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Sample records for delta prd region

  1. Regional Integrated Experiments on Air Quality over Pearl River Delta 2004 (PRIDE-PRD2004): Overview

    Science.gov (United States)

    Zhang, Y. H.; Hu, M.; Zhong, L. J.; Wiedensohler, A.; Liu, S. C.; Andreae, M. O.; Wang, W.; Fan, S. J.

    The aims of the Program of Regional Integrated Experiments on Air Quality over Pearl River Delta of China 2004 (PRIDE-PRD2004) were to characterize in depth the pollution, and to improve the understanding of the chemical and radiative processes in the atmosphere of Pearl River Delta (PRD) in South-Eastern China. This comprehensive program integrated ground-base in situ measurements, vertical observations (including aircraft) and model simulations. The intensive field campaign was conducted from 4 October to 5 November 2004 at two super-sites: an urban site in Guangzhou city (23.13°N, 113.26°E) and a non-urban site at Xinken (22.61°N, 113.59°E). They were coordinated with concurrent meteorological observations as well as measurements at stations of a regional monitoring network. Quality control and quality assurances, application of closure studies and observation-based modeling were the key elements of the research strategies for the PRIDE-PRD2004 campaign. Knowledge and understanding of the important issues, including 3-D distribution of air pollution, ozone formation process and its control strategies, sources of volatile organic compounds, chemical and physical characteristics and radiative properties of aerosols, and the important role of nitrous acid atmospheric chemistry, have been improved substantially by this study.

  2. Volatile Organic Compound (VOC measurements in the Pearl River Delta (PRD region, China

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    Chih-chung Chang

    2008-03-01

    Full Text Available We measured levels of ambient volatile organic compounds (VOCs at seven sites in the Pearl River Delta (PRD region of China during the Air Quality Monitoring Campaign spanning 4 October to 3 November 2004. Two of the sites, Guangzhou (GZ and Xinken (XK, were intensive sites at which we collected multiple daily canister samples. The observations reported here provide a look at the VOC distribution, speciation, and photochemical implications in the PRD region. Alkanes constituted the largest percentage (>40% in mixing ratios of the quantified VOCs at six sites; the exception was one major industrial site that was dominated by aromatics (about 52%. Highly elevated VOC levels occurred at GZ during two pollution episodes; however, the chemical composition of VOCs did not exhibit noticeable changes during these episodes. We calculated the OH loss rate to estimate the chemical reactivity of all VOCs. Of the anthropogenic VOCs, alkenes played a predominant role in VOC reactivity at GZ, whereas the contributions of reactive aromatics were more important at XK. Our preliminary analysis of the VOC correlations suggests that the ambient VOCs at GZ came directly from local sources (i.e., automobiles; those at XK were influenced by both local emissions and transportation of air mass from upwind areas.

  3. Process analysis and sensitivity study of regional ozone formation over the Pearl River Delta, China, during the PRIDE-PRD2004 campaign using the CMAQ model

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    X. Wang

    2009-12-01

    Full Text Available In this study, the Community Multiscale Air Quality (CMAQ modeling system is used to simulate the ozone (O3 episodes during the Program of Regional Integrated Experiments of Air Quality over the Pearl River Delta, China, in October 2004 (PRIDE-PRD2004. The simulation suggests that O3 pollution is a regional phenomenon in the PRD. Elevated O3 levels often occurred in the southwestern inland PRD, Pearl River estuary (PRE, and southern coastal areas during the 1-month field campaign. Three evolution patterns of simulated surface O3 are summarized based on different near-ground flow conditions. More than 75% of days featured interaction between weak synoptic forcing and local sea-land circulations. Integrated process rate (IPR analysis shows that photochemical production is the dominant contributor to O3 enhancement from 09:00 to 15:00 LST (local standard time in the atmospheric boundary layer over most areas with elevated O3 occurrence in the mid-afternoon. The simulated ozone production efficiency is 2–8 O3 molecules per NOx molecule oxidized in areas with high O3 chemical production. Precursors of O3 originating from different source regions in the central PRD are mixed during transport to downwind rural areas during nighttime and early morning, where they then contribute to the daytime O3 photochemical production. Such close interactions among precursor emissions, transports, and O3 photochemical production result in the regional O3 pollution over the PRD. Sensitivity studies suggest that O3 formation is volatile organic compound-limited in the central inland PRD, PRE, and surrounding coastal areas with less chemical aging (NOx/NOy>0.6, but is NOx-limited in the rural southwestern PRD with photochemically aged air (NOx/NOy<0.3.

  4. Modeling of air quality with a modified two-dimensional Eulerian model: A case study in the Pearl River Delta (PRD) region of China

    Institute of Scientific and Technical Information of China (English)

    CHENG Yan-li; BAI Yu-hua; LI Jin-long; LIU Zhao-rong

    2007-01-01

    A modified two-dimensional Eulerian air quality model was used to simulate both the gaseous and particulate pollutant concentrations during October 21-24, 2004 in the Pearl River Delta (PRD) region, China. The most significant improvement to the model is the added capability to predict the secondary organic aerosols (SOA) concentrations because of the inclusion of the SOA formation chemistry. The meteorological input data were prepared using the CALMET meteorological model. The concentrations of aerosol-bound species such as NO3-, NH4+, SO42-, and SOA were calculated in the fine particle size range (<2.5 μm). The results of the two-dimensional model were compared to the measurements at the ground level during the PRD Intensive Monitoring Campaign (IMC). Overall, there were good agreements between the measured and modeled concentrations of inorganic aerosol components and O3. Both the measured and the modeled results indicated that the maximum hourly O3 concentrations exceeded the China National Air Quality Standard. The predicted 24-h average SOA concentrations were in reasonable agreement with those predicted by the method of minimum OC/EC ratio.

  5. Process analysis and sensitivity study of regional ozone formation over the Pearl River Delta, China, during the PRIDE-PRD2004 campaign using the Community Multiscale Air Quality modeling system

    Directory of Open Access Journals (Sweden)

    X. Wang

    2010-05-01

    Full Text Available In this study, the Community Multiscale Air Quality (CMAQ modeling system is used to simulate the ozone (O3 episodes during the Program of Regional Integrated Experiments of Air Quality over the Pearl River Delta, China, in October 2004 (PRIDE-PRD2004. The simulation suggests that O3 pollution is a regional phenomenon in the Pearl River Delta (PRD. Elevated O3 levels often occurred in the southwestern inland PRD, Pearl River estuary (PRE, and southern coastal areas during the 1-month field campaign. Three evolution patterns of simulated surface O3 are summarized based on different near-ground flow conditions. More than 75% of days featured interactions between weak synoptic forcing and local sea-land circulation. Integrated process rate (IPR analysis shows that photochemical production is a dominant contributor to O3 enhancement from 09:00 to 15:00 local standard time in the atmospheric boundary layer over most areas with elevated O3 occurrence in the mid-afternoon. The simulated ozone production efficiency is 2–8 O3 molecules per NOx molecule oxidized in areas with high O3 chemical production. Precursors of O3 originating from different source regions in the central PRD are mixed during the course of transport to downwind rural areas during nighttime and early morning, where they then contribute to the daytime O3 photochemical production. The sea-land circulation plays an important role on the regional O3 formation and distribution over PRD. Sensitivity studies suggest that O3 formation is volatile-organic-compound-limited in the central inland PRD, PRE, and surrounding coastal areas with less chemical aging (NOx/NOy>0.6, but is NOx-limited in the rural southwestern PRD with aged air (NOx/NOy<0.3.

  6. Light absorption of brown carbon aerosol in the PRD region of China

    Science.gov (United States)

    Yuan, J.-F.; Huang, X.-F.; Cao, L.-M.; Cui, J.; Zhu, Q.; Huang, C.-N.; Lan, Z.-J.; He, L.-Y.

    2016-02-01

    The strong spectral dependence of light absorption of brown carbon (BrC) aerosol is regarded to influence aerosol's radiative forcing significantly. The Absorption Angstrom Exponent (AAE) method has been widely used in previous studies to attribute light absorption of BrC at shorter wavelengths for ambient aerosols, with a theoretical assumption that the AAE of "pure" black carbon (BC) aerosol equals to 1.0. In this study, the AAE method was applied to both urban and rural environments in the Pearl River Delta (PRD) region of China, with an improvement of constraining the realistic AAE of "pure" BC through statistical analysis of on-line measurement data. A three-wavelength photo-acoustic soot spectrometer (PASS-3) and aerosol mass spectrometers (AMS) were used to explore the relationship between the measured AAE and the relative abundance of organic aerosol to BC. The regression and extrapolation analysis revealed that more realistic AAE values for "pure" BC aerosol (AAEBC) were 0.86, 0.82, and 1.02 between 405 and 781 nm, and 0.70, 0.71, and 0.86 between 532 and 781 nm, in the campaigns of urbanwinter, urbanfall, and ruralfall, respectively. Roadway tunnel experiments were conducted and the results further confirmed the representativeness of the obtained AAEBC values for the urban environment. Finally, the average light absorption contributions of BrC (± relative uncertainties) at 405 nm were quantified to be 11.7 % (±5 %), 6.3 % (±4 %), and 12.1 % (±7 %) in the campaigns of urbanwinter, urbanfall, and ruralfall, respectively, and those at 532 nm were 10.0 % (±2 %), 4.1 % (±3 %), and 5.5 % (±5 %), respectively. The relatively higher BrC absorption contribution at 405 nm in the ruralfall campaign could be reasonably attributed to the biomass burning events nearby, which was then directly supported by the biomass burning simulation experiments performed in this study. This paper indicates that the BrC contribution to total aerosol light absorption at shorter

  7. Urbanization signatures in strong versus weak precipitation over the Pearl River Delta metropolitan regions of China

    Energy Technology Data Exchange (ETDEWEB)

    Li Weibiao; Chen Sheng; Wen Zhiping; Wang Baomin [Department of Atmospheric Sciences, Sun Yat-sen University, Guangzhou 510275 (China); Chen Guixing; Sha Weimin [Department of Geophysics, Graduate School of Science, Tohoku University, Sendai (Japan); Luo Cong; Feng Yerong, E-mail: eeslwb@mail.sysu.edu.cn [Guangzhou Central Meteorological observatory, Guangzhou 510080 (China)

    2011-07-15

    We assess the issues of urban effects on the precipitation over the Pearl River Delta (PRD) metropolitan regions of China. The spatial and temporal variations of strong versus weak precipitation over the PRD and surrounding nonurban areas are investigated. The results show that the urbanization signatures in strong precipitation are significantly different from those in weak precipitation over the urban areas. The PRD experiences more strong precipitation but less weak precipitation compared to surrounding nonurban regions. In addition, the strong precipitation over the PRD displays a pronounced seasonal variation. The seasonality of weak precipitation, however, is much weaker over the PRD compared to the surrounding nonurban regions. Moreover, a strengthening in the precipitation intensity, a reduction in the rainfall frequency and an increase in the convective precipitation as well as the afternoon precipitation are found over the urban areas, which are probably associated with the abundance in strong precipitation and the deficit in weak precipitation over the PRD.

  8. Sources of excess urban carbonaceous aerosol in the Pearl River delta region, China

    Science.gov (United States)

    Carbonaceous aerosol is one of the important constituents of fine particulate matter (PM2.5) in Southern China, including the Pearl River Delta (PRD) region and Hong Kong (HK). During the study period (October and December of 2002, and March and June of 2003), the monthly average...

  9. The contributions of biomass burning to primary and secondary organics: A case study in Pearl River Delta (PRD), China.

    Science.gov (United States)

    Wang, BaoLin; Liu, Ying; Shao, Min; Lu, SiHua; Wang, Ming; Yuan, Bin; Gong, ZhaoHeng; He, LingYan; Zeng, LiMin; Hu, Min; Zhang, YuanHang

    2016-11-01

    Synchronized online measurements of gas- and particle- phase organics including non-methane hydrocarbons (NMHCs), oxygenated volatile organic compounds (OVOCs) and submicron organic matters (OM) were conducted in November 2010 at Heshan, Guangdong provincial supersite, China. Several biomass burning events were identified by using acetonitrile as a tracer, and enhancement ratios (EnRs) of organics to carbon monoxide (CO) obtained from this work generally agree with those from rice straw burning in previous studies. The influences of biomass burning on NMHCs, OVOCs and OM were explored by comparing biomass burning impacted plumes (BB plumes) and non-biomass burning plumes (non-BB plumes). A photochemical age-based parameterization method was used to characterize primary emission and chemical behavior of those three organic groups. The emission ratios (EmRs) of NMHCs, OVOCs and OM to CO increased by 27-71%, 34-55% and 67% in BB plumes, respectively, in comparison with non-BB plumes. The estimated formation rate of secondary organic aerosol (SOA) in BB plumes was found to be 24% faster than non-BB plumes. By applying the above emission ratios to the whole PRD, the annual emissions of VOCs and OM from open burning of crop residues would be 56.4 and 3.8Gg in 2010 in PRD, respectively.

  10. Chemical and stable carbon isotopic composition of PM2.5 from on-road vehicle emissions in the PRD region and implication for vehicle emission control policy

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    S. Dai

    2014-11-01

    Full Text Available Vehicle emission is a major source of urban air pollution. In recent decade, the Chinese government has introduced a range of policies to reduce the vehicle emission. In order to understand the chemical characteristics of PM2.5 from on-road vehicle emission in the Pearl River Delta (PRD region and to evaluate the effectiveness of control policies on vehicles emission, the emission factors of PM2.5 mass, elemental carbon (EC, organic carbon (OC, water-soluble organic carbon (WSOC, water-soluble inorganic ions (WSII, metal elements, organic compounds and stable carbon isotopic composition were measured in the Zhujiang Tunnel of Guangzhou, the PRD region of China in 2013. Emission factors of PM2.5 mass, OC, EC, and WSOC were 92.4, 16.7, 16.4, and 1.31 mg vehicle−1 km−1 respectively. Emission factors of WSII were 0.016 (F- ~4.17 (Cl- mg vehicle−1 km−1, totally contributing about 9.8% to the PM2.5 emissions. The sum of 27 measured metal elements accounted for 15.2% of the PM2.5 emissions. Fe was the most abundant metal element, with an emission factor of 3.91 mg vehicle−1 km−1. Emission factors of organic compounds including n-alkanes, PAHs, hopanes, and steranes were 91.9, 5.02, 32.0 and 7.59 μg vehicle−1 km−1, respectively. Stable carbon isotopic composition δ13C value was measured and it was −25.0‰ on average. An isotopic fractionation of 3.2‰ was found during fuel combustion. Compared with a previous study in Zhujiang Tunnel in year 2004, emission factors of PM2.5 mass, EC, OC, WSII except Cl-, and organic compounds decreased by 16.0–93.4%, which could be attributed to emission control policy from 2004 to 2013. However, emission factors of most of the metal elements increased significantly, which could be partially attributed to the changes in motor oil additives and vehicle condition. There are no mandatory national standards to limit metal content from vehicle emission, which should be a concern of the government. A

  11. Impacts of Weather Conditions Modified by Urban Expansion on Surface Ozone:Comparison between the Pearl River Delta and Yangtze River Delta Regions

    Institute of Scientific and Technical Information of China (English)

    WANG Xuemei; CHEN Fei; WU Zhiyong; ZHANG Meigen; Mukul TEWARI; Alex GUENTHER; Christine WIEDINMYER

    2009-01-01

    In this paper,the online weather research and forecasting and chemistry (WRF-Chem) model is used to explore the impacts of urban expansion on regional weather conditions and its implication on surface ozone concentrations over the Pearl River Delta(PRD) and Yangtze River Delta(YRD) regions.Two scenarios of urban maps are used in the WRF-Chem to represent the early 1990s (pre-urbanization) and the current urban distribution in the PRD and the YRD.Month-long simulation results using the above land-use scenarios for March 2001 show that urbanization increases both the day- and night-time 2-m temperatures by about 0.6℃ and 1.4℃,respectively. Daytime reduction in the wind speed by about 3.0 m s-1 is larger than that for the nighttime (0.5 to 2 m s-1).The daytime increase in the PBL height (>200 m) is also larger than the nighttime (50-100 m).The meteorological conditions modified by urbanization lead to detectable ozone-concentration changes in the PRD and the YRD.Urbanization increases the nighttime surface-ozone concentrations by about 4.7%-8.5% and by about 2.9%-4.2% for the daytime.In addition to modifying individual meteorological variables,urbanization also enhances the convergence zones,especially in the PRD.More importantly,urbanization has different effects on the surface ozone for the PRD and the YRD,presumably due to their urbanization characteristics and geographical locations.Even though the PRD has a smaller increase in the surface temperature than the YRD,it has (a) weaker surface wind speed,(b)smaller increase in PBL heights,and (c) stronger convergence zones.The latter three factors outweighed the temperature increase and resulted in a larger ozone enhancement in the PRD than the YRD.

  12. Assessment of Spatial Distribution and Submerged Scope for Storm Surge in the Pearl River Delta Region

    Institute of Scientific and Technical Information of China (English)

    LI Kuo; LI Guo-sheng

    2011-01-01

    The aim of this study was to explore the spatial distribution and submerged scope for storm surge in the Pearl River Delta (PRD) region.Based on the data of storm surges in the PRD region in the past 30 years, the return periods of 12 tide-gauge stations for storm surges were calculated separately with the methods of Gumbel and Pearson-iii.The data of another six tide-gauge stations in Guangdong Coast was quoted to depict the overall features of storm surges in Guangdong.Using least-square method, the spatial distribution models of storm surges in different retum periods were established to reveal the distribution rule of the set-up values of storm surges.The spatial distribution curves of storm surges in different retum periods in the PRD Region were drawn up based on the models and the terrain of Guangdong Coast.According to the curves, the extreme set-up values of storm surges in 1 000,100, 10 a return periods were determined on each spot of Guangdong Coast.Applying the spatial analysis technology of ArcGIS, with the topography data of the PRD Region, the submerged scopes of flood caused by storm surge in 1 000, 100, 10 a return periods were drawn up.The loss caused by storm surges was estimated.Results showed that the storm surges and the topography of PRD region jointly led to the serious flood in the PRD region.This assessment would be useful for the planning and design department to make decision and provide government scientific basis for storm surge prediction, coastal engineering designing and the prevention of storm surge disaster.

  13. Health impact assessment of marine emissions in Pearl River Delta region.

    Science.gov (United States)

    Lai, H K; Tsang, H; Chau, J; Lee, C H; McGhee, S M; Hedley, A J; Wong, C M

    2013-01-15

    Global marine vessels emissions are adversely affecting human health particularly in southeast Asia. But health burdens from both ocean- and river-going vessels in Pearl River Delta (PRD) regions are not quantified. We estimated the potential health impacts using pooled relative risks of mortality and hospital admissions in China, and the model derived concentrations of sulfur dioxide (SO₂), particulate matter (PM₁₀), nitrogen dioxide (NO₂) and ozone (O₃) due to vessels emissions. SO₂ concentrations due to marine emissions in Hong Kong were 13.6 μg m⁻³ compared with 0.7 μg m⁻³ in PRD regions that were far from the marine vessels. In PRD regions, the estimated annual numbers (per million people) of excess deaths from all natural causes and hospital admissions from cardiorespiratory causes attributable to SO₂, NO₂, O₃ and PM₁₀ combined from marine emissions were 45 and 265 respectively. Marine emission control measures could contribute a large reduction in mortality and hospital admissions in PRD regions especially in Hong Kong.

  14. Impacts of urbanization on nitrogen deposition in the Pearl River Delta region, China

    Science.gov (United States)

    Wang, X.; Fan, Q.

    2015-12-01

    The Pearl River Delta (PRD) region is one of the most advanced economic districts in China, which has experienced remarkable economic development and urbanization in the past two decades. Accompanied with the rapid economy development and urbanization, the PRD region encountered both severe nitrogen pollution and deposition. In this study, the characteristics of nitrogen deposition and impacts of urbanization on nitrogen deposition in the PRD region were investigated by combining the methods of field study and numerical model. According to the field measurements, the total dry and wet atmospheric deposition of reactive N at a urban site (SYSU) was up to 55.0 kg ha-1 yr-1 in 2010, slightly lower than the results at a rural forest site (DHS) (57.6 kg ha-1 yr-1). Wet deposition was the main form of the total deposition (64-76%). Organic nitrogen (ON) was found to be dominant in the total N deposition, with a contribution of 53% at DHS and 42% at SYSU. NH4+-N and NO3--N accounted for a similar portion of the total N deposition (23-29%). Atmospheric nitrogen deposition was further simulated by using the improved WRF-Chem model. The simulated N deposition flux was high in the north of PRD (i.e., Guangzhou, Foshan, Zhaoqing) and relative low in the east (Huizhou) and south (Zhuhai), with an average N deposition flux of about 24 kg ha-1 yr-1 for the whole PRD. The distribution of N dry deposition was mainly controlled by the concentration of reactive N compounds and precipitation governed the wet deposition distribution. The modeling results also indicate that the PRD area is the source region in which the emissions exceed the deposition while the outside area of the PRD is the receptor region in which the deposition exceeds emissions. The impact of emission change and land use change due to urbanization was also investigated using the WRF-Chem model. The results showed that atmospheric N deposition exhibits a direct response to emission change while the land use change

  15. Sources of excess urban carbonaceous aerosol in the Pearl River Delta Region, China

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, M.; Wang, F.; Hagler, G.S.W.; Hou, X.M.; Bergin, M.; Cheng, Y.A.; Salmon, L.G.; Schauer, J.J.; Louie, P.K.K.; Zeng, L.M.; Zhang, Y.H. [Peking University, Beijing (China). College of Environmental Science & Engineering

    2011-02-15

    Carbonaceous aerosol is one of the important constituents of fine particulate matter (PM2.5) in southern China, including the Pearl River Delta (PRD) region and Hong Kong (HK). During the study period (October and December of 2002, and March and June of 2003), the monthly average organic carbon (OC) ranged from 3.52 to 7.87 {mu} g m{sup -3} in Hong Kong and 4.14-20.19 {mu} g m{sup -3} in the PRD from simultaneous measurements at three sites in HK and four sites in the PRO. Compared to the PRD, the spatial distribution of carbonaceous aerosol in Hong Kong was relatively homogeneous. Sources contributing to excess OC in the PRO were examined, which is the difference between OC concentrations measured at the PRD sites to the average level in Hong Kong. Eight primary sources contributing to excess OC were identified with chemical mass balance modeling in a combination with molecular markers analyzed by gas chromatography/mass spectrometry. Excess OC at Guangzhou, the capital city of Guangdong province, was consistently high, ranging from 9.77 to 13.6 {mu} g m{sup -3}. Four primary sources including gasoline engine exhaust, diesel engine exhaust, biomass burning, and coal combustion accounted for more than 50% of excess OC in the PRD, especially in December (up to 76%). Mobile source emissions alone can contribute about 30% of excess OC. The unexplained or other excess OC was the highest at the rural site, but in general less than 20% at other sites. The coal combustion source contribution was unique in that it exhibited relatively homogeneous spatial distribution, indicating it was still an important source of carbonaceous aerosol in the PRD (17% of excess OC) during the study period.

  16. Importance of NOx control for peak ozone reduction in the Pearl River Delta region

    Science.gov (United States)

    Li, Ying; Lau, Alexis K. H.; Fung, Jimmy C. H.; Zheng, Junyu; Liu, Shawchen

    2013-08-01

    As major air pollutants and key precursors of several secondary air pollutants, nitrogen oxide (NOx) emissions are regulated in many countries. However, NOx control increases ozone concentrations when the ozone formation regime is volatile organic compound (VOC) limited. Although many studies have shown that NOx regulation reduces ozone levels over the long term, it is still of concern that NOx regulation increases short-term ozone levels in metropolitan regions, where ozone formation is found to be predominantly VOC-limited. The Pearl River Delta (PRD) in China is such a region. Our modeling sensitivity study shows that while NOx reduction in the PRD region may raise the mean ozone concentration, it can also decrease peak ozone levels. Similar changes are observed in the NOx and ozone data of the PRD regional air quality monitoring network (2006-2012), lending further credence to our results. In the model, this NOx control effect is a result of the complicated spatial and diurnal variations of the ozone formation regime. In most of the PRD region, the formation regime is VOC-limited in the morning and becomes NOx-limited during peak ozone hours. Although some areas are always VOC-limited, their ozone concentrations are relatively low, and the ozone increases caused by NOx reduction generally do not cause higher ozone levels than the region's original ozone maxima. Several control scenarios are simulated to evaluate the effects of various possible control regulations. Our results show that in addition to VOC control, NOx control can be effective for reducing peak ozone concentrations in the PRD region.

  17. [Distribution of Regional Pollution and the Characteristics of Vertical Wind Field in the Pearl River Delta].

    Science.gov (United States)

    Liu, Jian; Wu, Dui; Fan, Shao-jia

    2015-11-01

    Based on the data of hourly PM2.5 concentration of 56 environmental monitoring stations and 9 cities over the Pearl River Delta (PRD) region, the distributions of PM2.5 pollution in PRD region were analyzed by systematic cluster analysis and correlational analysis. It was found that the regional pollution could be divided into 3 types. The first type was the pollution occurred in Dongguan, Guangzhou, Foshan and Jiangmen (I type), and the second type was the pollution occurred in Zhongshan, Zhuhai, Shenzhen and Huizhou (II type), while the last type was the pollution only occurred in Zhaoqing (III type). During the study period, they occurred 47, 7 and 128 days, respectively. During events of pollution type I, except Zhuhai, Shenzhen and Huizhou, the PM2.5 concentrations of other cities were generally high, while the PM2.5 concentration in whole PRD region was over 50.0 μg x m(-3) during events of pollution type II. The regions with higher PM2.5 concentration was mainly concentrated in Zhaoqing, Guangzhou and Foshan during events of pollution type III. The wind data from 4 wind profile radars located in PRD region was used to study the characteristics of vertical wind field of these 3 pollution types. It was found that the wind profiles of type I and III were similar that low layer and high layer were controlled by the southeast wind and the southwest wind, respectively. For type II, the low layer and high layer were influenced by northerly wind and westerly wind, respectively. Compared with other types, the wind speed and ventilation index of type II. were much higher, and the variation of wind direction at lower-middle-layer was much smaller. When PRD region was influenced by northerly winds, the PM2.5 concentration in the entire PRD region was higher. When PRD region was controlled by southeast wind, the PM2.5 concentrations of I and II areas were relatively lower, while the pollution in III area was relatively heavier.

  18. Impacts of seasonal and regional variability in biogenic VOC emissions on surface ozone in the Pearl River Delta region, China

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    S. Situ

    2013-03-01

    Full Text Available In this study, the BVOC emissions in November 2010 over the Pearl River Delta (PRD region in southern China have been estimated by the latest version of a Biogenic Volatile Organic Compound (BVOC emission model (MEGAN v2.1. The evaluation of MEGAN performance at a representative forest site within this region indicates MEGAN can estimate BVOC emissions reasonably well in this region except overestimating isoprene emission in autumn for reasons that are discussed in this manuscript. Along with the output from MEGAN, the Weather Research and Forecasting model with chemistry (WRF-Chem is used to estimate the impacts of BVOC emissions on surface ozone in the PRD region. The results show BVOC emissions increase the daytime ozone peak by ~3 ppb on average, and the max hourly impacts of BVOC emissions on the daytime ozone peak is 24.8 ppb. Surface ozone mixing ratios in the central area of Guangzhou-Foshan and the western Jiangmen are most sensitive to BVOC emissions BVOCs from outside and central PRD influence the central area of Guangzhou-Foshan and the western Jiangmen significantly while BVOCs from rural PRD mainly influence the western Jiangmen. The impacts of BVOC emissions on surface ozone differ in different PRD cities, and the impact varies in different seasons. Foshan and Jiangmen being most affected in autumn, result in 6.0 ppb and 5.5 ppb increases in surface ozone concentrations, while Guangzhou and Huizhou become more affected in summer. Three additional experiments concerning the sensitivity of surface ozone to MEGAN input variables show that surface ozone is more sensitive to landcover change, followed by emission factors and meteorology.

  19. Impacts of seasonal and regional variability in biogenic VOC emissions on surface ozone in the Pearl River Delta region, China

    Energy Technology Data Exchange (ETDEWEB)

    Situ, S.; Guenther, Alex B.; Wang, X. J.; Jiang, X.; Turnipseed, A.; Wu, Z.; Bai, J.; Wang, X.

    2013-12-05

    In this study, the BVOC emissions in November 2010 over the Pearl River Delta (PRD) region in southern China have been estimated by the latest version of a Biogenic Volatile Organic Compound (BVOC) emission model (MEGAN v2.1). The evaluation of MEGAN performance at a representative forest site within this region indicates MEGAN can estimate BVOC emissions reasonably well in this region except overestimating isoprene emission in autumn for reasons that are discussed in this manuscript. Along with the output from MEGAN, the Weather Research and Forecasting model with chemistry (WRF-Chem) is used to estimate the impacts of BVOC emissions on surface ozone in the PRD region. The results show BVOC emissions increase the daytime ozone peak by *3 ppb on average, and the max hourly impacts of BVOC emissions on the daytime ozone peak is 24.8 ppb. Surface ozone mixing ratios in the central area of Guangzhou- Foshan and the western Jiangmen are most sensitive to BVOC emissions BVOCs from outside and central PRD influence the central area of Guangzhou-Foshan and the western Jiangmen significantly while BVOCs from rural PRD mainly influence the western Jiangmen. The impacts of BVOC emissions on surface ozone differ in different PRD cities, and the impact varies in different seasons. Foshan and Jiangmen being most affected in autumn, result in 6.0 ppb and 5.5 ppb increases in surface ozone concentrations, while Guangzhou and Huizhou become more affected in summer. Three additional experiments concerning the sensitivity of surface ozone to MEGAN input variables show that surface ozone is more sensitive to landcover change, followed by emission factors and meteorology.

  20. Assessing the Atmospheric Oxygen Balance in a Region of Rapid Urbanization: A Case Study in the Pearl River Delta, China

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    Jian Peng

    2015-09-01

    Full Text Available Oxygen is a product of photosynthesis and is essential for human survival. It also has a profound effect on ecosystems as the atmospheric oxygen balance is the basis for regional ecological sustainability. The Pearl River Delta (PRD has experienced rapid urbanization and has become one of China’s three major urban agglomerations. This study focused on the oxygen balance of the PRD in 2011, and established a model to calculate the oxygen balance that was suitable for a region of rapid urbanization by applying remote sensing gross primary production data via the C-Fix model. The influencing factors for the oxygen imbalance were analyzed and it was suggested that more attention be paid to the management of oxygen emissions than oxygen consumption. The results indicated that the oxygen balance capacity of the PRD was weak, with an oxygen consumption 9.37 times that of its oxygen emission. Zhaoqing and Huizhou are the main sources of oxygen in the PRD, with an oxygen emission density more than 4.67 times that of Dongguan or Zhuhai. Guangzhou and Shenzhen are the main oxygen sinks, with a total oxygen consumption more than 5.49 times that of Zhaoqing. Moreover, the oxygen balance of the PRD is more sensitive to oxygen emissions than consumption. Therefore, it could be inferred that the land urbanization has a stronger influence on the oxygen balance than the population urbanization.

  1. Modeling of HCHO and CHOCHO at a semi-rural site in southern China during the PRIDE-PRD2006 campaign

    OpenAIRE

    Li, Xin; F. Rohrer; T. Brauers; Hofzumahaus, A.; Lu, K.; Shao, M.; Zhang, Y.H.; Wahner, A.

    2013-01-01

    HCHO and CHOCHO are important trace gases in the atmosphere, serving as tracers of VOCs oxidations. In the past decade, high concentrations of HCHO and CHOCHO have been observed for the Pearl River Delta (PRD) region in southern China. In this study, we performed box model simulations of HCHO and CHOCHO at a semi-rural site in PRD, focusing on understanding their sources and sinks and factors influencing the CHOCHO to HCHO ratio (RGF). The model was constrained by the simultaneous measurement...

  2. Modeling of HCHO and CHOCHO at a semi-rural site in southern China during the PRIDE-PRD2006 campaign

    OpenAIRE

    Li, X.; F. Rohrer; T. Brauers; Hofzumahaus, A.; Lu, K.; Shao, M.; Zhang, Y.H.; Wahner, A.

    2014-01-01

    HCHO and CHOCHO are important trace gases in the atmosphere, serving as tracers of VOC oxidations. In the past decade, high concentrations of HCHO and CHOCHO have been observed for the Pearl River Delta (PRD) region in southern China. In this study, we performed box model simulations of HCHO and CHOCHO at a semi-rural site in the PRD, focusing on understanding their sources and sinks and factors influencing the CHOCHO to HCHO ratio (RGF). The model was constrained by the ...

  3. Investigation of the sources and formation mechanisms of regional haze in autumn over Pearl River Delta region, China

    Science.gov (United States)

    Zhou, S.; Wang, X.; Fan, Q.; Fan, S.; Chen, L.; Chang, M.; Huang, M.

    2015-12-01

    China has experienced severe haze and visibility degradation problems in recent years accompanying with rapid urbanization and industrialization. In this study, daily fine aerosol samples were concurrently collected during 01-29 October, 2014 in four sites (2 urban sites, 1 upwind site and 1 downwind site) in the Pearl River Delta (PRD) region (Figure 1), a mega metropolitan area and manufacturing hub in south China. Main chemical components of PM2.5 including sulfate, nitrate, ammonium, organic carbon, element carbon and elements, as well as individual particles morphology and mixing state and atmospheric boundary layer information were obtained and analyzed to investigate the sources and evolution mechanisms of typical haze events in the PRD region. The preliminary results showed that daily average PM2.5 concentrations varied from 25.4 to 174.8 μg m-3 with an average PM2.5 concentration of 64.5 μg m-3. We noted that PM2.5 concentrations in the downwind site were slightly higher than those in the upwind and urban sites during the haze episodes, indicating the formation and evolution of fine particles during the transport. Further detailed studies, including interpreting observational data and WRF/Chem model simulation, will be carried out to understand the sources and evolution mechanisms of the typical autumn regional haze in the PRD region.

  4. THE REGIONAL DEVELOPMENT IN THE PEARL RIVER DELTA IN NEW TERM

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Since China opening to outside world, the economy inthe Pearl(Zhujiang) River Delta(PRD) has been dou-ble digit growth. It has been known as one of mature fast growth areas in the world and become the model and hope of Chi-nese reform and opening to outside world. The regional development in PRD is the outcome of polarization effects. The polar-ization effects actually are extension of international regional division and a combination of Hongkong's influence and re-form and open-door policies on the mainland. Since the 1990s, driven by knowledge-based economy, the PRD has furtheradjusted the industrial structure and achieved good progress in upgrading industrial structure. Its high technology industryhas developed quickly and the economic internationalization has deepened, meanwhile, the region is going through transforma-tion and some new trends have begun to appear, which include: university towns springing up, industrial globalization andthe construction of Hi-tech development zones. The paper suggests that with the economic growth changing from relying onthe low level production elements to relying on high level production elements, the regional policies in GuangdongProvince should develop correspondingly: 1 ) make a plan to prohibite the blind construction in innovative spatial construc-tions; 2) make measures to attract the overseas talents to establish a pool of talent; 3) work out the favorable policies forabsorbing larger capital; 4) formulate the policy of attracting a cluster of industries to speed up the upgrade of industrialdevelopment.

  5. Science-policy interplay: Air quality management in the Pearl River Delta region and Hong Kong

    Science.gov (United States)

    Zhong, Liuju; Louie, Peter K. K.; Zheng, Junyu; Yuan, Zibing; Yue, Dingli; Ho, Josephine W. K.; Lau, Alexis K. H.

    2013-09-01

    The information provided by the scientific studies and control measures implemented in the Pearl River Delta (PRD) region of China reveals that tremendous progress has been made in the understanding of regional air pollution issues and the deployment of mitigation measures for alleviating these problems. Given the unparalleled rapid economic growth in the PRD over the past two decades, such progress was only made possible by strong, science-based support and the partnerships between government and research institutions in the region and overseas. Researchers from these partnership programs and related studies have deployed cutting-edge expertise and experience in various crucial mainland China and mainland China/Hong Kong-level projects. China recognizes the importance of protecting the environment and cleaning up the air in the pursuit of sustainable growth and economic development. To avoid falling into a cycle of event-driven clean-up efforts, China has recently taken a major step and updated the national ambient air quality standards. Clearly, China is implementing an increasing number of evidence-based policies to address air pollution problems. Thus, to bring a fresh impetus at a national level, the PRD must maintain and augment the Hong Kong-mainland collaborative momentum, inducing a "whole-China" effort to clean up air pollution. To strengthen the science-based support system and ensure continuous and concerted effort in implementing the regional multi-pollutant control strategy, there must be an overarching and integral Hong Kong-Guangdong science consortium framework supporting the formulation of regional policy and control measures built on common goals under the "one country, two systems" principle. The "PRD Approach" of the air quality management regime reflected regional cooperative efforts in synchronous air pollutant control, catalyzed the crucial role of information disclosure and subtly transformed the air quality management approach to overcome

  6. Public health and medical care for the world's factory: China's Pearl River Delta Region

    Directory of Open Access Journals (Sweden)

    Rodwin Victor G

    2011-10-01

    Full Text Available Abstract While the growth of urbanization, worldwide, has improved the lives of migrants from the hinterland, it also raises health risks related to population density, concentrated poverty and the transmission of infectious disease. Will megacity regions evolve into socially infected breeding grounds for the rapid transmission of disease, or can they become critical spatial entities for the protection and promotion of population health? We address this question for the Pearl River Delta Region (PRD based on recent data from Chinese sources, and on the experience of how New York, Greater London, Tokyo and Paris have grappled with the challenges of protecting population health and providing their populations with access to health care services. In some respects, there are some important lessons from comparative experience for PRD, notably the importance of covering the entire population for health care services and targeting special programs for those at highest risk for disease. In other respects, PRD's growth rate and sheer scale make it a unique megacity region that already faces new challenges and will require new solutions.

  7. VOCs and OVOCs distribution and control policy implications in Pearl River Delta region, China

    Science.gov (United States)

    Louie, Peter K. K.; Ho, Josephine W. K.; Tsang, Roy C. W.; Blake, Donald R.; Lau, Alexis K. H.; Yu, Jian Zhen; Yuan, Zibing; Wang, Xinming; Shao, Min; Zhong, Liuju

    2013-09-01

    Ambient air measurements of volatile organic compounds (VOCs) and oxygenated volatile organic compounds (OVOCs) were conducted and characterised during a two-year grid study in the Pearl River Delta (PRD) region of southern China. The present grid study pioneered the systematic investigation of the nature and characteristics of complex VOC and OVOC sources at a regional scale. The largest contributing VOCs, accounting over 80% of the total VOCs mixing ratio, were toluene, ethane, ethyne, propane, ethene, butane, benzene, pentane, ethylbenzene, and xylenes. Sub-regional VOC spatial characteristics were identified, namely: i) relatively fresh pollutants, consistent with elevated vehicular and industrial activities, around the PRD estuary; and ii) a concentration gradient with higher mixing ratios of VOCs in the west as compared with the eastern part of PRD. Based on alkyl nitrate aging determination, a high hydroxyl radical (OH) concentration favoured fast hydrocarbon reactions and formation of locally produced ozone. The photochemical reactivity analysis showed aromatic hydrocarbons and alkenes together consisted of around 80% of the ozone formation potential (OFP) among the key VOCs. We also found that the OFP from OVOCs should not be neglected since their OFP contribution was more than one-third of that from VOCs alone. These findings support the choice of current air pollution control policy which focuses on vehicular sources but warrants further controls. Industrial emissions and VOCs emitted by solvents should be the next targets for ground-level ozone abatement.

  8. Numerical model to quantify biogenic volatile organic compound emissions: The Pearl River Delta region as a case study.

    Science.gov (United States)

    Wang, Xuemei; Situ, Shuping; Chen, Weihua; Zheng, Junyu; Guenther, Alex; Fan, Qi; Chang, Ming

    2016-08-01

    This article compiles the actual knowledge of the biogenic volatile organic compound (BVOC) emissions estimated using model methods in the Pearl River Delta (PRD) region, one of the most developed regions in China. The developed history of BVOC emission models is presented briefly and three typical emission models are introduced and compared. The results from local studies related to BVOC emissions have been summarized. Based on this analysis, it is recommended that local researchers conduct BVOC emission studies systematically, from the assessment of model inputs, to compiling regional emission inventories to quantifying the uncertainties and evaluating the model results. Beyond that, more basic researches should be conducted in the future to close the gaps in knowledge on BVOC emission mechanisms, to develop the emission models and to refine the inventory results. This paper can provide a perspective on these aspects in the broad field of research associated with BVOC emissions in the PRD region.

  9. Source apportionment for sediment PAHs using hybrid genetic pattern search treatment of a chemical mass balance receptor model: application to the Pearl River Delta region, China.

    Science.gov (United States)

    Wu, Jin; Teng, Yanguo; Chen, Haiyang

    2014-10-01

    In order to solve the collinear problem and improve the estimation accuracy of the chemical mass balance (CMB) model which can be essentially regarded as a constrained optimization process, in this study, a hybrid genetic pattern search algorithm (HGPS) was proposed and applied to apportion the source contributions for sediment polycyclic aromatic hydrocarbons (PAHs) in the Pearl River Delta (PRD) region, China. Simulation results with developed synthetic datasets indicated that the estimated source contributions by HGPS were more close to the true values than CMB8.2. Utilizing the HGPS-CMB, residential coal and traffic tunnel were apportioned as the major sources of sediment PAHs in the PRD region. For freshwater surface sediments, the average contribution from residential coal ranged from 32 to 55%, and traffic tunnel ranged from 13 to 33%, while the major sources for marine sediments were traffic tunnel (10 ~ 56%). These results provide information for developing better PAH pollution control strategies for the PRD.

  10. Occurrence and distribution of phthalate esters in riverine sediments from the Pearl River Delta region, South China.

    Science.gov (United States)

    Liu, Hong; Cui, Kunyan; Zeng, Feng; Chen, Lixuan; Cheng, Yating; Li, Huiru; Li, Shuocong; Zhou, Xi; Zhu, Fang; Ouyang, Gangfeng; Luan, Tiangang; Zeng, Zunxiang

    2014-06-15

    Sixty-eight sediment samples collected from Dongjiang River, Xijiang River, Beijiang River and Zhujiang River in the Pearl River Delta (PRD) region, Southern China, were analyzed for 16 phthalate esters (PAEs). PAEs were detected in all riverine sediments analyzed, which indicate that PAEs are ubiquitous environmental contaminants. The Σ16PAEs concentrations in riverine sediments in the PRD region ranged from 0.567 to 47.3 μg g(-1) dry weight (dw), with the mean and median concentrations of 5.34 μg g(-1) dw and 2.15 μg g(-1) dw, respectively. Elevated PAEs concentrations in riverine sediments in the PRD region were found in the highly urbanized and industrialized areas. Of the 16 PAEs, diisobutyl phthalate (DiBP), di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP) dominated the PAEs, with the mean and median concentrations of 1.12 μg g(-1)dw, 0.420 μg g(-1) dw and 3.72 μg g(-1) dw, and 0.429 μg g(-1) dw, 0.152 μg g(-1) dw and 1.55 μg g(-1) dw, respectively, and accounted for 94.2-99.7% of the Σ16PAEs concentrations. Influenced by local sources and the properties of PAEs, a gradient trend of concentrations and a fractionation of composition from more to less industrialized and urbanized areas were discovered. As compared to the results from other studies, the riverine sediments in the PRD region were severely contaminated with PAEs. Information about PAEs contamination status and its effect on the aquatic organisms in the PRD region may deserve further attention.

  11. Appraising sustainable flood risk management in the Pearl River Delta's coastal megacities: A case study of Hong Kong, China

    OpenAIRE

    Chan, F. K. S.; Adekola, O. A.; Mitchell, G.; McDonald, A. T.

    2013-01-01

    The Pearl River Delta (PRD) region has experienced rapid economic and population growth in the last three decades. The delta includes coastal megacities, such as Hong Kong. These low-lying urbanised coastal regions in the PRD are vulnerable to flood risks from unpredictable climatic conditions. These can result in increasing storm surges, rising sea level and intensified rainstorms causing coastal and inland flooding, all of which impact the delta. This paper has taken the coastal megacity of...

  12. Characterization of secondary aerosol and its extinction effects on visibility over the Pearl River Delta Region, China.

    Science.gov (United States)

    Deng, Xuejiao; Wu, Dui; Yu, Jianzhen; Lau, Alexis K H; Li, Fei; Tan, Haobo; Yuan, Zibing; Ng, Wai Man; Deng, Tao; Wu, Cheng; Zhou, Xiuji

    2013-09-01

    Aerosol samples collected from July 2007 to March 2008 were used to obtain major aerosol constituents in an urban location in the Pearl River Delta Region (PRD), China. The minimum organic carbon (OC)/elemental carbon (EC) ratio was used to calculate the primary and secondary organic carbon and the extinction effect of the secondary aerosol on visibility was estimated. As indicated in the analysis, the mass of secondary aerosol takes up 50% of the total mass of PM2.5; the OC/EC ratio is larger than 2 and there are significant characteristics of secondary aerosol generation; the levels of secondary OC are comparable with those of sulfate; and there is obvious enrichment of secondary aerosol on more polluted days. In a dry environment, the extinction weight is 59% for the secondary aerosol, while it is as high as 82% if the environment is highly humid (relative humidity [RH] = 95%). The hygroscopic growth of the aerosol can reduce visibility greatly; the secondary aerosol shares much larger quotas on more polluted days. For the Pearl River Delta (PRD), secondary aerosol and carbonaceous aerosol, especially secondary organic carbon (SOC), are a very acute problem; the study of the generating mechanism and sources for secondary aerosol is the key to the effort of controlling visibility in this region. The equation set forth in IMPROVE experiments can only be referenced but is not applicable to evaluate the extinction effect of individual aerosol components on visibility in the PRD region.

  13. Process analysis of regional aerosol pollution during spring in the Pearl River Delta region, China

    Science.gov (United States)

    Fan, Qi; Lan, Jing; Liu, Yiming; Wang, Xuemei; Chan, Pakwai; Hong, Yingying; Feng, Yerong; Liu, Yexin; Zeng, Yanjun; Liang, Guixiong

    2015-12-01

    A numerical simulation analysis was performed for three air pollution episodes in the Pearl River Delta (PRD) region during March 2012 using the third-generation air quality modeling system Models-3/CMAQ. The results demonstrated that particulate matter was the primary pollutant for all three pollution episodes and was accompanied by relatively low visibility in the first two episodes. Weather maps indicate that the first two episodes occurred under the influence of warm, wet southerly air flow systems that led to high humidity throughout the region. The liquid phase reaction of gaseous pollutants resulted in the generation of fine secondary particles, which were identified as the primary source of pollution in the first two episodes. The third pollution episode occurred during a warming period following a cold front. Relative humidity was lower during this episode, and coarse particles were the major pollution contributor. Results of process analysis indicated that emissions sources, horizontal transport and vertical transport were the primary factors affecting pollutant concentrations within the near-surface layer during all three episodes, while aerosol processes, cloud processes, horizontal transport and vertical transport had greater influence at approximately 900 m above ground. Cloud processes had a greater impact during the first two pollution episodes because of the higher relative humidity. In addition, by comparing pollution processes from different cities (Guangzhou and Zhongshan), the study revealed that the first two pollution episodes were the result of local emissions within the PRD region and transport between surrounding cities, while the third episode exhibited prominent regional pollution characteristics and was the result of regional pollutant transport.

  14. Assessment of heavy metals/metalloid (As, Pb, Cd, Ni, Zn, Cr, Cu, Mn) concentrations in edible fish species tissue in the Pearl River Delta (PRD), China.

    Science.gov (United States)

    Leung, H M; Leung, A O W; Wang, H S; Ma, K K; Liang, Y; Ho, K C; Cheung, K C; Tohidi, F; Yung, K K L

    2014-01-15

    The major aim of this study was to investigate heavy metal content of edible fish in the PRD. Eleven species of fish (consisting of 711 individuals) [catfish (Clarias fuscus), tilapia (Oreochromis mossambicus), grass carp (Ctenopharyngodon idellus), bighead carp (Aristichthys nobilis), mandarin fish (Siniperca kneri), snakehead (Channa asiatiea), black bass (Micropterus salmoides), mangrove snapper (Lutjanus griseus), star snapper (Lutjanu stellatus), snubnose pompano (Trachinotus blochii) and orange-spotted grouper (Epinephelus coioides)] were collected for the analyses of heavy metals. Overall concentrations (mg/kg, ww) in the fish muscles were: As (0.03-1.53), Pb (0.03-8.62), Cd (0.02-0.06), Ni (0.44-9.75), Zn (15.7-29.5), Cr (0.22-0.65), Cu (0.79-2.26), Mn (0.82-6.91). Significant level of Pb were found in tilapia at all locations. It is recommended that heavy metal concentrations in different fish species must be determined on a regular basis in the future so as to reduce human health risks from acute and chronic food intoxication.

  15. Assessing Long-Term Trend of Particulate Matter Pollution in the Pearl River Delta Region Using Satellite Remote Sensing.

    Science.gov (United States)

    Li, Ying; Lin, Changqing; Lau, Alexis K H; Liao, Chenghao; Zhang, Yongbo; Zeng, Wutao; Li, Chengcai; Fung, Jimmy C H; Tse, Tim K T

    2015-10-06

    Serious particulate matter (PM) pollution problems in many polluted regions of China have been frequently reported in recent years. Long-term exposure to ambient PM pollution is significantly associated with adverse health effects. Characterizing the long-term trends and variation in PM pollution is a basic requirement for evaluating long-term exposure and for guiding future policies to reduce the effects of air pollution on health. However, long-term, ground-based PM measurements are only available at a few fixed stations. In this study, an algorithm is developed and validated to estimate PM concentrations based on the satellite atmospheric optical depth with 1 km spatial resolution. The long-term trends of PM10 concentrations in the entire Pearl River Delta (PRD) region and different cities are quantified and discussed. From 2001 to 2013, the PM10 pollution of the entire PRD region was dominated by a decreasing trend of -0.15 ± 0.23 μg/m(3)·yr. This decreasing PM10 trend was apparent over 75% of the PRD area, with the most significant decreases observed in the center of the region. However, the remaining 25%, mostly located in the outskirts of the region, showed an increasing PM10 trend. This overall decreasing trend indicates the effectiveness of the control measures applied in the past decade for the primary pollutants.

  16. An ozone episode over the Pearl River Delta in October 2008

    Science.gov (United States)

    Shen, Jin; Zhang, Yuanhang; Wang, Xuesong; Li, Jinfeng; Chen, Hao; Liu, Run; Zhong, Liuju; Jiang, Ming; Yue, Dingli; Chen, Duohong; Lv, Wei

    2015-12-01

    The north and east Pearl River Delta (PRD) is usually a clean, upwind area in autumn. Serious ozone pollution there in mid-late October 2008 was first discovered and then analyzed. Trajectory analysis, process analysis, ozone source apportionment technology, and sensitivity analysis were used to study this episode. Under the influence of a weak south wind, the precursors emitted in Guangzhou and Foshan were transported to the north and northeast PRD and formed ozone there, which resulted in high ozone concentration (>100 ppb). As the wind direction later transited to northerly, the precursors in the northeast PRD that originated from the central and west PRD were transported to the south, and caused severe ozone pollution in the southeast PRD. The ozone contributed by chemical processes reached >20 ppb/h in Jinguowan. More than 40 ppb ozone was contributed by the precursor emission in the central and west PRD during the episode. The ozone concentration was highly sensitive to the precursor emission in the PRD region in the high-ozone situations. This episode showed the complexity of regional pollution in the PRD. When the PRD is controlled by a low air pressure system and then cold air moves from northern China to the south, the risk of ozone pollution in the north and southeast PRD increases.

  17. Behaviors of extreme water level in the Pearl River Delta and possible impacts from human activities

    Directory of Open Access Journals (Sweden)

    Y. D. Chen

    2007-12-01

    Full Text Available Trends and variations of the extreme water levels defined as exceeding/falling below certain thresholds (mean ± std across the Pearl River Delta (PRD are systematically explored using the linear regression method. Research results indicate that: 1 The upper PRD is dominated by the significant decreasing low water level, and significant increasing low water level can be identified in the lower PRD. The variations of the relative frequency of the high water level are characterized by the decreasing variability in the middle PRD. However more stations show significant changes of the relative frequency of the low water level across the PRD. No confirmative changing patterns of the relative frequency of the low water level can be detected in the middle PRD; 2 When it comes to the seasonal variations of the high/low water level in JJA (high flow periods in the PRD, stations located closer to the estuary tend to exhibit increasing high/low water level. However stations located closer to the upper PRD tend to show decreasing high/low water level. Similar patterns can be identified in the high/low water level in DJF (low flow periods in the PRD; 3 The changes of the water level in the PRD are heavily affected by human interferences, e.g. in-channel dredging, sand mining and the construction of levees. The stations dominated by decreasing water level are mostly located along the river channels featured by highly-intensive dredging. The stations along the coastal regions show significant increasing extreme high/low water level. The coastal regions are not influenced by in-channel dredging, and furthermore, sediment loads from upper and middle PRD are deposited in the river mouths and which will tend to raise the water level in the estuary of the PRD. The findings of this paper may be helpful for local water resource management.

  18. Black carbon measurements in the Pearl River Delta region of China

    Science.gov (United States)

    Huang, X.; Gao, R.; Schwarz, J. P.; Ling-Yan, H.; Fahey, D. W.; Laurel A, W.; Zeng, L.

    2009-12-01

    The Pearl River Delta (PRD) region in southeastern China is one of the most polluted industrial/metropolitan areas in the world. The 3C-STAR campaign (Synthesized Prevention Techniques for Air Pollution Complex and Integrated Demonstration in Key City-Cluster Region), carried out in October-November, 2008, was aimed at improving the understanding and quantification of air pollution in the region, while developing technical capacity for regional air quality monitoring and modeling. We report single-particle soot photometer (SP2) measurements and analyses of refractory black carbon (rBC) at Kaiping, a rural site downwind of the major pollution sources in the PRD area. The rBC mass loadings varied between 0.5 and 10 µg-rBC kg-air-1, and averaged 2.8 µg-rBC kg-air-1. These values are roughly an order of magnitude higher than those measured in the Houston, Texas, a major US metropolitan area. The rBC mass distributions show a primary lognormal peak with a median mass diameter of 0.22 µm volume-equivalent diameter (VED), which is similar to those observed in Houston and other regions with the SP2 instrument. A second mode with a mass median diameter of 0.69 µm VED, has not been observed before. Coatings are found on over 50% of rBC particles, suggesting that they are aged and/or of biomass-burning origin. The high rBC loadings cause significant heating of the atmosphere due to direct solar absorption. A diurnal heating rate of over 0.5 K day-1. is estimated for the average of entire dataset with a maximum heating rate near 3 K day-1.

  19. Investigating the Impacts of Landuse-landcover (LULC) Change in the Pearl River Delta Region on Water Quality in the Pearl River Estuary and Hong Kong’s Coast

    OpenAIRE

    Hongyan Xi; Yuanzhi Zhang; Yunpeng Wang; Yufei Wang

    2009-01-01

    Water quality information in the coastal region of Hong Kong and the Pearl River Estuary (PRE) is of great concern to the local community. Due to great landuse-landcover (LULC) changes with rapid industrialization and urbanization in the Pearl River Delta (PRD) region, water quality in the PRE has worsened during the last 20 years. Frequent red tide and harmful algal blooms have occurred in the estuary and its adjacent coastal waters since the 1980s and have caused important economic losses, ...

  20. Urbanization effect on precipitation over the Pearl River Delta based on CMORPH data

    Directory of Open Access Journals (Sweden)

    Sheng Chen

    2015-03-01

    Full Text Available Based on the satellite data from the Climate Prediction Center morphing (CMORPH at very high spatial and temporal resolution, the effects of urbanization on precipitation were assessed over the Pearl River Delta (PRD metropolitan regions of China. CMORPH data well estimates the precipitation features over the PRD. Compared to the surrounding rural areas, the PRD urban areas experience fewer and shorter precipitation events with a lower precipitation frequency (ratio of rainy hours, about 3 days per year less; however, short-duration heavy rain events play a more significant role over the PRD urban areas. Afternoon precipitation is much more pronounced over the PRD urban areas than the surrounding rural areas, which is probably because of the increase in short-duration heavy rain over urban areas.

