stands. This complicates management decisions as thinning increases growth and moisture availability

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

    International Nuclear Information System (INIS)

    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 (?L) 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Schaub, M. [Graduate Ecology Program, Pennsylvania State University, University Park, PA 16802 (United States); Skelly, J.M. [Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802 (United States)]. E-mail: jms34@psu.edu; Zhang, J.W. [Penn State Institutes of the Environment, Pennsylvania State University, University Park, PA 16802 (United States); Ferdinand, J.A. [Penn State Institutes of the Environment, Pennsylvania State University, University Park, PA 16802 (United States); Savage, J.E. [Penn State Institutes of the Environment, Pennsylvania State University, University Park, PA 16802 (United States); Stevenson, R.E. [Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802 (United States); Davis, D.D. [Department of Plant Pathology, Pennsylvania State University, University Park, PA 16802 (United States); Steiner, K.C. [School of Forest Resources, Pennsylvania State University, University Park, PA 16802 (United States)

    2005-02-01

    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 ({psi}{sub L}) were detected for all three species indicating no differing soil moisture conditions across the sites. Significant variation in stomatal conductance for water vapor (g{sub wv}) was found among species, soil moisture, time of day and sample date. When comparing cumulative ozone uptake and decreased photosynthetic activity (P{sub n}), red maple was the only species to show higher gas exchange under mesic vs. drier soil conditions (P < 0.05). The inconsistent differences in gas exchange response within the same crowns of ash and the uncoupling relationship between g{sub wv} and P{sub n} 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.

  8. Ozone affects gas exchange, growth and reproductive development in Brassica campestris (Wisconsin fast plants).

    Science.gov (United States)

    Black, V J; Stewart, C A; Roberts, J A; Black, C R

    2007-01-01

    Exposure to ozone (O(3)) may affect vegetative and reproductive development, although the consequences for yield depend on the effectiveness of the compensatory processes induced. This study examined the impact on reproductive development of exposing Brassica campestris (Wisconsin Fast Plants) to ozone during vegetative growth. Plants were exposed to 70 ppb ozone for 2 d during late vegetative growth or 10 d spanning most of the vegetative phase. Effects on gas exchange, vegetative growth, reproductive development and seed yield were determined. Impacts on gas exchange and foliar injury were related to pre-exposure stomatal conductance. Exposure for 2 d had no effect on growth or reproductive characteristics, whereas 10-d exposure reduced vegetative growth and reproductive site number on the terminal raceme. Mature seed number and weight per pod and per plant were unaffected because seed abortion was reduced. The observation that mature seed yield per plant was unaffected by exposure during the vegetative phase, despite adverse effects on physiological, vegetative and reproductive processes, shows that indeterminate species such as B. campestris possess sufficient compensatory flexibility to avoid reductions in seed production. PMID:17803646

  9. Effect of increased carbon dioxide concentrations on stratospheric ozone

    International Nuclear Information System (INIS)

    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

  10. Ambient formaldehyde and its contributing factor to ozone and OH radical in a rural area

    Science.gov (United States)

    Xiaoyan, Wang; Huixiang, Wang; Shaoli, Wang

    2010-06-01

    Formaldehyde (HCHO), as well as correlative pollutants was measured from 1 to 31 July in 2007 at Mazhuang, a rural site located in the east of China. Gaseous HCHO was scrubbed from the air with an acidic 2,4-dinitrophenylhydrazine (DNPH) solution, which leaded to the reaction of HCHO with DNPH and produced a stable product, 2,4-dinitrophenylhydrazone, followed by online analysis by high-performance liquid chromatography (HPLC) coupled with Ultraviolet detector. During the observation period, mixing ratios of HCHO ranged from 0.2 ppbv to 6.2 ppbv, with an average of 1.5 ± 0.67 ppbv. HCHO shows an evident diurnal variation, the maximum appeared during 12:00-14:00. The average concentration diurnal variations of measured HCHO, ozone (O 3), Methylhydroperoxides (MHP, CH 3OOH), hydrogen peroxide (H 2O 2), nitrogen oxides (NO x) and meteorological parameters were compared. The similar variations of HCHO, O 3 and radiation imply that photo-oxidation of hydrocarbons might be the major source for HCHO. Based on the maximum incremental reactivity (MIR) coefficient of HCHO, the calculation shows that HCHO contributes about 20% to total observed O 3 during the study period. In order to compare the contributions of O 3, HCHO and HONO to OH radical, photolysis rate parameters ( J-values) of the three compounds were calculated by the Tropospheric Ultraviolet and Visible (TUV) Radiation Model (4.4 version). Based on the comparison, this study reaches the conclusion that O 3 is the dominant source of OH radical at Mazhuang. This study also uses P(HCHO)/P(O 3) which represents the ratio of contrbutions of HCHO and O 3 to OH radical, to discuss the action of HCHO in OH radical soucers. The result shows that P(HCHO)/P(O 3) is 12.5% on average, with the maximum of 21.0% at 13:00 P.M. and minimum of 7.5% before 9:00 A.M. and after 17:00 P.M..Therefore HCHO is also an important source of OH radical and cannot be ignored.

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

    Science.gov (United States)

    Schaub, M; Skelly, J M; Zhang, J W; Ferdinand, J A; Savage, J E; Stevenson, R E; Davis, D D; Steiner, K C

    2005-02-01

    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 (psi(L)) were detected for all three species indicating no differing soil moisture conditions across the sites. Significant variation in stomatal conductance for water vapor (g(wv)) was found among species, soil moisture, time of day and sample date. When comparing cumulative ozone uptake and decreased photosynthetic activity (P(n)), red maple was the only species to show higher gas exchange under mesic vs. drier soil conditions (P < 0.05). The inconsistent differences in gas exchange response within the same crowns of ash and the uncoupling relationship between g(wv) and P(n) demonstrate the strong influence of heterogeneous environmental conditions within forest canopies. PMID:15519730

  12. Sensitivity of photosynthesis and stomatal conductance in mature beech (Fagus sylvatica L.) to ambient or experimentally enhanced ozone regimes

    OpenAIRE

    Löw, Markus

    2007-01-01

    During the years 2003 and 2004, the influence of experimentally enhanced ozone concentrations (by means of “free-air" fumigation) on the photosynthetic rate and stomatal conductance of 60-year-old beech trees was examined and compared to control trees of same age growing under unchanged ozone concentrations at the same site. The drought of 2003 enabled to quantify the effects of increased ozone concentrations under limited water supply. Aims of the study were to quantify the influence of cli...

  13. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Growth response of Pinus ponderosa seedlings and mature tree branches to acid rain and ozone exposure

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, P.D. [USDA Forest Service, Forestry Sciences Lab., Rhinelander, WI (United States); Houpis, J.L.J. [Lawrence Livermore National Lab., CA (United States); Helms, J.A. [California Univ., Berkeley, CA (United States). Dept. of Environmental Science Policy and Management

    1994-10-01

    Forests of the central and southern Sierra Nevada in California have been subjected to chronic damage by ozone and other atmospheric pollutants for the past several decades. Until recently, pollutant exposure of northern Sierra Nevada forests has been mild but increasing population and changes in land use throughout the Sacramento Valley and Sierra Nevada foothills may lead to increased pollutant damage in these forests. Although, better documented in other regions of the United States, little is known regarding the potential for acidic precipitation damage to Sierra Nevada forests. Only recently have studies directed towards understanding the potential interactive effects of ozone and acidic precipitation been undertaken. A key issue in resolving potential regional impacts of pollutants on forests is the extent to which research results can be scaled across genotypes and life-stages. Most of the pollution research to date has been performed using seedlings with varying degrees of genetic control. It is important to determine if the results obtained in such studies can be extrapolated to mature trees and to different genetic sources. In this paper, we present results from a one-year study examining the interactive effects of foliar exposure to acidic rain and ozone on the growth of ponderosa pine (Pinus ponderosa), a conifer known to be sensitive to ozone. The response to pollutants is characterized for both seedlings and mature tree branches of three genotypes grown in a common environment.

  15. Growth response of Pinus ponderosa seedlings and mature tree branches to acid rain and ozone exposure

    International Nuclear Information System (INIS)

    Forests of the central and southern Sierra Nevada in California have been subjected to chronic damage by ozone and other atmospheric pollutants for the past several decades. Until recently, pollutant exposure of northern Sierra Nevada forests has been mild but increasing population and changes in land use throughout the Sacramento Valley and Sierra Nevada foothills may lead to increased pollutant damage in these forests. Although, better documented in other regions of the United States, little is known regarding the potential for acidic precipitation damage to Sierra Nevada forests. Only recently have studies directed towards understanding the potential interactive effects of ozone and acidic precipitation been undertaken. A key issue in resolving potential regional impacts of pollutants on forests is the extent to which research results can be scaled across genotypes and life-stages. Most of the pollution research to date has been performed using seedlings with varying degrees of genetic control. It is important to determine if the results obtained in such studies can be extrapolated to mature trees and to different genetic sources. In this paper, we present results from a one-year study examining the interactive effects of foliar exposure to acidic rain and ozone on the growth of ponderosa pine (Pinus ponderosa), a conifer known to be sensitive to ozone. The response to pollutants is characterized for both seedlings and mature tree branches of three genotypes grown in a common environment

  16. Impact of experimentally elevated ozone on seed germination and growth of Russian pine (Pinus sylvestris) and spruce (Picea spp.) provenances.

    Science.gov (United States)

    Prozherina, Nadezda; Nakvasina, Elena; Oksanen, Elina

    2009-12-01

    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, Finland, over a span of 2 y. The AOT40 value (accumulated ozone dose over the threshold 40 ppb during daylight hours) was 11 ppm hr per growing season, which was 1.4 times higher than the ambient air concentration. The plants were measured for germination rate; shoot increment; needle length; and dry mass of needles, shoots, and roots. Significant differences between pine and spruce provenance response to ozone were found in all parameters. Ozone stress immediately reduced the germination rate of Northern pine provenances, whereas biomass reductions became evident during the second year of the exposure in all pine provenances. Spruce species were more tolerant to elevated ozone concentrations. Our results indicate that seedling development is vulnerable to increasing ozone concentrations and that attention must be paid to the provenance selection. PMID:20175444

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

    International Nuclear Information System (INIS)

    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)

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

    International Nuclear Information System (INIS)

    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)

  19. Meta-analysis of the association between short-term exposure to ambient ozone and respiratory hospital admissions

    International Nuclear Information System (INIS)

    Ozone is associated with health impacts including respiratory outcomes; however, results differ across studies. Meta-analysis is an increasingly important approach to synthesizing evidence across studies. We conducted meta-analysis of short-term ozone exposure and respiratory hospitalizations to evaluate variation across studies and explore some of the challenges in meta-analysis. We identified 136 estimates from 96 studies and investigated how estimates differed by age, ozone metric, season, lag, region, disease category, and hospitalization type. Overall results indicate associations between ozone and various kinds of respiratory hospitalizations; however, study characteristics affected risk estimates. Estimates were similar, but higher, for the elderly compared to all ages and for previous day exposure compared to same day exposure. Comparison across studies was hindered by variation in definitions of disease categories, as some (e.g., asthma) were identified through ? 3 different sets of ICD codes. Although not all analyses exhibited evidence of publication bias, adjustment for publication bias generally lowered overall estimates. Emergency hospitalizations for total respiratory disease increased by 4.47% (95% interval: 2.48, 6.50%) per 10 ppb 24 h ozone among the elderly without adjustment for publication bias and 2.97% (1.05, 4.94%) with adjustment. Comparison of multi-city study results and meta-analysis based on single-city studies further suggested publication bias.

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

    International Nuclear Information System (INIS)

    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 ?L-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 nondestructively using the LICOR LAI-2000 Plant Canopy Analyzer. Also, treatment differences for normalized difference vegetation index (ND) were only observed for wheat plants from the high-Oa and ambient CO2 treatment, at some growing stages. Otherwise, ND data were not helpful for identifying damage due to O3 fumigation or benefits due to CO2 enrichment. Significant interactive effects of CO2 vs. O3 were observed only for wheat grain yield in 1991 (p < 0.10), indicated that the detrimental effect of Oa air pollution was more than overcome under the CO2-enriched environment. (author)

  1. 77 FR 28423 - Final Rule To Implement the 1997 8-Hour Ozone National Ambient Air Quality Standard...

    Science.gov (United States)

    2012-05-14

    ...available on the World Wide Web. A copy of this notice...the 1997 ozone NAAQS. Based on the area classifications...by operation of law'' based on the ``design value...these designated areas are based on coordinates of latitude...from EPA Region 9's GIS database and are...

  2. Forming High Ozone Concentration in the Ambient Air of Southern Taiwan under the Effects of Western Pacific Subtropical High

    OpenAIRE

    Kuo-Cheng Lo; Chung-Hsuang Hung

    2015-01-01

    Due to the distinct geographical and meteorological conditions of Taiwan, air pollutants concentrations in the ambient air of it may vary with seasons. Accordingly, this study aimed to investigate the formation of high O3 concentration in the ambient air of Southern Taiwan during summers. A high O3 concentration case occurring between June 28 and July 2, 2013, was modeled and analyzed with WRF-Chem meteorological and air quality model. During the investigated period, a typical western Pacific...

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

    International Nuclear Information System (INIS)

    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

  4. Ozone exposure induces the activation of leaf senescence-related processes and morphological and growth changes in seedlings of Mediterranean tree species

    International Nuclear Information System (INIS)

    Four Mediterranean tree taxa, Quercus ilex subsp. ilex, Quercus ilex subsp. ballota, Olea europaea cv. vulgaris and Ceratonia siliqua, were exposed to different ozone (O3) concentrations in open top chambers (OTCs) during 2 years. Three treatments were applied: charcoal-filtered air (CF), non-filtered air (NF) and non-filtered air plus 40 ppbv of O3 (NF+). The photochemical maximal efficiency, Fv/Fm, decreased in NF+ plants during the second year of exposure, especially during the most stressful Mediterranean seasons (winter and summer). An increase of ?13C was found in three of the four studied species during the first year of exposure. This finding was only maintained in C. siliqua during the second year. Decreases in the chlorophyll content were detected during the first year of fumigations in all the species studied, but not during the second year. The NF+ treatment induced changes in foliar anatomical characteristics, especially in leaf mass per area (LMA) and spongy parenchyma thickness, which increased in some species. A reduction in N content and an increase in ?15N were found in all species during the second year when exposed in the NF+ OTCs, suggesting a change in their retranslocation pattern linked to an acceleration of leaf senescence, as also indicated by the above mentioned biochemical and anatomical foliar changes. The two Q. ilex subspecies were the most sensitive species since the changes in N concentration, ?15N, chlorophyll, leaf area, LMA and biomass occurred at ambient O3 concentrations. However, C. siliqua was the most responsive species (29% biomass reduction) when exposed to the NF+ treatment, followed by the two Q. ilex subspecies (14-20%) and O. europaea (no significant reduction). Ozone resistance of the latter species was linked to some plant traits such as chlorophyll concentrations, or spongy parenchyma thickness. - Ozone induces species-specific leaf senescence-related processes and morphological and growth changes in seedlings of Mediterranean tree species

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

    Science.gov (United States)

    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 upper level excessive winds as the low pressure front approached. However the flight was still able to capture a temperature profile indicating a well-mixed atmosphere below about 300 m AGL, sealed by a definitive inversion layer extending to the top of the measurement profile. The measured O3 profile went from about 140 ppb near the ground to around 60 ppb at the start of the inversion layer, and then remained essentially constant until the top of the elevation profile. The vertical profile late in the morning of the following day (after the front had passed), showed nearly straight vertical profiles of temperature (≈2°C) and ozone (35-50 ppb) up to approximately 2400 m ASL (820 m AGL). The stacked horizontal profiles (1650 and 1750 m ASL) flown immediately after the vertical flight of Feb. 17th showed some differences on the horizontal scale, but it was unclear if these differences were associated with terrain differences (topography dropped rapidly to the south) or locational differences in precursor sources. The UAV measured ozone compared favorably to nearby co-investigators (NOAA/ESRL CSD TOPAZ Lidar and CU/INSTAAR tethered balloon).

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

    International Nuclear Information System (INIS)

    Potato (Solanum tuberosum cv. Bintje) was grown in open-top chambers under three carbon dioxide (ambient and seasonal mean concentrations of 550 and 680 ?mol 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 ?mol 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)

  7. Test Standard Developed for Determining the Slow Crack Growth of Advanced Ceramics at Ambient Temperature

    Science.gov (United States)

    Choi, Sung R.; Salem, Jonathan A.

    1998-01-01

    The service life of structural ceramic components is often limited by the process of slow crack growth. Therefore, it is important to develop an appropriate testing methodology for accurately determining the slow crack growth design parameters necessary for component life prediction. In addition, an appropriate test methodology can be used to determine the influences of component processing variables and composition on the slow crack growth and strength behavior of newly developed materials, thus allowing the component process to be tailored and optimized to specific needs. At the NASA Lewis Research Center, work to develop a standard test method to determine the slow crack growth parameters of advanced ceramics was initiated by the authors in early 1994 in the C 28 (Advanced Ceramics) committee of the American Society for Testing and Materials (ASTM). After about 2 years of required balloting, the draft written by the authors was approved and established as a new ASTM test standard: ASTM C 1368-97, Standard Test Method for Determination of Slow Crack Growth Parameters of Advanced Ceramics by Constant Stress-Rate Flexural Testing at Ambient Temperature. Briefly, the test method uses constant stress-rate testing to determine strengths as a function of stress rate at ambient temperature. Strengths are measured in a routine manner at four or more stress rates by applying constant displacement or loading rates. The slow crack growth parameters required for design are then estimated from a relationship between strength and stress rate. This new standard will be published in the Annual Book of ASTM Standards, Vol. 15.01, in 1998. Currently, a companion draft ASTM standard for determination of the slow crack growth parameters of advanced ceramics at elevated temperatures is being prepared by the authors and will be presented to the committee by the middle of 1998. Consequently, Lewis will maintain an active leadership role in advanced ceramics standardization within ASTM. In addition, the authors have been and are involved with several international standardization organizations including the Versailles Project on Advanced Materials and Standards (VAMAS), the International Energy Agency (IEA), and the International Organization for Standardization (ISO). The associated standardization activities involve fracture toughness, strength, elastic modulus, and the machining of advanced ceramics.

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

    International Nuclear Information System (INIS)

    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 (?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 (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 variability in stomatal response may be due to inherent differences

  9. 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

    Energy Technology Data Exchange (ETDEWEB)

    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)

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. Ozone decomposition on Ag/SiO{sub 2} and Ag/clinoptilolite catalysts at ambient temperature

    Energy Technology Data Exchange (ETDEWEB)

    Nikolov, Penko, E-mail: penmail@mail.bg [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Genov, Krassimir; Konova, Petya [Institute of General and Inorganic Chemistry, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Milenova, Katya; Batakliev, Todor; Georgiev, Vladimir [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria); Kumar, Narendra [Laboratory of Industrial Chemistry, Process Chemistry Centre, Abo Akademi University, Biskopsgatan 8, 20500 Abo/Turku (Finland); Sarker, Dipak K. [School of Pharmacy and Biomolecular Sciences, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom); Pishev, Dimitar [University of Chemical Technology and Metallurgy, 1756 Sofia (Bulgaria); Rakovsky, Slavcho [Institute of Catalysis, Bulgarian Academy of Sciences, 1113 Sofia (Bulgaria)

    2010-12-15

    Silver modified zeolite (Bulgarian natural clinoptilolite) and Ag/silica catalysts were synthesized by ion exchange and incipient wet impregnation method respectively and characterized by different techniques. DC arc-AES was used for Ag detection. XRD spectra show that Ag is loaded over the surface of the SiO{sub 2} sample and that after the ion-exchange process the HEU type structure of clinoptilolite is retained. UV-VIS (specific reflection at 310 nm) and IR (band at 695 cm{sup -1}) spectroscopy analysis proved that silver is loaded as a T-atom into zeolite channels as Ag{sup +}, instead of Na{sup +}, Ca{sup 2+}, or K{sup +} ions, existing in the natural clinoptilolite form. The samples Ag/SiO{sub 2} and Ag-clinoptilolite were tested as catalysts for decomposition of gas phase ozone. Very high catalytic activity (up to 99%) was observed and at the same time the catalysts remained active over time at room temperature.

  14. Ozone Nonattainment Areas

    Data.gov (United States)

    U.S. Environmental Protection Agency — This data layer identifies areas in the U.S. where air pollution levels have not met the National Ambient Air Quality Standards (NAAQS) for ozone and have been...

  15. The Effects of Ambient Ions on the Growth of Gold Nanoparticles by Laser Ablation in Liquid

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Hyejin; Kim, Kuk Ki; Song, Jae Kyu; Park, Seung Min [Kyung Hee Univ., Seoul (Korea, Republic of)

    2014-03-15

    Gold nanoparticles (AuNPs) were synthesized by laser (Nd:YAG, ? = 1064 nm) ablation of a gold target immersed in various aqueous electrolyte solutions (7 mM of LiCl, NaCl, KCl, NaBr, and NaI) as well as in deionized water. The surface plasmon absorption and EDX of AuNPs so produced as well as their TEM images were analyzed to investigate the effects of ambient ions on the growth and aggregation of NPs. The size of AuNPs was reduced by laser ablation in the presence of chloride and bromide ions while it increased drastically when AuNPs were formed in iodide solution. Interestingly, triangular nanoplates were synthesized only in iodide solution. Surface chemistry on AuNPs in various electrolyte solutions was explored to elucidate the role of ions on the size and stability of AuNPs.

  16. The Effects of Ambient Ions on the Growth of Gold Nanoparticles by Laser Ablation in Liquid

    International Nuclear Information System (INIS)

    Gold nanoparticles (AuNPs) were synthesized by laser (Nd:YAG, ? = 1064 nm) ablation of a gold target immersed in various aqueous electrolyte solutions (7 mM of LiCl, NaCl, KCl, NaBr, and NaI) as well as in deionized water. The surface plasmon absorption and EDX of AuNPs so produced as well as their TEM images were analyzed to investigate the effects of ambient ions on the growth and aggregation of NPs. The size of AuNPs was reduced by laser ablation in the presence of chloride and bromide ions while it increased drastically when AuNPs were formed in iodide solution. Interestingly, triangular nanoplates were synthesized only in iodide solution. Surface chemistry on AuNPs in various electrolyte solutions was explored to elucidate the role of ions on the size and stability of AuNPs

  17. Radiation utilization efficiency and the growth of soybeans exposed to ozone: a comparative analysis

    International Nuclear Information System (INIS)

    Effects of ozone (O3) on field-planted soybeans (Glycine max (L.) Merr. ‘Davis’) were examined using a simple crop-growth model that resolves the rate of increase in crop dry weight into the total amount of radiation intercepted by a crop canopy and the efficiency of conversion of this energy into dry matter (?, termed utilization efficiency). The objectives were : (1) to examine the effects of O3 on light interception and ?, and compare these results with a similar study by Unsworth et al. to determine whether the effects of O3 are consistent from year to year, and (2) to determine whether ? is more sensitive to O3 during reproductive than vegetative growth and whether allocation of aboveground biomass to seed is affected by O3. Five O3 concentrations (seasonal means of 30, 52, 57, 76 and 99 ppb) were maintained in open-top chambers over the growing season. All treatments were irrigated. Leaf, stem and pod weights and leaf area were measured weekly throughout the season. Total incident solar radiation and total radiation transmission through the canopy were measured with tube solarimeters and electronic integrating devices. Increased O3 concentrations were accompanied by depressed leaf area expansion and earlier leaf senescence, but did not affect total light interception over the entire season. Utilization efficiency (?) was reduced in high O3 treatments and was the most important factor in the reduction of yield; ? for the whole season declined from 0.89 g MJ?1 in the 30-ppb treatment to a low of 0.68 g MJ?1 in the 99-ppb treatment. Efficiencies were higher during reproductive than vegetative growth, but were not more sensitive to O3. Seed yield decreased from 450 g m?2 in the 30-ppb treatment to 320 g m?2 in the 99-ppb treatment. Fractional allocation of aboveground dry weight to seed was not affected by O3. Reduced ? values with increasing O3 concentrations were consistent with an earlier study by Unsworth et al. however, ? values for the vegetative phase of growth in this study were lower at all O3 concentrations. Lower ? values were attributed to canopy light saturation because of higher incident radiation and water stress caused by a shallow rooting zone during a hot, dry growing season. (author)

  18. Analysis of the effects of combustion emissions and Santa Ana winds on ambient ozone during the October 2007 southern California wildfires

    Science.gov (United States)

    Bytnerowicz, Andrzej; Cayan, Dan; Riggan, Philip; Schilling, Susan; Dawson, Philip; Tyree, Mary; Wolden, Lynn; Tissell, Robert; Preisler, Haiganoush

    2010-02-01

    Combustion emissions and strong Santa Ana winds had pronounced effects on patterns and levels of ambient ozone (O 3) in southern California during the extensive wildland fires of October 2007. These changes are described in detail for a rural receptor site, the Santa Margarita Ecological Reserve, located among large fires in San Diego and Orange counties. In addition, O 3 changes are also described for several other air quality monitoring sites in the general area of the fires. During the first phase of the fires, strong, dry and hot northeasterly Santa Ana winds brought into the area clean continental air masses, which resulted in minimal diurnal O 3 fluctuations and a 72-h average concentration of 36.8 ppb. During the second phase of the fires, without Santa Ana winds present and air filled with smoke, daytime O 3 concentrations steadily increased and reached 95.2 ppb while the lowest nighttime levels returned to ˜0 ppb. During that period the 8-h daytime average O 3 concentration reached 78.3 ppb, which exceeded the federal standard of 75 ppb. After six days of fires, O 3 diurnal concentrations returned to pre-fire patterns and levels.

  19. Evaluation and calibration of Aeroqual series 500 portable gas sensors for accurate measurement of ambient ozone and nitrogen dioxide

    Science.gov (United States)

    Lin, C.; Gillespie, J.; Schuder, M. D.; Duberstein, W.; Beverland, I. J.; Heal, M. R.

    2015-01-01

    Low-power, and relatively low-cost, gas sensors have potential to improve understanding of intra-urban air pollution variation by enabling data capture over wider networks than is possible with 'traditional' reference analysers. We evaluated an Aeroqual Ltd. Series 500 semiconducting metal oxide O3 and an electrochemical NO2 sensor against UK national network reference analysers for more than 2 months at an urban background site in central Edinburgh. Hourly-average Aeroqual O3 sensor observations were highly correlated (R2 = 0.91) and of similar magnitude to observations from the UV-absorption reference O3 analyser. The Aeroqual NO2 sensor observations correlated poorly with the reference chemiluminescence NO2 analyser (R2 = 0.02), but the deviations between Aeroqual and reference analyser values ([NO2]Aeroq - [NO2]ref) were highly significantly correlated with concurrent Aeroqual O3 sensor observations [O3]Aeroq. This permitted effective linear calibration of the [NO2]Aeroq data, evaluated using 'hold out' subsets of the data (R2 ? 0.85). These field observations under temperate environmental conditions suggest that the Aeroqual Series 500 NO2 and O3 monitors have good potential to be useful ambient air monitoring instruments in urban environments provided that the O3 and NO2 gas sensors are calibrated against reference analysers and deployed in parallel.

  20. Growth of adult Norway spruce (Picea abies [L.] Karst.) and European beech (Fagus sylvatica L.) under free-air ozone fumigation.

    Science.gov (United States)

    Wipfler, P; Seifert, T; Heerdt, C; Werner, H; Pretzsch, H

    2005-11-01

    This study attempted to detect the impact of ozone on adult trees of Norway spruce ( Picea abies [L.] Karst.) and European beech ( Fagus sylvatica L.) in an experimental mixed stand in Southern Bavaria, Germany. The aim was to examine whether there is a decrease in growth when trees are exposed to higher than atmospheric concentrations of ozone. This exposure was put into effect using a free-air fumigation system at tree crown level. Growth analysis was carried out on a group of 47 spruce and 36 beech trees, where radial stem increment at breast height - a sensitive index for stress - was measured. The ozone monitoring system allowed values to be obtained for the accumulated ozone exposure (SUM00) of each individual tree, so that their radial increment over three years could be correlated with the corresponding ozone exposure for the same time period. Correlation and regression analysis were then carried out to test the influence of ozone on diameter increment. In both spruce and beech, the initial stem diameter was the most influential factor on radial increment in the following year. A linear model was applied, including the diameter of the preceding year and the ozone exposure of the current year as predicting factors. For spruce trees, a significant negative influence of ozone exposure was found. In contrast, no significant ozone effect on diameter increment of beech was detected. The effect of ozone stress on a large spruce tree can lead to a decrease in potential radial increment of 22 %. The results are discussed in relation to other stress factors such as drought and lack of light. PMID:16388464

  1. Ozone exposure induces the activation of leaf senescence-related processes and morphological and growth changes in seedlings of Mediterranean tree species

    Energy Technology Data Exchange (ETDEWEB)

    Ribas, Angela [CSIC-CEAB-CREAF Ecophysiology Unit, CREAF-Center for Ecological Research and Forestry Applications, Edifici C, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)]. E-mail: a.ribas@creaf.uab.es; Pen-tilde uelas, Josep [CSIC-CEAB-CREAF Ecophysiology Unit, CREAF-Center for Ecological Research and Forestry Applications, Edifici C, Universitat Autonoma de Barcelona, 08193 Bellaterra, Barcelona (Spain)]. E-mail: josep.penuelas@uab.es; Elvira, Susana [CIEMAT, Avd. Complutense 22, 28040 Madrid (Spain); Gimeno, Benjamin S. [CIEMAT, Avd. Complutense 22, 28040 Madrid (Spain)

    2005-03-01

    Four Mediterranean tree taxa, Quercus ilex subsp. ilex, Quercus ilex subsp. ballota, Olea europaea cv. vulgaris and Ceratonia siliqua, were exposed to different ozone (O{sub 3}) concentrations in open top chambers (OTCs) during 2 years. Three treatments were applied: charcoal-filtered air (CF), non-filtered air (NF) and non-filtered air plus 40 ppb{sub v} of O{sub 3} (NF+). The photochemical maximal efficiency, Fv/Fm, decreased in NF+ plants during the second year of exposure, especially during the most stressful Mediterranean seasons (winter and summer). An increase of {delta}{sup 13}C was found in three of the four studied species during the first year of exposure. This finding was only maintained in C. siliqua during the second year. Decreases in the chlorophyll content were detected during the first year of fumigations in all the species studied, but not during the second year. The NF+ treatment induced changes in foliar anatomical characteristics, especially in leaf mass per area (LMA) and spongy parenchyma thickness, which increased in some species. A reduction in N content and an increase in {delta}{sup 15}N were found in all species during the second year when exposed in the NF+ OTCs, suggesting a change in their retranslocation pattern linked to an acceleration of leaf senescence, as also indicated by the above mentioned biochemical and anatomical foliar changes. The two Q. ilex subspecies were the most sensitive species since the changes in N concentration, {delta}{sup 15}N, chlorophyll, leaf area, LMA and biomass occurred at ambient O{sub 3} concentrations. However, C. siliqua was the most responsive species (29% biomass reduction) when exposed to the NF+ treatment, followed by the two Q. ilex subspecies (14-20%) and O. europaea (no significant reduction). Ozone resistance of the latter species was linked to some plant traits such as chlorophyll concentrations, or spongy parenchyma thickness. - Ozone induces species-specific leaf senescence-related processes and morphological and growth changes in seedlings of Mediterranean tree species.

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

    International Nuclear Information System (INIS)

    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.

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

    Scientific Electronic Library Online (English)

    Vander, Mendonça; Nildo Antônio Arruda de, Abreu; Henrique Antunes de, Souza; Glauco Antônio, Teixeira; Oscar Mariano, Hafle; José Darlan, Ramos.

    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 es [...] quema 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. Abstract in english 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  5. Assessment of Protective Effect of Some Modern Agrochemicals against Ozone-Induced Stress in Sensitive Clover and Tobacco Cultivars.

    Science.gov (United States)

    Blum, Oleg; Didyk, Nataliya; Pavluchenko, Nataliya; Godzik, Barbara

    2011-01-01

    Some modern agrochemicals with antioxidant potential were tested for their protective effect against ozone injury using clover and tobacco ozone-sensitive cultivars as model plants subjected to ambient ozone at two sites (Kyiv city in Ukraine and Szarów village in Poland). All used agrochemicals showed partial protective effects against ozone injury on clover and tobacco. Conducted studies confirmed the effectiveness of modern fungicides belonging to strobilurin group as protectants of sensitive crops against ozone damage. The effectiveness of new growth regulators "Emistym C" and "Agrostymulin" was showed for the first time. Out of the studied agrochemicals, fungicide "Strobi" and natural growth regulator "Emistym C" demonstrated the best protective effects. These agrochemicals present promise for further studies of their possible utilization for enhancement of ozone tolerance of sensitive crops. PMID:21776257

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

    Directory of Open Access Journals (Sweden)

    H.-K. Kim

    2013-09-01

    Full Text Available Plant functional type (PFT distributions affect the results of biogenic emission modeling as well as O3 and PM simulations using chemistry-transport models (CTMs. This paper analyzes the variations of both surface biogenic VOC emissions and O3 concentrations due to changes in the PFT distributions in the Seoul Metropolitan Areas, Korea. Also, this paper attempts to provide important implications for biogenic emissions modeling studies for CTM simulations. MM5-MEGAN-SMOKE-CMAQ model simulations were implemented over the Seoul Metropolitan Areas in Korea to predict surface O3 concentrations for the period of 1 May to 31 June 2008. Starting from MEGAN biogenic emissions analysis with three different sources of PFT input data, US EPA CMAQ O3 simulation results were evaluated by surface O3 monitoring datasets and further considered on the basis of geospatial and statistical analyses. The three PFT datasets considered were "(1KORPFT", developed with a region specific vegetation database; (2 CDP, adopted from US NCAR; and (3 MODIS, reclassified from the NASA Terra and Aqua combined land cover products. Comparisons of MEGAN biogenic emission results with the three different PFT data showed that broadleaf trees (BT are the most significant contributor, followed by needleleaf trees (NT, shrub (SB, and herbaceous plants (HB to the total biogenic volatile organic compounds (BVOCs. In addition, isoprene from BT and terpene from NT were recognized as significant primary and secondary BVOC species in terms of BVOC emissions distributions and O3-forming potentials in the study domain. Multiple regression analyses with the different PFT data (δO3 vs. δPFTs suggest that KORPFT can provide reasonable information to the framework of MEGAN biogenic emissions modeling and CTM O3 predictions. Analyses of the CMAQ performance statistics suggest that deviations of BT areas can significantly affect CMAQ isoprene and O3 predictions. From further evaluations of the 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.

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

    Science.gov (United States)

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

    2014-07-01

    Plant functional type (PFT) distributions affect the results of biogenic emission modeling as well as O3 and particulate matter (PM) simulations using chemistry-transport models (CTMs). This paper analyzes the variations of both surface biogenic volatile organic compound (BVOC) emissions and O3 concentrations due to changes in the PFT distributions in the Seoul Metropolitan Areas, Korea. The Fifth-Generation NCAR/Pennsylvania State Meso-scale Model (MM5)/the Model of Emissions of Gases and Aerosols from Nature (MEGAN)/the Sparse Matrix Operator Kernel Emissions (SMOKE)/the Community Multiscale Air Quality (CMAQ) model simulations were implemented over the Seoul Metropolitan Areas in Korea to predict surface O3 concentrations for the period of 1 May to 31 June 2008. Starting from a performance check of CTM predictions, we consecutively assessed the effects of PFT area deviations on the MEGAN BVOC and CTM O3 predictions, and we further considered the basis of geospatial and statistical analyses. The three PFT data sets considered were (1) the Korean PFT, developed with Korea-specific vegetation database; (2) the CDP PFT, adopted from the community data portal (CDP) of US National Center for Atmospheric Research in the United States (NCAR); (3) MODIS PFT, reclassified from the NASA Terra and Aqua combined land cover products. Although the CMAQ performance check reveals that all of the three different PFT data sets are applicable choices for regulatory modeling practice, noticeable primary data (i.e., PFT and Leaf Area Index (LAI)) was observed to be missing in many geographic locations. Based on the assessed effect of such missing data on CMAQ O3 predictions, we found that this missing data can cause spatially increased bias in CMAQ O3. Thus, it must be resolved in the near future to obtain more accurate biogenic emission and chemistry transport modeling results. Comparisons of MEGAN biogenic emission results with the three different PFT data showed that broadleaf 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 (?O3 vs. ?PFTs) 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.

  8. Growth of Continental-Scale Metro-Agro-Plexes, Regional Ozone Pollution, and World Food Production

    Science.gov (United States)

    Chameides, W. L.; Kasibhatla, P. S.; Yienger, J.; Levy, H., II

    1994-04-01

    Three regions of the northern mid-latitudes, the continental-scale metro-agro-plexes, presently dominate global industrial and agricultural productivity. Although these regions cover only 23 percent of the Earth's continents, they account for most of the world's commercial energy consumption, fertilizer use, food-crop production, and food exports. They also account for more than half of the world's atmospheric nitrogen oxide (NO_x) emissions and, as a result, are prone to ground-level ozone (O_3) pollution during the summer months. On the basis of a global simulation of atmospheric reactive nitrogen compounds, it is estimated that about 10 to 35 percent of the world's grain production may occur in parts of these regions where ozone pollution may reduce crop yields. Exposure to yield-reducing ozone pollution may triple by 2025 if rising anthropogenic NO_x emissions are not abated.