  1. Seasonal variations of anhydrosugars in PM2.5 in the Pearl River Delta Region, China

    Directory of Open Access Journals (Sweden)

    Kin Fai Ho

    2014-06-01

    Full Text Available Anhydrosugars including levoglucosan and mannosan are the most effective organic tracers for biomass burning aerosol in the atmosphere. In this study, to investigate the contribution of biomass burning emissions to the aerosol burden in the Pearl River Delta (PRD region, China, 24-hour integrated PM2.5 samples were collected simultaneously at four locations, (i Guangzhou (GZ, (ii Zhaoqing (ZQ in Guangdong province, (iii Hok Tsui (HT and (iv Hong Kong Polytechnic University (PU in Hong Kong, in four seasons between 2006 and 2007. Levoglucosan and mannosan, together with water-soluble inorganic ions and water-soluble organic carbon (WSOC, were determined to elucidate the seasonal and spatial variations in biomass burning contributions. The concentrations of levoglucosan and mannosan were on average 82.4±123 and 5.8±8.6 ng m−3, respectively. The WSOC concentrations ranged from 0.2 to 9.4 µg m−3, with an average of 2.1±1.6 µg m−3. The relative contributions of biomass burning emissions to OC were 33% in QZ, 12% in GZ, 4% at PU and 5% at HT, respectively, estimated by the measured levoglucosan to organic carbon ratio (LG/OC relative to literature-derived LG/OC values. The contributions from biomass burning emissions were in general 1.7–2.8 times higher in winter than those in other seasons. Further, it was inferred from diagnostic tracer ratios that a significant fraction of biomass burning emissions was derived from burning of hard wood and likely also from field burning of agricultural residues, such as rice straw, in the PRD region. Our results highlight the contributions from biomass/biofuel burning activities on the regional aerosol budget in South China.

  2. Impact of Precursor Levels and Global Warming on Peak Ozone Concentration in the Pearl River Delta Region of China

    Institute of Scientific and Technical Information of China (English)

    WEI Xiaolin; LIU Qian; Ka Se LAM; WANG Tijian

    2012-01-01

    The relationship between the emission of ozone precursors and the chemical production of tropospheric ozone (O3) in the Pearl River Delta Region (PRD) was studied using numerical simulation.The aim of this study was to examine the volatile organic compound (VOC)- or nitrogen oxide (NOx =NO+NO2)-limited conditions at present and when surface temperature is increasing due to global warming,thus to make recommendations for future ozone abatement policies for the PRD region.The model used for this application is the U.S.Environmental Protection Agency's (EPA's) third-generation air-quality modeling system; it consists of the mesoscale meteorological model MM5 and the chemical transport model named Community Multi-scale Air Quality (CMAQ).A series of sensitivity tests were conducted to assess the influence of VOC and NOx variations on ozone production.Tropical cyclone was shown to be one of the important synoptic weather patterns leading to ozone pollution.The simulations were based on a tropicalcyclone-related episode that occurred during 14-16 September 2004.The results show that,in the future,the control strategy for emissions should be tightened. To reduce the current level of ozone to meet the Hong Kong Environmental Protection Department (EPD) air-quality objective (hourly average of 120 ppb),emphasis should be put on restricting the increase of NOx emissions. Furthermore,for a wide range of possible changes in precursor emissions,temperature increase will increase the ozone peak in the PRD region; the areas affected by photochemical smog are growing wider,but the locations of the ozone plume are rather invariant.

  3. Impacts of thermal circulations induced by urbanization on ozone formation in the Pearl River Delta region, China

    Science.gov (United States)

    Li, Mengmeng; Song, Yu; Mao, Zhichun; Liu, Mingxu; Huang, Xin

    2016-02-01

    Thermal circulations induced by urbanization could exert important effects on regional ozone (O3) formation through regulating the chemical transformations and transport of O3 and its precursors. In this study, the Weather Research and Forecasting/Chemistry (WRF/Chem) model combined with remote sensing are used to investigate the impacts of urbanization-induced circulations on O3 formation in the Pearl River Delta (PRD) region, China. The urban heat island (UHI) effect in PRD significantly enhances turbulent mixing and modifies local circulations, i.e., initiates the UHI circulation and strengthens the sea breeze, which in turn cause a detectable decrease of daytime O3 concentration (-1.3 ppb) and an increase of O3 (+5.2 ppb) around the nocturnal rush-hours. The suppressed O3 titration destruction due to NOx dilution into the deeper urban boundary layer (200-400 m) is the main reason for elevated nocturnal O3 levels. In the daytime, however, the upward transport of O3 precursors weakens near-surface O3 photochemical production and conversely enhances upper-level O3 generation. Furthermore, the surface UHI convergence flow and intensified sea breeze act to effectively trap O3 at the suburban and coastal regions.

  4. A refined 2010-based VOC emission inventory and its improvement on modeling regional ozone in the Pearl River Delta Region, China.

    Science.gov (United States)

    Yin, Shasha; Zheng, Junyu; Lu, Qing; Yuan, Zibing; Huang, Zhijiong; Zhong, Liuju; Lin, Hui

    2015-05-01

    Accurate and gridded VOC emission inventories are important for improving regional air quality model performance. In this study, a four-level VOC emission source categorization system was proposed. A 2010-based gridded Pearl River Delta (PRD) regional VOC emission inventory was developed with more comprehensive source coverage, latest emission factors, and updated activity data. The total anthropogenic VOC emission was estimated to be about 117.4 × 10(4)t, in which on-road mobile source shared the largest contribution, followed by industrial solvent use and industrial processes sources. Among the industrial solvent use source, furniture manufacturing and shoemaking were major VOC emission contributors. The spatial surrogates of VOC emission were updated for major VOC sources such as industrial sectors and gas stations. Subsector-based temporal characteristics were investigated and their temporal variations were characterized. The impacts of updated VOC emission estimates and spatial surrogates were evaluated by modeling O₃ concentration in the PRD region in the July and October of 2010, respectively. The results indicated that both updated emission estimates and spatial allocations can effectively reduce model bias on O₃ simulation. Further efforts should be made on the refinement of source classification, comprehensive collection of activity data, and spatial-temporal surrogates in order to reduce uncertainty in emission inventory and improve model performance.

  5. Summer and winter variations of dicarboxylic acids, fatty acids and benzoic acid in PM2.5 in Pearl Delta River Region, China

    Directory of Open Access Journals (Sweden)

    K. Kawamura

    2010-11-01

    Full Text Available Ground-based PM2.5 samples collected in Pearl River Delta (PRD region during winter and summer (from 14 December 2006 to 28 January 2007 in winter and from 4 July 2007 to 9 August 2007 in summer were analyzed for 30 water-soluble organic species, including dicarboxylic acids, ketocarboxylic acids and dicarbonyls, nine fatty acids, and benzoic acid. Molecular distributions of dicarboxylic acids demonstrated that oxalic acid (C2 was the most abundant species followed by phthalic acid (Ph in PRD region. The concentrations of total dicarboxylic acids ranged from 99 to 1340 ng m−3, with an average of 438 ± 267 ng m−3 in PRD. The concentrations of total ketocarboxylic acids ranged from 0.6 to 207 ng m−3 (43 ± 48 ng m−3 on average while the concentrations of total α-dicarbonyls, including glyoxal and methylglyoxal, ranged from 0.2 to 89 ng m−3, with an average of 11 ± 18 ng m−3 in PRD. The total quantified water-soluble organic carbon (TQWOC accounted for 3.4 ± 2.2% of OC and 14.3 ± 10.3% of water-soluble OC (WSOC. Hexadecanoic acid (C16:0, octadecanoic acid (C18:0 and oleic acid (C18:1 are the three most abundant fatty acids in PRD. The distributions of fatty acids are characterized by a strong even carbon number predominance with a maximum (Cmax at hexadecanoic acid (C16:0. Ratio of C18:1 to C18:0 acts as an indicator for aerosol aging. In PRD, an average of C18:1/C18:0 ratio was 0.53 ± 0.39, suggesting an enhanced photochemical degradation of unsaturated fatty acid. Seasonal variations of the pollutant concentrations were found in the four sampling cities. Higher concentrations of TQWOC were observed in winter (544 ng m−3 than in summer (318 ng m−3. However, the abundances of TQWOC in OC mass were higher in summer (1.8–12.4%, 5.4% on average than in winter (1.1–5.7, 2.6% on average, being consistent with enhanced secondary production of dicarboxylic acids in warmer weather. Spatial variations of water-soluble dicarboxylic

  6. The Source, Spatial Distribution and Risk Assessment of Heavy Metals in Soil from the Pearl River Delta Based on the National Multi-Purpose Regional Geochemical Survey.

    Science.gov (United States)

    Zhang, Lingyan; Guo, Shuhai; Wu, Bo

    2015-01-01

    The data on the heavy metal content at different soil depths derived from a multi-purpose regional geochemical survey in the Pearl River Delta (PRD) were analyzed using ArcGIS 10.0. By comparing their spatial distributions and areas, the sources of heavy metals (Cd, Hg, As and Pb) were quantitatively identified and explored. Netted measuring points at 25 ×25 km were set over the entire PRD according to the geochemical maps. Based on the calculation data obtained from different soil depths, the concentrations of As and Cd in a large area of the PRD exceeded the National Second-class Standard. The spatial disparity of the geometric centers in the surface soil and deep soil showed that As in the surface soil mainly came from parent materials, while Cd had high consistency in different soil profiles because of deposition in the soil forming process. The migration of Cd also resulted in a considerable ecological risk to the Beijiang and Xijiang River watershed. The potential ecological risk index followed the order Cd ≥ Hg > Pb > As. According to the sources, the distribution trends and the characteristics of heavy metals in the soil from the perspective of the whole area, the Cd pollution should be repaired, especially in the upper reaches of the Xijiang and Beijiang watershed to prevent risk explosion while the pollution of Hg and Pb should be controlled in areas with intense human activity, and supervision during production should be strengthened to maintain the ecological balance of As.

  7. [Numerical modeling analysis of secondary organic aerosol (SOA) combined with the ground-based measurements in the Pearl River Delta region].

    Science.gov (United States)

    Guo, Xiao-Shuang; Situ, Shu-Ping; Wang, Xue-Mei; Ding, Xiang; Wang, Xin-Ming; Yan, Cai-Qing; Li, Xiao-Ying; Zheng, Mei

    2014-05-01

    Two simulations were conducted with different secondary organic aerosol (SOA) methods-VBS (volatile basis set) approach and SORGAM (secondary organic aerosol model) , which have been coupled in the WRF/Chem (weather research and forecasting model with chemistry) model. Ground-based observation data from 18th to 25th November 2008 were used to examine the model performance of SOA in the Pearl River Delta(PRD)region. The results showed that VBS approach could better reproduce the temporal variation and magnitude of SOA compared with SORGAM, and the mean absolute deviation and correlation coefficient between the observed and the simulated data using VBS approach were -4.88 microg m-3 and 0.91, respectively, while they were -5.32 microg.m-3 and 0. 18 with SORGAM. This is mainly because the VBS approach considers SOA precursors with a wider volatility range and the process of chemical aging in SOA formation. Spatiotemporal distribution of SOA in the PRD from the VBS simulation was also analyzed. The results indicated that the SOA has a significant diurnal variation, and the maximal SOA concentration occurred at noon and in the early afternoon. Because of the transport and the considerable spatial distribution of O3 , the SOA concentrations were different in different PRD cities, and the highest concentration of SOA was observed in the downwind area, including Zhongshan, Zhuhai and Jiangmen.

  8. Light Absorption of Brown Carbon Aerosol in the Pearl River Delta Region of China

    Science.gov (United States)

    Huang, X.

    2015-12-01

    X.F. Huang, J.F. Yuan, L.M. Cao, J. Cui, C.N. Huang, Z.J. Lan and L.Y. He Key Laboratory for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, ChinaCorresponding author. Tel.: +86 755 26032532; fax: +86 755 26035332. E-mail address: huangxf@pku.edu.cn (X. F. Huang). Abstract: The strong spectral dependence of light absorption of brown carbon (BrC) aerosol has been recognized in recent decades. The Absorption Angstrom Exponent (AAE) of ambient aerosol was widely used in previous studies to attribute light absorption of brown carbon at shorter wavelengths, with a theoretical assumption that the AAE of black carbon (BC) aerosol equals to unit. In this study, the AAE method was improved by statistical extrapolation based on ambient measurements in the polluted seasons in typical urban and rural areas in the Pearl River Delta (PRD) region of China. A three-wavelength photoacoustic soot spectrometer (PASS-3) and an aerosol mass spectrometer (AMS) were used to explore the relationship between the ambient measured AAE and the ratio of organic aerosol to BC aerosol, in order to extract the more realistic AAE by pure BC aerosol, which were found to be 0.86, 0.82 and 1.02 at 405nm and 0.70, 0.71, and 0.86 at 532nm in the campaigns of urban-winter, urban-fall, and rural-fall, respectively. Roadway tunnel experiment results further supported the effectiveness of the obtained AAE for pure BC aerosol. In addition, biomass burning experiments proved higher spectral dependence of more-BrC environment and further verified the reliability of the instruments' response. Then, the average light absorption contribution of BrC aerosol was calculated to be 11.7, 6.3 and 12.1% (with total relative uncertainty of 7.5, 6.9 and 10.0%) at 405nm and 10.0, 4.1 and 5.5% (with total relative uncertainty of 6.5, 8.6 and 15.4%) at 532nm of the three campaigns, respectively. These results indicate that the

  9. Estimate of anthropogenic halocarbon emission based on measured ratio relative to CO in the Pearl River Delta region, China

    Science.gov (United States)

    Shao, M.; Huang, D.; Gu, D.; Lu, S.; Chang, C.; Wang, J.

    2011-05-01

    Using a GC/FID/MS system, we analyzed the mixing ratio of 16 halocarbon species in more than 100 air samples collected in 2004 from the Pearl River Delta (PRD) region of southern China. The results revealed that there are elevated mixing ratios for most of halocarbons, especially for HClC = CCl2 (trichloroethylene, TCE), CH2Cl2 (dichloromethane, DCM), CH3 Br (bromomethane), HCFC-22, CHCl3 (trichloromethane), CCl4 (tetrachloromethane), Cl2C = CCl2 (perchloroethylene, PCE), CH3CCl3 (methyl chloroform, MCF), and CFC-12. Comparisons were done with the data from TRACE-P and ALE/GAGE/AGAGE experiments, we found that the large variability in mixing ratios (relative standard deviation ranged from 9.31 % to 96.55 %) of the halocarbons suggested substantial local emissions from the PRD region in 2004. Correlations between the mixing ratio of each species and carbon monoxide (CO) was examined, and then the emission of each halocarbon was quantified based on scaling the optimized CO emission inventory with the slope of the regression line fitted to each species relative to CO. The calculated results revealed that mass of CH2Cl2 (7.0 Gg), CH3CCl3 (6.7 Gg), and Cl2C = CCl2 (2.3 Gg) accounted for about 62.9 % of total halocarbon emissions, it suggested a significant contribution from solvent use in the PRD region. Emissions of HCFC-22 (3.5 Gg), an alternative refrigerant to chlorofluorocarbons (CFCs), were about 2.3 times greater than those of CFC-12 (1.6 Gg). CFC-12 and HCFC-22 accounted for 21.5 % of total emissions of halocarbons, so that the refrigerant would be the second largest source of halocarbons. However, the ratio approach found only minor emissions of CFCs, such as CFC-11, and the emission of CFC-114 and CFC-113 were close to zero. Emissions of other anthropogenic halocarbons, such as CCl4, CHCl3, CH3Br, and CH3Cl, were also estimated. Where possible, the emissions estimated from the measured ratios were compared with results from source inventory techniques, we

  10. Sources of C₂-C₄ alkenes, the most important ozone nonmethane hydrocarbon precursors in the Pearl River Delta region.

    Science.gov (United States)

    Zhang, Yanli; Wang, Xinming; Zhang, Zhou; Lü, Sujun; Huang, Zhonghui; Li, Longfeng

    2015-01-01

    Surface ozone is becoming an increasing concern in China's megacities such as the urban centers located in the highly industrialized and densely populated Pearl River Delta (PRD) region, where previous studies suggested that ozone production is sensitive to VOC emissions with alkenes being important precursors. However, little was known about sources of alkenes. Here we present our monitoring of ambient volatile organic compounds at four representative urban, suburban and rural sites in the PRD region during November-December 2009, which experienced frequent ozone episodes. C2-C4 alkenes, whose total mixing ratios were 11-20% of non-methane hydrocarbons (NMHCs) quantified, accounted for 38-64% of ozone formation potentials (OFPs) and 30-50% of the total hydroxyl radical (OH) reactivity by NMHCs. Ethylene was the most abundant alkene, accounting for 8-15% in total mixing ratios of NMHCs and contributed 25-46% of OFPs. Correlations between C2-C4 alkenes and typical source tracers suggested that ethylene might be largely related to vehicle exhausts and industry activities, while propene and butenes were much more LPG-related. Positive Matrix Factorization (PMF) confirmed that vehicle exhaust and liquefied petroleum gas (LPG) were two major sources that altogether accounted for 52-62%, 58-77%, 73-83%, 68-79% and 73-84% for ethylene, propene, 1-butene, trans-2-butene and cis-2-butene, respectively. Vehicle exhausts alone contributed 32-49% ethylene and 35-41% propene. Industry activities contributed 13-23% ethylene and 7-20% propene. LPG instead contributed the most to butenes (38-65%) and substantially to propene (23-36%). Extensive tests confirmed high fractions of propene and butenes in LPG then used in Guangzhou and in LPG combustion plumes; therefore, limiting alkene contents in LPG would benefit regional ozone control.

  11. Estimation of health and economic costs of air pollution over the Pearl River Delta region in China.

    Science.gov (United States)

    Lu, Xingcheng; Yao, Teng; Fung, Jimmy C H; Lin, Changqing

    2016-10-01

    The Pearl River Delta region (PRD) is the economic growth engine of China and also one of the most urbanized regions in the world. As a two-sided sword, rapid economic development causes air pollution and poses adverse health effects to the citizens in this area. This work estimated the negative health effects in the PRD caused by the four major ambient pollutants (SO2, NO2, O3 and PM10) from 2010 to 2013 by using a log linear exposure-response function and the WRF-CMAQ modeling system. Economic loss due to mortality and morbidity was evaluated by the value of statistical life (VSL) and cost of illness (COI) methods. The results show that the overall possible short-term all-cause mortality due to NO2, O3 and PM10 reached the highest in 2013 with the values being 13,217-22,800. The highest total economic loss, which ranged from 14,768 to 25,305million USD, occurred in 2013 and was equivalent to 1.4%-2.3% of the local gross domestic product. The monthly profile of cases of negative health effects varied by city and the types of ambient pollutants. The ratio of mortality attributed to air pollutants to total population was higher in urban areas than in rural areas. People living in the countryside should consider the possible adverse health effects of urban areas before they plan a move to the city. The results show that the health burden caused by the ambient pollutants over this region is serious and suggest that tighter control policies should be implemented in the future to reduce the level of air pollution.

  12. Investigating the Impacts of Landuse-landcover (LULC Change in the Pearl River Delta Region on Water Quality in the Pearl River Estuary and Hong Kong’s Coast

    Directory of Open Access Journals (Sweden)

    Hongyan Xi

    2009-11-01

    Full Text Available Water quality information in the coastal region of Hong Kong and the Pearl River Estuary (PRE is of great concern to the local community. Due to great landuse-landcover (LULC changes with rapid industrialization and urbanization in the Pearl River Delta (PRD region, water quality in the PRE has worsened during the last 20 years. Frequent red tide and harmful algal blooms have occurred in the estuary and its adjacent coastal waters since the 1980s and have caused important economic losses, also possibly threatening to the coastal environment, fishery, and public health in Hong Kong. In addition, recent literature shows that water nutrients in Victoria Harbor of Hong Kong have been proven to be strongly influenced by both the Pearl River and sewage effluent in the wet season (May to September, but it is still unclear how the PRE diluted water intrudes into Victoria Harbor. Due to the cloudy and rainy conditions in the wet season in Hong Kong, ASAR images will be used to monitor the PRE river plumes and track the intruding routes of PRE water nutrients. In this paper, we first review LULC change in the PRD and then show our preliminary results to analyze water quality spatial and temporal information from remote observations with different sensors in the coastal region and estuary. The study will also emphasizes on time series of analysis of LULC trends related to annual sediment yields and critical source areas of erosion for the PRD region since the 1980s.

  13. Speciated OVOC and VOC emission inventories and their implications for reactivity-based ozone control strategy in the Pearl River Delta region, China.

    Science.gov (United States)

    Ou, Jiamin; Zheng, Junyu; Li, Rongrong; Huang, Xiaobo; Zhong, Zhuangmin; Zhong, Liuju; Lin, Hui

    2015-10-15

    The increasing ground-ozone (O3) levels, accompanied by decreasing SO2, NO2, PM10 and PM2.5 concentrations benefited from air pollution control measures implemented in recent years, initiated a serious challenge to control Volatile Organic Compound (VOC) emissions in the Pearl River Delta (PRD) region, China. Speciated VOC emission inventory is fundamental for estimating Ozone Formation Potentials (OFPs) to identify key reactive VOC species and sources in order to formulate efficient O3 control strategies. With the use of the latest bulk VOC emission inventory and local source profiles, this study developed the PRD regional speciated Oxygenated Volatile Organic Compound (OVOC) and VOC emission inventories to identify the key emission-based and OFP-based VOC sources and species. Results showed that: (1) Methyl alcohol, acetone and ethyl acetate were the major constituents in the OVOC emissions from industrial solvents, household solvents, architectural paints and biogenic sources; (2) from the emission-based perspective, aromatics, alkanes, OVOCs and alkenes made up 39.2%, 28.2%, 15.9% and 10.9% of anthropogenic VOCs; (3) from the OFP-based perspective, aromatics and alkenes become predominant with contributions of 59.4% and 25.8% respectively; (4) ethene, m/p-xylene, toluene, 1,2,4-trimethyl benzene and other 24 high OFP-contributing species were the key reactive species that contributed to 52% of anthropogenic emissions and up to 80% of OFPs; and (5) industrial solvents, industrial process, gasoline vehicles and motorcycles were major emission sources of these key reactive species. Policy implications for O3 control strategy were discussed. The OFP cap was proposed to regulate VOC control policies in the PRD region due to its flexibility in reducing the overall OFP of VOC emission sources in practice.

  14. Implications of changing urban and rural emissions on non-methane hydrocarbons in the Pearl River Delta region of China

    Science.gov (United States)

    Tang, J. H.; Chan, L. Y.; Chan, C. Y.; Li, Y. S.; Chang, C. C.; Wang, X. M.; Zou, S. C.; Barletta, Barbara; Blake, D. R.; Wu, Dui

    2008-05-01

    Guangzhou (GZ) is one of the highly industrialized and economically vibrant cities in China, yet it remains relatively understudied in terms of its air quality, which has become severely degraded. In this study, extensive air sampling campaigns had been conducted at GZ urban sites and in Dinghu Mountain (DM), a rural site, in the Pearl River Delta (PRD) during the spring of 2001 and 2005. Additionally, roadside and tunnel samples were collected in GZ in 2000 and 2005. Later, exhaust samples from liquefied petroleum gas (LPG)- and gasoline-fueled taxis were collected in 2006. All samples were analyzed for C2-C10 non-methane hydrocarbons (NMHCs). NMHC profiles showed significant differences in the exhaust samples between gasoline- and LPG-fueled taxis. Propane (47%) was the dominant hydrocarbon in the exhaust of the LPG-fueled taxis, while ethene (35%) was the dominant one in that of gasoline-fueled taxis. The use of LPG-fueled buses and taxis since 2003 and the leakage from these LPG-fueled vehicles were the major factors for the much higher level of propane in GZ urban area in 2005 compared to 2001. The mixing ratios of toluene, ethylbenzene, m/p-xylene and o-xylene decreased at the GZ and DM sites between 2001 and 2005, especially for toluene in GZ, despite the sharp increase in the number of registered motor vehicles in GZ. This phenomenon was driven in part by the closure of polluting industries as well as the upgrading of the road network in urban GZ and in part by the implementation of more stringent emission standards for polluting industries and motor vehicles in the PRD region.

  15. Study on the atmospheric boundary layer and its influence on regional air quality over the Pearl River delta

    Directory of Open Access Journals (Sweden)

    M. Wu

    2013-03-01

    Full Text Available To study the structure of atmospheric boundary layer (ABL and its influence on regional air quality over the Pearl River delta (PRD, two ABL intensive observations were conducted at Panyu (urban station and Xinken (non-urban station, near estuary of PRD during October 2004 and July 2006, respectively. Based on the ABL intensive observation data analysis, the typical weather condition type associated with poor air quality over PRD could be summarized into two kinds: the warmed period before cold front (WPBCF and the subsidence period controlled by tropical cyclone (SPCTC. Two typical polluted cases (affected by WPBCF and SPCTC, respectively and one clean (not-polluted case were chosen for detail analysis. It was found that the continuously low or calm ground wind would lead to pollutant accumulation. The local circulation, such as sea–land breezes and heat–island circulation, played an important role in these polluted cases. The recirculation was significant in polluted cases; steady transport occurred in the clean case. Ventilation index (VI was quite different between polluted cases and the clean case: in WPBCF cases, the peak VI was from 184 to 3555 m2 s−1; on SPCTC days, the peak VI was from 1066 to 4363 m2 s−1; on the clean day, the peak VI was 10 885 m2 s−1 and much larger than all polluted cases. The 24-h average VI on polluted days was from 169 to 2858 m2 s−1 and also much smaller than that of the clean day. VI is a good reference index for pollution judgment. The peak mixing heights were smaller than 700 m in WPBCF cases, and were smaller than 800 m in SPCTC cases. During WPBCF polluted case, only surface inversion layer appeared. In the period of land breeze, surface inversion layer height was about 50 m, but in the period of sea breeze, surface inversion layer height would increase, and reach the maximum height, which was about 600 m. During SPCTC polluted case, there were several inversion layers that appeared at different

  16. Numerical simulation and analysis of saltwater intrusion lengths in the Pearl River Delta, China

    NARCIS (Netherlands)

    Zhang, W.; Feng, H.; Zheng, J.; Hoitink, A.J.F.; Vegt, van der M.; Zhu, Y.; Cai, H.

    2013-01-01

    In recent years, large-scale saltwater intrusion has been threatening the freshwater supply in the metropolitan cities surrounding the Pearl River delta (PRD). Therefore, a better understanding of the saltwater intrusion process in this region is necessary for local water resource management. In thi

  17. Assessing a cross-border logistics policy using a performance measurement system framework: the case of Hong Kong and the Pearl River Delta region

    Science.gov (United States)

    Wong, David W. C.; Choy, K. L.; Chow, Harry K. H.; Lin, Canhong

    2014-06-01

    For the most rapidly growing economic entity in the world, China, a new logistics operation called the indirect cross-border supply chain model has recently emerged. The primary idea of this model is to reduce logistics costs by storing goods at a bonded warehouse with low storage cost in certain Chinese regions, such as the Pearl River Delta (PRD). This research proposes a performance measurement system (PMS) framework to assess the direct and indirect cross-border supply chain models. The PMS covers four categories including cost, time, quality and flexibility in the assessment of the performance of direct and indirect models. Furthermore, a survey was conducted to investigate the logistics performance of third party logistics (3PLs) at the PRD regions, including Guangzhou, Shenzhen and Hong Kong. The significance of the proposed PMS framework allows 3PLs accurately pinpoint the weakness and strengths of it current operations policy at four major performance measurement categories. Hence, this helps 3PLs further enhance the competitiveness and operations efficiency through better resources allocation at the area of warehousing and transportation.

  18. Salinity Impacts on Agriculture and Groundwater in Delta Regions

    Science.gov (United States)

    Clarke, D.; Salehin, M.; Jairuddin, M.; Saleh, A. F. M.; Rahman, M. M.; Parks, K. E.; Haque, M. A.; Lázár, A. N.; Payo, A.

    2015-12-01

    Delta regions are attractive for high intensity agriculture due to the availability of rich sedimentary soils and of fresh water. Many of the world's tropical deltas support high population densities which are reliant on irrigated agriculture. However environmental changes such as sea level rise, tidal inundation and reduced river flows have reduced the quantity and quality of water available for successful agriculture. Additionally, anthropogenic influences such as the over abstraction of ground water and the increased use of low quality water from river inlets has resulted in the accumulation of salts in the soils which diminishes crop productivity. Communities based in these regions are usually reliant on the same water for drinking and cooking because surface water is frequently contaminated by commercial and urban pollution. The expansion of shallow tube well systems for drinking water and agricultural use over the last few decades has resulted in mobilisation of salinity in the coastal and estuarine fringes. Sustainable development in delta regions is becoming constrained by water salinity. However salinity is often studied as an independent issue by specialists working in the fields of agriculture, community water supply and groundwater. The lack of interaction between these disciplines often results in corrective actions being applied to one sector without fully assessing the effects of these actions on other sectors. This paper describes a framework for indentifying the causes and impacts of salinity in delta regions based on the source-pathway-receptor framework. It uses examples and scenarios from the Ganges-Brahmaputra-Meghna delta in Bangladesh together with field measurements and observations made in vulnerable coastal communities. The paper demonstrates the importance of creating an holistic understanding of the development and management of water resources to reduce the impact of salinity in fresh water in delta regions.

  19. Transverse response functions in the $\\Delta$-resonance region

    CERN Document Server

    Rost, E; Shepard, J R

    1992-01-01

    We calculate transverse response functions for quasi-elastic electron scattering at high momentum transfers in a relativistic Hartree approximation in configuration space. We treat the excitation of the $\\Delta$ resonance using its free mass and width. Good agreement with experiment is found in the dip region.

  20. Sources of secondary organic aerosols in the Pearl River Delta region in fall: Contributions from the aqueous reactive uptake of dicarbonyls

    Science.gov (United States)

    Li, Nan; Fu, Tzung-May; Cao, Junji; Lee, Shuncheng; Huang, Xiao-Feng; He, Ling-Yan; Ho, Kin-Fai; Fu, Joshua S.; Lam, Yun-Fat

    2013-09-01

    We used the regional air quality model CMAQ to simulate organic aerosol (OA) concentrations over the Pearl River Delta region (PRD) and compared model results to measurements. Our goals were (1) to evaluate the potential contribution of the aqueous reactive uptake of dicarbonyls (glyoxal and methylglyoxal) as a source of secondary organic aerosol (SOA) in an urban environment, and (2) to quantify the sources of SOA in the PRD in fall. We improved the representation of dicarbonyl gas phase chemistry in CMAQ, as well as added SOA formation via the irreversible uptake of dicarbonyls by aqueous aerosols and cloud droplets, characterized by a reactive uptake coefficient γ = 2.9 × 10-3 based on laboratory studies. Our model results were compared to aerosol mass spectrometry (AMS) measurements in Shenzhen during a photochemical smog event in fall 2009. Including the new dicarbonyl SOA source in CMAQ led to an increase in the simulated mean SOA concentration at the sampling site from 4.1 μg m-3 to 9.0 μg m-3 during the smog event, in better agreement with the mean observed oxygenated OA (OOA) concentration (8.0 μg m-3). The simulated SOA reproduced the variability of observed OOA (r = 0.89). Moreover, simulated dicarbonyl SOA was highly correlated with simulated sulfate (r = 0.72), consistent with the observed high correlation between OOA and sulfate (r = 0.84). Including the dicarbonyl SOA source also increased the mean simulated concentrations of total OA from 8.2 μg m-3 to 13.1 μg m-3, closer to the mean observed OA concentration (16.5 μg m-3). The remaining difference between the observed and simulated OA was largely due to impacts from episodic biomass burning emissions, but the model did not capture this variability. We concluded that, for the PRD in fall and outside of major biomass burning events, 75% of the total SOA was biogenic. Isoprene was the most important precursor, accounting for 41% of the total SOA. Aromatics accounted for 13% of the total SOA

  1. Sustainable development goals offer new opportunities for tropical delta regions

    OpenAIRE

    2015-01-01

    Marine and lacustrine delta regions constitute only 1% of the Earth's surface but are home to over 500 million people.1 They are key contributors to agricultural production at the national and regional levels and thus enable alleviation of global food insecurity risks. In addition, tropical megadeltas sustain rich ecosystems that provide a variety of services and are noted for high biodiversity and natural resources.2 At the same time, however, their geographical location, coupled with often ...

  2. Construction area expansion in relation to economic-demographic development and land resource in the Pearl River Delta of China

    NARCIS (Netherlands)

    Liu, Zhijia; Huang, Heqing; Werners, Saskia E.; Yan, Dan

    2016-01-01

    Since 1979, the Pearl River Delta (PRD) of China has experienced rapid socioeconomic development along with a fast expansion of construction area. Affected by both natural and human factors, a complex interdependency is found among the regional changes in construction area, GDP and population. A

  3. Coordinated Development between Urban Tourism Economy and Transport in the Pearl River Delta, China

    Directory of Open Access Journals (Sweden)

    Qiuxia Zheng

    2016-12-01

    Full Text Available By selecting the panel data from 2005 to 2014 of 9 cities in the Pearl River Delta (PRD in China, this paper respectively establishes the evaluation index system of tourism economy and transport. It also applies a synthetic evaluation model and coupling coordination model to estimate comprehensive indices of tourism economy and transport system and their coordinated relationships. The results show that: (1 during 2005–2014, the synthetic indices of tourism economy generally presented constantly upward tendency and the synthetic indices of transport represented wave-like raising trend in the PRD region; (2 during 2005–2014, the 9 cities in the PRD region gradually tended to have coordinated development between tourism economy and transport, and the central area of the PRD region developed faster than the flanks; (3 the correlations between the tourism economy and transport of the cities with abundant tourism resources, developed economy, and advanced transport facilities were more remarkable, and the coordination degrees were higher. Besides, macro-policies, mega-events, and locations also impacted on coordinated development between the tourism economy and transport in the PRD region.

  4. Variation trends and influencing factors of total gaseous mercury in the Pearl River Delta-A highly industrialised region in South China influenced by seasonal monsoons

    Science.gov (United States)

    Chen, Laiguo; Liu, Ming; Xu, Zhencheng; Fan, Ruifang; Tao, Jun; Chen, Duohong; Zhang, Deqiang; Xie, Donghai; Sun, Jiaren

    2013-10-01

    Studies on atmospheric mercury in the Pearl River Delta (PRD) region are important because of the economic relevance of this region to China, because of its economic developmental pattern and because it is a highly industrialised area influenced by the strong seasonal monsoons. Total gaseous mercury (TGM), meteorological parameters and criteria pollutant concentrations were measured at Mt. Dinghu (DH, a regional monitoring site) and Guangzhou (GZ, an urban monitoring site) in the PRD region from October 2009 to April 2010 and from November 2010 to November 2011, respectively. The ranges of daily average TGM concentrations at the DH and GZ sites were 1.87-29.9 ng m-3 (5.07 ± 2.89 ng m-3) and 2.66-11.1 ng m-3 (4.60 ± 1.36 ng m-3), respectively, which were far more significant than the background values in the Northern Hemisphere (1.5-1.7 ng m-3), suggesting that the atmosphere in the PRD has suffered from mercury pollution. Similar TGM seasonal distributions at the two sites were observed, with a descending order of spring, winter, autumn and summer. The different seasonal monsoons were the dominant factor controlling the seasonal variability of the TGM, with variations in the boundary layer and oxidation also possibly partially contributing. Different diurnal patterns of the TGM at two sites were observed. TGM levels during the daytime were higher than those during the nighttime and were predominantly influenced by mountain and valley winds at the DH site, whereas the opposite trend was evident at the GZ site, which was primarily influenced by the boundary-layer height and O3 concentration. During the monitoring period, the correlations between the daily TGM levels and the SO2 and NO2 levels at the DH site were significant (r = 0.36, p mercury for this regional monitoring site. At the GZ site, the correlations between the daily TGM level and the NO, NO2, CO levels were significant (r = 0.501, p mercury sources for this urban monitoring site. The TGM distribution

  5. Estimate of anthropogenic halocarbon emission based on measured ratio relative to CO in the Pearl River Delta region, China

    Directory of Open Access Journals (Sweden)

    M. Shao

    2011-05-01

    Full Text Available Using a GC/FID/MS system, we analyzed the mixing ratio of 16 halocarbon species in more than 100 air samples collected in 2004 from the Pearl River Delta (PRD region of southern China. The results revealed that there are elevated mixing ratios for most of halocarbons, especially for HClC = CCl2 (trichloroethylene, TCE, CH2Cl2 (dichloromethane, DCM, CH3 Br (bromomethane, HCFC-22, CHCl3 (trichloromethane, CCl4 (tetrachloromethane, Cl2C = CCl2 (perchloroethylene, PCE, CH3CCl3 (methyl chloroform, MCF, and CFC-12. Comparisons were done with the data from TRACE-P and ALE/GAGE/AGAGE experiments, we found that the large variability in mixing ratios (relative standard deviation ranged from 9.31 % to 96.55 % of the halocarbons suggested substantial local emissions from the PRD region in 2004. Correlations between the mixing ratio of each species and carbon monoxide (CO was examined, and then the emission of each halocarbon was quantified based on scaling the optimized CO emission inventory with the slope of the regression line fitted to each species relative to CO. The calculated results revealed that mass of CH2Cl2 (7.0 Gg, CH3CCl3 (6.7 Gg, and Cl2C = CCl2 (2.3 Gg accounted for about 62.9 % of total halocarbon emissions, it suggested a significant contribution from solvent use in the PRD region. Emissions of HCFC-22 (3.5 Gg, an alternative refrigerant to chlorofluorocarbons (CFCs, were about 2.3 times greater than those of CFC-12 (1.6 Gg. CFC-12 and HCFC-22 accounted for 21.5 % of total emissions of halocarbons, so that the refrigerant would be the second largest source of halocarbons. However, the ratio approach found only minor emissions of CFCs, such as CFC-11, and the emission of CFC-114 and CFC-113 were close to zero. Emissions of other anthropogenic halocarbons, such as CCl

  6. Mantle electrical conductivity profile of Niger delta region

    Indian Academy of Sciences (India)

    Daniel N Obiora; Francisca N Okeke; K Yumoto; Stan O Agha

    2014-06-01

    The mantle electrical conductivity-depth profile of the Niger delta region in Nigeria has been determined using solar quiet day ionospheric current (Sq).The magnetometer data obtained in 2010 from geomagnetic stations installed in Lagos by magnetic dataset (MAGDAS) in 2008 and data from magnetometers installed in some parts of Niger delta by Center for Basic Space Science, University of Nigeria, Nsukka, were employed in this study. Gauss spherical harmonic analysis (SHA) method was used to separate the internal and external field contributions to Sq current system. The result depicted that the conductivity profile rose steadily from about 0.032 S/m at a depth of 89 km to 0.041 S/m at 100 km and 0.09 S/m at 221 km. This high conductivity region agreed with the global seismic low velocity region, the asthenosphere. The conductivity profile continued increasing downward until it got to 0.157 S/m at a depth of about 373 km (close to the base of upper mantle), 0.201 S/m at 784 km and reached 0.243 S/m at a depth of 1179 km at the lower mantle.

  7. Oxidative capacity and radical chemistry in the polluted atmosphere of Hong Kong and Pearl River Delta region: analysis of a severe photochemical smog episode

    Science.gov (United States)

    Xue, Likun; Gu, Rongrong; Wang, Tao; Wang, Xinfeng; Saunders, Sandra; Blake, Donald; Louie, Peter K. K.; Luk, Connie W. Y.; Simpson, Isobel; Xu, Zheng; Wang, Zhe; Gao, Yuan; Lee, Shuncheng; Mellouki, Abdelwahid; Wang, Wenxing

    2016-08-01

    We analyze a photochemical smog episode to understand the oxidative capacity and radical chemistry of the polluted atmosphere in Hong Kong and the Pearl River Delta (PRD) region. A photochemical box model based on the Master Chemical Mechanism (MCM v3.2) is constrained by an intensive set of field observations to elucidate the budgets of ROx (ROx = OH+HO2+RO2) and NO3 radicals. Highly abundant radical precursors (i.e. O3, HONO and carbonyls), nitrogen oxides (NOx) and volatile organic compounds (VOCs) facilitate strong production and efficient recycling of ROx radicals. The OH reactivity is dominated by oxygenated VOCs (OVOCs), followed by aromatics, alkenes and alkanes. Photolysis of OVOCs (except for formaldehyde) is the dominant primary source of ROx with average daytime contributions of 34-47 %. HONO photolysis is the largest contributor to OH and the second-most significant source (19-22 %) of ROx. Other considerable ROx sources include O3 photolysis (11-20 %), formaldehyde photolysis (10-16 %), and ozonolysis reactions of unsaturated VOCs (3.9-6.2 %). In one case when solar irradiation was attenuated, possibly by the high aerosol loadings, NO3 became an important oxidant and the NO3-initiated VOC oxidation presented another significant ROx source (6.2 %) even during daytime. This study suggests the possible impacts of daytime NO3 chemistry in the polluted atmospheres under conditions with the co-existence of abundant O3, NO2, VOCs and aerosols, and also provides new insights into the radical chemistry that essentially drives the formation of photochemical smog in the high-NOx environment of Hong Kong and the PRD region.

  8. Catalyzing action towards the sustainability of deltas: deltas as integrated socio-ecological systems and sentinels of regional and global change

    Science.gov (United States)

    Foufoula-Georgiou, E.; Tessler, Z. D.; Brondizio, E.; Overeem, I.; Renaud, F.; Sebesvari, Z.; Nicholls, R. J.; Anthony, E.

    2016-12-01

    Deltas are highly dynamic and productive environments: they are food baskets of the world, home to biodiverse and rich ecosystems, and they play a central role in food and water security. However, they are becoming increasingly vulnerable to risks arising from human activities, land subsidence, regional water management, global sea-level rise, and climate extremes. Our Belmont Forum DELTAS project (BF-DELTAS: Catalyzing actions towards delta sustainability) encompasses an international network of interdisciplinary research collaborators with focal areas in the Mekong, Ganges Brahmaputra, and the Amazon deltas. The project is organized around five main modules: (1) developing an analytical framework for assessing delta vulnerability and scenarios of change (Delta-SRES), (2) developing an open-acess, science-based integrative modeling framework for risk assessment and decision support (Delta-RADS), (3) developing tools to support quantitative mapping of the bio-physical and socio-economic environments of deltas and consolidate bio-physical and social data within shared data repositories (Delta-DAT), (4) developing Global Delta Vulnerability Indices (Delta-GDVI) that capture current and projected scenarios for major deltas around the world , and (5) collaborating with regional stakeholders to put the science, modeling, and data into action (Delta-ACT). In this talk, a research summary will be presented on three research domains around which significant collaborative work was developed: advancing biophysical classification of deltas, understanding deltas as coupled socio-ecological systems, and analyzing and informing social and environmental vulnerabilities in delta regions.

  9. Polycyclic aromatic hydrocarbons in upstream riverine runoff of the Pearl River Delta, China: an assessment of regional input sources.

    Science.gov (United States)

    Zhang, Kai; Liang, Bo; Wang, Ji-Zhong; Guan, Yu-Feng; Zeng, Eddy Y

    2012-08-01

    Water samples collected from upstream tributaries of the Pearl River Delta (PRD) and from locations within the PRD (South China) were analyzed for 27 polycyclic aromatic hydrocarbons (PAHs). Average concentrations (aqueous plus particulate) of total 27 PAHs (Σ(27)PAH), 16 priority PAHs designated by the United States Environmental Protection Agency (USEPA) except naphthalene (Σ(15)PAH), and the seven carcinogenic PAHs (Σ(7)PAH) classified by the USEPA were 260 ± 410, 130 ± 310, and 15 ± 12 ng/L, respectively. Riverine PAHs were predominantly generated from coal and vegetation combustion, coke production, vehicle exhausts, and petroleum residues, accounting for 28%, 25%, 22% and 21%, respectively, on average. Upstream riverine fluxes of Σ(27)PAH and Σ(15)PAH amounted to 38.9 and 12.9 tons/year, respectively. The net contributions of Σ(27)PAH and Σ(15)PAH from sources within the PRD were estimated at 21.4 and 21.0 tons/year, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Hydrology and morphology of two river mouth regions (temperate Vistula Delta and subtropical Red River Delta

    Directory of Open Access Journals (Sweden)

    Zbigniew Pruszak

    2005-09-01

    Full Text Available The paper presents a comparative analysis of two different river mouths from two different geographical zones (subtropical and temperate climatic regions. One is the multi-branch and multi-spit mouth of the Red River on the Gulf of Tonkin (Vietnam, the other is the smaller delta of the river Vistula on a bay of the Baltic Sea (Poland. The analysis focuses on the similarities and differences in the hydrodynamics between these estuaries and the adjacent coastal zones, the features of sediment transport, and the long-term morphodynamics of the river outlets. Salinity and water level are also discussed, the latter also in the context of the anticipated global effect of accelerated sea level rise. The analysis shows that the climatic and environmental conditions associated with geographical zones give rise to fundamental differences in the generation and dynamic evolution of the river mouths.

  11. 40 CFR 81.122 - Mississippi Delta Intrastate Air Quality Control Region.

    Science.gov (United States)

    2010-07-01

    ... Quality Control Region. 81.122 Section 81.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Air Quality Control Regions § 81.122 Mississippi Delta Intrastate Air Quality Control Region. The Mississippi Delta Intrastate Air Quality Control Region consists of the territorial area encompassed by...

  12. Aromatic hydrocarbons as ozone precursors before and after outbreak of the 2008 financial crisis in the Pearl River Delta region, south China

    Science.gov (United States)

    Zhang, Yanli; Wang, Xinming; Blake, Donald R.; Li, Longfeng; Zhang, Zhou; Wang, Shaoyi; Guo, Hai; Lee, Frank S. C.; Gao, Bo; Chan, Loyin; Wu, Dui; Rowland, F. Sherwood

    2012-08-01

    In the second half of 2008 China's highly industrialized Pearl River Delta (PRD) region was hard-hit by the financial crisis (FC). This study reports volatile organic compounds measured in the PRD during November-December in both 2007 before the FC and 2008 after the FC. While total mixing ratios of non-methane hydrocarbons (NMHCs) on average were only about 7% lower from 40.2 ppbv in 2007 to 37.5 ppbv in 2008, their ozone formation potentials (OFPs) dropped about 30%, resulting from about 55% plummet of aromatic hydrocarbons (AHs) against a greater than 20% increase of total alkanes/alkenes. The elevated alkanes and alkenes in 2008 could be explained by greater emissions from vehicle exhausts and LPG combustion due to rapid increase of vehicle numbers and LPG consumption; the drop of AHs could be explained by reduced emissions from industries using AH-containing solvents due to the influence of the FC, as indicated by much lower ratios of toluene to benzene and of xylenes/trichloroethylene/tetrachloroethylene to carbon monoxide (CO) in 2008. Source apportionment by positive matrix factorization (PMF) also revealed much less contribution of industry solvents to total anthropogenic NMHCs and particularly to toluene and xylenes in 2008 than in 2007. Based on PMF reconstructed source contributions, calculated OFPs by industrial emissions were responsible for 40.8% in 2007 in contrast to 18.4% in 2008. Further investigation into local industry output statistics suggested that the plummet of AHs in 2008 should be attributed to small enterprises, which contributed largely to ambient AHs due to their huge numbers and non-existent emission treatment, but were much more influenced by the FC.

  13. Reflections on Development Strategy of Pearl River Delta: In Comparison with Yangtze River Delta

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>1. A comparison between Pearl River Delta and Yangtze River Delta 1.1 Basic conditions 1.1.1 Location, area and scope Located in the southeast of Guangdong Province, the Pearl River Delta (PRD) as an economic zone is a compound delta

  14. Investigation of polycyclic aromatic hydrocarbon level in blood and semen quality for residents in Pearl River Delta Region in China.

    Science.gov (United States)

    Song, Xiao Fei; Chen, Zhi Yuan; Zang, Zhi Jun; Zhang, Ya Nan; Zeng, Feng; Peng, Yen Ping; Yang, Chen

    2013-10-01

    This study is the first one investigating the correlation between the concentration of polycyclic aromatic hydrocarbon (PAHs) in blood and semen qualities for residents in the Pearl River Delta (PRD) region in China. Blood samples from 53 infertile volunteers were studied for measures of semen quality and 16 PAHs. Information on the study subjects' living habits (such as smoking, drinking and preference of consumption for food) and general information (age, body-mass-index (BMI) and educational background) were also collected. Statistical results showed that age and BMI were significantly and negatively related to semen motilities. The total concentrations of PAHs (∑16 PAHs) in the blood were 12,010, 7493, 9105 and 8647ng/g for factory workers, office workers, technicians and salespersons, respectively. In addition, ∑16 PAHs in the blood of smokers, drinkers and heavy-taste food consumers were 11,950, 11,266 and 12,141ng/g, which were higher than those observed in nonsmokers (10,457ng/g), nondrinkers (10,920ng/g) and light-taste food consumers (9202ng/g), individually. Furthermore, the Pearson correlation analysis results showed significant positive correlations between BMI and ∑16 PAHs in the blood. Statistically significant correlations were observed between semen motilities and ∑16 PAHs in the blood as well. Logistic regression results showed that for each 1ng/g increase in ∑16 PAHs in blood samples, the log odds of experiencing a pregnancy decrease by 0.039 on average. However, more evidences are needed to clarify the impact of PAHs in the blood to male infertility.

  15. Impacts of aerosols on weather and regional climate over the Pearl River Delta megacity area in China

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2011-08-01

    Full Text Available Seven-year measurements of precipitation, lightning flashes, and visibility from 2000 to 2006 have been analyzed in the Pearl River Delta (PRD region, China, with a focus on the Guangzhou megacity area. Statistical analysis shows that the occurrence of heavy rainfall (>25 mm per day and frequency of lightning strikes are reversely correlated to visibility during this period. To elucidate the effects of aerosols on cloud processes, precipitation, and lightning activity, a cloud resolving – Weather Research and Forecasting (CR-WRF model with a two-moment bulk microphysical scheme is employed to simulate a mesoscale convective system occurring on 28 Match 2009 in the Guangzhou megacity area. The model predicted evolutions of composite radar reflectivity and accumulated precipitation are in agreement with measurements from S-band weather radars and automatic gauge stations. The calculated lightning potential index (LPI exhibits temporal and spatial consistence with lightning flashes recorded by a local lightning detection network. Sensitivity experiments have been performed to reflect aerosol conditions representative of polluted and clean cases. The simulations suggest that precipitation and LPI are enhanced by about 16 % and 50 %, respectively, under the polluted aerosol condition. Our results suggest that elevated aerosol loading suppresses light and moderate precipitation (less than 25 mm per day, but enhances heavy precipitation. The responses of hydrometeors and latent heat release to different aerosol loadings reveal the physical mechanism for the precipitation and lightning enhancement in the Guangzhou megacity area, showing more efficient mixed phase processes and intensified convection under the polluted aerosol condition.

  16. Simulation of regional land subsidence in the southern Yangtze Delta

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Investigation of the deformation characteristics of individual hydrostratigraphic units is the key to construct a regional land subsidence model. All of 12 hydrostratigraphic units in the study area were discussed throughout. On the basis of the measured data of groundwater level, five kinds of changing patterns of groundwater level were deduced and the relationship between the deformation characteris-tics of aquifer units and the corresponding changing patterns of groundwater level was discussed. The study area is 1.7×104 km2, where the geological condition is complex. The changing patterns of groundwater level the hydrostratigraphic units have experienced vary from site to site and from time to time. Consequently, the deformation characteristics of units are sophisticated. An identical hydros-tratigraphic unit may exhibit different deformation characteristics, such as elasticity, elasto-plasticity, visco-elasticity, and visco-elasto-plasticity, at different sites or during different periods, not to mention the different units. The existing models are difficult to describe the complex visco-elasto-plastic con-stitutive law under the condition of land subsidence. So the Merchant’s model was modified to depict the visco-elasto-plastic behavior of units. Then a three-dimensional flow model with variable parame-ters and a vertical one-dimensional subsidence model were constructed and coupled. The coupled model was applied in simulating land subsidence in the southern Yangtze Delta and a satisfactory re-sult was obtained. The simulation results show that the new coupled model can depict the complex geological conditions and describe the developing process of land subsidence very well in the south-ern Yangtze Delta. The new model can surely be used to predict land subsidence in the future, which is very helpful to taking measurements to control land subsidence.

  17. Development of PM2.5 and NO2 models in a LUR framework incorporating satellite remote sensing and air quality model data in Pearl River Delta region, China.

    Science.gov (United States)

    Yang, Xiaofan; Zheng, Yixuan; Geng, Guannan; Liu, Huan; Man, Hanyang; Lv, Zhaofeng; He, Kebin; de Hoogh, Kees

    2017-07-01

    High resolution pollution maps are critical to understand the exposure and health effect of local residents to air pollution. Currently, none of the single technologies used to measure or estimate concentrations of pollutants can provide sufficient resolved exposure data. Land use regression (LUR) models were developed to combine ground-based measurements, satellite remote sensing (SRS) and air quality model (AQM), together with geographic and local source related spatial inputs, to generate high resolution pollution maps for both PM2.5 and NO2 in Pearl River Delta (PRD), China. Four sets of LUR models (LUR without SRS or AQM, with SRS only, with AQM only, and with both SRS and AQM), all including local traffic emissions and land use variables, were compared to evaluate the contribution of SRS and AQM data to the performance of LUR models in PRD region. For NO2, the annual model with SRS estimate performed best, explaining 60.5% of the spatial variation. For PM2.5, the annual model with traditional predictor variables without SRS or AQM estimates showed the best performance, explaining 88.4% of the spatial variation. Pollution surfaces at 200 m*200 m resolution were generated according to the best performed models. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Modeling of HCHO and CHOCHO at a semi-rural site in southern China during the PRIDE-PRD2006 campaign

    Science.gov (United States)

    Li, X.; Rohrer, F.; Brauers, T.; Hofzumahaus, A.; Lu, K.; Shao, M.; Zhang, Y. H.; Wahner, A.

    2014-11-01

    HCHO and CHOCHO are important trace gases in the atmosphere, serving as tracers of VOC oxidations. In the past decade, high concentrations of HCHO and CHOCHO have been observed for the Pearl River Delta (PRD) region in southern China. In this study, we performed box model simulations of HCHO and CHOCHO at a semi-rural site in the PRD, focusing on understanding their sources and sinks and factors influencing the CHOCHO to HCHO ratio (RGF). The model was constrained by the simultaneous measurements of trace gases and radicals. Isoprene oxidation by OH radicals is the major pathway forming HCHO, followed by degradations of alkenes, aromatics, and alkanes. The production of CHOCHO is dominated by isoprene and aromatic degradation; contributions from other NMHCs are of minor importance. Compared to the measurement results, the model predicts significant higher HCHO and CHOCHO concentrations. Sensitivity studies suggest that fresh emissions of precursor VOCs, uptake of HCHO and CHOCHO by aerosols, fast vertical transport, and uncertainties in the treatment of dry deposition all have the potential to contribute significantly to this discrepancy. Our study indicates that, in addition to chemical considerations (i.e., VOC composition, OH and NOx levels), atmospheric physical processes (e.g., transport, dilution, deposition) make it difficult to use the CHOCHO to HCHO ratio as an indicator for the origin of air mass composition.

  19. Variation of particle number size distributions and chemical compositions at the urban and downwind regional sites in the Pearl River Delta during summertime pollution episodes

    Directory of Open Access Journals (Sweden)

    D. L. Yue

    2010-06-01

    Full Text Available In order to characterize the features of particulate pollution in the Pearl River Delta (PRD in the summer, continuous measurements of particle number size distributions and chemical compositions were simultaneously performed at Guangzhou urban site (GZ and Back-garden downwind regional site (BG in July 2006. Particle number concentration from 20 nm to 10 μm at BG was (1.7±0.8×104 cm−3, about 40% lower than that at GZ, (2.9±1.1×104 cm−3 with intensive traffic emissions. The total particle volume concentration at BG was 94±34 μm3 cm−3, similar to that at GZ, 96±43 μm3 cm−3. More 20–100 nm particles, significantly affected by the traffic emissions, were observed at GZ, while 100–660 nm particle number concentrations were similar at both sites as they are more regional. PM2.5 values were also similar at GZ (69±43 μg m−3 and BG (69±58 μg m−3, indicating the fine particulate pollution in the PRD region to be regional. Two kinds of pollution episodes, the accumulation pollution episode and the regional transport pollution episode, were observed. Fine particles over 100 nm dominated both number and volume concentrations of total particles during the late periods of these pollution episodes. Accumulation and secondary transformations are two main reasons for the nighttime accumulation pollution episode. SO4−2, NO3, and NH4+ accounted for about 60% in 100–660 nm particle mass and PM2.5. When south or south-southeast wind prevailed in the PRD region, regional transport of pollutants takes place. Regional transport contributed about 30% to fine particulate pollution at BG during a regional transport case. Secondary transformation played an important role during regional transport, causing higher increase rates of secondary

  20. Variation of particle number size distributions and chemical compositions at the urban and downwind regional sites in the Pearl River Delta during summertime pollution episodes

    Directory of Open Access Journals (Sweden)

    D. L. Yue

    2010-10-01

    Full Text Available In order to characterize the features of particulate pollution in the Pearl River Delta (PRD in the summer, continuous measurements of particle number size distributions and chemical compositions were simultaneously performed at Guangzhou urban site (GZ and Back-garden downwind regional site (BG in July 2006. Particle number concentration from 20 nm to 10 μm at BG was (1.7±0.8×104 cm−3, about 40% lower than that at GZ, (2.9±1.1×104 cm−3. The total particle volume concentration at BG was 94±34 μm3 cm−3, similar to that at GZ, 96±43 μm3 cm−3. More 20–100 nm particles, significantly affected by the traffic emissions, were observed at GZ, while 100–660 nm particle number concentrations were similar at both sites as they are more regional. PM2.5 values were similar at GZ (69±43 μg m−3 and BG (69±58 μg m−3 with R2 of 0.71 for the daily average PM2.5 at these two sites, indicating the fine particulate pollution in the PRD region to be regional. Two kinds of pollution episodes, the accumulation pollution episode and the regional transport pollution episode, were observed. Fine particles over 100 nm dominated both number and volume concentrations of total particles during the late periods of these pollution episodes. Accumulation and secondary transformation are the main reasons for the nighttime accumulation pollution episode. SO42−, NO3 accounted for about 60% in 100–660 nm particle mass and PM2.5 increase. When south or southeast wind prevailed in the PRD region, regional transport of pollutants took place. Regional transport contributed about 30% to fine particulate pollution at BG during a regional transport case. Secondary transformation played an important role during regional transport, causing higher increase

  1. Monitoring rice farming activities in the Mekong Delta region

    Science.gov (United States)

    Nguyen, S. T.; Chen, C. F.; Chen, C. R.; Chiang, S. H.; Chang, L. Y.; Khin, L. V.

    2015-12-01

    Half of the world's population depends on rice for survival. Rice agriculture thus plays an important role in the developing world's economy. Vietnam is one of the largest rice producers and suppliers on earth and more than 80% of the exported rice was produced from the Mekong Delta region, which is situated in the southwestern Vietnam and encompasses approximately 40,000 km2. Changes in climate conditions could likely trigger the increase of insect populations and rice diseases, causing the potential loss of rice yields. Monitoring rice-farming activities through crop phenology detection can provide policymakers with timely strategies to mitigate possible impacts on the potential yield as well as rice grain exports to ensure food security for the region. The main objective of this study is to develop a logistic-based algorithm to investigate rice sowing and harvesting activities from the multi-temporal Moderate Resolution Imaging Spectroradiometer (MODIS)-Landsat fusion data. We processed the data for two main cropping seasons (i.e., winter-spring and summer-autumn seasons) through a three-step procedure: (1) MODIS-Landsat data fusion, (2) construction of the time-series enhanced vegetation index 2 (EVI2) data, (3) rice crop phenology detection. The EVI2 data derived from the fusion results between MODIS and Landsat data were compared with that of Landsat data indicated close correlation between the two datasets (R2 = 0.93). The time-series EVI2 data were processed using the double logistic method to detect the progress of sowing and harvesting activities in the region. The comparisons between the estimated sowing and harvesting dates and the field survey data revealed the root mean squared error (RMSE) values of 8.4 and 5.5 days for the winter-spring crop and 9.4 and 12.8 days for the summer-autumn crop, respectively. This study demonstrates the effectiveness of the double logistic-based algorithm for rice crop monitoring from temporal MODIS-Landsat fusion data

  2. Regional pole assignment for uncertain delta-operator systems

    Institute of Scientific and Technical Information of China (English)

    Man LIU; Yuanwei JING; Siying ZHANG

    2004-01-01

    The pole assignment in a specified disk by state feedback for uncertain delta-operator systems is studied.By making use of algebra Riccati equations,a sufficient and necessary condition of pole assignment for a kind of parameter uncertain delta-operator system in a specified disk by state feedback is presented.And the design method of state feedback controller is also developed.The proposed method can unify some previous related results of continuous and discrete time systems into the delta framework.The efficiency of the design method is illustrated by a numerical example.

  3. Overweight and obesity profiles in Niger Delta Region, Nigeria

    Directory of Open Access Journals (Sweden)

    Alphhonsus U. Idung

    2014-01-01

    Full Text Available Introduction: Overweight and obesity are global public health problems because of their effect on individuals, families and communities. The objective of this study was to describe the profile of overweight and obesity amongst adult out patients in Uyo in the Niger Delta region of Nigeria.Method: This was a cross-sectional descriptive study done between October 2011 and March 2012. Using a systematic sampling technique, 584 subjects aged 18–65 years were recruited; data were collected with a structured questionnaire. Subjects were measured for height, weight, waist and hip circumferences. Body mass index (BMI and waist–hip ratio (WHR were calculated. Subjects with a BMI of 25.0 kg/m2 – 29.9 kg/m2 were regarded as being overweight whilst a BMI of > 30.0 kg/m2 was regarded as obese. Subjects with a WHR of > 0.90 for men or > 0.85 for women were regarded as having abnormal WHR.Results: Of the 584 subjects, 196 (36.6% were men and 388 (66.4% women. The mean age for men and women was 43.3 ± 17.8 years and 50.2 ± 13.6 years, respectively. The prevalence of overweight amongst men was 39.8% versus 31.7% for women; obesity in men was 28.0% versus 52.0% in women. Overweight and obesity were more prevalent in subjects aged 25–54 years and amongst married subjects. There was a significant relationship between obesity and television viewing (p = 0.003. Hypertension (p = 0.008 and osteoarthropathies (p = 0.043 were more prevalent amongst the obese than the non-obese subjects.Conclusion: Overweight and obesity are now common in our environment. There is therefore a need for more public education about the health consequences of big body size.

  4. Chloride as tracer of solute transport in the aquifer-aquitard system in the Pearl River Delta, China

    Science.gov (United States)

    Kuang, Xingxing; Jiao, Jiu Jimmy; Wang, Ya

    2016-08-01

    A 1D numerical model is constructed to investigate the impact of sedimentation and sea level changes on transport of Cl- in the aquifer-aquitard system in the Pearl River Delta (PRD), China. The model simulates the evolution of the vertical Cl- concentration profiles during the Holocene. Sedimentation is modeled as a moving boundary problem. Chloride concentration profiles are reconstructed for nine boreholes, covering a wide area of the PRD, from northwest to southeast. Satisfactory agreement is obtained between simulated and measured Cl- concentration profiles. Diffusion solely is adequate to reproduce the vertical Cl- concentration profiles, which indicates that diffusion is the regionally dominant vertical transport mechanism across the aquitards in the PRD. The estimated effective diffusion coefficients of the aquitards range from 2.0 × 10-11 to 2.0 × 10-10 m2/s. The effective diffusion coefficients of the aquifers range from 3.0 × 10-11 to 4.0 × 10-10 m2/s. Advective transport tends to underestimate Cl- concentrations in the aquitard and overestimate Cl- concentrations in the basal aquifer. The results of this study will help understand the mechanisms of solute transport in the PRD and other deltas with similar geological and hydrogeological characteristics.

  5. Comparison of aerosol hygroscopicity and mixing state between winter and summer seasons in Pearl River Delta region, China

    Science.gov (United States)

    Jiang, Rongxin; Tan, Haobo; Tang, Lili; Cai, Mingfu; Yin, Yan; Li, Fei; Liu, Li; Xu, Hanbing; Chan, P. W.; Deng, Xuejiao; Wu, Dui

    2016-03-01

    environment. Hence, only assuming a constant mixing state of soot particles, such as pure external or internal for the regional climate model and air quality model is still not realistic and may lead to uncertainties for the Pearl River Delta (PRD) region which is one of the three major economic regions in China. Comparing the diurnal variation of NFNH in both seasons, it seems that such a diurnal cycle was mainly related to the differences in evolution of mixing layer between two seasons. Such quantitative hygroscopic properties of sub-micro particles are essential in assessing their impact on weather-climate effect and atmospheric visibility.

  6. Building a competitive Pearl River Delta region: cooperation, coordination, and planning

    OpenAIRE

    2002-01-01

    Papers mainly originated from the Seminar on Building a Competitive Pearl River Delta Region: Cooperation, Coordination and planning held on 8 July 2000 at the Hong Kong Convention and Exhibition Centre

  7. Challenges, Approaches and Experiences from Asian Deltas and the Rhine-Meuse Delta : Regional Training Workshop on Delta Planning and Management

    NARCIS (Netherlands)

    Wosten, J.H.M.; Douven, W.; Long Phi, H.; Fida Abdullah Khan, M.

    2013-01-01

    River delta's, like the Mekong Delta (Vietnam), Ganges-Brahmaputra Delta (Bangladesh), Ayeyarwady Delta (Myanmar), Nile (Egypt) and Ciliwung Delta (Indonesia) are developing rapidly and are characterised by large-scale urbanisation and industrialization processes. They are facing serious planning ch

  8. Humpback Dolphins in Hong Kong and the Pearl River Delta: Status, Threats and Conservation Challenges.

    Science.gov (United States)

    Karczmarski, Leszek; Huang, Shiang-Lin; Or, Carmen K M; Gui, Duan; Chan, Stephen C Y; Lin, Wenzhi; Porter, Lindsay; Wong, Wai-Ho; Zheng, Ruiqiang; Ho, Yuen-Wa; Chui, Scott Y S; Tiongson, Angelico Jose C; Mo, Yaqian; Chang, Wei-Lun; Kwok, John H W; Tang, Ricky W K; Lee, Andy T L; Yiu, Sze-Wing; Keith, Mark; Gailey, Glenn; Wu, Yuping

    2016-01-01

    In coastal waters of the Pearl River Delta (PRD) region, the Indo-Pacific humpback dolphin (Sousa chinensis) is thought to number approximately 2500 individuals. Given these figures, the putative PRD population may appear strong enough to resist demographic stochasticity and environmental pressures. However, living in close proximity to the world's busiest seaport/airport and several densely populated urban centres with major coastal infrastructural developments comes with challenges to the long-term survival of these animals. There are few other small cetacean populations that face the range and intensity of human-induced pressures as those present in the PRD and current protection measures are severely inadequate. Recent mark-recapture analyses of the animals in Hong Kong waters indicate that in the past two decades the population parameters have not been well understood, and spatial analyses show that only a very small proportion of the dolphins' key habitats are given any form of protection. All current marine protected areas within the PRD fail to meet a minimum habitat requirement that could facilitate the population's long-term persistence. Demographic models indicate a continuous decline of 2.5% per annum, a rate at which the population is likely to drop below the demographic threshold within two generations and lose 74% of the current numbers within the lifespan of three generations. In Hong Kong, the case of humpback dolphins represents a particularly explicit example of inadequate management where a complete revision of the fundamental approach to conservation management is urgently needed.

  9. Observation of nighttime nitrous acid (HONO) formation at a non-urban site during PRIDE-PRD2004 in China

    Science.gov (United States)

    Su, Hang; Cheng, Ya Fang; Cheng, Peng; Zhang, Yuan Hang; Dong, Shuofei; Zeng, Li Min; Wang, Xuesong; Slanina, Jacob; Shao, Min; Wiedensohler, Alfred

    Though the importance of HONO as an OH precursor has been recognized for years, its chemical formation pathway is still not well understood. This inhibited the simulations of HONO and observation-based formation rates provided an alternative for the air quality models. However, HONO formation rate derived from certain period may be significantly influenced by uncertainties in transport and emission processes. In this study the use of large sample and scaling methods were recommended in the calculation of HONO formation rate. During the Program of Regional Integrated Experiments of Air Quality over Pear River Delta (PRIDE-PRD2004), good correlations between HONO and NO2 were found supporting the involvement of NO2 in HONO formation. An average NO2-to-HONO nighttime conversion rate CHONO of 1.6%h-1 was derived at a non-urban site Xinken. This conversion rate was comparable to other field measurements and could not be explained by gas phase reactions only. If assumed that HONO was formed only on the ground surface, the observed conversion rate could be explained by the reactions of NO2 on ground surfaces only if three deposited NO2 lead to one HONO released. The emission factor of HONO and its sampling interferences during the measurements were also evaluated in this article.

  10. New particle formation in the presence of a strong biomass burning episode at a downwind rural site in PRD, China

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Z. B.; Hu, M.; Yue, D. L.; Yang, Q.; Zhang, Y. H. [State Key Joint Lab. of Environmental Simulation and Pollution Control, Coll. of Environmental Sciences and Engineering, Peking Univ., Beijing (China)], e-mail: minhu@pku.edu.cn; He, L. Y.; Huang, X. F. [Key Lab. for Urban Habitat Environmental Science and Technology, School of Environment and Energy, Peking Univ. Shenzhen Graduate School, Shenzhen (China); Zheng, J. [Dept. of Atmospheric Science, Texas AandM Univ., College Station, Texas (United States); Zhang, R. Y. [State Key Joint Lab. of Environmental Simulation and Pollution Control, Coll. of Environmental Sciences and Engineering, Peking Univ., Beijing (China); Department of Atmospheric Science, Texas AandM Univ., College Station, Texas (United States))

    2013-09-15

    In order to characterise the features of particle pollution in the Pearl River Delta (PRD) region, a 1-month intensive campaign was conducted at the rural supersite (Kaiping) in the autumn of 2008. In total, 12 new particle formation (NPF) events are identified out of 30 campaign days. The results show that in the case of higher source and sink values, the result of the competition between source and sink is more likely the key limiting factor to determine the observation of NPF events at Kaiping. One episode with consecutive NPF events in the presence of strong biomass burning plume was observed between 10 and 15 November. The elevation of particle volume concentration (6.1 mm{sup 3}/cm{sup 3}/day) is due to the coaction by the local biomass burning and secondary transformation. Organics and sulphates are the major components in PM{sub 1}, accounting for 42% and 35% of the mass concentration, respectively. In this study, a rough estimation is applied to quantify the contributions of diverse sources to the particle number concentration. On average, the primary emission and secondary formation provide 28 and 72% of particle number concentration and 21% and 79% of mass concentration, respectively.

  11. HULIS in emissions of fresh rice straw burning and in ambient aerosols in the pearl river delta region, China

    Directory of Open Access Journals (Sweden)

    P. Lin

    2010-03-01

    Full Text Available HUmic-LIke Substances (HULIS are an abundant unresolved mixture of organic compounds present in atmospheric samples. Biomass burning (BB has been recognized as an important primary source of HULIS, but measurements of HULIS in various fresh BB particles are lacking. In this work, HULIS in emissions of rice straw burning in a number of field and chamber experiments was measured. The HULIS/OC ratio was 0.34±0.05 in μg/μgC, showing small variance among emissions under different burning conditions. The influence of BB on ambient HULIS levels was investigated by examining the spatial and temporal variation of HULIS and other aerosol constituents and interspecies relations in ambient PM2.5 collected at an urban and a suburban location in the Pearl River Delta (PRD, China over a period of one year. The HULIS concentrations in the ambient PM2.5 were significantly higher in air masses originating from regions influenced by BB. Significant correlations between HULIS and water-soluble K+ concentrations at both sites further support that BB was an important source of HULIS. HULIS also correlated well with sulfate, oxalate, and oxidant (the sum of O3 and NO2. The HULIS/OC ratios in BB-influenced ambient aerosols (~0.6 were much higher than those in the fresh BB emissions (0.34, implying that secondary formation was also an important source of HULIS in the atmosphere. The annual average HULIS concentrations were 4.9 μg m−3 at the urban site and 7.1 μg m−3 at the suburban site while the annual average concentrations of elemental carbon were 3.3 μg m−3 and 2.4 μg m−3, respectively. The urban-suburban spatial gradient of HULIS was opposite to that of elemental carbon, negating vehicular emissions as a significant source of HULIS.

  12. Characterizing ionic species in PM2.5 and PM10 in four Pearl River Delta cities, South China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    PM2.5 and PM10 samples were collected at four major cities in the Pearl River Delta (PRD), South China, during winter and summer in 2002. Six water-soluble ions, Na+, NH4+, K+, Cl-, NO3- and SO42- were measured using ion chromatography. On average, ionic species accounted for 53.3% and 40.5% for PM2.5 and PM10, respectively in winter and 39.4% and 35.2%, respectively in summer. Secondary ions such as sulfate, nitrate and ammonium accounted for the major part of the total ionic species. Sulfate was the most abundant specie followed by nitrate. Overall, a regional pollution tendency were shown in this campaign though there were higher concentrations of sulfate, nitrate and ammonium measured in Guangzhou City than those in the other PRD cities. Significant seasonal variations were also observed with higher levels of species in winter and lower in summer. The Asian monsoon system was favorable for removal and diffusion of air pollutants in PRD in summer while highly loading of local industrial emissions tended to deteriorate the air quality as well. NO3-/SO42- ratio indicates that mobile sources have considerably contribution to the urban aerosol but stationary sources should still not be neglected. Besides the primary emissions, complex atmospheric reactions under favorable weather conditions should be paid more attention for formulating control strategies for primary emission in the future in the PRD region.

  13. Radar-observed diurnal cycle and propagation of convection over the Pearl River Delta during Mei-Yu season

    Science.gov (United States)

    Chen, Xingchao; Zhao, Kun; Xue, Ming; Zhou, Bowen; Huang, Xuanxuan; Xu, Weixin

    2015-12-01

    Using operational Doppler radar and regional reanalysis data from 2007-2009, the climatology and physical mechanisms of the diurnal cycle and propagation of convection over the Pearl River Delta (PRD) region of China during the Mei-Yu seasons are investigated. Analyses reveal two hot spots for convection: one along the south coastline of PRD and the other on the windward slope of mountains in the northeastern part of PRD. Overall, convection occurs most frequently during the afternoon over PRD due to solar heating. On the windward slope of the mountains, convection occurrence frequency exhibits two daily peaks, with the primary peak in the afternoon and the secondary peak from midnight to early morning. The nighttime peak is shown to be closely related to the nocturnal acceleration and enhanced lifting on the windward slope of southwesterly boundary layer flow, in the form of boundary layer low-level jet. Along the coastline, nighttime convection is induced by the convergence between the prevailing onshore wind and the thermally induced land breeze in the early morning. Convection on the windward slope of the mountainous area is more or less stationary. Convection initiated near the coastline along the land breeze front tends to propagate inland from early morning to early afternoon when land breeze cedes to sea breeze and the prevailing onshore flow.

  14. THE SPATIAL DIVISION OF INDUSTRIES OF THE PEARL RIVER DELTA IN THE 1990s: CHARACTERISTICS AND TRENDS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The article analyzed the spatial division of industries of the Pearl River Delta (PRD) in the 1990s, a period that witnessed the deepening of the reform and opening policies and continued rapid development of the region. By adopting the index of specialization, the extent of specialization, its change and its spatial distribution in the region are measured and demonstrated.The research revealed that, despite the trend of more balanced development of the secondary sector between the PRD and the rest of the province, in the PRD, it is the unbalanced development that dominated and the spatial division of the secondary sector has been shaped. The tertiary industry has also been experiencing unbalance development and the spatial division of the tertiary sector has been emerging, its extent of concentration appearing even more evident than that of the secondary sector. The author also discussed the linkage between the spatial division of the two sectors. In the end of the paper, the trends of the spatial division of the industries in the PRD are forecasted.

  15. Regional and local new particle formation events observed in the Yangtze River Delta region, China

    Science.gov (United States)

    Dai, Liang; Wang, Honglei; Zhou, Luyu; An, Junlin; Tang, Lili; Lu, Chunsong; Yan, Wenlian; Liu, Ruiyang; Kong, Shaofei; Chen, Mindong; Lee, Shanhu; Yu, Huan

    2017-02-01

    To study the spatial inhomogeneity of new particle formation (NPF) in the polluted atmosphere of China, we conducted simultaneous measurements at an urban site near a petrochemical industrial area and a regional background site in the Yangtze River Delta region from September to November 2015. At the urban site we observed a type of local NPF event (number of events: n = 5), in which nucleation was limited to a small area but persisted for 6.8 h on average during the daytime. Formation rates of 5 nm particles (J5) were found to be correlated positively with the H2SO4 proxy (log J5 versus log[H2SO4] slope near 1) in both local and regional events. Furthermore, J5 was enhanced by the anthropogenic volatile organic carbon (VOC) plumes from nearby industrial area in the local events compared to the regional events. Size-dependent aerosol dynamics calculation showed that in comparison with the observed regional events, the local events were featured with high nucleation rate (J1.3 > 1000 cm-3 s-1), high growth rate of sub-3 nm particles (GRsub-3 > 20 nm h-1), and high number concentration of nucleation mode particles (mean peak N5-20: 6 × 104 cm-3). Considering these features, the local NPF events of anthropogenic origin may also be an important contributor to cloud condensation nuclei concentrations in urban and regional scales. In addition, the comparison of simultaneous regional NPF events between the two sites (number of events: n = 7) suggested that regional NPF intensity may be underestimated by the single-point measurement at an urban site, due to the heterogeneity of air masses.

  16. Landscape ecological security assessment based on projection pursuit in Pearl River Delta.

    Science.gov (United States)

    Gao, Yang; Wu, Zhifeng; Lou, Quansheng; Huang, Huamei; Cheng, Jiong; Chen, Zhangli

    2012-04-01

    Regional landscape ecological security is an important issue for ecological security, and has a great influence on national security and social sustainable development. The Pearl River Delta (PRD) in southern China has experienced rapid economic development and intensive human activities in recent years. This study, based on landscape analysis, provides a method to discover the alteration of character among different landscape types and to understand the landscape ecological security status. Based on remotely sensed products of the Landsat 5 TM images in 1990 and the Landsat 7 ETM+ images in 2005, landscape classification maps of nine cities in the PRD were compiled by implementing Remote Sensing and Geographic Information System technology. Several indices, including aggregation, crush index, landscape shape index, Shannon's diversity index, landscape fragile index, and landscape security adjacent index, were applied to analyze spatial-temporal characteristics of landscape patterns in the PRD. A landscape ecological security index based on these outcomes was calculated by projection pursuit using genetic algorithm. The landscape ecological security of nine cities in the PRD was thus evaluated. The main results of this research are listed as follows: (1) from 1990 to 2005, the aggregation index, crush index, landscape shape index, and Shannon's diversity index of nine cities changed little in the PRD, while the landscape fragile index and landscape security adjacent index changed obviously. The landscape fragile index of nine cities showed a decreasing trend; however, the landscape security adjacent index has been increasing; (2) from 1990 to 2005, landscape ecology of the cities of Zhuhai and Huizhou maintained a good security situation. However, there was a relatively low value of ecological security in the cities of Dongguan and Foshan. Except for Foshan and Guangzhou, whose landscape ecological security situation were slightly improved, the cities had reduced

  17. Water Use Conservation Scenarios for the Mississippi Delta Using an Existing Regional Groundwater Flow Model

    Science.gov (United States)

    Barlow, J. R.; Clark, B. R.

    2010-12-01

    The alluvial plain in northwestern Mississippi, locally referred to as the Delta, is a major agricultural area, which contributes significantly to the economy of Mississippi. Land use in this area can be greater than 90 percent agriculture, primarily for growing catfish, corn, cotton, rice, and soybean. Irrigation is needed to smooth out the vagaries of climate and is necessary for the cultivation of rice and for the optimization of corn and soybean. The Mississippi River Valley alluvial (MRVA) aquifer, which underlies the Delta, is the sole source of water for irrigation, and over use of the aquifer has led to water-level declines, particularly in the central region. The Yazoo-Mississippi-Delta Joint Water Management District (YMD), which is responsible for water issues in the 17-county area that makes up the Delta, is directing resources to reduce the use of water through conservation efforts. The U.S. Geological Survey (USGS) recently completed a regional groundwater flow model of the entire Mississippi embayment, including the Mississippi Delta region, to further our understanding of water availability within the embayment system. This model is being used by the USGS to assist YMD in optimizing their conservation efforts by applying various water-use reduction scenarios, either uniformly throughout the Delta, or in focused areas where there have been large groundwater declines in the MRVA aquifer.

  18. Quantification of Multiple Climate Change and Human Activity Impact Factors on Flood Regimes in the Pearl River Delta of China

    Directory of Open Access Journals (Sweden)

    Yihan Tang

    2016-01-01

    Full Text Available Coastal flood regimes have been irreversibly altered by both climate change and human activities. This paper aims to quantify the impacts of multiple factors on delta flood. The Pearl River Delta (PRD, with dense river network and population, is one of the most developed coastal areas in China. The recorded extreme water level (m.s.l. in flood season has been heavily interfered with by varied income flood flow, sea-level rise, and dredged riverbeds. A methodology, composed of a numerical model and the index R, has been developed to quantify the impacts of these driving factors in the the PRD. Results show that the flood level varied 4.29%–53.49% from the change of fluvial discharge, 3.35%–38.73% from riverbed dredging, and 0.12%–16.81% from sea-level rise. The variation of flood flow apparently takes the most effect and sea-level rise the least. In particular, dense river network intensifies the impact of income flood change and sea-level rise. Findings from this study help understand the causes of the the PRD flood regimes and provide theoretical support for flood protection in the delta region.

  19. The Comparative Advantage Analysis of Innovation in the Pearl River Delta Region:From the Institutional Embeddedness Perspective%珠三角创新的比较优势分析--基于制度嵌入性的视角

    Institute of Scientific and Technical Information of China (English)

    丘晴; 丘海雄

    2016-01-01

    珠三角的创新主要是渐进式的创新,具有自下而上、专业化和多样性的特征。通过对珠三角地方政府和企业创新的调查研究,发现珠三角创新的比较优势在于渐进式创新及其所嵌入的优良的制度环境。该区域的渐进式创新并不依赖雄厚的科技资源和研发实力,它嵌入于高度的市场化、集群化、国际化、良好的地方政策体系以及独特的岭南文化等正式和非正式制度环境之中,这些制度相互耦合,促成和限定了创新行为的选择。文章在上述研究的基础上提出了一系列强化珠三角创新比较优势的政策建议。%The innovation mode in the Pearl River Delta ( PRD ) region is mainly incremental innovation, which is characterized by such features as bottom - up, specialization and diversity. Based on the innovation research into local governments and enterprises in the PRD region, the paper finds out that the comparative advantage of innovation in the PRD region lies in the incremental innovation mode as well as the favorable institutional environment in which it is embedded. The incremental innovation in the region does not rely on abundant S&T resources and strong R&D capacity, but rather local formal and informal institutions, including high degree of marketization, clustering, internationalization, and favorable local innovation policy system as well as unique Lingnan cultural. These institutions are highly compatible and closely coupled with each other, prohibiting and facilitating the innovation behavioral selection of various innovation actors. Based on the research findings, the paper proposes a series of policy recommendations to further strengthen the comparative advantage of innovation in the PRD region.

  20. Wang Jinzhen Attended the Forum on Cooperation & Development between Yangtze River Delta and Baltic Sea Region

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ On October 17,on behalf of CCPIT,Vice-Chairman Wang Jinzhen attended the opening ceremony of the 3rd Forum on Cooperation & Development between Yangtze River Delta Region of China and Baltic Sea Region of Europe,where he delivered a speech.

  1. Water Supply Deficiency and Implications for Rural Development in the Niger-Delta Region of Nigeria

    Science.gov (United States)

    Nkwocha, E. E.

    2009-01-01

    There is a growing concern about the marginalization of the Niger Delta region of Nigeria in terms of infrastructural and social services provision. This study examined the water supply deficiency and its general implications for rural development within the region. Data and other study characteristics were extracted from 501 subjects drawn from…

  2. Partial Root-Zone Drying (PRD) Feasibility on Potato in a Sub-Humid Climate

    DEFF Research Database (Denmark)

    Battilani, A; Jensen, C R; Liu, F;

    2014-01-01

    A field experiment was carried out in Northern Italy, within the frame of the EU project SAFIR, to test the feasibility of partial root-zone drying (PRD) irrigation management in potatoes and to compare the PRD irrigation strategy with regulated deficit irrigation (RDI). PRD increased total and f...... not steadily and not sufficiently to overcome the higher irrigation system and management costs.......A field experiment was carried out in Northern Italy, within the frame of the EU project SAFIR, to test the feasibility of partial root-zone drying (PRD) irrigation management in potatoes and to compare the PRD irrigation strategy with regulated deficit irrigation (RDI). PRD increased total...... Efficiency (WUE, NUE) were similar between irrigation treatments. The income for each cubic meter of water or kg of nitrogen was highly variable and not statistically different between PRD and RDI. Crop gross margin per hectare shows a tendency to increase with PRD (average +256 euro ha-1), although...

  3. Ecological Niche Modeling Identifies Fine-Scale Areas at High Risk of Dengue Fever in the Pearl River Delta, China

    Directory of Open Access Journals (Sweden)

    Qiaoxuan Li

    2017-06-01

    Full Text Available Dengue fever (DF is one of the most common and rapidly spreading mosquito-borne viral diseases in tropical and subtropical regions. In recent years, this imported disease has posed a serious threat to public health in China, especially in the Pearl River Delta (PRD. Although the severity of DF outbreaks in the PRD is generally associated with known risk factors, fine scale assessments of areas at high risk for DF outbreaks are limited. We built five ecological niche models to identify such areas including a variety of climatic, environmental, and socioeconomic variables, as well as, in some models, extracted principal components. All the models we tested accurately identified the risk of DF, the area under the receiver operating characteristic curve (AUC were greater than 0.8, but the model using all original variables was the most accurate (AUC = 0.906. Socioeconomic variables had a greater impact on this model (total contribution 55.27% than climatic and environmental variables (total contribution 44.93%. We found the highest risk of DF outbreaks on the border of Guangzhou and Foshan (in the central PRD, and in northern Zhongshan (in the southern PRD. Our fine-scale results may help health agencies to focus epidemic monitoring tightly on the areas at highest risk of DF outbreaks.

  4. Partial Root-Zone Drying (PRD) Feasibility on Potato in a Sub-Humid Climate

    DEFF Research Database (Denmark)

    Battilani, A; Jensen, C R; Liu, F

    2014-01-01

    A field experiment was carried out in Northern Italy, within the frame of the EU project SAFIR, to test the feasibility of partial root-zone drying (PRD) irrigation management in potatoes and to compare the PRD irrigation strategy with regulated deficit irrigation (RDI). PRD increased total and f...

  5. Formation of Solar Delta Active Regions:Twist and Writhe of Magnetic Ropes

    Institute of Scientific and Technical Information of China (English)

    Hong-Qi Zhang

    2004-01-01

    We analyze the process of formation of delta configuration in some well-known super active regions based on photospheric vector magnetogram observations. It is found that the magnetic field in the initial developing stage of some delta active regions shows a potential-like configuration in the solar atmosphere,the magnetic shear develops mainly near the magnetic neutral line with magnetic islands of opposite polarities, and the large-scale photospheric twisted field forming gradually later. Some results are obtained: (1) The analysis of magnetic writhe of whole active regions cannot be limited in the strong field of sunspots, because the contribution of the fraction of decayed magnetic field is non-negligible. (2) The magnetic model of kink magnetic ropes, supposed to be generated in the subatmosphere,is not consistent with the evolution of large-scale twisted photospheric transverse magnetic field and not entirely consistent with the relationship with magnetic shear in some delta active regions. (3) The proposition is that the large-scale delta active regions are formed from contribution by small-scale non-potential magnetic flux bundles generated in the subatmosphere.

  6. Bioaccumulation and risk assessment of per- and polyfluoroalkyl substances in wild freshwater fish from rivers in the Pearl River Delta region, South China.

    Science.gov (United States)

    Pan, Chang-Gui; Zhao, Jian-Liang; Liu, You-Sheng; Zhang, Qian-Qian; Chen, Zhi-Feng; Lai, Hua-Jie; Peng, Feng-Jiao; Liu, Shuang-Shuang; Ying, Guang-Guo

    2014-09-01

    Per- and polyfluoroalkyl substances (PFASs) are used in various industries, which results in their ubiquitous occurrence in the environment. This study determined the concentrations of eighteen PFASs in muscle and liver of nine wild freshwater fish species collected from rivers in the Pearl River Delta (PRD) region, South China, and assessed their bioaccumulation and potential health risks to local people. The results showed that eight and twelve PFASs were detected in the fish muscle and liver samples, respectively. Perfluorooctane sulfonate (PFOS) was found to be the predominant PFAS both in muscle and liver with its highest concentrations of 79ng/g wet weight (ww) in muscle and 1500ng/g ww in liver, followed by Perfluoroundecanoic acid (PFUnDA) and Perfluorotridecanoic acid (PFTrDA) with trace concentrations. The mean PFOS concentrations in fish muscle and liver tissues of the nine collected species ranged from 0.40ng/g in mud carp to 25ng/g in snakehead, and from 5.6ng/g in mud carp to 1100ng/g in snakehead, respectively. Significant positive correlations were found among PFASs both in water and fish, indicating a similar pollution source for these PFASs. In tilapia samples, PFOS concentrations showed an increasing trend with increasing length and weight, but no significant difference between genders. Bioaccumulation factors (logBAF) in fish for the PFASs were in the range from 2.1 to 5.0. The calculated hazard ratios (HR) of PFOS for all fishes were in the range of 0.05-2.8, with four out of nine species (tilapia, chub, leather catfish and snakehead) having their HR values more than 1.0. The results suggest that frequent consumption of these four fish species may pose health risks to local population.

  7. Changes in visibility with PM2.5 composition and relative humidity at a background site in the Pearl River Delta region.

    Science.gov (United States)

    Fu, Xiaoxin; Wang, Xinming; Hu, Qihou; Li, Guanghui; Ding, Xiang; Zhang, Yanli; He, Quanfu; Liu, Tengyu; Zhang, Zhou; Yu, Qingqing; Shen, Ruqing; Bi, Xinhui

    2016-02-01

    In fall-winter, 2007-2013, visibility and light scattering coefficients (bsp) were measured along with PM2.5 mass concentrations and chemical compositions at a background site in the Pearl River Delta (PRD) region. The daily average visibility increased significantly (p<0.01) at a rate of 1.1 km/year, yet its median stabilized at ~13 km. No haze days occurred when the 24-hr mean PM2.5 mass concentration was below 75 μg/m(3). By multiple linear regression on the chemical budget of particle scattering coefficient (bsp), we obtained site-specific mass scattering efficiency (MSE) values of 6.5 ± 0.2, 2.6 ± 0.3, 2.4 ± 0.7 and 7.3 ± 1.2m(2)/g, respectively, for organic matter (OM), ammonium sulfate (AS), ammonium nitrate (AN) and sea salt (SS). The reconstructed light extinction coefficient (bext) based on the Interagency Monitoring of Protected Visual Environments (IMPROVE) algorithm with our site-specific MSE revealed that OM, AS, AN, SS and light-absorbing carbon (LAC) on average contributed 45.9% ± 1.6%, 25.6% ± 1.2%, 12.0% ± 0.7%, 11.2% ± 0.9% and 5.4% ± 0.3% to light extinction, respectively. Averaged bext displayed a significant reduction rate of 14.1/Mm·year (p<0.05); this rate would be 82% higher if it were not counteracted by increasing relative humidity (RH) and hygroscopic growth factor (f(RH)) at rates of 2.5% and 0.16/year(-1) (p<0.01), respectively, during the fall-winter, 2007-2013. This growth of RH and f(RH) partly offsets the positive effects of lowered AS in improving visibility, and aggravated the negative effects of increasing AN to impair visibility.

  8. The oil rich Niger Delta region: a framework for improved performance of the Nigerian regulatory process.

    Science.gov (United States)

    Onu, N Chukemeka Hemanachi

    2003-06-01

    The adoption of this policy framework has the ability to reconcile industry, the environment and community interests, taking into account all factors that are relevant to managing developments that are both sustainable and contributory to the achievement of industrial and community stability. The management of resource development is crucial in sustaining the Niger Delta ecosystem and the human population resident in the Niger Delta region. If these separate bodies are constituted they would have the potential to reduce and discourage: i) the vulnerability of the regulatory body to influential and powerful multinational oil companies; ii) the proclivity for unaccountability to the people of the Niger Delta region, since the people of the Niger Delta would have access to the regulatory body's classified and unclassified information, and are part of the decision-making process; and iii) a reduction in conflict between the oil mining companies and the aggrieved youths of the oil rich Niger Delta region. This policy framework also has the added advantage of producing high quality decisions and more acceptable decisions than those for which the people of the Niger Delta region are excluded from the processes that concern their existence. The agency decision-making could now become a multilateral process and thus promote and enhance the accurate, impartial and rational application of legislative directives to given cases or classes of cases. Most importantly, the Minister of Petroleum Resources should be empowered by legislation to revoke any license or lease in respect of an area designated as marginal if left undeveloped for a period of 5 years and grant a lease or license for the area to a more responsible oil company.

  9. Chiral Effective-Field Theory in the $\\Delta$(1232) Region: I. Pion Electroproduction on the Nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Vladimir Pascalutsa; Marc Vanderhaeghen

    2006-01-20

    We develop an extension of chiral perturbation theory to the {Delta}(1232)-resonance energy region and apply it to investigate the pion electroproduction off the nucleon (e{sup -} N {yields} e{sup -} N {pi}). We present a complete calculation of this process, in the {Delta}-resonance region, up to next-to-leading order in the {delta}-expansion. At this order, the only free parameters are the three low-energy constants corresponding to the magnetic (M1), electric (E2), and Coulomb (C2) {gamma} N {yields} {Delta} transition strength. After fitting these parameters to a few well-known data, our calculation provides a prediction for observables and multipole amplitudes of pion electroproduction. These results compare favorably with the phenomenological multipole solutions and recent experimental results from MIT-Bates and MAMI. Our prediction for the pion-mass dependence of the {gamma}N{Delta} form factors offers an explanation for the discrepancy between the recent lattice-QCD results and the experimental value for the ''C2/M1 ratio'' at low Q{sup 2}.

  10. Regional controls on geomorphology, hydrology, and ecosystem integrity in the Orinoco Delta, Venezuela

    Science.gov (United States)

    Warne, Andrew G.; Meade, Robert H.; White, William A.; Guevara, Edgar H.; Gibeaut, James; Smyth, Rebecca C.; Aslan, Andres; Tremblay, Thomas

    2002-05-01

    Interacting river discharge, tidal oscillation, and tropical rainfall across the 22,000 km 2 Orinoco delta plain support diverse fresh and brackish water ecosystems. To develop environmental baseline information for this largely unpopulated region, we evaluate major coastal plain, shallow marine, and river systems of northeastern South America, which serves to identify principal sources and controls of water and sediment flow into, through, and out of the Orinoco Delta. The regional analysis includes a summary of the geology, hydrodynamics, sediment dynamics, and geomorphic characteristics of the Orinoco drainage basin, river, and delta system. Because the Amazon River is a major source of sediment deposited along the Orinoco coast, we summarize Amazon water and sediment input to the northeastern South American littoral zone. We investigate sediment dynamics and geomorphology of the Guiana coast, where marine processes and Holocene history are similar to the Orinoco coast. Major factors controlling Orinoco Delta water and sediment dynamics include the pronounced annual flood discharge; the uneven distribution of water and sediment discharge across the delta plain; discharge of large volumes of water with low sediment concentrations through the Rı´o Grande and Araguao distributaries; water and sediment dynamics associated with the Guayana littoral current along the northeastern South American coast; inflow of large volumes of Amazon sediment to the Orinoco coast; development of a fresh water plume seaward of Boca Grande; disruption of the Guayana Current by Trinidad, Boca de Serpientes, and Gulf of Paria; and the constriction at Boca de Serpientes.

  11. Delft Delta Design: The Houston Galveston Bay Region, Texas, USA

    NARCIS (Netherlands)

    Kothuis, B.L.M.; Brand, A.D.; Sebastian, A.G.; Nillesen, A.L.; Jonkman, S.N.

    2015-01-01

    In 2008, Hurricane Ike devastated Bolivar Peninsula, narrowly missing the more heavily industrialized and populated areas in the region. In the aftermath of the hurricane, the Severe Storm Prediction, Education and Evacuation from Disasters (SSPEED) Center at Rice University in Houston, and Texas A&

  12. Towards ending conflict and insecurity in the Niger Delta region: A ...

    African Journals Online (AJOL)

    2017-08-28

    Aug 28, 2017 ... life insecure. In the Niger Delta, violence has been the bane of the region .... outside the country and during the period, relative peace returned to the ... to new lands … while decreases in wealth can cause deprivation conflicts.

  13. Towards Deriving Renewable Energy from Aquatic Macrophytes Polluting Water Bodies in Niger Delta Region of Nigeria

    Directory of Open Access Journals (Sweden)

    Badmus Abdurrahman Adeleye

    2013-01-01

    Full Text Available This study was performed to derive methane rich biogas from biomass of harvested water hyacinth polluting water bodies in selected rivers of the Niger delta region of Nigeria. Field visits were undertaken on selected rivers in the Niger Delta region in which aquatic macrophytes were collected and inventorized. Also different types of aquatic macrophytes were surveyed. Control by harvesting macrophytes and deriving energy (methane-rich biogas from biomass of one (water hyacinth was successfully carried out in this study. An initial test was conducted to evaluate methane rich biogas production from water hyacinth collected from the wild. After a successful production of combustible biogas, laboratory experiments aimed at generating biogas from harvested biomass of aquatic mycrophyte (water hyacinth cultivated under eutrophic and oligotrophic conditions were undertaken in the laboratory. The result of the study showed highest biogas yield of 22 L over a 40 day retention time for water hyacinth raised under eutrophic conditions. Biogas yield for water hyacinth raised under oligotrophic conditions recorded the highest yield of 53L over an 11 day retention time. The conversion of the biomass of harvested aquatic macrophyte (water hyacinth from the Niger Delta into renewable energy, that is combustible biogas, demonstrated an inevitable option for the control and management of environmental pollution associated with aquatic macrophytes and their usability for poverty alleviation in the Niger Delta region of Nigeria.

  14. Virtual versus Real Nuclear Compton Scattering in the $\\delta$(1232) region

    CERN Document Server

    Gil, A; Oset, E

    1996-01-01

    In this paper we calculate the cross section for Virtual Compton Scattering off nuclei in the delta resonance region. We also calculate the background for the process from Coherent Bremsstrahlung in nuclei and explore the regions where the Virtual Compton Scattering cross section dominates. The study also shows that it is possible to extract the cross section for Real Compton Scattering from the Virtual Compton one in a wide range of scattering angles.

  15. Virtual versus real nuclear Compton scattering in the {Delta}(1232) region

    Energy Technology Data Exchange (ETDEWEB)

    Gil, A. [Univ. de Valencia, Burjassot (Spain). Dept. de Fisica Teorica; Gomez Tejedor, J.A. [Univ. de Valencia, Burjassot (Spain). Dept. de Fisica Teorica; Oset, E. [Univ. de Valencia, Burjassot (Spain). Dept. de Fisica Teorica

    1997-03-10

    In this paper we calculate the cross section for virtual Compton scattering off nuclei in the delta resonance region. We also calculate the background for the process from coherent bremsstrahlung in nuclei and explore the regions where the virtual Compton scattering cross section dominates. The study also shows that it is possible to extract the cross section for real Compton scattering from the virtual Compton one in a wide range of scattering angles. (orig.).

  16. Influences of relative humidity and particle chemical composition on aerosol scattering properties during the 2006 PRD campaign

    Science.gov (United States)

    Liu, Xingang; Cheng, Yafang; Zhang, Yuanhang; Jung, Jinsang; Sugimoto, Nobuo; Chang, Shih-Yu; Kim, Young J.; Fan, Shaojia; Zeng, Limin

    In situ measurements of the physical, chemical, and optical properties of aerosols were carried out in Guangzhou city, China, from 1 to 31 July 2006 during the Pearl River Delta (PRD) Campaign. The light extinction coefficient of the ambient atmosphere, the aerosol scattering coefficient under dry conditions, the aerosol absorption coefficient under ambient conditions, NO 2 concentration, and relative humidity (RH) were measured by transmissionmeter, an integrating nephelometer, a multi-angle absorption photometer (MAAP), a NO X analyzer, and an automatic meteorological station, respectively. Meanwhile, the molecular scattering coefficient was calculated by the Rayleigh scattering function using the US Standard Atmosphere. A method to calculate the aerosol hygroscopic growth factor f(RH), defined as the ratio of the aerosol scattering coefficient under a wet condition to that under a dry condition (40% RH), is proposed based on these optical parameters. The mean and standard deviation aerosol hygroscopic growth factors at 80% RH ( f(RH)=80%) in Ganzhou were 2.04±0.28, 2.29±0.28, and 2.68±0.59 for urban aerosols, mixed aerosols, and marine aerosols, respectively, with the air mass classification being based on the air mass source region. The relationship between f(RH) and RH is fitted by empirical equations and the fitting parameters are calculated. The relationships between f(RH)=80% and total carbon mass fraction (TCF) in PM 2.5, the water-soluble mass fraction (WSF) in PM 10, and the sea-salt aerosol mass fraction (SSF) in PM 10 reveal that the hygroscopic properties of the observed aerosol have a good positive correlation with the WSF and SSF, but have a negative correlation with the TCF.

  17. Threshold of long-term survival of a coastal delphinid in anthropogenically degraded environment: Indo-Pacific humpback dolphins in Pearl River Delta

    Science.gov (United States)

    Karczmarski, Leszek; Huang, Shiang-Lin; Chan, Stephen C.Y.

    2017-01-01

    Defining demographic and ecological threshold of population persistence can assist in informing conservation management. We undertook such analyses for the Indo-Pacific humpback dolphin (Sousa chinensis) in the Pearl River Delta (PRD) region, southeast China. We use adult survival estimates for assessments of population status and annual rate of change. Our estimates indicate that, given a stationary population structure and minimal risk scenario, ~2000 individuals (minimum viable population in carrying capacity, MVPk) can maintain the population persistence across 40 generations. However, under the current population trend (~2.5% decline/annum), the population is fast approaching its viability threshold and may soon face effects of demographic stochasticity. The population demographic trajectory and the minimum area of critical habitat (MACH) that could prevent stochastic extinction are both highly sensitive to fluctuations in adult survival. For a hypothetical stationary population, MACH should approximate 3000-km2. However, this estimate increases four-fold with a 5% increase of adult mortality and exceeds the size of PRD when calculated for the current population status. On the other hand, cumulatively all current MPAs within PRD fail to secure the minimum habitat requirement to accommodate sufficiently viable population size. Our findings indicate that the PRD population is deemed to become extinct unless effective conservation measures can rapidly reverse the current population trend. PMID:28230056

  18. Oil exploitation and its socioeconomic effects on the Niger Delta region of Nigeria.

    Science.gov (United States)

    Elum, Z A; Mopipi, K; Henri-Ukoha, A

    2016-07-01

    The oil exploration and exploitation industry which is majorly centred in the Niger Delta region is without doubt currently the most important earner of foreign exchange to the Nigerian economy. The Niger Delta is home to an extraordinary variety of people; mostly fishers and farmers with a history of rich cultural heritage. However, the region is suffering from devastating oil pollution. Although the effects of oil spill depend on factors such as size or area of spill and geographical location, the socioeconomic and environmental costs of oil production can be extensive; these range from destruction of wildlife, biodiversity loss, air and water pollution, degradation of farmland and damage to aquatic ecosystems. The paper reviews the adverse effects of oil exploitation on the Niger Delta region. It researches the common belief that government and oil multinationals are negatively disposed to the socioeconomic and environmental wellbeing of host communities especially in events of oil spillage. The paper reveals that oil exploitation has increased the rate of environmental degradation and has perpetuated food insecurity as a result of death of fish and crops as well as loss of farm lands and viable rivers for fishing activities leading to loss of livelihood. The paper supports the call for multinationals operating in the region to modernise operating infrastructure and equipment in order to prevent avoidable oil spillages that often lead to community restiveness, and more so, intensification of joint efforts between oil multinationals and government in the capital development of the region is very important.

  19. Climate Change and Poverty: Sustainable Approach in the Niger Delta Region of Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Ogbeibu, A.E. [University of Benin, Benin City, Edo State (Nigeria). Department of Animal and Environmental Biology; Uyigue, E. [Community Research and Development Centre, Benin, Edo State (Nigeria)

    2008-09-30

    The Niger Delta region is the bedrock of Nigeria's oil production, which accounts for 97% of the government total revenue. Since the discovery of oil in the region, oil exploration and exploitation have caused severe climate and environmental changes which have impacted the lives of the inhabitant adversely. Prior to the discovery of oil, the people of the Niger Delta made their living from the exploitation of the resources of the land, water and forest as farmers, fishermen and hunters, this made them attached to and protective of their environment. The devastating impacts of the oil industries on farmland, crops, economic trees, creeks, lakes and other components of the environment are so severe that the people can no longer engage in productive farming, fishing and hunting as they use to do. The most affected groups are women and children. This paper highlights in details the climatic and environmental changes that have occurred in the Niger Delta region and shows the relationship between these changes and poverty. It reveals the weaknesses and deficiencies in the Nigerian Constitution in administering environmental rights to the people and suggests institutional and constitutional solution to the environmental degradation in the region and elsewhere.

  20. Hotspot of glyoxal over the Pearl River delta seen from the OMI satellite instrument: implications for emissions of aromatic hydrocarbons

    OpenAIRE

    Chan Miller, Christopher; Jacob, Daniel J.; González Abad, Gonzalo; Chance, Kelly

    2016-01-01

    The Pearl River delta (PRD) is a densely populated hub of industrial activity located in southern China. OMI (Ozone Monitoring Instrument) satellite observations reveal a large hotspot of glyoxal (CHOCHO) over the PRD that is almost twice as large as any other in Asia. Formaldehyde (HCHO) and NO2 observed by OMI are also high in the PRD but no more than in other urban/industrial areas of China. The CHOCHO hotspot over the PRD can be explained by industrial paint and solvent ...

  1. Sectorial water use trends in the urbanizing Pearl River Delta, China.

    Directory of Open Access Journals (Sweden)

    Mingtian Yao

    Full Text Available Assessing and managing water use is crucial for supporting sustainable river basin management and regional development. The first consistent and comprehensive assessment of sectorial water use in the Pearl River Delta (PRD is presented by analysing homogenized annual water use data from 2000 to 2010 in relation to socio economic statistics for the same period. An abstraction of water use, using the concept of water use intensity, and based on equations inspired by those used in global water resource models, is developed to explore the driving forces underlying water use changes in domestic, industrial and agricultural sectors. We do this at both the level of the region as a whole, as well as for the nine cities that constitute the PRD separately. We find that, despite strong population and economic growth, the PRD managed to stabilize its absolute water use by significant improvements in industrial water use intensities, and early stabilisation of domestic water use intensities. Results reveal large internal differentiation of sectorial water use among the cities in this region, with industrial water use intensity varying from -80 to +95% and domestic water use intensity by +/- 30% compared to the PRD average. In general, per capita water use is highest in the cities that industrialised first. Yet, all cities except Guangzhou are expected to approach a saturation value of per capita water use much below what is suggested in recent global studies. Therefore, existing global assessments probably have overestimated future domestic water use in developing countries. Although scarce and uncertain input data and model limitations lead to a high level of uncertainty, the presented conceptualization of water use is useful in exploring the underlying driving forces of water use trends.

  2. Sectorial water use trends in the urbanizing Pearl River Delta, China.

    Science.gov (United States)

    Yao, Mingtian; Werners, Saskia E; Hutjes, Ronald W A; Kabat, Pavel; Huang, Heqing

    2015-01-01

    Assessing and managing water use is crucial for supporting sustainable river basin management and regional development. The first consistent and comprehensive assessment of sectorial water use in the Pearl River Delta (PRD) is presented by analysing homogenized annual water use data from 2000 to 2010 in relation to socio economic statistics for the same period. An abstraction of water use, using the concept of water use intensity, and based on equations inspired by those used in global water resource models, is developed to explore the driving forces underlying water use changes in domestic, industrial and agricultural sectors. We do this at both the level of the region as a whole, as well as for the nine cities that constitute the PRD separately. We find that, despite strong population and economic growth, the PRD managed to stabilize its absolute water use by significant improvements in industrial water use intensities, and early stabilisation of domestic water use intensities. Results reveal large internal differentiation of sectorial water use among the cities in this region, with industrial water use intensity varying from -80 to +95% and domestic water use intensity by +/- 30% compared to the PRD average. In general, per capita water use is highest in the cities that industrialised first. Yet, all cities except Guangzhou are expected to approach a saturation value of per capita water use much below what is suggested in recent global studies. Therefore, existing global assessments probably have overestimated future domestic water use in developing countries. Although scarce and uncertain input data and model limitations lead to a high level of uncertainty, the presented conceptualization of water use is useful in exploring the underlying driving forces of water use trends.

  3. Simulation Analysis of Flight Delays in Pearl River Delta Region%珠三角地区航班延误的仿真分析

    Institute of Scientific and Technical Information of China (English)

    朱承元; 王馨悦; 刁琳

    2011-01-01

    Pearl River Delta region(PRD) suffers the problem of high-density airports,airspace congestion and a high delay of flights.It is necessary to research on the airspace and airport in PRD.The key points of PRD′s airspace and airport modeling based on SIMMOD(Airport and Airspace Simulation Model) are introduced.The SIMMOD model is validated by Theil′s inequality coefficients,and then the present flights delays and air traffic flow distribution in PRD are analyzed by SIMMOD Simulation.The air-ground situation under the maximum flights is simulated,and the bottlenecks of limiting flight flow in PRD are identified by the statistical analysis of the flight delays.%珠三角地区机场密集、空域紧张,导致该地区交通拥挤,航班延误高,迫切需要对其空域和机场进行研究。论文描述了采用空域机场仿真模型SIMMOD对珠三角地区的空域机场进行建模的关键点。采用THEIL不等式系数法对该SIMMOD模型进行了验证。分析了当前珠三角地区的航班延误和空中交通流量分布。仿真了未来最大航班量下的空中地面情况。通过统计分析航班延误,找出限制该地区飞行流量的瓶颈所在。

  4. Effect of PRD deficit-irrigation method and sodium salicylate on yield, yield components and water use efficiency of tomato

    Directory of Open Access Journals (Sweden)

    M. Meidanshahi

    2013-04-01

    Full Text Available To alleviate water scarcity problem in arid and semiarid regions of Iran, different irrigation methods such as deficit irrigation, pressurized irrigation and partial rootzone drying (PRD method have been suggested. In PRD method, half of the rootzone is watered and the other half is kept dry intermittently. The objective of this research was to study yield, yield components and water use efficiency (WUE of tomato, using PRD irrigation method and a growth stabilizer in two soil textures, under greenhouse conditions. The factorial experiment, based on complete randomizal design and three replications, included three irrigation managements (T1, full irrigation; T2, 50% of full irrigation, with PRD method and barrier; T3, 50% of full irrigation, with PRD method and no barrier, two levels of stabilizer (B1, spraying sodium salicylate and B2, without spraying sodium salicylate and two soil textures (S1, clay loam and S2, sandy loam. Results showed that the highest plants (176.2 cm were in T1 treatment and the shortest plants (131.3 cm were in T3 treatment. With 50% reduction of water in T2 compared to T1 treatment, number of flower stems was decreased by 15.2%. The highest and the least biomass and fruit yield were measured in T1 (506.8 and 342.5 g per plant and T3 (126.2 and 54.8 g per plant treatments, respectively. WUE was increased by 9.9% (changing from T1 to T2 and was decreased by 71.4% (changing from T2 to T3. The highest and the least fruit yield (216.7 and 174.4 g per plant were obtained in S2 and S1 soils, respectively. Sandy loam soil with production of 7.22 kg/m3 had higher WUE than clay loam soil, which produced 5.38 kg/m3. Application of stabilizer increased fruit yield by 16% and WUE by 16.86%. In general, the effect of PRD irrigation method (with barrier and spraying sodium salicylate on reducing water use and increasing productivity in greenhouse production of tomato was positive and recommendable.

  5. Electron beam asymmetry measurements from exclusive pi0 electroproduction in the Delta(1232) resonance region

    Energy Technology Data Exchange (ETDEWEB)

    K. Joo

    2003-05-01

    The polarized longitudinal-transverse structure function sigma_LT'in the p(e,e'p)pi^0 reaction has been measured for the first time in the Delta(1232) resonance region for invariant mass W = 1.1 - 1.3 GeV and at four-momentum transfer Q^2 = 0.40 and 0.65 GeV^2. Data were taken at the Thomas Jefferson National Accelerator Facility with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. This newly measured sigma_LT' provides new and unique information on the interference between resonant and non-resonant amplitudes in the Delta(1232) resonance region. The comparison to recent phenomenological calculations shows sensitivity to the description of non-resonant amplitudes and higher resonances.

  6. beta (+)-Thalassaemia in the Po river delta region (northern Italy): genotype and beta globin synthesis.

    Science.gov (United States)

    Del Senno, L; Pirastu, M; Barbieri, R; Bernardi, F; Buzzoni, D; Marchetti, G; Perrotta, C; Vullo, C; Kan, Y W; Conconi, F

    1985-01-01

    Six beta(+)-thalassaemic patients from the Po river delta region have been studied. Using synthetic oligonucleotides as specific hybridisation probes, the beta(+) IVS I mutation (G----A at position 108) was demonstrated. This lesion and the enzyme polymorphism pattern in the subjects examined are the same as have been described for other Mediterranean beta(+)-thalassaemias. Antenatal diagnosis through DNA analysis of beta(+)-thalassaemia is therefore possible. The production of beta globin in a beta(+), homozygote and in a beta (+), beta(0) 39 (nonsense mutation at codon 39) double heterozygote is approximately 20% and 10% respectively of total non-alpha globin synthesis. Despite some overlapping of the results, similar beta globin synthesis levels have been obtained in 43 beta(+)-thalassaemia patients. This suggests that in the Po river delta region the most common thalassaemic genes are beta(0) 39 and beta(+) IVS I. Images PMID:2580095

  7. Electron beam asymmetry measurements from exclusive pi0 electroproduction in the Delta(1232) resonance region

    Energy Technology Data Exchange (ETDEWEB)

    K. Joo

    2003-05-01

    The polarized longitudinal-transverse structure function sigma_LT'in the p(e,e'p)pi^0 reaction has been measured for the first time in the Delta(1232) resonance region for invariant mass W = 1.1 - 1.3 GeV and at four-momentum transfer Q^2 = 0.40 and 0.65 GeV^2. Data were taken at the Thomas Jefferson National Accelerator Facility with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. This newly measured sigma_LT' provides new and unique information on the interference between resonant and non-resonant amplitudes in the Delta(1232) resonance region. The comparison to recent phenomenological calculations shows sensitivity to the description of non-resonant amplitudes and higher resonances.