  9. Effect of ambient temperature in neonate aspic vipers: growth, locomotor performance and defensive behaviors.

    Science.gov (United States)

    Aïdam, Aurélie; Michel, Catherine Louise; Bonnet, Xavier

    2013-07-01

    The impact of temperature during incubation and gestation has been tested in various reptiles; the postnatal period has been rarely investigated however. Three groups of newborn aspic vipers (Vipera aspis) were placed under contrasted thermal regimes during 7 months: (1) a cool 23°C constant regime, (2) a warm 28°C constant regime, and (3) an optimal regime with free-access to a wide range of temperatures. Later, all the snakes were placed under hibernation conditions (6°C) during 3 months. Finally all the snakes were placed in the optimal thermal regime during 2 additional months. The total duration of the experiment was of 12 months. Body mass and feeding rates were recorded weekly, body size was measured monthly. We also assessed locomotor performance and recorded several behavioral traits (e.g., defensive and predatory behaviors). As expected, snakes raised under cool temperatures exhibited low feeding rate, growth rate, body condition, and they exhibited poor locomotor performance; they also displayed marked defensive behaviors (e.g., high number of defensive bites) whilst hesitating during longer periods to bite a prey. Such behavioral effects were detected at the end of the experiment (i.e., 5 months after exposure to contrasted thermal treatments [3 months of hibernation plus 2 months of optimal regime]), revealing long term effects. Surprisingly, growth rate and locomotor performance were not different between the two other groups, warm constant 28°C versus optimal regimes (albeit several behavioral traits differed), suggesting that the access to a wide range of ambient temperatures was not a crucial factor. PMID:23580460

  10. Growth and antioxidant status of broilers fed supplemental lysine and pyridoxine under high ambient temperature.

    Science.gov (United States)

    Khakpour Irani, Farzaneh; Daneshyar, Mohsen; Najafi, Ramin

    2015-01-01

    Three levels of lysine (90, 100 and 110% of Ross requirement) and of pyridoxine (3, 6 and 9 mg kg(-1)) were used in a 3 × 3 factorial experiment to investigate the growth and blood antioxidant ability of broilers under high ambient temperature. None of the dietary supplements affected the weight gain during the starter and grower periods. Although no significant differences were detected between the treatments during the entire period, high lysine level fed birds had a lower weight gain. At any levels of pyridoxine, high lysine fed birds were lighter than others. Neither the lysine nor pyridoxine changed the feed intake or feed conversion ratio during the starter, grower and entire period. However there was no significant difference between the treatments for blood malondialdehyde (MDA) concentration, medium lysine fed birds had lower blood MDA than other ones. No significant effects on blood triglyceride, total protein and blood superoxide dismutase activity were indicated with addition of any lysine or pyridoxine level. Medium lysine fed birds had decreased blood glutathione peroxidase activity compared to the birds of other treatments. It was concluded that providing the proposed dietary lysine requirement of Ross strain during heat stress ensuring the best body weight gain and body antioxidant ability. Higher lysine level causes the retarded weight gain due to higher excretion of arginine from the body and consequently higher lipid peroxidation. PMID:26261713

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Lawson, T.; Craigon, J.; Black, C.R.; Colls, J.J.; Tulloch, A.-M.; Landon, G. [Nottingham Univ., School of Biosciences, Loughborough (United Kingdom)

    2001-07-01

    Potato (Solanum tuberosum cv. Bintje) was grown in open-top chambers under three carbon dioxide (ambient and seasonal mean concentrations of 550 and 680 {mu}mol mol{sup -1} CO{sub 2}) and two ozone concentrations (ambient and an 8 h day {sup -1} seasonal mean of 50 nmol mol{sup -1} O{sub 3}) 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 O{sub 3} reduced above-ground dry weight at final harvest by 8.4% (P<0.05), but did not affect tuber yields. There was no significant interaction between CO{sub 2} and O{sub 3} for any of the growth and yield variables examined. Non-destructive analyses revealed no significant effect of elevated CO{sub 2} 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<0.05) in the 550 {mu}mol mol{sup -1} CO{sub 2} treatment. Responses to 550 and 680 {mu}mol mol{sup -1} CO{sub 2} were not significantly different for most parameters examined, suggesting the existence of an upper limit to the beneficial influence of CO{sub 2} enrichment. Significant effects on the above-ground dry weight and tuber yield were no longer apparent at final harvest, although tuber numbers were increased (P<0.05) under elevated CO{sub 2}, particularly in the smaller size categories. The results show that the O{sub 3} treatment imposed was insufficient to reduce tuber yields and that, although elevated CO{sub 2} enhanced crop growth during the early stages of the season, this beneficial effect was not sustained to maturity. (Author)

  14. Growth response of four species of Eastern hardwood tree seedlings exposed to ozone, acidic precipitation, and sulfur dioxide

    International Nuclear Information System (INIS)

    In 1987 a study was conducted in controlled environment chambers to determine the foliar sensitivity of tree seedlings of eight species to ozone and acidic precipitation, and to determine the influence of leaf position on symptom severity. Jensen and Dochinger conducted concurrent similar studies in Continuously Stirred Tank Reactor (CSTR) chambers with ten species of forest trees. Based on the results of these initial studies, four species representing a range in foliar sensitivity to ozone were chosen: black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and yellow-poplar (Liriodendron tulipifera L.). These species were also chosen because of their ecological and/or commercial importance in Pennsylvania. Seedlings were exposed in growth chambers simulated acid rain. In addition acute exposures to sulfur dioxide were conducted in a regime based on unpublished monitoring data collected near coal-fired power plants. The objective of this study was to determine if the pollutant treatments influenced the growth and productivity of seedlings of these four species. This information will help researchers and foresters understand the role of air pollution in productivity of eastern forests

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

    International Nuclear Information System (INIS)

    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

  16. Growth of continental-scale metro-agro-plexes, regional ozone pollution, and world food production

    Energy Technology Data Exchange (ETDEWEB)

    Chameides, W.L.; Kasibhatla, P.S. (Georgia Institute of Technology, Atlanta, GA (United States)); Yienger, J.; Levy, H. II (Princeton Univ., NJ (United States))

    1994-04-01

    Three regions of the northern mid-latitudes, the continental-scale metro-agro-plexes, presently dominate global industrial and agricultural productivity. Although these regions cover only 23 percent of the Earth's continents, they account for most of the world's commercial energy consumption, fertilizer use, food-crop production, and food exports. They also account for more than half of the world's atmospheric nitrogen oxide (NO[sub x]) emissions and, as a result, are prone to ground-level ozone (O[sub 3]) pollution during the summer months. On the basis of a global simulation of atmospheric reactive nitrogen compounds, it is estimated that about 10 to 35 percent of the world's grain production may occur in parts of these regions where ozone pollution may reduce crop yields. Exposure to yield-reducing ozone pollution may triple by 2025 if rising anthropogenic NO[sub x] emissions are not abated.

  17. Clone and soil effects on the growth of young Norway spruce during 14 months exposure to ozone plus acid mist.

    Science.gov (United States)

    Payer, H D; Pfirrmann, T; Kloos, M; Blank, L W

    1990-01-01

    Five clones of 3-year old Norway spruce (Picea abies [L.] Karst), planted in a soil from the Bavarian Forest (pH 4.4) or a soil from the Calcareous Bavarian Alps (pH 6.9), were exposed for two successive vegetation periods, in closed environmental chambers, to a pollution treatment consisting of acidic mist (pH 3.0) plus ozone levels of 100 microg m(-3) with episodes of 130-360 microg m(-3); control trees were exposed to mist of pH 5.6 and ozone levels of 50 microg m(-3). Climatic and pollution protocols followed the diurnal and seasonal pattern characteristic for the Inner Bavarian Forest in Southern Germany, an area affected by the new-type forest decline. Biometric parameters were strongly related to clone and soil. Pollution treatment had a limited effect on only a few growth parameters. The stem diameter growth increment of two clones was reduced by pollution treatment in both soils, a third clone was affected in the acidic soil only. Two other clones were not affected at all. Stem volume increment of three clones, calculated as D(2)H, was reduced by pollution treatment in the neutral soil, a fourth clone was affected in the acidic soil only. Bud break was either delayed (two clones) or accelerated (two other clones) by treatment. Depending on soil and clone, needle yellowing was observed in previous years' needles in both treatment and control trees exposed to increased light intensities. The 'spotted' yellowing was not identical to symptoms found in forest decline areas and was most likely a consequence of nutrient deficiencies during the vegetation period preceding the experiment. The results of this experiment are discussed with regard to field observations and forest productivity. The complex pattern of growth responses resulting from interactions between air pollution, soil and genetic factors is considered to reflect different susceptibilities of trees to air pollutants. PMID:15092281

  18. Measurement of Ozone Production Sensor

    Directory of Open Access Journals (Sweden)

    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.

  19. Elevated carbon dioxide and ozone effects on above- and belowground growth and decomposition in a no-till soybean-wheat system

    Science.gov (United States)

    Elevated atmospheric carbon dioxide and ozone concentrations often have counteracting influences on many C3 crops depending on the concentration of the gases and sensitivity of the crop although root growth and residue decomposition responses are poorly understood. The objective of this experiment w...

  20. 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

    International Nuclear Information System (INIS)

    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

  1. Bioassaying for ozone with pollen systems.

    OpenAIRE

    Feder, W A

    1981-01-01

    Sensitivity to ozone of pollen germinating in vitro is closely correlated with ozone sensitivity of the pollen parent. Ozone-sensitive and tolerant pollen populations have been identified in tobacco, petunia, and tomato cultivars. The rate of tube elongation can be reversibly slowed or stopped by exposure to low concentrations of ozone. Tube growth rates in the presence of a range of ozone dosages, of pollen populations exhibiting differing ozone sensitivity can be measured and different grow...

  2. Plant phenology, growth and nutritive quality of Briza maxima: responses induced by enhanced ozone atmospheric levels and nitrogen enrichment.

    Science.gov (United States)

    Sanz, J; Bermejo, V; Muntifering, R; González-Fernández, I; Gimeno, B S; Elvira, S; Alonso, R

    2011-02-01

    An assessment of the effects of tropospheric ozone (O(3)) levels and substrate nitrogen (N) supplementation, singly and in combination, on phenology, growth and nutritive quality of Briza maxima was carried out. Two serial experiments were developed in Open-Top Chambers (OTC) using three O(3) and three N levels. Increased O(3) exposure did not affect the biomass-related parameters, but enhanced senescence, increased fiber foliar content (especially lignin concentration) and reduced plant life span; these effects were related to senescence acceleration induced by the pollutant. Added N increased plant biomass production and improved nutritive quality by decreasing foliar fiber concentration. Interestingly, the effects of N supplementation depended on meteorological conditions and plant physiological activity. N supplementation counteracted the O(3)-induced senescence but did not modify the effects on nutritive quality. Nutritive quality and phenology should be considered in new definitions of the O(3) limits for the protection of herbaceous vegetation. PMID:21111519

  3. Enhancement of growth, photosynthetic performance and yield by exclusion of ambient UV components in C3 and C4 plants.

    Science.gov (United States)

    Kataria, Sunita; Guruprasad, K N; Ahuja, Sumedha; Singh, Bupinder

    2013-10-01

    A field experiment was conducted under tropical climate for assessing the effect of ambient UV-B and UV-A by exclusion of UV components on the growth, photosynthetic performance and yield of C3 (cotton, wheat) and C4 (amaranthus, sorghum) plants. The plants were grown in specially designed UV exclusion chambers, wrapped with filters that excluded UV-B (total biomass accumulation and yield. Measurements of the chlorophyll, chlorophyll fluorescence parameters, gas exchange parameters and the activity of Ribulose-1,5-bisphosphate carboxylase (Rubisco) by fixation of (14)CO2 indicated a direct relationship between enhanced rate of photosynthesis and yield of the plants. Quantum yield of electron transport was enhanced by the exclusion of UV indicating better utilization of PAR assimilation and enhancement in reducing power in all the four plant species. Exclusion of UV-B in particular significantly enhanced the net photosynthetic rate, stomatal conductance and activity of Rubisco. Additional fixation of carbon due to exclusion of ambient UV-B was channeled towards yield as there was a decrease in the level of UV-B absorbing substances and an increase in soluble proteins in all the four plant species. The magnitude of the promotion in all the parameters studied was higher in dicots (cotton, amaranthus) compared to monocots (wheat, sorghum) after UV exclusion. The results indicated a suppressive action of ambient UV-B on growth and photosynthesis; dicots were more sensitive than monocots in this suppression while no great difference in sensitivity was found between C3 and C4 plants. Experiments indicated the suppressive action of ambient UV on carbon fixation and yield of C3 and C4 plants. Exclusion of solar UV-B will have agricultural benefits in both C3 and C4 plants under tropical climate. PMID:24041852

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

    International Nuclear Information System (INIS)

    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 ?-In2Se3 nanosheets was firstly reported by this submission

  5. Effect of Ozone and Simulated Acid Rain on Growth, Nitrogen Fixation and Peroxidase Activity in Faba Bean (Vicia faba L.) Plant

    OpenAIRE

    Laila Ezzel-Arab Abdel Nasser

    2002-01-01

    Faba beans (Vicia faba L. CV. Giza 400) were exposed to ozone (100 ppb) and simulated acid rain (SAR) at pH 3, separately and combined over 2-weaks period while grown in climate controlled growth chambers. Ozone fumigation (O3) exposure was for 5 h day -1, whereas acid rain exposure was for 2 h per week. The results showed that exposure to high O3 concentration (100 ppb) decreased the number and weight of root nodules, suppressed nitrogenase activity and strongly induce...

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

    International Nuclear Information System (INIS)

    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 ?W/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 ?W/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)

  7. Plant phenology, growth and nutritive quality of Briza maxima: Responses induced by enhanced ozone atmospheric levels and nitrogen enrichment

    International Nuclear Information System (INIS)

    An assessment of the effects of tropospheric ozone (O3) levels and substrate nitrogen (N) supplementation, singly and in combination, on phenology, growth and nutritive quality of Briza maxima was carried out. Two serial experiments were developed in Open-Top Chambers (OTC) using three O3 and three N levels. Increased O3 exposure did not affect the biomass-related parameters, but enhanced senescence, increased fiber foliar content (especially lignin concentration) and reduced plant life span; these effects were related to senescence acceleration induced by the pollutant. Added N increased plant biomass production and improved nutritive quality by decreasing foliar fiber concentration. Interestingly, the effects of N supplementation depended on meteorological conditions and plant physiological activity. N supplementation counteracted the O3-induced senescence but did not modifiy the effects on nutritive quality. Nutritive quality and phenology should be considered in new definitions of the O3 limits for the protection of herbaceous vegetation. - Research highlights: ? Forage quality (foliar protein and fiber content) and phenology are more O3-sensitive than growth parameters in the Mediterranean annual grass Briza maxima. ? The effects of N supplementation depended on meteorological conditions and plant physiological activity. ? Increase in nitrogen supplementation counterbalanced the O3-induced increase in senescence biomass. ? Nutritive quality and phenology should be considered in new definitions of the O3 limits for the protection of natural herbaceous vegetation. - Forage quality and phenology are more O3-sensitive than growth parameters in the Mediterranean annual grass Briza maxima.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    DEFF Research Database (Denmark)

    Chen, Xiaoying; Song, Fengbin; Liu, Fulai; Tian, Chunjie; Liu, Shengqun; Xu, Hongwen; Zhu, Xiancan

    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 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...

  10. 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

    Science.gov (United States)

    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...

  11. Effect of ambient gas pressure on pulsed laser ablation plume dynamics and ZnTe film growth

    Energy Technology Data Exchange (ETDEWEB)

    Rouleau, C.M.; Lowndes, D.H.; Geohegan, D.B.; Allard, L.F. [Oak Ridge National Lab., TN (United States); Strauss, M.A.; Cao, S.; Pedraza, A.J. [Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering; Puretzky, A.A. [Inst. of Spectroscopy, Troitsk (Russian Federation)

    1995-12-01

    Epitaxial thin films of nitrogen-doped p-ZnTe were grown on single-crystal, semi-insulating Ga-As substrates via pulsed laser ablation of a stoichiometric ZnTe target. Both low pressure nitrogen ambients and high vacuum were used. Results of in situ reflection high energy electron diffraction (RHEED) and time-resolved ion probe measurements have been compared with ex situ Hall effect and transmission electron microscopy (TEM) measurements. A strong correlation was observed between the nature of the film`s surface during growth (2-D vs. 3-D, assessed via RHEED) and the ambient gas pressures employed during deposition. The extended defect content (assessed via cross-sectional TEM) in the region >150 mn from the film/substrate interface was found to increase with the ambient gas pressure during deposition, which could not be explained by lattice mismatch alone. At sufficiently high pressures, misoriented, columnar grains developed which were not only consistent with the RHEED observations but also were correlated with a marked decrease in Hall mobility and a slight decrease in hole concentration. Ion probe measurements, which monitored the attenuation and slowing of the ion current arriving at the substrate surface, indicated that for increasing nitrogen pressure the fast (vacuum) velocity distribution splits into a distinct fast and two collisionally-slowed components or modes. Gas controlled variations in these components mirrored trends in electrical properties and microstructural measurements.

  12. 40 CFR 52.977 - Control strategy and regulations: Ozone.

    Science.gov (United States)

    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...

  13. Chronic exposure of Rutilus rutilus caspicus fingerlings to ambient copper: Effects on food intake, growth performance, biochemistry and stress resistance.

    Science.gov (United States)

    Hoseini, Seyyed Morteza; Rajabiesterabadi, Hamid; Kordrostami, Sara

    2016-02-01

    An 8-week trial was conducted to investigate the effect of ambient copper (Cu) on growth performance, physiological characteristics and stress resistance of Caspian roach, Rutilus rutilus caspicus. Fish were exposed to 0 (control), 0.02, 0.04 and 0.06 ppm Cu, and their food intake and growth performance were fortnightly recorded. Also, serum cortisol, glucose, alanine aminotransferase (ALT) and sodium (Na) levels were determined after 2 and 8 weeks exposure to ambient Cu. At the end of trial, serum total protein, albumin, globulin and albumin-globulin ratio (A:G) levels, whole body proximate composition and stress tolerance of the fish were measured. Results showed that Cu exposure resulted in a significant suppression in food intake after 2 weeks, which was eliminated after 4 weeks in 0.02 ppm groups and after 6 weeks in 0.04 and 0.06 ppm groups. Cu exposure brought about an inferior growth that recovered in line with the experiment progression, following a dose-dependent manner. Cu-exposed fish showed a dose-dependent increase in serum cortisol, glucose and ALT as well as decrease in serum Na, after 2 weeks. These parameters showed a full recovery in 0.02 ppm group and a partial recovery in 0.04 and 0.06 ppm groups, at the 8th week. Significant suppression in serum total protein, albumin, globulin and A:G levels and whole body dry matter, lipid and protein levels as well as stress resistance was observed in 0.04 and 0.06 ppm groups. It is concluded that Cu exposure could adversely affect growth performance, physiological characteristics and stress resistance of Caspian roach, which might affect its ecological features. PMID:24105068

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

    OpenAIRE

    Chatani, S.; Amann, M.; Goel, A.; Hao, J.; Klimont, Z.; Kumar, A.; Mishra, A.; Sharma, S.; 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...

  15. Plant resistance mechanisms to air pollutants: rhythms in ascorbic acid production during growth under ozone stress

    Energy Technology Data Exchange (ETDEWEB)

    Lee, E.H. (Climate Stress Laboratory, USDA, ARS, Beltsville, MD (United States))

    1991-01-01

    Relationships between ozone (O3) tolerance and leaf ascorbic acid concentrations in O3-susceptible (O3-S) 'Hark' and O3-resistant (O3-R) 'Hood' soybean, Glycine max (L.) Merr., cultivars were examined with high-performance liquid chromatography (HPLC). Leaf samples were analyzed at 4 intervals during a 24 h period. Soybean cultivars grown in the greenhouse with charcoal filtered (CF) and nonfiltered (NF) air showed daily oscillations in ascorbic acid production. Highest ascorbic acid levels in leaves during light coincided with highest concentrations of photochemical oxidants in the atmosphere at 2:00 p.m. The resistant genotype produced more ascorbic acid in its trifoliate leaves than did the corresponding susceptible genotype. Under CF air (an O3-reduced environment) O3-S and O3-R cultivars showed rhythms in ascorbic acid production. In NF air (an O3 stress environment) the O3-R cultivar alone showed rhythms in ascorbic acid production. Results indicated that superior O3 tolerance in the Hood soybean cultivar (compared with Hark) was associated with a greater increase in endogenous levels of ascorbic acid. Ascorbic acid may scavenge free radicals and thereby protect cells from injury by O3 or other oxyradical products. Plants defend themselves against photochemical oxidant stress, such as O3, by several mechanisms. Experimental evidence indicates that antioxidant defense systems existing in plant tissues may function to protect cellular components from deleterious effects of photochemical oxidants through endogenous and exogenous controls.

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

    Science.gov (United States)

    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).

  17. Chronic ozone exacerbates the reduction in photosynthesis and acceleration of senescence caused by limited N availability in Nicotiana sylvestris

    Science.gov (United States)

    Elevated ozone (O3) and limiting soil nitrogen (N) availability both negatively affect crop performance. However, little is known about how the combination of elevated O3 and limiting N affect crop growth and metabolism. In this study, we grew tobacco (Nicotiana sylvestris) in ambient and elevated O...

  18. Biaxial Fatigue Crack Growth Behavior in Aluminum Alloy 5083-H116 Under Ambient Laboratory and Saltwater Environments

    Science.gov (United States)

    Perel, V. Y.; Misak, H. E.; Mall, S.; Jain, V. K.

    2015-04-01

    Crack growth of aluminum alloy 5083 was investigated when subjected to the in-plane biaxial tension-tension fatigue with stress ratio of 0.5 under ambient laboratory and saltwater environments. Cruciform specimens with a center hole, containing a notch and precrack at 45° to the specimen's arms, were tested in a biaxial fatigue test machine. Two biaxiality ratios, ? = 1 and ? = 1.5, were studied. For ? = 1, crack propagated along a straight line collinearly with the precrack, while for ? = 1.5 case, the crack path was curved and non-collinear with the precrack. Uniaxial fatigue tests were also conducted. Crack growth rates were faster under the biaxiality fatigue in comparison to uniaxial fatigue at a given crack driving force (? K I or ? G) in both environments. Further, an increase in biaxiality ratio increased the crack growth rate, i.e., faster for ? = 1.5 case than ? = 1 case. Both biaxial fatigue and saltwater environment showed detrimental effects on the fatigue crack growth resistance of 5083, and its combination is highly detrimental when compared to uniaxial fatigue.

  19. Plant phenology, growth and nutritive quality of Briza maxima: Responses induced by enhanced ozone atmospheric levels and nitrogen enrichment

    Energy Technology Data Exchange (ETDEWEB)

    Sanz, J., E-mail: j.sanz@ciemat.e [Ecotoxicity of Atmospheric Pollutants, CIEMAT, Avda, Complutense 22, 28040 Madrid (Spain); Bermejo, V., E-mail: victoria.bermejo@ciemat.e [Ecotoxicity of Atmospheric Pollutants, CIEMAT, Avda, Complutense 22, 28040 Madrid (Spain); Muntifering, R., E-mail: muntirb@auburn.ed [Department of Animal Sciences, Auburn University, Auburn, AL 36849 (United States); Gonzalez-Fernandez, I., E-mail: ignacio.gonzalez@ciemat.e [Ecotoxicity of Atmospheric Pollutants, CIEMAT, Avda, Complutense 22, 28040 Madrid (Spain); Gimeno, B.S., E-mail: benjamin.gimeno@ciemat.e [Ecotoxicity of Atmospheric Pollutants, CIEMAT, Avda, Complutense 22, 28040 Madrid (Spain); Elvira, S., E-mail: susana.elvira@ciemat.e [Ecotoxicity of Atmospheric Pollutants, CIEMAT, Avda, Complutense 22, 28040 Madrid (Spain); Alonso, R., E-mail: rocio.alonso@ciemat.e [Ecotoxicity of Atmospheric Pollutants, CIEMAT, Avda, Complutense 22, 28040 Madrid (Spain)

    2011-02-15

    An assessment of the effects of tropospheric ozone (O{sub 3}) levels and substrate nitrogen (N) supplementation, singly and in combination, on phenology, growth and nutritive quality of Briza maxima was carried out. Two serial experiments were developed in Open-Top Chambers (OTC) using three O{sub 3} and three N levels. Increased O{sub 3} exposure did not affect the biomass-related parameters, but enhanced senescence, increased fiber foliar content (especially lignin concentration) and reduced plant life span; these effects were related to senescence acceleration induced by the pollutant. Added N increased plant biomass production and improved nutritive quality by decreasing foliar fiber concentration. Interestingly, the effects of N supplementation depended on meteorological conditions and plant physiological activity. N supplementation counteracted the O{sub 3}-induced senescence but did not modifiy the effects on nutritive quality. Nutritive quality and phenology should be considered in new definitions of the O{sub 3} limits for the protection of herbaceous vegetation. - Research highlights: Forage quality (foliar protein and fiber content) and phenology are more O{sub 3}-sensitive than growth parameters in the Mediterranean annual grass Briza maxima. The effects of N supplementation depended on meteorological conditions and plant physiological activity. Increase in nitrogen supplementation counterbalanced the O{sub 3}-induced increase in senescence biomass. Nutritive quality and phenology should be considered in new definitions of the O{sub 3} limits for the protection of natural herbaceous vegetation. - Forage quality and phenology are more O{sub 3}-sensitive than growth parameters in the Mediterranean annual grass Briza maxima.

  20. Long-term prediction of fish growth under varying ambient temperature using a multiscale dynamic model

    Directory of Open Access Journals (Sweden)

    Radde Nicole

    2009-11-01

    Full Text Available Abstract Background Feed composition has a large impact on the growth of animals, particularly marine fish. We have developed a quantitative dynamic model that can predict the growth and body composition of marine fish for a given feed composition over a timespan of several months. The model takes into consideration the effects of environmental factors, particularly temperature, on growth, and it incorporates detailed kinetics describing the main metabolic processes (protein, lipid, and central metabolism known to play major roles in growth and body composition. Results For validation, we compared our model's predictions with the results of several experimental studies. We showed that the model gives reliable predictions of growth, nutrient utilization (including amino acid retention, and body composition over a timespan of several months, longer than most of the previously developed predictive models. Conclusion We demonstrate that, despite the difficulties involved, multiscale models in biology can yield reasonable and useful results. The model predictions are reliable over several timescales and in the presence of strong temperature fluctuations, which are crucial factors for modeling marine organism growth. The model provides important improvements over existing models.

  1. Quantitative constraints on the 17O-excess (?17O) signature of surface ozone: Ambient measurements from 50°N to 50°S using the nitrite-coated filter technique

    Science.gov (United States)

    Vicars, William C.; Savarino, Joël

    2014-06-01

    The unique and distinctive 17O-excess (?17O) of ozone (O3) provides a conservative tracer for oxidative processes in both modern and paleo-atmospheres and has acted as the primary driver of theoretical and experimental research into non-mass-dependent fractionation (NMDF) for over three decades. However, due to the inherent complexity of extracting O3 from ambient air, the existing observational dataset for tropospheric O3 isotopic composition remains quite small. Recent analytical developments have provided a robust and reliable means for determining ?17O(O3)trans., the transferrable ?17O signature of ozone in the troposphere (Vicars et al., 2012). We have employed this new methodology in a systematic investigation of the spatial and seasonal features of ?17O(O3)trans. in two separate field campaigns: a weekly sampling effort at our laboratory in Grenoble, France (45°N) throughout 2012 (n = 47) and a four-week campaign onboard the Research Vessel (R/V) Polarstern along a latitudinal transect from 50°S to 50°N in the Atlantic Ocean (n = 30). The bulk 17O-excess of ozone, denoted ?17O(O3)bulk, exhibited mean (±1?) values of 26.2 ± 1.3‰ (?17O(O3)trans. = 39.3 ± 2.0‰) and 25.9 ± 1.1‰ (?17O(O3)trans. = 38.8 ± 1.6‰) for the Grenoble and R/V Polarstern collections, respectively. This range of values is in excellent quantitative agreement with the two previous studies of ozone triple-isotope composition, which have yielded mean (±1?) ?17O(O3)bulk values of 25.4 ± 9.0‰ (n = 89). However, the magnitude of variability detected in the present study is much smaller than that formerly reported. In fact, the standard deviation of ?17O(O3)bulk in each new dataset is lower than the uncertainty previously estimated for the filter technique (±1.7‰), indicating a low level of natural spatial and temporal variation in the 17O-excess of surface ozone. For instance, no clear temporal pattern in ?17O(O3) is evident in the annual record from Grenoble despite dramatic seasonal variations in ozone and atmospheric reactive nitrogen (NOx = NO + NO2) concentrations. However, a small but statistically significant difference is distinguishable in the R/V Polarstern record when comparing samples collected in the Southern and Northern Hemispheres, which possessed average ?17O(O3)bulk values of 25.2 ± 1.0‰ and 26.5 ± 0.7‰, respectively. The implications of these results are discussed in the context of the tropospheric ozone budget and the use of oxygen isotope ratios of secondary atmospheric species to derive information regarding oxidation pathways from modern and paleo-atmospheres.

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

    International Nuclear Information System (INIS)

    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

  3. Effects of ozone exposures on epicuticular wax of ponderosa pine needles

    International Nuclear Information System (INIS)

    Two-year-old ponderosa pine (Pinus ponderosa L.) seedlings were exposed during the 1989 and 1990 growing seasons to ozone in open-top chambers placed in a forested location at Shirley Meadow, Greenhorn Mountain Range, Sierra Nevada. The ozone treatments were as follows: charcoal-filtered air (CF); charcoal-filtered air with addition of ambient concentrations of ozone (CF + O3); and charcoal-filtered air with addition of doubled concentrations of ozone (CF + 2 x O3). Ozone effects on ponderosa pine seedlings progressed and accumulated over two seasons of exposure. Throughout the first season, increased visible injury and accelerated senescence of the foliage were noted. Subsequently, during the second season of ozone exposure, various physiological and biochemical changes in the foliage took place. All these changes led to reduced growth and biomass of the seedlings. Epistomatal waxes of needles from the CA + 2 x O3 treatment had an occluded appearance. This phenomenon may be caused by earlier phenological development of needles from the high-ozone treatments and disturbed development and synthesis of waxes. It may also be caused by chemical degradation of waxes by exposures to high ozone concentrations. (orig.)

  4. Five years of growth of soybean at elevated CO2 and ozone, an overview

    Science.gov (United States)

    SoyFACE is the first FACE experiment to focus on a seed legume and on corn and the first to explore the interactions of both e[CO2] and e[O3] on the growth and development of an arable crop. The intent of the SoyFACE experiment is to orchestrate a coordinated and comprehensive investigation of the i...

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

    International Nuclear Information System (INIS)

    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)

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

    Directory of Open Access Journals (Sweden)

    T. Petäjä

    2005-01-01

    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 sulphur 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Foliar injury, leaf gas exchange and biomass responses of black cherry (Prunus serotina Ehrh.) half-sibling families to ozone exposure.

    Science.gov (United States)

    Kouterick, K B; Skelly, J M; Fredericksen, T S; Steiner, K C; Kolb, T E; Ferdinand, J A

    2000-01-01

    Open pollinated families of black cherry seedlings were studied to determine genotypic differences in foliar ozone injury and leaf gas exchange in 1994 and growth response following three growing seasons. An O(3)-sensitive half-sibling family (R-12) and an O(3)-tolerant half-sibling family (MO-7) planted in natural soil were studied along with generic nursery stock (NS) seedlings. Ozone exposure treatments were provided through open top chambers and consisted of 50, 75, and 97% of ambient ozone, and open plots from May 9 to August 26, 1994. Ambient ozone concentrations reached an hourly peak of 88 ppb with 7-hour averages ranging from 39 to 46 ppb. Seedlings in the 50 and 75% of ambient chambers were never exposed to greater than 80 ppb O(3). Visible foliar ozone injury (stipple) was significantly higher for R-12 seedlings than MO-7 seedlings and increased with increasing ozone exposures. For the chamber treatments averaged over all families, there was no significant difference in stomatal conductance and net photosynthetic rates, but there was a significant decrease in root biomass, and a significant decrease in root/shoot ratio between the 50 and 97% of ambient chambers. Stomatal conductance and net photosynthetic rates were significantly different between families with R-12 seedlings generally greater than MO-7 seedlings. The R-12 seedlings had a 7.5 mmol m(-2) increase in ozone uptake compared to MO-7, and at the same cumulative O(3) exposure R-12 exhibited 40.9% stippled leaf area, whereas MO-7 had 9.2% stippled leaf area. Significant differences were observed in stem volume growth and total final biomass between the open-top chambers and open plots. Although R-12 had the most severe foliar ozone injury, this family had significantly greater stem volume growth and total final biomass than MO-7 and NS seedlings. Root:shoot ratio was not significantly different between MO-7 and R-12 seedlings. PMID:15093015

  9. Ozone co-exposure modifies cardiac responses to fine and ultrafine ambient particulate matter in mice: concordance of electrocardiogram and mechanical responses

    Science.gov (United States)

    BackgroundStudies have shown a relationship between air pollution and increased risk of cardiovascular morbidity and mortality. Due to the complexity of ambient air pollution composition, recent studies have examined the effects of co-exposure, particularly particulate matter (PM...

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

    International Nuclear Information System (INIS)

    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

  11. Exposure-Relevant Ozone Chemistry in Occupied Spaces

    Energy Technology Data Exchange (ETDEWEB)

    Coleman, Beverly Kaye

    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 byproduct yield) were explored. In Chapter 5, the reaction of ozone with permethrin, a residual insecticide used in aircraft cabins, to form phosgene is investigated. A derivatization technique was developed to detect phosgene at low levels, and chamber experiments were conducted with permethrin-coated cabin materials. It was determined that phosgene formation, if it occurs in the aircraft cabin, is not likely to exceed the relevant, health-based phosgene exposure guidelines.

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

    OpenAIRE

    Chatani, S.; Amann, M.; Goel, A.; Hao, J.; Klimont, Z.; Kumar, A.; Mishra, A.; Sharma, S.; 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...

  13. Crescimento de Aegla manuinflata (Decapoda, Anomura, Aeglidae) em ambiente natural / Growth of Aegla manuinflata (Decapoda, Anomura, Aeglidae) in natural environment

    Scientific Electronic Library Online (English)

    André, Trevisan; Sandro, Santos.

    2011-12-01

    Full Text Available O presente trabalho teve como objetivo avaliar o crescimento de Aegla manuinflata Bond-Buckup & Santos, 2009 em ambiente natural. Para isso foram realizadas coletas mensais de abril de 2006 a maio de 2007 no arroio Passo Taquara, no município de São Pedro do Sul, Rio Grande do Sul, Brasil. Os organi [...] smos foram coletados utilizando armadilhas plásticas e puçá. Os espécimes foram sexados e tiveram mensurado o comprimento do cefalotórax (CC), em seguida foram devolvidos ao córrego. O crescimento foi avaliado utilizando o modelo de von Bertalanffy. As curvas de crescimento do cefalotórax, estimadas para machos e fêmeas, são descritas pelas seguintes equações Ct = 28,00 [1 - e-0,0047(t+10,63)] e Ct = 25,16 [1 - e-0,0051(t+17,65)], respectivamente. Os machos atingem tamanhos maiores que as fêmeas. A longevidade foi estimada em três anos para os machos e dois anos e meio para as fêmeas. Abstract in english The aim of this work was to evaluate the growth of Aegla manuinflata Bond-Buckup & Santos, 2009 in natural environment. Samplings were monthly performed, from April/2006 to May/2007, in a tributary of Ibicuí-Mirim River, which belongs to the Uruguay River basin, at São Pedro do Sul municipality, sta [...] te of Rio Grande do Sul, Brazil. Traps and dip nets were used to collect the animals. The specimens were sexed and had their cephalothoracic length (CL) measured, using a digital caliper with 0.01 mm precision. The growth was evaluated using the von Bertalanffy model. The growth curves in length (mm), for the data obtained through the modal progression, are described by the equations: Ct = 28.00 [1 - e-0.0047(t+10.63)] for males and Ct = 25.16 [1 - e-0.0051(t+17.65)] for females. The maximum estimated age for males was three years and for females was two years and six months.

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

    International Nuclear Information System (INIS)

    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 ?e[O2] = 3.2 x 10-16 cm2 and ?e[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 ?i-Ar = 2.1 x 10-16 cm2 and ion-oxygen ?i-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

  15. Regional assessment of ozone sensitive tree species using bioindicator plants.

    Science.gov (United States)

    Coulston, John W; Smith, Gretchen C; Smith, William D

    2003-04-01

    Tropospheric ozone occurs at phytotoxic levels in the northeastern and mid-Atlantic regions of the United States. Quantifying possible regional-scale impacts of ambient ozone on forest tree species is difficult and is confounded by other factors, such as moisture and light, which influence the uptake of ozone by plants. Biomonitoring provides an approach to document direct foliar injury irrespective of direct measure of ozone uptake. We used bioindicator and field plot data from the USDA Forest Service to identify tree species likely to exhibit regional-scale ozone impacts. Approximately 24% of sampled sweetgum (Liquidambar styraciflua), 15% of sampled loblolly pine (Pinus taeda), and 12% of sampled black cherry (Prunus serotina) trees were in the highest risk category. Sweetgum and loblolly pine trees were at risk on the coastal plain of Maryland, Virginia and Delaware. Black cherry trees were at risk on the Allegheny Plateau (Pennsylvania), in the Allegheny Mountains (Pennsylvania, West Virginia, and Maryland) as well as coastal plain areas of Maryland and Virginia. Our findings indicate a need for more in-depth study of actual impacts on growth and reproduction of these three species. PMID:12691526

  16. 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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. N-fixation in legumes - An assessment of the potential threat posed by ozone pollution.