  8. Emergy Synthesis and Regional Sustainability Assessment: Case Study of Pan-Pearl River Delta in China

    OpenAIRE

    2014-01-01

    In this paper, emergy analysis is used in association with the ternary diagrams and geographic information system (GIS) tools to improve the evaluation of sustainability for the Pan-Pearl River Delta (PPRD) region. Emergy accounting of PPRD is estimated, and various emergy-based indicators are reported. Ternary diagrams are drawn to provide a graphical representation of the emergy accounting data. Finally, the GIS tools are employed to assist in the emergy-based spatial analysis, and emergy d...

  9. beta (+)-Thalassaemia in the Po river delta region (northern Italy): genotype and beta globin synthesis.

    OpenAIRE

    del Senno, L; Pirastu, M; Barbieri, R.; De Bernardi, F.; Buzzoni, D; Marchetti, G.; Perrotta, C; Vullo, C; Kan, Y W; Conconi, F

    1985-01-01

    Six beta(+)-thalassaemic patients from the Po river delta region have been studied. Using synthetic oligonucleotides as specific hybridisation probes, the beta(+) IVS I mutation (G----A at position 108) was demonstrated. This lesion and the enzyme polymorphism pattern in the subjects examined are the same as have been described for other Mediterranean beta(+)-thalassaemias. Antenatal diagnosis through DNA analysis of beta(+)-thalassaemia is therefore possible. The production of beta globin in...

  10. Detection and Analysis of Coastline and Landuse Change from 1960 to 2012 in Pearl River Delta, China

    Science.gov (United States)

    Jin, Wang; Cao, Wenfang; Wu, Zhifeng; Tarolli, Paolo; Jia, Peng

    2017-04-01

    Coastline is the sea-land demarcation line in coastal regions. The position and shape of coastline depends on various natural and anthropogenic factors. The change of coastline exerts obvious influence on environment and economy in coastal regions. Therefore, it is important to detect and analysis the change of coastline and landuse for coastal environment and sustainable development. Pearl River Delta (PRD) is one of the most prosperous and fastest growing regions in China. The coastline and landuse in PRD have changed remarkably and continuously during the past decades. In this research, the change of coastline and landuse during 1960 to 2012 was detected with RS and GIS. Furthermore, coastline characteristics of temporal and spatial variation were analyzed with quantitative and spatial approach. And the relationship between the changes of coastline and landuse was explored. Therefore, the impact that urban expansion brought to landscape in coastal zone could be quantitatively analyzed. Finally, local government management on coastal wetland was discussed. The main outcomes of this research are summarized in the following points: (1) The length of coastline in PRD increased from 1134.95km to 1508.02km with annul increasing speed of 7.17km/a. Relatively, the coastline changed more obvious in three period (2004 2006, 2006 2008 and 2008 2010).The annual average change rate of coastline in the three period were -3.45%, 2.85% and 2.98%, respectively. After 2010, the speed of coastline change in PRD became lower. (2) The coastline had a greater increasing amount in the cities of Zhuhai, Guangzhou and Shenzhen, where the length of coastline increased 60.81%, 22.00%and 19.71%, respectively. (3) Nansha in Guangzhou, south Zhuhai and Qianhai in Shenzhen gained more newly-added land than any other area in PRD. Their land area increased from 172.34km2 to 303.22km2, 344.70km2 to 603.29km2 and89.62km2 to 145.49km2, respectively. (4) In PRD, construction land expanded 33 times

  11. Identifying hotspots and management of critical ecosystem services in rapidly urbanizing Yangtze River Delta Region, China.

    Science.gov (United States)

    Cai, Wenbo; Gibbs, David; Zhang, Lang; Ferrier, Graham; Cai, Yongli

    2017-04-15

    Rapid urbanization has altered many ecosystems, causing a decline in many ecosystem services, generating serious ecological crisis. To cope with these challenges, we presented a comprehensive framework comprising five core steps for identifying and managing hotspots of critical ecosystem services in a rapid urbanizing region. This framework was applied in the case study of the Yangtze River Delta (YRD) Region. The study showed that there was large spatial heterogeneity in the hotspots of ecosystem services in the region, hotspots of supporting services and regulating services aggregately distributing in the southwest mountainous areas while hotspots of provisioning services mainly in the northeast plain, and hotspots of cultural services widespread in the waterbodies and southwest mountainous areas. The regionalization of the critical ecosystem services was made through the hotspot analysis. This study provided valuable information for environmental planning and management in a rapid urbanizing region and helped improve China's ecological redlines policy at regional scale. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Water Management Strategy in Assessing the Water Scarcity in Northern Western Region of Nile Delta, Egypt

    Science.gov (United States)

    Mabrouk, Badr; Arafa, Salah; Gemajl, Khaled

    2015-04-01

    Sustainable development in the Nile Delta of Egypt is retarded by serious environmental problems, where land-use and land-cover of the region are subjected to continuous changes; including shoreline changes either by erosion or accretion, subsidence of the delta, as well as by sea level rise due to climate change. The current research attempts to; (1) study the vulnerability of the northern western region of the Nile Delta coastal zone to climate change/sea level rise while setting basic challenges, review adaptation strategies based on adaptation policy framework, and highlight recommended programs for preparedness to climate change, (2) study the scarcity of water resources in the area of study with review of the socioeconomic impacts and the critical need of establishing desalination plants with new standards assessing the environmental situation and population clusters, and (3) monitor of the brine water extracted from the desalination plants and injected to subsurface strata. This monitoring process is divided into 3 main directions: 1) studying the chemical characteristics of water extracted from the water desalinations plants qualitatively and quantitatively. 2) mapping the subsurface of which that brine water will be injected to it and the flow directions and effects using resistivity data, and 3) using GIS and suitable numerical models in order to study the effect, volume, flow of the brine water and its long term environmental impacts on the area. The results indicate that the area is particularly vulnerable to the impact of SLR, salt water intrusion, the deterioration of coastal tourism and the impact of extreme dust storms. This in turn will directly affect the agricultural productivity and human settlements in coastal zones. The paper presents different scenarios for water management and recommends the most suitable scenarios in order to establish a core for water management strategy in the region according to existing socio-economic and environmental

  13. Identification Of Hydrocarbon Regions In Southern Niger Delta Basin Of Nigeria From Potential Field Data

    Directory of Open Access Journals (Sweden)

    Eke

    2015-08-01

    Full Text Available Potential hydrocarbon regions in the southern region of the Niger delta Basin of Nigeria have been identified from gravity and magnetic data. The enhanced residual data obtained from least square analysis method was interpreted by inverse and forward modeling techniques using Potent-3D software. The results reveal potential hydrocarbon environment at depths of between 1000 m to 3 500 m from the gravity data and depths of 2183 m to 4385 m from the magnetic data. The identified structures trend in NS EW and NE-SW directions of the basin.

  14. Towards assessing the social sustainability performance of the petroleum industry in the Niger Delta Region of Nigeria

    CSIR Research Space (South Africa)

    Bubou, GM

    2009-05-01

    Full Text Available Unresolved social issues between the local community and the petroleum industry plague the Niger Delta Region of Nigeria. These concerns are addressed by introducing a social sustainability assessment framework for the petroleum industry. Key...

  15. Characterization and risk assessment of polychlorinated biphenyls in soils and rice tissues in a suburban paddy field of the Pearl River Delta, South China.

    Science.gov (United States)

    Li, Qilu; Wang, Yan; Luo, Chunling; Li, Jun; Zhang, Gan

    2015-08-01

    We investigated the concentration and composition of polychlorinated biphenyls (PCBs) in paddy soils and rice tissues and the associated potential health risks in the urban agricultural areas of the Pearl River Delta (PRD), South China. The results indicated that highly chlorinated PCBs were more prominent in soil when the concentrations of low-molecular-weight PCBs were relatively high in rice plants. There was a trend of decreasing PCB concentrations with soil depth and a significant correlation between PCBs and the total organic carbon or total nitrogen concentration in section soils. The PCB concentrations followed the order of root > leaf > stem > grain. Although the dioxin toxicity equivalency values and estimated daily intake levels (based direct and indirect consumption) were lower than in other seriously contaminated regions, there is still a need to monitor PCB pollution in urban agriculture because of the PCB emissions from capacitor storage following the rapid urbanization experienced in the PRD.

  16. Distribution of antibiotics in wastewater-irrigated soils and their accumulation in vegetable crops in the Pearl River Delta, southern China.

    Science.gov (United States)

    Pan, Min; Wong, Chris K C; Chu, L M

    2014-11-19

    Wastewater is increasingly being used to irrigate agricultural land in many countries around the world. However, limited research has examined the occurrence of antibiotics in soil irrigated with wastewater and their accumulation in plants. This study aimed to determine the distribution of various types of antibiotics in different environmental matrices in the Pearl River Delta (PRD) region and to evaluate their accumulation and translocation in edible crops. Samples were collected from six sites in the PRD where either domestic wastewater or fishpond water was used for irrigation. Results showed that fishpond water irrigated soils had higher concentrations of antibiotics than wastewater-irrigated soils. Different trends were observed in the accumulation of antibiotics in the different edible parts of various crops. Despite the low human annual exposure to antibiotics through the consumption of edible crops (1.10 to 7950 μg/y), the potential adverse effects of antibiotics along the food chain should not be neglected.

  17. Fate of linear alkylbenzenes and benzothiazoles of anthropogenic origin and their potential as environmental molecular markers in the Pearl River Delta, South China

    Energy Technology Data Exchange (ETDEWEB)

    Ni Honggang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Shen Rulang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Zeng Hui [Key Laboratory for Environmental and Urban Sciences, Shenzhen Graduate School, Peking University, Shenzhen 518055 (China); Zeng, Eddy Y., E-mail: eddyzeng@gig.ac.c [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2009-12-15

    The mass emissions of linear alkylbenzenes (LABs), benzothiazole (BT), and 2-[4-morpholinyl]benzothiazole (24MoBT) from anthropogenic activities within one year were estimated according to the population and the number of automobiles in the Pearl River Delta (PRD), South China. Based on the estimation, the distribution of these compounds among various environmental media was simulated with a mass balance box model established in the present study. The results showed that 79% of LABs generated in the PRD was stored in sediment while only 1.3% of LABs was presumably transported to the adjacent South China Sea (SCS). On the contrary, 47% of BT and 77% of 24MoBT generated in the region were carried with riverine runoff to the coastal ocean. The results from the present study suggest that hydrophobic compounds tend to stay in the watershed of the PRD, whereas hydrophilic ones mainly outflow to the coastal ocean. - A simple mass balance box model examines the fate of linear alkylbenzenes and benzothiazoles in the Pearl River Delta, South China.

  18. Observationally-constrained carbonaceous aerosol source estimates for the Pearl River Delta area of China

    Science.gov (United States)

    Li, N.; Fu, T.-M.; Cao, J. J.; Zheng, J. Y.; He, Q. Y.; Long, X.; Zhao, Z. Z.; Cao, N. Y.; Fu, J. S.; Lam, Y. F.

    2015-11-01

    We simulated elemental carbon (EC) and organic carbon (OC) aerosols over the Pearl River Delta (PRD) area of China and compared the results to seasonal surface measurements, with the aim of quantifying carbonaceous aerosol sources from a "top-down" perspective. Our regional model was driven by current-best estimates of PRD EC (39.5 Gg C yr-1) and OC (32.8 Gg C yr-1) emissions and included updated secondary organic aerosol formation pathways. The simulated annual mean EC and OC concentrations were 4.0 and 7.7 μg C m-3, respectively, lower than the observed annual mean EC and OC concentrations (4.5 and 13.1 μg C m-3, respectively). We used multiple regression to match the simulated EC against seasonal mean observations. The resulting top-down estimate for EC emission in the PRD area was 52.9 ± 8.0 Gg C yr-1. We estimated the OC emission in the PRD area to be 60.2 ± 10.3 Gg C yr-1, based on the top-down EC emission estimate and the primary OC / EC ratios derived from bottom-up statistics. Using these top-down emission estimates, the simulated average annual mean EC and OC concentrations were improved to 4.4 and 9.5 μg C m-3, respectively, closer to the observations. Secondary sources accounted for 42 % of annual mean surface OC in our top-down simulations, with biogenic VOCs being the most important precursors.

  19. $\\delta$-Sunspot Formation in Simulation of Active-Region-Scale Flux Emergence

    CERN Document Server

    Fang, Fang

    2015-01-01

    $\\delta$-sunspots, with highly complex magnetic structures, are very productive in energetic eruptive events, such as X-class flares and homologous eruptions. We here study the formation of such complex magnetic structures by numerical simulations of magnetic flux emergence from the convection zone into the corona in an active-region-scale domain. In our simulation, two pairs of bipolar sunspots form on the surface, originating from two buoyant segments of a single subsurface twisted flux rope, following the approach of Toriumi et al. (2014). Expansion and rotation of the emerging fields in the two bipoles drive the two opposite polarities into each other with apparent rotating motion, producing a compact $\\delta$-sunspot with a sharp polarity inversion line. The formation of the $\\delta$-sunspot in such a realistic-scale domain produces emerging patterns similar to those formed in observations, e.g. the inverted polarity against Hale's law, the curvilinear motion of the spot, strong transverse field with hig...

  20. Challenges and Approaches in Delta Planning and Management - Sharing experiences from SE Asian Deltas and the Rhine-Meuse Delta -Report on Regional Training Workshop

    NARCIS (Netherlands)

    Long Phi, H.; Fida Abdullah Khan, M.; Wosten, J.H.M.; Douven, W.

    2014-01-01

    The training workshop consisted of a balanced mix of lectures on specific delta topics, work on group assignments, group and plenary discussions, and group presentations. Due to high professional level of the participants the discussions often reached the level of a policy dialogue among equals rath

  1. Humic-like substances in fresh emissions of rice straw burning and in ambient aerosols in the Pearl River Delta Region, China

    Directory of Open Access Journals (Sweden)

    P. Lin

    2010-07-01

    Full Text Available HUmic-LIke Substances (HULIS are an abundant unresolved mixture of organic compounds present in atmospheric samples. Biomass burning (BB has been recognized as an important primary source of HULIS, but measurements of HULIS in various fresh BB particles are lacking. In this work, HULIS in emissions of rice straw burning was measured in a number of field and chamber experiments. The average HULIS/OC ratio was 0.34±0.05 in μg/μgC, showing small variance among emissions under different burning conditions. The influence of BB on ambient HULIS levels was investigated by examining the spatial and temporal variation of HULIS and other aerosol constituents and interspecies relations in ambient PM2.5. The PM2.5 samples were collected at an urban and a suburban location in the Pearl River Delta (PRD, China over a period of one year. The HULIS concentrations in the ambient PM2.5 were significantly higher in air masses originating from regions influenced by BB. Significant correlations between HULIS and water-soluble K+ concentrations at both sites further support that BB was an important source of HULIS. Ambient concentrations of HULIS also correlated well with those of sulfate, oxalate, and oxidant (the sum of O3 and NO2. The HULIS/OC ratios in BB-influenced ambient aerosols (~0.6 were much higher than those in the fresh BB emissions (0.34, implying that secondary formation was also an important source of HULIS in the atmosphere. The annual average HULIS concentrations were 4.9 μg m−3 at the urban site and 7.1 μg m−3 at the suburban site while the annual average concentrations of elemental carbon were 3.3 μg m−3 and 2.4 μg m−3, respectively. The urban-suburban spatial gradient of HULIS was opposite to that of elemental carbon, negating vehicular exhaust as a significant primary emission source of HULIS.

  2. Retraction: Risks of avian influenza (H5) in duck farms in the Ayeyarwaddy Delta Region, Myanmar.

    Science.gov (United States)

    2014-05-01

    The following article from Zoonoses and Public Health, 'Risks of Avian Influenza (H5) in Duck Farms in the Ayeyarwaddy Delta Region, Myanmar' by H. H. Win, C. C. Su Mon, K. M. Aung, K. N. Oo, K. Sunn, T. Htun, T. Tiensin, M. Maclean, W. Kalpravidh and A. Amonsin published online on 09 August 2013 on Wiley Online Library (http://onlinelibrary.wiley. com/) has been retracted by the journal Editor-in-Chief, Mary Torrence, the Authors, and Blackwell Verlag GmbH, as the article has already been published in the Myanmar Veterinary Journal [Myanmar Veterinary Journal 2013, Vol. 15, No. 1, 43–50].

  3. Impact of nitrous acid chemistry on air quality modeling results over the Pearl River Delta region

    Directory of Open Access Journals (Sweden)

    R. Zhang

    2011-05-01

    Full Text Available The impact of nitrous acid chemistry on regional ozone and particulate matter in Pearl River Delta region was investigated using the Community Mutilscale Air Quality modeling system and the CB05 mechanism. Model simulations were conducted for a ten-day period in October 2004. Compared with available observed data, the model performance for NOx, SO2, PM10, and sulfate is reasonably good; however, predictions of HONO are an order of magnitude lower than observed data. The CB05 mechanism contains several homogenous reactions related to nitrous acid. To improve the model performance for nitrous acid, direct emissions, two heterogeneous reactions, and two surface photolysis reactions were incorporated into the model. The inclusion of the additional formation pathways significantly improved simulated nitrous acid compared with observed data. The addition of nitrous acid sources enhance daily maximum 8-h ozone by up to 6 ppb V (8 % and daily mean PM2.5 by up to 17 μg m−3 (12 %. They also affected ozone control strategy in Pearl River Delta region.

  4. Greenhouse gas emissions of different land uses in the delta region of Red River, Vietnam

    Science.gov (United States)

    Zhou, Minghua; Ha, Thu; An, Ngo The; Brüggemann, Nicolas

    2017-04-01

    Agricultural activities are responsible for up to a third of total anthropogenic GHG emissions. The subtropical/tropical delta areas of the large rivers in Southeast Asia are long-term history agricultural regions in the world. However, due to lack of field measurements, the estimation of the contribution of agro-ecosystems in the subtropical/tropical delta areas to global greenhouse gas emissions remains largely uncertain. Here, we conducted field experiments since January 2016 to quantify greenhouse gases (CO2, CH4 and N2O) emissions from four agricultural land uses of annual rice-rice, rice-vegetable, continuous vegetable system and fish pond in Red River delta region of Vietnam by using the transparent static chamber-gas chromatography technique. Higher N2O emissions were observed in the rice-vegetable and continuous vegetable systems, while lower N2O emissions were observed in the rice-rice and find pond systems. Compared to rice-rice system the cumulative N2O fluxes were on average twenty-fold higher in the rice-vegetable and continuous vegetable systems but significantly lower (75%) in the fish pond. Overall the net CO2 sinks were observed in the rice-rice system while other three land uses of rice-vegetable, continuous vegetable and fish pond acted as the net CO2 sources. The rice-rice and fish pond showed net CH4 emissions while variations of CH4 emissions (i.e. shifting between sources and sinks) along variations of soil moisture and temperature were observed in rice-vegetable and continuous vegetable systems. Compared to rice-rice system, the cumulative CH4 fluxes were significantly decreased by 100% for continuous vegetable system, 94% for rice-vegetable system and 89% for fish pond. Overall, the data suggest that conversion of traditional rice-rice paddy system to rice-vegetable, continuous vegetable system and find pond, which are currently undergoing driven by the economical requests and environmental changes (e.g., salinity intrusion) in this delta

  5. Ral GTPase interacts with the N-terminal in addition to the C-terminal region of PLC-delta1.

    Science.gov (United States)

    Grujic, Ognjen; Bhullar, Rajinder P

    2009-06-12

    Previously, we have shown that RalA, a calmodulin (CaM)-binding protein, binds to the C2 region in the C-terminal of PLC-delta1, and increases its enzymatic activity. Since PLC-delta1 contains a CaM-like region in its N-terminus, we have investigated if RalA can also bind to the N-terminus of PLC-delta1. Therefore, we created a GST-PLC-delta1 construct consisting of the first 294 amino acids of PLC-delta1 (GST-PLC-delta1(1-294)). In vitro binding experiments confirmed that PLC-delta1(1-294) was capable of binding directly to RalA. W-7 coupled to polyacrylamide beads bound pure PLC-delta1, demonstrating that PLC-delta1 contains a CaM-like region. Competition assays with W-7, peptides representing RalA and the newly identified RalB CaM-binding regions, or the IQ peptide from PLC-delta1 were able to inhibit RalA binding to PLC-delta1(1-294). This study demonstrates that there are two binding sites for RalA in PLC-delta1 and provides further insight into the role of Ral GTPase in the regulation of PLC-delta1 function.

  6. Quasi-free Pi0 and Pi- electroproduction on 4He in the Delta-resonance region (Pi en Delta in symbolen) - Zie als voorbeeld titelblad -

    NARCIS (Netherlands)

    Steenbakkers, M.F.M.

    2004-01-01

    The reactions 4He(e, e' p3He)pi- and 4He(e, e' p3He)pi0 were studied simultaneously, and for the first time, in a large kinematical domain including the Delta-resonance region. This was achieved by detecting the recoiling 3He and 3H nuclei instead of the emitted pions. The dependences of the cross

  7. Regional contribution to PM1 pollution during winter haze in Yangtze River Delta, China.

    Science.gov (United States)

    Tang, Lili; Yu, Hongxia; Ding, Aijun; Zhang, Yunjiang; Qin, Wei; Wang, Zhuang; Chen, Wentai; Hua, Yan; Yang, Xiaoxiao

    2016-01-15

    To quantify regional sources contributing to submicron particulate matter (PM1) pollution in haze episodes, on-line measurements combining two modeling methods, namely, positive matrix factorization (PMF) and backward Lagrangian particle dispersion modeling (LPDM), were conducted for the period of one month in urban Nanjing, a city located in the western part of Yangtze River Delta (YRD) region of China. Several multi-day haze episodes were observed in December 2013. Long-range transport of biomass burning from the southwestern YRD region largely contributed to PM1 pollution with more than 25% of total organics mass in a lasting heavy haze. The LPDM analysis indicates that regional transport is a main source contributing to secondary low-volatility production. The high-potential source regions of secondary low-volatility production are mainly located in areas to the northeast of the city. High aerosol pollution was mainly contributed by regional transport associated with northeastern air masses. Such regional transport on average accounts for 46% of total NR-PM1 with sulfate and aged low-volatility organics being the largest fractions (>65%).

  8. Oil Exploration and the Dilemma of Unemployment in the Niger-Delta Region of Nigeria

    Directory of Open Access Journals (Sweden)

    Nwosu Jonathan E

    2016-02-01

    Full Text Available The Niger delta region situated in the southern part of Nigeria covers a territory of about 112,110 km2, which represents about 12 % of the total area of the country. The Niger delta is an oil-rich region, which has led Nigeria to the 12th place among the oil producing countries of the world. The share of crude oil production accounts for 90 % of export revenues and 75% of the total state revenue. However, despite the numerous social and economic achievements of the oil industry, it is considered to be the cause of the unemployment rate growth in the region. Taking into account the abovementioned, the aim of this article is to evaluate the relationship of the crude oil production and high unemployment rate in the Niger Delta. In the article there applied the method of non-experimental research to enable the proportional reflection, method of cluster random choice for distribution of questionnaires and interviewing method for obtaining direct data and information. The results showed that the ecological damage caused by the oil production has had a negative impact on the fishing and agriculture — the main activities of the region rural population. In other words, the threat of oil spills, gas flaring, pollution and other activities associated with oil production are destroying the environment, which is the main home and source of income for a large number of working-age population. Thus, as a result of the depletion of fertile soils, the crop yield drops or completely disappears, forests vanish together with their resources. Rivers and reservoirs are being polluted resulting in the extinction of fish and river fauna, which, in turn, leads to the fact that fishermen and farmers, whose work is directly dependent on environmental conditions, are affected by unemployment. This causes a widespread poverty, unrest and hostile attitude of among young people, as well as the emergence of other social problems prevailing in the region. Unfortunately, the

  9. Carbonyl sulfide, dimethyl sulfide and carbon disulfide in the Pearl River Delta of southern China: Impact of anthropogenic and biogenic sources

    Science.gov (United States)

    Guo, H.; Simpson, I. J.; Ding, A. J.; Wang, T.; Saunders, S. M.; Wang, T. J.; Cheng, H. R.; Barletta, B.; Meinardi, S.; Blake, D. R.; Rowland, F. S.

    2010-10-01

    Reduced sulfur compounds (RSCs) such as carbonyl sulfide (OCS), dimethyl sulfide (DMS) and carbon disulfide (CS 2) impact radiative forcing, ozone depletion, and acid rain. Although Asia is a large source of these compounds, until now a long-term study of their emission patterns has not been carried out. Here we analyze 16 months of RSC data measured at a polluted rural/coastal site in the greater Pearl River Delta (PRD) of southern China. A total of 188 canister air samples were collected from August 2001 to December 2002. The OCS and CS 2 mixing ratios within these samples were higher in autumn/winter and lower in summer due to the influence of Asian monsoon circulations. Comparatively low DMS values observed in this coastal region suggest a relatively low biological productivity during summer months. The springtime OCS levels in the study region (574 ± 40 pptv) were 25% higher than those on other East Asia coasts such Japan, whereas the springtime CS 2 and DMS mixing ratios in the PRD (47 ± 38 pptv and 22 ± 5 pptv, respectively) were 3-30 times lower than elevated values that have been measured elsewhere in East Asia (Japan and Korea) at this time of year. Poor correlations were found among the three RSCs in the whole group of 188 samples, suggesting their complex and variable sources in the region. By means of backward Lagrangian particle release simulations, air samples originating from the inner PRD, urban Hong Kong and South China Sea were identified. The mean mixing ratio of OCS in the inner PRD was significantly higher than that in Hong Kong urban air and South China Sea marine air ( p 0.05). Using a linear regression method based on correlations with the urban tracer CO, the estimated OCS emission in inner PRD (49.6 ± 4.7 Gg yr -1) was much higher than that in Hong Kong (0.32 ± 0.05 Gg yr -1), whereas the estimated CS 2 and DMS emissions in the study region accounted for a very few percentage of the total CS 2 and DMS emission in China. These

  10. [Spatial distribution and risk assessment of insecticides in surface soil from a rapidly urbanizing region].

    Science.gov (United States)

    Wei, Yan-Li; Bao, Lian-Jun; Wu, Cheng-Zhou; Zeng, Eddy Y

    2014-10-01

    To examine the distribution patterns of organic contaminants in rapidly urbanizing regions, the levels and spatial distributions of 19 overlooked insecticides, i. e., phenyl-pyrazole class (fipronil), chlordane, endosulfan, nonachlor, hexachlorobenzene, heptachlor, dieldrin, aldrin, endrin, methoxychlor and their metabolites, were examined in 229 soil samples collected from the Pearl River Delta (PRD) and surrounding areas. The results indicated that higher insecticide levels distributed in the central PRD, while lower levels congested in the surrounding areas. The similar spatial patterns between the levels of insecticides and economic prosperity or population density demonstrated that social-economic factors may have dictated the spatial patterns of insecticides. In addition, the changing of land-use types during urbanization processes, e.g., historical plowlands have been converted into residential landscapes, resulted in high concentrations of banned insecticides in metropolis of the central PRD. Source diagnostics indicated that new inputs of technical chlordane products existed in the PRD and surrounding areas. Fipronil was degraded into fipronil sulfone and fipronil sulfide in most soil samples because of its low half-life in soil. Finally, a risk assessment of 19 insecticides in soil for human health suggested that six samples collected from the major administrative districts with dense population had potential cancer or non-cancer risk to human health. Therefore, these overlooked insecticides should be concerned in future environmental research.

  11. Regional dynamics of persistent organic pollutants (POPs) in the Pearl River Delta, China: Implications and perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Kai [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate School, Chinese Academy of Sciences, Beijing 100049 (China); Zhang Baozhong [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Li Shaomeng [Environment Canada, 4905 Dufferin Street, Toronto, Ontario M3H 5T4 (Canada); Zeng, Eddy Y., E-mail: eddyzeng@gig.ac.cn [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2011-10-15

    The mass transport budgets of 1,1,1-trichloro-2,2-bis(chlorophenyl)ethane (p,p'-DDT) and decabromodiphenyl ether (BDE-209) in the Pearl River Delta, South China were calculated based on previously collected data. Residual p,p'-DDT, mostly related to historical use, has largely settled into soil (780,000 kg), while the soil BDE-209 inventory (44,000 kg) is considerably smaller. Conversely, large amounts of BDE-209 currently used in numerous commercial products have resulted in a much higher atmospheric depositional flux of BDE-209 (28,100 kg/yr) relative to p,p'-DDT (310 kg/yr). The soil inventory of p,p'-DDT is predicted to decrease to half of its current value after 22 years, and the percent area containing soil p,p'-DDT at levels exceeding the effects range-medium (27 ng/g) will decrease from 40% to 20%. Finally, soil BDE-209 inventory will reach an equilibrium value of 940 tons in {approx}60 years, when BDE-209 levels in 50% of soil will be above an equivalent risk guideline value (125 ng/g). - Highlights: > Transport budgets of p,p'-DDT and BDE-209 in the Pearl River Delta were built. > Dry aerial deposition is the dominant route to transport p,p'-DDT and BDE-209. > Soil inventory of p,p'-DDT is much larger than that of BDE-209. > Soil inventory of p,p'-DDT would decline to half of its current value in 22 years. > Soil BDE-209 inventory is expected to reach an equilibrium value in {approx}60 years. - Regional dynamics of p,p'-DDT and BDE-209 in the Pearl River Delta (South China) are examined and used to predict temporal variances.

  12. MODELLING OF SEDIMENTS CONCENTRATION DISTRIBUTION IN DREDGED CANALS OF THE NIGER DELTA ESTUARINE REGION, NIGERIA

    Directory of Open Access Journals (Sweden)

    Charles Chizom Dike

    2013-01-01

    Full Text Available Previous sediments concentration distributi on models used in the study of sediment characteristics of the dredged canals in the Niger-Delta estuarine region, Nigeria; did not take into consideration the lateral in flow due to tidal effects, which affects tremendously, the sediment intake into the estuarine waters. In the current research, existing models are modified by incorpora ting the missing lateral inflow parameters, which are peculiar to the Niger Delta environment, to obtain more accurate model results. Details are given herein, of the deve lopment and application of a 3-dimensional numerical model (EKU 2.8 Models to predict sediment concentration distribution (total suspended sediment & bed sediment load s in the Niger Delta estuarine canals, with Ekulama well 19 access canal as a case study. The approach in this paper involved coupling a sediment transport equation (w ith the inclusion of lateral inflow parameters, with an estuarine hydro-dy namics equation to generate a generic 3- dimensional sediment concentration distribu tion model, using deterministic approach. Predicted results using this model compar ed favorably with measured field results. Average sediment concentration of 29mg/l was obtained compared with 31mg/l measured in the field for bed sediment loads. Finally, the predicted sediment concentration distribution (TSS, when comp ared with field results, gave average correlation coefficient of 0.9.; hence, the present model will assist in generating adequate information /data on sediment ch aracteristics and transport mechanism, required for effective design of canals to redu ce rate of siltation. The application of the above knowledge/parameters generated from this model to effectively design canals to reduce siltation will be treated in subsequent articles.

  13. Examining the Impact of Nitrous Acid Chemistry on Ozone and PM over the Pearl River Delta Region

    Science.gov (United States)

    The impact of nitrous acid (HONO) chemistry on regional ozone and particulate matter in Pearl River Delta region was investigated using the community multiscale air quality (CMAQ) modeling system and the CB05 mechanism. Model simulations were conducted for a ten-day period in Oct...

  14. An estimate of the costs of an effective system of protected areas in the Niger Delta - Congo Basin Forest Region

    NARCIS (Netherlands)

    Blom, A.

    2004-01-01

    This paper presents an analysis of the costs of implementing a biodiversity conservation vision for the Niger Delta-Congo Basin Forest Region, a region covering the forests from Nigeria across Cameroon, Equatorial Guinea (EG), Gabon, Central African Republic (CAR), Congo and the Democratic Republic

  15. Partial root zone drying (PRD) sustains yield of potatoes (Solanum tuberosum L.) at reduced water supply

    DEFF Research Database (Denmark)

    Shahnazari, Ali; Andersen, Mathias Neumann; Liu, Fulai

    2008-01-01

    Partial root zone drying (PRD) is a new water-saving irrigation strategy being tested in many crop species. Until now it has not been investigated in potatoes (Solanum tuberosum L.). A field experiment on sandy soil in Denmark was conducted under a mobile rainout shelter to study effects of two...... irrigation. The reasons for a better tuber size distribution caused by PRD, however, remain elusive. For optimizing PRD irrigation, the crop physiological reactions to shifting intervals and level of irrigation reduction should be further studied at different growth stages....

  16. Partial root zone drying (PRD) sustains yield of potatoes (Solanum tuberosum L.) at reduced water supply

    DEFF Research Database (Denmark)

    Shahnazari, Ali; Andersen, Mathias Neumann; Liu, Fulai

    2008-01-01

    Partial root zone drying (PRD) is a new water-saving irrigation strategy being tested in many crop species. Until now it has not been investigated in potatoes (Solanum tuberosum L.). A field experiment on sandy soil in Denmark was conducted under a mobile rainout shelter to study effects of two...... subsurface drip irrigation treatments ((1) Full Irrigation (FI) receiving 100% of evaporative demand; and (2) PRD receiving 70% water of FI) on potato yield, tuber size, leaf water relations and irrigation water use efficiency (IWUE). The PRD treatment was started just after the end of tuber initiation...

  17. Exploratory spatial data analysis of the distribution of regional per capita GDP in Yangtze Delta, China: 1994-2004

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Based on the spatial economy theory and the exploratory spatial data analysis (ESDA) technology, this paper studies the space-time dynamics of regional per capita GDP in the Yangtze Delta. A sample of 74 regions in the Yangtze Delta over the period of 1994 to 2004 provides clear evidence of global and local spatial autocorrelation as well as spatial heterogeneity in the distribution of regional per capita GDP The dynamism of regions is investigated by exploring the spatial pattern of regional growth, compared with that before 1997, the economic growth disparities among Shanghai, Zhejiang and Jiangsu provinces have decreased, so have the inside regions of Zhejiang Province, while it is opposite to the inside regions of Jiangsu Province.

  18. High resolution aerosol optical thickness retrieval over the Pearl River Delta region with improved aerosol modelling

    Institute of Scientific and Technical Information of China (English)

    WONG; ManSing; NICHOL; Janet; LEE; Kwon; Ho

    2009-01-01

    Aerosol retrieval algorithms for the MODerate Resolution Imaging Spectroradiometer (MODIS) have been developed to estimate aerosol and microphysical properties of the atmosphere, which help to address aerosol climatic issues at global scale. However, higher spatial resolution aerosol products for urban areas have not been well researched mainly due to the difficulty of differentiating aerosols from bright surfaces in urban areas. Here, a new aerosol retrieval algorithm using the MODIS 500 m resolution images is described, to retrieve aerosol properties over Hong Kong and the Pearl River Delta region. The rationale of our technique is to first estimate the aerosol reflectance by decomposing the top-of-atmosphere reflectance from surface reflectance and Rayleigh path reflectance. For the determination of surface reflectance, a modified Minimum Reflectance Technique (MRT) is used, and MRT images are computed for different seasons. A strong correlation is shown between the surface reflectance of MRT images and MODIS land surface reflectance products (MOD09), with a value of 0.9. For conversion of aerosol reflectance to Aerosol Optical Thickness (AOT), comprehensive Look Up Tables (LUT) are constructed, in which aerosol properties and sun-viewing geometry in the radiative transfer calculations are taken into account. Four aerosol types, namely mixed urban, polluted urban, dust, and heavy pollution, were derived using cluster analysis on three years of AERONET measurements in Hong Kong. Their aerosol properties were input for LUT calculation. The resulting 500 m AOT images are highly correlated (r = 0.89) with AERONET sunphotometer observations in Hong Kong. This study demonstrates the applicability of aerosol retrieval at fine resolution scale in urban areas, which can assist the study of aerosol loading distribution and the impact of localized and transient pollution on urban air quality. In addition, the MODIS 500 m AOT images can be used to study cross

  19. High resolution aerosol optical thickness retrieval over the Pearl River Delta region with improved aerosol modelling

    Institute of Scientific and Technical Information of China (English)

    WONG ManSing; NICHOL Janet; LEE Kwon Ho; LI ZhanQing

    2009-01-01

    Aerosol retrieval algorithms for the MODerate Resolution Imaging Spectroradiometer (MODIS) have been developed to estimate aerosol and microphysical properties of the atmosphere, which help to address aerosol climatic issues at global scale. However, higher spatial resolution aerosol products for urban areas have not been well researched mainly due to the difficulty of differentiating aerosols from bright surfaces in urban areas. Here, a new aerosol retrieval algorithm using the MODIS 500 m resolu-tion images is described, to retrieve aerosol properties over Hong Kong and the Pearl River Delta re-gion. The rationale of our technique is to first estimate the aerosol reflectance by decomposing the top-of-atmosphere reflectance from surface reflectance and Rayleigh path reflectance. For the deter-mination of surface reflectance, a modified Minimum Reflectance Technique (MRT) is used, and MRT images are computed for different seasons. A strong correlation is shown between the surface reflec-tance of MRT images and MODIS land surface reflectance products (MOD09), with a value of 0.9. For conversion of aerosol reflectance to Aerosol Optical Thickness (AOT), comprehensive Look Up Tables (LUT) are constructed, in which aerosol properties and sun-viewing geometry in the radiative transfer calculations are taken into account. Four aerosol types, namely mixed urban, polluted urban, dust, and heavy pollution, were derived using cluster analysis on three years of AERONET measurements in Hong Kong. Their aerosol properties were input for LUT calculation. The resulting 500 m AOT images are highly correlated (r=0.89) with AERONET sunphotometer observations in Hong Kong. This study demonstrates the applicability of aerosol retrieval at fine resolution scale in urban areas, which can assist the study of aerosol loading distribution and the impact of localized and transient pollution on urban air quality. In addition, the MODIS 500 m AOT images can be used to study cross

  20. Source apportionment and health effect of NOx over the Pearl River Delta region in southern China.

    Science.gov (United States)

    Lu, Xingcheng; Yao, Teng; Li, Ying; Fung, Jimmy C H; Lau, Alexis K H

    2016-05-01

    As one of the most notorious atmospheric pollutants, NOx not only promotes the formation of ozone but also has adverse health effects on humans. It is therefore of great importance to study the sources of NOx and its effects on human health. The Comprehensive Air Quality Model (CAMx) modeling system and ozone source apportionment technology (OSAT) were used to study the contribution of NOx from different emission sources over southern China. The results indicate that heavy duty diesel vehicles (HDDVs) and industrial point sources are the two major local NOx sources, accounting for 30.8% and 18.5% of local NOx sources, respectively. In Hong Kong, marine emissions contributed around 43.4% of local NOx in 2011. Regional transport is another important source of this pollutant, especially in February and November, and it can contribute over 30% of ambient NOx on average. Power plant point emission is an significant regional source in Zhuhai, Zhongshan and Foshan. The total emission sources are estimated to cause 2119 (0-4405) respiratory deaths and 991 (0-2281) lung cancer deaths due to long-term exposure to NOx in the Pearl River Delta region. Our results suggest that local governments should combine their efforts and vigorously promote further reduction of NOx emissions, especially for those sources that make a substantial contribution to NOx emissions and affect human health: HDDV, LDGV, industrial point sources and marine sources.

  1. The inhabited environment, infrastructure development and advanced urbanization in China’s Yangtze River Delta Region

    Science.gov (United States)

    Zhu, Xiaoqing; Gao, Weijun; Zhou, Nan; Kammen, Daniel M.; Wu, Yiqun; Zhang, Yao; Chen, Wei

    2016-12-01

    This paper analyzes the relationship among the inhabited environment, infrastructure development and environmental impacts in China’s heavily urbanized Yangtze River Delta region. Using primary human environment data for the period 2006-2014, we examine factors affecting the inhabited environment and infrastructure development: urban population, GDP, built-up area, energy consumption, waste emission, transportation, real estate and urban greenery. Then we empirically investigate the impact of advanced urbanization with consideration of cities’ differences. Results from this study show that the growth rate of the inhabited environment and infrastructure development is strongly influenced by regional development structure, functional orientations, traffic network and urban size and form. The effect of advanced urbanization is more significant in large and mid-size cities than huge and mega cities. Energy consumption, waste emission and real estate in large and mid-size cities developed at an unprecedented rate with the rapid increase of economy. However, urban development of huge and mega cities gradually tended to be saturated. The transition development in these cities improved the inhabited environment and ecological protection instead of the urban construction simply. To maintain a sustainable advanced urbanization process, policy implications included urban sprawl control polices, ecological development mechanisms and reforming the economic structure for huge and mega cities, and construct major cross-regional infrastructure, enhance the carrying capacity and improvement of energy efficiency and structure for large and mid-size cities.

  2. Vulnerabilities and Adapting Irrigated and Rainfed Cotton to Climate Change in the Lower Mississippi Delta Region

    Directory of Open Access Journals (Sweden)

    Saseendran S. Anapalli

    2016-10-01

    Full Text Available Anthropogenic activities continue to emit potential greenhouse gases (GHG into the atmosphere leading to a warmer climate over the earth. Predicting the impacts of climate change (CC on food and fiber production systems in the future is essential for devising adaptations to sustain production and environmental quality. We used the CSM-CROPGRO-cotton v4.6 module within the RZWQM2 model for predicting the possible impacts of CC on cotton (Gossypium hirsutum production systems in the lower Mississippi Delta (MS Delta region of the USA. The CC scenarios were based on an ensemble of climate projections of multiple GCMs (Global Climate Models/General Circulation Models for climate change under the CMIP5 (Climate Model Inter-comparison and Improvement Program 5 program, that were bias-corrected and spatially downscaled (BCSD at Stoneville location in the MS Delta for the years 2050 and 2080. Four Representative Concentration Pathways (RCP drove these CC projections: 2.6, 4.5, 6.0, and 8.5 (these numbers refer to radiative forcing levels in the atmosphere of 2.6, 4.5, 6.0, and 8.5 W·m−2, representing the increasing levels of the greenhouse gas (GHG emission scenarios for the future, as used in the Intergovernmental Panel on Climate Change-Fifth Assessment Report (IPCC-AR5. The cotton model within RZWQM2, calibrated and validated for simulating cotton production at Stoneville, was used for simulating production under these CC scenarios. Under irrigated conditions, cotton yields increased significantly under the CC scenarios driven by the low to moderate emission levels of RCP 2.6, 4.5, and 6.0 in years 2050 and 2080, but under the highest emission scenario of RCP 8.5, the cotton yield increased in 2050 but declined significantly in year 2080. Under rainfed conditions, the yield declined in both 2050 and 2080 under all four RCP scenarios; however, the yield still increased when enough rainfall was received to meet the water requirements of the crop (in

  3. Region-specific induction of deltaFosB by repeated administration of typical versus atypical antipsychotic drugs.

    Science.gov (United States)

    Atkins, J B; Chlan-Fourney, J; Nye, H E; Hiroi, N; Carlezon, W A; Nestler, E J

    1999-08-01

    Whereas acute administration of many types of stimuli induces c-Fos and related proteins in brain, recent work has shown that chronic perturbations cause the region-specific accumulation of novel Fos-like proteins of 35-37 kD. These proteins, termed chronic FRAs (Fos-related antigens), have recently been shown to be isoforms of DeltaFosB, which accumulate in brain due to their enhanced stability. In the present study, we sought to extend earlier findings that documented the effects of acute administration of antipsychotic drugs (APDs) on induction of Fos-like proteins by investigating the ability of typical and aytpical APDs, after chronic administration, to induce these DeltaFosB isoforms in several brain regions implicated in the clinical actions of these agents. By Western blotting we found that chronic administration of the typical APD, haloperidol, dramatically induces DeltaFosB in caudate-putamen (CP), a brain region associated with the extrapyramidal side effects of this drug. A smaller induction was seen in the nucleus accumbens (NAc) and prefrontal cortex (PFC), brain regions associated with the antipsychotic effects of the drug. In contrast, chronic administration of the prototype atypical APD clozapine failed to significantly increase levels of DeltaFosB in any of the three brain regions, and even tended to reduce DeltaFosB levels in the NAc. Two putative atypical APDs, risperidone and olanzapine, produced small but still significant increases in the levels of DeltaFosB in CP, but not NAc or PFC. Studies with selective receptor antagonists suggested that induction of DeltaFosB in CP and NAc is most dependent on antagonism of D2-D3 dopamine receptors, with antagonism of D1-like receptors most involved in the PFC. Immunohistochemical analysis confirmed the greater induction of DeltaFosB in CP by typical versus atypical APDs, with no significant induction seen in PFC with either class of APD. Together, these findings demonstrate that repeated administration

  4. A Tale of Two Deltas: Contrasting Perspectives on the State of Natural and Human-modified Regions of the Ganges-Brahmaputra River Delta (Invited)

    Science.gov (United States)

    Goodbred, S. L.; Wallace Auerbach, L.; Wilson, C.; Gilligan, J. M.; Roy, K.; Ahmed, K.; Steckler, M. S.; Seeber, L.; Akhter, S. H.; Hossain, S.

    2013-12-01

    Effective risk analysis and the management of complex coastal systems require that the scale of interest be well defined. Here we present recent research from the Ganges-Brahmaputra river delta (GBD) that highlights different, if not divergent, perspectives on the current status of this system and its potential response to future environmental change. The contrasts emerge from viewing the GBD at different temporal and spatial scales, raising the question of how scientists, stakeholders, and decision makers might most effectively develop a shared understanding of large, at-risk delta systems. Among the world's deltas, the GBD is often cited as being highly vulnerable to future sea-level rise and environmental change, owing to its vast low-lying landscape and large human population. Taking a broad perspective, however, it is not coincident that the GBD, the world's largest delta system, is fed by immense water and sediment discharge from the Asian monsoon and Himalayan orogen - simply, the size of the GBD reflects the robust processes that have constructed and maintained it. At the regional scale, the deltaplain itself is interconnected by a labyrinth of fluvial and tidal channels that effectively convey sediment to most areas of the landscape, through overbank flooding, distributaries, and tidal transport. Together, the sediment supply, water discharge, and dense channel network bless the GBD with potential basinwide accretion rates >5 mm/yr. More locally, modern sedimentation rates >10 mm/yr are observed in many areas of the tidal delta plain, which are sufficient to maintain land-surface elevations under a variety of sea-level rise scenarios, or at least to mitigate whatever effects do occur. The long-term stratigraphic record of the GBD also reflects a system in dynamic equilibrium, with major landforms persisting through changes in sea level, sediment loading, river avulsion, and delta lobe switching - together providing an encouraging outlook in the face of

  5. Morphological change in the Pearl River Delta, China

    NARCIS (Netherlands)

    Zhang, W.; Xu, Y.; Hoitink, A.J.F.; Sassi, M.G.; Zheng, J.; Chen, X.; Zhang, C.

    2015-01-01

    Morphological changes in the Pearl River Delta (PRD) have been investigated using bathymetric charts, underwater Digital Elevation Models, remote sensing data and Geographic Information Systems. Water depths were extracted from digitized charts to explore the accretion–erosion characteristics of thr

  6. Finding attractive markets for the educational programs of the Energy Delta Institute (EDI) : Market research in three European regions

    NARCIS (Netherlands)

    Meijerhof, Jos

    2005-01-01

    The Energy Delta Institute, a provider of courses on many subjects related to natural gas, wants to know the market potential of the different national natural gas markets and market players in three European regions. This research uses data about thirty-nine national natural gas markets to make a

  7. Finding attractive markets for the educational programs of the Energy Delta Institute (EDI) : Market research in three European regions

    NARCIS (Netherlands)

    Meijerhof, Jos

    2005-01-01

    The Energy Delta Institute, a provider of courses on many subjects related to natural gas, wants to know the market potential of the different national natural gas markets and market players in three European regions. This research uses data about thirty-nine national natural gas markets to make a r

  8. Analysis of energetic radiation associated with thunderstorms in the Ebro delta region in Spain

    Science.gov (United States)

    Fabró, Ferran; Montanyà, Joan; Pineda, Nicolau; Argemí, Oriol; Velde, Oscar A.; Romero, David; Soula, Serge

    2016-08-01

    The analysis of high-energy background radiation (0.1-2 MeV) enhancements during eight winter thunderstorms and five summer storms in the Ebro delta region in the northeast of Spain is presented. For the first time, high-energy radiation counts, precipitation, radar reflectivity, and very high frequency lightning detections to infer charge regions altitude have been analyzed in order to find out what produces the measured background radiation increments associated with storms. The good agreement between radar reflectivity and precipitation with increases in background radiation counts coupled with the spectrum analysis comparing rain/no rain periods suggests that radon-ion daughters play a major role in the radiation increments reported. No evidence has been found supporting that measured background radiation enhancements can be produced by storm electric fields. Finally, a single case of a high-energy radiation increase was prior to a cloud-to-ground lightning stroke, which reinforces the theory that a lower positive charge layer's existence is important for the production of Terrestrial Ground Enhancements.

  9. RETRIEVAL OF MINERAL ABUNDANCES OF THE DELTA REGION IN EBERSWALDE, MARS

    Directory of Open Access Journals (Sweden)

    X. Wu

    2017-07-01

    Full Text Available Eberswalde Crater, a hotspot of Mars exploration, possesses an unambiguous hydrological system. However, little research has been performed on the large-scale mineral abundances retrieval in this region. Hence, we employed hyperspectral unmixing technology to quantitatively retrieve mineral abundances of the delta region in Eberswalde. In this paper, the single-scattering albedos were calculated by the Hapke bidirectional reflectance function from Compact Reconnaissance Imaging Spectrometer for Mars (CRISM data (FRT000060DD and CRISM spectral library respectively, and a sparse unmixing algorithm was adopted to quantitatively retrieve mineral abundances. The abundance maps show that there are six kinds of minerals (pyroxene, olivine, plagioclase, siderite, diaspore, and tremolite. By comparing minerals spectra obtained from images with corresponding spectra in spectral library, we found the similar trend in both curves. Besides, the mineral abundance maps derived in this study agree well spatially with CRISM parameter maps. From the perspective of mineralogy, the instability of pyroxene and olivine indicates the area in which they distribute is close to provenance, and the original provenance is ultrabasic rock (e.g. peridotite and basic rock (e.g. gabbro, respectively. And minerals, existing in the area of alluvial fan, also distribute in the outside of alluvial fan, which might be caused by fluid transportation.

  10. Emergy Synthesis and Regional Sustainability Assessment: Case Study of Pan-Pearl River Delta in China

    Directory of Open Access Journals (Sweden)

    Guomin Li

    2014-08-01

    Full Text Available In this paper, emergy analysis is used in association with the ternary diagrams and geographic information system (GIS tools to improve the evaluation of sustainability for the Pan-Pearl River Delta (PPRD region. Emergy accounting of PPRD is estimated, and various emergy-based indicators are reported. Ternary diagrams are drawn to provide a graphical representation of the emergy accounting data. Finally, the GIS tools are employed to assist in the emergy-based spatial analysis, and emergy density based on flat land area is mapped to reflect the intensity of emergy use in human activity areas. Results show the following: (1 the current development path of the PPRD region, with the value of emergy sustainability index (ESI = 0.227 significantly lower than one, is unsustainable in the long run; (2 Guangdong has the lowest ESI value (0.071, and the ESI values of Fujian, Guangxi, Hunan and Jiangxi are lower than 0.5, indicating that the economy in these provinces overly relies on non-renewable and imported resources; (3 Guizhou has a high emergy yield rate and is thus the main energy supplier in PPRD; and (4 among the nine provinces in PPRD, only Hainan has an ESI value (2.145 higher than one.

  11. Emission inventory of anthropogenic air pollutants and VOC species in the Yangtze River Delta region, China

    Directory of Open Access Journals (Sweden)

    C. Huang

    2011-05-01

    Full Text Available The purpose of this study is to develop an emission inventory for major anthropogenic air pollutants and VOC species in the Yangtze River Delta (YRD region for the year 2007. A "bottom-up" methodology was adopted to compile the inventory based on major emission sources in the sixteen cities of this region. Results show that the emissions of SO2, NOx, CO, PM10, PM2.5, VOCs, and NH3 in the YRD region for the year 2007 are 2392 kt, 2293 kt, 6697 kt, 3116 kt, 1511 kt, 2767 kt, and 459 kt, respectively. Ethylene, mp-xylene, o-xylene, toluene, 1,2,4-trimethylbenzene, 2,4-dimethylpentane, ethyl benzene, propylene, 1-pentene, and isoprene are the key species contributing 77 % to the total ozone formation potential (OFP. The spatial distribution of the emissions shows the emissions and OFPs are mainly concentrated in the urban and industrial areas along the Yangtze River and around Hangzhou Bay. The industrial sources, including power plants other fuel combustion facilities, and non-combustion processes contribute about 97 %, 86 %, 89 %, 91 %, and 69 % of the total SO2, NOx, PM10, PM2.5, and VOC emissions. Vehicles take up 12.3 % and 12.4 % of the NOx and VOC emissions, respectively. Regarding OFPs, the chemical industry, domestic use of paint & printing, and gasoline vehicles contribute 38 %, 24 %, and 12 % to the ozone formation in the YRD region.

  12. 珠三角地区2009-2013年男男性行为者HIV感染率及其影响因素分析%Prevalence of human immunodeficiency virus and associated risk factors among men who have sex with men in the major regions of Pearl River Delta, from 2009 to 2013

    Institute of Scientific and Technical Information of China (English)

    龙其穗; 林鹏; 李艳; 付笑冰; 刘珺; 叶荣; 李杰; 黄惠珍

    2014-01-01

    Objective To examine the HIV prevalence and associated risk factors among men who have sex with men (MSM) in the Pearl River Delta (PRD) region,in order to provide scientific basis for assessment on HIV prevention programs.Methods Surveillance projects on HIV infection status and risk factors were carried out among MSM in six prefectural PRD cities,based on the national sentinel surveillance program among MSM.Results A total of 8 770 MSM were recruited in the six PRD prefectural cities from 2009 to 2013.The overall prevalence rates of HIV among MSM during 2009 and 2013 were 4.7%,9.7%,10.6%,12.9% and 11.4%,respectively,appeared an increasing trend.HIV related high-risk behaviors were commonly seen among MSM.The proportion of consistent condom use during anal sex in the last six months was 46.3%.Associated risk factors for HIV infection among MSM would include older age,being non-permenant residents,inconsistent condom use,history of having had sexually transmitted diseases and without having received intervention services in the last year.Conclusion High-risk behaviors were popular in the MSM population that causing the HIV transmission to expand among the MSM population in the major region of PRD.It seemed necessary to reinforce the publicity and education programs as well as effective behavior intervening measures among the MSM group.%目的 了解珠三角地区MSM的HIV感染状况及其影响因素.方法 2009-2013年采用全国MSM哨点监测方案调查该地区内6市MSM的HIV感染率,并分析影响因素.结果 2009-2013年珠三角地区6市共调查MSM 8 770例,HIV感染率分别为4.7%、9.7%、10.6%、12.9%和11.4%,呈上升趋势.MSM中危险行为较为普遍,最近6个月肛交每次使用安全套的比例为46.3%.年龄较大、外省籍、不坚持使用安全套、1年内被诊断患过性病及1年内未接受过艾滋病相关干预服务,是该人群感染HIV的危险因素.结论 珠三角地区MSM中HIV传播危

  13. A regional coupled surface water/groundwater model of the Okavango Delta, Botswana

    DEFF Research Database (Denmark)

    Bauer-Gottwein, Peter; Gumbricht, T.; Kinzelbach, W.

    2006-01-01

    consumed by evapotranspiration. With an approximate size of about 30,000 km(2), the Okavango Delta is the world's largest site protected under the convention on wetlands of international importance, signed in 1971 in Ramsar, Iran. The extended wetlands of the Okavango Delta, which sustain a rich ecology...