    Science.gov (United States)

    Hewitt, D K L; Mills, G; Hayes, F; Norris, D; Coyle, M; Wilkinson, S; Davies, W

    2016-01-01

    The growth, development and functioning of legumes are often significantly affected by exposure to tropospheric ozone (O3) pollution. However, surprisingly little is known about how leguminous Nitrogen (N) fixation responds to ozone, with a scarcity of studies addressing this question in detail. In the last decade, ozone impacts on N-fixation in soybean, cowpea, mung bean, peanut and clover have been shown for concentrations which are now commonly recorded in ambient air or are likely to occur in the near future. We provide a synthesis of the existing literature addressing this issue, and also explore the effects that may occur on an agroecosystem scale by predicting reductions in Trifolium (clovers) root nodule biomass in United Kingdom (UK) pasture based on ozone concentration data for a "high" (2006) and "average" ozone year (2008). Median 8% and 5% reductions in clover root nodule biomass in pasture across the UK were predicted for 2006 and 2008 respectively. Seasonal exposure to elevated ozone, or short-term acute concentrations >100 ppb, are sufficient to reduce N-fixation and/or impact nodulation, in a range of globally-important legumes. However, an increasing global burden of CO2, the use of artificial fertiliser, and reactive N-pollution may partially mitigate impacts of ozone on N-fixation. PMID:26385644

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

    Science.gov (United States)

    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.

  19. Ozone decomposition

    OpenAIRE

    Batakliev, Todor; Georgiev , Vladimir; Anachkov, Metody; Rakovsky, Slavcho; Zaikov, Gennadi E.

    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...

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

    DEFF Research Database (Denmark)

    Chen, Xiaoying; Song, Fengbin

    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 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kannan Selvaraj, Sathees [Department of Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607 (United States); Feinerman, Alan [Department of Electrical and Computer Engineering, University of Illinois at Chicago, Chicago, Illinois 60607 (United States); Takoudis, Christos G., E-mail: takoudis@uic.edu [Departments of Bioengineering and Chemical Engineering, University of Illinois at Chicago, Chicago, Illinois 60607 (United States)

    2014-01-15

    In this work, a novel liquid tin(II) precursor, tin(II)acetylacetonate [Sn(acac){sub 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 SnO{sub x}–Si interface. The resistivity of the SnO{sub x} films was calculated to be 0.3?? cm. Results of this work demonstrate the possibility of introducing Sn(acac){sub 2} as tin precursor to deposit conducting ALD SnO{sub x} thin films on a silicon surface, with clean interface and no formation of undesired SiO{sub 2} or other interfacial reaction products, for transparent conducting oxide applications.

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

    International Nuclear Information System (INIS)

    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?? 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

  3. Hafnium silicate formation by ultra-violet/ozone oxidation of hafnium silicide

    International Nuclear Information System (INIS)

    We report the room temperature growth of hafnium silicate by ultra-violet/ozone oxidation of hafnium silicide. Hafnium silicide was deposited by magnetron sputtering on hydrogen terminated (1 0 0) Si. The film was then exposed to UV radiation while in an O2 ambient. Hafnium silicate films are obtained with no detectable SiOx interfacial layer as characterized by X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy

  4. Spring leaf flush in aspen (Populus tremuloides) clones is altered by growth at elevated carbon dioxide and elevated ozone

    Science.gov (United States)

    Early spring leaf out is important to the success of trees competing for light and space in dense forest plantation canopies. In this study, we investigated spring leaf flush and how elevated carbon dioxide concentration and elevated ozone concentration altered leaf area index development in a clos...

  5. Slow fatigue crack growth in aluminium and magnesium cast alloys in ambient air and in a vacuum; Langsames Ermuedungsrisswachstum in Aluminium- und Magnesiumgusslegierungen in Raumluft und in Vakuum

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, U.; Mayer, H.; Tschegg, S.; Zettl, B. [Vienna Univ. (Austria). Inst. fuer Meteorologie und Geophysik; Lipowsky, Hj.; Stich, A. [Audi AG, Ingolstadt (Germany); Papakyriacou, M. [ARC Leichtmetallkompetenzzentrum Ranshofen GmbH, Ranshofen (Austria)

    2002-01-01

    The influence of ambient air on near threshold fatigue crack growth in the magnesium cast alloys AZ91 hp, AM60 hp and AS21 hp and in the aluminium cast alloy AlSi9Cu3 has been investigated. Fatigue crack growth properties at a cycling frequency of 20 kHz in ambient air and in a vacuum are significantly different. In a vacuum, the threshold stress intensity amplitude of the aluminium alloy is 30% higher than in ambient air, and the threshold values of the magnesium alloys in a vacuum are up to 85% higher than in ambient air. Moisture of ambient air is responsible for accelerated crack growth at growth rates below 1 - 3 x 10{sup -9} m/cycle (AlSi9Cu3) and 2 - 5 x 10{sup -8} m/cycle (magnesium alloys), respectively. In ambient air a minimum crack growth rate of 5 x 10{sup -11} - 2 x 10{sup -10} m/cycle was observed, whereas far lower minimum growth rates were found in a vacuum. (orig.) [German] Die Arbeit beschaeftigt sich mit dem Einfluss des Umgebungsmediums Raumluft auf das sehr langsame Ermuedungsrisswachstum in den druckgegossenen Magnesiumlegierungen AZ91 hp, AM60 hp und AS21 hp und in der druckgegossenen Aluminiumlegierung AlSi9Cu3. Die bei einer Beanspruchungsfrequenz von 20 kHz gemessenen Rissausbreitungskurven in Raumluft und Vakuum unterscheiden sich im Schwellwertbereich deutlich. Der Schwellwert der Aluminiumlegierung liegt in Vakuum 30% hoeher als in Raumluft, und die Schwellwerte der Magnesiumlegierungen liegen bis zu 85% hoeher. Die in der Raumluft enthaltene Luftfeuchtigkeit ist massgeblich fuer die Beschleunigung des Risswachstums, wobei ein Einfluss bei AlSi9Cu3 bis zu Risswachstumsgeschwindigkeiten von 1 - 3 x 10{sup -9} m/Lastspiel und bei den Magnesiumlegierungen bis zu 2 - 5 x 10{sup -8} m/Lastspiel gefunden wird. In Raumluft wachsen Ermuedungsrisse mit einer Wachstumsgeschwindigkeit von mindestens 5 x 10{sup -11} - 2 x 10{sup -10} m/Lastspiel, waehrend in Vakuum auch wesentlich niedrigere Wachstumsraten gefunden wurden. (orig.)

  6. Plant Species Sensitivity Distributions for ozone exposure

    International Nuclear Information System (INIS)

    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

  7. Adjustments of net photosynthesis in Solanum tuberosum in response to reciprocal changes in ambient and elevated growth CO{sub 2} partial pressures

    Energy Technology Data Exchange (ETDEWEB)

    Sicher, R.C.; Bunce, J.A. [USDA Agricultural Res. Service, Climate Stress Lab., Beltsville, MD (United States)

    2001-07-01

    Single leaf photosynthetic rates and various leaf components of potato (Solanum tuberosum L.) were studied 1-3 days after reciprocally transferring plants between the ambient and elevated growth CO{sub 2} treatments. Plants were raised from individual tuber sections in controlled environment chambers at either ambient (36 Pa) or elevated (72 Pa) CO{sub 2}. One half of the plants in each growth CO{sub 2} treatment were transferred to the opposite CO{sub 2} treatment 34 days after sowing (DAS). Net photosynthesis (P{sub n}) rates and various leaf components were then measured 34, 35 and 37 DAS at both 36 and 72 Pa CO{sub 2}. Three-day means of single leaf P{sub n} rates, leaf starch, glucose, initial and total Rubisco activity, Rubisco protein, chlorophyll (a+b), chlorophyll (a/b), {alpha}-amino N, and nitrate levers differed significantly in the continuous ambient and elevated CO{sub 2} treatments. Acclimation of single leaf P{sub n} rates was partially to completely reversed 3 days after elevated CO{sub 2}-grown plants were shifted to ambient CO{sub 2} whereas there was little evidence of photosynthetic acclimation 3 days after ambient CO{sub 2}-grown plants were shifted to elevated CO{sub 2}. In a four-way comparison of the 36, 72, 36 to 72 (shifted up) and 72 to 36 (shifted down) Pa CO{sub 2} treatments 37 DAS, leaf starch soluble carbohydrates, Rubisco protein and nitrate were the only photosynthetic factors that differed significantly. Simple and multiple regression analyses suggested that negative changes of P{sub n} in response to growth CO{sub 2} treatment were most closely correlated with increased leaf starch levels. (au)

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

    Energy Technology Data Exchange (ETDEWEB)

    Paoletti, Elena [IPP-CNR, Via Madonna del Piano 10, Sesto Fiorentino, I-50019 Florence (Italy)], E-mail: e.paoletti@ipp.cnr.it; Contran, Nicla [Department of Environmental Sciences, 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); Castagna, Antonella; Ranieri, Annamaria [Department of Agricultural Chemistry and Biotechnology, University of Pisa, Via del Borghetto 80, Pisa (Italy); Tagliaferro, Francesco [IPLA, Corso Casale 476, I-10128 Turin (Italy)

    2008-10-15

    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 O{sub 3} effects on leaf growth and visible injury is controversial. - Both biochemical and biophysical processes may regulate EDU action.

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

    Science.gov (United States)

    Paoletti, Elena; Contran, Nicla; Manning, William J; Castagna, Antonella; Ranieri, Annamaria; Tagliaferro, Francesco

    2008-10-01

    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 O(3) effects on leaf growth and visible injury is controversial. PMID:18331769

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

    International Nuclear Information System (INIS)

    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

  11. Growth response of four species of Eastern hardwood tree seedlings exposed to ozone, acidic precipitation, and sulfur dioxide. [Prunus serotina, Acer rubrum, Quercus rubra, Liriodendron tulipifera

    Energy Technology Data Exchange (ETDEWEB)

    Davis, D.D. Skelly, J.M. (Pennsylvania State Univ., University Park (United States))

    1992-03-01

    In 1987 a study was conducted in controlled environment chambers to determine the foliar sensitivity of tree seedlings of eight species to ozone and acidic precipitation, and to determine the influence of leaf position on symptom severity. Jensen and Dochinger conducted concurrent similar studies in Continuously Stirred Tank Reactor (CSTR) chambers with ten species of forest trees. Based on the results of these initial studies, four species representing a range in foliar sensitivity to ozone were chosen: black cherry (Prunus serotina Ehrh.), red maple (Acer rubrum L.), northern red oak (Quercus rubra L.) and yellow-poplar (Liriodendron tulipifera L.). These species were also chosen because of their ecological and/or commercial importance in Pennsylvania. Seedlings were exposed in growth chambers simulated acid rain. In addition acute exposures to sulfur dioxide were conducted in a regime based on unpublished monitoring data collected near coal-fired power plants. The objective of this study was to determine if the pollutant treatments influenced the growth and productivity of seedlings of these four species. This information will help researchers and foresters understand the role of air pollution in productivity of eastern forests.

  12. Ozone measurement systems: associated instrumentation and calibration

    Directory of Open Access Journals (Sweden)

    J. Bellido

    2006-01-01

    Full Text Available The harmful effects produced by ozone have lead to a vast regulation to define and establish the quality goals of ambient air, based on common methods and criteria. The surveillance nets of atmospheric pollution are worldwide extended systems and the applied technology for the ozone measurement is nowadays quite standardized. The aim of this paper is to give a general view of the most common systems used in the ozone measurement in ambient air from a practical point of view. The used instrumentation and the usual calibration methods will be described.

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

    OpenAIRE

    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...

  14. Ozone threat

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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...

  16. Impact of enhanced ozone deposition and halogen chemistry on tropospheric ozone over the Northern Hemisphere

    Science.gov (United States)

    Fate of ozone in marine environments has been receiving increased attention due to the tightening of ambient air quality standards. The role of deposition and halogen chemistry is examined through incorporation of an enhanced ozone deposition algorithm and inclusion of halogen ch...

  17. Inflammatory and Repair Pathways Induced in Human Bronchoalveolar Lavage Cells with Ozone Inhalation

    Science.gov (United States)

    Wong, Hofer; Tenney, Rachel; Chen, Chun; Stiner, Rachel; Balmes, John R.; Paquet, Agnès C.; Arjomandi, Mehrdad

    2015-01-01

    Background Inhalation of ambient levels of ozone causes airway inflammation and epithelial injury. Methods To examine the responses of airway cells to ozone-induced oxidative injury, 19 subjects (7 with asthma) were exposed to clean air (0ppb), medium (100ppb), and high (200ppb) ambient levels of ozone for 4h on three separate occasions in a climate-controlled chamber followed by bronchoscopy with bronchoalveolar lavage (BAL) 24h later. BAL cell mRNA expression was examined using Affymetrix GeneChip Microarray. The role of a differentially expressed gene (DEG) in epithelial injury was evaluated in an in vitro model of injury [16HBE14o- cell line scratch assay]. Results Ozone exposure caused a dose-dependent up-regulation of several biologic pathways involved in inflammation and repair including chemokine and cytokine secretion, activity, and receptor binding; metalloproteinase and endopeptidase activity; adhesion, locomotion, and migration; and cell growth and tumorigenesis regulation. Asthmatic subjects had 1.7- to 3.8-fold higher expression of many DEGs suggestive of increased proinflammatory and matrix degradation and remodeling signals. The most highly up-regulated gene was osteopontin, the protein level of which in BAL fluid increased in a dose-dependent manner after ozone exposure. Asthmatic subjects had a disproportionate increase in non-polymerized osteopontin with increasing exposure to ozone. Treatment with polymeric, but not monomeric, osteopontin enhanced the migration of epithelial cells and wound closure in an ?9?1 integrin-dependent manner. Conclusions Expression profiling of BAL cells after ozone exposure reveals potential regulatory genes and pathways activated by oxidative stress. One DEG, osteopontin, promotes epithelial wound healing in an in vitro model of injury. PMID:26035830

  18. Ozone depletion

    OpenAIRE

    Yanitska, I.V.

    2014-01-01

    The ozone layer is a belt of naturally occurring ozone gas that sits 9.3 to 18.6 miles (15 to 30 kilometers) above Earth and serves as a shield from the harmful ultraviolet B radiation emitted by the sun. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/34904

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

    OpenAIRE

    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-1?, not eosinophils, mediates ozone-induced airway hyperreactivity, but the mechanism at this time point is largely unknown. IL-1? increases ...

  20. Changes in southern Piedmont grassland community structure and nutritive quality with future climate scenarios of elevated tropospheric ozone and altered rainfall patterns.

    Science.gov (United States)

    Gilliland, N J; Chappelka, A H; Muntifering, R B; Ditchkoff, S S

    2016-01-01

    Forage species common to the southern USA Piedmont region, Lolium arundinacea, Paspalum dilatatum, Cynodon dactylon and Trifolium repens, were established in a model pasture system to test the future climate change scenario of increasing ozone exposure in combination with varying rainfall amounts on community structure and nutritive quality. Forages were exposed to two levels of ozone [ambient (non-filtered; NF) and twice ambient (2×) concentrations] with three levels of precipitation (average or ±20% of average) in modified open-top chambers (OTCs) from June to September 2009. Dry matter (DM) yield did not differ over the growing season between forage types, except in primary growth grasses where DM yield was higher in 2× than NF treatment. Primary growth clover decreased in nutritive quality in 2× ozone because of increased concentrations of neutral detergent fibre (NDF), acid detergent fibre (ADF) and acid detergent lignin (ADL). Re-growth clover exhibited the largest decrease in nutritive quality, whereas grasses were not adversely affected in 2× ozone. Re-growth grasses responded positively to 2× ozone exposure, as indicated in increased relative food value (RFV) and percentage crude protein (CP) than NF-exposed re-growth grasses. Effects of precipitation were not significant over the growing season for primary or re-growth forage, except in primary growth grasses where DM yield was higher in chambers with above average (+20%) precipitation. Total canopy cover was significantly higher over the growing season in chambers receiving above average precipitation, but no significant effects were observed with ozone. Results indicate shifts in plant community structure and functioning related to mammalian herbivore herbivory in future climate change scenarios. PMID:25727344

  1. Ozone and cardiovascular injury

    Directory of Open Access Journals (Sweden)

    Rainaldi Giuseppe

    2009-06-01

    Full Text Available Abstract Air pollution is increasingly recognized as an important and modifiable determinant of cardiovascular diseases in urban communities. The potential detrimental effects are both acute and chronic having a strong impact on morbidity and mortality. The acute exposure to pollutants has been linked to adverse cardiovascular events such as myocardial infarction, heart failure and life-threatening arrhythmias. The long-terms effects are related to the lifetime risk of death from cardiac causes. The WHO estimates that air pollution is responsible for 3 million premature deaths each year. The evidence supporting these data is very strong nonetheless, epidemiologic and observational data have the main limitation of imprecise measurements. Moreover, the lack of clinical experimental models makes it difficult to demonstrate the individual risk. The other limitation is related to the lack of a clear mechanism explaining the effects of pollution on cardiovascular mortality. In the present review we will explore the epidemiological, clinical and experimental evidence of the effects of ozone on cardiovascular diseases. The pathophysiologic consequences of air pollutant exposures have been extensively investigated in pulmonary systems, and it is clear that some of the major components of air pollution (e.g. ozone and particulate matter can initiate and exacerbate lung disease in humans 1. It is possible that pulmonary oxidant stress mediated by particulate matter and/or ozone (O3 exposure can result in downstream perturbations in the cardiovasculature, as the pulmonary and cardiovascular systems are intricately associated, and it is well documented that specific environmental toxins (such as tobacco smoke 2 introduced through the lungs can initiate and/or accelerate cardiovascular disease development. Indeed, several epidemiologic studies have proved that there is an association between PM and O3 and the increased incidence of cardiovascular morbidity 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.

  2. Impacts of ozone on trees and crops

    International Nuclear Information System (INIS)

    In this review article, we explore how surface-level ozone affects trees and crops with special emphasis on consequences for productivity and carbon sequestration. Vegetation exposure to ozone reduces photosynthesis, growth, and other plant functions. Ozone formation in the atmosphere is a product of NOx, which are also a source of nitrogen deposition. Reduced carbon sequestration of temperate forests resulting from ozone is likely offset by increased carbon sequestration from nitrogen fertilization. However, since fertilized crop-lands are generally not nitrogen-limited, capping ozone-polluting substances in the USA, Europe, and China can reduce future crop yield loss substantially. (authors)

  3. Inhibitory effects of ambient levels of solar UV-A and UV-B radiation in growth of cv. New Red Fire lettuce

    International Nuclear Information System (INIS)

    The influence of solar UV-A and UV-B radiation at Beltsville, MD, USA, on growth of Lactuca sativa L. (cv. New Red Fire lettuce) was examined during early summer of 1996 and 1997. Plants were grown from seed in plastic window boxes covered with Llumar to exclude UV-A and UV-B, polyester to exclude UV-B, or tefzel (1996) or teflon (1997) to transmit UV-A and UV-B radiation. After 31-34 days, plants grown in the absence of solar UV-B radiation (polyester) had 63 and 57% greater fresh weight and dry weight of tops, respectively, and 57, 72 and 47% greater dry weight of leaves, stems and roots, respectively, as compared to those grown under ambient UV-B (tefzel or teflon). Plants protected from UV-A radiation as well (Llumar) showed an additional 43 and 35% increase, respectively, in fresh and dry weight of tops and a 33 and 33% increase, respectively, in dry weight of leaves and stems, but no difference in root biomass over those grown under polyester. Excluding ambient UV-B (polyester) significantly reduced the UV absorbance of leaf extracts at 270, 300 and 330 nm (presumptive flavonoids) and the concentration of anthocyantins at 550 nm as compared to those of leaf extract from plants grown under ambient UV-A and UV-B. Additional removal of ambient UV-A (Llumar) reduced the concentration of anthocyanins, but had no further effect on UV absorbance at 270, 300 or 330 nm. These findings provide evidence that UV-B radiation is more important than UV-A radiation for flavonoid induction in this red-pigmented lettuce cultivar. Although previous workers have obtained decreases in lettuce yield under enhanced UV-B, this is the first evidence for inhibitory effects of solar UV-A and UV-B radiation on lettuce growth. (au)

  4. Chemical Characterization of Ambient Coarse Particulate Matter in Rural Areas of Arizona Impacted by Significant Population Growth

    Science.gov (United States)

    Characterization of PMc is critical to the understanding of recently observed adverse health effects (e.g., asthma, reduced cardiac variability, etc) from coarse particles in ambient air. PMc mass an (PMc, particles between PM2.5 and PM10) in a rural area of increasing populati...

  5. Ozone modeling

    International Nuclear Information System (INIS)

    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

  6. Ozone decomposition

    Science.gov (United States)

    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

  7. Crescimento de Aegla manuinflata (Decapoda, Anomura, Aeglidae) em ambiente natural Growth of Aegla manuinflata (Decapoda, Anomura, Aeglidae) in natural environment

    OpenAIRE

    André Trevisan; Sandro Santos

    2011-01-01

    O presente trabalho teve como objetivo avaliar o crescimento de Aegla manuinflata Bond-Buckup & Santos, 2009 em ambiente natural. Para isso foram realizadas coletas mensais de abril de 2006 a maio de 2007 no arroio Passo Taquara, no município de São Pedro do Sul, Rio Grande do Sul, Brasil. Os organismos foram coletados utilizando armadilhas plásticas e puçá. Os espécimes foram sexados e tiveram mensurado o comprimento do cefalotórax (CC), em seguida foram devolvidos ao córrego. O crescimento ...

  8. Impact of ozone on understory plants of the aspen zone

    Energy Technology Data Exchange (ETDEWEB)

    Harward, M.R.; Treshow, M.

    1971-01-01

    The purpose of this study was to learn how ozone might affect the growth and reproduction of understory species of the aspen community, and thereby influence its stability and composition. Plants of 15 representative species of the aspen community were grown in chambers and fumigated 4 hours each day, 5 days per week throughout their growing seasons. These included: Achillea millifolium, Chenopodium album, Chenopodium fremontii, Cruciferae sp., Descurainia pinnata, Descurainia sp., Geranium fremontii, Isatis tinctoria, Ligusticum porteri, Lepidium virginicum, Madia glomerata, Polygonum aviculare, Polygonum douglasii, Phacelia heterophylla, Viola italica. Plants were exposed to 30 pphm, 15 pphm, ambient air reaching 5-7 pphm for 2 hours per day, and filtered air. The study was repeated for 3 seasons. Ambient air caused a significant reduction of total plant weight only of Lepidium virginicum. Six species produced fruit and seeds. At 15 pphm, seed production by Madia glomerata and Polygonum douglasii was significantly reduced. At 30 pphm, seed production was also reduced in Polygonum aviculare and Lepidium virginicum. The two most significant conclusions to emerge from the study were first that several species were more sensitive to ozone than might have been suspected. Second, this sensitivity varied sufficiently that major shifts in community composition would be probable following only a year or two of exposure. More tolerant species have no doubt already become dominant over more sensitive species in natural plant communities exposed to elevated ozone concentrations. It must be stressed that the species studied did not necessarily represent the most ozone sensitive members of the community, or the most tolerant.

  9. Interactive effects of ozone and elevated carbon dioxide on the growth and physiology of black cherry, green ash, and yellow-poplar seedlings.

    Science.gov (United States)

    Loats, K V; Rebbeck, J

    1999-08-01

    Potted seedlings of black cherry (Prunus serotina Ehrh.) (BC), green ash (Fraxinus pennsylvanica Marsh.) (GA), and yellow-poplar (Liriodendron tulipifera L.) (YP) were exposed to one of the four treatments: (1) charcoal-filtered air (CF) at ambient CO(2) (control); (2) twice ambient O(3) (2 x O(3)); (3) twice ambient CO(2) (650 microl l(-1)) plus CF air (2 x CO(2)); or (4) twice ambient CO(2) (650 microl l(-1)) plus twice ambient O(3) (2 x CO(2) + 2 x O(3)). The treatments were duplicated in eight continuously stirred tank reactors for 10 weeks. Gas exchange was measured during the last 3 weeks of treatment and all seedlings were destructively harvested after 10 weeks. Significant interactive effects of O(3) and CO(2) on the gas exchange of all three species were limited. The effects of elevated CO(2) and O(3), singly and combined, on light-saturated net photosynthesis (A(max)) and stomatal conductance (g(s)) were inconsistent across species. In all three species, elevated O(3) had no effect on g(s). Elevated CO(2) significantly increased A(max) in GA and YP foliage, and decreased g(s) in YP foliage. Maximum carbon exchange rates and quantum efficiencies derived from light-response curves increased, while compensation irradiance and dark respiration decreased in all three species when exposed to 2 x CO(2). Elevated O(3) affected few of these parameters but any change that was observed was opposite to that from exposure to 2 x CO(2)-air. Interactive effects of CO(2) and O(3) on light-response parameters were limited. Carboxylation efficiencies, derived from CO(2)-response curves (A/C(i) curves) decreased only in YP foliage exposed to 2 x CO(2)-air. In general, growth was significantly stimulated by 2 x CO(2) in all three species; though there were few significant growth responses following exposure to 2 x O(3) or the combination of 2 x CO(2) plus 2 x O(3). Results indicate that responses to interacting stressors such as O(3) and CO(2) are species specific. PMID:15093051

  10. Ozone production and emission precursors during SHARP 2009

    Science.gov (United States)

    Cazorla, M.; Brune, W. H.; Ren, X.; Jobson, B. T.; Lefer, B. L.

    2010-12-01

    Rates of ozone production were measured directly during the Study of Houston Atmospheric Radical Precursors (SHARP) with a new Penn State instrument. The set of data contains low ozone production days and high ozone production days that developed under different meteorological conditions. Among the data collected, there are three verified episodes of high ozone in Houston. The large amount of VOCs combined with NOx emissions from point and mobile sources intensify the production of ozone in this urban center. Interesting correlations between measured ozone production and ambient nitrogen oxides have been found and will be presented. In addition, relationships between known organic radical precursors and measured ozone production will be analyzed. This discussion will be performed within the context of the specific meteorological conditions that favored the accumulation of ozone in Houston in the month of May, 2009.

  11. Ozone as an ecotoxicological problem

    Energy Technology Data Exchange (ETDEWEB)

    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.

  12. Characterization of ozone episodes in urban air

    International Nuclear Information System (INIS)

    The study was directed toward analysis and quantitation of some of the factors that precede the development of ozone episodes in an urban setting. Measurements of pollution and meteorological data were collected in Chicago during August and early September for 54 consecutive days in 1976 and 39 consecutive days in 1977. During these periods, regular measurements were made of the ozone-forming potential of ambient air. Rise in ozone levels was related to passage of a weather front. A method was developed and tested for measuring the ozone-forming potential of ambient air. A rough association was observed between this measurement and O3(max) 3 and 4 days later for the same frontal system

  13. Enhancement of allergic lung sensitization in mice by ozone inhalation

    Energy Technology Data Exchange (ETDEWEB)

    Osebold, J.W.; Zee, Y.C.; Gershwin, L.J.

    1988-07-01

    Inhaled ozone was found to exert an enhancing effect for allergic lung sensitization when mice contracted an aerosolized allergen. The animals were exposed to ozone concentrations of 0.24, 0.16, 0.13, and 0.10 ppm. After 4 days of continuous ozone exposure, the mice had allergen contact from an aerosolized solution of ovalbumin. The animals were then maintained in ambient air for several days before the cycle of ozone and aerosolized allergen was repeated over four allergen contact cycles. Mice were rested in ambient air for a week after the last allergen contact, and they were then tested for allergic sensitization by the intravenous injection of 2 mg of ovalbumin to induce anaphylactic shock in allergic individuals. The control groups of mice were maintained in ambient air throughout the experiment, but they experienced identical allergen contact with the ozone-exposed mice. The phenomenon of allergic enhancement from ozone inhalation was detected at 0.24, 0.16, and 0.13 ppm of ozone. The enhancing effect disappeared at 0.10 ppm of ozone. The study indicated a potential for increasing the number of allergically sensitized individuals when various allergens are inhaled during periods of high ozone exposure with the consequent adverse changes on respiratory membranes. The significance to human health of the allergic enhancement phenomenon by ozone needs investigation.

  14. Fast response cavity enhanced ozone monitor

    OpenAIRE

    Gomez, A. L.; Rosen, E. P.

    2012-01-01

    Ozone is an important atmospheric gas due to its role in air quality and radiative forcing. A new method for sensitive, rapid monitoring of ambient ozone has been developed using a compact platform and relatively inexpensive components. Based on Incoherent Broadband Cavity Enhanced Absorption Spectroscopy (IBB-CEAS), the device utilizes an optical cavity of just 14.5 cm and moderately high reflectivity mirrors (R = 99.3%). Performance of the instrument has been vali...

  15. Ambient Space and Ambient Sensation

    DEFF Research Database (Denmark)

    Schmidt, Ulrik

    2012-01-01

    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 discus...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. Desarrollo de Pinus pseudostrobus bajo distintos ambientes de crecimiento en jardín común / Development of Pinus pseudostrobus under different environments of growth in common garden

    Scientific Electronic Library Online (English)

    Víctor Hugo, Cambrón-Sandoval; Humberto, Suzán-Azpiri; Cuauhtémoc, Sáenz-Romero; Naúm M., Sánchez-Vargas.

    Full Text Available A partir de un análisis de componentes principales (ACP), se plantea la interpretación y clasificación de tres ambientes de competencia sobre el desarrollo de individuos de P. pseudostrobus integrando resultados previamente publicados dentro del mismo ensayo; las variables evaluadas fueron: el creci [...] miento (altura y diámetro a la base del tallo), producción de clorofila (cantidad de pigmentos de clorofila a y b), supervivencia, producción y distribución de biomasa total, raíz, rama, hoja y tallo, y arquitectura de crecimiento (largo de rama y altura de inserción de la primera rama) en familias de medios hermanos de P. pseudostrobus evaluados en un ensayo de jardín común a 10 meses de edad bajo tres ambientes de competencia. (I) baja densidad inter-familiar (0.24 × 0.12 m), (II) alta densidad inter-familiar (0.12 × 0.06 m) y (III) alta densidad intra-familiar (0.12 × 0.06 m). Se estimó que los tres componentes con mayor peso (CP) explican el 82.9% de la variación total. El componente principal de mayor varianza se interpreta como crecimiento (CP1), agrupando a las familias por ambiente de competencia; al aumentar la densidad de plantación, posteriormente, las familias se agrupan por la capacidad de supervivencia y por la plasticidad fisiológica (CP2). Finalmente, la diferencia entre los ambientes la hace la plasticidad fenotípica de las familias como respuesta al ambiente de competencia (cambios en la arquitectura) (CP3). Los resultados evidenciaron un elevado nivel de plasticidad fenotípica de P. pseudostrobus y se hace hincapié en la importancia de la selección de ambientes y de genotipos acordes para aumentar la adaptación y productividad en los programas de mejora. Abstract in english From a principal component analysis (PCA), is is proposed the interpretation and classification of three main environments competition on the development of individuals of P. pseudostrobus integrating previous results within the same trial. The variables were: growth (height and base diameter), chlo [...] rophyll production (chlorophyll pigments total, a, b and the ratio a/b), survival, production and distribution of dry weight biomass (total biomass of root, branch, leaf and stem) and growth architecture (length of branch insertion height and the lowest branch on the stem). All variables were measured in half-sibling families of P. pseudostrobus in a common garden test for 10 months-old seedlings in three competitive environments: (I) inter-family of low density (0.24 × 0.12 m), (II) inter-family of high density (0.12 × 0.06 m) and (III) intra-family with high density (0.12 × 0.06 m). The first three components (PC) explained 82.9% of the total variation. The growth was the major component (PC1), grouping families for competitive environments as PC2 with families grouped by survivability and physiological plasticity, and finally, architectural structural changes as PC3. The results showed a high level of phenotypic plasticity of P. pseudostrobus, and emphasize the importance of the selection of environments and genotypes consistent to enhance adaptation and productivity improvement programs.

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

    DEFF Research Database (Denmark)

    Klumpp, A.; Ansel, W.; Klumpp, G.; Vergne, P.; Sifakis, N.; Sanz, M.J.; Rasmussen, S.; Ro-Poulsen, Helge; Ribas, A.; Penuelas, J.; Kambezidis, H.; He, S.; Garrec, J.P.; Calatayud, V.

    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. Ambient Space and Ambient Sensation

    DEFF Research Database (Denmark)

    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, dehierarchization, ubiquity and the production of unfocused sensations in contrast to the conventional notion of the aesthetic experience as a focused contemplation of a stationary object.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

  2. Ozone matters

    International Nuclear Information System (INIS)

    Starting out with a critical look at the political aspects of sustainability programmes in the United Kingdom - with a particular emphasis on the 'spin' put on the topic by politicians - this editorial article discusses the problem of summer ozone pollution in urban and countryside areas. The measures - such as catalytic converters on cars - already being taken in part to reduce the emission of pollutants from which the ozone is formed are reviewed. The influence of climatic effects are also discussed. The author calls for increased efforts in reducing levels of air pollution and discusses those that are considered the most important

  3. SEASON-LONG ELEVATION OF OZONE CONCENTRATION TO PROJECTED 2050 LEVELS UNDER FULLY OPEN-AIR CONDITIONS SUBSTANTIALLY DECREASES THE GROWTH AND PRODUCTION OF SOYBEAN

    Science.gov (United States)

    -Mean surface ozone concentration is predicted to increase 25% by 2050. Previous chamber studies of crops report large yield losses due to elevation of tropospheric ozone, and have been the basis for projecting economic loss. -This is the first study with a food crop (soybean) using Free-Air gas Con...

  4. OZONE EXPOSURE INITIATES A SEQUENTIAL SIGNALING CASCADE IN AIRWAYS INVOLVING INTERLEUKIN-1BETA RELEASE, NERVE GROWTH FACTOR SECRETION, AND SUBSTANCE P UPREGULATION

    Science.gov (United States)

    Barker, Joshua S.; Wu, Zhongxin; Hunter, Dawn D.; Dey, Richard D.

    2015-01-01

    Previous studies demonstrated that interleukin-1? (IL-1?) and nerve growth factor (NGF) increase synthesis of substance P (SP) in airway neurons both after ozone (O3) exposure and by direct application. It was postulated that NGF mediates O3-induced IL-1? effects on SP. The current study specifically focused on the influence of O3 on IL-1?, NGF, and SP levels in mice bronchoalveolar lavage fluid (BALF) and whether these mediators may be linked in an inflammatory-neuronal cascade in vivo. The findings showed that in vivo O3 exposure induced an increase of all three proteins in mouse BALF and that O3-induced elevations in both NGF and SP are mediated by the inflammatory cytokine IL-1?. Further, inhibition of NGF reduced O3 induced increases of SP in both the lung BALF and lung tissue, demonstrating NGF serves as a mediator of IL-1? effects on SP. These data indicate that IL-1? is an early mediator of O3-induced rise in NGF and subsequent SP release in mice in vivo. PMID:25734767

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

    International Nuclear Information System (INIS)

    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.)

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Scientific Electronic Library Online (English)

    F. A, Lage Filho; L. R. F, Carvalho; M. L. A, Lopes.

    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.

  8. Cyclic-load crack growth in ASME SA-105 grade II steel in high-pressure hydrogen at ambient temperature

    Science.gov (United States)

    Walter, R. J.; Chandler, W. T.

    1976-01-01

    ASME SA-105 Grade II steel, which is used in high-pressure hydrogen compressor systems, is similar to steels used or considered for use in high-pressure hydrogen storage vessels and pipelines. This paper summarizes the results of a program conducted to provide cyclic-load crack growth rate (da/dN) data for a fracture mechanics analysis of a 15,000 psi hydrogen compressor facility which contains pulse quieter and after-cooler separator vessels constructed of the ASME SA-105 Grade II steel. Included in the program were tests performed to assist in establishing operating procedures that could minimize the effect of hydrogen on crack growth rates during operation.

  9. Impacts of ambient salinity and copper on brown algae: 1. Interactive effects on photosynthesis, growth, and copper accumulation.

    Science.gov (United States)

    Connan, Solène; Stengel, Dagmar B

    2011-07-01

    The effect of copper enrichment and salinity on growth, photosynthesis and copper accumulation of two temperate brown seaweeds, Ascophyllum nodosum and Fucus vesiculosus, was investigated in laboratory experiments. A significant negative impact of reduced salinity on photosynthetic activity and growth was observed for both species. After 15 days at a salinity of 5, photosynthesis of A. nodosum was entirely inhibited and growth ceased at a salinity of 15. Increased copper concentration negatively affected photosynthetic activity of A. nodosum and F. vesiculosus resulting in chlorosis and reduced seaweed growth; 5 mg L⁻¹ copper caused an inhibition of the photosynthesis and the degradation of seaweed tips. Under reduced salinity, copper toxicity was enhanced and caused an earlier impact on the physiology of seaweed tips. After exposure to copper and different salinities for 15 days, copper contents of seaweeds were closely related to copper concentration in the water; seaweed copper contents reached their maximum after 1 day of exposure; contents only increased again when additional, free copper was added to the water. At high water copper concentrations or low salinity, or a combination of both, copper content of A. nodosum decreased. By contrast, copper content of F. vesiculosus increased, suggesting that different binding sites or uptake mechanisms exist in the two species. The results suggest that when using brown seaweeds in biomonitoring in situ, any change in the environment will directly and significantly affect algal physiology and thus their metal binding capacity; the assessment of the physiological status of the algae in combination with the analysis of thallus metal content will enhance the reliability of the biomonitoring process. PMID:21549661

  10. The Antarctic Ozone Hole

    Science.gov (United States)

    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…

  11. Comparative study of ozonized olive oil and ozonized sunflower oil

    Scientific Electronic Library Online (English)

    Maritza F., Díaz; Rebeca, Hernández; Goitybell, Martínez; Genny, Vidal; Magali, Gómez; Harold, Fernández; Rafael, Garcés.

    2006-04-01

    Full Text Available Neste estudo, óleos de oliva e girassol ozonizados foram comparados química e microbilogicamente. Estes óleos foram introduzidos em um reator com gás ozônio borbulhante, em banho-maria a temperatura ambiente, até solidificação. O teor de peróxido, de iodo e o grau de acidez foram determinados juntam [...] ente com a atividade antimicrobiana. Os efeitos da ozonização na composição dos ácidos graxos desses óleos foram analisados usando-se a técnica de Cromatografia Gás-Líquido. Um aumento nos valores de peroxidação e de acidez foi observado em ambos os óleos, mas foram maiores no óleo de girassol ozonizado. O teor de iodo obtido no azeite de oliva ozonizado foi zero, enquanto no óleo de girassol ozonizado foi de 8,8 g de iodo per 100 g. A atividade antimicrobiana foi similar para os dois óleos ozonizados, com exceção da Concentração Mínima Bactericida de Pseudomona Aruginosa. A composição dos ácidos graxos nos dois óleos ozonizados mostrou um decréscimo gradual de ácidos graxos insaturados (C18:1, C18:2), com o aumento gradual da ozonização. Abstract in english In this study the ozonized olive and sunflower oils are chemical and microbiologically compared. These oils were introduced into a reactor with bubbling ozone gas in a water bath at room temperature until they were solidified. The peroxide, acidity and iodine values along with antimicrobial activity [...] were determined. Ozonization effects on the fatty acid composition of these oils were analyzed using Gas-Liquid Chromatographic Technique. An increase in peroxidation and acidity values was observed in both oils but they were higher in ozonized sunflower oil. Iodine value was zero in ozonized olive oil whereas in ozonized sunflower was 8.8 g Iodine per 100 g. The antimicrobial activity was similar for both ozonized oils except for Minimum Bactericidal Concentrations of Pseudomona aeruginosa. Composition of fatty acids in both ozonized oils showed gradual decrease in unsaturated fatty acids (C18:1, C18:2) with gradual increase in ozone doses.

  12. Ozone inhibits corrosion in cooling towers

    Science.gov (United States)

    French, K. R.; Howe, R. D.; Humphrey, M. F.

    1980-01-01

    Commercially available corona discharge ozone generator, fitted onto industrial cooling tower, significantly reduces formation of scales (calcium carbonate) and corrosion. System also controls growth of algae and other microorganisms. Modification lowers cost and improves life of cooling system.

  13. Growth of Crassostrea gasar cultured in marine and estuary environments in Brazilian waters / Crescimento de Crassostrea gasar cultivada em ambientes marinho e estuarino em águas brasileiras

    Scientific Electronic Library Online (English)

    Gustavo Ruschel, Lopes; Carlos Henrique Araujo de Miranda, Gomes; Cláudio Rudolfo, Tureck; Claudio Manuel Rodrigues de, Melo.

    2013-08-01

    Full Text Available O objetivo deste trabalho foi avaliar o crescimento da ostra-do-mangue Crassostrea gasar cultivada em ambiente marinho e estuarino. As ostras foram cultivadas por 11 meses em sistema de espinhel, em dois locais de estudo - São Francisco do Sul e Florianópolis -, em Santa Catarina. A concentração de [...] clorofila-?, a temperatura e a salinidade da água foram registradas semanalmente. As ostras foram medidas mensalmente (tamanho da concha e ganho de peso) para avaliar o crescimento. No final do período de cultivo, os pesos médios de carne úmida, carne seca e concha foram determinados, bem como a distribuição das ostras por classes de tamanho. Seis modelos não lineares (logístico, exponencial, Gompertz, Brody, Richards e Von Bertalanffy) foram ajustados aos dados de crescimento das ostras. As médias finais de tamanho da concha foram maiores em São Francisco do Sul do que em Florianópolis. Além disso, as ostras cultivadas em São Francisco do Sul apresentaram distribuição mais uniforme nas classes de tamanho do que aquelas cultivadas em Florianópolis. Os maiores valores médios de peso de carne úmida e peso de concha foram observados em São Francisco do Sul, enquanto o peso da carne seca não diferiu entre os locais. O ambiente estuarino é mais promissor para o cultivo de ostras. Abstract in english The objective of this work was to evaluate the growth of the mangrove oyster Crassostrea gasar cultured in marine and estuarine environments. Oysters were cultured for 11 months in a longline system in two study sites - São Francisco do Sul and Florianópolis -, in the state of Santa Catarina, Southe [...] rn Brazil. Water chlorophyll-? concentration, temperature, and salinity were measured weekly. The oysters were measured monthly (shell size and weight gain) to assess growth. At the end of the culture period, the average wet flesh weight, dry flesh weight, and shell weight were determined, as well as the distribution of oysters per size class. Six nonlinear models (logistic, exponential, Gompertz, Brody, Richards, and Von Bertalanffy) were adjusted to the oyster growth data set. Final mean shell sizes were higher in São Francisco do Sul than in Florianópolis. In addition, oysters cultured in São Francisco do Sul were more uniformly distributed in the four size classes than those cultured in Florianópolis. The highest average values of wet flesh weight and shell weight were observed in São Francisco do Sul, whereas dry flesh weight did not differ between the sites. The estuary environment is more promising for the cultivation of oysters.

  14. Stratospheric ozone

    OpenAIRE

    M Gil

    2006-01-01

    Stratospheric ozone acquired a huge importance two decades ago because of the discovery of strong anomalies above the Antarctica due to gases of anthropogenic origin. From that date, stratosphere has become one of the research lines receiving more funding. A result, an important progress in the development of observational techniques, the understanding of the dynamics of the polar regions and, above all, in understanding of the chemical interactions among the species that influence the chemic...

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Paoletti, Elena [Institut Plant Protection (IPP), National Council Research (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino, Florence (Italy)], E-mail: e.paoletti@ipp.cnr.it; Ferrara, Anna Maria [Istituto per le Piante da Legno e l' Ambiente (IPLA), Corso Casale 476, 10132 Turin (Italy); Calatayud, Vicent; Cervero, Julia [Fundacion C.E.A.M., Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Giannetti, Fabio [Istituto per le Piante da Legno e l' Ambiente (IPLA), Corso Casale 476, 10132 Turin (Italy); Sanz, Maria Jose [Fundacion C.E.A.M., Charles R. Darwin 14, Parc Tecnologic, 46980 Paterna, Valencia (Spain); Manning, William J. [Department of Plant, Soil and Insect Sciences, University of Massachusetts, Amherst, MA 01003-9320 (United States)

    2009-03-15

    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.

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

    International Nuclear Information System (INIS)

    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

  18. Ozone tolerance of European larch (Larix decidua Mill.)

    International Nuclear Information System (INIS)

    Larix decidua has been classified as a tree species ''highly sensitive'' to ozone. However, in Austria its main distribution is at altitudes where the recommended limits for ozone concentrations for sensitive plants are strongly exceeded for long periods. Long-term fumigation of twigs of a mature larch tree with ambient or double ambient air ozone concentrations did not cause any visible damage or negative influence on the gas exchange. However very high exposure of 1200 ppb ozone led to acute damage in long shoot needles with high gas exchange rates in the sun, but led only to small damages on shaded long shoots. Needles on short shoots neither developed visible damages nor were their capabilities for photosynthesis and stomatal regulation reduced, nor did they exhibit signs of premature senescence. According to the results of this investigation, European larch should be classified as ''intermediate'' or even as ''less sensitive'' to ozone. (orig.)

  19. Global impact of the Antarctic ozone hole - Chemical propagation

    Science.gov (United States)

    Prather, Michael; Jaffe, Andrew H.

    1990-01-01

    A model is presented for the chemical mixing of stratospheric air, that combines photochemistry, molecular diffusion, and strain (i.e., the stretching of air parcels due to wind shear). The model is applied to the case in which chemically perturbed air parcels from the Antarctic stratosphere are transported to mid-latidudes and strained into thin ribbon-like filaments until they are diffusively mixed with the ambient stratosphere. Results show that, following the breakup of the polar vortex, Antarctic air with substantially depleted ozone will not contribute any additional ozone loss at mid-latitudes as it is mixed with ambient air, supporting the results of simulations of the Antarctic ozone hole by Prather et al. (1990). Nevertheless, air processed by polar stratospheric clouds but transported to mid-latitudes before substantive ozone depletion, can lead to additional loss after mixing with ambient air.

  20. Effects of ozone on growth, yield and leaf gas exchange rates of four Bangladeshi cultivars of rice (Oryza sativa L.)

    International Nuclear Information System (INIS)

    To assess the effects of tropospheric O3 on rice cultivated in Bangladesh, four Bangladeshi cultivars (BR11, BR14, BR28 and BR29) of rice (Oryza sativa L.) were exposed daily to charcoal-filtered air or O3 at 60 and 100 nl l-1 (10:00-17:00) from 1 July to 28 November 2008. The whole-plant dry mass and grain yield per plant of the four cultivars were significantly reduced by the exposure to O3. The exposure to O3 significantly reduced net photosynthetic rate of the 12th and flag leaves of the four cultivars. The sensitivity to O3 of growth, yield and leaf gas exchange rates was not significantly different among the four cultivars. The present study suggests that the sensitivity to O3 of yield of the four Bangladeshi rice cultivars is greater than that of American rice cultivars and is similar to that of Japanese rice cultivars and that O3 may detrimentally affect rice production in Bangladesh. - Bangladeshi cultivars of rice are sensitive to O3 below 100 ppb.

  1. 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

    Directory of Open Access Journals (Sweden)

    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.

  2. EFFECT OF OZONE ON DIESEL EXHAUST PARTICLE TOXICITY

    Science.gov (United States)

    Ambient particulate matter (PM) concentrations have been associated with mortality and morbidity. Diesel exhaust particles (DEP) are present in ambient urban air PM. Coexisting with DEP (and PM) is ozone (O(3)), which has the potential to react with some components of DEP. Some r...

  3. Ozone liquefaction technology; Ekika ozon gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-02-29

    Application of ozone to a next-generation semiconductor production field is expected because of its strong oxidizing power and less residual content after reaction. However, since the concentration of ozone obtained by ozonizer is only 1-10%, production of high-concentration and high-purity ozone is indispensable to use it for semiconductor production processes. The production equipment of high-purity liquid ozone was thus fabricated in combination with Electrotechnical Laboratory, Agency of Industrial Science and Technology. This equipment stores pure liquid ozone through separation and liquefaction of ozone under low-temperature environment, and supplies high-purity ozone gas (-100%) precisely and safely by temperature control. This large- capacity equipment is expected for formation of high-Tc superconducting oxide films, silicon oxide films and insulation films for semiconductors, and for ashing of resist. (translated by NEDO)

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

    International Nuclear Information System (INIS)

    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 ?c [O2] = 3.2 x 10-16 cm2 and ?c [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 ?i-Ar = 2.1 x 10-16 cm2 and ion-oxygen ?i-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

  5. Ozone influence on native vegetation in the Jizerske hory Mts. of the Czech Republic: results based on ozone exposure and ozone-induced visible symptoms.

    Science.gov (United States)

    H?nová, Iva; Matoušková, Leona; Srn?nský, Radek; Koželková, Klára

    2011-12-01

    Ozone levels in the Jizerske hory Mts. measured at 13 sites by diffusive samplers during the 2006 and 2007 vegetation seasons are presented. A significant ozone gradient (5.4 ppb in 2006 and 4.0 ppb in 2007) per 100 m difference in altitude between 370 and 1,100 m a.s.l. was recorded. High-resolution maps of phytotoxic potential were developed. The AOT40 threshold (5 ppm h) was exceeded over the entire area with the highest levels exceeding this threshold by 12 times in the upper portions of the mountains. Ozone visible injury was evaluated at four of the monitoring sites on seven native plant and tree species. Four species showed ozone-like symptoms, two of which (Rubus idaeus and Fagus sylvatica) were confirmed as ozone-induced. Our results indicate that ambient ozone is likely to have a much lower impact on the Jizerske hory Mts. vegetation than expected, considering the measured ambient ozone exposures and favourable environmental conditions for ozone uptake. PMID:21374050

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

    Science.gov (United States)

    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. Influence of temperature and humidity on ozone-surface reactivity was not strong.

  7. Growth, nitrogen uptake, and metabolism in two semiarid shrubs grown at ambient and elevated atmospheric CO2 concentrations: effects of nitrogen supply and source.

    Science.gov (United States)

    Causin, Humberto Fabio; Tremmel, David C; Rufty, Thomas W; Reynolds, James F

    2004-04-01

    The effect of differences in nitrogen (N) availability and source on growth and nitrogen metabolism at different atmospheric CO(2) concentrations in Prosopis glandulosa and Prosopis flexuosa (native to semiarid regions of North and South America, respectively) was examined. Total biomass, allocation, N uptake, and metabolites (e.g., free NO(3)(-), soluble proteins, organic acids) were measured in seedlings grown in controlled environment chambers for 48 d at ambient (350 ppm) and elevated (650 ppm) CO(2) and fertilized with high (8.0 mmol/L) or low (0.8 mmol/L) N (N(level)), supplied at either 1 : 1 or 3 : 1 NO(3)(-) : NH(4)(+) ratios (N(source)). Responses to elevated CO(2) depended on both N(level) and N(source), with the largest effects evident at high N(level). A high NO(3)(-) : NH(4)(+) ratio stimulated growth responses to elevated CO(2) in both species when N was limiting and increased the responses of P. flexuosa at high N(level). Significant differences in N uptake and metabolites were found between species. Seedlings of both species are highly responsive to N availability and will benefit from increases in CO(2), provided that a high proportion of NO(3)- to NH(4)-N is present in the soil solution. This enhancement, in combination with responses that increase N acquisition and increases in water use efficiency typically found at elevated CO(2), may indicate that these semiarid species will be better able to cope with both nutrient and water deficits as CO(2) levels rise. PMID:21653412

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

    International Nuclear Information System (INIS)

    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

  9. A versatile low-pressure ozone source

    International Nuclear Information System (INIS)

    A low-pressure source for pure ozone has been developed and successfully tested in the growth of oxide superconductor thin films. Ozone is selectively adsorbed on silica gel at a temperature of -77 degree C from an O3/O2 gas mixture stream containing 8 wt% O3, produced by a commercial ozone generator. Since only O3 is trapped, no further purification steps are required. Ozone/gel loading factors below 10% (wt/wt) ensure the safe storage of O3 over prolonged periods. Pure O3 is extracted from the silica gel trap, in which the O3 vapor pressure is maintained at around 10 mTorr, by applying a dynamic vacuum. Films of Ba2YCu3O7-? with Tc above 86 K have been grown in situ by molecular beam epitaxy techniques using this ozone source

  10. Secondary maxima in ozone profiles

    OpenAIRE

    Lemoine, R

    2004-01-01

    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 secondary maxima is related to...

  11. EFFECT OF AN OZONE INJURY RETARDANT CHEMICAL ON ISOZYME PROFILES FROM ALFALFA CALLUS IN VITRO

    Science.gov (United States)

    Plant ozone injury retardant (EDU or ethylenediurea) at 1.0 ppm inhibited growth of callus of alfalfa cultivars Williamsburg (ozone-sensitive) and MSB-CW5An2(ozone-insensitive) germplasm of Medicago sative. The presence of EDU(0.1 ppm) in growth medium increased the number of pro...

  12. Ozone Hole Over Antarctica

    Science.gov (United States)

    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

  13. Impacts of ozone on trees and crops; Impacts de l'ozone sur les arbres et les recoltes

    Energy Technology Data Exchange (ETDEWEB)

    Felzer, B.S.; Cronina, T.; Melillo, J.M. [The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA (United States); Reilly, J.M.; Xiaodong, Wang [Joint Program on the Science and Policy of Global Change, Massachusetts Institute of Technology, Cambridge, MA (United States)

    2007-10-15

    In this review article, we explore how surface-level ozone affects trees and crops with special emphasis on consequences for productivity and carbon sequestration. Vegetation exposure to ozone reduces photosynthesis, growth, and other plant functions. Ozone formation in the atmosphere is a product of NO{sub x}, which are also a source of nitrogen deposition. Reduced carbon sequestration of temperate forests resulting from ozone is likely offset by increased carbon sequestration from nitrogen fertilization. However, since fertilized crop-lands are generally not nitrogen-limited, capping ozone-polluting substances in the USA, Europe, and China can reduce future crop yield loss substantially. (authors)

  14. Ambient intelligence

    CERN Document Server

    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.

  15. Emergência e crescimento inicial de Tabebuia heptaphylla (Vell.) Toledo em ambientes contrastantes de luz / Emergency and initial growth of Tabebuia heptaphylla (Vell.) Toledo in contrasting light environments

    Scientific Electronic Library Online (English)

    Viviane Peixoto, Borges; Maria Angélica Pereira de Carvalho, Costa; Rogério Ferreira, Ribas.

    2014-06-01

    Full Text Available Tabebuia heptaphylla (Vell.) Toledo, popularmente conhecida como ipê-roxo ou ipê-roxo-desete-folhas, é uma Bignoniaceae nativa da Mata Atlântica, de importância econômica, medicinal e ornamental, além de ser indicada para reflorestamentos. Entretanto, informações ecofisiológicas sobre essa espécie a [...] inda são escassas. Assim, visando dispor de informações que auxiliem na sua propagação e conservação, este trabalho avaliou a emergência e crescimento inicial dessa espécie em regimes contrastantes de luz. Foram realizados dois experimentos independentes. O primeiro em condições controladas, com os tratamentos 70% de sombreamento e a pleno sol; e o segundo em ambiente natural, com os tratamentos clareira e sub-bosque. Entre os parâmetros utilizados para avaliar a emergência sob influência das intensidades luminosas, apenas a porcentagem de emergência diferiu estatisticamente no ambiente natural, sendo superior na clareira. Em condições controladas, houve significância para a velocidade de emergência, sendo maior nas plantas submetidas ao a pleno sol. A espécie apresentou reduzido crescimento inicial no sub-bosque, sendo todos os parâmetros estatisticamente inferiores em relação às plantas da clareira, com exceção da razão de área foliar e área foliar específica. Em condições controladas, os resultados que diferiram significativamente foram todos superiores nas plantas a pleno sol. O estudo evidenciou que a espécie apresenta capacidade de formar plântulas em diferentes regimes de luz, inclusive sob forte sombreamento natural, porém essa condição reduz significativamente seu crescimento inicial, sendo este favorecido por maiores intensidades luminosas. Abstract in english Tabebuia heptaphylla (Vell.) Toledo, known as "ipê-roxo" or" ipê-roxo-de sete-folhas", is a native species of Atlantic Forest, with an economic, medicinal and ornamental role, suitable for reforestation. However, ecophysiological information about it is scarce. In order to provide information about [...] propagation and conservation for this specie, the present study evaluated emergence and early growth of this species in different light exposure. We lead two independent trials. In the first we considered controlled conditions, with two treatments: 70% shade and full sun. The second was developed in a natural environment, with two treatments: gap and understory environments. From the total parameters used to evaluate the emergence of the species under influence of light intensities, only the emergence percentage was statistically different from the natural environment, with high values observed at gap treatment. Significant differences were observed in controlled environment, considering the emergence speed. This variable was higher in plants grown under full sun. Slower initial growth was observed for plants regenerated in the understory, compared to the plants growing in gaps, except for following characteristics: leaf area ration and specific leaf area. In controlled conditions, the results with higher significant differences were observed for plants under full sun. The study shows that the species has the capacity to germinate in different light conditions, even under strong natural shading. However, this condition reduces significantly its initial growth, which is favored by higher light intensities.

  16. Growth analysis of sweet pepper cultivated in coconut fiber in a greenhouse / Análise de crescimento de pimentão cultivado em fibra de coco em ambiente protegido

    Scientific Electronic Library Online (English)

    Hamilton César de O, Charlo; Sueyde F de, Oliveira; Renata, Castoldi; Pablo F, Vargas; Leila T, Braz; José Carlos, Barbosa.

    2011-09-01

    Full Text Available O conhecimento sobre o crescimento das culturas permite o planejamento de métodos de cultivo racional, que contribuirá para alcançar um maior potencial de espécies vegetais, além de fornecer informações para a construção de modelos matemáticos descritivos de crescimento. Diante disto, o objetivo des [...] te estudo foi determinar a curva de crescimento do pimentão amarelo (híbrido Eppo) cultivado em fibra de coco em ambiente protegido com fertirrigação. O experimento compreendeu inicialmente 160 plantas, divididas em quatro blocos, sendo colhidas duas por bloco a cada 21 dias após o transplante, finalizando-se aos 189 dias após o transplante. O cultivo de pimentão foi feito em vasos plásticos de 13 L contendo fibra de coco, distribuídos em fila dupla, com espaçamento de 0,5 x 0,8 m entre fileiras simples e 1,1 m entre fileiras duplas. Em cada colheita foram avaliados o crescimento das plantas e a produção e qualidade de frutos maduros. A massa seca da parte aérea aumentou com o tempo, seguindo um modelo exponencial de primeira ordem, atingindo um máximo de 451,5 g/planta aos 189 dias após o transplante (DAT). A produção de massa seca de folhas, caule, raiz e frutos também aumentou ao longo do tempo, seguindo o mesmo modelo, atingindo valores máximos de 68.7, 65.8, 11.5 e 302.9 g/planta, respectivamente, aos 189 DAT. O mesmo ocorreu com a área foliar por planta, altura da planta e a taxa de crescimento absoluto, cujos valores máximos foram de 6.183,5 cm², 136.9 cm e 4.4 g/planta/dia, respectivamente. O crescimento das plantas foi contínuo ao longo do ciclo, sendo que a maior quantidade de massa seca foi acumulada nos frutos, cuja produção comercial chegou a 97.3 t ha-1, sendo totalmente classificados como Extra. Abstract in english Knowledge about the growth of crops allows the planning of rational cultivation methods which contribute to achieve greater potential of plant species, besides supplying information for the construction of descriptive mathematical models of growth. The growth curve of sweet pepper (Eppo hybrid), cul [...] tivated in coconut fiber in a greenhouse with fertirrigation, was determined. The experiment consisted initially of 160 plants divided into four blocks. Two plants were analyzed per block every 21 days after transplanting, ending at 189 days after transplant. The cultivation was carried out in plastics pots of 13 L containing coconut fiber, which were arranged in double rows, spaced 0.5 x 0.8 m between simple rows and 1.1 m between double rows. In each harvest the plant growth, production and quality of mature fruits were evaluated. The dry mass of the shoot increased with time, following the experimental model exponential of first order, reaching a maximum of 451.5 g/plant, 189 days after transplanting (DAT). The production of dry mass of leaves, stem, root and fruit also increased over time reaching maximum values of 68.7, 65.8, 11.5 and 302.9 g/plant, respectively, at 189 DAT. The same occurred with the leaf area per plant, plant height and the absolute rate of growth, whose maximum values were 6.183,5 cm², 136.9 cm and 4.4 g/plant/day, respectively. The growth of the plant was continuous throughout the cycle, and the highest amount of dry mass was accumulated in fruits, reaching a marketable production of 97.3 t ha-1. All fruits were classified as Extra.

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

    Science.gov (United States)

    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...

  18. Salud y medio ambiente: Health and environment

    Scientific Electronic Library Online (English)

    Jesús, Méndez Martínez; Arelis, Alberto Palenzuela; Ernesto, Morales Santana.

    2009-10-01

    Full Text Available Motivado por la importancia del control del medio ambiente se realiza un panel con los estudiantes de la especialidad de Tecnología de la Salud en el municipio de Matanzas, con el objetivo de fomentar en estos una conciencia ambientalista y de esta forma sensibilizar a los mismos, para ser defensore [...] s en la protección del medio ambiente y así elevar el conocimiento en cuanto a materia ambiental. Desde el triunfo revolucionario en 1959, la protección del medio ambiente y el uso racional de los recursos naturales ha sido objetivo estratégico nacional. Y en medio de la difícil situación económica actual, los esfuerzos por encausar la recuperación económica y la protección ambiental con un enfoque integral, constituyen un importante desafío para los cubanos. La contaminación de ríos y arroyos por contaminantes químicos se ha convertido en uno de los problemas ambientales más graves de nuestra sociedad. El ozono es un contaminante que produce afectaciones a la salud. La explotación forestal debe ser realizada sobre la base de garantizar la repoblación. Son diversos los factores que determinan el crecimiento elevado de la población en los países subdesarrollados. La concentración de la población, la industria y el transporte automotor en zonas urbanas ha producido un desequilibrio ecológico con grave afectación a la higiene del ambiente. Cuba, a pesar de ser un país subdesarrollado, el crecimiento económico y la industrialización han llevado aparejadas medidas consecuentes para la protección del ambiente y el desarrollo sostenible. Los riesgos como consecuencia de los fenómenos naturales o provocados por las actividades humanas están íntimamente relacionados con la naturaleza de los mismos. En todos los casos se hacen necesario priorizar los servicios de saneamiento básico esenciales para garantizar la salud de la población . Abstract in english Due to the importance of the environmental control, we carried out a debate with the students of the specialty of Health Technologies in the municipality of Matanzas with the objective of forming an environmental awareness and inducing them to be defenders of the environmental protection, and also r [...] aising their knowledge on the environmental matters. Since the triumph of the Cuban revolution in 1959, environmental protection and rational use of the natural resources have been a national strategic objective. Inserted in the current difficult economic situation, the efforts for achieving the economic recuperation and environmental protection through an integral approach are an important challenge for Cubans. Rivers and brooks contamination by chemical substances has become one of the most serious environmental problems in our society. Ozone is a contaminant producing health affections. Forestal exploitation should be carried on the bases of warranting repopulation. Several factors determine a high growth of population in the underdeveloped countries. The concentration of population, industries and auto transport in urban areas has produced an ecological disequilibrium with serious damage of the environmental hygiene. Although Cuba is an underdeveloped country, the economic growth and industrialization have been led together with tenacious measures to protect the environment and a sustainable development. Risks due to natural phenomena or caused by human activity are tightly related with their nature. In all the cases it is necessary to pay an especial attention to the services and measures guarantying the population health.

  19. Salud y medio ambiente: Health and environment

    Directory of Open Access Journals (Sweden)

    Jesús Méndez Martínez

    2009-10-01

    Full Text Available Motivado por la importancia del control del medio ambiente se realiza un panel con los estudiantes de la especialidad de Tecnología de la Salud en el municipio de Matanzas, con el objetivo de fomentar en estos una conciencia ambientalista y de esta forma sensibilizar a los mismos, para ser defensores en la protección del medio ambiente y así elevar el conocimiento en cuanto a materia ambiental. Desde el triunfo revolucionario en 1959, la protección del medio ambiente y el uso racional de los recursos naturales ha sido objetivo estratégico nacional. Y en medio de la difícil situación económica actual, los esfuerzos por encausar la recuperación económica y la protección ambiental con un enfoque integral, constituyen un importante desafío para los cubanos. La contaminación de ríos y arroyos por contaminantes químicos se ha convertido en uno de los problemas ambientales más graves de nuestra sociedad. El ozono es un contaminante que produce afectaciones a la salud. La explotación forestal debe ser realizada sobre la base de garantizar la repoblación. Son diversos los factores que determinan el crecimiento elevado de la población en los países subdesarrollados. La concentración de la población, la industria y el transporte automotor en zonas urbanas ha producido un desequilibrio ecológico con grave afectación a la higiene del ambiente. Cuba, a pesar de ser un país subdesarrollado, el crecimiento económico y la industrialización han llevado aparejadas medidas consecuentes para la protección del ambiente y el desarrollo sostenible. Los riesgos como consecuencia de los fenómenos naturales o provocados por las actividades humanas están íntimamente relacionados con la naturaleza de los mismos. En todos los casos se hacen necesario priorizar los servicios de saneamiento básico esenciales para garantizar la salud de la población .Due to the importance of the environmental control, we carried out a debate with the students of the specialty of Health Technologies in the municipality of Matanzas with the objective of forming an environmental awareness and inducing them to be defenders of the environmental protection, and also raising their knowledge on the environmental matters. Since the triumph of the Cuban revolution in 1959, environmental protection and rational use of the natural resources have been a national strategic objective. Inserted in the current difficult economic situation, the efforts for achieving the economic recuperation and environmental protection through an integral approach are an important challenge for Cubans. Rivers and brooks contamination by chemical substances has become one of the most serious environmental problems in our society. Ozone is a contaminant producing health affections. Forestal exploitation should be carried on the bases of warranting repopulation. Several factors determine a high growth of population in the underdeveloped countries. The concentration of population, industries and auto transport in urban areas has produced an ecological disequilibrium with serious damage of the environmental hygiene. Although Cuba is an underdeveloped country, the economic growth and industrialization have been led together with tenacious measures to protect the environment and a sustainable development. Risks due to natural phenomena or caused by human activity are tightly related with their nature. In all the cases it is necessary to pay an especial attention to the services and measures guarantying the population health.

  20. TOWARDS RELIABLE AND COST-EFFECTIVE OZONE EXPOSURE ASSESSMENT: PARAMETER EVALUATION AND MODEL VALIDATION USING THE HARVARD SOUTHERN CALIFORNIA CHRONIC OZONE EXPOSURE STUDY DATA

    Science.gov (United States)

    Accurate assessment of chronic human exposure to atmospheric criteria pollutants, such as ozone, is critical for understanding human health risks associated with living in environments with elevated ambient pollutant concentrations. In this study, we analyzed a data set from a...

  1. Assessment of Protective Effect of Some Modern Agrochemicals against Ozone-Induced Stress in Sensitive Clover and Tobacco Cultivars

    OpenAIRE

    Barbara Godzik; Nataliya Pavluchenko; Nataliya Didyk; Oleg Blum

    2011-01-01

    Some modern agrochemicals with antioxidant potential were tested for their protective effect against ozone injury using clover and tobacco ozone-sensitive cultivars as model plants subjected to ambient ozone at two sites (Kyiv city in Ukraine and Szarów village in Poland). All used agrochemicals showed partial protective effects against ozone injury on clover and tobacco. Conducted studies confirmed the effectiveness of modern fungicides belonging to strobilurin group as protectants of sensit...

  2. The effect of ozone associated with summertime photochemical smog on the frequency of asthma visits to hospital emergency departments

    Energy Technology Data Exchange (ETDEWEB)

    Cody, R.P. (Robert Wood Johnson Medical School, Piscataway, NJ (United States)); Weisel, C.P.; Lioy, P.J. (Robert Wood Johnson Medical School, Piscataway, NJ (United States) Environmental and Occupational Health Sciences Institute, Piscataway, NJ (United States)); Birnbaum, G. (Morristown Memorial Hospital, NJ (United States))

    1992-08-01

    A retrospective study using ambient ozone, temperature, and other environmental variables and their effect on the frequency of hospital visits for asthma was conducted in New Jersey, an area that often exceeds the allowable national standard for ozone. Data on emergency department visits for asthma, bronchitis, and finger wounds (a nonrespiratory control) were analyzed for the period May through August for 1988 and 1989. Asthma visits were correlated with temperature while the correlation between asthma visits and ozone concentration was nonsignificant. However, when temperature was controlled for in a multiple regression analysis, a highly significant relationship between asthma visits and ozone concentration was identified. Between 13 and 15% of the variability of the asthma visits and ozone concentration was identified. Between 13 and 15% of the variability of the asthma visits was explained in the regression model by temperature and ambient ozone levels. This association, when compared to similar studies in Canada, shows the contribution of ozone to asthma admissions to be stronger in areas with higher ozone concentrations. Thus, among regions with periodic accumulations of ozone in the ambient atmosphere, an exposure-response relationship may be discernible. This supports the need to attain air quality standards for ozone to protect individuals in the general population from the adverse health effects caused by ambient ozone exposure. 21 refs., 1 fig., 6 tabs.

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

    International Nuclear Information System (INIS)

    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 global radiation. In the model with all factors, Species was most important, and when Species was omitted, stomatal conductance was the most important determinant for leaf injury to occur, whereas mean relative growth rate was less important. With no plant-related factors included, air vapour pressure deficit and AOT40 were of highest importance. Only in eight species was a positive relationship found between these two factors during the five days before the onset of injury, indicating increasing protection from ozone with increasing air vapour pressure deficit in some but not all species. These data show that across a range of grassland species, leaf injury caused by elevated levels of ozone is most likely to occur in species with high stomatal conductance and that protection from ozone during dry periods is species-specific and depends on a reduction in stomatal conductance due to a decrease in soil moisture potential. Protection under increased vapour pressure deficit can occur in some but not all species, depending on the relationship between stomatal conductance and air vapour pressure deficit. (author)

  4. Ozone mass transfer and kinetics experiments

    International Nuclear Information System (INIS)

    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

  5. Antarctic Ozone Hole, 2000

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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)

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

    Directory of Open Access Journals (Sweden)

    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.

  8. Stratospheric ozone depletion

    International Nuclear Information System (INIS)

    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)

  9. The Antarctic ozone hole

    International Nuclear Information System (INIS)

    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

  10. Antarctic ozone depletion

    International Nuclear Information System (INIS)

    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

  11. Ozone as air pollutant; Ozon als Luftschadstoff

    Energy Technology Data Exchange (ETDEWEB)

    Englert, N. [Umweltbundesamt, Berlin (Germany)

    2000-07-01

    Ozone is a natural component in the air. However, its concentration is increased due to anthropogenic activities. Being a strong oxidant of low water solubility, ozone can penetrate deeply into the respiratory tract where it acts as an irritant. Increased concentrations of ozone result in impaired lung function values, in an increase in asthma attacks, and presumably in hospital admissions due to respiratory effects, too. Associations with increased daily mortality as well as with carcinogenicity and premature ageing of the lungs are under discussion. Groups at special risk are all persons exercising or working outdoors with increased ventilation; old persons don't seem to be a risk group. Ozone concentrations often exceed health-related guideline values. Legally binding limit values are problematic in the case of secondary pollutants like ozone. (orig.) [German] Ozon ist ein natuerlicher Bestandteil der Luft, dessen Konzentration durch anthropogene Aktivitaeten deutlich erhoeht ist. Als starkes Oxidationsmittel reizt es die Atemwege, in die es wegen seiner geringen Wasserloeslichkeit tief eindringen kann. Erhoehte Ozon-Konzentrationen fuehren zu einer Verschlechterung der Lungenfunktionswerte und zu einer Zunahme von Asthmaanfaellen und vermutlich auch von Krankenhausaufnahmen wegen Atemwegserkrankungen. Ob auch die taegliche Mortalitaet bei hohen Ozonbelastungen ansteigt, ist umstritten, ebenso wie eine moegliche krebserzeugende Wirkung und ein 'vorzeitiges Altern' der Lunge. Als Risikogruppen koennen alle Personen gelten, die ueber laengere Zeitraeume koerperlich anstrengende Taetigkeiten im Freien ausueben, Senioren gehoeren nicht dazu. Gesundheitsbezogene Richtlinie fuer Ozon werden haeufig ueberschritten. Rechtsverbindliche Grenzwerte sind fuer sekundaere Schadstoffe wie Ozon problematisch. (orig.)

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

    International Nuclear Information System (INIS)

    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

    Indian Academy of Sciences (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. Ambient intelligence

    CERN Document Server

    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)

  15. Ozone promotes regeneration by regulating the inflammatory response in zebrafish.

    Science.gov (United States)

    Hao, Kenan; Li, Yanhao; Feng, Jianyu; Zhang, Wenqing; Zhang, Yiyue; Ma, Ning; Zeng, Qingle; Pang, Huajin; Wang, Chunyan; Xiao, Lijun; He, Xiaofeng

    2015-09-01

    Ozone is thought to advance wound healing by inhibiting inflammation, but the mechanism of this phenomenon has not been determined. Although the zebrafish is often used in regeneration experiments, there has been no report of zebrafish treated with ozonated water. We successfully established a zebrafish model of ozonated water treatment and demonstrate that ozonated water stimulates the regeneration of the zebrafish caudal fin, its mechanism, and time dependence. The growth rate of the caudal fin and the number of neutrophils migrating to the caudal fin wound after resection were higher in the experimental (ozonated) group than in the control group, preliminarily confirming that ozone-promoted regeneration is related to the stimulation of an early inflammatory response by ozone. Ozone modulated the expression of tumor necrosis factor-? (TNF-?) in two ways by regulating interleukin 10 (IL-10) expression. Therefore, ozone promotes tissue regeneration by regulating the inflammatory pathways. This effect of ozone in an experimental zebrafish model is demonstrated for the first time, confirming its promotion of wound healing and the mechanism of its effect in tissue regeneration. These results will open up new directions for ozone and regeneration research. PMID:26033494

  16. Rapid increases in tropospheric ozone production and export from China

    Science.gov (United States)

    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.

  17. Ozone Antimicrobial Efficacy

    Science.gov (United States)

    Ozone is a potent germicide that has been used extensively for water purification. In Europe, 90 percent of the municipal water systems are treated with ozone, and in France, ozone has been used to treat drinking water since 1903. However, there is limited information on the bioc...