  14. Temporal fluctuation of multidrug resistant salmonella typhi haplotypes in the mekong river delta region of Vietnam.

    Directory of Open Access Journals (Sweden)

    Kathryn E Holt

    Full Text Available BACKGROUND: typhoid fever remains a public health problem in Vietnam, with a significant burden in the Mekong River delta region. Typhoid fever is caused by the bacterial pathogen Salmonella enterica serovar Typhi (S. Typhi, which is frequently multidrug resistant with reduced susceptibility to fluoroquinolone-based drugs, the first choice for the treatment of typhoid fever. We used a GoldenGate (Illumina assay to type 1,500 single nucleotide polymorphisms (SNPs and analyse the genetic variation of S. Typhi isolated from 267 typhoid fever patients in the Mekong delta region participating in a randomized trial conducted between 2004 and 2005. PRINCIPAL FINDINGS: the population of S. Typhi circulating during the study was highly clonal, with 91% of isolates belonging to a single clonal complex of the S. Typhi H58 haplogroup. The patterns of disease were consistent with the presence of an endemic haplotype H58-C and a localised outbreak of S. Typhi haplotype H58-E2 in 2004. H58-E2-associated typhoid fever cases exhibited evidence of significant geo-spatial clustering along the Sông H u branch of the Mekong River. Multidrug resistance was common in the established clone H58-C but not in the outbreak clone H58-E2, however all H58 S. Typhi were nalidixic acid resistant and carried a Ser83Phe amino acid substitution in the gyrA gene. SIGNIFICANCE: the H58 haplogroup dominates S. Typhi populations in other endemic areas, but the population described here was more homogeneous than previously examined populations, and the dominant clonal complex (H58-C, -E1, -E2 observed in this study has not been detected outside Vietnam. IncHI1 plasmid-bearing S. Typhi H58-C was endemic during the study period whilst H58-E2, which rarely carried the plasmid, was only transient, suggesting a selective advantage for the plasmid. These data add insight into the outbreak dynamics and local molecular epidemiology of S. Typhi in southern Vietnam.

  15. Multi-wavelength study of a delta-spot I: A region of very strong, horizontal magnetic field

    CERN Document Server

    Jaeggli, Sarah A

    2015-01-01

    Active region NOAA 11035 appeared in December 2009, early in the new solar activity cycle. This region achieved a delta sunspot ($\\delta$-spot) configuration when parasitic flux emerged near the rotationally leading magnetic polarity and traveled through the penumbra of the largest sunspot in the group. Both visible and infrared imaging spectropolarimetry of the magnetically sensitive Fe I line pairs at 6302 \\AA\\ and 15650 \\AA\\ show large Zeeman splitting in the penumbra between the parasitic umbra and the main sunspot umbra. The polarized Stokes spectra in the strongest field region display anomalous profiles, and strong blueshifts are seen in an adjacent region. Analysis of the profiles is carried out using a Milne-Eddington inversion code capable of fitting either a single magnetic component with stray light or two independent magnetic components to verify the field strength. The inversion results show that the anomalous profiles cannot be produced by the combination of two profiles with moderate magnetic ...

  16. Tooth Loss in Appalachia and the Mississippi Delta Relative to Other Regions in the United States, 1999–2010

    Science.gov (United States)

    Gorsuch, Marina Mileo; Sanders, Seth G.; Wu, Bei

    2014-01-01

    Objectives. We examined regional variation in tooth loss in the United States from 1999 to 2010. Methods. We used 6 waves of the Behavioral Risk Factor Surveillance System and data on county characteristics to describe regional trends in tooth loss and decompose diverging trends into the parts explained by individual and county components. Results. Appalachia and the Mississippi Delta had higher levels of tooth loss than the rest of the country in 1999. From 1999 to 2010, tooth loss declined in the United States. However, Appalachia did not converge toward the US average, and the Mississippi Delta worsened relative to the United States. Socioeconomic status explained the largest portion of differences between regions in 1999, but a smaller portion of the trends. The Mississippi Delta is aging more quickly than the rest of the country, which explains 17% of the disparity in the time trend. Conclusions. The disadvantage in tooth loss is persistent in Appalachia and growing in the Mississippi Delta. The increasing disparity is partly explained by changes in the age structure but is also associated with behavioral and environmental factors. PMID:24524527

  17. Performance of PRD Welled Surfaces in T Shape Noise Barriers for Controlling Environmental Noise

    Directory of Open Access Journals (Sweden)

    S Momen Bellah

    2010-07-01

    Full Text Available "n "n "nBackgrounds and Objectives: There is a considerable notice in the use of noise barriers in recent years. Noise barriers as a control noise solution can increase the insertion loss to protect receivers. This paper presents the results of an investigation about the acoustic efficiency of primitive root sequence diffuser (PRD on environmental single T-shape barrier."nMaterials and Methods: A 2D boundary element method (BEM is used to predict the insertion loss of the tested barriers. The results of rigid and with quadratic residue diffuser (QRD coverage are also predicted for comparison."nResults: It is found that decreasing the design frequency of PRD shifts the frequency effects towards lower frequencies, and therefore the overall A-weighted insertion loss is improved. It is also found that using wire mesh with reasonably efficient resistivity on the top surface of PRD improves the efficiency of the reactive barriers; however utilizing wire meshes with flow resistivity higher than specific acoustic impedance of air on the PRD top of a diffuser barrier significantly reduces the performance of the barrier within the frequency bandwidth of the diffuser. The performance of PRD covered T-shape barrier at 200 Hz was found to be higher than that of its equivalent QRD barriers in both the far field and areas close to the ground. The amount of improvement compared made by PRD barrier compared with its equivalent rigid barrier at far field is about 2 to 3 dB, while this improvement relative to barrier model .QR4. can reach up to 4- 6 dB."nConclusion: Employing PRD on the top surface of T-shape barrier is found to improve the performance of barriers compared with using rigid and QRD coverage at the examined receiver locations.

  18. Suspended sediment transport in distributary channel networks and its implication on the evolution of delta

    Science.gov (United States)

    Suying, Ou; hao, Yang

    2016-04-01

    Suspended sediment (SS) transport in distributary channels play an important role on the evolution of deltas and estuaries. Under the interactions between river discharge, tide, and bathymetry of Pearl River delta (PRD) in south China, the spatial and temporal characteristics of suspended sediment transport are investigated by using the field data of July 16 to 25, 1999 and February 7 to 15, 2001. The PRD, as one of the most complex tributary system in the world and composed of 324 transversal and longitudinal tributaries, with eight outlets to the three sub-estuaries, has higher suspended sediment load in middle delta including six outlets than in right and left tidal dominant channels of PRD, that is Humen channel and Yamen channel system. Under large river discharge of one flood in summer, the tidal averaged SS transport from channel to the estuaries, the SS concentration of middle delta is 10~20 times and the transport rate is 100~500 times of dry season. But the transport rate changes little between flood season and dry season in the upper channel system of Yamen and Humen, and in dry season the tidal averaged transport change direction from estuary to these channel systems. About 70~85% of total Pearl River SS load transport along the main channel of West River, then transport about 45~55% into the lower West river delta, about 30% of total SS load flushed into the Modaomen outlets. Under the bathymetry of branched channels, SS load which advected from the Pearl River and resuspended from bed, redistributed 4~8 times in the PRD and then cause the different changes of channels. It found that in flood season, the suspended sediment load from Pearl River including East, West, North River and Tanjiang, Liuxi River into the PRD is less than that discharged into the estuaries through eight outlets, which indicated the erosion in the channels of PRD especially in the lower part of PRD. Suspended sediment budget in dry season during neap-spring cycle indicated that

  19. SPATIAL AND SEASONAL DISTRIBUTIONS OF ATMOSPHERIC CARBONACEOUS AEROSOLS IN PEARL RIVER DELTA REGION, CHINA

    Institute of Scientific and Technical Information of China (English)

    Junji Cao; Shuncheng Lee; Kinfai Ho; Shichun Zou; Xiaoye Zhang; Jianguo Pan

    2003-01-01

    Concentrations and spatial distributions of organic carbon (OC) and elemental carbon (EC) in atmospheric particles were measured at 8 sites in four cities (Hong Kong, Guangzhou, Shenzhen and Zhuhai) of Pearl River Delta Region (PRDR), China during 2001 winter period and 2002 summer period. PM2.5 (particle diameter smaller than 2.5μm)and PM10 (particle diameter smaller than 10 μm) samples were collected on pre-fired quartz filters with mini-volume samplers and analyzed using thermal optical reflectance (TOR) method. The average PM2.5 and PM10 level were 60.1naceous aerosol accounted for 37.8% of the PM2.5 and 32.8% of the PM10. The highest concentrations of OC and EC were observed at Guangzhou city in both winter and summer seasons. The average OC/EC ratios were 2.4 for PM2.5and 2.5 for PM10, indicating the presence of secondary organic aerosols. The OC and EC in PRDR were found to be strongly correlated (correlation coefficients >0.6), which implied that similar emission source contribute to the ambient carbon particles.

  20. Impact of Regional Economy on Internal Migration in Yangtze Delta: Based on Panel Data

    Institute of Scientific and Technical Information of China (English)

    Zhang Yina; Ren Yuan

    2007-01-01

    Metropolitan Shanghai,in Yangtze River Delta(YRD),plays undoubtedly the leading role in the economic development in China,and becomes one of the most important population congregation areas.It is also widely regarded as the sixth uprising urban agglomeration in the world.Based on the quantitative studies on basic socioeconomic and demographic profile on the number and transition of population,this paper concluded that the migration is the key factor for population dynamies in YRD.Then,what are the regional economic factors affecting the migration of different cities in YRD? The panel data show that the different wage level is the most important factor that affects the immigration in YRD.Moreover,the ratio of industry sector and service sector has an impact on attracting immigration.However,per-capital GDP and the share of foreign direct investment(FDI)to GDP have dual-side impact:not high per-capital GDP and FDI bring the high immigration.

  1. Total gaseous mercury in Pearl River Delta region, China during 2008 winter period

    Science.gov (United States)

    Li, Zheng; Xia, Chonghuan; Wang, Xinming; Xiang, Yunrong; Xie, Zhouqing

    2011-02-01

    Total gaseous mercury (TGM) was monitored at Wanqingsha, a rural site in the central Pearl River Delta region, south China from 23 November to 22 December, 2008. TGM ranged 0.50-18.67 ng m -3 with an average of 2.94 ng m -3. TGM was found to present a diurnal cycle with the maximum at 7:00-8:00 and the minimum at 14:00-16:00 (local time). The afternoon minimum in TGM were likely related to increased vertical mixing and the TGM oxidation by ozone, which was observed to negative correlation with TGM. A sudden increase in TGM from 6:00-7:00 could be due to activation of local surface emission sources by rising air temperature. Similar variations in TGM and trace gases including CO and SO 2 suggested potential anthropogenic sources contribution as well. Wind-rose patterns further indicated that the westerly wind might carry high concentration of TGM from the high mercury emission areas of Southwest China and/or local anthropogenic emission sources.

  2. Black cloud and transport of anthropogenic pollution across the Mediterranean Sea over Nile Delta region in Egypt during Fall season

    Science.gov (United States)

    El-Askary, H. M.; Prasad, A. K.; Kafatos, M.

    2010-12-01

    The Nile River Delta is the most populous region of Egypt with major agricultural and industrial activities. The region suffers from intense episodes of natural and anthropogenic pollution especially during Spring (March-April-May), Summer (June-July-August), Fall (September-October-November), and Winter (December-January-February) seasons. Previous studies found that the summer season shows long range transport of pollutants from Europe which is widely accepted. Recent studies attribute the local biomass burning in open fields to be the major culprit behind increased levels of pollution over major cities of the Delta region (such as Cairo) especially during the Fall season. Such episodes result in dense fog and haze which is locally known as "Black Cloud". We have analyzed multiple satellite datasets such as Moderate Resolution Imaging Spectroradiometer (MODIS) higher resolution aerosol parameters, vertical profiles from AIRS (meteorological and other parameters), Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT), Goddard Chemistry Aerosol Radiation and Transport (GOCART) Model, and ground collected data (AOD, PM10, SO2 and NO2) to study the cause of Fall-time pollution over the Delta region. We show that the major episodes of pollution, even during Fall season, is attributed to the inter-continental transport of pollution especially across the Mediterranean. The back-trajectories from HYSPLIT model and satellite data clearly show the source of the plume visible in the MODIS data. We have computed month-to-month mean of the back-trajectories during Fall season (2004-2009) and classified the back trajectories using available ground data to identify major sources of pollution during Fall. The vertical profile of the atmosphere from AIRS shows arrival of plume from northern regions affecting the air quality over all the major cities of the Delta region. Similar analysis can be applied to major population centers in the Indo-Gangetic region in

  3. Analysis the Opportunities and Challenges of Pearl River Delta Economy in China

    Institute of Scientific and Technical Information of China (English)

    陈铁双

    2014-01-01

    This paper examines the strategies of Chinese government policies to develop of Pearl River Delta (PRD) in the coming decades. Through analyzing the opportunities and chal enges of the Macro-environment of the PRD, I wil il ustrate the competition to be an investment basement from inside and outside of the country as wel as the supportive government policies. In the past three decades, the original core competences of PRD such as low labor cost, broad foreign investment policies and the even cheap transportation is losing its at ractiveness compared to the Yangtze River Delta (YRD). This paper also il ustrated the polices which support PRD economic transformation and Hong Kong as an international trade hub city that wil play a key role in enhancing the speed of the transformation. The expectation of this research is that PRD wil present itself as a new economic zone in the world, develop value-added, high-tech manufacturing, brand innovated, and environment friendly industries. A new outlook of PRD is emerging in front of the world.

  4. Oil, gender and agricultural child labour in the Niger Delta region of ...

    African Journals Online (AJOL)

    ... violent conflicts, crimes, rural-urban migration, environmental degradation, ... The relationship between household size and agricultural child labour and ... Keywords: Gender, Agricultural child labour, Niger Delta, Poverty, Oil, Multinationals.

  5. Morphological changes at Godavari delta region due to waves, currents and the associated physical processes

    Digital Repository Service at National Institute of Oceanography (India)

    Sastry, J.S.; Vethamony, P.; Swamy, G.N.

    the speed of 200 cm/sec. The morphological changes due to the effect of river discharge during various seasons and the development of Godavari sand spit off Kakinada and its influence to delta modification are detailed....

  6. Spatiotemporal change of ecological footprint and sustainability analysis for Yangtze Delta Region

    Institute of Scientific and Technical Information of China (English)

    WANG Ping; WANG Xinjun

    2011-01-01

    In the urbanizing world,the Yangtze Delta Region (YDR) as one of the most developed regions in China,has drawn a lot of the world's attention for the remarkable economic development achieved in the past decades.Nevertheless,the rapid economic development was certain to be accompanied by unprecedented consumption and loss of natural resources.Therefore,the analysis of the ecological situation and driving factors of environmental impact was of great significance to serve the local sustainable development decision-making and build a harmonious society.In this paper,the ecological footprint (EF) was taken as the index of the ecological environmental impact.With the help of Geographic Information System (GIS),we studied the spatiotemporal change of ecological footprint at two scales (region and city) and assessed urban sustainable development ability in YDR.Then we discussed the driving factors that affected the change of ecological footprint by the Stochastic Impacts by Regression on Population,Affluence,and Technology (STIRPAT) model.The results showed that increasing trends of regional ecological footprint during 1998-2008 (1.70-2.53 ha/cap) were accompanied by decreasing ecological capacity (0.31-0.25 ha/cap) but expanding ecological deficit (1.39-2.28 ha/cap).The distribution pattern of ecological footprint and the degree of sustainable development varied distinctly from city to city in YDR.In 2008,the highest values of ecological footprint (3.85 ha/cap) and the lowest one of sustainable development index (SDI=1) in YDR were both presented in Shanghai.GDP per capita (A) was the most dominant driving force of EF and the classical EKC hypothesis did not exist between A and EF in 1998-2008.Consequently,increasing in ecological supply and reducing in human demand due to technological advances or other factors were one of the most effective ways to promote sustainable development in YDR.Moreover,importance should be attached to change our definition and measurement of

  7. Characterization of submicron aerosols at a rural site in Pearl River Delta of China using an Aerodyne High-Resolution Aerosol Mass Spectrometer

    Directory of Open Access Journals (Sweden)

    X.-F. Huang

    2010-11-01

    Full Text Available The Pearl River Delta (PRD region in South China is one of the most economically developed regions in China, but it is also noted for its severe air pollution due to industrial/metropolitan emissions. In order to continuously improve the understanding and quantification of air pollution in this region, an intensive campaign was executed in PRD during October–November 2008. Here, we report and analyze Aerodyne High-Resolution Aerosol Mass Spectrometer measurements at Kaiping, a rural site downwind of the highly-polluted central PRD area, to characterize the general features of submicron particulate pollution in the regional air. The mean measured PM1 mass concentration was 33.1 ± 18.1 μg m−3 during the campaign and composed of organic matter (33.8%, sulfate (33.7%, ammonium (14.0%, nitrate (10.7%, black carbon (6.7%, and chloride (1.1%, which is characterized by high fractions of inorganic ions due to huge emissions of SO2 and NOx in PRD. The average size distributions of the species (except BC were all dominated by an accumulation mode peaking at ~450 nm in vacuum aerodynamic diameter. Calculations based on high-resolution organic mass spectra indicate that C, H, O, and N on average contributed 56.6, 7.0, 35.1, and 1.3% to the total organic mass, respectively, corresponding to an organic matter mass to organic carbon mass ratio (OM/OC of 1.77 ± 0.08. Based on the high-resolution organic mass spectral dataset observed, Positive Matrix Factorization (PMF analysis differentiated the organic aerosol into three components, i.e., biomass burning (BBOA and two oxygenated (LV-OOA and SV-OOA organic aerosols, which on average accounted for 24.5, 39.6 and 35.8% of the total organic mass, respectively. The BBOA showed strong features of biomass burning emissions and has been mainly attributed to field rice straw burning after harvest. The LV-OOA and SV-OOA were found to correspond to more aged (and thus

  8. Heavy metal pollution in surface soils of Pearl River Delta, China.

    Science.gov (United States)

    Jinmei, Bai; Xueping, Liu

    2014-12-01

    Heavy metal pollution is an increasing environmental problem in Chinese regions undergoing rapid economic and industrial development, such as the Pearl River Delta (PRD), southern China. We determined heavy metal concentrations in surface soils from the PRD. The soils were polluted with heavy metals, as defined by the Chinese soil quality standard grade II criteria. The degree of pollution decreased in the order Cd > Cu > Ni > Zn > As > Cr > Hg > Pb. The degree of heavy metal pollution by land use decreased in the order waste treatment plants (WP) > urban land (UL) > manufacturing industries (MI) > agricultural land (AL) > woodland (WL) > water sources (WS). Pollution with some of the metals, including Cd, Cu, Ni, and Zn, was attributed to the recent rapid development of the electronics and electroplating industries. Cd, Hg, and Pb (especially Cd) pose high potential ecological risks in all of the zones studied. The soils posing significantly high and high potential ecological risks from Cd covered 73.3 % of UL, 50 % of MI and WP land, and 48.5 % of AL. The potential ecological risks from heavy metals by land use decreased in the order UL > MI > AL > WP > WL > WS. The control of Cd, Hg, and Pb should be prioritized in the PRD, and emissions in wastewater, residue, and gas discharges from the electronics and electroplating industry should be decreased urgently. The use of chemical fertilizers and pesticides should also be decreased.

  9. Technology targeting for sustainable intensification of crop production in the Delta region of Bangladesh

    Science.gov (United States)

    Schulthess, U.; Krupnik, T. J.; Ahmed, Z. U.; McDonald, A. J.

    2015-04-01

    Remote sensing data are nowadays being acquired within short intervals and made available at a low cost or for free. This opens up opportunities for new remote sensing applications, such as the characterization of entire regions to identify most suitable areas for technology targeting. Increasing population growth and changing dietary habits in South Asia call for higher cereal production to ensure future food security. In the Delta area of Bangladesh, surface water is considered to be available in quantities large enough to support intensification by adding an irrigated dry season crop. Fuel-efficient, low lift axial flow pumps have shown to be suitable to carry water to fields that are within a buffer of four hundred meters of the rivers. However, information on how and where to target surface water irrigation efforts is currently lacking. We describe the opportunities and constraints encountered in developing a procedure to identify cropland for which axial flow pumps could be successfully deployed upon in a 43'000 km2 area. First, we isolated cropland and waterways using Landsat 5 and 7 scenes using image segmentation followed by classification with the random forest algorithm. Based on Landsat 7 and 8 scenes, we extracted maximum dry season enhanced vegetation index (EVI) values, which we classified into fallow, low-, and high-intensity cropland for the last three years. Last, we investigated the potential for surface water irrigation on fallow and low-intensity land by applying a cropping risk matrix to address the twin threats of soil and water salinity. Our analysis indicates that there are at least 20,000 ha of fallow land under the low-risk category, while more than 100,000 ha of low-intensity cropland can be brought into intensified production. This information will aid in technology targeting for the efficient deployment of surface water irrigation as a tool for intensification.

  10. Gender and High School Organization: Insights on Leadership Styles in the Niger Delta Region

    Directory of Open Access Journals (Sweden)

    Jacinta A. Opara

    2011-06-01

    Full Text Available The position of the school principal as a leader is incontrovertible. The problems that plagues the school system are so numerous that those who are within the educational system are so overwhelmed not to talk of outsiders who are poised to ask such a pertinent question like “are the principals leading the schools well?” If the principals among the male and female are sophisticated with the theories and practice of management, to what extent do they quantitatively involve the rightful leadership styles to direct the affairs of their various schools? The sex of the principal has equally become very important in a study of this nature. Every person within the school system looks forward to the principals to give the appropriate leadership for others to follow. The sex of the principal from previous experience reveals that the strength of character and dynamism is needed to achieve or reach some administrative goals.The female principals may be intimidated by the enormity of the school problems and get carried away or accept the situation as it is. This study examined the quality valuation among the male and female principals in their choice of leadership styles in Rivers State of the Niger Delta region. The principals, the teachers and the student were all required to make their contributions to ascertain what style of leadership that is commonly adopted by the male on the one hand and the female principals on the other. The analysed data shows that the female principals qualitatively involve the democratic style of leadership than the men. The female principals also involve their staff in decision-making than does the male counterpart, the male principals, who adopted the democratic and the autocratic styles of leadership are quicker at the management of crises in schools than the female principals.

  11. Radiative {pi}{sup 0} photoproduction on protons in the {delta}{sup +} (1232) region

    Energy Technology Data Exchange (ETDEWEB)

    Schumann, S.; Beck, R.; Lang, M.; Nikolaev, A.; Unverzagt, M. [Johannes Gutenberg-Univ. Mainz, Inst. fuer Kernphysik, Mainz (Germany); Rheinische Friedrich-Wilhelms-Univ. Bonn, Helmholtz-Inst. fuer Strahlen- und Kernphysik, Bonn (Germany); Boillat, B.; Krusche, B.; Zehr, F. [Univ. Basel, Inst. fuer Physik, Basel (Switzerland); Downie, E.J. [Johannes Gutenberg-Univ. Mainz, Inst. fuer Kernphysik, Mainz (Germany); Univ. of Glasgow, Dept. of Physics and Astronomy, Glasgow (United Kingdom); Aguar-Bartolome, P.; Ahrens, J.; Arends, H.J.; Heid, E.; Jahn, O.; Krambrich, D.; Martinez-Fabregate, M.; Ostrick, M.; Rost, M.; Thomas, A.; Walcher, T. [Johannes Gutenberg-Univ. Mainz, Inst. fuer Kernphysik, Mainz (Germany); Annand, J.R.M.; Codling, R.; Livingston, K.; MacGregor, I.J.D.; McGeorge, J.C.; Owens, R.O.; Rosner, G. [Univ. of Glasgow, Dept. of Physics and Astronomy, Glasgow (United Kingdom); Bekrenev, V. [Petersburg Nuclear Physics Inst., Gatchina (Russian Federation); Braghieri, A.; Pedroni, P.; Rostomyan, T. [INFN Sezione di Pavia, Pavia (Italy); Branford, D.; Glazier, D.I.; Tarbert, C.M.; Watts, D.P. [Univ. of Edinburgh, School of Physics, Edinburgh (United Kingdom); Briscoe, W.J. [George Washington Univ., Center for Nuclear Studies, Washington, D.C. (United States); Brudvik, J.W.; Nefkens, B.M.K.; Prakhov, S.N.; Price, J.W.; Starostin, A. [Univ. of California at Los Angeles, CA (United States); Cherepnya, S.; Fil' kov, L.V.; Kashevarov, V.L. [Lebedev Physical Inst., Moscow (Russian Federation); Drexler, P.; Gregor, R.; Kotulla, M.; Lugert, S.; Metag, V.; Novotny, R. [Justus Liebig-Univ. Giessen, II. Physikalisches Inst., Giessen (Germany); Hornidge, D. [Mount Allison Univ., Sackville, NB (Canada); Kondratiev, R.; Lisin, V.; Polonski, A. [Inst. for Nuclear Research, Moscow (Russian Federation); Korolija, M.; Mekterovic, D.; Supek, I. [Rudjer Boskovic Inst., Zagreb (Croatia); Manley, D.M. [Kent State Univ., Kent, OH (United States)] [and others

    2010-03-15

    The reaction {gamma}p{yields}p{pi}{sup 0}{gamma}{sup '} has been measured with the Crystal Ball/TAPS detectors using the energy-tagged photon beam at the electron accelerator facility MAMI-B. Energy and angular differential cross-sections for the emitted photon {gamma}{sup '} and angular differential cross-sections for the {pi}{sup 0} have been determined with high statistics in the energy range of the {delta}{sup +} (1232)-resonance. Cross-sections and the ratio of the cross-section to the nonradiative process {gamma}p{yields}p{pi} {sup 0} are compared to theoretical reaction models, having the anomalous magnetic moment {kappa} {sub {delta}} as free parameter. As the shape of the experimental distributions is not reproduced in detail by the model calculations, currently no extraction of {kappa}{sub {delta}} is feasible. (orig.)

  12. Radiative pi0 photoproduction on protons in the Delta+(1232) region

    CERN Document Server

    Schumann, S; Downie, E J; Aguar-Bartolomé, P; Ahrens, J; Annand, J R M; Arends, H J; Beck, R; Bekrenev, V; Braghieri, A; Branford, D; Briscoe, W J; Brudvik, J W; Cherepnya, S; Codling, R; Drexler, P; Fil'kov, L V; Glazier, D I; Gregor, R; Heid, E; Hornidge, D; Jahn, O; Kashevarov, V L; Kondratiev, R; Korolija, M; Kotulla, M; Krambrich, D; Krusche, B; Lang, M; Lisin, V; Livingston, K; Lugert, S; MacGregor, I J D; Manley, D M; Martinez-Fabregate, M; McGeorge, J C; Mekterovic, D; Metag, V; Nefkens, B M K; Nikolaev, A; Novotny, R; Ostrick, M; Owens, R O; Pedroni, P; Polonski, A; Prakhov, S N; Price, J W; Rosner, G; Rost, M; Rostomyan, T; Sober, D; Starostin, A; Supek, I; Tarbert, C M; Thomas, A; Unverzagt, M; Walcher, Th; Watts, D P; Zehr, F

    2010-01-01

    The reaction gamma p -> p pi0 gamma' has been measured with the Crystal Ball / TAPS detectors using the energy-tagged photon beam at the electron accelerator facility MAMI-B. Energy and angular differential cross sections for the emitted photon gamma' and angular differential cross sections for the pi0 have been determined with high statistics in the energy range of the Delta+(1232) resonance. Cross sections and the ratio of the cross section to the non-radiative process gamma p -> p pi0 are compared to theoretical reaction models, having the anomalous magnetic moment kappa_Delta+ as free parameter. As the shape of the experimental distributions is not reproduced in detail by the model calculations, currently no extraction of kappa_Delta+ is feasible.

  13. Regional review: the hydrology of the Okavango Delta, Botswana-processes, data and modelling

    DEFF Research Database (Denmark)

    Milzow, C.; Kgotlhang, L.; Bauer-Gottwein, Peter

    2009-01-01

    of the Delta has to be understood. This article reviews scientific work done for that purpose, focussing on the hydrological modelling of surface water and groundwater. Research providing input data to hydrological models is also presented. It relies heavily on all types of remote sensing. The history......The wetlands of the Okavango Delta accommodate a multitude of ecosystems with a large diversity in fauna and flora. They not only provide the traditional livelihood of the local communities but are also the basis of a tourism industry that generates substantial revenue for the whole of Botswana...

  14. Endocrine-disrupting chemicals in the Pearl River Delta and coastal environment: sources, transfer, and implications.

    Science.gov (United States)

    Xu, Weihai; Yan, Wen; Huang, Weixia; Miao, Li; Zhong, Lifeng

    2014-12-01

    A study was conducted to investigate the occurrence and behavior of six endocrine-disrupting chemicals (EDCs) in sewage, river water, and seawater from the Pearl River Delta (PRD). The six EDCs under study were 4-nonylphenol (NP), bisphenol A (BPA), 17α-ethynylestradiol (EE2), estrone (E2), 17β-estradiol (E2), and estriol (E3). These EDCs, predominated by BPA, were found in high levels in the influents and the effluents of sewage treatment plants in the area. The relatively high concentrations (0.23-625 ng/L) of the EDCs detected in the receiving river water suggested that the untreated sewage discharge was a major contributor. The EDCs detected in eight outlets of the Pear River and the Pear River Estuary were in the ranges of 1.2-234 and 0.2-178 ng/L, respectively. The estrogen equivalents in the aquatic environments under study ranged from 0.08 to 4.5 ng/L, with E1 and EE2 being the two predominant contributors. As the fluxes of the EDCs from the PRD region to the nearby ocean are over 500 tons each year, the results of this study point to the potential that Pearl River is a significant source of the EDCs to the local environment there.

  15. Regional review: the hydrology of the Okavango Delta, Botswana—processes, data and modelling

    Science.gov (United States)

    Milzow, Christian; Kgotlhang, Lesego; Bauer-Gottwein, Peter; Meier, Philipp; Kinzelbach, Wolfgang

    2009-09-01

    The wetlands of the Okavango Delta accommodate a multitude of ecosystems with a large diversity in fauna and flora. They not only provide the traditional livelihood of the local communities but are also the basis of a tourism industry that generates substantial revenue for the whole of Botswana. For the global community, the wetlands retain a tremendous pool of biodiversity. As the upstream states Angola and Namibia are developing, however, changes in the use of the water of the Okavango River and in the ecological status of the wetlands are to be expected. To predict these impacts, the hydrology of the Delta has to be understood. This article reviews scientific work done for that purpose, focussing on the hydrological modelling of surface water and groundwater. Research providing input data to hydrological models is also presented. It relies heavily on all types of remote sensing. The history of hydrologic models of the Delta is retraced from the early box models to state-of-the-art distributed hydrological models. The knowledge gained from hydrological models and its relevance for the management of the Delta are discussed.

  16. Daily Changes of Spatial Patterns of Meteorological Elements over Pearl River Delta Based on GIS and MM5

    Institute of Scientific and Technical Information of China (English)

    JIANG Xueding; XIA Beicheng; LIN Guangfa; LIN Wenshi

    2009-01-01

    The spatial distribution of meteorological elements is important for understanding the regional meteorology and climate changes. However, previous studies rarely focused on the daily changes of the spatial patterns of meteorological elements due to the limitation of remote sensing (RS) techniques and traditional meteorological methods. In this paper, the regional meteorological elements were simulated by the fifth-generation non-hydrostatic Mesoscale Model (MM5), and the spatial patterns of meteorological elements and their diurnal variations were analyzed in landscape level over the Pearl (Zhujiang) River Delta (PRD), China. The results showed that there were several centers of urban heat islands, cold islands, dry islands, wet islands, high wind over the PRD at noon. The diurnal changes of Moran I of meteorological elements were obvious and they reached the extremum at noon and 2-3 hours after the sunrise. The landscape indices of meteorological elements, such as area-weighted mean Fractal Dimension Index (FRAC_AM), Landscape Shape Index (LSI), Shannon's Diversity Index (SHDI) and Contagion Index (CONTAG), were more variable at about the sunrise, noon and sunset. The occurrence of wave crests and vales of landscape indices was affected by the surface net radiation, turbulence and local circumfluence. The spatial patterns of meteorological elements correlated well with the land surface, thermal exchanges and local circumfluence. A new approach combining GIS, RS and numerical simulatious technologies and the landscape ecology method was presented to analyze spatial patterns of meteorological elements, which may be useful for studying global and regional climate changes.

  17. Industrial sector-based volatile organic compound (VOC) source profiles measured in manufacturing facilities in the Pearl River Delta, China.

    Science.gov (United States)

    Zheng, Junyu; Yu, Yufan; Mo, Ziwei; Zhang, Zhou; Wang, Xinming; Yin, Shasha; Peng, Kang; Yang, Yang; Feng, Xiaoqiong; Cai, Huihua

    2013-07-01

    Industrial sector-based VOC source profiles are reported for the Pearl River Delta (PRD) region, China, based source samples (stack emissions and fugitive emissions) analyzed from sources operating under normal conditions. The industrial sectors considered are printing (letterpress, offset and gravure printing processes), wood furniture coating, shoemaking, paint manufacturing and metal surface coating. More than 250 VOC species were detected following US EPA methods TO-14 and TO-15. The results indicated that benzene and toluene were the major species associated with letterpress printing, while ethyl acetate and isopropyl alcohol were the most abundant compounds of other two printing processes. Acetone and 2-butanone were the major species observed in the shoemaking sector. The source profile patterns were found to be similar for the paint manufacturing, wood furniture coating, and metal surface coating sectors, with aromatics being the most abundant group and oxygenated VOCs (OVOCs) as the second largest contributor in the profiles. While OVOCs were one of the most significant VOC groups detected in these five industrial sectors in the PRD region, they have not been reported in most other source profile studies. Such comparisons with other studies show that there are differences in source profiles for different regions or countries, indicating the importance of developing local source profiles. Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.

  18. MHD simulations of formation and eruption of a magnetic flux rope in an active region with a delta-sunspot

    Science.gov (United States)

    Yokoyama, Takaaki; Oi, Yoshiaki; Toriumi, Shin

    2017-08-01

    Active regions holding a delta-sunspot are known to produce the largest class of solar flares. How, where, and when such large flares occur above a delta-sunspot are still under debate. For studying this, 3D MHD simulations of the emergence of a subsurface flux tube at two locations in a simulation box modeling the convection zone to the corona were conducted. We found that a flux rope is formed as a consequence of magnetic reconnection of two bipolar loops and sunspot rotation caused by the twist of the subsurface flux tube. Moreover, the flux rope stops ascending when the initial background is not magnetized, whereas it rises up to the upper boundary when a reconnection favorably oriented pre-existing field is introduced to the initial background.

  19. Hotspot of glyoxal over the Pearl River delta seen from the OMI satellite instrument: implications for emissions of aromatic hydrocarbons

    Science.gov (United States)

    Miller, Christopher Chan; Jacob, Daniel J.; González Abad, Gonzalo; Chance, Kelly

    2016-04-01

    The Pearl River delta (PRD) is a densely populated hub of industrial activity located in southern China. OMI (Ozone Monitoring Instrument) satellite observations reveal a large hotspot of glyoxal (CHOCHO) over the PRD that is almost twice as large as any other in Asia. Formaldehyde (HCHO) and NO2 observed by OMI are also high in the PRD but no more than in other urban/industrial areas of China. The CHOCHO hotspot over the PRD can be explained by industrial paint and solvent emissions of aromatic volatile organic compounds (VOCs), with toluene being a dominant contributor. By contrast, HCHO in the PRD originates mostly from VOCs emitted by combustion (principally vehicles). By applying a plume transport model to wind-segregated OMI data, we show that the CHOCHO and HCHO enhancements over the PRD observed by OMI are consistent with current VOC emission inventories. Prior work using CHOCHO retrievals from the SCIAMACHY satellite instrument suggested that emission inventories for aromatic VOCs in the PRD were too low by a factor of 10-20; we attribute this result in part to bias in the SCIAMACHY data and in part to underestimated CHOCHO yields from oxidation of aromatics. Our work points to the importance of better understanding CHOCHO yields from the oxidation of aromatics in order to interpret space-based CHOCHO observations in polluted environments.

  20. A regional coupled surface water/groundwater model of the Okavango Delta, Botswana

    Science.gov (United States)

    Bauer, Peter; Gumbricht, Thomas; Kinzelbach, Wolfgang

    2006-04-01

    In the endorheic Okavango River system in southern Africa a balance between human and environmental water demands has to be achieved. The runoff generated in the humid tropical highlands of Angola flows through arid Namibia and Botswana before forming a large inland delta and eventually being consumed by evapotranspiration. With an approximate size of about 30,000 km2, the Okavango Delta is the world's largest site protected under the convention on wetlands of international importance, signed in 1971 in Ramsar, Iran. The extended wetlands of the Okavango Delta, which sustain a rich ecology, spectacular wildlife, and a first-class tourism infrastructure, depend on the combined effect of the highly seasonal runoff in the Okavango River and variable local climate. The annual fluctuations in the inflow are transformed into vast areas of seasonally inundated floodplains. Water abstraction and reservoir building in the upstream countries are expected to reduce and/or redistribute the available flows for the Okavango Delta ecosystem. To study the impacts of upstream and local interventions, a large-scale (1 km2 grid), coupled surface water/groundwater model has been developed. It is composed of a surface water flow component based on the diffusive wave approximation of the Saint-Venant equations, a groundwater component, and a relatively simple vadose zone component for calculating the net water exchange between land and atmosphere. The numerical scheme is based on the groundwater simulation software MODFLOW-96. Since the primary model output is the spatiotemporal distribution of flooded areas and since hydrologic data on the large and inaccessible floodplains and tributaries are sparse and unreliable, the model was not calibrated with point hydrographs but with a time series of flooding patterns derived from satellite imagery (NOAA advanced very high resolution radiometer). Scenarios were designed to study major upstream and local interventions and their expected impacts

  1. Extraction and analysis of impervious surfaces based on a spectral un-mixing method using Pearl River Delta of China Landsat TM/ETM+ imagery from 1998 to 2008.

    Science.gov (United States)

    Deng, Yingbin; Fan, Fenglei; Chen, Renrong

    2012-01-01

    Impervious surface area (ISA) is considered as an indicator of environment change and is regarded as an important input parameter for hydrological cycle simulation, water management and area pollution assessment. The Pearl River Delta (PRD), the 3rd most important economic district of China, is chosen in this paper to extract the ISA information based on Landsat images of 1998, 2003 and 2008 by using a linear spectral un-mixing method and to monitor impervious surface change by analyzing the multi-temporal Landsat-derived fractional impervious surface. Results of this study were as follows: (1) the area of ISA in the PRD increased 79.09% from 1998 to 2003 and 26.88% from 2003 to 2008 separately; (2) the spatial distribution of ISA was described according to the 1998/2003 percentage respectively. Most of middle and high percentage ISA was located in northwestern and southeastern of the whole delta, and middle percentage ISA was mainly located in the city interior, high percentage ISA was mainly located in the suburban around the city accordingly; (3) the expanding direction and trend of high percentage ISA was discussed in order to understand the change of urban in this delta; High percentage ISA moved from inner city to edge of urban area during 1998-2003 and moved to the suburban area that far from the urban area mixed with jumpily and gradually during 2003-2008. According to the discussion of high percentage ISA spatial expanded direction, it could be found out that high percentage ISA moved outward from the centre line of Pearl River of the whole delta while a high ISA percentage in both shores of the Pearl River Estuary moved toward the Pearl River; (4) combining the change of ISA with social conditions, the driving relationship was analyzed in detail. It was evident that ISA percentage change had a deep relationship with the economic development of this region in the past ten years. Contemporaneous major sport events (16th Asia Games of Guangzhou, 26th Summer

  2. Extraction and Analysis of Impervious Surfaces Based on a Spectral Un-Mixing Method Using Pearl River Delta of China Landsat TM/ETM+ Imagery from 1998 to 2008

    Directory of Open Access Journals (Sweden)

    Renrong Chen

    2012-02-01

    Full Text Available Impervious surface area (ISA is considered as an indicator of environment change and is regarded as an important input parameter for hydrological cycle simulation, water management and area pollution assessment. The Pearl River Delta (PRD, the 3rd most important economic district of China, is chosen in this paper to extract the ISA information based on Landsat images of 1998, 2003 and 2008 by using a linear spectral un-mixing method and to monitor impervious surface change by analyzing the multi-temporal Landsat-derived fractional impervious surface. Results of this study were as follows: (1 the area of ISA in the PRD increased 79.09% from 1998 to 2003 and 26.88% from 2003 to 2008 separately; (2 the spatial distribution of ISA was described according to the 1998/2003 percentage respectively. Most of middle and high percentage ISA was located in northwestern and southeastern of the whole delta, and middle percentage ISA was mainly located in the city interior, high percentage ISA was mainly located in the suburban around the city accordingly; (3 the expanding direction and trend of high percentage ISA was discussed in order to understand the change of urban in this delta; High percentage ISA moved from inner city to edge of urban area during 1998–2003 and moved to the suburban area that far from the urban area mixed with jumpily and gradually during 2003–2008. According to the discussion of high percentage ISA spatial expanded direction, it could be found out that high percentage ISA moved outward from the centre line of Pearl River of the whole delta while a high ISA percentage in both shores of the Pearl River Estuary moved toward the Pearl River; (4 combining the change of ISA with social conditions, the driving relationship was analyzed in detail. It was evident that ISA percentage change had a deep relationship with the economic development of this region in the past ten years. Contemporaneous major sport events (16th Asia Games of

  3. Observation and modelling of OH and HO2 concentrations in the Pearl River Delta 2006: a missing OH source in a VOC rich atmosphere

    Directory of Open Access Journals (Sweden)

    M. Shao

    2012-02-01

    Full Text Available Ambient OH and HO2 concentrations were measured by laser induced fluorescence (LIF during the PRIDE-PRD2006 (Program of Regional Integrated Experiments of Air Quality over the Pearl River Delta, 2006 campaign at a rural site downwind of the megacity of Guangzhou in Southern China. The observed OH concentrations reached daily peak values of (15–26 × 106 cm−3 which are among the highest values so far reported for urban and suburban areas. The observed OH shows a consistent high correlation with j(O1D over a broad range of NOx conditions. The correlation cannot be reproduced by model simulations, indicating that OH stabilizing processes are missing in current models. The observed OH exhibited a weak dependence on NOx in contrast to model predictions. While modelled and measured OH agree well at NO mixing ratios above 1 ppb, a continuously increasing underprediction of the observed OH is found towards lower NO concentrations, reaching a factor of 8 at 0.02 ppb NO. A dependence of the modelled-to-measured OH ratio on isoprene cannot be concluded from the PRD data. However, the magnitude of the ratio fits into the isoprene dependent trend that was reported from other campaigns in forested regions. Hofzumahaus et al. (2009 proposed an unknown OH recycling process without NO, in order to explain the high OH levels at PRD in the presence of high VOC reactivity and low NO. Taking a recently discovered interference in the LIF measurement of HO2 into account, the need for an additional HO2 → OH recycling process persists, but the required source strength may be up to 20% larger than previously determined. Recently postulated isoprene mechanisms by Lelieveld et al. (2008 and Peeters and Müller (2010 lead to significant enhancements of OH expected for PRD, but an underprediction of the observed OH by a factor of two remains at low NO (0.1–0.2 ppb. If the photolysis of hydroperoxy aldehydes from isoprene is as efficient as proposed by Peeters and M

  4. Observation and modelling of OH and HO2 concentrations in the Pearl River Delta 2006: a missing OH source in a VOC rich atmosphere

    Directory of Open Access Journals (Sweden)

    M. Shao

    2011-04-01

    Full Text Available Ambient OH and HO2 concentrations were measured by laser induced fluorescence (LIF during the PRIDE-PRD2006 (Program of Regional Integrated Experiments of Air Quality over the Pearl River Delta, 2006 campaign at a rural site downwind of the megacity of Guangzhou in Southern China. The observed OH concentrations reached daily peak values of (15–26 × 106 cm−3 which are among the highest values so far reported for urban and suburban areas. The observed OH shows a consistent high correlation with j(O1D over a broad range of NOx conditions. The correlation cannot be reproduced by model simulations, indicating that OH stabilizing processes are missing in current models. The observed OH exhibited a weak dependence on NOx in contrast to model predictions. While modelled and measured OH agree well at NO mixing ratios above 1 ppb, a continuously increasing underprediction of the observed OH is found towards lower NO concentrations, reaching a factor of 8 at 0.02 ppb NO. A dependence of the modelled-to-measured OH ratio on isoprene cannot be concluded from the PRD data. However, the magnitude of the ratio fits into the isoprene dependent trend that was reported from other campaigns in forested regions. Hofzumahaus et al. (2009 proposed an unknown OH recycling process without NO, in order to explain the high OH levels at PRD in the presence of high VOC reactivity and low NO. Taking a recently discovered interference in the LIF measurement of HO2 into account, the need for an additional HO2 → OH recycling process persists, but the required source strength may be up to 20% larger than previously determined. Recently postulated isoprene mechanisms by Lelieveld et al. (2008 and Peeters and Müller (2010 lead to significant enhancements of OH expected for PRD, but an underprediction of the observed OH by a factor of two remains at low NO (0.1–0.2 ppb. If the photolysis of hydroperoxy aldehydes from isoprene is as efficient as proposed by Peeters and M

  5. PRD3000: A novel Personnel Radiation Detector with Radiation Exposure Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Fallu-Labruyere, A.; Micou, C.; Schulcz, F.; Fellinger, J. [Mirion Technologies - MGPI SA (France)

    2015-07-01

    PRD3000{sup TM} is a novel Personal Radiation Detector (PRD) with personnel radiation dose exposure monitoring. It is intended for First Responders, Law Enforcement, Customs Inspectors protecting critical infrastructures for detecting unexpected radioactive sources, who also need real time Hp(10) dose equivalent information. Traditional PRD devices use scintillator materials instrumented through either a photomultiplier tube or a photodiode photodetector. While the former is bulky and sensitive to magnetic fields, the latter has to compromise radiation sensitivity and energy threshold given its current noise per unit of photo-detection surface. Recently, solid state photodetectors (SiPM), based on arrays of Geiger operated diodes, have emerged as a scalable digital photodetector for photon counting. Their strong breakdown voltage temperature dependence (on the order of tens of milli-volts per K) has however limited their use for portable instruments where strong temperature gradients can be experienced, and limited power is available to temperature stabilize. The PRD3000 is based on the industry standard DMC3000 active dosimeter that complies with IEC 61526 Ed. 3 and ANSI 42.20 for direct reading personal dose equivalent meters and active personnel radiation monitors. An extension module is based on a CsI(Tl) scintillator readout by a temperature compensated SiPM. Preliminary nuclear tests combined with a measured continuous operation in excess of 240 hours from a single AAA battery cell indicate that the PRD3000 complies with the IEC 62401 Ed.2 and ANSI 42.32 without sacrificing battery life time. We present a summary of the device test results, starting with performance stability over a temperature range of - 20 deg. C to 50 deg. C, false alarm rates and dynamic response time. (authors)

  6. Effects of Climate Change on the Production and Profitability of Cassava in the Niger Delta Region of Nigeria

    Directory of Open Access Journals (Sweden)

    J. O. Ajayi

    2015-06-01

    Full Text Available Nigeria is the single largest producer of cassava in the world with the bulk of the cassava coming out from the Niger Delta region. Human, economic and agricultural activities are currently threatened in the region by vagaries in climatic factors. These vagaries affect the production and profitability of cassava. The study was therefore conducted to assess the effects of climate change on the production and profitability of cassava in the Niger Delta region of Nigeria. The study made use of a multi-stage sampling technique to select three hundred and sixty respondents across the three highest cassava-producing states (Awka Ibom, Cross Rivers and Ondo in the region. Data for the study were collected with the aid of well-structured questionnaires assisted with interview schedules. Data collected were analysed using descriptive statistics and regression model. The determinants of cassava profitability were farm size, farmers’ experience in cassava cultivation, farmers’ experience in adopting climate change coping strategies, number of climate change coping strategies adopted, costs of input materials in Naira and labour cost in Naira.

  7. Causes of Wetland Degradation and Ecological Restoration in the Yellow River Delta Region

    Institute of Scientific and Technical Information of China (English)

    Zhang Jian-feng; Sun Qi-xiang

    2005-01-01

    Yellow River delta (YRD) is one of the biggest deltas that there is a large area of wetland in the world. Thanks to soil(sands) sediment carried by the Yellow River, there was averagely the newly formed land 21.3 km2in YRD. During the development of petroleum industry and urban expansion, wetlands were degraded due to population growth, irrational land use, in addition to adverse natural eco-environment such as lower precipitation, higher soil evaporation and soil salinazation. The major ecological measures to restore degraded wetland concerned with ensuring water supply, especially establishing perfect irrigation works; protecting virgin plant communities and assisting them to regenerate by the way of site preparation, improving living surroundings; introducing salt-tolerant plants to increase vegetation species and plant coverage, thereby enhancing the capability of wetland to combat contamination and pollution through plant remediation, uptake, absorption, etc. Finally making a comprehensive land use plan,accordingly removing deleterious facilities.

  8. Discussion on Forestry Sustainable Development in the Yellow River Delta Region

    Institute of Scientific and Technical Information of China (English)

    SUN Qixiang; ZHANG Jianfeng

    2006-01-01

    The Yellow River Delta (YRD) is one of the biggest deltas that have not been developed in the world.During the turn of the centuries, YRD development is listed in the two major projects in the new century by Shandong provincial government.According to the plan, YRD will become an important energy, chemical and agricultural production base in 15-20 years.In view of its location and natural conditions, so far there exist a lot of environmental problems in YRD.Thus the principle of economic development coordinating with environmental protection must be implemented during YRD development.Forestation is one of the vital measures to cope with environment degradation.Therefore, strategies of forestry development and techniques of tree planting in different land use types are discussed in the paper based on site classification with specific problems involved .

  9. Nuclear fragmentation and charge-exchange reactions induced by pions in the $\\Delta$-resonance region

    CERN Document Server

    Feng, Zhao-Qing

    2016-01-01

    Dynamics of the nuclear fragmentations and the charge exchange reactions in pion-nucleus collisions near the $\\Delta$(1232) resonance energies has been investigated within the Lanzhou quantum molecular dynamics (LQMD) transport model. An isospin, momentum and density-dependent pion-nucleon potential is implemented in the model, which influences the pion dynamics, in particular the kinetic energy spectra, but weakly impacts the fragmentation mechanism. The absorption process in pion-nucleon collisions to form the $\\Delta$(1232) resonance dominates the heating mechanism of target nucleus. The excitation energy transferred to the target nucleus increases with the pion kinetic energy and is similar for both $\\pi^{-}$ and $\\pi^{+}$ induced reactions. The magnitude of fragmentation of target nucleus weakly depends on the pion energy. The isospin ratio in the pion double charge exchange is influenced by the isospin ingredient of target nucleus.

  10. Genetic relationships between parishes in the Ebro delta region (Spain) as estimated by migration matrix and surnames.

    Science.gov (United States)

    Esparza, Mireia; García-Moro, Clara; Hernández, Miquel

    2006-12-01

    To determine whether there are preferential relationships among individuals from the different parishes of the Ebro River delta region, we analyzed the population relationships, taking into account both the birthplaces of the spouses and their surname frequencies. We used data from the 9,085 marriages recorded in the Ebro delta area between 1939 and 1995. Using each spouse's birthplace, we calculated the distances between the subject populations by means of the squared Euclidean distance. Also, from the surname frequencies in the marriages we obtained certain kinship measurements. In both analyses the results show a clear differentiation between the parish of Amposta and the rest of the parishes. This difference is mainly due to a greater number of marriages in which delta outsiders participated and can be related to the greater surname diversity and lesser endogamy observed in this population. On the other hand, if only endogamous marriages are taken into account, there is clearly a differentiation between the parishes from both banks of the river, with a strong homogeneity among the northside parishes. We compared the distances obtained from the birthplaces, the kinship parameters obtained from the surnames, and two geographic distance matrixes by means of a Mantel test, and the results show a strong and significant correlation between them when all marriages are considered. If, on the other hand, only endogamous marriages are taken into account, the barrier effect of the river on the interparish relationships can be appreciated.

  11. Pathology of deaths from mob action in the Niger Delta Region of Nigeria. A study of 38 consecutive autopsies.

    Science.gov (United States)

    Seleye-Fubar, D; Etebu, E N; Athanasius, B

    2011-01-01

    Mob action is posing an undue social and public health problems in Niger Delta region of Nigeria; as victims who were said to have committed crime were violently killed without fair trial by law. There is need to research into the pattern, cause and frequency of deaths from mob action. To study the pattern cause and frequency of death from mob action. Niger Delta Region of Nigeria. Aten (1999-2008) consecutive autopsy on victims ofmob action. A thorough autopsy was performed on all the victims following standard method after being severed with the coroner's inquest form by police. Variables considered were the ages and sex, yearly frequency, methods applied in the killing and reasons that motivated the killing. These were obtained from the coroner's inquest forms, police, relations and eye witnesses. A total of thirty eight bodies were examined. Thirty four (89.5%) were males and four (10.5%) females; giving a male to female ratio of 8.5:1. The youngest was 16 years old male while the oldest 72-year-old male. Majority 30 (78.9%) of deaths occurred below the age of 50 years. Youths of the age group 20 29 were most involved and the highest frequency 12 (21.1%) of death was recorded in 2004. Beating 14 (36.8%) was the most common method applied for the killing while political violence 15 (39.5%) was the most common circumstances for the killing. Killing by mob action is a social, legal and public health problem in the Niger Delta region of Nigeria that requires a swift government intervention to reduce the carnage associated with it. Problems of economic inequality, youth unemployment and corruption should be adequately addressed by the Nigerian government.

  12. Distribution and bioconcentration of endocrine disrupting chemicals in surface water and fish bile of the Pearl River Delta, South China.

    Science.gov (United States)

    Yang, Juan; Li, Haiyan; Ran, Yong; Chan, Kingming

    2014-07-01

    The distribution and bioconcentration of endocrine disrupting chemicals (EDCs) in water, algae, and wild carp bile of the Pearl River Delta (PRD), South China were investigated. 4-tert octylphenol (OP), 4-nonylphenol (NP), and bisphenol A (BPA) (unit, ng L(-1)) in water were in the ranges of 1-14, 117-865, and 4-377, those (ng g(-1) dry weight) in algae were in the ranges of 2-13, 53-282, and 16-94, and those (ng g(-1)) in carp bile were in the ranges of 14-39, 950-4648, 70-1020, respectively. Estrone (E1) and 17α-ethinylestradiol (EE2) in water ranged from PRD region. The bioconcentration factors (BCF, L kg(-1)) of OP, NP, BPA, and E1 in algae were in the ranges of 482-7251, 131-740, 2846-12979, and undetectable, respectively, and those in carp bile were in the ranges of 1500-12960, 1648-11137, 3583-14178, and 13208-39623, respectively. The phenolic EDCs can be accumulated by wild carp bile and algae in the investigated aquatic ecosystems, which is also affected by the degree of the eutrophication. This study for the first time reported EDCs in carp bile and algae collected from the PRD, China.

  13. Changing spatial concentration of sectoral employment in China’s Pearl River Delta 1990 - 2005

    NARCIS (Netherlands)

    Cheng, Fangfang; Boerboom, Luc; Geertman, Stan; Hooimeijer, Pieter

    2013-01-01

    Using county-level employment data, we analyse how the spatial concentration of jobs has changed in China's Pearl River Delta (PRD) between 1990 and 2005. Despite unique Chinese policies that exhibit strong influence on the economic landscape, we detect key parallels with the patterns found in class

  14. Changing spatial concentrations of sectorial employment in China's Pearl River Delta

    NARCIS (Netherlands)

    Cheng, F.; Boerboom, L.; Geertman, S.C.M.; Hooimeijer, P.

    2012-01-01

    Using county-level employment data, we analyse how the spatial concentration of jobs has changed in China’s Pearl River Delta (PRD) between 1990 and 2005. Despite unique Chinese policies that exhibit strong influence on the economic landscape, we detect key parallels with the patterns found in class

  15. Changing spatial concentrations of sectorial employment in China's Pearl River Delta

    NARCIS (Netherlands)

    Cheng, F.; Boerboom, L.; Geertman, S.C.M.; Hooimeijer, P.

    2012-01-01

    Using county-level employment data, we analyse how the spatial concentration of jobs has changed in China’s Pearl River Delta (PRD) between 1990 and 2005. Despite unique Chinese policies that exhibit strong influence on the economic landscape, we detect key parallels with the patterns found in

  16. Energy dependence of hard bremsstrahlung production in proton-proton collisions in the Delta(1232) region

    CERN Document Server

    Tsirkov, D; Azaryan, T; Chiladze, D; Dymov, S; Dzyuba, A; Hartmann, M; Kacharava, A; Khoukaz, A; Kulikov, A; Kurbatov, V; Macharashvili, G; Merzliakov, S; Mielke, M; Mikirtychiants, S; Nekipelov, M; Rathmann, F; Serdyuk, V; Stroeher, H; Uzikov, Yu; Valdau, Yu; Wilkin, C

    2010-01-01

    Hard bremsstrahlung production in proton-proton collisions has been studied with the ANKE spectrometer at COSY-Juelich in the energy range of 353-800 MeV by detecting the final proton pair {pp}_s from the pp -> {pp}_s reaction with very low excitation energy. Differential cross sections were measured at small diproton c.m. angles from 0 to 20 degrees and the average over this angular interval reveals a broad peak at a beam energy around 650 MeV with a FWHM of about 220 MeV, suggesting the influence of Delta(1232)N intermediate states. Comparison with deuteron photodisintegration shows that the cross section for diproton production is up to two orders of magnitude smaller, due largely to differences in the selection rules.

  17. Technical and Economic Efficiency of Palm Oil Marketing in the Niger Delta Region of Southern Nigeria

    Directory of Open Access Journals (Sweden)

    Nkasiobi Silas Oguzor

    2013-09-01

    Full Text Available This study examined the structural performance and productive efficiency of palm oil marketing in some selected States in Southern Nigeria. Eighty districts were selected in the Niger Delta Area and data were collected from 1000 palm oil sellers randomly selected in these towns. The tools of analysis were marketing margin, Lorenz curve and Gini coefficient to measure the structural performance while the productive efficiency was measured with the use of the production function analysis using the OLS multiple regression analysis to estimate the parameters of the production function equations. All these phenomena portend a high poor structural performance in the system. The productive efficiency measurement showed that palm oil marketing was in stage one of the production surface in the area and this implies inefficient allocation and utilization of resources. Therefore palm oil marketing in the study is though profitable was grossly inefficient from the view point of market structure and productive efficiency analysis.

  18. Eco Bio Cultural Protocols for Preservation of Endangered Agrobiodiversity Areas from the Adjacent Regions of Danube and Danube Delta

    Directory of Open Access Journals (Sweden)

    Iudith Ipate

    2014-08-01

    Full Text Available Danube Strategy involves creating synergies between different sectors (tourism, environmental protection, agriculture and forestry, promoting solutions and contributing to the prosperity of social, economic and cultural sustainable development. It requires multiinterdisciplinary problem solving biodiversity conservation and environmental protection. Agrobiodiversity conservation and means must be assessed according to international risk categories, taking into account the culture, traditions and local lifestyle. Fundamental aspects of the protocols will be to assess species and breeds endangered and their influence on specific ecosystems of the Danube and Danube Delta to promote local tradition and cultural heritage. Our studies will have to reveal new interdependencies between socio- economic phenomena that occur in the context of regional sustainable development and identify viable solutions to ensure the conservation of agrobiodiversity as part of the natural and cultural heritage of the Danube Delta . Need of cooperation between Danube countries and between local authorities and research entities to conserve natural and cultural heritage that can be achieved based on eco-bio-diplomacy. Need of cooperation between Danube countries and between local authorities and research entities to conserve natural and cultural heritage that can be achieved based on eco-bio-diplomacy.

  19. MULTI-WAVELENGTH STUDY OF A DELTA-SPOT. I. A REGION OF VERY STRONG, HORIZONTAL MAGNETIC FIELD

    Energy Technology Data Exchange (ETDEWEB)

    Jaeggli, S. A., E-mail: sarah.jaeggli@nasa.gov [NASA Goddard Space Flight Center, Solar Physics Laboratory, Code 671, Greenbelt, MD 20771 (United States)

    2016-02-10

    Active region NOAA 11035 appeared in 2009 December, early in the new solar activity cycle. This region achieved a delta sunspot (δ spot) configuration when parasitic flux emerged near the rotationally leading magnetic polarity and traveled through the penumbra of the largest sunspot in the group. Both visible and infrared imaging spectropolarimetry of the magnetically sensitive Fe i line pairs at 6302 and 15650 Å show large Zeeman splitting in the penumbra between the parasitic umbra and the main sunspot umbra. The polarized Stokes spectra in the strongest field region display anomalous profiles, and strong blueshifts are seen in an adjacent region. Analysis of the profiles is carried out using a Milne–Eddington inversion code capable of fitting either a single magnetic component with stray light or two independent magnetic components to verify the field strength. The inversion results show that the anomalous profiles cannot be produced by the combination of two profiles with moderate magnetic fields. The largest field strengths are 3500–3800 G in close proximity to blueshifts as strong as 3.8 km s{sup −1}. The strong, nearly horizontal magnetic field seen near the polarity inversion line in this region is difficult to understand in the context of a standard model of sunspot magnetohydrostatic equilibrium.

  20. [Characteristics Analysis of Sulfur Dioxide in Pearl River Delta from 2006 to 2010].

    Science.gov (United States)

    Li, Fei; Tan, Hao-bo; Deng, Xue-jiao; Deng, Tao; Xu, Wan-yun; Ran, Liang; Zhao, Chun-sheng

    2015-05-01

    Based on the in-situ SO2 observation dataset from 2006 to 2010 in Pearl River Delta(PRD) , the temporal characteristics of SO2 are analyzed. The results show that the annual average volume fraction of surface SO2 in 2010 declines to a level below average values in recent years, with reducing the frequency of high concentration episodes occurring. The seasonal, monthly and diurnal characteristics of surface SO2 are influenced by particular weather conditions in the PRD. The Probability Distribution Function(PDF) of surface SO2 volume fraction are complicated. The PDF is different every month maybe caused by the variation of the seasonal factors.

  1. Progress in understanding the formation of fine particulate matter and ground-level ozone in Pearl River Delta region, China

    Science.gov (United States)

    Wang, Xuemei; Wang, Tao; Zheng, Junyu; Shao, Min; Wang, Xinming

    2015-12-01

    In the past three decades, the Pearl River Delta of China has been suffered from severe air pollution due to the rapid increase in energy consumption associated with industrialization and urbanization of the region. The number of hazy days, increased from below 20 days in a year before 1970, to more than 150 days a year during 1980 and 2000. The ground-level ozone levels have also on the rise, with hourly concentration of 160 ppbv being observed in Guangzhou and 201 ppbv in nearby Hong Kong (Zhang et al., 2008). The ozone pollution has been difficult to reduce even in air quality improvement program for the Guangzhou Asian Games (Liu et al., 2013).

  2. Numerical Study on Emergence of Kinked Flux Tube for Understanding of Possible Origin of Delta-spot Regions

    CERN Document Server

    Takasao, Shinsuke; Cheung, Mark C M; Shibata, Kazunari

    2015-01-01

    We carried out a magnetohydrodynamics simulation where a subsurface twisted kink-unstable flux tube emerges from the solar interior to the corona. Unlike the previous expectations based on the bodily emergence of a knotted tube, we found that the kinked tube can spontaneously form a complex quadrupole structure at the photosphere. Due to the development of the kink instability before the emergence, the magnetic twist at the kinked apex of the tube is greatly reduced, although the other parts of the tube is still strongly twisted. This leads to the formation of a complex quadrupole structure: a pair of the coherent, strongly twisted spots and a narrow complex bipolar pair between it. The quadrupole is formed by the submergence of a portion of emerged magnetic fields. This result is relevant for understanding of the origin of the complex multipolar $\\delta$-spot regions that have a strong magnetic shear and emerge with polarity orientations not following Hale-Nicholson and Joy Laws.

  3. City-specific vehicle emission control strategies to achieve stringent emission reduction targets in China's Yangtze River Delta region.

    Science.gov (United States)

    Zhang, Shaojun; Wu, Ye; Zhao, Bin; Wu, Xiaomeng; Shu, Jiawei; Hao, Jiming

    2017-01-01

    The Yangtze River Delta (YRD) region is one of the most prosperous and densely populated regions in China and is facing tremendous pressure to mitigate vehicle emissions and improve air quality. Our assessment has revealed that mitigating vehicle emissions of NOx would be more difficult than reducing the emissions of other major vehicular pollutants (e.g., CO, HC and PM2.5) in the YRD region. Even in Shanghai, where the emission control implemented are more stringent than in Jiangsu and Zhejiang, we observed little to no reduction in NOx emissions from 2000 to 2010. Emission-reduction targets for HC, NOx and PM2.5 are determined using a response surface modeling tool for better air quality. We design city-specific emission control strategies for three vehicle-populated cities in the YRD region: Shanghai and Nanjing and Wuxi in Jiangsu. Our results indicate that even if stringent emission control consisting of the Euro 6/VI standards, the limitation of vehicle population and usage, and the scrappage of older vehicles is applied, Nanjing and Wuxi will not be able to meet the NOx emissions target by 2020. Therefore, additional control measures are proposed for Nanjing and Wuxi to further mitigate NOx emissions from heavy-duty diesel vehicles.

  4. Regional ozone pollution and key controlling factors of photochemical ozone production in Pearl River Delta during summer time

    Institute of Scientific and Technical Information of China (English)

    CHANG; ChihChung; CHOU; C.K.Charles; Andreas; Wahner

    2010-01-01

    An intensive field campaign including measurements from the environmental monitoring network and from two super sites took place in the Pearl River Delta region in summer 2006.Using routinely measured O3 and NOx concentrations,the spatial and temporal variation of O3 and of the total oxidant concentrations was characterized.According to the spatial variability of NO2/NO,the two super sites were found to be representative of polluted urban and downwind suburban conditions.In addition,both sites were located in high O3 regions.In-depth diagnostic of photochemical ozone production processes and their key controlling factors are achieved with an observation-based model(OBM) to gain regional perspectives.Budget analysis and sensitivity model runs show that aldehyde and HONO chemistry had significant impacts on local photochemical ozone production rates.The analysis of calculated Relative Incremental Reactivities shows that photochemical ozone production rates are mainly sensitive to anthropogenic hydrocarbons(HCs) in the polluted urban areas.In the suburban areas,sensitivity to nitrogen oxide(NO) concentrations dominated.Key anthropogenic HCs in both areas are alkenes and aromatics.Significant differences of ozone production efficiencies are identified between the urban and suburban regions,consistent with the OBM diagnosed results.

  5. The impacts of urbanization on air quality over the Pearl River Delta in winter: roles of urban land use and emission distribution

    Science.gov (United States)

    Chen, Bin; Yang, Shuai; Xu, Xiang-De; Zhang, Wei

    2014-07-01

    In this study, ideal but realistic numerical experiments are performed to explore the relative effects of changes in land use and emission distribution on air quality in the Pearl River Delta (PRD) region in winter. The experiments are accomplished using the Lagrangian particle transport and dispersion model FLEXPART coupled with the Weather Research and Forecasting model under different scenarios. Experiment results show that the maximum changes in daily mean air pollution concentration (as represented by SO2 concentration) caused by land use change alone reaches up to 2 × 10-6 g m-3, whereas changes in concentrations due to the anthropogenic emission distribution are characterized by a maximum value of 6 × 10-6 g m-3. Such results reflect that, although the impacts of land use change on air quality are non-negligible, the emission distribution exerts a more significant influence on air quality than land use change. This provides clear implications for policy makers to control urban air pollution over the PRD region, especially for the urban planning in spatial arrangements for reasonable emissions.

  6. The Indus Irrigation System, Natural Resources, and Community Occupational Quality in the Delta Region of Pakistan

    Science.gov (United States)

    Memon, Junaid Alam; Thapa, Gopal Bahadur

    2011-02-01

    This study examines the impact of an elaborated irrigation system on the natural resources and society in the deltaic part of the Indus River in Pakistan. Time series information was collected to analyze the ecological and natural resource dynamics, and their impacts on the structure and quality of the occupations of the people in the Indus delta during pre- and post-irrigation system development periods. The information was collected through literature review, reconnaissance, structured questionnaire survey, focus group discussions, and interviews. The findings revealed that the expansion of the irrigation system and the resulting reduction in the downstream flow had their differential impacts on the various segments of downstream ecology and society. Some of the resources, for example the agricultural mudflats have been adversely affected due to the accelerated seawater intrusion that severely impinged on the paddy farms. On the other natural resources like mangroves, the impacts had been both negative and positive. On one hand, the diversity of the mangroves species had deteriorated while on other hand, the mangroves have benefited from such development because of the alleviated pressure of camel grazing as a result of the occupational change on the part of the camel herders. Furthermore, changes in the hydrological regimes had forced the paddy farmers and camel herders to switch to fishing as an alternative source of employment and income. Considering that currently about 87% people are already engaged primarily in marine fishery, this scenario is threatening the sustainability of the fishery resources as well as the livelihoods of all, the traditional and converted fishermen. The findings of the study are therefore meant to advocate the different treatments which should be accorded to the various segments of the downstream ecology and society during the planning of any remedial irrigation projects in order to mitigate the adverse impacts of the previous

  7. Transfer of cadmium from soil to vegetable in the Pearl River Delta area, South China.

    Science.gov (United States)

    Zhang, Huihua; Chen, Junjian; Zhu, Li; Yang, Guoyi; Li, Dingqiang

    2014-01-01

    The purpose of this study was to investigate the regional Cadmium (Cd) concentration levels in soils and in leaf vegetables across the Pearl River Delta (PRD) area; and reveal the transfer characteristics of Cadmium (Cd) from soils to leaf vegetable species on a regional scale. 170 paired vegetables and corresponding surface soil samples in the study area were collected for calculating the transfer factors of Cadmium (Cd) from soils to vegetables. This investigation revealed that in the study area Cd concentration in soils was lower (mean value 0.158 mg kg(-1)) compared with other countries or regions. The Cd-contaminated areas are mainly located in west areas of the Pearl River Delta. Cd concentrations in all vegetables were lower than the national standard of Safe vegetables (0.2 mg kg(-1)). 88% of vegetable samples met the standard of No-Polluted vegetables (0.05 mg kg(-1)). The Cd concentration in vegetables was mainly influenced by the interactions of total Cd concentration in soils, soil pH and vegetable species. The fit lines of soil-to-plant transfer factors and total Cd concentration in soils for various vegetable species were best described by the exponential equation (y = ax(b)), and these fit lines can be divided into two parts, including the sharply decrease part with a large error range, and the slowly decrease part with a low error range, according to the gradual increasing of total Cd concentrations in soils.

  8. Transfer of cadmium from soil to vegetable in the Pearl River Delta area, South China.

    Directory of Open Access Journals (Sweden)

    Huihua Zhang

    Full Text Available The purpose of this study was to investigate the regional Cadmium (Cd concentration levels in soils and in leaf vegetables across the Pearl River Delta (PRD area; and reveal the transfer characteristics of Cadmium (Cd from soils to leaf vegetable species on a regional scale. 170 paired vegetables and corresponding surface soil samples in the study area were collected for calculating the transfer factors of Cadmium (Cd from soils to vegetables. This investigation revealed that in the study area Cd concentration in soils was lower (mean value 0.158 mg kg(-1 compared with other countries or regions. The Cd-contaminated areas are mainly located in west areas of the Pearl River Delta. Cd concentrations in all vegetables were lower than the national standard of Safe vegetables (0.2 mg kg(-1. 88% of vegetable samples met the standard of No-Polluted vegetables (0.05 mg kg(-1. The Cd concentration in vegetables was mainly influenced by the interactions of total Cd concentration in soils, soil pH and vegetable species. The fit lines of soil-to-plant transfer factors and total Cd concentration in soils for various vegetable species were best described by the exponential equation (y = ax(b, and these fit lines can be divided into two parts, including the sharply decrease part with a large error range, and the slowly decrease part with a low error range, according to the gradual increasing of total Cd concentrations in soils.

  9. Accumulation, transfer, and environmental risk of soil mercury in a rapidly industrializing region of the Yangtze River Delta, China

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Biao; Yan, Lianxiang; Sun, Weixia; Zhao, Yongcun; Shi, Xuezheng [Chinese Academy of Sciences, Nanjing (China). State Key Lab. of Soil and Sustainable Agriculture; Wang, Mei [Chinese Academy of Sciences, Nanjing (China). State Key Lab. of Soil and Sustainable Agriculture; Graduate Univ. of the Chinese Academy of Sciences, Beijing (China); Weindorf, David C. [Louisiana State Univ., Baton Rouge, LA (United States). AgCenter

    2011-06-15

    Purpose: Mercury (Hg) accumulation and transfer in soil ecosystems has been altered on local, regional, and even global scales, and their environmental risk has increasingly been a concern to the public and the scientific community. Materials and methods: A county level region in Zhangjiagang County, the Yangtze River Delta (YRD) region of China and a factory with Hg-contaminated wastewater discharging within the region were selected to study the accumulation, bioavailability, and transfer of Hg from different sources in soils and crops under rapid industrialization, urbanization, and intensive agricultural activities. Regional soil samples close to and away from factories and local soil and crop samples around a typical factory were collected in the YRD region of China. Soil and crop Hg and basic soil properties were examined. Results and discussion: Significant soil Hg accumulation was found in soils away from factories regardless of Cambosols (Entisols) and Anthrosols (Inceptisols), while the mobile HCl-extractable Hg (HCl-Hg) were greater in soils closer to factories due to a decrease and increase in soil pH and organic matter. A high level of soil total Hg (T-Hg) was found around the factory, and soil and crop Hg accumulation in the vicinity of the factory was localized with an exponential decrease as distance away from the wastewater discharge outlet increased. Although Hg accumulated in these soils, the T-Hg levels at only a few sampling sites in acidic Anthrosols area were found to exceed the second most stringent critical value of Chinese Environmental Quality Standards for Soils. Conclusions: Considering the cessation of Hg-containing agrochemicals and limitation of effects of industrial activities on Hg accumulation, more attention should be paid to the changes in soil properties and crop rotations than controlling the pathways of Hg entering soils because the current environmental risk is mobilization of accumulated soil Hg. (orig.)

  10. WIRELESS SENSOR AND ACTUATOR NETWORKS AS A PROTECTIVE MEANS FOR PIPELINE VANDALISM IN THE NIGER DELTA REGION OF NIGERIA

    Directory of Open Access Journals (Sweden)

    Nwala Kenneth Tochukwu

    2015-10-01

    Full Text Available With the discovery of crude oil in Niger Delta, it was expected that it will usher in the much needed sustainable development in the region, thus, this did was defeated due to high rate of pipeline vandalism in the region, Whereas this did not happen. Activities of the multinational oil companies (MNOC‟s operating in the region continued to pollute and degrade the environment so much that it disarticulated the local economy of the people. The unmet expectations of the people, coupled with the environmental degradation created frustration that consequently led the people to vandalize oil pipelines.Sensor networks offer a powerful combination in communication, distributed sensing and computing. They are appropriate for countless applications and, at the same time, offer large challenges due to their distinctiveness, primarily the rigid energy constraints to which sensing nodes are typically subjected. The noticeable traits of sensor networks have a direct impact on the hardware design of the nodes at least four levels: communication hardware, power source, sensors and processor. Wireless Sensor Networks are self-configured to monitor physical or environmental conditions, such as sound, vibration, temperature, pressure, pollutants or motion and tocooperatively pass their data through the network to a main location or sink where the data can be observed and analysed.

  11. WIRELESS SENSOR AND ACTUATOR NETWORKS AS A PROTECTIVE MEANS FOR PIPELINE VANDALISM IN THE NIGER DELTA REGION OF NIGERIA

    Directory of Open Access Journals (Sweden)

    Nwala Kenneth Tochukwu

    2014-11-01

    Full Text Available With the discovery of crude oil in Niger Delta, it was expected that it will usher in the much needed sustainable development in the region, thus, this did was defeated due to high rate of pipeline vandalism in the region, Whereas this did not happen. Activities of the multinational oil companies (MNOC‟s operating in the region continued to pollute and degrade the environment so much that it disarticulated the local economy of the people. The unmet expectations of the people, coupled with the environmental degradation created frustration that consequently led the people to vandalize oil pipelines.Sensor networks offer a powerful combination in communication, distributed sensing and computing. They are appropriate for countless applications and, at the same time, offer large challenges due to their distinctiveness, primarily the rigid energy constraints to which sensing nodes are typically subjected. The noticeable traits of sensor networks have a direct impact on the hardware design of the nodes at least four levels: communication hardware, power source, sensors and processor. Wireless Sensor Networks are self-configured to monitor physical or environmental conditions, such as sound, vibration, temperature, pressure, pollutants or motion and tocooperatively pass their data through the network to a main location or sink where the data can be observed and analysed.

  12. Aerosol size distribution characteristics of organosulfates in the Pearl River Delta region, China

    Science.gov (United States)

    Kuang, Bin Yu; Lin, Peng; Hu, Min; Yu, Jian Zhen

    2016-04-01

    Organosulfates (OSs) have been detected in various atmospheric environments, but their particle size distribution characteristics are unknown. In this work, we examined their size distributions in ambient aerosols to gain insights into the formation processes. Size-segregated aerosol samples in the range of 0.056-18 μm were collected using a ten-stage impactor at a receptor site in Hong Kong in both summer and winter and in Nansha in the Pearl River Delta in winter. The humic-like substances fraction in the size-segregated samples was isolated and analyzed using electrospray ionization coupled with an Orbitrap Ultra High Resolution Mass Spectrometer. Through accurate mass measurements, ∼190 CHOS and ∼90 CHONS formulas were tentatively identified to be OS compounds. Among them, OS compounds derived from isoprene, α-/β-pinene, and limonene and alkyl OSs having low double bond equivalents (DBE = 0,1) and 0-2 extra O beyond those in -OSO3 were found with high intensity. The biogenic volatile organic compounds-derived OS formulas share a common characteristic with sulfate in that the droplet mode dominated, peaking in either 0.56-1.0 or 1.0-1.8 μm size bin, reflecting sulfate as their common precursor. Most of these OSs have a minor coarse mode, accounting for 0-45%. The presence of OSs on the coarse particles is hypothesized to be a result of OSs on small particle (<0.32 μm) coagulating with coarse particles, as the abundance ratios of OS to non-sea-salt sulfate present on the coarse particles were similar to those on particles <0.32 μm. Among a few pairs of CHONS and CHOS that could be linked up through hydrolysis of a nitrooxy group in the CHONS form (e.g., m/z 294: C10H16O7NS- vs. m/z 249 C10H17O5S- from α/β-pinene, differing by (+H2O-HNO3)), the CHONS compounds had an enhanced coarse mode presence. This could be interpreted as a result of slower hydrolysis of the CHONS compounds on the alkali coarse particles. The low DBE alkyl OS compounds have a

  13. Spatial variations of river water quality in Pearl River Delta, China

    Institute of Scientific and Technical Information of China (English)

    Xiaoyun FAN; Baoshan CUI; Zhiming ZHANG

    2012-01-01

    In Pearl River Delta (PRD),river water quality has deteriorated gradually due to population increase and ongoing industrialization and urbanization.In this study,multivariate statistic methods were used to assess water quality spatial pattern and to identify characteristics of water quality variation in the PRD.Water quality monitoring of the PRD during the year 2005 and 2008 was conducted at 25 different stations.Seventeen water quality parameters were analyzed for further studying.Results of one-way analysis of variance (ANOVA) indicated that all the parameters except air temperature,water temperature and zinc showed significant difference among monitoring stations in both dry and wet season.Monitoring stations in the PRD were separately classified into three statistically significant clusters at (Dlink/Dmax) <2 in dry and wet season,respectively.The three clusters indicated the similarity and dissimilarity of river water quality among 25 monitoring stations,corresponding to heavy pollution,moderate pollution and slight pollution.Thus,the results of this study are useful to evaluate water quality and manage water resources in the PRD.

  14. El PRD: Proceso de aprendizaje, trayectoria electoral y organización

    OpenAIRE

    Esperanza Palma

    2000-01-01

    A pesar de haber elementos contradictorios en el escenario perredista podría plantearse que en términos generales, la intransigencia democrática ha sido prácticamente abandonada durante el gobierno de Zedillo, como resultado de una combinación de factores externos e internos a la organización: la experiencia de las elecciones de 1994, la reforma electoral de 1996, la posición del presidente Zedillo frente al PRD, quien desde el inicio de su gobierno manifestó su intención de integrar a este p...

  15. HIV voluntary testing and perceived risk among female sex workers in the Mekong Delta region of Vietnam

    Directory of Open Access Journals (Sweden)

    Bach Xuan Tran

    2013-07-01

    Full Text Available Introduction: HIV voluntary counseling and testing (VCT comprise an effective preventive measure and an entry point to care and support services. We sought to assess VCT uptake and HIV-related knowledge and perceived risk among female sex workers (FSWs in five provinces of the Mekong Delta region. Methods: A cross-sectional survey was carried out in 1998 FSWs, including both street-based sex workers (SSWs and entertainment-based sex workers (ESWs. Results: High proportions of FSWs were aware that using condoms (94.6%, and clean needles (34.1% are preventive measures that reduce the risk of HIV transmission. Some FSWs reported avoiding public toilet use (8.6%, physical contacts (16.1%, or sharing meals (10.9% with people living with HIV/AIDS, and preventing mosquito bites (20.8%. Twenty-nine percent (29.0% of FSWs perceived themselves as being at risk of HIV infection. Only 32.7% had ever tested for HIV, of whom 54% were voluntary for testing. FSWs who ever injected drugs (OR = 0.03, p=0.05, had drug-injecting clients (OR = 0.07, p<0.01, and had inconsistent condom use with husbands or lovers (OR = 0.10, p=0.01 were less likely to have a voluntary test. Inconsistent condom use with clients (OR = 13.86, p<0.01, and receiving HIV information from radio (OR = 13.28, p<0.05 and communication campaigns (OR = 6.69, p<0.05, increased the likelihood of VCT uptake. Conclusion: Inadequate knowledge and some misconceptions about HIV transmission routes and preventive measures, low perceived risk of HIV infection, and low VCT uptake were observed among FSWs in the Mekong Delta region. Interventions to improve their knowledge and self-efficacy, reduce risky behaviors, and encourage VCT uptake and early access to health care services are necessary to prevent HIV transmission in this region.

  16. Factors Influencing the Improved Academic Success in Literacy at the Knowledge Is Power Program School in the Delta Region According to Administrator, Teacher, and Student Perceptions: Case Study

    Science.gov (United States)

    Brown, Kimberly Jonetta

    2012-01-01

    The purpose of this study was to explore the factors that have influenced the literacy success of the Knowledge is Power Program (KIPP) students in the low-income, poverty stricken Delta Region of a mid-south state. The study examined the progress made since the implementation of the KIPP Program and the influence the program has made upon student…

  17. Factors Influencing the Improved Academic Success in Literacy at the Knowledge Is Power Program (KIPP) Schools in the Delta Region According to Adult Perceptions

    Science.gov (United States)

    Brown, Kimberly J.; Holt, Carleton R.

    2014-01-01

    This qualitative case study explored factors that have influenced literacy success of Knowledge is Power Program (KIPP) students in the low-income, poverty stricken Delta Region of Arkansas. The study examined progress made since implementation of the KIPP Program and the influence the program had made upon student achievement in literacy at the…

  18. Mercury speciation and emission from municipal solid waste incinerators in the Pearl River Delta, South China.

    Science.gov (United States)

    Chen, Laiguo; Liu, Ming; Fan, Ruifang; Ma, Shexia; Xu, Zhencheng; Ren, Mingzhong; He, Qiusheng

    2013-03-01

    The potential for Hg release during municipal solid waste incineration (MSWI) is attracting increased attention due to high volume of municipal waste being treated by incineration in China. Emission amounts have been estimated using emission factors developed for other countries. To fine tune our emission estimate total mercury (THg) and mercury speciation were measured using isokinetic sampling in eight plants, of which six used grate furnace combustor (GFC) and two circulation fluidized bed combustors (CFBCs). Results showed that average THg concentration (19.5 ± 13.6 μg/Nm) in flue gas at the facilities that used CFBC was significantly lower than that at those using GFC (51.4 ± 28.3 μg/Nm, p=0.002). Gaseous oxidized mercury (GOM), gaseous elemental mercury (GEM, Hg), and particulate mercury (Hg) represented 95.5 ± 3.8%, 4.1 ± 3.9% and 0.4 ± 0.3% in GFC, and 63.8 ± 8.6%, 33.6 ± 10.5% and 2.6 ± 1.9% in CFBC, respectively. The measured average THg emission factor for the 8 MSWI plants was 208 ± 130 mg/t in the Pearl River Delta (PRD) region, with 217 ± 158 mg/t and 188 ± 17.7 mg/t were from GFC and CFBC, respectively. Using the average emission factor the estimated total mercury emissions from MSWI were 4.67 ± 2.91 t in China, and 770 ± 65.5 kg in the PRD region in 2010. Of these, 4240 ± 210 kg, 408 ± 231 kg and 14.8 ± 14.1 kg, and 688 ± 37 kg, 78.9 ± 40.6 kg and 3.2 ± 3.0 kg were GOM, Hg, and Hg, respectively. Mercury emissions will continue to increase as the amounts of MSW being incinerated increases.

  19. Reach-scale variation surface water quality in a reticular canal system in the lower Yangtze River Delta region, China.

    Science.gov (United States)

    Griffiths, James Andrew; Chan, Faith Ka Shun; Zhu, Fangfang; Wang, Vickie; Higgitt, David Laurence

    2017-07-01

    The aim of this research was to assess the spatial and temporal distribution of surface water pollution within a reticular canal system typical of those found in the lower Yangtze River Delta (YRD). For this purpose, surface water quality data was collected from a drainage canal that bisected the southeast district of Ningbo Municipality (Zhejiang) from 2013 to 2015. The sampling transect was designed to represent the change in land-use from the agriculture dominated rural hinterland, to the predominantly urban city-centre. To calculate the representative land-use fraction of each sampling location, the contributing area was defined using an uni-directional 1 km vector line-buffer around the 'upstream' section of canal. The spatial and temporal variation of EC, DO, NH3 and turbidity indicated a measureable difference between the urban and rural sections of the channel. Water quality indicators were most sensitive to urban and parkland land-use types. The study yielded an increased spatial resolution to knowledge of water-quality variability in the urban environment compared to previous studies within the YRD region. The results were used to make recommendations for the development of an effective long-term strategy for the improvement in surface water quality in this region. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Clinico-epidemiological study on canine toxicosis in Effurun/Warri Municipality region of Delta State, Nigeria

    Directory of Open Access Journals (Sweden)

    Kundu F. Shima

    2015-09-01

    Full Text Available The purpose of this study was to provide fundamental information on both the common toxicants and poisoning episodes in dogs within Effurun/Warri municipality region of Delta State of Nigeria from 2011 to 2014. The collected data were grouped according to age, sex, breed, year of occurrence, and toxicant type. The study revealed that a total of 76 dogs comprising 12 breeds were poisoned by several toxicants such as pesticides (69%; n=52/76, household products (12%; n=9/76, food and ndash;poisons (9%; n=7/76, and snakebite envenomation (3%; n=2/76. Mixed breeds (29%; n=22/76, Alsatian (25%; n=19/76, Rottweiler (16%; n=12/76 and indigenous breed (7%; n=5/76 ranked the topmost breeds accounted for most poison emergencies with human and ndash;related factors incriminated. This study provides useful information on episodes of poisoning in dogs in the studied region. The knowledge of agents involved can help veterinarians for accurate diagnosis, and pet owners to cautiously protect their pets from potentially poisonous substances. [J Adv Vet Anim Res 2015; 2(3.000: 357-361

  1. [Prediction and simulation of urban area expansion in Pearl River Delta Region under the RCPs climate scenarios].

    Science.gov (United States)

    Jiang, Oun-ou; Deng, Xiang-zheng; Ke, Xin-li; Zhao, Chun-hong; Zhang, Wei

    2014-12-01

    The sizes and number of cities in China are increasing rapidly and complicated changes of urban land use system have occurred as the social economy develops rapidly. This study took the urban agglomeration of Pearl River Delta Region as the study area to explore the driving mechanism of dynamic changes of urban area in the urbanization process under the joint influence of natural environment and social economic conditions. Then the CA (cellular automata) model was used to predict and simulate the urban area changes until 2030 under the designed scenarios of planning and RCPs (representative concentration pathways). The results indicated that urbanization was mainly driven by the non-agricultural population growth and social-economic development, and the transportation had played a fundamental role in the whole process, while the areas with high elevation or steep slope restricted the urbanization. Besides, the urban area would keep an expanding trend regardless of the scenarios, however, the expanding speed would slow down with different inflection points under different scenarios. The urban expansion speed increased in the sequence of the planning scenario, MESSAGE scenario and AIM scenario, and that under the MESSAGE climate scenario was more consistent with the current urban development trend. In addition, the urban expansion would mainly concentrate in regions with the relatively high urbanization level, e.g., Guangzhou, Dongguan, Foshan, Shenzhen, Zhanjiang and Chaoshan.

  2. Characterizing and sourcing ambient PM2.5 over key emission regions in China II: Organic molecular markers and CMB modeling

    Science.gov (United States)

    Zhou, Jiabin; Xiong, Ying; Xing, Zhenyu; Deng, Junjun; Du, Ke

    2017-08-01

    From November 2012 to July 2013, a sampling campaign was completed for comprehensive characterization of PM2.5 over four key emission regions in China: Beijing-Tianjin-Hebei (BTH), Yangzi River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB). A multi-method approach, adopting different analytical and receptor modeling methods, was employed to determine the relative abundances of region-specific air pollution constituents and contributions of emission sources. This paper is focused on organic molecular marker based source apportionment using chemical mass balance (CMB) receptor modeling. Analyses of the organic molecular markers revealed that vehicle emission, coal combustion, biomass burning, meat cooking and natural gas combustion were the major contributors to organic carbon (OC) in PM2.5. The vehicle emission dominated the sources contributing to OC in spring at four sampling sites. During wintertime, the coal combustion had highest contribution to OC at BTH site, while the major source contributing to OC at YRD and PRD sites was vehicle emission. In addition, the relative contributions of different emission sources to PM2.5 mass at a specific location site and in a specific season revealed seasonal and spatial variations across all four sampling locations. The largest contributor to PM2.5 mass was secondary sulfate (14-17%) in winter at the four sites. The vehicle emission was found to be the major source (14-21%) for PM2.5 mass at PRD site. The secondary ammonium has minor variation (4-5%) across the sites, confirming the influences of regional emission sources on these sites. The distinct patterns of seasonal and spatial variations of source apportionment observed in this study were consistent with the findings in our previous paper based upon water-soluble ions and carbonaceous fractions. This makes it essential for the local government to make season- and region-specific mitigation strategies for abating PM2.5 pollution in China.

  3. Continuous vertical aerosol profiling with a multi-wavelength Raman polarization lidar over the Pearl River Delta, China

    Directory of Open Access Journals (Sweden)

    B. Heese

    2017-06-01

    Full Text Available A dataset of particle optical properties of the highly polluted atmosphere over the Pearl River Delta (PRD, Guangzhou, China, is presented in this paper. The data were derived from the measurements of a multi-wavelength Raman and depolarization lidar PollyXT and a co-located AERONET sun photometer. The measurement campaign was conducted from November 2011 to mid-June 2012. These are the first Raman lidar measurements in the PRD that lasted for several months. A mean value of aerosol optical depth (AOD of 0.54 ± 0.33 was observed by the sun photometer at 500 nm in the polluted atmosphere over this megacity for the whole measurement period. The lidar profiles frequently show lofted aerosol layers, which reach altitudes of up to 2 to 3 km and, especially during the spring season, up to 5 km. These layers contain between 12 and 56 % of the total AOD, with the highest values in spring. The aerosol types in these lofted layers are classified by their optical properties. The observed lidar ratio values range from 30 to 80 sr with a mean value of 48.0 ± 10.7 sr at 532 nm. The linear particle depolarization ratio at 532 nm lies mostly below 5 %, with a mean value of 3.6 ± 3.7 %. The majority of the Ångström exponents lie between 0.5 and 1.5, indicating a mixture of fine- and coarse-mode aerosols. These results reveal that mostly urban pollution particles mixed with particles produced from biomass and industrial burning are present in the atmosphere above the Pearl River Delta. Trajectory analyses show that these pollution mixtures arise mainly from local and regional sources.

  4. Continuous vertical aerosol profiling with a multi-wavelength Raman polarization lidar over the Pearl River Delta, China

    Science.gov (United States)

    Heese, Birgit; Baars, Holger; Bohlmann, Stephanie; Althausen, Dietrich; Deng, Ruru

    2017-06-01

    A dataset of particle optical properties of the highly polluted atmosphere over the Pearl River Delta (PRD), Guangzhou, China, is presented in this paper. The data were derived from the measurements of a multi-wavelength Raman and depolarization lidar PollyXT and a co-located AERONET sun photometer. The measurement campaign was conducted from November 2011 to mid-June 2012. These are the first Raman lidar measurements in the PRD that lasted for several months. A mean value of aerosol optical depth (AOD) of 0.54 ± 0.33 was observed by the sun photometer at 500 nm in the polluted atmosphere over this megacity for the whole measurement period. The lidar profiles frequently show lofted aerosol layers, which reach altitudes of up to 2 to 3 km and, especially during the spring season, up to 5 km. These layers contain between 12 and 56 % of the total AOD, with the highest values in spring. The aerosol types in these lofted layers are classified by their optical properties. The observed lidar ratio values range from 30 to 80 sr with a mean value of 48.0 ± 10.7 sr at 532 nm. The linear particle depolarization ratio at 532 nm lies mostly below 5 %, with a mean value of 3.6 ± 3.7 %. The majority of the Ångström exponents lie between 0.5 and 1.5, indicating a mixture of fine- and coarse-mode aerosols. These results reveal that mostly urban pollution particles mixed with particles produced from biomass and industrial burning are present in the atmosphere above the Pearl River Delta. Trajectory analyses show that these pollution mixtures arise mainly from local and regional sources.

  5. Thermal conductivity of soils with heavy metals concentration from the Niger Delta region of Nigeria

    Institute of Scientific and Technical Information of China (English)

    AKINYEMI O.D.; OLOWOFELA J.A.; AKINLADE O.O.; AKANDE O.O.

    2006-01-01

    This paper presents the characteristic thermal and chemical properties of some surface soil samples from the oil-producing regions of Nigeria. A microprocessor-based thermal analyzer was used to determine the thermal conductivity while spectrophotometric procedure was employed to conduct the heavy metal concentration analysis. Thermal conductivity values were compared with heavy metal concentrations in each soil sample. The values of lead and cadmium and their respective measured thermal conductivities were highly correlated, with their correlation coefficients both greater than 0.900, while other metals showed no correlation.

  6. Spin asymmetry for the $^{16}$O($\\overrightarrow{gamma},\\pi\\overline{}$p) reaction in the $\\Delta$(1232) region within an effective Lagrangian approach

    CERN Document Server

    Fernandez-Ramirez, C; Vignote, J R; Udias, J M

    2008-01-01

    The spin asymmetry of the photon in the exclusive A(gamma,pi N)A-1 reaction is computed employing a recently developed fully relativistic model based on elementary pion production amplitudes that include a consistent treatment of the spin-3/2 nucleon resonances. We compare the results of this model to the only available data on Oxygen [Phys. Rev. C 61 (2000) 054609] and find that, contrary to other models, the predicted spin asymmetry compares well to the available experimental data in the Delta(1232) region. Our results indicate that no major medium modifications in the Delta(1232) properties are needed in order to describe the measured spin asymmetries.

  7. Precipitation Chemistry and Occurrence of Acid Rain over the Oil-Producing Niger Delta Region of Nigeria

    Directory of Open Access Journals (Sweden)

    John Kanayo Chukwu Nduka

    2010-01-01

    Full Text Available This study investigated the nitrate, sulfate, total dissolved solid (TDS, electrical conductivity, total hardness (TH, and bicarbonates of rainwater samples collected from Warri and Port Harcourt between April–June, July–August, and September–October of 2005 and 2006 to depict onset of rainy season, mid-rainy season, and end of rainy season for the two major crude oil–producing cities of the Niger Delta region of Nigeria (although Port Harcourt is also noted for non-oil manufacturing industries. The same was done in Awka, a non-oil producing city in the hinterland of southeastern Nigeria. In each of the cities, rain samples were collected from three points in a triangular equilibrium using a clean plastic basin fastened to a table 2 m above ground level and 115 m away from tall buildings and trees. The parameters were determined after filtering, using their respective standard methods. Averages of 1.50, 1.81, 1.13 and 2.14, 1.50, 1.86 mg/l of nitrate for April–June, July–August, and September–October were recorded for Warri in 2005 and 2006, respectively. While 15.21, 3.23, 22.31 and 20.89, 9.96, and 14.27 mg/l were recorded in Port Harcourt. Sulfate levels for Warri and Port Harcourt for the same periods are follows: 1.38, 1.88, 1.06, 1.50, 1.43, 1.50 and 2.64, 1.15, 5.88, 4.73, 1.90, 1.55 mg/l, respectively. Nitrate levels were higher than sulfate. Other parameters include TDS (5.44, 4.79, 3.30 and 7.63, 3.69, 2.56 mg/l for Warri in 2005 and 2006; 12.57, 2.07, 25.214 and 28.87, 6.73, 7.80 mg/l for Port Harcourt for the same periods. Other parameters also varied in that order for the 2 years in same cities. Crude oil exploration and gas flaring in the Niger Delta, and multiplicity of cottage industries in Awka, impacted on the inorganic ion pollution of the rainwater. This may have public health implications in the region.

  8. KARAKTERISASI SIFAT-SIFAT BIOKIMIA EKSTRAK KASAR LIPASE EKSTRASELULER BAKTERI Azospirillum sp.PRD1

    Directory of Open Access Journals (Sweden)

    Santi Nur Handayani

    2011-11-01

    Full Text Available Enzim lipase mempunyai peranan penting dalam katalis berbagai reaksi industri satu diantaranya pembuatan flavor melalui reaksi esterifikasi. Lipase adalah biokatalis yang berperan besar dalam aplikasi bioteknologi, seperti dalam sintesis biopolimer, biodiesel, produksi obat, dan produksi flavor. Peningkatan penggunaan lipase untuk industri mendorong dilakukan penelitian untuk mendapatkan sumber-sumber lipase baru. Sumber lipase yang potensial salah satunya adalah bakteri Azospirillum sp.PRD1 dari isolat lokal Laboratorium Mikrobiologi, Fakultas Biologi Universitas Jenderal Soedirman. Tujuan penelitian adalah untuk mendapatkan ekstrak kasar lipase dan menentukan karakteristik sifat-sifat biokimiawinya. Metode yang digunakan antara lain peremajaan bakteri Azospirillum sp.PRD1, dan produksi inokulum, penentuan waktu produksi optimum dan fase pertumbuhan bakteri, ekstraksi dan produksi ekstrak kasar lipase dan penentuan karakteristik sifat-sifat biokimiawinya. Hasil penelitian diperoleh ekstrak kasar lipase dari inokulum berumur 7 jam dan medium produksi dengan induser minyak zaitun yang diinkubasi selama 3 jam memiliki aktivitas spesifik 7,0547 Unit/mg. Lipase ekstrak kasar optimum pada pH 7, suhu 40 oC dan waktu inkubasi selama 25 menit. Lipase merupakan metaloenzim dengan kofaktor Zn2+ , Mn2+, Hg2+, Ca2+, Co2+ and Mg2+.

  9. Hourly peak concentration measuring the PM2.5-mortality association: Results from six cities in the Pearl River Delta study

    Science.gov (United States)

    Lin, Hualiang; Ratnapradipa, Kendra; Wang, Xiaojie; Zhang, Yonghui; Xu, Yanjun; Yao, Zhenjiang; Dong, Guanghui; Liu, Tao; Clark, Jessica; Dick, Rebecca; Xiao, Jianpeng; Zeng, Weilin; Li, Xing; Qian, Zhengmin (Min); Ma, Wenjun

    2017-07-01

    Compared with daily mean concentration of air pollution, hourly peak concentration may be more directly relevant to the acute health effects due to the high concentration levels, however, few have analyzed the acute mortality effects of hourly peak levels of air pollution. We examined the associations of hourly peak concentration of fine particulate matter air pollution (PM2.5) with mortality in six cities in Pearl River Delta, China. We used generalized additive Poisson models to examine the associations with adjustment for potential confounders in each city. We further applied random-effects meta-analyses to estimate the regional overall effects. We further estimated the mortality burden attributable to hourly peak and daily mean PM2.5. We observed significant associations between hourly peak PM2.5 and mortality. Each 10 μg/m3 increase in 4-day averaged (lag03) hourly peak PM2.5 corresponded to a 0.9% [95% confidence interval (CI): 0.7%, 1.1%] increase in total mortality, 1.2% (95% CI: 1.0%, 1.5%) in cardiovascular mortality, and 0.7% (95% CI: 0.2%, 1.1%) in respiratory mortality. We observed a greater mortality burden using hourly peak PM2.5 than daily mean PM2.5, with an estimated 12915 (95% CI: 9922, 15949) premature deaths attributable to hourly peak PM2.5, and 7951 (95% CI: 5067, 10890) to daily mean PM2.5 in the Pearl River Delta (PRD) region during the study period. This study suggests that hourly peak PM2.5 might be one important risk factor of mortality in PRD region of China; the finding provides important information for future air pollution management and epidemiological studies.

  10. Characteristics of Aerosol Ionic Compositions in Summer 2003 at Lin'an of Yangtze Delta Region

    Institute of Scientific and Technical Information of China (English)

    YAN Peng; ZHANG Yangmei; YANG Dongzhen; TANG Jie; ZHOU Xiuji

    2006-01-01

    With the size-resolved aerosol mass and ion composition data obtained at Lin'an regional atmospheric pollution monitoring station in July 2003, the size distributions of aerosol mass and ionic components, and the correlations between major ion pairs were analyzed. The primary results indicate that in the period of in-situ measurement, the aerosols are mainly composed of fine particles. The mass of aerosols with size less than 2.1 μm accounts for 66% of the total mass of all size ranges, in which about 50% of the mass is contributed by the particles with size less than 0.65 μm. Similar to the size distributions of aerosol mass,the water-soluble ions are mainly concentrated in the size range of <0.65μm, accounting for about 77% of the sum of analyzed ions, and the ions within the range of <2.1 μm reach 88%. The sulfate, ammonium,and potassium are the dominant ionic components in fine particles (particle size less than 2.1 μm). Ion correlation analysis suggests that the sulfates in fine particles are mostly in the compounds of (NH4)2SO4,Na2SO4, and K2SO4, but for submicron particles the sulfates are mainly in the form of (NH4)2SO4.

  11. Mapping Social Vulnerability to Air Pollution: A Case Study of the Yangtze River Delta Region, China

    Directory of Open Access Journals (Sweden)

    Yi Ge

    2017-01-01

    Full Text Available Many frequent and severe air pollution incidents have emerged across the vast parts of China recently. The identification of factors and mapping social vulnerability has become extremely necessary for environmental management and sustainable development. However, studies associating social vulnerability with air pollution remain sparse. With reference to research achievements of social vulnerability, this study made a new trial regarding social vulnerability assessment to air pollution. With the projection pursuit cluster (PPC model, the top three factors contributing to social vulnerability index (SVI were discovered and SVI and SVI dimensions (susceptibility, exposure, and adaptability were evaluated. Results revealed that adaptability values are higher than susceptibility and exposure values. SVI is in a poor condition as, for the whole region, most values belong to the high-medium level. High SVI values mainly appear in the northern and the southern ends of study area. SVI in Shanghai is lower than in Jiangsu and Zhejiang provinces. On the scale of prefecture-level city, it can be found that the low-value centers of SVI always occurred in urban core areas. The spatial variation and inequality in social vulnerability provide policy-makers a scientific basis for air pollution prevention and sustainable management.

  12. Photofission of actinide and pre-actinide nuclei in the quasideuteron and delta energy regions

    CERN Document Server

    Berman, B L; Cole, P L; Dodge, W R; Feldman, G; Sanabria, J C; Kolb, N; Pywell, R E; Vogt, J; Nedorezov, V; Sudov, A; Kezerashvili, G Ya

    1999-01-01

    The photofission cross sections for the actinide nuclei sup 2 sup 3 sup 2 Th, sup 2 sup 3 sup 3 sup , sup 2 sup 3 sup 5 sup , sup 2 sup 3 sup 8 U, and sup 2 sup 3 sup 7 Np have been measured from 68 to 264 MeV and those for the pre-actinide nuclei sup 1 sup 9 sup 7 Au and sup N sup A sup T Pb from 122 to 222 MeV at the Saskatchewan Accelerator Laboratory, using monoenergetic tagged photons and novel parallel-plate avalanche detectors for the fission fragments. The aim of the experiment was to obtain a comprehensive and self-consistent data set and to investigate previous anomalous results in this energy region. The fission probability for transuranic nuclei is expected to be close to unity here. However, important discrepancies have been confirmed for sup 2 sup 3 sup 7 Np and sup 2 sup 3 sup 2 Th, compared with sup 2 sup 3 sup 8 U, which have serious implications for the inferred total photoabsorption strengths, and hence call into question the 'Universal Curve' for photon absorption at these energies. High-s...

  13. Estimates of anthropogenic halocarbon emissions based on its measured ratios relative to CO in the Pearl River Delta

    Science.gov (United States)

    Shao, M.; Huang, D. K.; Gu, D. S.; Lu, S. H.; Chang, C. C.; Wang, J.-L.

    2011-01-01

    Using a GC/FID/MS system, we analyzed the mixing ratio levels of 16 halocarbon species in more than 100 air samples collected in 2004 from the Pearl River Delta (PRD) region of southern China. The results revealed elevated regional mixing ratios for most halocarbons, especially for HClC = CCl2 (trichloroethylene, TCE), CH2Cl2 (dichloromethane, DCM), CH3Br (bromomethane), HCFC-22, CHCl3 (trichloromethane), CCl4 (tetrachloromethane), Cl2C = CCl2 (perchloroethylene, PCE), CH3CCl3 (methyl chloroform, MCF), and CFC-12. Comparisons were done with the data from TRACE-P and ALE/GAGE/AGAGE experiments, we found that the large variability in concentrations (relative standard deviation ranged from 9.31% to 96.55%) of the halocarbons suggested substantial local emissions from the PRD region in 2004. Correlations between the mixing ratio of each species and carbon monoxide (CO) were examined, and then each emission of halocarbon was quantified based on scaling the optimized CO emission inventory with the slope of the regression line fitted to each species relative to CO. The calculated results revealed that mass of CH2Cl2 (7.0 Gg), CH3CCl3 (6.7 Gg), and Cl2C = CCl2 (2.3 Gg) accounted for about 62.9% of total emissions, suggesting a significant contribution to halocarbon emissions from solvent use in the PRD region. Emissions of HCFC-22 (3.5 Gg), an alternative refrigerant to chlorofluorocarbons (CFCs), were about 2.3 times greater than those of CFC-12 (1.6 Gg). CFC-12 and HCFC-22 accounted for 21.5% of total emissions of halocarbons, so that the refrigerant would be the second largest source of halocarbons. However, the ratio approach found only minor emissions of other CFCs, such as CFC-11, and levels of CFC-114 and CFC-113 were close to zero. Emissions of other anthropogenic halocarbons, such as CCl4, CHCl3, CH3Br, and CH3Cl, were also estimated. Where possible, the emissions estimated from the measured ratios were compared with results from source inventory techniques, we

  14. The forecasting research of early warning systems for atmospheric pollutants: A case in Yangtze River Delta region

    Science.gov (United States)

    Song, Yiliao; Qin, Shanshan; Qu, Jiansheng; Liu, Feng

    2015-10-01

    The issue of air quality regarding PM pollution levels in China is a focus of public attention. To address that issue, to date, a series of studies is in progress, including PM monitoring programs, PM source apportionment, and the enactment of new ambient air quality index standards. However, related research concerning computer modeling for PM future trends estimation is rare, despite its significance to forecasting and early warning systems. Thereby, a study regarding deterministic and interval forecasts of PM is performed. In this study, data on hourly and 12 h-averaged air pollutants are applied to forecast PM concentrations within the Yangtze River Delta (YRD) region of China. The characteristics of PM emissions have been primarily examined and analyzed using different distribution functions. To improve the distribution fitting that is crucial for estimating PM levels, an artificial intelligence algorithm is incorporated to select the optimal parameters. Following that step, an ANF model is used to conduct deterministic forecasts of PM. With the identified distributions and deterministic forecasts, different levels of PM intervals are estimated. The results indicate that the lognormal or gamma distributions are highly representative of the recorded PM data with a goodness-of-fit R2 of approximately 0.998. Furthermore, the results of the evaluation metrics (MSE, MAPE and CP, AW) also show high accuracy within the deterministic and interval forecasts of PM, indicating that this method enables the informative and effective quantification of future PM trends.

  15. Household possession, use and non-use of treated or untreated mosquito nets in two ecologically diverse regions of Nigeria – Niger Delta and Sahel Savannah

    Directory of Open Access Journals (Sweden)

    Otsemobor Peju

    2009-02-01

    Full Text Available Abstract Background Current use of treated mosquito nets for the prevention of malaria falls short of what is expected in sub-Saharan Africa (SSA, though research within the continent has indicated that the use of these commodities can reduce malaria morbidity by 50% and malaria mortality by 20%. Governments in sub-Sahara Africa are investing substantially in scaling-up treated mosquito net coverage for impact. However, certain significant factors still prevent the use of the treated mosquito nets, even among those who possess them. This survey examines household ownership as well as use and non-use of treated mosquito nets in Sahel Savannah and Niger Delta regions of Nigeria. Methodology This survey employed cross-sectional survey to collect data from households on coverage and use of mosquito nets, whether treated or not. Fever episodes in previous two weeks among children under the age of five were also recorded. The study took place in August 1 – 14 2007, just five months after the March distribution of treated mosquito nets, coinciding with the second raining period of the year and a time of high malaria transmission during the wet season. EPI INFO version 2003 was used in data analysis. Results The survey covered 439 households with 2,521 persons including 739 under-fives, 585 women in reproductive age and 78 pregnant women in Niger Delta Region and Sahel Savannah Region. Of the 439 HHs, 232 had any mosquito nets. Significantly higher proportion of households in the Niger Delta Region had any treated or untreated mosquito nets than those in the Sahel Savannah Region. In the Niger Delta Region, the proportion of under-fives that had slept under treated nets the night before the survey exceeded those that slept under treated nets in the Sahel Savannah Region. Children under the age of five years in the Niger Delta Region were four times more likely to sleep under treated nets than those in the Sahel Savannah Region. Conclusion This study

  16. The impact of synoptic circulation on air quality and pollution-related human health in the Yangtze River Delta region.

    Science.gov (United States)

    Liao, Zhiheng; Gao, Meng; Sun, Jiaren; Fan, Shaojia

    2017-12-31

    PM2.5 and O3 pollution are of concern for the Yangtze River Delta (YRD) region due to their adverse impact on human health. In conjunction with a complex distribution of emission sources, the synoptic circulation conditions control the temporal and spatial variability of air pollution levels and hence the pollution-related health burdens. In this study, a long-term synoptic circulation catalogue is developed by applying the automated Lamb weather type method to the ECMWF mean sea level pressure reanalysis for the YRD region during 2013-2016. Ten typical circulation types are examined in relation to the transport pathways and diffusion conditions, and then multi-site surface observations of PM2.5 and O3 are composited for different circulation conditions. The results show that each circulation type is characterized with distinct air mass origin, diffusion condition and air quality level. The anticyclonic type (Type A) corresponds to the highest regional PM2.5 concentration (68.5μg/m(3)) due to the subsidence flow and long-range transport, while the westerly types (Types SW, W and NW) correspond to the higher regional maximum daily 8-h running average O3 (MDA8 O3) concentration (>100μg/m(3)) due to favorable local meteorological conditions. Regional transport causes an east-high and west-low PM2.5 distribution in westerly types but a west-high and east-low PM2.5 distribution in easterly types (Types SE, E and NE). In contrast, nearly all the types show an east-high and west-low O3 distribution, suggesting the predominated impacts of precursor emissions. By using established exposure-response functions, the health impact assessment (HIA) shows that Type W poses the greatest public health risk with mean daily excess mortality of 77.3 (95% CI: 61.9, 92.6) deaths and O3 pollution accounts for approximately 70% of this health burden. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Contamination profiles of perfluoroalkyl substances in five typical rivers of the Pearl River Delta region, South China.

    Science.gov (United States)

    Pan, Chang-Gui; Ying, Guang-Guo; Liu, You-Sheng; Zhang, Qian-Qian; Chen, Zhi-Feng; Peng, Feng-Jiao; Huang, Guo-Yong

    2014-11-01

    A survey on contamination profiles of eighteen perfluoroalkyl substances (PFASs) was performed via high performance liquid chromatography-tandem mass spectrometry for surface water and sediments from five typical rivers of the Pearl River Delta region, South China in summer and winter in 2012. The total concentrations of the PFASs in the water phase of the five rivers ranged from 0.14 to 346.72 ng L(-1). The PFAS concentrations in the water phase were correlated positively to some selected water quality parameters such as chemical oxygen demand (COD) (0.7913) and conductivity (0.5642). The monitoring results for the water samples showed significant seasonal variations, while those for the sediment samples showed no obvious seasonal variations. Among the selected 18 PFASs, perfluorooctane sulfonic acid (PFOS) was the dominant PFAS compound both in water and sediment for two seasons with its maximum concentration of 320.5 ng L(-1) in water and 11.4 ng g(-1) dry weight (dw) in sediment, followed by perfluorooctanoic acid (PFOA) with its maximum concentration of 26.48 ng L(-1) in water and 0.99 ng g(-1) dw in sediment. PFOS and PFOA were found at relatively higher concentrations in the Shima River and Danshui River than in the other three rivers (Xizhijiang River, Dongjiang River and Shahe River). The principal component analysis for the PFASs concentrations in water and sediment separated the sampling sites into two groups: rural and agricultural area, and urban and industrial area, suggesting the PFASs in the riverine environment were mainly originated from industrial and urban activities in the region.

  18. Nesting success of geese in the coastal tundra region of the Yukon-Kuskokwim Delta, 1985 final report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Progress was made in 1985 towards development of sampling methods to provide an unbiased estimate of annual production by geese nesting on the Yukon-Kuskokwim Delta,...

  19. Nesting success of geese in the coastal tundra region of the Yukon-Kuskokwim Delta: 1986 field report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Goose nesting success on the YK Delta in 1986 increased over 1984 and 1985. Environmental conditions were close to average in spite of a cool and prolonged spring....