  18. Physiological and foliar injury responses of Prunus serotina, Fraxinus americana, and Acer rubrum seedlings to varying soil moisture and ozone

    International Nuclear Information System (INIS)

    High soil water availability favors ozone uptake, increases foliar injury, and exacerbates the negative ozone effect on gas exchange of seedlings of deciduous tree species. - Sixteen black cherry (Prunus serotina, Ehrh.), 10 white ash (Fraxinus americana, L.) and 10 red maple (Acer rubrum, L.) 1-year old seedlings were planted per plot in 1997 on a former nursery bed within 12 open-top chambers and six open plots. Seedlings were exposed to three different ozone scenarios (ambient air: 100% O3; non-filtered air: 98% ambient O3; charcoal-filtered air: 50% ambient O3) within each of two different water regimes (nine plots irrigated, nine plots non-irrigated) during three growing seasons. During the 1998 and 1999 growing season, leaf gas exchange, plant water relations, and foliar injury were measured. Climatic data, ambient- and chamber-ozone-concentrations were monitored. We found that seedlings grown under irrigated conditions had similar (in 1998) but significantly higher gas exchange rates (in 1999) than seedlings grown within non-irrigated plots among similar ozone exposures. Cherry and ash had similar ozone uptake but cherry developed more ozone-induced injury (<34% affected leaf area, LAA) than ash (<5% LAA), while maple rarely showed foliar injury, indicating the species differed in ozone sensitivity. Significantly more severe injury on seedlings grown under irrigated conditions than seedlings grown under non-irrigated conditions demonstrated that soil moisture altered seedling responses to ambient ozone exposures

  19. Physiological and foliar injury responses of Prunus serotina, Fraxinus americana, and Acer rubrum seedlings to varying soil moisture and ozone

    Energy Technology Data Exchange (ETDEWEB)

    Schaub, M.; Skelly, J.M.; Steiner, K.C.; Davis, D.D.; Pennypacker, S.P.; Zhang, J.; Ferdinand, J.A.; Savage, J.E.; Stevenson, R.E

    2003-07-01

    High soil water availability favors ozone uptake, increases foliar injury, and exacerbates the negative ozone effect on gas exchange of seedlings of deciduous tree species. - Sixteen black cherry (Prunus serotina, Ehrh.), 10 white ash (Fraxinus americana, L.) and 10 red maple (Acer rubrum, L.) 1-year old seedlings were planted per plot in 1997 on a former nursery bed within 12 open-top chambers and six open plots. Seedlings were exposed to three different ozone scenarios (ambient air: 100% O{sub 3}; non-filtered air: 98% ambient O{sub 3}; charcoal-filtered air: 50% ambient O{sub 3}) within each of two different water regimes (nine plots irrigated, nine plots non-irrigated) during three growing seasons. During the 1998 and 1999 growing season, leaf gas exchange, plant water relations, and foliar injury were measured. Climatic data, ambient- and chamber-ozone-concentrations were monitored. We found that seedlings grown under irrigated conditions had similar (in 1998) but significantly higher gas exchange rates (in 1999) than seedlings grown within non-irrigated plots among similar ozone exposures. Cherry and ash had similar ozone uptake but cherry developed more ozone-induced injury (<34% affected leaf area, LAA) than ash (<5% LAA), while maple rarely showed foliar injury, indicating the species differed in ozone sensitivity. Significantly more severe injury on seedlings grown under irrigated conditions than seedlings grown under non-irrigated conditions demonstrated that soil moisture altered seedling responses to ambient ozone exposures.

  20. AMBIENT AIR QUALITY AND SELECTED BIRTH DEFECTS, SEVEN COUNTY STUDY, TEXAS, 1997-2000

    Science.gov (United States)

    Background: A number of epidemiologic investigations have shown adverse effects of ambient air pollution on reproductive outcomes. A recent case-control study found associations betweensecond gestational month carbon monoxide and ozone exposure and elevated risks of selec...

  1. Estrés oxidativo en un modelo de ratón quemado tratado con Aloe b, ozono y factor de crecimiento epidérmico / Oxidative stress in a model of burnt mouse treated with Aloe b, ozone and epidermal growth factor

    Scientific Electronic Library Online (English)

    Teresita, Montero González; José, Hurtado de Mendoza Amat; José Carlos, García Piñeiro; Niurka A., Llopiz Janer; Silvia, Menéndez Cepero; Jorge, Berlanga Acosta.

    2006-09-01

    Full Text Available La enfermedad por quemadura estimula la respuesta inflamatoria sistémica y el daño múltiple de órganos, su expresión morfológica. Con el propósito de identificar el comportamiento del estrés oxidativo mediante el malondialdehído, la superóxido dismutasa y la catalasa y su modificación con el empleo [...] del tratamiento sistémico con Aloe b, ozono o factor de crecimiento epidérmico, se elaboró un modelo de quemadura seca de un área de 11 %, en ratones hembras, balb/c de 20 ± 2 g (n= 24). Se aplicó eutanasia en diferentes tiempos, se estudiaron los órganos con evaluación cualitativa en grados de intensidad y las variables bioquímicas se obtuvieron del riñón y del hígado. La prueba G se empleó para conocer la dependencia entre las variables y la prueba t se usó al comparar porcentajes. El análisis de varianza bifactorial y la prueba de rango múltiple de Duncan se empleó en las variables del estrés oxidativo estudiadas. Se siguieron las normas éticas en el trabajo con los animales. Existió dependencia entre los diferentes grupos y la vitalidad (G= 268,83***) superior en los grupos tratados. Los grupos no tratados tuvieron mayor intensidad del daño múltiple de órganos y peor respuesta del estrés oxidativo. Los grupos con mejor evolución fueron el tratado con ozono y el tratado con factor de crecimiento epidérmico. El tratamiento inmediatamente después de la quemadura con ozono y factor de crecimiento epidérmico resultó favorable para la evolución y supervivencia de los animales. Abstract in english Burn disease stimulates systemic inflammatory response and its morphologic expression that is multiple organ failure. With the objective of identifying the behaviour of oxidative stress through malonaldehyde, superoxide dismutase, and catalase, and its change by using the systemic treatment based on [...] Aloe b, ozone or epidermal growth factor, a dry burn model of a 11 % area in balb/c female mice of 20 ± 2 g (n= 24) was designed. Eutanasia was applied at different moments, organs were studied with qualitative evaluation of intensity degrees, and biochemical variables were analyzed from the kidney and the liver of mice. Test G served to find out dependence among variables and Test t was used to compare percentages. Bifactoral variance analysis and Duncan´s multiple range test were used in the studied oxidative stress variables. Ethical standards on work with animals were complied with. Dependence was observed among the various groups and survival rate (G= 268,83***) was higher in the treated groups. Untreated groups showed more intensive multiple organ damage and worse oxidative stress response. The groups treated with ozone and epidermal growth factor showed better recovery. The treatment with ozone and epidermal growth factor immediately after burning favored recovery and survival of balb/c mice.

  2. Estrés oxidativo en un modelo de ratón quemado tratado con Aloe b, ozono y factor de crecimiento epidérmico Oxidative stress in a model of burnt mouse treated with Aloe b, ozone and epidermal growth factor

    Directory of Open Access Journals (Sweden)

    Teresita Montero González

    2006-09-01

    Full Text Available La enfermedad por quemadura estimula la respuesta inflamatoria sistémica y el daño múltiple de órganos, su expresión morfológica. Con el propósito de identificar el comportamiento del estrés oxidativo mediante el malondialdehído, la superóxido dismutasa y la catalasa y su modificación con el empleo del tratamiento sistémico con Aloe b, ozono o factor de crecimiento epidérmico, se elaboró un modelo de quemadura seca de un área de 11 %, en ratones hembras, balb/c de 20 ± 2 g (n= 24. Se aplicó eutanasia en diferentes tiempos, se estudiaron los órganos con evaluación cualitativa en grados de intensidad y las variables bioquímicas se obtuvieron del riñón y del hígado. La prueba G se empleó para conocer la dependencia entre las variables y la prueba t se usó al comparar porcentajes. El análisis de varianza bifactorial y la prueba de rango múltiple de Duncan se empleó en las variables del estrés oxidativo estudiadas. Se siguieron las normas éticas en el trabajo con los animales. Existió dependencia entre los diferentes grupos y la vitalidad (G= 268,83*** superior en los grupos tratados. Los grupos no tratados tuvieron mayor intensidad del daño múltiple de órganos y peor respuesta del estrés oxidativo. Los grupos con mejor evolución fueron el tratado con ozono y el tratado con factor de crecimiento epidérmico. El tratamiento inmediatamente después de la quemadura con ozono y factor de crecimiento epidérmico resultó favorable para la evolución y supervivencia de los animales.Burn disease stimulates systemic inflammatory response and its morphologic expression that is multiple organ failure. With the objective of identifying the behaviour of oxidative stress through malonaldehyde, superoxide dismutase, and catalase, and its change by using the systemic treatment based on Aloe b, ozone or epidermal growth factor, a dry burn model of a 11 % area in balb/c female mice of 20 ± 2 g (n= 24 was designed. Eutanasia was applied at different moments, organs were studied with qualitative evaluation of intensity degrees, and biochemical variables were analyzed from the kidney and the liver of mice. Test G served to find out dependence among variables and Test t was used to compare percentages. Bifactoral variance analysis and Duncan´s multiple range test were used in the studied oxidative stress variables. Ethical standards on work with animals were complied with. Dependence was observed among the various groups and survival rate (G= 268,83*** was higher in the treated groups. Untreated groups showed more intensive multiple organ damage and worse oxidative stress response. The groups treated with ozone and epidermal growth factor showed better recovery. The treatment with ozone and epidermal growth factor immediately after burning favored recovery and survival of balb/c mice.

  3. Formation and emissions of carbonyls during and following gas-phase ozonation of indoor materials

    DEFF Research Database (Denmark)

    Poppendieck, D.G.; Hubbard, H.F.; Weschler, Charles J.; Corsi, R.L.

    2007-01-01

    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...

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

    Science.gov (United States)

    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,...

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

    Science.gov (United States)

    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...

  6. Earth's ozone layer

    International Nuclear Information System (INIS)

    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

  7. UV/ozone cleaning of surfaces

    Science.gov (United States)

    Vig, J. R.

    1986-05-01

    The UV/ozone methods, which is reviewed in this report, is an effective method of removing a variety of contaminants from surfaces. It is a simple-to-use dry process which is inexpensive to set up and operate. It can rapidly produce clean surfaces, in air or in a vacuum system, at ambient temperatures. Placing properly precleaned surface within a few millimeters of an ozone-producing UV source can produce clean surfaces in less than one minute. The technique can produce clean surfaces in less than one minute. The technique can produce near-atomically clean surfaces, as evidenced by Auger electron spectrosocpy (AES), electron spectroscopy for chemical analysis (ESCA), and ion scattering spectroscopy/secondary ion mass spectroscopy (ISS/SIMS) studies. Topics discussed include the variables of the process, the types for surfaces which have been cleaned successfully, the contaminants that can be removed, the construction of a UV ozone cleaning facility, the mechanism of the process, UV/ozone cleaning in vacuum systems, rate-enhancement techniques, safety consideration, effects of UV/ozone other than cleaning, and applications.

  8. Effect of in-package ozonation on quality of raw broiler breast meat during storage

    Science.gov (United States)

    In-package ozonation is an antimicrobial packaging system that uses atmospheric cold plasma technology to generate ozone and other gases inside a sealed package to inhibit microbial growth on packaged food. Previous unpublished research has shown that in-package ozonation effectively kills and inhib...

  9. Influence of Global Atmospheric Change on the Feeding Behavior and Growth Performance of a Mammalian Herbivore, Microtus ochrogaster

    OpenAIRE

    Habeck, Christopher W.; Lindroth, Richard L.

    2013-01-01

    Global atmospheric change is influencing the quality of plants as a resource for herbivores. We investigated the impacts of elevated carbon dioxide (CO2) and ozone (O3) on the phytochemistry of two forbs, Solidago canadensis and Taraxacum officinale, and the subsequent feeding behavior and growth performance of weanling prairie voles (Microtus ochrogaster) feeding on those plants. Plants for the chemical analyses and feeding trials were harvested from the understory of control (ambient air), ...

  10. Carbon and nitrogen allocation of juvenile and adult beech (Fagus sylvatica) and spruce (Picea abies) trees under contrasting ozone exposure and competition: a 13C/12C and 15N/14N labeling approach

    OpenAIRE

    Ritter, Wilma

    2011-01-01

    Chronically elevated tropospheric ozone (O3) concentrations are known to affect tree growth and competitiveness. Using the stable isotopes 13C and 15N as tracer, carbon and nitrogen allocation was studied in juvenile and adult beech (Fagus sylvatica) and spruce (Picea abies) trees that were exposed to twice-ambient O3 concentrations. Juvenile trees were, additionally, grown in mono- and mixed cultures to excamine intra- and interspecific competition effects. Investigations on saplings were ca...

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

    International Nuclear Information System (INIS)

    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

  12. Minor effects of long-term ozone exposure on boreal peatland species Eriophorum vaginatum and Sphagnum papillosum

    DEFF Research Database (Denmark)

    Mörsky, SK; Haapala, JK; Rinnan, Riikka; Saarnio, S; Silvola, J; Martikainen, PJ; Holopainen, T

    2011-01-01

    into the soil of an open-air experimental field for four growing seasons. The open-air ozone exposure field consists of eight circular plots of which four were fumigated with elevated ozone concentration (doubled ambient) and four were ambient controls. The results showed that E. vaginatum and S...

  13. Beneficial effects of CO2 enrichment to field-grown soybeans under ozone stress

    International Nuclear Information System (INIS)

    Damage from gaseous air pollution [e.g. ozone (O3) and sulfur dioxide (SO2)] on crops in the US has been estimated to exceed several billion dollars annually. Atmospheric carbon dioxide (CO2) concentrations have increased from about 290 ppm in the late 1800's to current levels of 350 ppm. The combined effects of increased CO2 and O3 stress have not been studied under field conditions. The present study was conducted to determine the interactive effects of CO2 enrichment and O3 stress on the growth and physiology of 'Clark' soybean, testing the hypothesis that elevated CO2 will ameliorate the effects of O3 stress. Experiments with soybeans in open-top field chambers showed that increasing CO2levels to 400 parts per million (ppm) negated current ambient ozone harmful effects on soybean yields. When ambient O3 levels were doubled, it was necessary to increase the atmospheric CO2 concentration to 500 ppm to negate O3 damage. Rising CO2 counteracts O3 pollution. Reduced stomatal conductance and decreased photosynthesis appear to reverse the CO2 stimulation

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

    International Nuclear Information System (INIS)

    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)

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

    Science.gov (United States)

    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

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

    DEFF Research Database (Denmark)

    Nielsen, Birte Lindstrøm

    2012-01-01

    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...... to adapt to cooler ambient temperatures....

  17. Use of ozone to reduce molds in a cheese ripening room

    OpenAIRE

    Serra, Rita; Abrunhosa, Luís; Kozakiewicz, Z.; Venâncio, Armando; Lima, Nelson

    2003-01-01

    Cheese ripening rooms have an unusual environment, an environment that encourages mold growth. Ozone has been applied in various ways in the food industry. One useful advantage of ozone is that it inactivates molds. In this study, a cheese ripening room was ozonated, and the effectiveness of this treatment was evaluated both in air and on surfaces through sampling on a weekly basis over a 3-month period. The results obtained indicate that ozone treatment reduced the viable airborne mold load ...

  18. Intercontinental trans-boundary contributions to ozone-induced crop yield losses in the Northern Hemisphere

    OpenAIRE

    M. J. Hollaway; Arnold, S. R.; A. J. Challinor; Emberson, L. D.

    2011-01-01

    Enhanced surface ozone concentrations are known to be harmful to vegetation, reducing crop growth and yields. Tropospheric ozone concentrations have increased steadily since pre-industrial times, driven by in-situ production from anthropogenic emissions of nitrogen oxides (NOx), CO and volatile organic compounds. Transport of ozone and its precursors between continents has been shown to contribute to surface ozone air quality exceedences in many regions of the Northern ...

  19. Measurement of Ground Level Ozone at Different Locations

    Directory of Open Access Journals (Sweden)

    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-Zaâ??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-Zaâ??afarania area at 12: PM, 1: PM, 2: PM and 3: PM and in Al-Dora at 2: PM.

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

    International Nuclear Information System (INIS)

    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

  1. Industrial emissions cause extreme urban ozone diurnal variability

    OpenAIRE

    Zhang, Renyi; Lei, Wenfang; Tie, Xuexi; Hess, Peter

    2004-01-01

    Simulations with a regional chemical transport model show that anthropogenic emissions of volatile organic compounds and nitrogen oxides (NOx = NO + NO2) lead to a dramatic diurnal variation of surface ozone (O3) in Houston, Texas. During the daytime, photochemical oxidation of volatile organic compounds catalyzed by NOx results in episodes of elevated ambient O3 levels significantly exceeding the National Ambient Air Quality Standard. The O3 production rate in Houston is significantly higher...

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

    Directory of Open Access Journals (Sweden)

    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 on ozone concentration with others based on ozone flux models.

  3. Desempenho e orientação do crescimento do pepino japonês em ambiente protegido / Performance and growth conduction of Japanese cucumber in protected environment

    Scientific Electronic Library Online (English)

    Adalberto, Santi; Walcylene LMP, Scaramuzza; Danilo MJ, Soares; José Fernando, Scaramuzza; Rivanildo, Dallacort; Willian, Krause; Rafael Cesar, Tieppo.

    2013-12-01

    Full Text Available Avaliou-se a produção de pepino japonês Tsuyataro, com diferentes métodos de orientação do crescimento das hastes, a partir do controle de brotações laterais das hastes e do número de hastes por planta, realizados através da poda. O trabalho foi desenvolvido no período de outubro a dezembro de 2010, [...] em ambiente protegido em Tangará da Serra-MT, adotando-se o delineamento em blocos casualizados, distribuídos em esquema fatorial 2x3. O primeiro fator foi constituído de desbrota, ou seja, realização ou não da retirada dos ramos laterais das hastes e o segundo fator foi constituído pelo controle do número de hastes por planta: uma, duas e três hastes/planta, em cinco repetições. Foram avaliadas as características número de frutos total e comercial; taxa de frutos comerciais, comprimento, diâmetro, relação comprimento/diâmetro do fruto, produtividade total e comercial de frutos por planta; e massa média dos frutos do pepino. A condução da haste principal sem a retirada dos ramos laterais foi o tratamento que apresentou superioridade com relação ao número de frutos total e comercial por planta (19,4 e 16,0), e também maior produtividade total e comercial de frutos (4.235,8 e 3.438,3 g/planta). Já a poda das brotações laterais promoveu aumento no comprimento, diâmetro e na massa média dos frutos do pepino de 24,5 para 25,1 cm; 3,4 para 3,5 cm e 212,1 para 228,3 g/fruto, respectivamente. Abstract in english The production of the Japanese cucumber Tsuyataro was evaluated using methods of stems growth conduction, controlling the lateral buds and number of stems per plant, through pruning. The research was carried out from October to December 2010, in a protected environment in Tangará da Serra, Mato Gros [...] so state, Brazil, using a randomized blocks design, with five replications, in a factorial scheme (2x3). The first factor was the pruning, i.e., removal or not of lateral stems and the second factor was constituted of the control of number of stems: one, two and three stems per plant, with five replications. We evaluated the following characteristics: total and marketable number of fruits, commercial fruits rate, fruit length, fruit diameter, fruit length/diameter ratio, total and marketable yield of fruit per plant and fruit average weight. The treatment with conduction of the main stem without removal of lateral buds had better performance on total and marketable number of fruits per plant (19.4 and 16.0) and higher total and marketable yield of fruits (4,235.8 and 3,438.3 g per plant). The pruning of lateral buds provided increase in length, diameter and average mass of cucumber fruits of 24.5 to 25.1 cm; 3.4 to 3.5 cm and 212.1 to 228.3 g per fruit, respectively.

  4. Crescimento do pinhão-manso irrigado com águas salinas em ambiente protegido / Growth of Jatropha irrigated with saline water in greenhouse

    Scientific Electronic Library Online (English)

    Aparecida R., Nery; Luis N., Rodrigues; Maria B. R., Silva; Pedro D., Fernandes; Lúcia H. G., Chaves; José, Dantas Neto; Hans R., Gheyi.

    2009-10-01

    Full Text Available Considerando as potencialidades de uso do pinhão manso (Jatropha curcas L.) como fonte energética e a carência de resultados de pesquisa relativos ao seu cultivo, realizou-se este trabalho com o fim primordial de se estudar os efeitos da salinidade da água de irrigação sobre o crescimento das planta [...] s, em ambiente protegido. A pesquisa foi desenvolvida entre abril e outubro de 2007, no Centro de Tecnologia e Recursos Naturais (CTRN) da UFCG-PB. As plantas foram cultivadas em lisímetros de drenagem (200 L), contendo 230 kg de material de solo devidamente adubado, não-salino, não-sódico, classificado como Argissolo Acinzentado eutrófico. Os tratamentos consistiram de cinco níveis de condutividade elétrica da água de irrigação - CEa (0,6; 1,2; 1,8; 2,4 e 3,0 dS m-1, a 25 ºC), no delineamento experimental em blocos casualizados, com quatro repetições, sendo cada parcela constituída pela média de duas plantas cultivadas em lisímetros separados. Avaliaram-se altura de planta, diâmetro caulinar, número de folhas e área foliar aos 37, 58, 79, 100, 121, 142 e 163 dias após a semeadura; ao final do período de estudos, o pinhão-manso irrigado com água de CEa de 3,0 dS m-1 teve a altura de planta, o diâmetro caulinar, o número de folhas e a área foliar reduzidos em 9,07, 17,63, 23,41 e 42,58%, respectivamente. Abstract in english The objective of this work was to evaluate the effects of irrigation water salinity on the growth of Jatropha curcas L. in greenhouse. The research was carried out during April and October of 2007, in a greenhouse of the Department of Agricultural Engineering of the Natural Resources and Technology [...] Center (CTRN) of Federal University of Campina Grande, Paraíba, Brazil. The plants were grown in drainage lysimeters (200 L) with 230 kg of non-saline, non-sodic soil adequately fertilized, classified as Gray Argisol eutrophic. The treatments consisted of five levels of electrical conductivity of the irrigation water - CEw (0.6, 1.2, 1.8, 2.4 and 3.0 dS m-1, at 25 ºC). The experimental design was in randomized blocks with 4 replications, each replication represented by the average of 2 plants cultivated in separate lysimeters. Plant height, stem diameter, number of leaves and leaf area were evaluated at 37, 58, 79, 100, 121, 142 and 163 days after sowing (DAS). At 163 DAS, Jatropha irrigated with ECw equal to 3.0 dS m-1 had plant height, stem diameter, number of leaves and leaf area reduced by 9.07, 17.63, 23.41 and 42.58%, respectively.

  5. Crescimento do pinhão-manso irrigado com águas salinas em ambiente protegido Growth of Jatropha irrigated with saline water in greenhouse

    Directory of Open Access Journals (Sweden)

    Aparecida R. Nery

    2009-10-01

    Full Text Available Considerando as potencialidades de uso do pinhão manso (Jatropha curcas L. como fonte energética e a carência de resultados de pesquisa relativos ao seu cultivo, realizou-se este trabalho com o fim primordial de se estudar os efeitos da salinidade da água de irrigação sobre o crescimento das plantas, em ambiente protegido. A pesquisa foi desenvolvida entre abril e outubro de 2007, no Centro de Tecnologia e Recursos Naturais (CTRN da UFCG-PB. As plantas foram cultivadas em lisímetros de drenagem (200 L, contendo 230 kg de material de solo devidamente adubado, não-salino, não-sódico, classificado como Argissolo Acinzentado eutrófico. Os tratamentos consistiram de cinco níveis de condutividade elétrica da água de irrigação - CEa (0,6; 1,2; 1,8; 2,4 e 3,0 dS m-1, a 25 ºC, no delineamento experimental em blocos casualizados, com quatro repetições, sendo cada parcela constituída pela média de duas plantas cultivadas em lisímetros separados. Avaliaram-se altura de planta, diâmetro caulinar, número de folhas e área foliar aos 37, 58, 79, 100, 121, 142 e 163 dias após a semeadura; ao final do período de estudos, o pinhão-manso irrigado com água de CEa de 3,0 dS m-1 teve a altura de planta, o diâmetro caulinar, o número de folhas e a área foliar reduzidos em 9,07, 17,63, 23,41 e 42,58%, respectivamente.The objective of this work was to evaluate the effects of irrigation water salinity on the growth of Jatropha curcas L. in greenhouse. The research was carried out during April and October of 2007, in a greenhouse of the Department of Agricultural Engineering of the Natural Resources and Technology Center (CTRN of Federal University of Campina Grande, Paraíba, Brazil. The plants were grown in drainage lysimeters (200 L with 230 kg of non-saline, non-sodic soil adequately fertilized, classified as Gray Argisol eutrophic. The treatments consisted of five levels of electrical conductivity of the irrigation water - CEw (0.6, 1.2, 1.8, 2.4 and 3.0 dS m-1, at 25 ºC. The experimental design was in randomized blocks with 4 replications, each replication represented by the average of 2 plants cultivated in separate lysimeters. Plant height, stem diameter, number of leaves and leaf area were evaluated at 37, 58, 79, 100, 121, 142 and 163 days after sowing (DAS. At 163 DAS, Jatropha irrigated with ECw equal to 3.0 dS m-1 had plant height, stem diameter, number of leaves and leaf area reduced by 9.07, 17.63, 23.41 and 42.58%, respectively.

  6. Ozone studies in the Paso del Norte region

    Science.gov (United States)

    Becerra-Davila, Fernando

    The Paso del Norte region forms the largest contiguous bi-national conglomerate on the US-Mexico border. With a combined population of around 2 million inhabitants, the Paso del Norte region is isolated, more than 500 km away from the nearest urban area of comparable size, thus making it an ideal location for air quality studies of an isolated urban environment. The meteorological conditions leading to a high ozone episode in this region, such as the historical ozone episode of June 2006, are analyzed. It is well known that stagnation and minimal winds, high temperatures, and pressure ridges over the region are conducive to high ozone episodes. In addition, the planetary boundary height is studied to understand its impact on high ozone episodes. Several studies report that ground level ozone non-attainment regulations could be caused not only by local emissions, but also by atmospheric transport. In this work the atmospheric advection of pollutants into the region is analyzed using HYSPLIT backward trajectories. Furthermore, a novel backward trajectory clustering technique is implemented for the summer of 2006. The "ozone weekend effect" (OWE) is a phenomenon by which in some geographical regions ambient ozone concentrations tend to be higher on weekends than on weekdays, despite the lower emissions of ozone precursors during those days. The observed local OWE has never previously been studied in terms of the photolysis rates of four of the main ozone precursors. In this research a novel method that allows the calculation of actinic fluxes, photolysis frequencies and photolysis rates with a high degree of accuracy and reliability has been developed. This method utilizes a combination of the experimental data available for this region in conjunction with a radiative transfer model (TUV model). Three weekend-weekday cases during summers 2006, 2009 and 2010 are studied in this work. In this research, the photolysis impact on the local OWE is studied. The results obtained from this photolysis study demonstrate that the local ground level ozone formation is not only influenced by the strong solar radiation and changing aerosol makeup, but also by other heterogeneous factors and reactions. In addition, this research provided good evidence that the ground level ozone precursor regime in El Paso during the ozone episode of June 2006 was mostly VOC-limited. Much of this estimation was derived from measurements of local ambient VOC/NOx ratios. This finding shows that at least during June 2006, the non-linear surface ozone production increased during weekends compared to workdays in a habitually VOC-limited regime. The seasonal variations of columnar ozone as measured by a Multi-filter Rotating Shadowband instrument installed at the UTEP campus are analyzed for the first time for this region and results are presented. This investigation has addressed the problem of ground-level ozone formation in the Paso del Norte region. Urban ozone is a complex problem with many aspects that are not fully understood. In this investigation, a range of techniques has been used to address the study of local surface ozone episodes with the purpose of acquiring new insights and knowledge that will help understand and remediate the diverse atmospheric pollution events that affect this bi-national region recurrently. Innovative techniques were developed and used, ranging from the use of local ambient atmospheric pollution data to the utilization of complex modeling techniques to achieve the best possible computer results. Finally, the influence of ground level ozone concentrations in admissions to hospitals for this region due to respiratory diseases is analyzed. The comprehensive results obtained in this work will help to better understand ozone formation in the Paso del Norte Region for future policy regulation implementations.

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

    Science.gov (United States)

    Ran, Liang; Zhao, Chunsheng

    2013-04-01

    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. High ozone concentrations (>80 ppbv) of long duration (>6h) were frequently encountered in both urban and suburban Tianjin, while the occurrence of high ozone concentrations lasted for a shorter period (usually 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.

  8. barrido ambiental

    Directory of Open Access Journals (Sweden)

    Rosario Neri Basurto

    2008-01-01

    Full Text Available El casco es una estructura relativamente sencilla, constituida por queratina, proteína bastante sulfatada, que provee al casco de dureza y cierta elasticidad para soportar el peso y distribuir la intensidad del impacto en el casco. Para este fi n, se necesita que el casco tenga una calidad adecuada, que requiere de buena nutrición basada en proteínas, vitaminas y minerales. Los minerales constituyen 4% del peso corporal y se conforman en macrominerales (calcio, fósforo, sodio, cloro, potasio, magnesio y azufre y microminerales (selenio, yodo, cobre y zinc. El zinc participa en la formación del casco al inducir la producción de queratina. Su defi ciencia en la dieta causa problemas al tejido córneo, como cascos delgados, friables y fi suras en la pared. Para que el Zn++ sea absorbido adecuadamente, es necesario que sea ingerido en forma quelada como metionina de zinc. La dieta de siete caballos fue complementada con 5.4 g/día/caballo de metionina de zinc por un periodo de seis meses. Se obtuvieron muestras a nivel de la muralla y se realizaron cortes transversales; antes y después del tratamiento, se analizó su morfología y contenido de minerales (Mg++, Cl-, S, Ca++, Na++, K+, P, Si, Fe++, Cu++, Zn++ en el microscopio electrónico de barrido ambiental equipado con dispersor de rayos X. Se observó que la morfología presentaba mejor constitución y compactación de los cuernos tubulares e intratubulares en el estrato medio, así como aumento sustancial de zinc (32.9% y de azufre (68.4%, lo cual sugiere incremento de queratina y mejor estructuración del casco

  9. The stratospheric ozone and the ozone layer

    International Nuclear Information System (INIS)

    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

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

    OpenAIRE

    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...

  11. Ambient air pollution and the fetus

    OpenAIRE

    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...

  12. Effects of elevated ground-level ozone on nitrogen acquisition of mature European beech (Fagus sylvatica) and Norway spruce (Picea abies) trees

    OpenAIRE

    Weigt, Rosemarie Barbara

    2011-01-01

    Chronically elevated ground-level ozone (O3) concentrations are known to affect tree growth and may alter nutrient supply. Using the stable isotope 15N as tracer, the nitrogen(N)-uptake and allocation was studied in ca. 60 yr old beech (Fagus sylvatica) and spruce (Picea abies) that were exposed to twice-ambient O3 concentrations over 7 years. A slight reduction in N acquisition was evident in both species along with a slight increase in N demand (particularly in spruce). The reduction in N u...

  13. Artificial ozone holes

    OpenAIRE

    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...

  14. INFLUENCE OF OZONE ON PENTOBARBITAL PHARMACOKINETICS IN MICE

    Science.gov (United States)

    It had been shown that 3 to 5 hr exposures to ambient concentrations of ozone (O3) increase pentobarbital-induced sleeping time in female mice, hamsters, and rats without decreasing heptatic cytochrome P-450 levels or selected mixed function oxidases. To elucidate potential mecha...

  15. Sites of ozone sensitivity in diverse maize inbred lines

    Science.gov (United States)

    Tropospheric ozone (O3) is an air pollutant that costs ~$14-26 billion in global crop losses and is projected to worsen in the future. Potential sites of O3 sensitivity in maize were tested by growing 200 inbred lines, including the nested association mapping population founder lines, under ambient...

  16. YIELD RESPONSE OF HEAD LETTUCE ('LACTUCA SATIVA' L.) TO OZONE

    Science.gov (United States)

    Head lettuce (Lactuca sativa L. cv 'Empire') was grown in the field and exposed in open-top chambers to proportional increments of ozone (O3) from full charcoal filtration (CF) to twice ambient O3 concentrations(NF x 2.0). Severe foliar injury developed on young plants exposed to...

  17. The origin of ozone

    OpenAIRE

    Grewe, V.

    2006-01-01

    Highest atmospheric ozone production rates can be found at around 30 km in the tropical stratosphere, leading to ozone mixing ratios of about 10 ppmv. Those stratospheric air masses are then transported to extra-tropical latitudes via the Brewer-Dobson circulation. This is considered the main mechanism to generate mid- and high latitude ozone. By applying the climate-chemistry models E39/C and MAECHAM4/CHEM, this view is investigated in more detail. The origin of ozone in the troposphere and ...

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

    DEFF Research Database (Denmark)

    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 concentration. The experiment was conducted during 70 days during the autumn. Our system could not detect any ozone effects on dark respiration, but eventually effects on dark respiration could be masked in signal noise. An inhibition of daily net photosynthesis in ozone treated shoots was apparent, and it is 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.

  19. Performances of diffusion tubes for the measurement of ozone, nitrogen dioxide and sulfur dioxide in ambient air; Performances des tubes a diffusion pour la mesure de l'ozone, du dioxyde d'azote et du dioxyde de soufre dans l'air ambiant

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Fouque, S.; Plansance, H.; Houdret, J.L.; Mathe, F.; Galloo, J.C.; Guillermo, R. [Ecole des Mines de Douai, 59 (France). Dept. Chimie et Environnement

    1999-09-01

    Diffusion tube is a simple device of measurement often used, in particular by networks of air quality monitoring, to analyse the spatial distribution of a pollutant on a city. It constitutes a good complement to the continuous monitoring with monitors. This article presents methods using diffusion tubes for the measurements of O{sub 3}, NO{sub 2} and SO{sub 2} in ambient air. Performances of these tubes: detection limit, accuracy, repeatability, and estimation of the error of measures are evaluated and discussed. With the long sampling times (in our study two weeks for SO{sub 2} and NO{sub 2}, and one week for O{sub 3}), these samplers present sufficiently low detection limits (DL < 5 {mu}g.m{sup -3}) to perform measurements of these three pollutants in ambient air. These methods give good repeatability (RSD{sub mean} {approx_equal} 5 %) for NO{sub 2} and O{sub 3}, and medium for SO{sub 2} (RSD{sub mean} {approx_equal} 12 %). Then diffusion tubes are validated on site by comparing their measures to those of the continuous monitors (techniques of reference). The good linearity has been checked between the tubes responses and the contents measured by monitors, the corresponding correlation coefficients are close to 0.9 for the three pollutants. The analysis of measure differences obtained between these two techniques has allowed to estimate errors of measures of diffusion tubes ({+-} 5 {mu}g.m{sup -3} for NO{sub 2}, {+-} 6 {mu}g/m{sup 3} for SO{sub 2} and {+-} 15 {mu}g.m{sup -3} for O{sub 3}). It seems us important to take into consideration these errors for interpretation of map air pollution levels obtained with diffusion tubes. (authors)

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

    International Nuclear Information System (INIS)

    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 ?g/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

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

    International Nuclear Information System (INIS)

    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

  2. Digestive utilization of ozone-exposed forage by rabbits (Oryctolagus cuniculus)

    Science.gov (United States)

    A mixture of common Southern Piedmont (USA) grassland species (Lolium arundinacea, Paspalum dilatatum, Cynodon dactylon and Trifolium repens) was exposed to ozone [ambient (non-filtered; NF) and twice-ambient (2X) concentrations] and fed to individually caged New Zealand white rabbits (Oryctolagus c...

  3. Ozone, area social conditions, and mortality in Mexico City

    International Nuclear Information System (INIS)

    We investigated whether the association of daily mortality and ambient ozone differs by age and area social conditions of the region of residence using a time-series analysis. The study setting was metropolitan Mexico City, a high altitude city situated in a valley, with an estimated 20 million inhabitants, large socioeconomic gradients, and ozone levels frequently exceeding international standards. We stratified daily deaths by six census-derived socioeconomic indicators, based on characteristics of the county where decedents lived. We used Poisson regression to model the association between daily mortality and ozone levels (on the day of death and the previous day) in separate models, stratified by area socioeconomic level and age, and controlling for time trends and temperature. Ozone was positively associated with total mortality [0.65% increase per 10 ppb increment, 95% confidence interval (CI): 0.02%, 1.28%] and for mortality among those over age 65 [1.39% increase per 10 ppb increment, 95% CI: 0.51%, 2.28%]. Associations between ozone and all-age mortality did not show any consistent patterns according to socioeconomic gradients. We conclude that elderly people are at higher risk for ozone-associated mortality. Though county-level social indicators in Mexico City were not strong markers of vulnerability to ozone-associated acute mortality in this analysis, complex associations between individual and area-level factors may exist that would require additional data and further analyses to elucidate

  4. Short-term effects of multiple ozone metrics on daily mortality in a megacity of China.

    Science.gov (United States)

    Li, Tiantian; Yan, Meilin; Ma, Wenjun; Ban, Jie; Liu, Tao; Lin, Hualiang; Liu, Zhaorong

    2015-06-01

    Epidemiological studies have widely demonstrated association between ambient ozone and mortality, though controversy remains, and most of them only use a certain metric to assess ozone levels. However, in China, few studies have investigated the acute effects of ambient ozone, and rare studies have compared health effects of multiple daily metrics of ozone. The present analysis aimed to explore variability of estimated health effects by using multiple temporal ozone metrics. Six metrics of ozone, 1-h maximum, maximum 8-h average, 24-h average, daytime average, nighttime average, and commute average, were used in a time-series study to investigate acute mortality associated with ambient ozone pollution in Guangzhou, China, using 3 years of daily data (2006-2008). We used generalized linear models with Poisson regression incorporating natural spline functions to analyze the mortality, ozone, and covariate data. We also examined the association by season. Daily 1- and 8-h maximum, 24-h average, and daytime average concentrations yielded statistically significant associations with mortality. An interquartile range (IQR) of O3 metric increase of each ozone metric (lag 2) corresponds to 2.92 % (95 % confidence interval (CI) 0.24 to 5.66), 3.60 % (95 % CI, 0.92 to 8.49), 3.03 % (95 % CI, 0.57 to 15.8), and 3.31 % (95 % CI, 0.69 to 10.4) increase in daily non-accidental mortality, respectively. Nighttime and commute metrics were weakly associated with increased mortality rate. The associations between ozone and mortality appeared to be more evident during cool season than in the warm season. Results were robust to adjustment for co-pollutants, weather, and time trend. In conclusion, these results indicated that ozone, as a widespread pollutant, adversely affects mortality in Guangzhou. PMID:25572272

  5. The Antarctic Ozone Hole.

    Science.gov (United States)

    Stolarski, Richard S.

    1988-01-01

    Discusses the Airborne Antarctic Ozone Experiment (1987) and the findings of the British Antarctic Survey (1985). Proposes two theories for the appearance of the hole in the ozone layer over Antarctica which appears each spring; air pollution and natural atmospheric shifts. Illustrates the mechanics of both. Supports worldwide chlorofluorocarbon…

  6. The pollution by ozone

    International Nuclear Information System (INIS)

    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.)

  7. Ozone isotopes retrievals

    OpenAIRE

    Piccolo, C.; Dudhia, A; Payne, V; Urban, J.; Murtagh, D.

    2005-01-01

    The isotopic ratios of stratospheric ozone can be used as valuable tracers for many processes in the atmosphere. Here we compare stratospheric enrichments of heavy ozone obtained from two limb sounders: MIPAS (Michelson Interferometer for Passive Atmospheric Sounding), on board Envisat, SMR (Sub-Millimetre Radiometer), on board the Odin satellite.

  8. Saving Our Ozone Shield.

    Science.gov (United States)

    Lacoste, Beatrice

    1992-01-01

    Discusses the introduction and continued use of chlorofluorocarbons (CFCs) as related to stratospheric ozone depletion. Presents the characteristics of CFCs conducive to the chemical reaction with ozone, the history of CFC use and detection of related environmental problems, health hazards, and alternatives to CFC use. (MCO)

  9. Ambient air pollution and low birthweight

    DEFF Research Database (Denmark)

    Pedersen, Marie; Giorgis-Allemand, Lise; Bernard, Claire; Aguilera, Inmaculada; Andersen, Anne-Marie Nybo; Ballester, Ferran; Beelen, Rob M J; Chatzi, Leda; Cirach, Marta; Danileviciute, Asta; Dedele, Audrius; Eijsden, Manon van; Estarlich, Marisa; Fernández-Somoano, Ana; Fernández, Mariana F; Forastiere, Francesco; Gehring, Ulrike; Grazuleviciene, Regina; Gruzieva, Olena; Heude, Barbara; Hoek, Gerard; de Hoogh, Kees; van den Hooven, Edith H; Håberg, Siri E; Jaddoe, Vincent W V; Klümper, Claudia; Korek, Michal; Krämer, Ursula; Lerchundi, Aitana; Lepeule, Johanna; Nafstad, Per; Nystad, Wenche; Patelarou, Evridiki; Porta, Daniela; Postma, Dirkje; Raaschou-Nielsen, Ole; Rudnai, Peter; Sunyer, Jordi; Stephanou, Euripides; Sørensen, Mette; Thiering, Elisabeth; Tuffnell, Derek; Varró, Mihály J; Vrijkotte, Tanja G M; Wijga, Alet; Wilhelm, Michael; Wright, John; Nieuwenhuijsen, Mark J; Pershagen, Göran; Brunekreef, Bert; Kogevinas, Manolis; Slama, Rémy

    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...... air pollutants and traffic during pregnancy is associated with restricted fetal growth. A substantial proportion of cases of low birthweight at term could be prevented in Europe if urban air pollution was reduced. FUNDING: The European Union....

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

    International Nuclear Information System (INIS)

    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.

  11. Antarctic ozone hole compared with arctic ozone behaviour

    International Nuclear Information System (INIS)

    Data, characterizing the formation of an ozone hole in the Antarctic Continent are discussed. The ozone hole is a reduction of the total content of ozone in the atmosphere from 300 Dobson units (D.u.) during the International geophysical year (1957-1958) to 120 D.u. in September-October, 1987. In 1988 the content of ozone in the region of the ozone hole grew notably: up to 210 D.u. Any phenomenon, similar to the ozone hole, was not observed in the Arctic Region. The main factors, facilitating the formation of an ozone hole, include low temperatures, polar stratospheric clouds and solar radiation

  12. Crops' responses to ozone in Mediterranean environments

    International Nuclear Information System (INIS)

    The Mediterranean environment, and most of the Italian peninsula, presents some peculiarities in terms of crop response to O3 since most physiological mechanisms activated upon O3 exposure, such as stomatal closure, often overlap and interact with those that underlie plant adaptation to drought and hyperosmotic stress, which are typical of these environments. OTC and EDU experiments have demonstrated that O3 causes strong yield losses when crops are grown without water limitations. However, exposure to water or saline stress significantly reduced O3 effects on crop yield. In this review, we present the methodological approaches that have been used to study plant-ozone interactions in Italy as well as biochemical, physiological and agronomic responses for representative cropping systems of the Mediterranean climate. - Is the 22% yield loss due to ambient ozone in non-limiting water conditions a realistic estimate for moderately stressed crops, typical of most Mediterranean regions?

  13. The Hole in the Ozone Layer.

    Science.gov (United States)

    Hamers, Jeanne S.; Jacob, Anthony T.

    This document contains information on the hole in the ozone layer. Topics discussed include properties of ozone, ozone in the atmosphere, chlorofluorocarbons, stratospheric ozone depletion, effects of ozone depletion on life, regulation of substances that deplete the ozone layer, alternatives to CFCs and Halons, and the future of the ozone layer.…

  14. Physiological and foliar injury responses of Prunus serotina, Fraxinus americana, and Acer rubrum seedlings to varying soil moisture and ozone.

    Science.gov (United States)

    Schaub, M; Skelly, J M; Steiner, K C; Davis, D D; Pennypacker, S P; Zhang, J; Ferdinand, J A; Savage, J E; Stevenson, R E

    2003-01-01

    Sixteen black cherry (Prunus serotina, Ehrh.), 10 white ash (Fraxinus americana, L.) and 10 red maple (Acer rubrum, L.) 1-year old seedlings were planted per plot in 1997 on a former nursery bed within 12 open-top chambers and six open plots. Seedlings were exposed to three different ozone scenarios (ambient air: 100% O3; non-filtered air: 98% ambient O3; charcoal-filtered air: 50% ambient O3) within each of two different water regimes (nine plots irrigated, nine plots non-irrigated) during three growing seasons. During the 1998 and 1999 growing season, leaf gas exchange, plant water relations, and foliar injury were measured. Climatic data,ambient- and chamber-ozone-concentrations were monitored. We found that seedlings grown under irrigated conditions had similar (in 1998) but significantly higher gas exchange rates (in 1999) than seedlings grown within non-irrigated plots among similar ozone exposures. Cherry and ash had similar ozone uptake but cherry developed more ozone-induced injury (< 34% affected leaf area, LAA) than ash (<5% LAA), while maple rarely showed foliar injury, indicating the species differed in ozone sensitivity. Significantly more severe injury on seedlings grown under irrigated conditions than seedlings grown under non-irrigated conditions demonstrated that soil moisture altered seedling responses to ambient ozone exposures. PMID:12713930

  15. Ozone as an air pollutant

    DEFF Research Database (Denmark)

    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....

  16. Application of Ozone in Medicine

    OpenAIRE

    Rakovsky, Slavcho; Zaikov, Gennady

    2009-01-01

    ? ?????? ???????? ???????????? ????? ? ???????? ? ???? ????? ?? ???????? ????????. ???????? ????? ?????????? ????????????? ????????????, ????????????? ????? ? ???????? ????????????. ????????? ????? ????????? ?????? ????? ?? ????? ?????? ? ??????? ??????. ?????????? ??????????? ?????. ????????, ?? ???? ???? ??????????????? ?? ????????????? ????? ? ??????????????, ??????????? ? ???????? ?????????????.This review deals with the application of ozone in medicine, its effect...

  17. Ozone laminae and teleconnection patterns.

    Czech Academy of Sciences Publication Activity Database

    Križan, Peter; Laštovi?ka, Jan; Krzyšcin, J. W.

    Athens : International Ozone Commission, 2004 - (Zerefos, C.), s. 421-422 ISBN 960-630-103-6. [Quadrennial Ozone Symposium /20./. Kos (GR), 01.06.2004-08.06.2004] Grant ostatní: CANDIDOZ(XE) EVK2-2001-00024 Institutional research plan: CEZ:AV0Z3042911 Keywords : ozone profile * ozone laminae Subject RIV: DG - Athmosphere Sciences, Meteorology

  18. Ozone and nitrogen effects on yield and nutritive quality of the annual legume Trifolium cherleri

    Science.gov (United States)

    Sanz, J.; González-Fernández, I.; Calvete-Sogo, H.; Lin, J. S.; Alonso, R.; Muntifering, R.; Bermejo, V.

    2014-09-01

    Two independent experiments were performed in an Open-Top Chamber facility to determine the response of biomass and nutritive quality of the annual legume Trifolium cherleri to increased levels of ozone (O3) and nitrogen (N) deposition, two main drivers of global change. Plants growing in pots were exposed to three O3 treatments: charcoal-filtered air (CFA); non-filtered air, reproducing ambient O3 levels of the site (NFA); and non-filtered air supplemented with 40 nl l-1 (NFA+). Nitrogen was added in biweekly doses to achieve final doses of 5 (N5), 15 (N15) and 30 kg ha-1 (N30), reproducing the N deposition range in the Iberian Peninsula. Ozone negatively affected all the growth-related parameters and increased plant senescent biomass. The pollutant affected subterranean biomass to a greater extent than aerial biomass, resulting in altered aerial/subterranean ratio. Effects in the second experiment followed the same pattern as in the first, but were of lesser magnitude. However, these differences between assays could not be explained adequately by the absorbed O3 fluxes (Phytotoxic Ozone Dose, POD). Concentrations of cell-wall constituents related to nutritive quality increased with the O3 exposure, reducing the Relative Food Value index (RFV) that indicates decreased nutritive quality of the forage. Nitrogen stimulated all growth-related parameters, but increased the aboveground biomass more than the subterranean biomass. No effects of N fertilizer were detected for the nutritive quality parameters. A significant interaction between O3 and N was found in the second experiment. N further enhanced the increase of senescent biomass caused by O3. Results indicate that O3 is a potentially significant environmental stress factor in terms of structure and diversity of Mediterranean pastures.

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

    International Nuclear Information System (INIS)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    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. Light environment alters ozone uptake per net photosynthetic rate in black cherry trees.

    Science.gov (United States)

    Fredericksen, T S; Kolb, T E; Skelly, J M; Steiner, K C; Joyce, B J; Savage, J E

    1996-05-01

    Foliar ozone uptake rates of different-sized black cherry (Prunus serotina Ehrh.) trees were compared within a deciduous forest and adjacent openings in north-central Pennsylvania during one growing season. Study trees included open-grown seedlings and saplings, forest understory seedlings and saplings, and sunlit and shaded portions of mature canopy tree crowns. Instantaneous ozone uptake rates were highest in high-light environments primarily because of higher stomatal conductances. Low ozone uptake rates of seedlings and saplings in the forest understory could be attributed partially to lower average ambient ozone concentrations compared to the canopy and open environments. Among the tree size and light combinations tested, ozone uptake rates were highest in open-grown seedlings and lowest in forest-grown seedlings. Despite lower ozone uptake rates of foliage in shaded environments, ozone uptake per net photosynthesis of foliage in shaded environments was significantly higher than that of foliage in sunlit environments because of weaker coupling between net photosynthesis and stomatal conductance in shaded environments. The potential for greater ozone injury in shaded environments as a result of greater ozone uptake per net photosynthesis is consistent with previous reports of greater ozone injury in shaded foliage than in sunlit foliage. PMID:14871717

  3. Varietal screening of ozone sensitivity in Mediterranean durum wheat (Triticum durum, Desf.)

    Science.gov (United States)

    Monga, Robert; Marzuoli, Riccardo; Alonso, Rocìo; Bermejo, Victoria; González-Fernández, Ignacio; Faoro, Franco; Gerosa, Giacomo

    2015-06-01

    This study investigated the ozone (O3) sensitivity of five cultivars of durum wheat (Triticum durum) grown in Open-Top Chambers (OTC) during the 2013 growing season. Two levels of ozone were applied during daylight hours: +50% and -50% of ambient ozone concentration respectively in O3-enriched OTC and charcoal-filtered OTC. Results suggest that the significant differences observed in agronomic parameters, were more cultivar-dependent rather than ozone-dependent. Two cultivars showed a significant reduction of aboveground biomass due to ozone (-19.7% and -25%), however only one of them showed also a significant reduction in grain yield (-16%). Stomatal conductance was significantly reduced by ozone fumigation up to -33% in the afternoon measuring cycle. No significant effects on chlorophyll fluorescence were found, nor correlation was observed between ozone-like symptoms severity (leaf chlorotic/necrotic spots) and yield reduction, suggesting that these parameters cannot be indicative of ozone sensitivity/tolerance. These results may be useful for the selection of durum wheat genotypes more adapted for the cultivation in geographical areas where tropospheric ozone is particularly high, but also for the future definition of consistent dose-response relationships to be used in the ozone risk assessment evaluation for the Mediterranean countries.

  4. Atmospheric emissions and economic growth. Environmental Kuznets Curve and Kyoto protocol; Emisiones atmosfericas y crecimiento economico en Espana. La Curve de Kuznets ambiental y el protocolo de Kyoto

    Energy Technology Data Exchange (ETDEWEB)

    Roca Jusmet, J.; Padilla Rosa, E.

    2004-07-01

    From the beginning of the 90s the analysis of the relationships between economic growth and environmental pressures has been influenced by the Environmental Kuznets Curve hypothesis or inverted-U shaped relationship between environmental pressure and per capita income. Following this hypothesis, once achieved certain income level, more economic growth is followed by environmental quality improvement. In this paper, we analyse and discuss the theories that support this hypothesis as well as the empirical evidence on this subject. Further on we analyse the relationship between per capita income and the main environmental pollutants for the case does not support the hypothesis. The empirical evidence shows that economic growth, by itself, does not entail a pollution reduction. (Author) 35 refs.

  5. DEVELOPMENTS IN OZONATION OF WATERS

    OpenAIRE

    Ensar OĞUZ; 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 ...

  6. OZONE ABSORPTION IN RAW WATERS

    OpenAIRE

    LJILJANA TAKI?; VLADA VELJKOVI?; SRDJAN PEJANOVI?

    2008-01-01

    The ozone absorption in raw water entering the main ozonization step at the Belgrade drinking water supply plant was investigated in a continuous stirred tank reactor (CSTR). A slow chemical reaction rate of dissolved ozone and pollutants present in raw water have been experimentally determined. The modified Hatta number was defined and calculated as a criterion which determines whether and to which extent the reactions of ozone and pollutants influence the rate of the pure physical ozone abs...

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

    Science.gov (United States)

    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 the plant surface should be considered as oxygenated VOC source, impacting gas phase chemistry, as well as efficient ozone sink improving the plant's ozone tolerance

  8. The ozone; L'ozone

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-06-01

    In this booklet, the ministry of the national development and environment presents the emergency actions decided by the authorities, in the case of ozone pollution. These measure concern the road traffic. Recommendations are also proposed for the public. (A.L.B.)

  9. Artificial ozone holes

    CERN Document Server

    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.

  10. Estonian total ozone climatology

    OpenAIRE

    Eerme, K.; Veismann, U.; Koppel, R.

    2002-01-01

    The climatological characteristics of total ozone over Estonia based on the Total Ozone Mapping Spectrometer (TOMS) data are discussed. The mean annual cycle during 1979–2000 for the site at 58.3° N and 26.5° E is compiled. The available ground-level data interpolated before TOMS, have been used for trend detection. During the last two decades, the quasi-biennial oscillation (QBO) corrected systematic decrease of total ozone from February–April was 3 ± 2.6% per decade. Before 1980, a s...

  11. Dynamical modes associated with the Antarctic ozone hole

    Directory of Open Access Journals (Sweden)

    B. C. Weare

    2009-02-01

    Full Text Available Generalized Maximum Covariance Analysis (GMCA has been developed and applied to diagnosing the dynamical modes associated with variations in the Antarctic spring ozone hole. GMCA is used to identify the most important patterns of co-variability between interannual ozone mixing ratio variations in the Antarctic region and temperature, zonal, meridional and vertical velocities between 100 and 10 hPa in the same region. The most important two pairs of GMCA time coefficients show large year-to-year variations and trends, which are connected with the growth of the Antarctic Ozone Hole and the increase of ozone depleting substances. The associated spatial patterns of ozone variations may be characterized as being quasi-symmetric and asymmetric about the pole. These patterns of ozone variations are associated with comparable patterns of variations of temperature and winds through most of the vertical domain.

    The year 2000 is shown to be dominated by the asymmetric mode, whereas the adjacent year 2001 is dominated by the quasi-symmetric mode. A case study, focusing on the asymmetric differences between these two years, shows the magnitude of the ozone mixing ratio, temperature and zonal wind differences to be in the range of 2 e-6, 10°C and 10 m/s, respectively. Budget calculations show that transport processes contribute substantially to the ozone and temperature changes in the middle stratosphere over the Antarctic continent. However, both radiative and chemical processes also play important roles in the changes.

  12. Dynamical modes associated with the Antarctic ozone hole

    Directory of Open Access Journals (Sweden)

    B. C. Weare

    2009-08-01

    Full Text Available Generalized Maximum Covariance Analysis (GMCA has been developed and applied to diagnosing the dynamical modes associated with variations in the Antarctic spring ozone hole. GMCA is used to identify the most important patterns of co-variability between interannual ozone mixing ratio variations in the Antarctic region and temperature, zonal, meridional and vertical velocities between 100 and 10 hPa in the same region. The most important two pairs of GMCA time coefficients show large year-to-year variations and trends, which are connected with the growth of the Antarctic Ozone Hole and the increase of ozone depleting substances. The associated spatial patterns of ozone variations may be characterized as being quasi-symmetric and asymmetric about the pole. These patterns of ozone variations are associated with comparable patterns of variations of temperature and winds through most of the vertical domain.

    The year 2000 is shown to be dominated by the asymmetric mode, whereas the adjacent year 2001 is dominated by the quasi-symmetric mode. A case study, focusing on the asymmetric differences between these two years, shows the magnitude of the ozone mixing ratio, temperature and zonal wind differences to be in the range of 2 e–6 kg/kg, 10°C and 10 m/s, respectively. Budget calculations show that transport processes contribute substantially to the ozone and temperature changes in the middle stratosphere over the Antarctic continent. However, both radiative and chemical processes also play important roles in the changes.

  13. Dynamical modes associated with the Antarctic ozone hole

    Science.gov (United States)

    Weare, B. C.

    2009-08-01

    Generalized Maximum Covariance Analysis (GMCA) has been developed and applied to diagnosing the dynamical modes associated with variations in the Antarctic spring ozone hole. GMCA is used to identify the most important patterns of co-variability between interannual ozone mixing ratio variations in the Antarctic region and temperature, zonal, meridional and vertical velocities between 100 and 10 hPa in the same region. The most important two pairs of GMCA time coefficients show large year-to-year variations and trends, which are connected with the growth of the Antarctic Ozone Hole and the increase of ozone depleting substances. The associated spatial patterns of ozone variations may be characterized as being quasi-symmetric and asymmetric about the pole. These patterns of ozone variations are associated with comparable patterns of variations of temperature and winds through most of the vertical domain. The year 2000 is shown to be dominated by the asymmetric mode, whereas the adjacent year 2001 is dominated by the quasi-symmetric mode. A case study, focusing on the asymmetric differences between these two years, shows the magnitude of the ozone mixing ratio, temperature and zonal wind differences to be in the range of 2 e-6 kg/kg, 10°C and 10 m/s, respectively. Budget calculations show that transport processes contribute substantially to the ozone and temperature changes in the middle stratosphere over the Antarctic continent. However, both radiative and chemical processes also play important roles in the changes.

  14. On the Size of the Antarctic Ozone Hole

    Science.gov (United States)

    Newman, Paul A.; Nash, Eric R.; Kawa, S. Randolph

    2002-01-01

    The Antarctic ozone hole is a region of extremely large ozone depletion that is roughly centered over the South Pole. Since 1979, the area coverage of the ozone hole has grown from near zero size to over 24 Million sq km. In the 8-year period from 1981 to 1989, the area expanded by 18 Million sq km. During the last 5 years, the hole has been observed to exceed 25 Million sq km over brief periods. In the spring of 2002, the size of the ozone hole barely reached 20 Million sq km for only a couple of days. We will review these size observations, the size trends, and the interannual variability of the size. The area is derived from the area enclosed by the 220 DU total ozone contour. We will discuss the rationale for the choice of 220 DU: 1) it is located near the steep gradient between southern mid-latitudes and the polar region, and 2) 220 DU is a value that is lower than the pre-1979 ozone observations over Antarctica during the spring period. The phenomenal growth of the ozone hole was directly caused by the increases of chlorine and bromine compounds in the stratosphere. In this talk, we will show the relationship of the ozone hole's size to the interannual variability of Antarctic spring temperatures. In addition, we will show the relationship of these same temperatures to planetary-scale wave forcings.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Teale California Ambient Air Quality Standards for Ozone

    Data.gov (United States)

    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...

  17. 75 FR 2938 - National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-01-19

    ...Virginia--February 2, 2010 Hyatt Regency Crystal City @ Reagan National Airport, Washington Room (located on the...545-562. Olszyk, D., Bytnerowlez, A., Kats, G., Reagan, C., Hake, S., Kerby, T., Millhouse,...

  18. 75 FR 2938 - National Ambient Air Quality Standards for Ozone

    Science.gov (United States)

    2010-01-19

    ... that revision is needed to provide increased public health protection'' (73 FR 16472). The.... Nature of Effects 3. Interpretation and Integration of Health Evidence 4. O 3 -Related Impacts on Public... requisite protection of public health and welfare, respectively. With regard to the primary standard for O...

  19. 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

    Scientific Electronic Library Online (English)

    Eduardo P, Pérez; Carlos, Azócar; Andrea, Araya; Orlando, Astudillo; Marcel, Ramos.

    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 e [...] n 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. Abstract in english 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 (winter) and 2006 (summer). Statistical analysis showed that there are significant statistical differences between cohorts obtained from natural environment and those obtained in hatchery. The Tukey's test showed differences between CN2003 and CH2003 and also between CN2005 and CH2005, while there were no significant differences between CN2006 and CH2006. These differences indicate that the cohorts of natural environment seeds grew faster than those of hatchery. Inter annual comparison showed significant statistical differences. These results are discussed in terms of the cultivation temperature and the heterozygosity for the growing population.

  20. 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

    Directory of Open Access Journals (Sweden)

    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 (winter and 2006 (summer. Statistical analysis showed that there are significant statistical differences between cohorts obtained from natural environment and those obtained in hatchery. The Tukey's test showed differences between CN2003 and CH2003 and also between CN2005 and CH2005, while there were no significant differences between CN2006 and CH2006. These differences indicate that the cohorts of natural environment seeds grew faster than those of hatchery. Inter annual comparison showed significant statistical differences. These results are discussed in terms of the cultivation temperature and the heterozygosity for the growing population.

  1. Changes in growth and 14CO2 fixation of Hordeum vulgare and Phaseolus vulgaris induced by UV-B radiation

    International Nuclear Information System (INIS)

    Increased UV-B radiation on the earth's surface due to depletion of stratospheric ozone layer is one of the changes of current climate-change pattern. A field experiment was concluded to study the effects of solar ultraviolet-B (UV-B) radiation on growth parameters, photosynthetic efficiency (14CO2-fixation) and biochemical characteristics of barley (Hordeum vulgare) and common bean (Phaseolus vulgaris). Plants grown under ambient UV-B radiation were compared with those grown without UV-B by excluding ambient UV-B radiation. To exclude solar ambient UV-B radiation, the sunlight was filtered through a polyester film that selectively absorbed UV-B. For ambient UV-B effects, plants were grown under polyvinyl chloride (PVC) filters that transmitted the complete light spectrum. The results indicated increased shoot length, leaf area, dry matter accumulation, leaf area ratio and specific leaf weight in plants of both the crops grown without UV-B compared with those grown under ambient UV-B. Similarly, the rate of photosynthetic activity, chlorophyll content, nitrates reductase (NR) enzyme activity and sugar content. The effect of UV-B exclusion was clearer in common bean compared with that in barley. We conclude that monocot species may be less sensitive to increased solar UV-B due to ozone depletion than with dicots

  2. 2001 Ozone Design Value

    Data.gov (United States)

    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...

  3. Catalytic for Ozone Converters

    International Science & Technology Center (ISTC)

    Development of New Catalytic Systems, Methods of Formation of Catalytic Elements on this Basis, and Development of a Laboratory Version of the Low-Temperature Catalytic Ozone Converter for Life Support Systems in Civil Aviation

  4. Ozone health effects

    International Nuclear Information System (INIS)

    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

  5. Photochemical processes and ozone production in Finnish conditions

    Energy Technology Data Exchange (ETDEWEB)

    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

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

    International Nuclear Information System (INIS)

    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 ?g m-3 during summer months. However, the zone dominated by residential colonies, offices, and cultivated land showed maximum O3 concentrations less than 60 ?g m-3. Higher concentrations of ozone were mainly recorded in warmer months between 11 am to 4 pm. The highest concentration of 160 ?g 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

  7. Effect of ozone on respiratory responses in subjects with asthma

    Energy Technology Data Exchange (ETDEWEB)

    Koenig, J.Q. [Univ. of Washington, Seattle, WA (United States)

    1995-03-01

    In the process of understanding the respiratory effects of individual air pollutants, it is useful to consider which populations seem to be most susceptible to the exposures. Ozone is the most ubiquitous air pollutant in the United States, and there is great interest in the extent of susceptibility to this air pollutant. This review presents evidence that individuals with asthma are more susceptible to adverse respiratory effects from ozone exposure than are nonasthmatic individuals under similar circumstances. In studies comparing patients with asthma to nonasthmatic subjects, research has shown increased pulmonary-function decrements, an increased frequency of bronchial hyperresponsiveness in ozone responders, increased signs of upper airway inflammation after ozone exposure, and an increased response to inhaled sulfur dioxide or allergen in the subjects with asthma. Subjects with asthma are indeed a population susceptible to the inhaled effects of ozone. These data need to be considered by regulators who are charged with setting air quality standards to protect even the most susceptible members of the population. They also underline the importance of strategies to reduce human exposure to ambient ozone. 16 refs., 1 fig.

  8. High-latitude ozone loss outside the Antarctic ozone hole

    International Nuclear Information System (INIS)

    Data taken during the 1987 Antarctic Airborne Ozone Experiment based in Punta Arenas, Chile, are used to show that from mid-August until the end of the mission in late September there was a high latitude ozone loss outside the Antarctic ozone hole. Therefore, not only is the geographic extent of the ozone loss larger than that generally identified as chemically perturbed, but ozone is lost earlier in the year than previously reported. These results, when compared with long-term temporal trends of column ozone, indicate a possible anthropogenic component for this loss. 30 refs., 4 figs

  9. Ozone: The secret greenhouse gas; Ozon: den hemmelige drivhusgassen

    Energy Technology Data Exchange (ETDEWEB)

    Berntsen, Terje; Tjernshaugen, Andreas

    2001-07-01

    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.

  10. Atmosphere and Ambient Space

    DEFF Research Database (Denmark)

    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...

  11. Stratospheric ozone depletion

    OpenAIRE

    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...

  12. DMAH ozone measurement net

    OpenAIRE

    D. Pagès

    2006-01-01

    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...

  13. Ozone therapy in periodontics

    OpenAIRE

    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...

  14. Crescimento de Aegla platensis Schmitt em ambiente natural (Crustacea, Decapoda, Aeglidae The growth of Aegla platensis Schmitt (Crustacea, Decapoda, Aeglidae in natural habitat

    Directory of Open Access Journals (Sweden)

    Alessandra Angélica de Pádua Bueno

    2000-03-01

    Full Text Available The crustaceans of the genus Aegla Leach, 1820 are found in streams, rivers and lakes from Franca, São Paulo, Brazil (20º60'S, 47º40'W, to Ilha Madre de Dios, Chile (50º01'10"S, 75º18'45"W in South America. The growth and cheliped asymmetry of Aegla platensis Schmitt, 1942 were analyzed. The animals were collected from July 1997 to September 1998 at Arroio do Mineiro, Taquara, Rio Grande do Sul, Brazil (29º46'S, 50º53"W. The sex, length, width of the carapace and the total weight of the crab were registered. And after that, the animals were returned to the stream. In the statistical analysis von Bertalanffy's model was used. The growth curves in length (mm of males and females are described, respectively, by the following equations: L1 = 17.39 [1 - e -0041(t + 3913] and L1 = 19.12 [1 - e -0.0033 (t + 50.38]. The equations that describe the growth in weight (g of males and females, respectively, are: Wt = 2.48 [1 - e -0.0041(t + 3913]3.04 and Wt - 3.38 [1 - e - 0033(t + 50.38]3.05 Among 36,5% males had larger left chelae and 52% of females had chelae of the same size.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Study on ozone treatment of soil for agricultural application of surface dielectric barrier discharge

    Science.gov (United States)

    Nagatomo, Takuya; Abiru, Tomoya; Mitsugi, Fumiaki; Ebihara, Kenji; Nagahama, Kazuhiro

    2016-01-01

    Recently, application of plasma technologies to the agricultural field has attracted much interest because residual pesticides and excessive nitrogen oxides contained in plants, soil, and groundwater have become a serious issue worldwide. Since almost all of the atmospheric discharge plasma generates ozone, the effects of ozone are among the key factors for their agricultural applications. We have proposed the use of ozone generated using surface barrier discharge plasma for soil disinfection or sterilization. In this work, the ozone consumption coefficient and diffusion coefficient in soil were measured by the ultraviolet absorption method. The pH(H2O) and amount of nitrogen nutrient in soil after ozone diffusion treatment were studied and plant growth was observed simultaneously. The effect of ozone treatment on the amount of DNA in soil was also investigated and compared with that determined from the obtained ozone consumption coefficient.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  18. Ozone depletion calculations

    International Nuclear Information System (INIS)

    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

  19. The ozone backlash

    International Nuclear Information System (INIS)

    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

  20. Plant ozone injury symptoms

    Energy Technology Data Exchange (ETDEWEB)

    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.

  1. Det ambientes fænomenologi

    DEFF Research Database (Denmark)

    Walther-Hansen, Mads

    2014-01-01

    Det ambiente: sansning, medialisering, omgivelse er et aktuelt og ambitiøst værk. Bogen skildrer hvordan ambiente fænomener har fået en stigende betydning i den moderne verden, og redegør for måden hvorpå det ambiente virker ind på hele vores oplevelseskultur. Det er en levende, uprætentiøs og fr...

  2. Exposure to moderate concentrations of tropospheric ozone impairs tree stomatal response to carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Onandia, Gabriela [Department of Plant and Environmental Sciences, University of Gothenburg, P. O. Box 461, SE-405 30 Goeteborg (Sweden); Cavanilles Institute of Biodiversity and Evolutionary Biology, Department of Microbiology and Ecology, University of Valencia, E-46100 Burjassot, Valencia (Spain); Olsson, Anna-Karin; Barth, Sabine [Department of Plant and Environmental Sciences, University of Gothenburg, P. O. Box 461, SE-405 30 Goeteborg (Sweden); King, John S. [Department of Forestry and Environmental Resources, Campus Box 8002, North Carolina State University, Raleigh, NC 27695 (United States); Uddling, Johan, E-mail: johan.uddling@dpes.gu.se [Department of Plant and Environmental Sciences, University of Gothenburg, P. O. Box 461, SE-405 30 Goeteborg (Sweden)

    2011-10-15

    With rising concentrations of both atmospheric carbon dioxide (CO{sub 2}) and tropospheric ozone (O{sub 3}), it is important to better understand the interacting effects of these two trace gases on plant physiology affecting land-atmosphere gas exchange. We investigated the effect of growth under elevated CO{sub 2} and O{sub 3}, singly and in combination, on the primary short-term stomatal response to CO{sub 2} concentration in paper birch at the Aspen FACE experiment. Leaves from trees grown in elevated CO{sub 2} and/or O{sub 3} exhibited weaker short-term responses of stomatal conductance to both an increase and a decrease in CO{sub 2} concentration from current ambient level. The impairement of the stomatal CO{sub 2} response by O{sub 3} most likely developed progressively over the growing season as assessed by sap flux measurements. Our results suggest that expectations of plant water-savings and reduced stomatal air pollution uptake under rising atmospheric CO{sub 2} may not hold for northern hardwood forests under concurrently rising tropospheric O{sub 3}. - Exposure to moderate concentrations of tropospheric ozone impairs stomatal CO{sub 2} responsiveness of birch in the Aspen FACE experiment.

  3. The effect of ozone on pollen development in Lolium perenne L

    International Nuclear Information System (INIS)

    Perennial ryegrass plants (Lolium perenne L.) were exposed in 'Closed-Top Chambers' to different ozone concentrations and to charcoal filtered ambient air to study the effect of ozone on the development of pollen. Ozone at ambient (65 nl l-1, 8 h) and elevated (110 nl l-1, 4 h) concentrations affected the maturing of pollen by inhibiting starch accumulation in pollen throughout the anther. Affected pollen persisted in the vacuolated state while normal pollen in the same anther were filled with amyloplasts. The percentage of underdeveloped pollen--determined in transversal sections--was significantly higher in exposed plants than in plants grown in filtered air. Results indicate that ozone stress was responsible for the disrupted development of pollen in L. perenne

  4. The effect of ozone on pollen development in Lolium perenne L

    Energy Technology Data Exchange (ETDEWEB)

    Schoene, K.; Franz, J.-Th.; Masuch, G

    2004-10-01

    Perennial ryegrass plants (Lolium perenne L.) were exposed in 'Closed-Top Chambers' to different ozone concentrations and to charcoal filtered ambient air to study the effect of ozone on the development of pollen. Ozone at ambient (65 nl l{sup -1}, 8 h) and elevated (110 nl l{sup -1}, 4 h) concentrations affected the maturing of pollen by inhibiting starch accumulation in pollen throughout the anther. Affected pollen persisted in the vacuolated state while normal pollen in the same anther were filled with amyloplasts. The percentage of underdeveloped pollen--determined in transversal sections--was significantly higher in exposed plants than in plants grown in filtered air. Results indicate that ozone stress was responsible for the disrupted development of pollen in L. perenne.

  5. Ozone: The secret greenhouse gas

    International Nuclear Information System (INIS)

    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

  6. Efeito da densidade de estocagem na homogeneidade do crescimento de juvenis de pirarucu em ambiente confinado Stocking density effect on growth homogeneity of juvenile pirarucu in confined environments

    Directory of Open Access Journals (Sweden)

    Bruno Adan Sagratzki Cavero

    2003-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o efeito da densidade de estocagem sobre a homogeneidade do crescimento de juvenis de pirarucu (Arapaima gigas em tanques-rede de pequeno volume. Foram usados 12 tanques-rede de 1 m³ em um viveiro de 120 m² perfazendo três tratamentos (15, 20 e 25 peixes/m³ com quatro repetições. Os peixes foram estocados com peso médio inicial de 10,1±0,3 g e distribuídos homogeneamente (p>0,05 entre os tratamentos. Os coeficientes de variação do crescimento e do fator de condição não apresentaram diferenças significativas (p>0,05 ao contrário do consumo e da conversão alimentar aparente (pThe objective of this work was to evaluate the stocking density over fish growth homogeneity of pirarucu (Arapaima gigas juveniles in small volumes cages. Twelve 1 m³ netcages were used in a 120 m² earth pond consisting of three treatments (15, 20 and 25 fish/m³ with four repetitions each. Fish were stocked with an initial mean weight of 10.1±0.3 g and homogeneous distributed (p>0.05 between treatments. Coefficient of variation for growth and condition factor did not present significant (p>0.05 differences, contrary to consumption and apparent feed conversion (p<0.05. Consumption was inversely proportional to the increment of density, indicating that stockings densities increases are favorable to a better feed use. There were not any observed behavior differences between treatments. Juveniles pirarucu growth was not influenced by the stocking density or intraspecifics interactions.

  7. Crecimiento de plántulas de estátice (Limonium sinuatum) y viola (Viola cornuta) en ambientes contrastantes / Growth of statice (Limonium sinuatum) and viola (Viola cornuta) seedlings in contrasting environments

    Scientific Electronic Library Online (English)

    Oscar Javier, Ayala-Garay; José Alfredo, Carrillo-Salazar; Evelia, Hernández-García; Elizabeth, Díaz-Martínez; Manuel, Livera-Muñoz; Gustavo, Almaguer-Vargas.

    2011-08-01

    Full Text Available En producción rústica de ornamentales se requiere conocer el efecto medioambiental en la emergencia y crecimiento de plántulas para optimizar el proceso de producción. El objetivo de esta investigación fue estudiar el efecto de tres condiciones de producción: un túnel cubierto por polietileno, malla [...] -sombra de 50 % de transmisión de radiación solar y a la intemperie, en el crecimiento de plántulas de estátice y viola, durante el invierno en el Valle de México. Se midieron la temperatura del aire, porcentaje de emergencia (E%), área foliar por planta (AF) y biomasa seca por planta (PS) a los 10,18, 24, 31 y 35 días después de siembra (dds) en estátice, y 21, 28, 35, 43 y 52 dds en viola; se calcularon las tasas absoluta de crecimiento (TAC), relativa de crecimiento (TRC) y de asimilación neta (TAN). En túnel de polietileno y malla-sombra se tuvieron valores de E % más altos: 95 y 93 % para estátice y 97 y 95 % para viola, respectivamente. En ambas especies existieron dos cinéticas sigmoidales de crecimiento en PS: la cinética de crecimiento en el túnel de polietileno fue la mayor (P Abstract in english In order to grow ornamental plants in non-controlled environments, the effect of temperature on seedling emergence and growth must be known in order to optimize plant production. The aim of this research was to compare the growth of statice and viola seedlings, during the winter in the Valley of Mex [...] ico, under three production conditions: a polyethylene-covered tunnel, shade netting that cuts light transmission by 50 %, and in the open. We measured air temperature (0C), emergence percentage (E%), leaf area (LA) per plant and dry weight biomass (DWB) per plant at 10, 18, 24, 31 and 35 days after planting (dap) in statice seedlings, and at 21, 28, 35, 43 and 52 dap in viola seedlings. In addition, the absolute growth rate (AGR), the relative growth rate (RGR) and the net assimilation rate (NAR) were calculated. Compared to the outdoor treatment (control), The polyethylene tunnel and shade netting produced higher E% values: 95 and 93 % for statice and 97 and 95 % for viola, respectively. Two different sigmoid curves of dry matter accumulation were observed in both species. The polythene tunnel produced higher DWB than the other conditions (P

  8. 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

    Directory of Open Access Journals (Sweden)

    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 used as a substratum. The following characteristics were evaluated, relative growth rate (RGR, net assimilation rate (NAR, plant height, diameter, dry matter production of the aerial part (DMPAP and amount of nutrient in the dry matter of leaves. We concluded from the results that: low availability of N, Ca and Mg constraints the growth of the Aniba rosaeodora plants. Seedlings of A. rosaeodora required little P, K and S. The omission of Ca and N harmed the RGR of the species. The most important elements for DMPAP were Ca and Mg; the Mg acting more in the leaf area; on the other hand, the omission of sulfur favored the macronutrient absorption (N, P, K, Ca, Mg.