  20. Nesting success of geese in the coastal tundra region of the Yukon-Kuskokwim Delta: 1985 field report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Goose production on the YK Delta in 1985 remained depressed. Environmental conditions of the late spring were partially responsible, but do not fully explain...

  1. Modeling of the anthropogenic heat flux and its effect on air quality over the Yangtze River Delta region, China

    Directory of Open Access Journals (Sweden)

    M. Xie

    2015-11-01

    Full Text Available Anthropogenic heat (AH emissions from human activities caused by urbanization can affect the city environment. Based on the energy consumption and the gridded demographic data, the spatial distribution of AH emission over the Yangtze River Delta (YRD region is estimated. Meanwhile, a new method for the AH parameterization is developed in the WRF/Chem model, which incorporates the gridded AH emission data with the seasonal and the diurnal variations into the simulations. By running this upgraded WRF/Chem for two typical months in 2010, the impacts of AH on the meteorology and air quality over the YRD region are studied. The results show that the AH fluxes over YRD have been growing in recent decades. In 2010, the annual mean values of AH over Shanghai, Jiangsu and Zhejiang are 14.46, 2.61 and 1.63 W m−2 respectively, with the high values of 113.5 W m−2 occurring in the urban areas of Shanghai. These AH emissions can significantly change the urban heat island and urban-breeze circulations in the cities of the YRD region. In Shanghai, 2 m air temperature increases by 1.6 °C in January and 1.4 °C in July, the planetary boundary layer height rises up by 140 m in January and 160 m in July, and 10 m wind speed is enhanced by 0.7 m s−1 in January and 0.5 m s−1 in July, with higher increment at night. And the enhanced vertical movement can transport more moisture to higher levels, which causes the decrease of water vapor at the ground level and the increase in the upper PBL, and thereby induces the accumulative precipitation to increase by 15–30 % over the megacities in July. The adding AH can impact the spatial and vertical distributions of the simulated pollutants as well. The concentrations of primary air pollutants decrease near surface and increase at the upper levels, due mainly to the increases of PBLH, surface wind speed and upward air vertical movement. But surface O3 concentrations increase in the urban areas, with maximum changes

  2. The scattering polarization of the Ly-alpha lines of H I and He II taking into account PRD and J-state interference effects

    CERN Document Server

    Belluzzi, Luca; Stepan, Jiri

    2012-01-01

    Recent theoretical investigations have pointed out that the cores of the Ly-alpha lines of H I and He II should show measurable scattering polarization signals when observing the solar disk, and that the magnetic sensitivity, through the Hanle effect, of such linear polarization signals is suitable for exploring the magnetism of the solar transition region. Such investigations were carried out in the limit of complete frequency redistribution (CRD) and neglecting quantum interference between the two upper J-levels of each line. Here we relax both approximations and show that the joint action of partial frequency redistribution (PRD) and J-state interference produces much more complex fractional linear polarization (Q/I) profiles, with large amplitudes in their wings. Such wing polarization signals turn out to be very sensitive to the temperature structure of the atmospheric model, so that they can be exploited for constraining the thermal properties of the solar chromosphere. Finally, we show that the approxi...

  3. Infrastructure and Health Care Services in the Niger Delta Region of Nigeria: A Case Study of Physical Amenities in the Primary Health Care System in Delta State

    Directory of Open Access Journals (Sweden)

    Omuta GED

    2016-01-01

    Full Text Available Background: One of the spin-off effects of the urban-based medical services established by the colonial administration was the total neglect of rural communities. Those that existed lacked infrastructure. Even fifty years after independence, this dichotomy has persisted and become more pronounced. The objective of this study is to examine the state of infrastructure in the primary health care centres in Delta State, Nigeria. Methodology: The study was a survey of the infrastructure of all the PHC centres in nine local government areas; three from each of the three senatorial districts. The facilities covered were sources of water supply, sources of electricity, number of functional beds and type of communication facilities. The field date were cleaned up, processed and analysed using SPSS 10.0. Focus group discussions and key informant interviews were also conducted. In order to make the findings policy-relevant, a project steering committee made of researchers and decision makers and a project management committee made of representatives of decision makers, care providers, care seekers and other stakeholders were se up and integrated into the study. Results: There were varying degrees of infrastructural deficiencies. 34.22 per cent of the PHCs had no access to safe water; 51.33 per cent were not connected to the national electricity grid; and 34.22 per cent of the available beds and 40.89 per cent no means of communication whatsoever. Conclusion: Field data and perspectives of stakeholders revealed that the major cause of infrastructural deficiencies was insufficient funding, lopsided allocation of resources and official corruption. Correspondingly, increased and sustained funding; prioritized allocation of resources and targeted upgrading of facilities, were recommended.

  4. Reflectance-difference study near the E{sub 1} and E{sub 1} + {delta}{sub 1} transition regions of CdTe

    Energy Technology Data Exchange (ETDEWEB)

    Molina C, J Rafael [Centro de Investigaciones en Optica, AC, Loma del Bosque 115, Colonia Lomas del Campestre, CP 37150 Leon, Guanajuato (Mexico); Espinosa-Luna, Rafael [Centro de Investigaciones en Optica, AC, Loma del Bosque 115, Colonia Lomas del Campestre, CP 37150 Leon, Guanajuato (Mexico)

    2005-01-07

    We report on a study of the experimental reflectance-difference (RD) line shape for CdTe near the E{sub 1} and E{sub 1} + {delta}{sub 1} spectral regions. A clear reflectivity component, as a major contribution near the E{sub 1} and E{sub 1} + {delta}{sub 1} spectral regions, to the measured RD CdTe line shape is found. No derivative-like, {epsilon} -like or 1/{epsilon} -like line shapes are observed for our sample. Results suggest that the experimental RD spectra cannot be explained by considering an anisotropic film on the surface of the material nor by a dislocation-induced piezo-optic effect.

  5. HIV infection, risk factors, and preventive services utilization among female sex workers in the Mekong Delta Region of Vietnam.

    Directory of Open Access Journals (Sweden)

    Bach Xuan Tran

    Full Text Available BACKGROUND: Risk behaviors among female sex workers (FSW are considerable drivers of HIV infections in Vietnam, especially transmission between high-risk and low-risk groups. We assessed HIV prevalence and its correlates among FSWs, and the use of preventive services among this community in the Mekong Delta region, southern Vietnam. METHODS: A cross-sectional survey of 1,999 FSWs was carried out in five provinces including Ben Tre, Hau Giang, Kien Giang, Tien Giang, and Vinh Long between June, 2006 and June, 2007. We interviewed participants face-to-face in order to elicit information about their lives and potential risk factors, and we tested their sera to determine their HIV status. We then performed multivariate logistic regression analyses to investigate factors associated with HIV infection. RESULTS: Seventeen percent of the participating FSWs were street-based sex workers (SSWs and the rest (83% were entertainment establishment-based sex workers (ESWs. Unprotected sex with regular and casual clients in the past month was frequent among study participants (40.5% and 33.5% respectively. However, few respondents (1.3% had ever injected drugs. Only 2.1% (95% confidence interval (CI: 1.6%-2.8% of FSWs were found to be infected with HIV. HIV prevalence among SSWs was greater than among ESWs (3.8% vs. 1.8%, p = 0.02, respectively. Increased risk for HIV infection was significantly associated with the number of clients per month (adjusted odd ratio (aOR = 2.65, 95% CI: 1.26-5.59. CONCLUSIONS: Interventions to reduce unsafe sex and drug injection, and to increase uptake of HIV testing among FSWs are necessary. Differences in HIV prevalence and its correlates by type of sex work emphasize the importance of constrained contexts in shaping risk behaviors among FSWs; that should be considered in designing HIV prevention programs.

  6. Spatial and seasonal variations of atmospheric organic carbon and elemental carbon in Pearl River Delta Region, China

    Science.gov (United States)

    Cao, J. J.; Lee, S. C.; Ho, K. F.; Zou, S. C.; Fung, Kochy; Li, Y.; Watson, John G.; Chow, Judith C.

    The concentrations of organic carbon (OC) and elemental carbon (EC) in atmospheric particles were investigated at eight sites in four cities (Hong Kong, Guangzhou, Shenzhen and Zhuhai) of the Pearl River Delta Region (PRDR), China, during winter and summer 2002. The comparison of summer and winter results was made in order to investigate spatial and seasonal variations. PM 2.5 and PM 10 samples were collected on pre-fired quartz filters with mini-volume samplers and analyzed by the thermal optical reflectance (TOR) method following the Interagency Monitoring of PROtected Visual Environments (IMPROVE) protocol. During summer, the average OC and EC concentrations in PM 2.5 were 9.2 and 4.1 μg m -3, while those in PM 10 were 12.3 and 5.2 μg m -3. Carbonaceous aerosol accounted for 38.0% of the PM 2.5 and 32.9% of the PM 10. The daily average OC, EC, PM 2.5 and PM 10 concentrations in PRDR were higher in winter than in summer. The average OC/EC ratio was 2.5 for PM 2.5 and PM 10, suggesting the presence of secondary organic aerosols. The estimated secondary organic carbons in PM 2.5 and PM 10 were 4.1 and 5.6 μg m -3, respectively. The OC and EC were found to be correlated in winter (correlation coefficient r=0.82) and summer ( r=0.64), which implied that motor vehicle sources contributed to the ambient carbonaceous particles. The distribution of eight carbon fractions in OC and EC at eight sites was first reported in ambient samples in Asia, which also indicated that motor vehicle exhaust was the dominant contributor to carbonaceous particles.

  7. Superscaling and Charge-Changing Neutrino Scattering from Nuclei in the $\\boldsymbol \\Delta$-Region beyond the Relativistic Fermi Gas Model

    CERN Document Server

    Ivanov, M V; Caballero, J A; Antonov, A N; de Guerra, E Moya; Gaidarov, M K

    2008-01-01

    The superscaling analysis using the scaling function obtained within the coherent density fluctuation model is extended to calculate charge-changing neutrino and antineutrino scattering on $^{12}$C at energies from 1 to 2 GeV not only in the quasielastic but also in the delta excitation region. The results are compared with those obtained using the scaling functions from the relativistic Fermi gas model and from the superscaling analysis of inclusive scattering of electrons from nuclei.

  8. Top-down estimates of benzene and toluene emissions in the Pearl River Delta and Hong Kong, China

    Science.gov (United States)

    Fang, Xuekun; Shao, Min; Stohl, Andreas; Zhang, Qiang; Zheng, Junyu; Guo, Hai; Wang, Chen; Wang, Ming; Ou, Jiamin; Thompson, Rona L.; Prinn, Ronald G.

    2016-03-01

    Benzene (C6H6) and toluene (C7H8) are toxic to humans and the environment. They are also important precursors of ground-level ozone and secondary organic aerosols and contribute substantially to severe air pollution in urban areas in China. Discrepancies exist between different bottom-up inventories for benzene and toluene emissions in the Pearl River Delta (PRD) and Hong Kong (HK), which are emission hot spots in China. This study provides top-down estimates of benzene and toluene emissions in the PRD and HK using atmospheric measurement data from a rural site in the area, Heshan, an atmospheric transport model, and an inverse modeling method. The model simulations captured the measured mixing ratios during most pollution episodes. For the PRD and HK, the benzene emissions estimated in this study for 2010 were 44 (12-75) and 5 (2-7) Gg yr-1 for the PRD and HK, respectively, and the toluene emissions were 131 (44-218) and 6 (2-9) Gg yr-1, respectively. Temporal and spatial differences between the inversion estimate and four different bottom-up emission estimates are discussed, and it is proposed that more observations at different sites are urgently needed to better constrain benzene and toluene (and other air pollutant) emissions in the PRD and HK in the future.

  9. Fabrication of a nanometer thick nitrogen delta doped layer at the sub-surface region of (100) diamond

    Science.gov (United States)

    Chandran, Maneesh; Michaelson, Shaul; Saguy, Cecile; Hoffman, Alon

    2016-11-01

    In this letter, we report on the proof of a concept of an innovative delta doping technique to fabricate an ensemble of nitrogen vacancy centers at shallow depths in (100) diamond. A nitrogen delta doped layer with a concentration of ˜1.8 × 1020 cm-3 and a thickness of a few nanometers was produced using this method. Nitrogen delta doping was realized by producing a stable nitrogen terminated (N-terminated) diamond surface using the RF nitridation process and subsequently depositing a thin layer of diamond on the N-terminated diamond surface. The concentration of nitrogen on the N-terminated diamond surface and its stability upon exposure to chemical vapor deposition conditions are determined by x-ray photoelectron spectroscopy analysis. The SIMS profile exhibits a positive concentration gradient of 1.9 nm/decade and a negative gradient of 4.2 nm/decade. The proposed method offers a finer control on the thickness of the delta doped layer than the currently used ion implantation and delta doping techniques.

  10. Delta-associated molluscan life and death assemblages in the northern Adriatic Sea: Implications for paleoecology, regional diversity and conservation.

    Science.gov (United States)

    Weber, Kristina; Zuschin, Martin

    2013-01-15

    Life-death (LD) studies of shelly macrofauna are important to evaluate how well a fossil assemblage can reflect the original living community, but can also serve as a proxy for recent ecological shifts in marine habitats and in practice this has to be distinguished using taphonomic preservation pattern and estimates of time-averaging. It remains to be rigorously evaluated, however, how to distinguish between sources of LD disagreement. In addition, death assemblages (DAs) also preserve important information on regional diversity which is not available from single censuses of the life assemblages (LAs). The northern Adriatic Sea is an ecosystem under anthropogenic pressure, and we studied the distribution and abundance of living and dead bivalve and gastropod species in the physically stressful environments (tidal flat and shallow sublittoral soft bottoms) associated with the delta of the Isonzo River (Gulf of Trieste). Specifically we evaluated the fidelity of richness, evenness, abundance, habitat discrimination and beta diversity. A total of 10,740 molluscs from fifteen tidal flat and fourteen sublittoral sites were analyzed for species composition and distribution of living and dead molluscs. Of 78 recorded species, only eleven were numerically abundant. There were many more dead than living individuals and rarefied species richness in the DA was higher at all spatial scales, but the differences are lower in habitats and in the region than at individual stations. Evenness was always higher in death assemblages, and probably due to temporally more variable LAs the differences are stronger in the sublittoral habitats. Distinct assemblages characterized intertidal and sublittoral habitats, and the distribution and abundance of empty shells generally corresponded to that of the living species. Death assemblages have lower beta diversity than life assemblages, but empty shells capture compositional differences between habitats to a higher degree than living shells

  11. PM2.5 in the Yangtze River Delta, China: Chemical compositions, seasonal variations, and regional pollution events.

    Science.gov (United States)

    Ming, Lili; Jin, Ling; Li, Jun; Fu, Pingqing; Yang, Wenyi; Liu, Di; Zhang, Gan; Wang, Zifa; Li, Xiangdong

    2017-04-01

    Fine particle (PM2.5) samples were collected simultaneously at three urban sites (Shanghai, Nanjing, and Hangzhou) and one rural site near Ningbo in the Yangtze River Delta (YRD) region, China, on a weekly basis from September 2013 to August 2014. In addition, high-frequency daily sampling was conducted in Shanghai and Nanjing for one month during each season. Severe regional PM2.5 pollution episodes were frequently observed in the YRD, with annual mean concentrations of 94.6 ± 55.9, 97.8 ± 40.5, 134 ± 54.3, and 94.0 ± 57.6 μg m(-3) in Shanghai, Nanjing, Hangzhou, and Ningbo, respectively. The concentrations of PM2.5 and ambient trace metals at the four sites showed clear seasonal trends, with higher concentrations in winter and lower concentrations in summer. In Shanghai, similar seasonal patterns were found for organic carbon (OC), elemental carbon (EC), and water-soluble inorganic ions (K(+), NH4(+), Cl(-), NO3(-), and SO4(2-)). Air mass backward trajectory and potential source contribution function (PSCF) analyses implied that areas of central and northern China contributed significantly to the concentration and chemical compositions of PM2.5 in Shanghai during winter. Three heavy pollution events in Shanghai were observed during autumn and winter. The modelling results of the Nested Air Quality Prediction Modeling System (NAQPMS) showed the sources and transport of PM2.5 in the YRD during the three pollution processes. The contribution of secondary species (SOC, NH4(+), NO3(-), and SO4(2-)) in pollution event (PE) periods was much higher than in BPE (before pollution event) and APE (after pollution event) periods, suggesting the importance of secondary aerosol formation during the three pollution events. Furthermore, the bioavailability of Cu, and Zn in the wintertime PM2.5 samples from Shanghai was much higher during the pollution days than during the non-pollution days.

  12. Natural emissions under future climate condition and their effects on surface ozone in the Yangtze River Delta region, China

    Science.gov (United States)

    Xie, Min; Shu, Lei; Wang, Ti-jian; Liu, Qian; Gao, Da; Li, Shu; Zhuang, Bing-liang; Han, Yong; Li, Meng-meng; Chen, Pu-long

    2017-02-01

    The natural emissions of ozone precursors (NOx and VOCs) are sensitive to climate. Future climate change can impact O3 concentrations by perturbing these emissions. To better estimate the variation of natural emissions under different climate conditions and understand its effect on surface O3, we model the present and the future air quality over the Yangtze River Delta (YRD) region by running different simulations with the aid of the WRF-CALGRID model system that contains a natural emission module. Firstly, we estimate the natural emissions at present and in IPCC A1B scenario. The results show that biogenic VOC emission and soil NOx emission over YRD in 2008 is 657 Gg C and 19.1 Gg N, respectively. According to climate change, these emissions in 2050 will increase by 25.5% and 11.5%, respectively. Secondly, the effects of future natural emissions and meteorology on surface O3 are investigated and compared. It is found that the variations in meteorological fields can significantly alter the spatial distribution of O3 over YRD, with the increases of 5-15 ppb in the north and the decreases of -5 to -15 ppb in the south. However, only approximately 20% of the surface O3 increases caused by climate change can be attributed to the natural emissions, with the highest increment up to 2.4 ppb. Finally, Ra (the ratio of impacts from NOx and VOCs on O3 formation) and H2O2/HNO3 (the ratio between the concentrations of H2O2 and HNO3) are applied to study the O3 sensitivity in YRD. The results show that the transition value of H2O2/HNO3 will turn from 0.3 to 0.5 in 2008 to 0.4-0.8 in 2050. O3 formation in the YRD region will be insensitive to VOCs under future climate condition, implying more NOx need to be cut down. Our findings can help us understand O3 variation trend and put forward the reasonable and effective pollution control policies in these famous polluted areas.

  13. Integrated studies of a regional ozone pollution synthetically affected by subtropical high and typhoon system in the Yangtze River Delta region, China

    Science.gov (United States)

    Shu, Lei; Xie, Min; Wang, Tijian; Gao, Da; Chen, Pulong; Han, Yong; Li, Shu; Zhuang, Bingliang; Li, Mengmeng

    2016-12-01

    Severe high ozone (O3) episodes usually have close relations to synoptic systems. A regional continuous O3 pollution episode was detected over the Yangtze River Delta (YRD) region in China during 7-12 August 2013, in which the O3 concentrations in more than half of the cities exceeded the national air quality standard. The maximum hourly concentration of O3 reached 167.1 ppb. By means of the observational analysis and the numerical simulation, the characteristics and the essential impact factors of the typical regional O3 pollution are comprehensively investigated. The observational analysis shows that the atmospheric subsidence dominated by the western Pacific subtropical high plays a crucial role in the formation of high-level O3. The favorable weather conditions, such as extremely high temperature, low relative humidity and weak wind speed, caused by the abnormally strong subtropical high are responsible for the trapping and the chemical production of O3 in the boundary layer. In addition, when the YRD cities are at the front of Typhoon Utor, the periphery circulation of typhoon system can enhance the downward airflows and cause worse air quality. However, when the typhoon system weakens the subtropical high, the prevailing southeasterly surface wind leads to the mitigation of the O3 pollution. The integrated process rate (IPR) analysis incorporated in the Community Multi-scale Air Quality (CMAQ) model is applied to further illustrate the combined influence of subtropical high and typhoon system in this O3 episode. The results show that the vertical diffusion (VDIF) and the gas-phase chemistry (CHEM) are two major contributors to O3 formation. During the episode, the contributions of VDIF and CHEM to O3 maintain the high values over the YRD region. On 10-12 August, the cities close to the sea are apparently affected by the typhoon system, with the contribution of VDIF increasing to 28.45 ppb h-1 in Shanghai and 19.76 ppb h-1 in Hangzhou. In contrast, the cities

  14. Lowstand Turbidites and Delta Systems of the Itararé Group in the Vidal Ramos region (SC, southern Brazil

    Directory of Open Access Journals (Sweden)

    Carla Gimena Puigdomenech

    Full Text Available Turbidites have captioned the attention of sedimentologists during the last decades due their importance as hydrocarbon reservoirs. However, their relationship to delta systems still deserves further studies. This paper presents examples from a late deglacial to early post-glacial deltaic and turbidite strata exposed in the surroundings of Vidal Ramos (Santa Catarina State, Brazil, southern portion of the Paraná Basin. There, the uppermost part of the Mafra Formation and the Rio do Sul Formation onlap the Proterozoic basement and comprises an up to 360 m thick package. It includes (base to top black shales, mass transport deposits (MTD and sandy turbidites (Mafra Formation as well as thin bedded turbidites (tbt, including one interval of black shales and sandy turbidites, overlain by proximal delta front sandstones (Rio do Sul Formation. The analysis of the succession shows two more than 150 m thick coarsening-upwards deltaic successions composed of turbidite sand sheets at their base (prodelta, followed by partially collapsed thin bedded turbidites (delta slope wedge and delta front sandstones. Both turbidite sand-sheets abruptly overlay black shale intervals related to maximum flooding surfaces and therefore record correlative conformities. A detailed stratigraphic section elaborated from the correlation of four logs (1/100 suggests that distal delta front sands includes both thin bedded turbidites and wave reworked sands whereas the proximal delta front was dominated by long-lived underflows (hyperpycnal flows. The succession suggests that the most expressive turbidite beds (base of the delta systems have resulted from relative sea-level falls (early lowstand whereas the thin-bedded turbidites were related to the development of the late lowstand wedge. Black shales represent the transgressive systems tract and HST were not deposited or preserved in the area. High sediment supply associated with lowstand tracts could explain the occasional

  15. Timelike gamma* N -> Delta form factors and Delta Dalitz decay

    CERN Document Server

    Ramalho, G

    2012-01-01

    We extend a covariant model, tested before in the spacelike region for the physical and lattice QCD regimes, to a calculation of the gamma* N -> Delta reaction in the timelike region, where the square of the transfered momentum, q^2, is positive (q^2>0). We estimate the Dalitz decay Delta -> Ne+e- and the Delta distribution mass distribution function. The results presented here can be used to simulate the NN -> NNe+e- reactions at moderate beam kinetic energies.

  16. Regional haemodynamic effects of mu-, delta-, and kappa-opioid agonists microinjected into the hypothalamic paraventricular nuclei of conscious, unrestrained rats.

    Science.gov (United States)

    Bachelard, H; Pître, M

    1995-06-01

    1. The cardiovascular effects of bilateral injection into the hypothalamic paraventricular nuclei of selective mu-, delta-, and kappa-opioid receptor agonists were investigated in conscious, unrestrained Wistar Kyoto rats, chronically instrumented with pulsed Doppler flow probes for measurement of regional haemodynamics. 2. The selective mu-agonist [D-Ala2,MePhe4,Gly5ol]enkephalin (DAMGO), injected bilaterally into the hypothalamic paraventricular nuclei (0.01-1.0 nmol), caused increases in blood pressure, tachycardias, vasoconstriction in renal and superior mesenteric vascular beds and substantial vasodilatation in the hindquarter vascular bed. 3. The administration of increasing doses (0.01-5.0 nmol) of the selective delta-agonist [D-Phe2,5]enkephalin (DPDPE) or the selective kappa-agonist, U50488H into the paraventricular nuclei (PVN) had no significant effect on blood pressure, heart rate, or regional haemodynamics. 4. Together, the present results are further evidence of a role for opioid peptides, especially acting at mu-receptors in the PVN, in the central regulation of the cardiovascular system, whereas a role for opioid peptides, acting at delta- and kappa-receptors in the PVN, seems less obvious from the present results.

  17. Performance comparison among the major healthcare financing systems in six cities of the Pearl River Delta region, mainland China.

    Directory of Open Access Journals (Sweden)

    Martin C S Wong

    Full Text Available BACKGROUND: The healthcare system of mainland China is undergoing drastic reform and the optimal models for healthcare financing for provision of primary care will need to be identified. This study compared the performance indicators of the community health centres (CHCs under different healthcare financing systems in the six cities of the Pearl River Delta region. METHODS: Approximately 300 hypertensive patients were randomly recruited from the computerized chronic disease management records provided by one CHC in each of the six cities in 2011 using a multi-stage cluster random sampling method. The major outcome measures included the treatment rate of hypertension, defined as prescription of ≥ one antihypertensive agent; and the control rate of hypertension, defined as systolic blood pressure levels <140 mmHg and diastolic blood pressure levels <90 mmHg in patients without diabetes mellitus, or <130/80 mmHg among patients with concomitant diabetes. Binary logistic regression analyses were conducted with these two measures as outcome variables, respectively, controlling for patients' socio-demographic variables. The financing system (Hospital- vs. Government- vs. private-funded was the independent variable tested for association with the outcomes. RESULTS: From 1,830 patients with an average age of 65.9 years (SD 12.8, the overall treatment and control rates were 75.4% and 20.2%, respectively. When compared with hospital-funded CHCs, patients seen in the Government-funded (adjusted odds ratio [AOR] 0.462, 95% C.I. 0.325-0.656 and private-funded CHCs (AOR 0.031, 95% C.I. 0.019-0.052 were significantly less likely to be prescribed antihypertensive medication. However, the Government-funded CHC was more likely to have optimal BP control (AOR 1.628, 95% C.I. 1.157-2.291 whilst the privately-funded CHC was less likely to achieve BP control (AOR 0.146, 95% C.I. 0.069-0.310, irrespective of whether antihypertensive drugs were prescribed. CONCLUSIONS

  18. Climatic evolution in the Yangtze Delta region in the late Holocene epoch%长江三角洲全新世气候变迁

    Institute of Scientific and Technical Information of China (English)

    朱诚; 张强

    2006-01-01

    Neolithic site sections, natural sections and other proxy indicators like paleotrees and peat are collected for further understanding the environmental changes during the past 10,000 years in the Yangtze Delta region. The results indicate that cultural interruption in the Yangtze Delta was the result of water expansion induced by climatic changes like more precipitation. For fragile human mitigation to the natural hazards in the Neolithic cultural period, environmental changes usually exerted tremendous influences on human activities, havocking the human civilization, which is meaningful for human mitigation to natural hazards under the present global warming. At the same time, some uncertainties in reconstruction of paleo-environmental changes were discussed in the text.

  19. The interaction between deepwater channel systems and growing thrusts and folds, toe-thrust region of the deepwater Niger Delta

    Science.gov (United States)

    Jolly, Byami; Whittaker, Alex; Lonergan, Lidia

    2015-04-01

    Gravity-driven seaward-verging thrusts, landward-verging back-thrusts and associated folds often characterize the slope and deepwater settings of passive margins. These structures, found in the 'toe-thrust' region of the system, exert a significant control on sediment gravity flows because they create and determine the location and configuration of sediment depocentres and transport systems. Consequently, a quantitative understanding of the interaction between sediment gravity flows and seabed topography is required to understand these systems effectively. Here we make quantitative measurements of the geomorphic response of submarine channels to growing tectonic structures with the aim of providing new constraints on the long-term erosional dynamics of submarine channel systems. This study exploits 3D seismic data in the outer toe-thrust region of the deepwater Niger Delta to analyze the interaction between Plio-Pleistocene channel systems and actively growing folds and thrusts. We mapped folds and thrusts from the seismic data and we used this data to reconstruct the history of fold growth. We then used the sea-bed seismic horizon to build a 50 m resolution Digital Elevation Model (DEM) of the sea floor in Arc-GIS. We extracted channel long- profiles across growing structures from the DEM, and made measurements of channel geometries at regular intervals along the channel length. This information was used to infer morphodyanamic processes that sculpted the channel systems through time, and to estimate the bed shear stresses and fluid velocities of typical flow events. The bathymetric long profiles of these channels are relatively linear with concavity that range from -0.08 to -0.34, and an average gradient of ~1o. Actively growing thrusts are typically associated with a local steepening in channel gradient by a factor of up to 3, and this effect extends 0.5 - 2 km upstream of the thrust. Within these knickzones, channel incision increases by approximately by a

  20. Modeling of the anthropogenic heat flux and its effect on regional meteorology and air quality over the Yangtze River Delta region, China

    Science.gov (United States)

    Xie, Min; Liao, Jingbiao; Wang, Tijian; Zhu, Kuanguang; Zhuang, Bingliang; Han, Yong; Li, Mengmeng; Li, Shu

    2016-05-01

    Anthropogenic heat (AH) emissions from human activities caused by urbanization can affect the city environment. Based on the energy consumption and the gridded demographic data, the spatial distribution of AH emission over the Yangtze River Delta (YRD) region is estimated. Meanwhile, a new method for the AH parameterization is developed in the WRF/Chem model, which incorporates the gridded AH emission data with the seasonal and diurnal variations into the simulations. By running this upgraded WRF/Chem for 2 typical months in 2010, the impacts of AH on the meteorology and air quality over the YRD region are studied. The results show that the AH fluxes over the YRD have been growing in recent decades. In 2010, the annual-mean values of AH over Shanghai, Jiangsu and Zhejiang are 14.46, 2.61 and 1.63 W m-2, respectively, with the high value of 113.5 W m-2 occurring in the urban areas of Shanghai. These AH emissions can significantly change the urban heat island and urban-breeze circulations in the cities of the YRD region. In Shanghai, 2 m air temperature increases by 1.6 °C in January and 1.4 °C in July, the PBLH (planetary boundary layer height) rises up by 140 m in January and 160 m in July, and 10 m wind speed is enhanced by 0.7 m s-1 in January and 0.5 m s-1 in July, with a higher increment at night. The enhanced vertical movement can transport more moisture to higher levels, which causes the decrease in water vapor at ground level and the increase in the upper PBL (planetary boundary layer), and thereby induces the accumulative precipitation to increase by 15-30 % over the megacities in July. The adding of AH can impact the spatial and vertical distributions of the simulated pollutants as well. The concentrations of primary air pollutants decrease near the surface and increase at the upper levels, due mainly to the increases in PBLH, surface wind speed and upward air vertical movement. But surface O3 concentrations increase in the urban areas, with maximum

  1. Observation on the characteristics of sea-land breezes and its influence to air quality over Pearl River Delta region during dry season%珠三角干季海陆风特征及其对空气质量影响的观测

    Institute of Scientific and Technical Information of China (English)

    吴蒙; 罗云; 吴兑; 范绍佳

    2016-01-01

    Based on the sounding data obtained from the boundary layer observation experiment over Pearl River Delta (PRD) region during October 2004 and the corresponding hourly PM2.5 data, the characteristics of sea-land breezes and its influenceson quality over PRD region were discussed by Recirculation Factor (RF) and other methods. Recirculation factor was a useful tool to represent the atmospheric horizontal transmission capacity.With the influence of the cold air and warm air confront with each other during pollution days, the sea-land breezes occurred frequently as a result of the weak system wind, and air quality index had significant relation with the RF, the RF of 100~400m was about 0.5~0.8. The horizontal transmission capacity of vertical wind field was weak under the influence of sea-land breezes, not conducive to the spread of pollutants. As PRD controlled by cold air overall, the RF of vertical windreach up to 0.9, and sea-land breezes circulation was hard to developing,so the horizontal transmissions capacity was powerful and the pollutants could be spread effectually. Among the observations, the frequency of sea-land breezes was about 47.8%at the coastal station, and the 72.7%of sea-land breezes day was pollution day, the wind directionhad visible change in clockwise over time. The sea breeze occurred in 16:00, and reached the maximum in 20:00 with the influence height was about 600~800m. In the night, sea breeze may transport the pollutants back to inland, and gave rise to a peak value of PM2.5 concentration appeared at 19:00 to 21:00 in inland station.%通过2004年10月在珠江三角洲(以下简称“珠三角”)开展大气边界层观测试验得到的垂直风温资料和逐时PM2.5浓度资料,利用局地环流指数(RF)等方法研究了珠三角海陆风特征及其对空气质量的影响.结果表明:局地环流指数是表征局地大气输送能力的有效指标;冷暖气团对峙导致珠三角污染日背景风场较弱,沿海海

  2. Evaluation of the Factors that Control the Time-Dependent Inactivation Rate Coefficients of Bacteriophage MS2 and PRD1

    Science.gov (United States)

    Anders, R.; Chrysikopoulos, C. V.

    2004-12-01

    Batch experiments were conducted under both static and dynamic conditions to study the effects of temperature and the presence of sand on the inactivation process of viruses. The male--specific RNA coliphage, MS2, and the Salmonella typhimurium phage, PRD1, were used as model viruses for this study. Over 100 oven--baked borosilicate glass bottles with or without Monterey sand were filled with a low--ionic--strength phosphate buffered saline solution containing both bacteriophage and incubated at temperatures of 4o, 15o, or 25oC. The results of the batch experiments indicate that the inactivation process can be represented by a pseudo first-order expression with time--dependent rate coefficients. A combination of high temperature and the presence of sand appears to produce the greatest disruption to the surrounding protein coat of MS2. However, for PRD1, the lower activation energies derived from Arrhenius plots indicate a weaker dependence of the inactivation rate on temperature. Furthermore, the presence of an air--liquid--solid interface in the dynamic batch experiment containing sand produces the greatest damage to specific viral components of PRD1 that are required for infection. These results indicate the use of thermodynamic parameters based on the pseudo first--order inactivation expression allows better prediction of the inactivation of viruses in the environment.

  3. Análisis de patrones de vegetación a escala regional en el Bajo Delta Bonaerense del Río Paraná (Argentina)

    OpenAIRE

    Kandus,Patricia

    1997-01-01

    El objetivo general del presente trabajo fue describir e interpretar los patrones de distribución de especies y comunidades vegetales naturales en relación a los patrones de paisaje y el régimen de inundación en el Bajo Delta Bonaerense del Rio Paraná, desde un punto de vista regional. Se realizó una zonificación de unidades de paisaje en relación a los principales factores que determinan la heterogeneidad interna del área y su funcionamiento diferencial: patrones de paisaje y régimen hidroló...

  4. Detection of avian H7N9 influenza A viruses at the Yangtze Delta Region of China during early H7N9 outbreaks

    OpenAIRE

    Li, Yin; Huang, Xin-mei; Zhao, Dong-min; Liu, Yu-zhuo; He, Kong-wang; Liu, Yao-xing; Chen, Chang-hai; Long, Li-Ping; Xu, Yifei; Xie, Xing-xing; Han, Kai-kai; Liu, Xiao-yan; Yang, Jing; Zhang, You-Fa; Fan, Feng

    2016-01-01

    Since the first H7N9 human case in Shanghai, February 19, 2013, the emerging avian-origin H7N9 influenza A virus has become an epizootic virus in China, posing a potential pandemic threat to public health. From April 2 to April 28, 2013, 422 oral-pharyngeal and cloacal swabs were collected from birds and environmental surfaces at five live poultry markets (LPMs) and 13 backyard poultry farms (BPFs) across three cities, Wuxi, Suzhou, and Nanjing, in the Yangtze Delta Region. A total of 22 isol...

  5. Beam-helicity associated electroproduction of real photons ep {yields} e{gamma}{pi}N in the {Delta}-resonance region

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Giessen Univ. (Germany). 2. Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Akopov, N. [Yerevan Physics Institute (Argentina); Aschenauer, E.C. [DESY Zeuthen (Germany)] [and others; Collaboration: HERMES Collaboration

    2013-10-15

    The beam-helicity asymmetry in associated electroproduction of real photons, ep {yields} e{gamma}{pi}N, in the {Delta}(1232)-resonance region is measured using the longitudinally polarized HERA positron beam and an unpolarized hydrogen target. Azimuthal Fourier amplitudes of this asymmetry are extracted separately for two channels, ep {yields} e{gamma}{pi}{sup 0}p and ep {yields} e{gamma}{pi}{sup +}n, from a data set collected with a recoil detector. All asymmetry amplitudes are found to be consistent with zero.

  6. DELTAS: A new Global Delta Sustainability Initiative (Invited)

    Science.gov (United States)

    Foufoula-Georgiou, E.

    2013-12-01

    Deltas are economic and environmental hotspots, food baskets for many nations, home to a large part of the world population, and hosts of exceptional biodiversity and rich ecosystems. Deltas, being at the land-water interface, are international, regional, and local transport hubs, thus providing the basis for intense economic activities. Yet, deltas are deteriorating at an alarming rate as 'victims' of human actions (e.g. water and sediment reduction due to upstream basin development), climatic impacts (e.g. sea level rise and flooding from rivers and intense tropical storms), and local exploration (e.g. sand or aggregates, groundwater and hydrocarbon extraction). Although many efforts exist on individual deltas around the world, a comprehensive global delta sustainability initiative that promotes awareness, science integration, data and knowledge sharing, and development of decision support tools for an effective dialogue between scientists, managers and policy makers is lacking. Recently, the international scientific community proposed to establish the International Year of Deltas (IYD) to serve as the beginning of such a Global Delta Sustainability Initiative. The IYD was proposed as a year to: (1) increase awareness and attention to the value and vulnerability of deltas worldwide; (2) promote and enhance international and regional cooperation at the scientific, policy, and stakeholder level; and (3) serve as a launching pad for a 10-year committed effort to understand deltas as complex socio-ecological systems and ensure preparedness in protecting and restoring them in a rapidly changing environment. In this talk, the vision for such an international coordinated effort on delta sustainability will be presented as developed by a large number of international experts and recently funded through the Belmont Forum International Opportunities Fund. Participating countries include: U.S., France, Germany, U.K., India, Japan, Netherlands, Norway, Brazil, Bangladesh

  7. Feasibility of Rainwater Harvesting to fulfill potable water demand using quantitative water management in low-lying delta regions of Asia

    Science.gov (United States)

    Mahmood, A.; Hossain, F.

    2016-12-01

    Low-lying deltas of Asian region are usually densely populated and located in developing countries situated at the downstream end of major rivers. Extensive dam construction by the upstream countries has now caused water scarcity in large portions of low-lying deltas. Most inhabitants depend on shallow tube well for safe drinking water that tend to suffer from water quality issues (e.g. Arsenic contamination). In addition, people also get infected from water borne diseases like Cholera and Typhoid due to lack of safe drinking water. Developing a centralized piped network based water supply system is often not a feasible option in rural regions. Due to social acceptability, environment friendliness, lower capital and maintenance cost, rainwater harvesting can be the most sustainable option to supply safe drinking water in rural areas. In this study, first we estimate the monthly rainfall variability using long precipitation climatology from satellite precipitation data. The upper and lower bounds of monthly harvestable rainwater were estimated for each satellite precipitation grid. Taking this lower bound of monthly harvestable rainwater as input, we use quantitative water management concept to determine the percent of the time of the year potable water demand can be fulfilled. Analysis indicates that a 6 m³ reservoir tank can fulfill the potable water demand of a 6 person family throughout a year in almost all parts of this region.

  8. Variation in agricultural CO2 fluxes during the growing season, collected from more than ten eddy covariance towers in the Mississippi Delta Region

    Science.gov (United States)

    Runkle, B.; Suvocarev, K.; Reba, M. L.; Novick, K. A.; White, P.; Anapalli, S.; Locke, M. A.; Rigby, J.; Bhattacharjee, J.

    2016-12-01

    Agriculture is unique as an anthropogenic activity that plays both a large role in carbon and water cycling and whose management activities provide a key opportunity for responses to climate change. It is therefore especially crucial to bring field observations into the modeling community, test remote sensing products, encourage policy debate, and enable carbon offsets markets that generate revenue and fund climate-smart activities. The accurate measurement of agricultural CO2 exchange - both primary productivity and ecosystem respiration - in concert with evapotranspiration provides crucial information on agro-ecosystem functioning and improves our predictive capacity for estimating the impacts of climate change. In this study we report field measurements from more than 10 eddy covariance towers in the Lower Mississippi River Basin taken during the summer months of 2016. Many towers, some recently deployed, are being aggregated into a regional network known as Delta-Flux, which will ultimately include 15-20 towers by 2017. Set in and around the Mississippi Delta Region within Louisiana, Arkansas, and Mississippi, the network will collect flux, micrometeorological, and crop yield data in order to construct estimates of regional CO2 exchange. These time-series data are gap-filled using statistical and process-based models to generate estimates of summer CO2 flux. The tower network is comprised of sites representing widespread agriculture production, including rice, cotton, corn, soybean, and sugarcane; intensively managed pine forest; and bottomland hardwood forest. Unique experimental production practices are represented in the network and include restricted water use, bioenergy, and by-product utilization. Several towers compose multi-field sites testing innovative irrigation or management practices. Current mapping of agricultural carbon exchange - based on land cover layers and fixed crop emission factors - suggests an unconstrained carbon flux estimate in this

  9. Observational $\\Delta\

    CERN Document Server

    Hernández, Antonio García; Monteiro, Mário J P F G; Suárez, Juan Carlos; Reese, Daniel R; Pascual-Granado, Javier; Garrido, Rafael

    2015-01-01

    Delta Scuti ($\\delta$ Sct) stars are intermediate-mass pulsators, whose intrinsic oscillations have been studied for decades. However, modelling their pulsations remains a real theoretical challenge, thereby even hampering the precise determination of global stellar parameters. In this work, we used space photometry observations of eclipsing binaries with a $\\delta$ Sct component to obtain reliable physical parameters and oscillation frequencies. Using that information, we derived an observational scaling relation between the stellar mean density and a frequency pattern in the oscillation spectrum. This pattern is analogous to the solar-like large separation but in the low order regime. We also show that this relation is independent of the rotation rate. These findings open the possibility of accurately characterizing this type of pulsator and validate the frequency pattern as a new observable for $\\delta$ Sct stars.

  10. Assessment of the effectiveness of onsite exsitu remediation by enhanced natural attenuation in the Niger Delta region, Nigeria.

    Science.gov (United States)

    Okparanma, Reuben N; Azuazu, Ikeabiama; Ayotamuno, Josiah M

    2017-09-09

    This study was conducted to quantify and rank the effectiveness of onsite exsitu remediation by enhanced natural attenuation using soil quality index. The investigation was conducted at three oil spill sites in the Niger Delta (5.317°N, 6.467°E), Nigeria with a predominance of Oxisols. Baseline assessment and a two-step post-remediation monitoring of the sites were conducted. Target contaminants including total petroleum hydrocarbon (TPH) and BTEX (benzene, toluene, ethylbenzene, and xylene) were analyzed by gas chromatography-mass spectrometry. Results of the baseline assessment showed that TPH concentrations across the study sites averaged between 5113 and 7640 mg/kg at 0- to 1-m depth, which was higher than the local regulatory value of 5000 mg/kg. The soil quality index across the sites ranged between 68 and 45, suggesting medium to high potential ecological health risks with medium to high priority for remediation. BTEX concentrations followed a similar trend. However, after remediation TPH degraded rapidly initially and then slowly but asymptotically during the post-remediation monitoring period. Then, soil quality index across the study sites ranged between 100 and 58, indicating very low to medium potential ecological health risks. This demonstrates the effectiveness of onsite exsitu remediation by enhanced natural attenuation as a remediation strategy for petroleum-contaminated soils, which holds great promise for the Niger Delta province. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Emission characteristics of volatile organic compounds and their secondary organic aerosol formation potentials from a petroleum refinery in Pearl River Delta, China.

    Science.gov (United States)

    Zhang, Zhijuan; Wang, Hao; Chen, Dan; Li, Qinqin; Thai, Phong; Gong, Daocheng; Li, Yang; Zhang, Chunlin; Gu, Yinggang; Zhou, Lei; Morawska, Lidia; Wang, Boguang

    2017-02-08

    A campaign was carried out to measure the emission characteristics of volatile organic compounds (VOCs) in different areas of a petroleum refinery in the Pearl River Delta (PRD) region in China. In the refining area, 2-methylpentane, 2,3-dimethylbutane, methylcyclopentane, 3-methylhexane, and butane accounted for >50% of the total VOCs; in the chemical industry area, 2-methylpentane, p-diethylbenzene, 2,3-dimethylbutane, m-diethylbenzene and 1,2,4-trimethylbenzene were the top five VOCs detected; and in the wastewater treatment area, the five most abundant species were 2-methylpentane, 2,3-dimethylbutane, methylcyclopentane, 3-methylpentane and p-diethylbenzene. The secondary organic aerosol (SOA) formation potential was estimated using the fractional aerosol coefficients (FAC), secondary organic aerosol potential (SOAP), and SOA yield methods. The FAC method suggests that toluene, p-diethylbenzene, and p-diethylbenzene are the largest contributors to the SOA formation in the refining, chemical industry, and wastewater treatment areas, respectively. With the SOAP method, it is estimated that toluene is the largest contributor to the SOA formation in the refining area, but o-ethyltoluene contributes the most both in the chemical industry and wastewater treatment areas. For the SOA yield method, aromatics dominate the yields and account for nearly 100% of the total in the three areas. The SOA concentrations estimated of the refining, chemical industry and wastewater treatment areas are 30, 3835 and 137μgm(-3), respectively. Despite the uncertainties and limitations associated with the three methods, the SOA yield method is suggested to be used for the estimation of SOA formation from the petroleum refinery. The results of this study have demonstrated that the control of VOCs, especially aromatics such as toluene, ethyltoluene, benzene and diethylbenzene, should be a focus of future regulatory measures in order to reduce PM pollution in the PRD region.

  12. Gravity-based model for regional flexure induced by crustal loading by the 14-km-thick Mississippi delta

    Science.gov (United States)

    Ajala, R. A.; Mann, P.

    2016-12-01

    We used gravity data constrained by deep-penetration seismic reflection lines to determine the crustal structure beneath the Mississippi delta, the seventh-largest deltaic accumulation on Earth. The observed gravity anomaly at the margin consist of a high of 50 mGal over the shelf with a low of -27 mGal at a landward distance of 250 km, a low of -18 mGal at a seaward distance of 136 km, and another high of 23 mGal at a seaward distance of 178 km from the shelf edge. The gravity high is centered over the thickest part of the delta, much of which has been deposited since the Miocene. The elastic thickness of the underlying crust is estimated by comparing the amplitude and wavelength of the observed gravity anomaly to the predicted anomaly based on simple elastic plate models. The process-oriented gravity modeling approach has been used to flexurally backstrip the sediments and add the present-day water depth to obtain the total tectonic subsidence (TTS). The gravity effect due to the initial rift structure obtained from the TTS known as the "rifting anomaly" and sediment loading called the "sedimentation anomaly" are used to compute the present-day gravity anomaly. The best fit result is for a margin which sediments were deposited on thinned transitional crust with an elastic thickness of 48 km. Results from flexural modeling show that top of basement has been flexed up to 8 km over a lateral distance of more than 500 km by the deltaic load. The map-view shape of the uplifted rim with a predicted, maximum topographic expression of 40 m is egg-shaped with its northern, more narrow tip crossing the Mississippi Valley near Memphis, its northwestern part running parallel to the northern Ouachita Mountains, its western part tracking parallel to the Mexia-Balcones fault system of Texas, and its eastern edge parallel to the west coast of Florida. While the overall magnitude of the topographic flexure is low, delta-related flexure may have contributed to the Miocene

  13. Mercury methylation, export and bioaccumulation in rice agriculture - model results from comparative and experimental studies in 3 regions of the California Delta, USA

    Science.gov (United States)

    Windham-Myers, L.; Fleck, J.; Eagles-Smith, C.; Ackerman, J.

    2013-12-01

    Seasonally flooded wetland ecosystems are often poised for mercury (Hg) methylation, thus becoming sources of methylmercury (MeHg) to in situ and downstream biota. The seasonal flooding associated with cultivation of rice (Oryza sativa) also generates MeHg, which may be stored in sediment or plants, bioaccumulated into fauna, degraded or exported, depending on hydrologic and seasonal conditions. While many U.S. waters are regulated for total Hg concentrations based on fish targets, California's Sacramento-San Joaquin Delta (Delta) will soon implement the first MeHg total maximum daily load (TMDL) control program. Since 2007, a conceptual model (DRERIP-MCM) and several ecosystem-level studies have been advanced to better understand the mechanisms behind Hg methylation, export and bioaccumulation within Delta wetlands, including rice agriculture. Three Delta rice-growing regions (Yolo Bypass, Cosumnes River, Central Delta) of varied soil characteristics, mining influences and hydrology, were monitored over full crop years to evaluate annual MeHg dynamics. In addition to fish tissue Hg accumulation, a broad suite of biogeochemical and hydrologic indices were assessed and compared between wetland types, seasons, and regions. In general, Delta rice fields were found to export MeHg during the post-harvest winter season, and promote MeHg uptake in fish and rice grain during the summer growing season. As described in a companion presentation (Eagles-Smith et al., this session), the experimental Cosumnes River study suggests that rice-derived dissolved organic carbon (DOC) fuels MeHg production and uptake into aquatic foodwebs. Explicit DRERIP-MCM linkages for the role of rice-DOC in MeHg production, export and bioaccumulation were verified across two summers (2011, 2012): rice biomass and root productivity influenced porewater DOC availability and microbial processes, which drove sediment MeHg production and flux to surface water, promoting MeHg bioaccumulation in fish

  14. The Relationship between Urban Sprawl and Farmland Displacement in the Pearl River Delta, China

    Directory of Open Access Journals (Sweden)

    Shiqiang Du

    2013-12-01

    Full Text Available China is rapidly urbanizing and will inevitably face trade-offs between promoting economic growth through further urbanization and protecting fertile farmland against accelerated urban expansion. This paper presents how this dilemma is being addressed in one of the most rapidly urbanizing regions in China, the Pearl River Delta (PRD, by means of assessing urban growth and farmland dynamic, as well as their complex relationships. Land use maps derived from Landsat imagery for 1990, 2000 and 2010 show a process of accelerated urban sprawl whereby built-up lands have more than quadrupled and scattered centers have merged into megacities. Nonetheless, the land use efficiency is considerably low and is declining relative to Hong Kong and Macau with respect to urban population density. On the other hand, the spreading of urban areas on farmlands causes new farmland reclamation and accelerated deforestation in the hilly surroundings. In addition, the displaced farmlands do not ensure food production because of both reclaiming farmlands on infertile lands and diversifying farming activities from grain production to market-oriented ones. The accelerated urbanization and farmland displacement are driven by profit-oriented development strategy and ineffective land use planning. Our findings demonstrate how spatial analysis can help to investigate the integrated effects of land policies on landscape.

  15. Hair mercury levels and food consumption in residents from the Pearl River Delta: South China.

    Science.gov (United States)

    Shao, Dingding; Kang, Yuan; Cheng, Zhang; Wang, Hongsheng; Huang, Minjuan; Wu, Shengchun; Chen, Kunci; Wong, Ming H

    2013-01-15

    The Pearl River Delta (PRD) is located in the Southern part of China and is the main region for fish culture in Guangdong Province. In order to assess the potential health risks associated with dietary consumption of mercury, hair samples from 91 urban, town and fishing village residents, 37 species of fish, cereal, vegetables, and meat samples were collected. The average total mercury (THg) and methylmercury (MeHg) concentrations in hair were 1.08 ± 0.94 and 0.58 ± 0.59 μg/g, respectively. Daily Hg intake via fish consumption is significantly correlated with THg and MeHg accumulated in human hair (r=0.48, p<0.01; r=0.43, p<0.01). The estimated daily intake of Hg via different food types showed that both fish and cereal consumption were the two main routes of Hg exposure for residents in the sampling areas. Besides food intake, smoking was also an important source for daily THg intake in the smoke group, contributing 11-18% to EDI of THg.

  16. Spatio-temporal characteristics of the extreme precipitation by L-moment-based index-flood method in the Yangtze River Delta region, China

    Science.gov (United States)

    Yin, Yixing; Chen, Haishan; Xu, Chong-Yu; Xu, Wucheng; Chen, Changchun; Sun, Shanlei

    2016-05-01

    The regionalization methods, which "trade space for time" by pooling information from different locations in the frequency analysis, are efficient tools to enhance the reliability of extreme quantile estimates. This paper aims at improving the understanding of the regional frequency of extreme precipitation by using regionalization methods, and providing scientific background and practical assistance in formulating the regional development strategies for water resources management in one of the most developed and flood-prone regions in China, the Yangtze River Delta (YRD) region. To achieve the main goals, L-moment-based index-flood (LMIF) method, one of the most popular regionalization methods, is used in the regional frequency analysis of extreme precipitation with special attention paid to inter-site dependence and its influence on the accuracy of quantile estimates, which has not been considered by most of the studies using LMIF method. Extensive data screening of stationarity, serial dependence, and inter-site dependence was carried out first. The entire YRD region was then categorized into four homogeneous regions through cluster analysis and homogenous analysis. Based on goodness-of-fit statistic and L-moment ratio diagrams, generalized extreme-value (GEV) and generalized normal (GNO) distributions were identified as the best fitted distributions for most of the sub-regions, and estimated quantiles for each region were obtained. Monte Carlo simulation was used to evaluate the accuracy of the quantile estimates taking inter-site dependence into consideration. The results showed that the root-mean-square errors (RMSEs) were bigger and the 90 % error bounds were wider with inter-site dependence than those without inter-site dependence for both the regional growth curve and quantile curve. The spatial patterns of extreme precipitation with a return period of 100 years were finally obtained which indicated that there are two regions with highest precipitation

  17. Distribution, sources, and fluxes of heavy metals in the Pearl River Delta, South China.

    Science.gov (United States)

    Geng, Junjie; Wang, Yiping; Luo, Hanjin

    2015-12-30

    Riverine samples were collected at various locations in the Pearl River Delta (PRD) to determine the concentrations of heavy metals (Cr, Ni, Cu, Mn, Zn, Cd, and Pb) in time and space and to estimate the fluxes of heavy metals to the coastal waters off South China. Most of the elements exhibit clear temporal and spatial trends. Principal component analysis shows that surface erosion is the major factor affecting metal concentrations in particulates in the PRD. Natural geology is an important source of these heavy metals. The annual fluxes of Cr, Ni, Cu, Mn, Zn, Cd, and Pb in upstream and downstream were 445, 256, 241, 3293, 1279, 12, and 317 t/year and 1823, 1144, 1786, 15,634, 6183, 74, and 2017 t/year, respectively. A comparison indicated that the annual fluxes of Mn accounted for 1.3% of the global river fluxes, whereas other elements contribute <1%.

  18. Challenges and opportunities in the design and construction of a GIS-based emission inventory infrastructure for the Niger Delta region of Nigeria.

    Science.gov (United States)

    Fagbeja, Mofoluso A; Hill, Jennifer L; Chatterton, Tim J; Longhurst, James W S; Akpokodje, Joseph E; Agbaje, Ganiy I; Halilu, Shaba A

    2017-01-27

    Environmental monitoring in middle- and low-income countries is hampered by many factors which include enactment and enforcement of legislations; deficiencies in environmental data reporting and documentation; inconsistent, incomplete and unverifiable data; a lack of access to data; and technical expertise. This paper describes the processes undertaken and the major challenges encountered in the construction of the first Niger Delta Emission Inventory (NDEI) for criteria air pollutants and CO2 released from the anthropogenic activities in the region. This study focused on using publicly available government and research data. The NDEI has been designed to provide a Geographic Information System-based component of an air quality and carbon management framework. The NDEI infrastructure was designed and constructed at 1-, 10- and 20-km grid resolutions for point, line and area sources using industry standard processes and emission factors derived from activities similar to those in the Niger Delta. Due to inadequate, incomplete, potentially inaccurate and unavailable data, the infrastructure was populated with data based on a series of best possible assumptions for key emission sources. This produces outputs with variable levels of certainty, which also highlights the critical challenges in the estimation of emissions from a developing country. However, the infrastructure is functional and has the ability to produce spatially resolved emission estimates.

  19. Spatio-temporal analysis of the extreme precipitation by the L-moment-based index-flood method in the Yangtze River Delta region, China

    Science.gov (United States)

    Yin, Yixing; Chen, Haishan; Xu, Chongyu; Xu, Wucheng; Chen, Changchun

    2014-05-01

    The regionalization methods which 'trade space for time' by including several at-site data records in the frequency analysis are an efficient tool to improve the reliability of extreme quantile estimates. With the main aims of improving the understanding of the regional frequency of extreme precipitation and providing scientific and practical background and assistance in formulating the regional development strategies for water resources management in one of the most developed and flood-prone regions in China, the Yangtze River Delta (YRD) region, in this paper, L-moment-based index-flood (LMIF) method, one of the popular regionalization methods, is used in the regional frequency analysis of extreme precipitation; attention was paid to inter-site dependence and its influence on the accuracy of quantile estimates, which hasn't been considered for most of the studies using LMIF method. Extensive data screening of stationarity, serial dependence and inter-site dependence was carried out first. The entire YRD region was then categorized into four homogeneous regions through cluster analysis and homogenous analysis. Based on goodness-of-fit statistic and L-moment ratio diagrams, Generalized extreme-value (GEV) and Generalized Normal (GNO) distributions were identified as the best-fit distributions for most of the sub regions. Estimated quantiles for each region were further obtained. Monte-Carlo simulation was used to evaluate the accuracy of the quantile estimates taking inter-site dependence into consideration. The results showed that the root mean square errors (RMSEs) were bigger and the 90% error bounds were wider with inter-site dependence than those with no inter-site dependence for both the regional growth curve and quantile curve. The spatial patterns of extreme precipitation with return period of 100 years were obtained which indicated that there are two regions with the highest precipitation extremes (southeastern coastal area of Zhejiang Province and the

  20. A Combination of Different Synthetic Aperture Radar (SAR) Techniques for Bottom-Fast Ice and Permafrost Monitoring in Canadian Polar Region (Mackenzie Delta)

    Science.gov (United States)

    Alasset, P.; Parsons, G.; Yue, B.; Chamberland, J.; Mulvie, J.