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

    Science.gov (United States)

    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 ozone layer here. The mechanism of the impact of the greenhouse gases on the polar ozone by means of modification of sulphate aerosol distribution in the atmosphere has been revealed and investigated, too. Numerical experiments show that enhancement of the surface area density of sulphate aerosol in the stratosphere caused by the growth of the greenhouse gases will reduce significantly the ozone depletion during the Antarctic ozone hole.

  10. Low soil temperature reduces the positive effects of high nutrient supply on the growth and biomass of white birch seedlings in ambient and elevated carbon dioxide concentrations

    International Nuclear Information System (INIS)

    Global atmospheric carbon dioxide (CO2) concentrations are increasing at a rate of 1.9 ?mol per mol per year as a result of both natural and human-induced emissions. This study investigated the effects of soil temperature and nutrient supply on the growth responses of white birch in relation to increased atmospheric CO2 concentrations. Birch seedlings were grown under 2 different CO2 regimes and 3 different nutrient and soil regimes for a period of 4 months. The study showed that there were significant 3-factor interactive effects on root collar diameter (RCD); stem biomass; and leaf mass ratio. Lower soil temperatures reduced RCD at high nutrient supply ratios. Stem biomass was also reduced at intermediate and high nutrient supply regimes with elevated CO2 ratios. The effect of soil temperature was negligible in low nutrient supply regimes. It was concluded that growth and biomass was higher with higher nutrient supplies at all soil temperatures. Results of the study suggested that low soil temperatures reduced the positive effect of high nutrient supply on biomass production. 68 refs., 1 tab., 3 figs

  11. A Ten-Year Investigation on Ozone and It Precursors at Kemaman, Terengganu, Malaysia

    OpenAIRE

    Marzuki Ismail; Samsuri Abdullah; Fong Si Yuen; Nurul Adyani Ghazali

    2016-01-01

    10 years of continuous monitoring data (2000-2010) from Air Quality Division, Malaysian Department of Environment are used to investigate the relationships between ambient levels of ozone (O3), nitric oxide (NO) and nitrogen dioxide (NO2) as a function of NOx, in Kemaman, Malaysia, wherewith the dominant sources of ozone precursors are industrial activities and road traffic. In addition, variation of oxidant OX (O3 and NO2) concentration with NOx was also examined. The analyses established a ...

  12. Ozone risk for crops and pastures in present and future climates

    Science.gov (United States)

    Fuhrer, Jürg

    2009-02-01

    Ozone is the most important regional-scale air pollutant causing risks for vegetation and human health in many parts of the world. Ozone impacts on yield and quality of crops and pastures depend on precursor emissions, atmospheric transport and leaf uptake and on the plant’s biochemical defence capacity, all of which are influenced by changing climatic conditions, increasing atmospheric CO2 and altered emission patterns. In this article, recent findings about ozone effects under current conditions and trends in regional ozone levels and in climatic factors affecting the plant’s sensitivity to ozone are reviewed in order to assess implications of these developments for future regional ozone risks. Based on pessimistic IPCC emission scenarios for many cropland regions elevated mean ozone levels in surface air are projected for 2050 and beyond as a result of both increasing emissions and positive effects of climate change on ozone formation and higher cumulative ozone exposure during an extended growing season resulting from increasing length and frequency of ozone episodes. At the same time, crop sensitivity may decline in areas where warming is accompanied by drying, such as southern and central Europe, in contrast to areas at higher latitudes where rapid warming is projected to occur in the absence of declining air and soil moisture. In regions with rapid industrialisation and population growth and with little regulatory action, ozone risks are projected to increase most dramatically, thus causing negative impacts major staple crops such as rice and wheat and, consequently, on food security. Crop improvement may be a way to increase crop cross-tolerance to co-occurring stresses from heat, drought and ozone. However, the review reveals that besides uncertainties in climate projections, parameters in models for ozone risk assessment are also uncertain and model improvements are necessary to better define specific targets for crop improvements, to identify regions most at risk from ozone in a future climate and to set robust effect-based ozone standards.

  13. Ozone decreases soybean productivity and water use efficiency

    Science.gov (United States)

    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...

  14. Ozonation of Canadian Athabasca asphaltene

    Science.gov (United States)

    Cha, Zhixiong

    Application of ozonation in the petrochemical industry for heavy hydrocarbon upgrading has not been sufficiently explored. Among heavy hydrocarbons, asphaltenes are the heaviest and the most difficult fractions for analysis and treatment. Therefore, ozonation of asphaltenes presents an interesting application in the petrochemical industry. Commercial application of ozonation in the petrochemical industry has three obstacles: availability of an ozone-resistant and environmentally friendly solvent, the precipitation of ozonation intermediates during reaction, and recovery of the solvent and separation of the ozonation products. Preliminary ozonation of Athabasca oil sands asphaltene in nonparticipating solvents encountered serious precipitation of the ozonation intermediates. The precipitated intermediates could be polymeric ozonides and intermolecular ozonides or polymeric peroxides. Because the inhomogeneous reaction medium caused low ozone efficiency, various participating solvents such as methanol and acetic acid were added to form more soluble hydroperoxides. The mass balance results showed that on average, one asphaltene molecule reacted with 12 ozone molecules through the electrophilic reaction and the subsequent decomposition of ozonation intermediates generated acetone extractable products. GC/MS analysis of these compounds indicated that the free radical reactions could be important for generation of volatile products. The extensively ozonated asphaltene in the presence of participating solvents were refluxed with methanol to generate more volatile products. GC/MS analysis of the methanol-esterified ozonation products indicated that most volatile products were aliphatic carboxylic acid esters generated through cleavage of substituents. Reaction kinetics study showed that asphaltene ozonation was initially a diffusion rate-controlled reaction and later developed to a chemical reaction rate-controlled reaction after depletion of the reactive aromatic sites. Two new solvent systems, a self-sustaining ozonation system and a cyclohexane/acetone/water or a cyclohexane/acetone/methanol system, were studied to overcome the drawback of using halogenated solvents. The self-sustaining ozonation process employed the final ozonation products as the reaction solvent. Compared to the self-sustaining ozonation, the cyclohexane solvent system showed higher ozone efficiency; however, it required dynamic adjustment of the solvent system during ozonation. An extensively ozonated asphaltene's weight would be doubled. Distillation of the products separated about 45% volatile products having biodiesel-style chemical structures. Compared to distillation, more than 90% of the ozonation products were extractable by acetone. The remaining acetone-insoluble part was further classified by dichloromethane and other solvents of different polarities. The separated ozonation products were good fuel additives or materials for other products.

  15. Ozone modeling within plasmas for ozone sensor applications

    OpenAIRE

    Arshak, Khalil; Forde, Edward; Guiney, Ivor

    2007-01-01

    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. Rate constant...

  16. Have ozone effects on carbon sequestration been overestimated?: a new biomass response function for wheat

    OpenAIRE

    H. Pleijel; Danielsson, H.(Institut für Physik, Universität Mainz, D-55099 Mainz, Germany 11 11 Funded by the German Federal Minister for Education and Research (BMBF) under contract 05HA6UMA .); Simpson, D.; Mills, G.

    2014-01-01

    Elevated levels of tropospheric ozone can significantly impair the growth of crops. The reduced removal of CO2 by plants leads to higher atmospheric concentrations of CO2, enhancing radiative forcing. Ozone effects on economic yield, e.g. the grain yield of wheat (Triticum aestivum L.), are currently used to model effects on radiative forcing. However, changes in grain yield do not necessarily reflect changes in total biomass. Based on an analysis of 22 ozone exposure experi...

  17. CONTRIBUTION TO INDOOR OZONE LEVELS OF AN OZONE GENERATOR

    Science.gov (United States)

    This report gives results of a study of a commonly used commercially available ozone generator, undertaken to determine its impact on indoor ozone levels. xperiment were conducted in a typical mechanically ventilated office and in a test house. he generated ozone and the in-room ...

  18. Ambient air pollution and low birthweight

    DEFF Research Database (Denmark)

    Pedersen, Marie; Giorgis-Allemand, Lise; Bernard, Claire; Aguilera, Inmaculada; Andersen, Anne-Marie Nybo; Ballester, Ferran; Beelen, Rob M J; Chatzi, Leda; Cirach, Marta; Danileviciute, Asta; Dedele, Audrius; Eijsden, Manon van; Estarlich, Marisa; Fernández-Somoano, Ana; Fernández, Mariana F; Forastiere, Francesco; Gehring, Ulrike; Grazuleviciene, Regina; Gruzieva, Olena; Heude, Barbara; Hoek, Gerard; de Hoogh, Kees; van den Hooven, Edith H; Håberg, Siri E; Jaddoe, Vincent W V; Klümper, Claudia; Korek, Michal; Krämer, Ursula; Lerchundi, Aitana; Lepeule, Johanna; Nafstad, Per; Nystad, Wenche; Patelarou, Evridiki; Porta, Daniela; Postma, Dirkje; Raaschou-Nielsen, Ole; Rudnai, Peter; Sunyer, Jordi; Stephanou, Euripides; Sørensen, Mette; Thiering, Elisabeth; Tuffnell, Derek; Varró, Mihály J; Vrijkotte, Tanja G M; Wijga, Alet; Wilhelm, Michael; Wright, John; Nieuwenhuijsen, Mark J; Pershagen, Göran; Brunekreef, Bert; Kogevinas, Manolis; Slama, Rémy

    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-based mother-child cohort studies in 12 European countries. Overall, the study population included 74?178 women who had singleton deliveries between Feb 11, 1994, and June 2, 2011, and for whom informatio...

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

    International Nuclear Information System (INIS)

    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)

  20. Revealing source signatures in ambient BTEX concentrations

    International Nuclear Information System (INIS)

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

    Science.gov (United States)

    Davis, Donald D; Orendovici, Teodora

    2006-10-01

    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. PMID:16458398

  2. "OZONE SOURCE APPORTIONMENT IN CMAQ'

    Science.gov (United States)

    Ozone source attribution has been used to support various policy purposes including interstate transport (Cross State Air Pollution Rule) by U.S. EPA and ozone nonattainment area designations by State agencies. Common scientific applications include tracking intercontinental tran...

  3. Ozone-depleting Substances (ODS)

    Data.gov (United States)

    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...

  4. Ozone production at NSLS

    International Nuclear Information System (INIS)

    Ozone production by synchrotron radiation as a function of power density in air was investigated using a white beam at the BNL National Synchrotron Light Source (NSLS) x-ray ring. Power densities were calculated from the energy spectrum at 2.52 GeV. Ozone concentrations in small beam pipes were measured for power densities between I = 10/sup 12/ and 10/sup 15/ eV/sup . /cm/sup -3 . /sec/sup -1/. The measured ozone half-life was 37+-2 min. The measured G-value was 2.69+-0.14 mol/100 eV and the ozone destruction factor k was less than 5 x 10/sup -19/cm/sup 3//eV. The random uncertainties stated are approximately one standard error. The large departure of the values for G and k from previous values suggest that some undiscovered systematic error may exist in the experiment. Ozone concentration in excess of the 0.1 ppm ACGIH TLV can be generated in the experimental hutches but can readily be controlled. Industrial hygiene aspects of operation and possible control measures are discussed

  5. 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

    Science.gov (United States)

    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 < 0.001), serum glutathione (GSH) content (day 14, P = 0.02; day 28, P = 0.045), glutathione peroxidase (GSH-Px) activity, and total antioxidant capacity (T-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 %.

  6. Extrapolating future Arctic ozone losses

    OpenAIRE

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

    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 is that Arctic ozone...

  7. What Controls the Size of the Antarctic Ozone Hole?

    Science.gov (United States)

    Bhartia, P. K. (Technical Monitor); Newman, Paul A.; Kawa, S. Randolph; Nash, Eric R.

    2002-01-01

    The Antarctic ozone hole is a region of extremely large ozone depletion that is roughly centered over the South Pole. Since 1979, the area coverage of the ozone hole has grown from near zero size to over 24 Million square kilometers. In the 8-year period from 1981 to 1989, the area expanded by 18 Million square kilometers. During the last 5 years, the hole has been observed to exceed 25 Million square kilometers over brief periods. We will review these size observations, the size trends, and the interannual variability of the size. The area is derived from the area enclosed by the 220 DU total ozone contour. We will discuss the rationale for the choice of 220 DU: 1) it is located near the steep gradient between southern mid-latitudes and the polar region, and 2) 220 DU is a value that is lower than the pre- 1979 ozone observations over Antarctica during the spring period. The phenomenal growth of the ozone hole was directly caused by the increases of chlorine and bromine compounds in the stratosphere. In this talk, we will show the relationship of the ozone hole's size to the interannual variability of Antarctic spring temperatures. In addition, we will show the relationship of these same temperatures to planetary-scale wave forcings.

  8. Expected short-term local effect of nuclear bombs on stratospheric ozone

    International Nuclear Information System (INIS)

    Nuclear bomb tests in the atmosphere produce both oxides of nitrogen and ozone. For bomb yields of 1 Ml or more, much of the bomb-produced radioactivity, ozone, and NO/sub x/ are lifted into the stratosphere. Bomb-produced NO/sub x/ constitutes a prompt one-time source of ozone if NO2 is in excess of NO relative to the ambient NO2/NO ratio, and it constitutes a fast (minutes) one-time destruction of ozone if NO is in excess. At a considerably slower, elevation-dependent rate the bomb-produced NO/sub x/ is expected catalytically to destroy some stratospheric ozone. A 2-Ml nuclear bomb, exploded near 15degreeS on July 4, 1970, stabilized between 15 and 20 km with maximum concentration of radioactivity at 18 km. Christie (1976) deduced the trajectory and size of this nuclear bomb cloud for 10 days and examined the detailed record of total ozone observed at that time by the Nimbus 4 satellite. The present article carries out calculations for several chemical processes expected to occur in this nuclear bomb cloud. There is a wide range of uncertainty as to how much NO/sub x/ and ozone the nuclear bomb injected into the stratosphere. The central expectation value, referred to 18 km, is that bomb-produced ozone would increase local stratospheric ozone by 40% on the first day: upon expansion of the cloud the increase drops to 2% by the eighth day; and it would require 2 months for the bomb-produced NO/sub x/ to destroy the bomb-produced ozone. There would be very little NO/sub x/ catalytic destruction of stratospheric ozone from this nuclear bomb during its first 10 days; it did not rise high enough into the stratosphere to cause a fast destruction of ozone. The observations by Christie are in agreement with current models of nuclear bombs and stratospheric photochemistry

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

    International Nuclear Information System (INIS)

    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

  10. Slow Crack Growth Behavior and Life/Reliability Analysis of 96 wt % Alumina at Ambient Temperature With Various Specimen/Loading Configurations

    Science.gov (United States)

    Choi, Sung R.; Powers, Lynn M.; Nemeth, Noel N.

    2000-01-01

    Extensive constant stress-rate testing for 96 wt % alumina was conducted in room-temperature distilled water using four different specimen/loading configurations: rectangular beam test specimens under four-point uniaxial flexure, square plate test specimens in ring-on-ring biaxial flexure, square plate test specimens in ball-on-ring biaxial flexure, and dog-boned tensile test specimens in pure tension. The slow crack growth (SCG) parameter n was almost independent of specimen/loading configurations, in either four-point uniaxial flexure, ring-on-ring biaxial flexure, ball-on-ring biaxial flexure, or pure tension, ranging from n = 35 to 47 with an average value of n = 41.1 +/- 4.5. The prediction of fatigue strength/reliability based on the four-point uniaxial flexure data by using the CARES/Life design code as well as a simple PIA model was in good agreement with both the ring-on-ring biaxial and the ball-on-ring biaxial flexure data. A poor prediction using the PIA model was observed for the dog-boned tensile test specimens, presumably due to different flaw population involved in the tensile test specimens.

  11. Ozone removal by HVAC filters

    Science.gov (United States)

    Zhao, P.; Siegel, J. A.; Corsi, R. L.

    Residential and commercial HVAC filters that have been loaded with particles during operation in the field can remove ozone from intake or recirculated air. However, knowledge of the relative importance of HVAC filters as a removal mechanism for ozone in residential and commercial buildings is incomplete. We measured the ozone removal efficiencies of clean (unused) fiberglass, clean synthetic filters, and field-loaded residential and commercial filters in a controlled laboratory setting. For most filters, the ozone removal efficiency declined rapidly but converged to a non-zero (steady-state) value. This steady-state ozone removal efficiency varied from 0% to 9% for clean filters. The mean steady-state ozone removal efficiencies for loaded residential and commercial filters were 10% and 41%, respectively. Repeated exposure of filters to ozone following a 24-h period of no exposure led to a regeneration of ozone removal efficiency. Based on a theoretical scaling analysis of mechanisms that are involved in the ozone removal process, we speculate that the steady-state ozone removal efficiency is limited by reactant diffusion out of particles, and that regeneration is due to internal diffusion of reactive species to sites available to ozone for reaction. Finally, by applying our results to a screening model for typical residential and commercial buildings, HVAC filters were estimated to contribute 22% and 95%, respectively, of total ozone removal in HVAC systems.

  12. Ozonated Olive Oils and Troubles

    Directory of Open Access Journals (Sweden)

    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

  13. Ozone: Genesis, effects, hazards; Ozon: Entstehung, Wirkung, Risiken

    Energy Technology Data Exchange (ETDEWEB)

    Sandermann, H.

    2001-07-01

    An international expert explains the structure and function of ozone, the anthropogenic changes in ozone concentrations and the ozone increase in the summer season as well as the main aspects of 'summer smog' and 'ozone depletion'. [German] In diesem Buch erlaeutert ein international anerkannter Experte Aufbau und natuerliche Funktionen des Ozons, er beschreibt sein veraendertes Auftreten in unserer natuerlichen Umwelt sowie das Zustandekommen von Grenzwerten, und er erklaert die wichtigsten Aspekte von ''Sommersmog'' und ''Ozonloch''. (orig.)

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

    OpenAIRE

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

    2014-01-01

    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 from the Los Angeles Basi...

  15. Modifiers of Short-term Effects of Ozone on Mortality in Eastern Massachusetts: A Case-crossover Analysis at Individual Level

    OpenAIRE

    Schwartz Joel; Melly Steve; Ren Cizao

    2010-01-01

    Abstract Background Substantial epidemiological studies demonstrate associations between exposure to ambient ozone and mortality. A few studies simply examine the modification of this ozone effect by individual characteristics and socioeconomic status, but socioeconomic status was usually coded at the city level. Methods This study used a case-crossover design to examine whether impacts of ozone on mortality were modified by socioeconomic status coded at the tract or characteristics at an ind...

  16. Ozone Therapy in Dentistry

    Directory of Open Access Journals (Sweden)

    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

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

    OpenAIRE

    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 ...

  18. Tropospheric ozone in the vicinity of the ozone hole - 1987 Airborne Antarctic Ozone Experiment

    Science.gov (United States)

    Gregory, Gerald L.; Warren, Linda S.; Hypes, Warren D.; Tuck, Adrian F.; Kelly, Kenneth K.; Krueger, Arlin J.

    1989-01-01

    Results are presented on ozone measurements in the upper troposphere/lower stratosphere over Antarctica, obtained by NASA DC-8 aircraft during the August/September 1987 Airborne Antarctic Ozone Experiment. The ozone mixing ratios as high as several hundred ppbv were measured, but in all cases these ratios were observed in pockets of upper atmospheric air, both in the vicinity of and away from the location of the ozone hole. The background ozone values in the surrounding troposphere were typically in the range of 20-50 ppbv. Correlation of tropospheric ozone observations with the boundaries of the ozone hole differed in the course of the experiment. During the August 28 - September 2 flights, encounters with ozone-rich air were limited, and the background tropospheric ozone appeared to decrease beneath the hole. For the later flights, and as the ozone hole deepened, the ozone-rich air was frequently observed in the vicinity of the hole, and the average ozone values at the flight altitude were frequently higher than the background values.

  19. Estimate of initial isoprene contribution to ozone formation potential in Beijing, China

    Science.gov (United States)

    Xie, Xin; Shao, Min; Liu, Ying; Lu, Sihua; Chang, Chih-Chung; Chen, Zhong-Ming

    Volatile organic compounds (VOCs) are important precursors of tropospheric ozone formation. Isoprene contributions to ozone formation by using ambient mixing ratios are generally underestimated because of rapid chemical losses. In this study, ambient mixing ratios of major VOC species were continuously measured at Peking university (PKU) and YUFA, urban and sub-urban sites in Beijing, the city that will host 2008 Olympic Games. The observed mixing ratios of methyl vinyl ketone (MVK), methacrolein (MACR) and isoprene were used to derive the mixing ratios of initial isoprene, which means the ambient isoprene level before it undergoes any photochemical reaction with OH radicals. The average mixing ratios of initial isoprene were 3.3±1.6 and 2.9±1.5 ppbv at PKU and YUFA sites, respectively. The percentages of initial isoprene in total initial VOCs were 10.8% at PKU site and 11.4% at YUFA site, in reasonable agreement with the isoprene contribution in total VOC emissions as derived from source inventories. Maximum increment reactivity (MIR) was used to evaluate the ozone formation potential (OFP) for major VOC species. The OFP for initial isoprene accounted for 23% of the total OFPs for all measured species, compared to 11% using ambient mixing ratios of isoprene at PKU site. Similarly, at YUFA site, the ambient measured isoprene and initial isoprene contributed 10% and 22%, respectively, to the OFPs for total measured VOCs. It seems that isoprene has similar contribution to ozone formation at both sites in Beijing city.

  20. Indicators of Antarctic ozone depletion

    OpenAIRE

    Bodeker, G. E.; H. Shiona; Eskes, H.

    2005-01-01

    An assimilated data base of total column ozone measurements from satellites has been used to generate a set of indicators describing attributes of the Antarctic ozone hole for the period 1979 to 2003, including (i) daily measures of the area over Antarctica where ozone levels are below 150DU, below 220DU, more than 30% below 1979 to 1981 norms, and more than 50% below 1979 to 1981 norms, (ii) the date of disappearance of 150DU ozone values, 220DU ozone values, values 30% below 1979 to 1981 no...

  1. DEVELOPMENTS IN OZONATION OF WATERS

    Directory of Open Access Journals (Sweden)

    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.

  2. Complex interplay of future climate levels of CO2, ozone and temperature on susceptibility to fungal diseases in barley

    DEFF Research Database (Denmark)

    Mikkelsen, Bolette Lind; Bagger JØrgensen, Rikke

    2015-01-01

    Barley (Hordeum vulgare) was grown in different climatic environments with elevated [CO2] (700 vs 385 ppm), [O3] (60/90 vs 20 ppb) and temperature (24/19 vs 19/12°C day/night) as single factors and in combinations, to evaluate the impact of these climatic factors on photosynthesis and susceptibility to powdery mildew and spot blotch disease. No significant increase in net CO2 assimilation rate was observed in barley grown under elevated [CO2] at ambient temperature. However, this rate was positively stimulated under elevated temperature together with a slightly higher potential quantum efficiency of PSII, both at ambient and elevated [CO2], suggesting that photosynthesis was not limited by [CO2] at ambient temperature. When growing under elevated temperature or [O3], infection by the biotrophic powdery mildew fungus decreased, whereas disease symptoms and growth of the toxin-secreting hemibiotrophic spot blotch fungus increased compared to ambient conditions, implying that climate-induced changes in disease severity could be linked to the trophic lifestyle of the pathogens. Elevated [CO2] decreased powdery mildew infection but had no effect on spot blotch disease compared to ambient condition. However, the effect of elevated [CO2], [O3] and temperature did not act in an additive manner when combined. This led to a surprising disease development in the combination treatments, where powdery mildew infection increased despite the individual reducing effect of the climatic factors, and spot blotch disease decreased despite the individual promoting effect of temperature and ozone, emphasizing the importance of conducting multifactorial experiments when evaluating the potential effects of climate change.

  3. 13C/12C ratios as indicators of plant physiological response to ozone and simulated acid rain

    International Nuclear Information System (INIS)

    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

  4. U.S. census unit population exposures to ambient air pollutants

    Directory of Open Access Journals (Sweden)

    Hao Yongping

    2012-01-01

    Full Text Available Abstract Background Progress has been made recently in estimating ambient PM2.5 (particulate matter with aerodynamic diameter 2.5 and ozone for U.S. CGUs. Methods We converted 2001-2006 gridded data, generated by the U.S. Environmental Protection Agency (EPA for CDC's (Centers for Disease Control and Prevention Environmental Public Health Tracking Network (EPHTN, to census block group (BG based on spatial proximities between BG and its four nearest grids. We used a bottom-up (fine to coarse strategy to generate population exposure estimates for larger CGUs by aggregating BG estimates weighted by population distribution. Results The BG daily estimates were comparable to monitoring data. On average, the estimates deviated by 2 ?g/m3 (for PM2.5 and 3 ppb (for ozone from their corresponding observed values. Population exposures to ambient PM2.5 and ozone varied greatly across the U.S. In 2006, estimates for daily potential population exposure to ambient PM2.5 in west coast states, the northwest and a few areas in the east and estimates for daily potential population exposure to ambient ozone in most of California and a few areas in the east/southeast exceeded the National Ambient Air Quality Standards (NAAQS for at least 7 days. Conclusions These estimates may be useful in assessing health impacts through linkage studies and in communicating with the public and policy makers for potential intervention.

  5. Influence of fertilization on the growth of radicchio "Rosso di Chioggia" cultivated in two different environments / Influencia de la fertilización en el crecimiento de radicchio "Rosso di Chioggia" cultivado en dos ambientes diferentes

    Scientific Electronic Library Online (English)

    Maria Flavia, Filippini; Carlo, Nicoletto; Paolo, Sambo; Juan Bruno, Cavagnaro; Ferdinando, Pimpini.

    2011-12-01

    Full Text Available Este trabajo evalúa la influencia de la fertilización en radicchio tipo "Rosso de Chioggia" (precocidad media) sobre algunos índices de crecimiento. Se realizaron ensayos durante dos campañas en Rovigo (Italia) y una en Mendoza (Argentina), aplicándose dosis crecientes de NPK, identificadas como N0P [...] 0K0, N1P1K1, N2P2K2, en Mendoza y en Rovigo, además, N3P2K2. Durante el cultivo se calcularon índices de crecimiento como: relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf area (SLA), leaf weigh ratio (LWR), crop growth ratio (CGR), leaf area index (LAI) and leaf area duration (LAD). En Mendoza, el CGR estuvo fuertemente influenciado por NAR desde el trasplante hasta alcanzar 776 grados días (GDD); desde 1052 a 1653 GDD el CGR fue afectado por el LAI el cual aumentó marcadamente debido a las condiciones ambientales favorables. Entre los 1052 y 1653 GDD el incremento del LAI determinó una reducción en la eficiencia fotosintética. En Rovigo, la tendencia de los índices fue disímil en los dos años, encontrándose respuestas diferentes en LAR y en SLA. En el segundo año, el CGR siempre arrojó valores más altos, mientras que NAR no difirió en ninguno de los años. En la segunda mitad del ciclo, CGR estuvo fuertemente asociado a una menor eficiencia fotosintética, debido a la formación de la cabeza. Valores elevados de LAI indicaron una extensión del ciclo, retrasando la formación de la cabeza. Las plantas alcanzaron la madurez comercial con LWR entre 0,35 - 0,40 g g-1. En ambos ambientes, no se observó claramente el efecto de la fertilización sobre los índices; si bien las dosis más altas mostraron mayor actividad de crecimiento en las etapas tempranas. Abstract in english This study evaluated the influence of fertilization on some growth indexes in radicchio "Rosso di Chioggia". The trial was conducted in Rovigo (Italy) for two years and in Mendoza (Argentina) for one year. Increasing doses of macronutrients were considered, identified as N0P0K0, N1P1K1, N2P2K2 and, [...] only in Rovigo, N3P2K2. Some indexes related to growth analysis: relative growth rate (RGR), net assimilation rate (NAR), leaf area ratio (LAR), specific leaf area (SLA), leaf weigh ratio (LWR), crop growth ratio (CGR), leaf area index (LAI) and leaf area duration (LAD) were calculated during the growing cycle. At Mendoza CGR was strongly influenced by NAR from transplant until 776 growth degree days (GDD). After that moment, CGR was affected by LAI that increased markedly due to favourable environmental conditions. From 1052 to 1653 GDD the high increase of LAI determined a reduction in photosynthetic efficiency. At Rovigo the trends in index values showed differences between the two years considered, especially in LAR and SLA. In the second year CGR had always higher values; mainly due to higher LAI values, since NAR did not differ significantly during the years. In the second half of the growing cycle, CGR was instead strongly linked to a contraction of photosynthetic effectiveness, due to head formation. High LAI values showed a growing cycle extension to the detriment of early head formation. It was also observed that when LWR is around 0.35 - 0.40 g g-1, the plant reaches marketable maturation and is ready to be harvested. In both environments, no clear effects of fertilization were observed on the growth indexes. In any case highly fertilized plants showed higher growing activity especially at the beginning of the growing cycle.

  6. Acerca de la biotecnología ambiental

    Directory of Open Access Journals (Sweden)

    Blasco Pla, Rafael

    2014-08-01

    Full Text Available The aim of environmental biotecnology is to correct environmental imbalances caused by modern industrial activities. Many of these imbalances affect biogeochemical cycles in the biosphere, mainly catalysed by microorganisms. Deviations in the balances of carbon, nitrogen, sulphur and iron compounds may cause very complex phenomena such as global warming, destruction of the ozone layer, environmental pollution and acidification of the sea. On the other hand, the poorly understood microbial interactions --either with each other or the environment-- have important consequences in generating highly recalcitrant chemical species which, accumulating in the trophic chains, are highly toxic for living organisms. To cope with these problems it is necessary to improve knowledge of microbial ecology and the functioning of the biogeochemical cycles at the molecular level, although it is also worth designing technologies to eliminate pollutants either in situ or ex situ, to avoid its uncontrolled production as well as to correct the unbalancing processes affecting phases of the biogeochemical cycles, either in the present day or in the future.La Biotecnología ambiental trata de corregir los desequilibrios causados en el medio ambiente por actividades industriales que alteran los ecosistemas naturales mediante contaminación química o biológica y que también afectan a los grandes ciclos biogeoquímicos en la biosfera, mayoritariamente catalizados por seres vivos, entre los que los microrganismos juegan un papel esencial. Las desviaciones en los balances de compuestos carbonados, nitrogenados y azufrados atmosféricos pueden causar fenómenos de gran complejidad como el calentamiento global, la destrucción de la capa de ozono, la contaminación ambiental o la lluvia ácida. Por otra parte, las interacciones de los microorganismos entre sí y con el medio, desconocidas en su mayor parte, tiene importantes repercusiones en la generación y persistencia de especies químicas que, depositadas en las cadenas tróficas, son altamente tóxicas para los organismos vivos. Para atajar estos problemas es necesario avanzar en el conocimiento a nivel molecular de la ecología microbiana y del funcionamiento de los ciclos biogeoquímicos, aunque no es menos necesario desarrollar tecnologías para la eliminación de contaminantes industriales in situ y ex situ, evitar su producción y utilización incontroladas así como corregir las actuaciones desequilibrantes, actuales o futuras, de la biogeoquímica planetaria.

  7. Uso de subprodutos de carvão vegetal na formação do porta-enxerto limoeiro 'Cravo' em ambiente protegido / The use of byproducts of vegetal charcoal on growth of 'Rangpur' lime rootstock under screen house

    Scientific Electronic Library Online (English)

    Marcelo, Zanetti; Jairo Osvaldo, Cazetta; Dirceu de, Mattos Júnior; Sérgio Alves de, Carvalho.

    2003-12-01

    Full Text Available O trabalho teve como objetivo avaliar o efeito do uso de fino de carvão no substrato e da aplicação de extrato pirolenhoso no substrato e na planta sobre o desenvolvimento de porta-enxertos de limoeiro 'Cravo' (Citrus limonia Osbeck) cultivados em ambiente protegido. O experimento foi desenvolvido n [...] o delineamento em blocos casualisados, com análise em esquema fatorial 3 x 2 x 3, sendo: 3 proporções de fino de carvão (0, 100 e 200 cm³ dm-3) em mistura com substrato comercial, 2 concentrações de extrato pirolenhoso (0 e 20 cm³ dm-3) misturadas no substrato (240 cm³ por dm³ de substrato) e 3 concentrações de extrato pirolenhoso (0, 5 e 10 cm³ dm-3) pulverizadas na parte aérea, em 4 repetições. Aos 150 e 180 dias após o plantio foram realizadas avaliações do desenvolvimento das plantas. As misturas de fino de carvão e substrato comercial contendo fino de carvão na proporção de 100 cm³ dm-3 não influíram no desenvolvimento de porta-enxertos de limoeiro 'Cravo' , porém, na proporção de 200 cm³ dm-3 prejudica o desenvolvimento dos mesmos. O umedecimento pré-plantio do substrato com solução diluída (20 cm³ dm-3) de extrato pirolenhoso ou pulverização da parte aérea das plantas com soluções a 5 e 10 cm³ dm-3 provoca redução do desenvolvimento de porta-enxertos de limoeiro 'Cravo' . Abstract in english The effect of finely grounded charcoal and pyroligneous acid (PA) in mixture with a commercial growing media and PA sprayed on leaves on growth of Rangpur lime (Citrus limonia Osbeck) seedlings under screen house was studied. Treatments consisted in a combination of 3 levels of charcoal (0, 100 and [...] 200 cm³ dm-3) mixture on the commercial growing media, 2 rates of PA mixtured (0 and 20 cm³ dm-3) to a growing media (240 cm³ per dm³ of growing media), and 3 rates of PA (0, 5 and 10 cm³ dm-3) sprayed on the leaves, with 4 replications. The experiment was carried out in a randomized complete block design, and analyzed as a factorial 3 x 2 x 3. Growth of seedlings was evaluated at 150 and 180 days after planting. The presence of charcoal at 100 cm³ dm-3 in the media did not influence on growth of seedlings. However, the mixture with 200 cm³ dm-3 of charcoal reduced production of total dry mass and high of the plants. The addition of PA (solution 20 cm³ dm-3) to the media reduced plant growth, and sprayed (solutions 5 and 10 cm³ dm-3) on the leaves reduced seedlings diameter.

  8. Outdoor and indoor ozone level: A potential impact on human health

    Directory of Open Access Journals (Sweden)

    Valuntait? Vaida

    2015-01-01

    Full Text Available Background/Aim. Air pollution outside and inside is still one of the most sensitive issues. The aim of this study was to assess the ozone level in ambient air and working premises in terms of its possible influence on human health. Methods. The study was based on the results obtained in Lithuanian conditions. Continuous ozone measurement data from the rural monitoring station in Preila over the period 1995-2011 were analyzed. More than 180,000 hourly values were examined according to the requirements in the Directive 2008/50/EC. The World Health Organization (WHO and European Union indicators the Sum of Ozone Means Over 35 ppb (SOMO 35, the maximum daily 8-hour mean concentration of ozone higher than 100 and 120 ?g/m3 were estimated. Indoor ozone concentrations in copying and welding rooms were evaluated. The ozone concentration was measured with the ozone analyzer O341M. Results. The frequency distribution of ozone hourly concentrations at the Preila station showed that less than 1% of the data were higher than 120 ?g/m3 and 6% of them higher than 100 ?g/m3, that could have the adverse effect on human health, during 1995-2011. The investigations made in working premises showed that near a copying machine the ozone concentration can reach 330 ?g/m3, however in the room, i.e. 0.5 m from the machine, the average ozone concentration during automatic copying was 165 ?g/m³ and during manual copying it was 50 ?g/m³. Measurements in a welding room showed that the ozone concentration was in the range of 380-1,850 ?g/m3 at the distance of 25 cm from the electrode and at the distance of 1 m from the source the ozone concentration decreased 2.5 times. Conclusion. The danger of the ambient ozone level to human health practically was not observed in Lithuanian conditions. However, almost 6% of the data exceed the new WHO guideline of 100 ?g/m3 during the measurement time. Indoor ozone during welding reached a higher level than during copying that can cause human health problems.

  9. GEMS stratospheric ozone evaluation

    Science.gov (United States)

    Lefever, K.; Daerden, F.; Chabrillat, S.; Flentje, H.; Stein, O.; Moinat, P.; Huijnen, V.; Flemming, J.; Schulz, M.; Gems Grg Team

    2009-04-01

    The EU FP6 Integrated Project "Global Earth-system (atmosphere) Monitoring using Satellite and in-situ data" (GEMS, http://gems.ecmwf.int/) aims at developing the world's first operational chemical weather system, providing daily analyzes and forecasts for trace atmospheric constituents which are important for climate, air quality and UV radiation. It concerns simulations from the lower troposphere up to the stratosphere, on the global as well as on the regional scale. The present poster presents the evaluation of stratospheric ozone simulations in the GEMS system during the chosen test year 2003. 4D stratospheric ozone fields produced by several development phases of the GEMS system will be assessed. These comprise the standalone CTMs driven by offline meteorological data, forecasts by the coupled GEMS GRG system for global reactive gases and the GEMS GRG reanalyzes, resulting from the assimilation of ozone from SCIAMACHY, MIPAS, GOME and SBUV. To evaluate the performance of each individual run, we compare the ozone fields with both an independent assimilation system (BASCOE) and independent satellite data (TOMS, POAM and HALOE). We present the standardized evaluation routines we developed to this end and the methods we applied to optimally assess the differences between the chemical models and the observational data.

  10. Revisiting Antarctic Ozone Depletion

    Science.gov (United States)

    Grooß, Jens-Uwe; Tritscher, Ines; Müller, Rolf

    2015-04-01

    Antarctic ozone depletion is known for almost three decades and it has been well settled that it is caused by chlorine catalysed ozone depletion inside the polar vortex. However, there are still some details, which need to be clarified. In particular, there is a current debate on the relative importance of liquid aerosol and crystalline NAT and ice particles for chlorine activation. Particles have a threefold impact on polar chlorine chemistry, temporary removal of HNO3 from the gas-phase (uptake), permanent removal of HNO3 from the atmosphere (denitrification), and chlorine activation through heterogeneous reactions. We have performed simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) employing a recently developed algorithm for saturation-dependent NAT nucleation for the Antarctic winters 2011 and 2012. The simulation results are compared with different satellite observations. With the help of these simulations, we investigate the role of the different processes responsible for chlorine activation and ozone depletion. Especially the sensitivity with respect to the particle type has been investigated. If temperatures are artificially forced to only allow cold binary liquid aerosol, the simulation still shows significant chlorine activation and ozone depletion. The results of the 3-D Chemical Transport Model CLaMS simulations differ from purely Lagrangian longtime trajectory box model simulations which indicates the importance of mixing processes.

  11. Ozone decomposing filter

    Science.gov (United States)

    Simandl, Ronald F. (Farragut, TN); Brown, John D. (Harriman, TN); Whinnery, Jr., LeRoy L. (Dublin, CA)

    1999-01-01

    In an improved ozone decomposing air filter carbon fibers are held together with a carbonized binder in a perforated structure. The structure is made by combining rayon fibers with gelatin, forming the mixture in a mold, freeze-drying, and vacuum baking.

  12. Ozone in stratosphere

    International Nuclear Information System (INIS)

    The menace of supersonic aircraft and bomb aerosol against the ozone layer that shields earth from most of the sun cancer-providing ultraviolet rays is examined. Large research programs are developed in view of answering the question, but the models proposed still yield controversial data

  13. Ozone, greenhouse effect

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Principal Component Analysis of Chlorophyll Content in Tobacco, Bean and Petunia Plants Exposed to Different Tropospheric Ozone Concentrations

    Science.gov (United States)

    Borowiak, Klaudia; Zbierska, Janina; Budka, Anna; Kayzer, Dariusz

    2014-06-01

    Three plant species were assessed in this study - ozone-sensitive and -resistant tobacco, ozone-sensitive petunia and bean. Plants were exposed to ambient air conditions for several weeks in two sites differing in tropospheric ozone concentrations in the growing season of 2009. Every week chlorophyll contents were analysed. Cumulative ozone effects on the chlorophyll content in relation to other meteorological parameters were evaluated using principal component analysis, while the relation between certain days of measurements of the plants were analysed using multivariate analysis of variance. Results revealed variability between plant species response. However, some similarities were noted. Positive relations of all chlorophyll forms to cumulative ozone concentration (AOT 40) were found for all the plant species that were examined. The chlorophyll b/a ratio revealed an opposite position to ozone concentration only in the ozone-resistant tobacco cultivar. In all the plant species the highest average chlorophyll content was noted after the 7th day of the experiment. Afterwards, the plants usually revealed various responses. Ozone-sensitive tobacco revealed decrease of chlorophyll content, and after few weeks of decline again an increase was observed. Probably, due to the accommodation for the stress factor. While during first three weeks relatively high levels of chlorophyll contents were noted in ozone-resistant tobacco. Petunia revealed a slow decrease of chlorophyll content and the lowest values at the end of the experiment. A comparison between the plant species revealed the highest level of chlorophyll contents in ozone-resistant tobacco.

  17. Principal Component Analysis of Chlorophyll Content in Tobacco, Bean and Petunia Plants Exposed to Different Tropospheric Ozone Concentrations

    Directory of Open Access Journals (Sweden)

    Borowiak Klaudia

    2014-06-01

    Full Text Available Three plant species were assessed in this study - ozone-sensitive and -resistant tobacco, ozone-sensitive petunia and bean. Plants were exposed to ambient air conditions for several weeks in two sites differing in tropospheric ozone concentrations in the growing season of 2009. Every week chlorophyll contents were analysed. Cumulative ozone effects on the chlorophyll content in relation to other meteorological parameters were evaluated using principal component analysis, while the relation between certain days of measurements of the plants were analysed using multivariate analysis of variance. Results revealed variability between plant species response. However, some similarities were noted. Positive relations of all chlorophyll forms to cumulative ozone concentration (AOT 40 were found for all the plant species that were examined. The chlorophyll b/a ratio revealed an opposite position to ozone concentration only in the ozone-resistant tobacco cultivar. In all the plant species the highest average chlorophyll content was noted after the 7th day of the experiment. Afterwards, the plants usually revealed various responses. Ozone-sensitive tobacco revealed decrease of chlorophyll content, and after few weeks of decline again an increase was observed. Probably, due to the accommodation for the stress factor. While during first three weeks relatively high levels of chlorophyll contents were noted in ozone-resistant tobacco. Petunia revealed a slow decrease of chlorophyll content and the lowest values at the end of the experiment. A comparison between the plant species revealed the highest level of chlorophyll contents in ozone-resistant tobacco.

  18. Ozone Bioindicator Gardens: an Educational Tool to Raise Awareness about Environmental Pollution and its Effects on Living Systems

    Science.gov (United States)

    Lapina, K.; Lombardozzi, D.

    2014-12-01

    High concentrations of ground-level ozone cause health problems in humans and a number of negative effects on plants, from reduced yield for major agricultural crops to reduced amounts of carbon stored in trees. The Denver Metro/Colorado Front Range is exceeding the National Ambient Air Quality Standard for ozone on a regular basis in summer and the efforts to reduce the ozone levels are hampered by the presence of diverse pollution sources and complex meteorology in the region. To raise public awareness of air quality in the Colorado Front Range and to educate all age groups about ground-level ozone, two ozone bioindicator gardens were planted in Boulder in Spring 2014. The gardens contain ozone-sensitive plants that develop a characteristic ozone injury when exposed to high levels of ozone. The ozone gardens are providing the general public with a real-life demonstration of the negative effects of ozone pollution through observable plant damage. Additionally, the gardens are useful in teaching students how to collect and analyze real-world scientific data.

  19. Licenciamento ambiental e sustentabilidade

    Directory of Open Access Journals (Sweden)

    Marcelo Macedo Valinhas

    2011-12-01

    Full Text Available A sustentabilidade está apoiada principalmente nas dimensões econômica, ambiental e social. No entanto, sem a dimensão política ela não se constrói. Um dos principais instrumentos de comando e controle da política nacional de meio ambiente, o licenciamento ambiental é um processo contínuo de gestão ambiental pública e privada. Analisou-se o processo de licenciamento ambiental como acoplamento estrutural entre os sistemas social, econômico e ambiental. Apesar da constatação de críticas aos mecanismos de comando e controle dos últimos anos, foi verificado que o Estado do Rio de Janeiro tem buscado integrar a política ambiental do Estado à gestão ambiental privada e que esta integração busca atender às demandas dos sistemas sociais e econômicos para as questões ambientais. Em linhas gerais, este caminho segue as estratégias e ações propostas na Agenda 21 brasileira.

  20. Ozone stress and antioxidant substances in Trifolium repens and Centaurea jacea leaves

    International Nuclear Information System (INIS)

    Ozone-sensitive (NC-S clone) and resistant plants (NC-R clone) of Trifolium repens and Centaurea jacea were exposed to moderate ozone concentrations in ambient air. The aim of this study was the investigation of the relation between ozone-sensitivity and leaf concentrations of antioxidants (ascorbic acid, total phenolics and total antioxidant capacity). NC-R clone showed the highest concentrations of antioxidants with 50-70% more ascorbic acid than NC-S. NC-R had about 5 times more ascorbic acid in the young leaves and 9 times more in the old leaves than Centaurea. In a fumigation experiment with acute ozone stress (100 nl L-1) the antioxidant levels changed profoundly. The ozone-injured leaves of NC-S had 6-8 times more total phenolics than uninjured leaves. Generally older leaves had lower antioxidant concentrations and were more prone to ozone injury than younger leaves. Ascorbic acid concentrations were closer related to the appearance of visible ozone injury than the other antioxidative parameters. - Low leaf ascorbic acid levels are a main cause for visible ozone injuries in Trifolium and Centaurea

  1. Ozone stress and antioxidant substances in Trifolium repens and Centaurea jacea leaves

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira Severino, Joyce [Department of Environmental Research/UU, ARC Seibersdorf Research GmbH, A-2444 Seibersdorf (Austria) and Vienna University of Technology, Institute of Chemical Engineering, Getreidemark 9/166, 1060 Vienna (Austria)]. E-mail: y.ferreira-severino@umweltforschung.at; Stich, Karl [Vienna University of Technology, Institute of Chemical Engineering, Getreidemark 9/166, 1060 Vienna (Austria); Soja, Gerhard [Department of Environmental Research/UU, ARC Seibersdorf Research GmbH, A-2444 Seibersdorf (Austria)]. E-mail: gerhard.soja@arcs.ac.at

    2007-04-15

    Ozone-sensitive (NC-S clone) and resistant plants (NC-R clone) of Trifolium repens and Centaurea jacea were exposed to moderate ozone concentrations in ambient air. The aim of this study was the investigation of the relation between ozone-sensitivity and leaf concentrations of antioxidants (ascorbic acid, total phenolics and total antioxidant capacity). NC-R clone showed the highest concentrations of antioxidants with 50-70% more ascorbic acid than NC-S. NC-R had about 5 times more ascorbic acid in the young leaves and 9 times more in the old leaves than Centaurea. In a fumigation experiment with acute ozone stress (100 nl L{sup -1}) the antioxidant levels changed profoundly. The ozone-injured leaves of NC-S had 6-8 times more total phenolics than uninjured leaves. Generally older leaves had lower antioxidant concentrations and were more prone to ozone injury than younger leaves. Ascorbic acid concentrations were closer related to the appearance of visible ozone injury than the other antioxidative parameters. - Low leaf ascorbic acid levels are a main cause for visible ozone injuries in Trifolium and Centaurea.

  2. Response of native plants of northeastern United States and southern Spain to ozone exposures; determining exposure/response relationships

    International Nuclear Information System (INIS)

    Numerous plants species confirmed sensitive to ambient ozone in eastern United States, and southeastern Spain. - Tropospheric ozone has been identified as the most important regional scale air pollutant across much of eastern United States of America and many areas of Mediterranean climes in southern Europe. Recent field surveys in the northeastern USA and in southeastern Spain have revealed many additional plant species that exhibit symptoms typical of ozone-induced injuries. Objectives of this study were to confirm ozone as the cause of the observed foliar symptoms, determine ozone induced exposure/response relationships, and identify possible bio-indicator species. Thirteen native species of northeastern USA and 27 native species of southeastern Spain were selected for study. Plant species were exposed to ozone within 16 CSTR chambers in a greenhouse during the summer seasons of 2000 and 2001; ozone exposures of 30, 60, 90, and 120 ppb were delivered for 7 h/day, 5 days/week. Results have confirmed that with few exceptions, symptoms observed in the field were induced by exposures to ambient ozone. Species differed significantly in terms of the exposures required for the initiation of visible symptoms and subsequent injury progression

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

    OpenAIRE

    P. C. Chen; 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...

  4. Non-Thermal Plasma Ozone Generation

    OpenAIRE

    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.

  5. Non-Thermal Plasma Ozone Generation

    Directory of Open Access Journals (Sweden)

    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.

  6. Tropospheric ozone in the vicinity of the ozone hole: 1987 Airborne Antarctic Ozone Experiment

    International Nuclear Information System (INIS)

    Tropospheric ozone measurements over Antarctica aboard the NASA DC-8 aircraft are summarized. As part of the August/September 1987 Airborne Antarctic Ozone Experiment, the aircraft flew 13 missions covering a latitude of 53 degree-90 degree S, at altitudes to 13 km. Ozone mixing ratios as high as several hundred parts per billion by volume (ppbv) were measured, but in all cases these ratios were observed in pockets or patches of upper atmospheric air. These pockets were observed both in the vicinity of and away from the location of the ozone hole. At times, and as a result of these pockets, the ozone levels at the flight altitude of the aircraft, as averaged beneath the boundaries of the stratospheric ozone hole, were 2-3 times higher than background tropospheric values. The data suggest that the ozone-rich air seldom penetrated below about 9-km altitude. Background ozone values in the surrounding troposphere were typically in the range of 20-50 ppbv. Correlation of tropospheric ozone observations with the boundaries of the ozone hole differed during the experiment. During the early flights (August 28 through September 2), encounters with ozone-rich air were limited and background tropospheric ozone (at the flight altitude) appeared to decrease beneath the hole. For many of the later flights, and as the hole deepened, the reverse was noted, in that ozone-rich air was frequently observed in the vicinity of the hole and, as noted earlier, average ozone at the flight altitude was frequently higher than background values

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

    International Nuclear Information System (INIS)

    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.

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

    Directory of Open Access Journals (Sweden)

    W. L. Lin

    2012-04-01

    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 volatile organic compounds (VOCs. Ozone pollution was found to be more severe in Tianjin than in Shanghai during the summer, either based on the frequency or the duration of high ozone events. Such differences might be attributed to the large amount of highly reactive VOC mixture in the Tianjin region. It is found that industry related species like light alkenes were of particular importance in both urban and suburban Tianjin, while in Shanghai aromatics dominate. 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 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. Ozone production in summer in the megacities of Tianjin and Shanghai, China: a comparative study

    Directory of Open Access Journals (Sweden)

    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.

  10. Some effects of ozonation of humic substances in drinking water

    Science.gov (United States)

    Hongve, Dag; Lund, Vidar; Åkesson, Gunvor; Becher, Georg

    Ozonation is employed as a method for removal of colour due to humic substances in drinking water. We have examined some effects of ozonation of humic water in the laboratory. Ozonation reduced colour by 80% but had little influence on the DOC concentration and only moderate effect on the UV absorbance at 254 nm. High-performance size-exclusion chromatography (HPSEC) showed that the content of high-molecular-weight substances was reduced while a nearly corresponding amount of low-molecular-weight compounds was produced. The produced substances have acidic properties, are uncoloured and do not absorb UV light at 254 nm. Ozonation also led to higher BOD values. The formed low-molecular-weight compounds were consumed by microorganisms. In the original humic water sample the microbial degradation affected only high-molecular-weight compounds. The higher content of biodegradable organic compounds in ozonated drinking water is probably responsible for accelerated growth of bacteria and production of sludge in the distribution systems of a Norwegian waterwork. The obtained colour reduction seems to be temporary, since the colour of ozonated water increases under the influence of microorganisms.

  11. Efecto de dos ambientes lumínicos en el crecimiento inicial y calidad de plantas de Crescentia cujete Effect of two light environments on the initial growth and quality of Crescentia cujete

    Directory of Open Access Journals (Sweden)

    Margarito Piña

    2010-04-01

    Full Text Available Crescentia cujete (Bignoniaceae es una especie nativa de porte pequeño, raíces profundas y arquitectura, flores y frutos ornamentales que la hacen adecuada para la arborización urbana, además de sus usos en la medicina tradicional y elaboración de artesanía. La planta se adapta bien a condiciones semi-áridas. El objetivo de este trabajo fue evaluar el efecto de dos ambientes lumínicos (luz y sombra en el crecimiento inicial y calidad de la planta. La intensidad promedio máxima en horas del día fue de 1170 µmol·m-2·s-1 en el tratamiento de luz, y de 280 µmol·m-2·s-1 en el tratamiento de sombra. Las plántulas con dos pares de hojas verdaderas se colocaron en recipientes y se llevaron a los dos ambientes de luminosidad. A los seis meses, las plantas bajo sombra fueron más altas y con menor diámetro de tallo, con hojas más grandes y mayor contenido de clorofila. La acumulación total de biomasa seca no difirió entre tratamientos, pero la distribución de fotoasimilados fue mayor hacia el componente foliar en las condiciones de sombra y hacia las raíces en la mayor intensidad lumínica. La relación biomasa foliar/biomasa radical bajo sombra duplicó el promedio obtenido en el tratamiento de luz. Aunque en ambos ambientes lumínicos los parámetros de calidad de planta expresados en los índices de esbeltez y calidad de Dickson fueron aceptables, las plantas que crecieron a 1170 µmol· m-2·s-1 fueron de mayor calidad. La especie desarrolló plasticidad morfológica y fisiológica que le permitió adaptarse a las iradiancias evaluadas.Crescentia cujete is a small, deep rooted native plant whose architecture, flowers and ornamental fruit makes it suitable for urban tree, in addition to its use in traditional medicine and handicrafts. The plant is well adapted to semi-arid conditions The objective of this study was to evaluate the effect of two light environments (light and shade on the initial growth and quality of C. cujete plants. The mean maximum ligth intensity at midday was 1170 µmol·m-2·s-1 in the lighted treatment and 280 µmol·m-2·s-1 under the shade. Seedlings with two pairs of true leaves were transplanted into containers and placed under the two environments. Six months later, shade plants were taller and with less stem diameter, with larger leaves and higher chlorophyll content. Total accumulation of biomass did not differ between treatments, but the assimilated distribution was higher toward the leaf component under shade conditions and higher toward the roots under the lighted treatment. The leaf to root biomass ratio under shade doubled the average obtained under light. Although in both environments the quality indexes were acceptable, the plants that grew at 1170 µmol. m-2.s-1 showed higher quality. This species developed morphological and physiological plasticity that allowed it to adapt to both light environments.

  12. Evaluation of the ORYZA2000 Rice Growth Model under Nitrogen-Limited Conditions in an Irrigated Mediterranean Environment Evaluación del Modelo de Crecimiento de Arroz ORYZA2000 bajo Condiciones Limitadas de Nitrógeno en un Ambiente Mediterráneo Regado

    Directory of Open Access Journals (Sweden)

    Pamela Artacho

    2011-03-01

    Full Text Available ORYZA2000 is a growth model for tropical lowland rice ( Oryza sativa L. developed by the International Rice Research Institute and Wageningen University. This model has been evaluated extensively in a wide range of environments. However, reports examining japonica cultivars growing in temperate climates are scarce. In this study, ORYZA2000 was calibrated and evaluated using data from experiments carried out in the South-Central area of Chile. These experiments were performed on a japonica rice cultivar growing under an irrigated Mediterranean environment at various N rates. ORYZA2000 was then applied to explore potential yield and grain yield response to N fertilization under likely weather conditions in the major rice-producing area in Chile. ORYZA2000 was sufficiently accurate to simulate grain yield and crop N uptake at the end of the season. Final crop N uptake was simulated with a root mean squared error (RMSE of 20 kg ha-1 (15% and grain yield with a RMSE of 1666 kg ha-1 (19%. However, the prediction of biomass and N uptake of individual organs throughout the season was poor. A long-term simulation study confirmed a potential yield as high as 12 000 kg ha-1 in the Parral area, as well as the existence of a scope for yield increase. The yield response to N fertilization was predicted even at rates of 300 kg ha-1, although a significant probability of low yields was also observed. This trend supports the need to incorporate dynamic N management in Chilean rice production.ORYZA2000 es un modelo para arroz tropical regado desarrollado por el Instituto Internacional de Investigación en Arroz y Universidad de Wageningen, que ha sido evaluado en un amplio rango de ambientes. Sin embargo, los reportes para cultivares japónica creciendo en ambientes templados son escasos. En este estudio, ORYZA2000 fue calibrado y evaluado usando datos de experimentos realizados en el centro-sur de Chile, que incluyeron una variedad japónica cultivada bajo un ambiente Mediterráneo regado, y varias dosis de N. Posteriormente ORYZA2000 fue aplicado para explorar rendimientos potenciales y respuesta en rendimiento a la fertilización N bajo probables condiciones climáticas de la principal zona arrocera de Chile. ORYZA2000 fue suficientemente preciso en simular rendimiento de grano y absorción de N del cultivo al final de la estación. La absorción de N del cultivo fue simulada con una raíz del cuadrado medio del error (RMSE de 20 kg ha-1 (15% y el rendimiento de grano con una RMSE de 1666 kg ha-1 (19%. La predicción de biomasa y absorción de N de órganos individuales durante la estación fue pobre. El estudio de simulación a largo plazo confirmó un rendimiento potencial tan alto como 12 000 kg ha-1 en Parral, y la existencia de un margen para incrementar los rendimientos. La respuesta en rendimiento a la fertilización N fue predicha aún a dosis de 300 kg ha-1, aunque también se observó una probabilidad significativa de bajos rendimientos. Este hecho apoya la necesidad de incorporar un manejo dinámico del N en la producción arrocera chilena.

  13. Knowledge about stratospheric ozone; Erkenntnisse zum Ozon in der Stratosphaere

    Energy Technology Data Exchange (ETDEWEB)

    Zellner, R. [Essen Univ. (Gesamthochschule) (Germany). Inst. fuer Physikalische und Theoretische Chemie

    2000-12-01

    The contribution outlines the status of stratospheric ozone research. The processes of ozone formation and the main causes and extent of ozone depletion are gone into as well as the atmospherical dynamics and chemistry. Agreements for protection of the ozone layer are mentioned. [German] Der Beitrag gibt einen Ueberblick zum Stand der stratosphaerischen Ozonforschung. Es werden die Prozesse der Ozonbildung sowie die wichtigsten Ursachen und das beobachtete Ausmass des Ozonabbaus beschrieben. Dabei wird sowohl auf die Dynamik wie auf die Atmosphaerenchemie eingegangen. Vereinbarungen zum Schutz der Ozonschicht werden genannt.

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

    International Nuclear Information System (INIS)

    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 (mostly in October). The truck pathway tends to cause a much wider fluctuation in degradation or improvement of ozone air quality: percentage changes in peak ozone concentrations are approximately -0.01% to 0.04% for the assumed 9% market penetration, and approximately -0.03% to 0.1% for the 20% market penetration. Moreover, the 20% on-site pathway occasionally results in a decrease of about -0.1% of baseline ozone pollution. Compared to the current ambient pollution level, all three hydrogen pathways are unlikely to cause a serious ozone problem for market penetration levels of HFCVs in the 9-20% range. (Author)

  15. Development of a portable instrument to measure ozone production rates in the troposphere

    Science.gov (United States)

    Sklaveniti, Sofia; Locoge, Nadine; Stevens, Philip; Kumar, Vinod; Sinha, Vinayak; Dusanter, Sébastien

    2015-04-01

    Ground-level ozone is a key species related to air pollution, causing respiratory problems, damaging crops and forests, and affecting the climate. Our current understanding of the tropospheric ozone-forming chemistry indicates that net ozone production occurs via reactions of peroxy radicals (HO2 + RO2) with NO producing NO2, whose photolysis leads to O3 formation. Production rates of tropospheric ozone, P(O3), depend on concentrations of oxides of nitrogen (NOx = NO + NO2) and Volatile Organic Compounds (V OCs), but also on production rates of ROx radicals (OH + HO2 + RO2). The formation of ozone follows a complex nonlinear chemistry that makes strategies for reducing ozone difficult to implement. In this context, atmospheric chemistry models are used to develop emission regulations, but there are still uncertainties associated with the chemical mechanisms used in these models. Testing the ozone formation chemistry in atmospheric models is needed, in order to ensure the development of effective strategies for ozone reduction. We will present the development of an instrument for direct measurements of ozone production rates (OPR) in ambient air. The OPR instrument is made of three components: (i) two quartz flow tubes to sample ambient air, one exposed to solar radiation and one covered by a UV filter, (ii) a NO2-to-O3 conversion unit, and (iii) an ozone analyzer. The total amount of ozone exiting each flow tube is conserved in the form of Ox = NO2 + O3. Ozone production rates P(O3) are derived from the difference in Ox concentration between the two flow tubes, divided by the exposure time of air inside the flow tubes. We will present studies that were carried out in the laboratory to characterize each part of the instrument and we will discuss the performances of the OPR instrument based on experiments carried out using synthetic air mixtures of known composition (NOx and V OCs). Chemical modeling will also be presented to assess the reliability of ozone production rate measurements.

  16. El ambiente social

    Directory of Open Access Journals (Sweden)

    Henry Granada

    2001-01-01

    Full Text Available Con el título de« Ambiente Social» se quiere enfatizar que el concepto de Ambiente no se agota en lo ecológico (físico-biótico. Así mismo, dentro lo psicosocial, la noción de territorio adquiere importancia y otorga significación a la «experiencia ambiental», ya que abre ventanas hacia la comprensión de actividades como el ordenamiento territorial y a la mediación de las dimensiones psicológica, social y cultural del espacio. Finalmente, aunque el ordenamiento del territorio suele enfocarse desde los componentes sociopolíticos y económicos con el ánimo de planificación, el componente psicosocial traduce aspectos del ordenamiento dentro de la vida cotidiana y relaciona nociones como identidad y arraigo, entre otras.

  17. Inhomogeneous Ambient Metrics

    CERN Document Server

    Graham, C R; Hirachi, Kengo

    2006-01-01

    An extension of the ambient metric construction of Fefferman-Graham to infinite order in even dimensions is described. The main ingredients are the introduction of "inhomogeneous ambient metrics" with asymptotic expansions involving the logarithm of a defining function homogeneous of degree 2, and an invariant procedure for taking the smooth part of such an inhomogeneous ambient metric. The metrics which result depend on the choice of an "ambiguity tensor" as well as a conformal class. An application to the description of scalar conformal invariants in even dimensions is outlined.

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

    International Nuclear Information System (INIS)

    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

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

    International Nuclear Information System (INIS)

    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

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

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Donald D. [Department of Plant Pathology, Ecology Program, Penn State Institutes of the Environment, Pennsylvania State University, University Park, PA 16803 (United States)]. E-mail: ddd2@psu.edu; Orendovici, Teodora [Department of Plant Pathology, Ecology Program, Penn State Institutes of the Environment, Pennsylvania State University, University Park, PA 16803 (United States)

    2006-10-15

    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.

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

    Indian Academy of Sciences (India)

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

    2008-06-01

    The in?uence 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Ozone: Good Up High, Bad Nearby

    Science.gov (United States)

    ... used in coolants, foaming agents, fire extinguishers, solvents, pesticides, and aerosol propellants. Once released into the air ... and other countries stop producing ozone-depleting substances, natural ozone production should return the ozone layer to ...

  4. Indicators of Antarctic ozone depletion

    Directory of Open Access Journals (Sweden)

    G. E. Bodeker

    2005-01-01

    Full Text Available An assimilated data base of total column ozone measurements from satellites has been used to generate a set of indicators describing attributes of the Antarctic ozone hole for the period 1979 to 2003, including (i daily measures of the area over Antarctica where ozone levels are below 150 DU, below 220 DU, more than 30% below 1979 to 1981 norms, and more than 50% below 1979 to 1981 norms, (ii the date of disappearance of 150 DU ozone values, 220 DU ozone values, values 30% below 1979 to 1981 norms, and values 50% below 1979 to 1981 norms, for each year, (iii daily minimum total column ozone values over Antarctica, and (iv daily values of the ozone mass deficit based on a O3<220 DU threshold. The assimilated data base combines satellite-based ozone measurements from 4 Total Ozone Mapping Spectrometer (TOMS instruments, 3 different retrievals from the Global Ozone Monitoring Experiment (GOME, and data from 4 Solar Backscatter Ultra-Violet (SBUV instruments. Comparisons with the global ground-based Dobson spectrophotometer network are used to remove offsets and drifts between the different data sets to produce a global homogeneous data set that combines the advantages of good spatial coverage of satellite data with good long-term stability of ground-based measurements. One potential use of the derived indices is detection of the expected recovery of the Antarctic ozone hole. The suitability of the derived indicators to this task is discussed in the context of their variability and their susceptibility to saturation effects which makes them less responsive to decreasing stratospheric halogen loading. It is also shown that if the corrections required to match recent Earth Probe TOMS measurements to Dobson measurements are not applied, some of the indictors are affected so as to obscure detection of the recovery of the Antarctic ozone hole.

  5. 77 FR 24399 - Approval and Promulgation of Implementation Plans; Georgia; Atlanta; Ozone 2002 Base Year...

    Science.gov (United States)

    2012-04-24

    ... nonattainment designations. Therefore, the Atlanta Area's original attainment date was June 15, 2007. See 69 FR... extension of the attainment date for the 1997 8-hour ozone NAAQS for the Atlanta Area. See 75 FR 73969. As a... FR 23857, April 30, 2004).\\1\\ Ambient air quality monitoring data for the 3-year period must meet...

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

    Science.gov (United States)

    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...

  7. Influência da matéria orgânica e do ambiente no crescimento e acúmulo de solutos em Morinda citrifolia submetida à salinidade / Influence of organic matter and the environment in growth and in solute accumulation in Morinda citrifolia submitted to salinity

    Scientific Electronic Library Online (English)

    Maria Cristina Martins Ribeiro de, Souza; Claudivan Feitosa de, Lacerda; Aiala Vieira, Amorim; Ademir Silva, Menezes.

    2014-09-01

    Full Text Available O Noni (Morinda citrifolia L.) é uma planta tolerante aos efeitos salinos e alcalinos dos solos e desenvolve-se em regiões de clima seco ou úmido. Apesar da adaptabilidade intercontinental, ainda são poucas as informações sobre sua tolerância aos sais no solo brasileiro. Baseado no exposto, objetivo [...] u-se com o presente trabalho avaliar os efeitos da água salina no crescimento inicial do Noni. Para isso, foi conduzido um experimento em vasos de polietileno com capacidade para 20 L, em Sobral, Ceará. O delineamento estatístico adotado foi em blocos ao acaso, disposto no esquema de parcelas subsubdivididas, com 5 repetições. As parcelas foram constituídas pelos ambientes de cultivo (céu aberto e telado), as subparcelas pelos níveis de salinidade da água de irrigação (CEa: 0,3;1,5; 3,0; 4,5 e 6,0 dS m-1) e as subsubparcelas foram representadas pela ausência e presença de matéria orgânica. Aos 110 dias após a aplicação dos tratamentos (DAT), avaliaram-se: altura, massa seca da parte aérea (MSPA), da raiz (MSR), total (MST) e área foliar (AF), e aos 90 (DAT) os teores foliares de solutos orgânicos. Todas as variáveis de crescimento estudadas foram afetadas negativamente pela salinidade, sendo que o efeito observado a céu aberto foi mais expressivo do que no ambiente telado. A matéria orgânica não teve efeito atenuante sobre os efeitos deletérios da salinidade em plantas de noni. O acúmulo de prolina mostrou-se um sinalizador de dano causado pelo estresse, visto que os maiores acúmulos ocorreram nas plantas que sofreram maiores reduções no crescimento. Abstract in english Noni (Morinda citrifolia L.) is a plant tolerant to the effects of saline and alkaline soils and grows in dry or moist climates. Despite the intercontinental adaptability, in Brazil there is little information about its tolerance to soil salinity. The objective of the present study was to evaluate t [...] he effects of saline water on the growth of Noni. For this an experiment was conducted in polyethylene pots with a capacity of 20 L, in Sobral, Ceará. The statistical design was a randomized block design arranged in split plot scheme, with 5 repetitions. The plots consisted of the cultivation environments (open sky and greenhouse), the subplots by salinity levels of irrigation water (ECw: 0.3, 1.5, 3.0, 4.5 and 6.0 dS m-1), and the subsubplots were represented by the absence and presence of organic matter. At 110 days after treatment (DAT), the following variables were evaluated: height, shoot dry mass (SDM), root dry mass (RDM), total dry mass (TDM) and leaf area (LA) and at 90 DAT organic solutes in the leaf. All variables were negatively affected by salinity and the effect observed in the open environment was more intense than under greenhouse conditions. The organic matter had no effect on mitigating the deleterious effects of salinity in plants of noni. The accumulation of proline was found to be a sign of stress damage, since the highest accumulation of this solute was observed in plants that experienced greater reductions in growth.

  8. Residential indoor air quality guideline : ozone

    International Nuclear Information System (INIS)

    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.

  9. El medio ambiente urbano

    OpenAIRE

    Ángel Maya, Augusto; Velásquez Barrero, Luz Stella

    2009-01-01

    En Colombia,  los Grupos  de Estudios Ambientales Urbanos ­GEA­UR­ que integran desde 1992  la  Red  Latinoamericana  de  Estudios  Ambientales  Urbanos,  han  planteado  una  nueva forma  de  interpretar  la  ciudad  desde  la  perspectiva  ambiental,  a  partir  de  estudios  de  caso  que permitieron  construir  propuestas  teóricas  y  metodológicas  para  abordar  la  problemática  y  el potencial  ambiental  de  los  asentamientos  humanos.  En  este  ensayo  puesto  a  consideración  d...

  10. 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

    Energy Technology Data Exchange (ETDEWEB)

    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}.

  11. Influence of minerals supply on the 'acute yellowing' syndrome as well as on growth increment, pigment balance, photosynthesis, frost hardiness, and sensitivity to ozone in Picea abies (L. ) Karst. Einfluss der Mineralstoffversorgung auf das Krankheitsbild 'akute Vergilbung', sowie auf Zuwachs, Pigmenthaushalt, Photosynthese, Frostresistenz und Empfindlichkeit gegenueber Ozon bei Picea abies (L. ) Karst

    Energy Technology Data Exchange (ETDEWEB)

    Hoepker, K.A.

    1989-07-19

    In this work the relevance of soil, soil-water balance (drought, waterlogging), tropospheric factors (air pollutants), and biotic factors (microorganisms) for the triggering of yellowing symptoms, biomass development, photosynthesis, the pigment balance, and frost hardiness in spruce was investigated. For this purpose a planting experiment was carried out where healthy tree-nursery material of different origin was planted in containers containing original soil from a yellowed spruce stand in the Bavarian Forest. Collaterally, the influence of minerals supply on ozone sensitivity in spruce was investigated in an ozone fumigation experiment. The influence of enhanced minerals supply on the 'acute yellowing' syndrome was additionally investigated in already ailing spruce material removed from its site. (MG).

  12. Depletion of ozone layer and health

    International Nuclear Information System (INIS)

    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

  13. Flixweed Is More Competitive than Winter Wheat under Ozone Pollution: Evidences from Membrane Lipid Peroxidation, Antioxidant Enzymes and Biomass

    OpenAIRE

    Li, Cai-Hong; Wang, Tian-Zuo; Li, Yong; Zheng, Yan-Hai; Jiang, Gao-Ming

    2013-01-01

    To investigate the effects of ozone on winter wheat and flixweed under competition, two species were exposed to ambient, elevated and high [O3] for 30 days, planted singly or in mixculture. Eco-physiological responses were examined at different [O3] and fumigating time. Ozone reduced the contents of chlorophyll, increased the accumulation of H2O2 and malondialdehyde in both wheat and flixweed. The effects of competition on chlorophyll content of wheat emerged at elevated and high [O3], while ...

  14. Ambient air quality trends in Alberta

    International Nuclear Information System (INIS)

    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. The dynamics of ozone generation and mode transition in air surface micro-discharge plasma at atmospheric pressure

    International Nuclear Information System (INIS)

    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)

  16. Effect of short term ozone variations on human ultraviolet radiation exposure

    International Nuclear Information System (INIS)

    With recent media reports on the ozone losses or 'hole' over Antarctica, the public, particularly in Australia has become more aware of the relationship between stratospheric ozone losses and increases in terrestrial UV irradiances. Measurements over a 4 day period during April 1999 in Toowoomba (27.5 deg S, 151 .9 deg E, altitude 693m) indicated that the clear sky erythemal UV exposures could increase by 14% with a 4.6% decrease in atmospheric ozone levels. Similar anti-correlation trends between atmospheric ozone levels and UV exposures were also found for this location for other measurement times during 1999. Heightened ambient UV irradiance levels of the magnitude found during the April, 1999 period have been estimated to increase the UV exposure to the human nose from 7.15 MED per day to 8.34 MED per day. Copyright (2000) Australasian Radiation Protection Society Inc

  17. Effects of ozone fumigation on epiphytic macrolichens: ultrastructure, CO2 gas exchange and chlorophyll fluorescence.

    Science.gov (United States)

    Scheidegger, C; Schroeter, B

    1995-01-01

    The lichen species Anaptychia ciliaris, Collema nigrescens, Evernia prunastri, Hypogymnia bitteri, Lobaria pulmonaria, Pseudevernia furfuracea and Usnea rigida s.l. were fumigated with site-relevant concentrations (for Central Europe) of ozone over 80 days (180 microg m(-3) during daytime, 80 microg m(-3) during the night). Chlorophyll fluorescence measurements revealed a significant reduction of Fv/Fm after ozone fumigation in five of the species investigated, indicating severe stress on photosystem II due to ozone. The physiological impairment paralleled our fine structural investigations, revealing a significantly higher percentage of collapsed photobiont cells. This indicates that the effects of ambient ozone concentrations under experimental conditions included biophysical and physiological, as well as structural impairment in the lichens studied. PMID:15091548

  18. Transcriptional signatures in leaves of adult European beech trees (Fagus sylvatica L.) in an experimentally enhanced free air ozone setting

    International Nuclear Information System (INIS)

    Tropospheric ozone causes severe oxidative stress in plants. To investigate