    2009-12-01

    The Mackenzie Delta is a unique region in the Canadian North which is rich in hydrocarbons and supports a fragile ecosystem. A need exists to define nominal remote coastal conditions prior to hydrocarbon extraction and to assist in monitoring conditions once the extraction will be underway. Near shore the formation of Bottom-Fast Ice (BFI) plays an important role in the region’s seasonal environmental changes and in the understanding of arctic coastal environmental and geophysical control processes. BFI is ice that has frozen to the seabed in shallow sea water and forms in areas where the sea water is shallow. These regions control permafrost distribution, spring overflow and potential strudel scours - holes in the frozen seafloor from flowing fresh water in rivers and streams during spring in the Beaufort Sea - and influence channel mouth constraints and early breakup season flood routing. BFI has been studied by generating D-InSAR (Differential SAR Interferometry) coherence maps during the winter of 2007-2008 and 2008-2009 using a combination of SAR image pairs from the TerraSAR-X space borne sensor. The results derived from these data were compared to results obtained from ALOS-PALSAR and RADARSAT-2 using advanced polarimetric techniques for BFI delineation. All coherence maps of the winter 2008-2009 data were assembled and compiled to demonstrate seasonal changes throughout the winter. The results of these analyses indicate that deriving coherence maps from repeat-pass data generates a product that is indicative of BFI regions; though relying on an entirely different land characteristic than polarimetric BFI delineation (e.g. ground stability vs. dielectric constants). Through the use of various polarimetric channels, a good discrimination between BFI regions and ice-covered land regions has been noted in the past. With specialised analysts, it is possible to reasonably outline BFI regions from these polarimetric datasets. Additional to these standard

  1. Hydrochemistry of surface water and groundwater in the shale bedrock, Cross River Basin and Niger Delta Region, Nigeria

    Science.gov (United States)

    Nganje, T. N.; Hursthouse, A. S.; Edet, Aniekan; Stirling, D.; Adamu, C. I.

    2017-05-01

    Water chemistry in the shale bedrock of the Cretaceous-Tertiary of the Cross River and Niger Delta hydrological basins has been investigated using major ions. To carry out a characterization of the water bearing units, 30 and 16 representatives surface and groundwater samples were collected. The evolution of the water is characterized by enhanced content of sodium, calcium and sulphate as a result of leaching of shale rock. The spatial changes in groundwater quality of the area shows an anomalous concentrations of ions in the central parts, while lower values characterize the eastern part of the basin covering Ogoja, Ikom and Odukpani areas. The values of total dissolved solids (TDS) and ions increases down gradient in the direction of groundwater flow. The dissolution of halite and gypsum explains part of the contained Na+, Ca2+, Cl- and SO4 2-, but other processes such as ion exchange, silicate weathering and pyrite oxidation also contribute to water composition. The assessment with contamination indicators such as TDS, hardness, chloride, nitrate and sulphate indicates that the water in area is suitable for human consumption in some locations. Modelling using MINTEQA2 program shows that the water from all the shale water bearing units are under saturated with respect to gypsum.

  2. Regional ecological risk assessment of in the Liaohe River Delta wetlands%辽河三角洲湿地区域生态风险评价

    Institute of Scientific and Technical Information of China (English)

    付在毅; 许学工; 林辉平; 王宪礼

    2001-01-01

    Ecological risk assessment is a new study field. Its objective is to estimate the possibility and magnitude in which some undesired ecological events will occur by using mathematics, probability and other risk analysis techniques. Regional ecological risk assessment is one branch of ecological risk assessment,for which both the receptors and sources of risk must be in regional scale, and the exposure and effects assessment must account their uncertainty and spatial heterogeneity. In the case study of the Liaohe River Delta wetlands.this article inguires into the theory and method of regional ecological risk assessment.   First, we select birds and their habitats as risk receptors after analyzed the landscape framework and ecological function of the wetlands.   Second, we define the mainly risk sources in this region including flood, drought, storm tide and oil pollution events. According to the statistic of the region, the probability and distributing of each kind of risk sources are gained.   Third, the habitat receptor is exposed under risk sources and contacts with bird receptor. Risk sources will affect the habitat elements and the birds will be harmed. In the exposure and hazard analysis, we use ecological index to denote the important degree of each habitat, use fragile index to show their features of anti-risk. Hazard consequences are analyzed, which formed by different risk sources. In order to compare the risk brought by different risk source, we use AHP method to get the weigh of each kind of risk sources.   Finally, risk assessment is the integrated phase of the research. Because of the spatial heterogeneity of risk sources, all risk sources are overlaid in the region, which divides the region into 122 risk areas. Within each risk area there is homogeneous for risk sources but heterogeneous for habitats. So we can get the ecological index and fragile index of each risk area according to the types of habitats in it, then combine

  3. PM2.5 acidity at a background site in the Pearl River Delta region in fall-winter of 2007-2012.

    Science.gov (United States)

    Fu, Xiaoxin; Guo, Hai; Wang, Xinming; Ding, Xiang; He, Quanfu; Liu, Tengyu; Zhang, Zhou

    2015-04-09

    Based on field observations and thermodynamic model simulation, the annual trend of PM2.5 acidity and its characteristics on non-hazy and hazy days in fall-winter of 2007-2012 in the Pearl River Delta region were investigated. Total acidity ([H(+)](total)) and in-situ acidity ([H(+)](in-situ)) of PM2.5 significantly decreased (F-test, p 0.6), NH4NO3 was most likely formed via homogenous reaction. When the acidity was high (R ≤ 0.6), the gas-phase formation of NH4NO3 was inhibited, and the proportion of NO3(-) produced via heterogeneous reaction of N2O5 became significant.

  4. 长三角地区冬季供暖模式选择研究%Heating Mode Selection of Yangtze River Delta Region in Winter

    Institute of Scientific and Technical Information of China (English)

    孙仲武

    2012-01-01

    通过对国内现有供暖方式的优缺点对照分析,提出长三角地区供暖方案选择的原则.水源、地热源、空气源与太阳能相结合的多元化供暖模式将会是发展方向,供暖末端系统宜选用低温热水地板辐射或热风采暖系统.%Baaed on analyzing the advantages and disadvantages of existing domestic heating mode, the paper proposed the selection principle of healing mode in Yangtze River Delta region. The heating mode of combining with the water, geothermal heating, air source and solar will be the development direction of heating system. The end of heating system can use low temperature hot water floor radiation or hot air heating system.

  5. Delta robot

    NARCIS (Netherlands)

    Herder, J.L.; Van der Wijk, V.

    2010-01-01

    The invention relates to a delta robot comprising a stationary base (2) and a movable platform (3) that is connected to the base with three chains of links (4,5,6), and comprising a balancing system incorporating at least one pantograph (7) for balancing the robot's center of mass, wherein the at le

  6. Delta robot

    NARCIS (Netherlands)

    Herder, J.L.; Van der Wijk, V.

    2010-01-01

    The invention relates to a delta robot comprising a stationary base (2) and a movable platform (3) that is connected to the base with three chains of links (4,5,6), and comprising a balancing system incorporating at least one pantograph (7) for balancing the robot's center of mass, wherein the at le

  7. SCP-Based Yangtze River Delta Region under the Framework of SWOT Analysis of the Development of 4PL%基于SCP框架下长三角地区发展第四方物流的SWOT分析

    Institute of Scientific and Technical Information of China (English)

    金石

    2012-01-01

    从第四方物流的概念入手,对长三角的物流现状进行分析,旨在找到长三角地区发展第四方物流的方向与方法。随着跨国企业在长三角纷纷落户,长三角与国际经济的合作越发紧密,从某种程度上说,长三角区域内的制造业和服务业等代表了国际发展的趋势和要求,而物流行业又同区域制造业和服务业的发展息息相关,因此,长三角物流行业与国际接轨具有紧迫性。从提高区域经济发展效率看,长三角必须要将第四方物流作为重点领域加以考虑。%From the concept of fourth party logistics,analysis the current situation of logistics of the Yangtze River Delta,to find the fourth party logistics development direction and method of the Yangtze River Delta.Along with the multinational company have settled in the Yangtze River Delta,the Yangtze River Delta and international economic cooperates more closely,to some extent,the manufacturing industry and service industry and so on of the Yangtze River Delta region behalf of the international development trend and requirements,and the logistics industry with regional manufacturing industry and service industry development,therefore,with the urgency of the Yangtze River Delta logistics industry and international to conform.From enhancing regional economic development efficiency,Yangtze River Delta must be considered as key areas of the 4PL.

  8. Submicron aerosol analysis and organic source apportionment in an urban atmosphere in Pearl River Delta of China using high-resolution aerosol mass spectrometry

    Science.gov (United States)

    He, Ling-Yan; Huang, Xiao-Feng; Xue, Lian; Hu, Min; Lin, Yun; Zheng, Jun; Zhang, Renyi; Zhang, Yuan-Hang

    2011-06-01

    The Pearl River Delta (PRD) region in South China is one of the most economically developed regions in China while also noted for its severe air pollution, especially in the urban environments. In order to understand in depth the aerosol chemistry and the emission sources in PRD, an Aerodyne high-resolution time-of-flight aerosol mass spectrometer (HR-ToF-AMS) was deployed at an urban site in the Hong Kong-Shenzhen metropolitan area between 25 October and 2 December 2009. Ten minute-resolved measurement data were analyzed, and an average mass concentration of 44.5 ± 34.0 μg m-3 was calculated for the entire campaign. On average, organic matter was the most abundant PM1 component accounting for 39.7% of the total mass, followed by sulfate (24.5%), black carbon (measured by aethalometer, 14.0%), ammonium (10.2%), nitrate (10.0%), and chloride (1.6%). Moreover, organic matter comprised an increasing fraction of the PM1 loading as the PM1 loading increased, denoting its key role in particulate pollution in this region. Calculations of organic elemental composition based on the high-resolution organic mass spectra obtained indicated that C, H, O, and N on average contributed 33.8%, 55.1%, 10.2%, and 0.9%, respectively, to the total atomic numbers of organic aerosol (OA), which corresponded to an OM/OC ratio (the ratio of organic matter mass/organic carbon mass) of 1.57 ± 0.08. Positive matrix factorization analysis was then conducted on the high-resolution organic mass spectral data set. Four OA components were identified, including a hydrocarbon-like (HOA), a biomass burning (BBOA), and two oxygenated (LV-OOA and SV-OOA) components, which on average accounted for 29.5%, 24.1%, 18.8%, and 27.6%, respectively, of the total organic mass. The HOA was found to have contributions from both fossil fuel combustion and cooking emissions, while the BBOA was well correlated with acetonitrile, a known biomass burning marker. The LV-OOA and SV-OOA corresponded to more aged and

  9. Contribution of the aquitard to the regional groundwater hydrochemistry of the underlying confined aquifer in the Pearl River Delta, China.

    Science.gov (United States)

    Wang, Ya; Jiao, Jiu Jimmy; Cherry, John A; Lee, Chun Ming

    2013-09-01

    Aquitards are capable of generating and preserving large amounts of chemicals. The release of the chemicals from the aquitards poses a potential contamination risk to groundwater that may be used as a drinking water source. This work aimed to identify the contribution of hydrogeochemical processes in the aquitards to groundwater hydrochemistry in the underlying confined basal aquifer by studying the coastal Quaternary aquifer-aquitard system of the Pearl River Delta, China. The system was submerged by paleo-seawater in the early Holocene and mainly receives infiltration of precipitation at present, as indicated by investigations on stable isotopes (δ(2)H, δ(18)O), water chemistry (SO4(2-) and Cl(-)) and salinity. Significant correlations between total dissolved solids in the basal aquifer and the thickness of the overlying aquitard further suggested the contribution of the aquitard to the groundwater hydrochemistry in the aquifer. Significant correlations between the chloride concentrations in aquitard porewater and that in groundwater in the aquifer, and between the thickness of the aquitard and the chloride concentrations in groundwater indicated the strong influence of the aquitard on the chloride in the aquifer. This is probably because the low-permeability aquitard is capable of preserving the paleo-seawater in the aquifer and releasing the salinity from the aquitard down to the aquifer via downward flow or diffusion. Isotopic and geochemical studies revealed that the aquitard is also responsible for generating and preserving large amounts of naturally occurring ammonium. Analysis between the concentrations of ammonium in groundwater in the basal aquifer and the total available ammonium in aquitard sediments suggested that the former is significantly controlled by the latter.

  10. Application of discrete choice experiment to assess farmers' willingness to report swine diseases in the Red River Delta region, Vietnam.

    Science.gov (United States)

    Pham, Hoa T T; Peyre, Marisa; Trinh, Tuyen Quang; Nguyen, Oanh Cong; Vu, Ton Dinh; Rukkwamsuk, Theera; Antoine-Moussiaux, Nicolas

    2017-03-01

    A discrete choice experiment (DCE) is carried out to value socio-economic factors influencing the farmer's decision to report swine diseases and to assess the willingness of farmers to report swine diseases. Data were collected between March and July 2015 in two provinces in the Red River Delta, Northern Vietnam, from 196 pig producers by face-to face interview. A conditional logit model is used to measure the relative importance of the socio-economic factors and calculate the expected probability of disease reporting under changes of levels of these factors. Results of the study indicated that the likelihood of compensation and the type of culling implemented (all or only unrecovered pigs) are the two most important factors influencing farmer reporting. Compensation level, movement restriction and delay in compensation payment also have significant impacts on farmer's decision to report animal disease but they are not as important as the above factors. Three different scenarios including changes in six different factors (attributes) are tested to predict probability of animal disease reporting. Under the current situation (uncertainty of being compensated), only 4% of the farmers would report swine disease outbreak to the official surveillance system if the culling policy involves all pigs in affected farms. This number is increased to 26% if culling in affected farms is restricted to unrecovered pigs only. Ensuring certainty of compensation increases reporting probability by up to 50% and 90% if all or only unrecovered pigs are destroyed, respectively. The results of this study are important for improving the performance and sustainability of swine disease surveillance system in Vietnam. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. STUDY ON THE FREQUENCY AND PRINCIPLE OF FLOOD CATASTROPHE IN THE CHANGJIANG DELTA AND ITS NEIGHBORING REGIONS IN THE LAST 2000 YEARS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Documented materials, especially those about flooding catastrophe, are abundant comprehensive and well-preserved, which makes possible the systematical collection of materials about historical document about climate evolu tion in Changjiang (Yangtze) Delta region and its neighboring areas. We make good use of the exceptional information to discuss the genesis and principle of flooding in this region. Analysis shows that the main flooding periods in the studied region in the last 2000 years were the Western Jin Dynasty, Eastern Jin Dynasty, Northern and Southern Dynasties, South ern Song Dynasty, Yuan Dynasty, Ming Dynasty and Qing Dynasty. The periods with flooding peak values were the 4th century, 5th century, 7th century, 9th century, early 12th century, early 14th century, mid-15th century, and early 18th century A. D. Possibility of reappearance of flooding peak value in the early 21st century will be great, and the haz ard prevention and the hazard reduction will be still hard.

  12. Lack of association of delta-aminolevulinate dehydratase polymorphisms with blood lead levels and hemoglobin in Romanian women from a lead-contaminated region.

    Science.gov (United States)

    Rabstein, Sylvia; Unfried, Klaus; Ranft, Ulrich; Illig, Thomas; Kolz, Melanie; Mambetova, Chinara; Vlad, Mariana; Roman, Cecilia; Weiss, Tobias; Becker, Doreen; Brüning, Thomas; Pesch, Beate

    2008-01-01

    As part of a project on environmental pollution, this study aimed to evaluate associations between blood lead (BPb) levels, hemoglobin (Hb) content, and single-nucleotide polymorphisms (SNPs) of delta-aminolevulinic acid dehydratase (ALAD) gene in 129 unrelated women from Romania. Five SNPs (rs1805313, rs2228083, rs1805312, rs1800435, rs1139488) were analyzed with respect to haplotype structure and impact on BPb levels and Hb content with proportional odds and analysis of covariance models. Combinations of SNPs were rare (16%). Low haplotype diversity was found with seven haplotypes. One rare haplotype implied the C allele of rs1800435, often referred to as the ALAD2 allele (frequency 8.6%). The putative risk genotype (CC) occurred in only one woman with BPb below 0.5 microg/dl. Median BPb was 4.8 microg/dl and differed markedly by community with a level of 12.5 microg/dl near a mining-spill region. Hb was regular (interquartile range 12.3-13.7 g/dl) and not correlated with BPb, although quantitatively lower in women living near the spill region. No significant associations were found for BPb or Hb with SNPs, haplotypes, or diplotypes. BPb levels were higher in this region than in populations from industrialized countries but without hematotoxic effects. An impact of ALAD2 on BPb or Hb was not seen in these women.

  13. Contribution of the aquitard to the regional groundwater hydrochemistry of the underlying confined aquifer in the Pearl River Delta, China

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Ya [Department of Earth Sciences, The University of Hong Kong, Hong Kong (China); Jiao, Jiu Jimmy, E-mail: jjiao@hku.hk [Department of Earth Sciences, The University of Hong Kong, Hong Kong (China); Cherry, John A. [School of Engineering, University of Guelph, Guelph, ON N1G 2W1 (Canada); Lee, Chun Ming [Department of Earth Sciences, The University of Hong Kong, Hong Kong (China)

    2013-09-01

    Aquitards are capable of generating and preserving large amounts of chemicals. The release of the chemicals from the aquitards poses a potential contamination risk to groundwater that may be used as a drinking water source. This work aimed to identify the contribution of hydrogeochemical processes in the aquitards to groundwater hydrochemistry in the underlying confined basal aquifer by studying the coastal Quaternary aquifer–aquitard system of the Pearl River Delta, China. The system was submerged by paleo-seawater in the early Holocene and mainly receives infiltration of precipitation at present, as indicated by investigations on stable isotopes (δ{sup 2}H, δ{sup 18}O), water chemistry (SO{sub 4}{sup 2−} and Cl{sup −}) and salinity. Significant correlations between total dissolved solids in the basal aquifer and the thickness of the overlying aquitard further suggested the contribution of the aquitard to the groundwater hydrochemistry in the aquifer. Significant correlations between the chloride concentrations in aquitard porewater and that in groundwater in the aquifer, and between the thickness of the aquitard and the chloride concentrations in groundwater indicated the strong influence of the aquitard on the chloride in the aquifer. This is probably because the low-permeability aquitard is capable of preserving the paleo-seawater in the aquifer and releasing the salinity from the aquitard down to the aquifer via downward flow or diffusion. Isotopic and geochemical studies revealed that the aquitard is also responsible for generating and preserving large amounts of naturally occurring ammonium. Analysis between the concentrations of ammonium in groundwater in the basal aquifer and the total available ammonium in aquitard sediments suggested that the former is significantly controlled by the latter. - Highlights: • Aquitard porewater components are similar to that of groundwater in the aquifer. • Influence of the aquitard on Cl{sup

  14. Regional Ecological Risk Assessment of Wetland in the Huanghe River Delta%黄河三角洲湿地区域生态风险评价

    Institute of Scientific and Technical Information of China (English)

    许学工; 林辉平; 付在毅; 布仁仓

    2001-01-01

    以黄河三角洲为例进行了区域生态风险评价理论和方法的探讨。针对黄河三角洲主要生态风险源洪涝、干旱、风暴潮灾害、油田污染事故以及黄河断流的概率进行了分级评价;并提出度量生态损失与生态风险的指标和公式,分析了风险源的危害作用;运用遥感资料、历史记录、调查数据和地理信息系统(GIS)技术,完成了区域生态风险综合评价;在此基础上提出黄河三角洲的区域生态风险管理对策。%Through the case study of the wetland in the Huanghe River (Yellow River) delta,the concept of regional ecological risk assessment is inquired into,and a set of assessment method was developed.The main process of regional ecological risk assessment includes 5 stages:regional analysis,risk receptor selection,risk sources analysis,exposure and hazard analysis,and integrated risk assessment.Arming at flood,drought,storm tide,petroleum pollution accident and flow breaking in the lower Huanghe River,the probability and distribution of each kind of risk sources are evaluated.The authors bring forward indexes and formulas to measure hazarded degree and risk value of ecosystem.By using remote sensing data,historic record,survey data and by means of geographical information system (GIS),regional ecological risk assessment is finished.On the basis of assessment result,the environmental risk management countermeasure of the Huanghe River delta is advanced.

  15. 珠江三角洲3000t内河集装箱船最佳航线探讨%Optimal Route of 3000 DWT Inland Container Ship in Pearl River Delta

    Institute of Scientific and Technical Information of China (English)

    王艳; 董国祥

    2011-01-01

    Pearl River Delta(PRD) is an important base of manufacturing industry in the world. With the development of the economy in PRD, the container volume of inland transport through PRD has increased greatly. After investigating inland ports, waterways and ship types in PRD,the optimal route of 3000 DWT container ship from Nan-sha to Sanshui is put forward to prepare for developing new ship types for the development of PRD container transport.%珠江三角洲是我国与世界重要的制造业基地,随着珠江三角洲经济的发展,近年来通过珠江三角洲内河运输的集装箱量有了很大的增长.在实地调研珠江三角洲港口、航道及船型的基础上,提出了从南沙至三水3000t集装箱船适宜的最佳航线,旨在为开发新船型作准备,以适应珠江三角洲集装箱运输的发展需要.

  16. The influence of salinity and restoration on wetland soil microbial communities and carbon cycling in the San Francisco Bay-Delta Region

    Science.gov (United States)

    Theroux, S.; Hartman, W.; He, S.; Windham-Myers, L.; Tringe, S. G.

    2014-12-01

    Climate change is predicted to increase the average salinity of the San Francisco Bay-Delta watershed as sea levels rise and alpine snow volume decreases. Wetland soil microbial communities are responsible for cycling greenhouse gases and their response to climate change will heavily influence whether increasing salinity will have a negative or positive effect on the net greenhouse gas budgets of wetlands. To better understand the underlying factors determining the balance of greenhouse gas flux in wetland soils, we targeted the microbial communities along a salinity gradient ranging from freshwater to full seawater in the San Francisco Bay-Delta region. Using DNA and RNA sequencing, coupled with greenhouse gas monitoring, we sampled sixteen sites capturing a range of wetland plant types and restoration states. We determined a suite of soil biogeochemical parameters including moisture, carbon and nutrient contents, pH, sulfate, chloride, and trace metal concentrations. The results of our microbial diversity survey (16S rRNA gene Illumina tag sequencing) showed that salinity and sampling location were the primary drivers of belowground microbial community composition. Freshwater wetland soils, with lower sulfate concentrations, produced more methane than saline sites and we found a parallel increase in the relative abundance of methanogen populations in the high-methane samples. Surprisingly, wetland restoration status did not significantly alter microbial community composition, despite orders of magnitude greater methane flux in restored wetlands compared to reference sites. Deeper metagenomic and metatranscriptomic sequencing in a restored wetland allowed us to further evaluate the roles of methanogen abundance and activity in shaping soil methane production. Our study links belowground microbial communities with their greenhouse gas production, providing a mechanistic microbial framework for assessing climate change feedbacks in wetland soils resulting from sea

  17. Connecting the 'workshop of the world': intra- and extra-service networks of the Pearl River Delta city-region

    NARCIS (Netherlands)

    Zhang, X.; Kloosterman, R.C.

    2016-01-01

    Most research on globalization and city-regions in developing countries has focused on manufacturing activities, disregarding the considerable growth of producer services. Drawing on the Interlocking Network Model, this article presents a first analysis of the intra- and extra-service networks of th

  18. Connecting the 'workshop of the world': intra- and extra-service networks of the Pearl River Delta city-region

    NARCIS (Netherlands)

    Zhang, X.; Kloosterman, R.C.

    2016-01-01

    Most research on globalization and city-regions in developing countries has focused on manufacturing activities, disregarding the considerable growth of producer services. Drawing on the Interlocking Network Model, this article presents a first analysis of the intra- and extra-service networks of th

  19. Delta Electroproduction in 12-C

    Energy Technology Data Exchange (ETDEWEB)

    Steven McLauchlan

    2003-01-31

    The Delta-nucleus potential is a crucial element in the understanding of the nuclear system. Previous electroexcitation measurements in the delta region reported a Q2 dependence of the delta mass indicating that this potential is dependent on the momentum of the delta. Such a dependence is not observed for protons and neutrons in the nuclear medium. This thesis presents the experimental study of the electroexcitation of the delta resonance in 12C, performed using the high energy electron beam at the Thomas Jefferson National Accelerator Facility, and the near 4(pie) acceptance detector CLAS that enables the detection of the full reaction final state. Inclusive, semi inclusive, and exclusive cross sections were measured with an incident electron beam energy of 1.162GeV over the Q2 range 0.175-0.475 (GeV/c)2. A Q2 dependence of the delta mass was only observed in the exclusive measurements indicating that the delta-nucleus potential is affected by the momentum of the delta.

  20. 长三角高职类物流人才核心竞争力研究%Research of Core Competitiveness of Higher Vocational Logistics Talents in Yangtze River Delta Region

    Institute of Scientific and Technical Information of China (English)

    林小芳; 杨玉玉; 王海船; 夏慧玲

    2011-01-01

    长三角地区由于其地理位置显要,交通设施便利,经济发展水平高等特点,其物流优势显现.与其他经济圈不同,长三角以民营企业居多.而企业性质不同,对物流人才的基本素质要求也是不同的.笔者结合长三角物流行业特点,在调查分析的基础上,探讨长三角高职类物流人才核心竞争力,为高职院校物流人才培养方向提供一定的依据.%Due to the characteristics of Yangtze River Delta region, such as prominent geography location, convenient traffic facilities and economic development with high level, its logistics advantage is appearing. Compared to other economic circle, there are many private enterprises in Yangtze River Delta region. However, different nature of enterprise has different requirements for basic quality of logistics talents. Combined with the characteristics of logistics industry in Yangtze River Delta region and based on the investigation and analysis, the author discusses core competitiveness of higher vocational logistics talents in Yangtze River Delta region so as to provide basis for the training direction of logistics talents in higher vocational colleges.

  1. Association between salinity and hospital admission for hypertension: an ecological case-control study in the Mekong Delta Region in Vietnam.

    Science.gov (United States)

    Talukder, Mohammad Radwanur Rahman; Rutherford, Shannon; Chu, Cordia; Hieu Nguyen, Trung; Phung, Dung

    2017-04-13

    Drinking water in the Mekong Delta Region (MDR) is highly vulnerable to salinity intrusion and this problem is expected to increase with the projected climate change and sea level rise. Despite this, research on health effects of saline contaminated water is scarce in this region. This study examines the risk of hospital admission for hypertension in salinity-affected areas of the MDR. Cases and controls were obtained from national/provincial hospital admission records for 2013. The cases were adult patients whom hypertension (ICD10-code: I10-I15) was primary diagnosis for admission. Of the 13 provinces in the MDR, we identified seven as 'salinity exposed' and the remaining as 'non-exposed' areas. A multi-level logistic regression model was used to examine the association between salinity exposure and hypertension outcome. Of the total 573 650 hospital admissions, 22 382 (~3.9%) were hypertensive cases. The multi-level logistic model combining both individual and ecological factors showed a 9% increase in risk (95% CI: 3-14%) of hypertension admission among individuals in exposed areas compared to those in non-exposed areas. In order to develop and promote appropriate adaptation strategies, further research is recommended to identify the salt exposure pathways and consumption behaviours in the salinity exposed areas.

  2. An Algorithm on Convective Weather Potential in the Early Rainy Season over the Pearl River Delta in China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper describes the procedure and methodology to formulate the convective weather potential (CWP) algorithm. The data used in the development of the algorithm are the radar echoes at 0.5° elevation from Guangzhou Doppler Radar Station, surface observations from automatic weather stations (AWS) and outputs of numeric weather prediction (NWP) models. The procedure to develop the CWP algorithm consists of two steps: (1) identification of thunderstorm cells in accordance with specified statistical criteria;and (2) development of the algorithm based on multiple linear regression. The thunderstorm cells were automatically identified by radar echoes with intensity greater than or equal to 50 dB(Z) and of an area over 64 square kilometers. These cells are generally related to severe convective weather occurrences such as thunderstorm wind gusts, hail and tornados. In the development of the CWP algorithm, both echoand environment-based predictors are used. The predictand is the probability of a thunderstorm cell to generate severe convective weather events. The predictor-predictand relationship is established through a stepwise multiple linear regression approach. Verification with an independent dataset shows that the CWP algorithm is skillful in detecting thunderstorm-related severe convective weather occurrences in the Pearl River Delta (PRD) region of South China. An example of a nowcasting case for a thunderstorm process is illustrated.

  3. Application effects of coated urea and urease and nitrification inhibitors on ammonia and greenhouse gas emissions from a subtropical cotton field of the Mississippi delta region.

    Science.gov (United States)

    Tian, Zhou; Wang, Jim J; Liu, Shuai; Zhang, Zengqiang; Dodla, Syam K; Myers, Gerald

    2015-11-15

    Nitrogen (N) fertilization affects both ammonia (NH3) and greenhouse gas (GHG) emissions that have implications in air quality and global warming potential. Different cropping systems practice varying N fertilizations. The aim of this study was to investigate the effects of applications of polymer-coated urea and urea treated with N process inhibitors: NBPT [N-(n-butyl)thiophosphoric triamide], urease inhibitor, and DCD [Dicyandiamide], nitrification inhibitor, on NH3 and GHG emissions from a cotton production system in the Mississippi delta region. A two-year field experiment consisting of five treatments including the Check (unfertilized), urea, polymer-coated urea (ESN), urea+NBPT, and urea+DCD was conducted over 2013 and 2014 in a Cancienne loam (Fine-silty, mixed, superactive, nonacid, hyperthermic Fluvaquentic Epiaquepts). Ammonia and GHG samples were collected using active and passive chamber methods, respectively, and characterized. The results showed that the N loss to the atmosphere following urea-N application was dominated by a significantly higher emission of N2O-N than NH3-N and the most N2O-N and NH3-N emissions were during the first 30-50 days. Among different N treatments compared to regular urea, NBPT was the most effective in reducing NH3-N volatilization (by 58-63%), whereas DCD the most significant in mitigating N2O-N emissions (by 75%). Polymer-coated urea (ESN) and NBPT also significantly reduced N2O-N losses (both by 52%) over urea. The emission factors (EFs) for urea, ESN, urea-NBPT, urea+DCD were 1.9%, 1.0%, 0.2%, 0.8% for NH3-N, and 8.3%, 3.4%, 3.9%, 1.0% for N2O-N, respectively. There were no significant effects of different N treatments on CO2-C and CH4-C fluxes. Overall both of these N stabilizers and polymer-coated urea could be used as a mitigation strategy for reducing N2O emission while urease inhibitor NBPT for reducing NH3 emission in the subtropical cotton production system of the Mississippi delta region.

  4. Hydrological response to urbanization at different spatio-temporal scales simulated by coupling of CLUE-S and the SWAT model in the Yangtze River Delta region

    Science.gov (United States)

    Zhou, Feng; Xu, Youpeng; Chen, Ying; Xu, C.-Y.; Gao, Yuqin; Du, Jinkang

    2013-04-01

    SummaryThe Main objective of the study is to understand and quantify the hydrological responses of land use and land cover changes. The Yangtze River Delta is one of the most developed regions in China with the rapid development of urbanization which serves as an excellent case study site for understanding the hydrological response to urbanization and land use change. The Xitiaoxi River basin, one of the main upstream rivers to the Taihu Lake in the Yangtze River Delta, was selected to perform the study. The urban area in the basin increased from 37.8 km2 in 1985 to 105 km2 in 2008. SWAT model, which makes direct use of land cover and land use data in simulating streamflow, provides as a useful tool for performing such studies and is therefore used in this study. The results showed that (1) the expansion of urban areas had a slight influence on the simulated annual streamflow and evapotranspiration (ET) as far as the whole catchment is concerned; (2) surface runoff and baseflow were found more sensitive to urbanization, which had increased by 11.3% and declined by 11.2%, respectively; (3) changes in streamflow, evapotranspiration and surface runoff were more pronounced during the wet season (from May to August), while baseflow and lateral flow had a slight seasonal variation; (4) the model simulated peak discharge increased 1.6-4.3% and flood volume increased 0.7-2.3% for the selected storm rainfall events at the entire basin level, and the change rate was larger for smaller flood events than for larger events; (5) spatially, changes of hydrological fluxes were more remarkable in the suburban basin which had a relative larger increase in urbanization than in rural sub-basins; and (6) analysis of future scenarios showed the impacts of urbanization on hydrological fluxes would be more obvious with growth in impervious areas from 15% to 30%. In conclusion, the urbanization would have a slight impact on annual water yield, but a remarkable impact was found on surface

  5. Differential utilization of T cell receptor TCR alpha/TCR delta locus variable region gene segments is mediated by accessibility.

    Science.gov (United States)

    Lee, Yu Nee; Alt, Frederick W; Reyes, Julia; Gleason, Megan; Zarrin, Ali A; Jung, David

    2009-10-13

    T cell receptor (TCR) variable region exons are assembled from germline V, (D), and J gene segments, each of which is flanked by recombination signal (RS) sequences that are composed of a conserved heptamer, a spacer of 12 or 23 bp, and a characteristic nonamer. V(D)J recombination only occurs between V, D, and J segments flanked by RS sequences that contain, respectively, 12(12-RS)- and 23(23-RS)-bp spacers (12/23 rule). Additional mechanisms can restrict joining of 12/23 RS matched segments beyond the 12/23 rule (B12/23). The TCRdelta locus is contained within the TCRalpha locus; TCRalpha variable region exons are encoded by TRAV and TRAJ segments and those of TCRdelta by TRDV, TRDD, and TRDJ segments. On the basis of the 12/23 rule, both TRAV and TRDV gene segments are compatible to rearrange with TRDD gene segments; however, TRAV-to-TRDD joins are not observed in vivo. Absence of TRAV-to-TRDD rearrangement might be explained either by B12/23 restriction or by differential accessibility of the TRDV versus TRAV gene segments for rearrangement to TRDD. We used in vitro substrate analysis to reveal that both TRAV and TRDV 23-RSs mediate rearrangements to the 5'TRDD1 12-RS, demonstrating that B12/23 restriction does not explain these rearrangement biases. However, targeted replacement of TRDD1 and its 12-RSs with TRAJ38 and its 12-RS showed that TRDV gene segments rearrange with the ectopic TRAJ38, whereas TRAV segments do not. Our results demonstrate that sorting of TRAV and TRDV gene segments is determined by differential locus accessibility during T cell development.

  6. A novel PRD I and TG binding activity involved in virus-induced transcription of IFN-A genes.

    Science.gov (United States)

    Génin, P; Bragança, J; Darracq, N; Doly, J; Civas, A

    1995-01-01

    Comparative analysis of the inducible elements of the mouse interferon A4 and A11 gene promoters (IE-A4 and IE-A11) by transient transfection experiments, DNase 1 footprinting and electrophoretic mobility shift assays resulted in identification of a virus-induced binding activity suggested to be involved in NDV-induced activation of transcription of these genes. The virus-induced factor, termed VIF, is activated early by contact of virions with cells. It specifically recognizes the PRD I-like domain shared by both inducible elements, as well as the TG-like domain of IE-A4. This factor, distinct from the IRF-1, IRF-2 and the alpha F1 binding proteins and presenting a different affinity pattern from that of the TG protein, is proposed as a candidate for IFN-type I gene regulation. Images PMID:8559665

  7. Estimates of anthropogenic halocarbon emissions based on its measured ratios relative to CO in the Pearl River Delta

    Directory of Open Access Journals (Sweden)

    M. Shao

    2011-01-01

    Full Text Available Using a GC/FID/MS system, we analyzed the mixing ratio levels of 16 halocarbon species in more than 100 air samples collected in 2004 from the Pearl River Delta (PRD region of southern China. The results revealed elevated regional mixing ratios for most halocarbons, especially for HClC = CCl2 (trichloroethylene, TCE, CH2Cl2 (dichloromethane, DCM, CH3Br (bromomethane, HCFC-22, CHCl3 (trichloromethane, CCl4 (tetrachloromethane, Cl2C = CCl2 (perchloroethylene, PCE, CH3CCl3 (methyl chloroform, MCF, and CFC-12. Comparisons were done with the data from TRACE-P and ALE/GAGE/AGAGE experiments, we found that the large variability in concentrations (relative standard deviation ranged from 9.31% to 96.55% of the halocarbons suggested substantial local emissions from the PRD region in 2004. Correlations between the mixing ratio of each species and carbon monoxide (CO were examined, and then each emission of halocarbon was quantified based on scaling the optimized CO emission inventory with the slope of the regression line fitted to each species relative to CO. The calculated results revealed that mass of CH2Cl2 (7.0 Gg, CH3CCl3 (6.7 Gg, and Cl2C = CCl2 (2.3 Gg accounted for about 62.9% of total emissions, suggesting a significant contribution to halocarbon emissions from solvent use in the PRD region. Emissions of HCFC-22 (3.5 Gg, an alternative refrigerant to chlorofluorocarbons (CFCs, were about 2.3 times greater than those of CFC-12 (1.6 Gg. CFC-12 and HCFC-22 accounted for 21.5% of total emissions of halocarbons, so that the refrigerant would be the second largest source of halocarbons. However, the ratio approach found only minor emissions of other CFCs, such as CFC-11, and levels of CFC-114 and CFC-113 were close to zero. Emissions of other anthropogenic halocarbons, such as CCl

  8. Fast increasing of surface ozone concentrations in Pearl River Delta characterized by a regional air quality monitoring network during 2006-2011.

    Science.gov (United States)

    Li, Jinfeng; Lu, Keding; Lv, Wei; Li, Jun; Zhong, Liuju; Ou, Yubo; Chen, Duohong; Huang, Xin; Zhang, Yuanhang

    2014-01-01

    Based on the observation by a Regional Air Quality Monitoring Network including 16 monitoring stations, temporal and spatial variations of ozone (O3), NO2 and total oxidant (O(x)) were analyzed by both linear regression and cluster analysis. A fast increase of regional O3 concentrations of 0.86 ppbV/yr was found for the annual averaged values from 2006 to 2011 in Guangdong, China. Such fast O3 increase is accompanied by a correspondingly fast NO(x) reduction as indicated by a fast NO2 reduction rate of 0.61 ppbV/yr. Based on a cluster analysis, the monitoring stations were classified into two major categories--rural stations (non-urban) and suburban/urban stations. The O3 concentrations at rural stations were relatively conserved while those at suburban/urban stations showed a fast increase rate of 2.0 ppbV/yr accompanied by a NO2 reduction rate of 1.2 ppbV/yr. Moreover, a rapid increase of the averaged O3 concentrations in springtime (13%/yr referred to 2006 level) was observed, which may result from the increase of solar duration, reduction of precipitation in Guangdong and transport from Eastern Central China. Application of smog production algorithm showed that the photochemical O3 production is mainly volatile organic compounds (VOC)-controlled. However, the photochemical O3 production is sensitive to both NO(x) and VOC for O3 pollution episode. Accordingly, it is expected that a combined NO(x) and VOC reduction will be helpful for the reduction of the O3 pollution episodes in Pearl River Delta while stringent VOC emission control is in general required for the regional O3 pollution control.

  9. Detection of avian H7N9 influenza A viruses at the Yangtze Delta Region of China during early H7N9 outbreaks

    Science.gov (United States)

    Li, Yin; Huang, Xin-mei; Zhao, Dong-min; Liu, Yu-zhuo; He, Kong-wang; Liu, Yao-xing; Chen, Chang-hai; Long, Li-Ping; Xu, Yifei; Xie, Xing-xing; Han, Kai-kai; Liu, Xiao-yan; Yang, Jing; Zhang, You-Fa; Fan, Feng; Webby, Richard; Wan, Xiu-Feng

    2016-01-01

    SUMMARY Since the first H7N9 human case in Shanghai, February 19, 2013, the emerging avian-origin H7N9 influenza A virus has become an epizootic virus in China, posing a potential pandemic threat to public health. From April 2 to April 28, 2013, 422 oral-pharyngeal and cloacal swabs were collected from birds and environmental surfaces at five live poultry markets (LPMs) and 13 backyard poultry farms (BPFs) across three cities, Wuxi, Suzhou, and Nanjing, in the Yangtze Delta Region. A total of 22 isolates were recovered, and 6 were subtyped as H7N9, 9 as H9N2, 4 as H7N9/H9N2, and 3 un-subtyped influenza A viruses. Genomic sequences showed that the HA and NA genes of the H7N9 viruses were similar to those of the H7N9 human isolates as well as other avian origin H7N9 isolates in the region but the PB1, PA, NP, and MP genes of the sequenced viruses were, however, more diverse. Among the four H7N9/H9N2 mixed infections, three were from LPM whereas the other one from the ducks at one BPF, which were H7N9 negative in serological analyses. A survey of the bird trading records of the LPMs and BPFs indicates that trading was a likely route for virus transmission across these regions. Our results suggested that a better biosecurity and more effective vaccination should be implemented in backyard farms besides biosecurity management in LPMs. PMID:27309047

  10. Detection of Avian H7N9 Influenza A Viruses in the Yangtze Delta Region of China During Early H7N9 Outbreaks.

    Science.gov (United States)

    Li, Yin; Huang, Xin-Mei; Zhao, Dong-Min; Liu, Yu-Zhuo; He, Kong-Wang; Liu, Yao-Xing; Chen, Chang-Hai; Long, Li-Ping; Xu, Yifei; Xie, Xing-Xing; Han, Kai-Kai; Liu, Xiao-Yan; Yang, Jing; Zhang, You-Fa; Fan, Feng; Webby, Richard; Wan, Xiu-Feng

    2016-05-01

    Since the first H7N9 human case in Shanghai, February 19, 2013, the emerging avian-origin H7N9 influenza A virus has become an epizootic virus in China, posing a potential pandemic threat to public health. From April 2 to April 28, 2013, some 422 oral-pharyngeal and cloacal swabs were collected from birds and environmental surfaces at five live poultry markets (LPMs) and 13 backyard poultry farms (BPFs) across three cities, Wuxi, Suzhou, and Nanjing, in the Yangtze Delta region. In total 22 isolates were recovered, and six were subtyped as H7N9, nine as H9N2, four as H7N9/H9N2, and three unsubtyped influenza A viruses. Genomic sequences showed that the HA and NA genes of the H7N9 viruses were similar to those of the H7N9 human isolates, as well as other avian-origin H7N9 isolates in the region, but the PB1, PA, NP, and MP genes of the sequenced viruses were more diverse. Among the four H7N9/H9N2 mixed infections, three were from LPM, whereas the other one was from the ducks at one BPF, which were H7N9 negative in serologic analyses. A survey of the bird trading records of the LPMs and BPFs indicates that trading was a likely route for virus transmission across these regions. Our results suggested that better biosecurity and more effective vaccination should be implemented in backyard farms, in addition to biosecurity management in LPMs.

  11. Development and uncertainty analysis of a high-resolution NH3 emissions inventory and its implications with precipitation over the Pearl River Delta region, China

    Directory of Open Access Journals (Sweden)

    W. W. Che

    2011-12-01

    Full Text Available Detailed NH3 emission inventories are important to understand various atmospheric processes, air quality modeling study, air pollution management, and related environmental and ecological issues. A high-resolution NH3 emission inventory is developed based on the state-of-the-science techniques, the up-to-date information, and the advanced expert knowledge for the Pearl River Delta region, China. To provide model-ready emissions input, this NH3 emissions inventory is spatially allocated to 3 km × 3 km grid cells using source-based spatial surrogates with Geographical Information System (GIS technology. For NH3 emissions, 9 source categories and 45 sub-categories are identified in this region, and detailed spatial and temporal characteristics are investigated. Results show that livestock is by far the most important NH3 emission source that contributes about 61.7% of the total NH3 emissions in this region, followed by nitrogen fertilizer applications (~23.7% and non-agricultural sources (~14.6%. Uncertainty analysis reveals that the uncertainties associated with different sources vary from source to source and the magnitude of the uncertainty associated with a specific source mainly depends on the degree of accuracy of the emission factors and activity data as well as the technique used to perform the estimate. The validity of the NH3 emissions inventory is justified by the trend analysis of local rainwater compositions, especially pH values, the Ca2+ + NH4+/SO42− + NO3− ratios, and NH4+ concentrations which are directly or indirectly related to NH3 emissions. Based on the analysis, recommendations for additional work to further improve the accuracy of the NH3 emissions inventory are also discussed and proposed.

  12. Study on the Training Mode of Innovative Talents in Industry Transfer of PRD%珠三角产业转移中的创新型人才培养模式研究

    Institute of Scientific and Technical Information of China (English)

    魏国平; 邓彦; 李华军

    2011-01-01

    Essentially, industry transfer is the productivity in spatial layout, and the human capital plays a critical role of the adjustment for a successful industrial transfer. Based on the background of the Pearl River Delta industrial transfer, this paper discusses the industrial transfer in innovative talent training in local colleges and universities, from the perspective of the innovative talent, the industrial transfer and the inner mechanism of human capital, and then proposes some countermeasures for training innovative talents in the transfer of PRD industry.%产业转移,本质上是现有生产力在空间布局上的调整,其中人力资本对产业转移成功与否起到关键的作用.在珠三角产业转移的背景下,站在地方高校视角探讨产业转移需要的创新型人才培养模式,从分析创新性人才的必要性、产业转移与人力资本的内在机理出发,提出珠三角产业转移中创新型人才培养的相关对策.

  13. Antibiotics in riverine runoff of the Pearl River Delta and Pearl River Estuary, China: concentrations, mass loading and ecological risks.

    Science.gov (United States)

    Xu, Weihai; Yan, Wen; Li, Xiangdong; Zou, Yongde; Chen, Xiaoxiang; Huang, Weixia; Miao, Li; Zhang, Ruijie; Zhang, Gan; Zou, Shichun

    2013-11-01

    Ten antibiotics belonging to three groups (macrolides, fluoroquinolones and sulfonamides) were investigated in riverine runoff of the Pearl River Delta (PRD) and Pearl River Estuary (PRE), South China for assessing the importance of riverine runoff in the transportation of contaminants from terrestrial sources to the open ocean. All antibiotics were detected in the eight outlets with concentrations ranging from 0.7 to 127 ng L(-1). The annual mass loadings of antibiotics from the PRD to the PRE and coast were 193 tons with 102 tons from the fluoroquinolone group. It showed that antibiotics decreased from the riverine outlets to the PRE and open ocean. Risk assessment showed that most of these antibiotics showed various ecological risks to the relevant aquatic organisms, in which ofloxacin (OFL), erythromycin (ETM) and ciprofloxacin (CIP) posed high ecological risks to the studied aquatic environments.

  14. Non-structural proteins P17 and P33 are involved in the assembly of the internal membrane-containing virus PRD1

    Energy Technology Data Exchange (ETDEWEB)

    Karttunen, Jenni; Mäntynen, Sari [Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä (Finland); Ihalainen, Teemu O. [Stem Cells in Neurological Applications Group, BioMediTech, University of Tampere, Tampere (Finland); Bamford, Jaana K.H. [Centre of Excellence in Biological Interactions, Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä (Finland); Oksanen, Hanna M., E-mail: hanna.oksanen@helsinki.fi [Institute of Biotechnology and Department of Biosciences, University of Helsinki, Biocenter 2, P.O. Box 56 (Viikinkaari 5), FIN-00014 Helsinki (Finland)

    2015-08-15

    Bacteriophage PRD1, which has been studied intensively at the structural and functional levels, still has some gene products with unknown functions and certain aspects of the PRD1 assembly process have remained unsolved. In this study, we demonstrate that the phage-encoded non-structural proteins P17 and P33, either individually or together, complement the defect in a temperature-sensitive GroES mutant of Escherichia coli for host growth and PRD1 propagation. Confocal microscopy of fluorescent fusion proteins revealed co-localisation between P33 and P17 as well as between P33 and the host chaperonin GroEL. A fluorescence recovery after photobleaching assay demonstrated that the diffusion of the P33 fluorescent fusion protein was substantially slower in E. coli than theoretically calculated, presumably resulting from intermolecular interactions. Our results indicate that P33 and P17 function in procapsid assembly, possibly in association with the host chaperonin complex GroEL/GroES. - Highlights: • Two non-structural proteins of PRD1 are involved in the virus assembly. • P17 and P33 complement the defect in GroES of Escherichia coli. • P33 co-localises with GroEL and P17 in the bacterium. • Slow motion of P33 in the bacterium suggests association with cellular components.

  15. In situ detection of the chemistry of individual fog droplet residues in the Pearl River Delta region, China

    Science.gov (United States)

    Bi, Xinhui; Lin, Qinhao; Peng, Long; Zhang, Guohua; Wang, Xinming; Brechtel, Fred J.; Chen, Duohong; Li, Mei; Peng, Ping'an; Sheng, Guoying; Zhou, Zhen

    2016-08-01

    We use a single-particle aerosol mass spectrometer coupled with a ground-based counterflow virtual impactor to measure the chemical compositions of individual submicron fog droplet residues. This is the first report on single particle mass spectrometry measurements of fog droplet residual particles at ground level in an urban area. We show that most of the fog droplet residues were composed of elemental carbon (EC) (67.7%), followed by K-rich (19.2%) and mineral dust/metal (12.3%) particles. The predominance of EC-containing particles demonstrated that these particles could be effective fog nuclei and highlights the important influence of anthropogenic emissions on regional climate system. Compared with interstitial and ambient aerosols, nitrate was enhanced, sulfate was depressed, and ammonium- and organics-containing particles were hardly found in the fog droplet residues during fog events, suggesting that dust and metal particles containing nitrate may be preferentially activated and that ammonium and organics may not play important roles in fog formation in Guangzhou. We also present direct observational evidence that trimethylamine and hydroxymethanesulfonate are not found within fog droplet residues, although we previously observed enhanced gas-to-particle partitioning of these compounds by fog processing. Additionally, higher fraction or intensities of [K]+, [Fe]+, and [SiO3]- were found in fog droplet residues than in ambient and interstitial particles.

  16. Solar Magnetic Field Studies Using the 12-Micron Emission Lines. IV. Observations of a Delta-Region Solar Flare

    CERN Document Server

    Jennings, D E; McCabe, G; Sada, P; Moran, T; Jennings, Donald E.; Deming, Drake; Sada, Pedro; Moran, Thomas

    2002-01-01

    We have recently developed the capability to make solar vector (Stokes IQUV) magnetograms using the infrared line of MgI at 12.32 microns. On 24 April 2001, we obtained a vector magnetic map of solar active region NOAA 9433, fortuitously just prior to the occurrence of an M2 flare. Examination of a sequence of SOHO/MDI magnetograms, and comparison with ground-based H-alpha images, shows that the flare was produced by the cancellation of newly emergent magnetic flux outside of the main sunspot. The very high Zeeman-sensitivity of the 12-micron data allowed us to measure field strengths on a spatial scale which was not directly resolvable. At the flare trigger site, opposite polarity fields of 2700 and 1000 Gauss occurred within a single 2 arc-sec resolution element, as revealed by two resolved Zeeman splittings in a single spectrum. Our results imply an extremely high horizontal field strength gradient (5 G/km) prior to the flare, significantly greater than seen in previous studies. We also find that the magne...

  17. Assessment of organochlorine pesticide contamination in relation to soil properties in the Pearl River Delta, China.

    Science.gov (United States)

    Yu, Huan-Yun; Li, Fang-Bai; Yu, Wei-Min; Li, Yong-Tao; Yang, Guo-Yi; Zhou, Shun-Gui; Zhang, Tian-Bin; Gao, Yuan-Xue; Wan, Hong-Fu

    2013-03-01

    High levels of organochlorine pesticides (OCPs) such as hexachlorocyclohexanes (HCHs) and dichlorodiphenyltrichloroethanes (DDTs) have been found in soil of the Pearl River Delta (PRD), attributable to high pesticide application in this area. Consequently, the occurrence and environmental effect of HCHs and DDTs in the PRD have attracted considerable attention. However, study focusing on the influence of potential factors such as soil property on the environmental fate of HCHs and DDTs in the PRD has been rare. The present study aimed to investigate the impact of soil physiochemical properties on the distribution patterns and fate of soil HCHs and DDTs on a large spatial scale. Levels of HCHs (sum of α-, β-, γ- and δ-HCH) and DDTs (sum of 1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane (p,p'-DDT), 1,1-dichloro-2,2-bis-(p-chlorophenyl)ethane (p,p'-DDD), and 1,1-dichloro-2,2-bis-(p-chlorophenyl)ethylene (p,p'-DDE)) in 151 soil samples covering all areas of the PRD and physiochemical parameters related to soil properties including pH, total organic carbon (TOC), total Fe (TFe), DCB-Fe (DFe), amorphous-Fe (AFe), complexed-Fe (CFe), total Mn (TMn), DCB-Mn (DMn), amorphous-Mn (AMn), complexed-Mn (CMn) and cation exchange capacity (CEC) were determined. The residual levels of HCHs and DDTs in soils of the present study, which are mainly controlled by soil TOC and CFe content and varying spatially with land use types, may potentially pose ecological risk to plants and animals. On the other hand, transformation of soil HCHs may be affected by pH and DDT transformation correlated significantly with AFe and CFe. Currently, soil has become an important secondary source of OCPs and the re-emission potential of OCPs in soil was mainly affected by soil OCP concentrations and land use types.

  18. Measurements of volatile organic compounds in rural area of Yangtze River Delta region: Measurement comparison and source characterization

    Science.gov (United States)

    Kudo, S.; Saito, S.; Tanimoto, H.; Inomata, S.; Kanaya, Y.; Yamaji, K.; Xiaole, P.; Wang, Z.

    2012-12-01

    Concentrations of non-methane volatile organic compounds (NMVOCs) in ambient air were measured by three different methods in a city of Rudong in May and June 2010. Intercomparison of VOCs measurements was made among in-situ measurements and canister analyses with a gas chromatography/flame ionization detection/mass spectrometry (GC/FID/MS) and proton transfer reaction-mass spectrometry (PTR-MS). For 18 VOCs measured by GC/FID/MS, canister analyses and in-situ measurements were in reasonably good agreement (R2 > 0.90). However, alkenes and aromatics in canister samples were found to be lower than in-situ measurements likely due to adsorption of low volatile compounds onto the wall surface inside canisters. For comparison of GC/MS with PTR-MS, the correlations for isoprene, benzene, C8 aromatics, and C9 aromatics were highly significant (R2 ≥ 0.93) with each other. However, there were quantitative differences between GC/MS and PTR-MS. For example, isoprene measured by PTR-MS indicates existence of interferences from C5 alcohols, C5 aldehydes, and furan. During the latter part of the field campaign, elevated concentrations of VOCs and CO were observed when intensive burning of crop residues took place near the sampling site. The concentrations of ethane, propane, ethane, isoprene, acetone, acetaldehyde, and aromatics varied in the range between 0 and 30 ppbv. The observed VOCs concentrations are compared to model results by a regional chemistry-transport model for Asia. The modeled concentrations underestimated the observed concentrations by a factor of 10 for NMHCs, 100 for aromatics, 10 for oxygenated VOCs, implying that current emissions inventories miss a number of sources for these VOCs.

  19. Numerical groundwater-flow modeling to evaluate potential effects of pumping and recharge: implications for sustainable groundwater management in the Mahanadi delta region, India

    Science.gov (United States)

    Sahoo, Sasmita; Jha, Madan K.

    2017-07-01

    Process-based groundwater models are useful to understand complex aquifer systems and make predictions about their response to hydrological changes. A conceptual model for evaluating responses to environmental changes is presented, considering the hydrogeologic framework, flow processes, aquifer hydraulic properties, boundary conditions, and sources and sinks of the groundwater system. Based on this conceptual model, a quasi-three-dimensional transient groundwater flow model was designed using MODFLOW to simulate the groundwater system of Mahanadi River delta, eastern India. The model was constructed in the context of an upper unconfined aquifer and lower confined aquifer, separated by an aquitard. Hydraulic heads of 13 shallow wells and 11 deep wells were used to calibrate transient groundwater conditions during 1997-2006, followed by validation (2007-2011). The aquifer and aquitard hydraulic properties were obtained by pumping tests and were calibrated along with the rainfall recharge. The statistical and graphical performance indicators suggested a reasonably good simulation of groundwater flow over the study area. Sensitivity analysis revealed that groundwater level is most sensitive to the hydraulic conductivities of both the aquifers, followed by vertical hydraulic conductivity of the confining layer. The calibrated model was then employed to explore groundwater-flow dynamics in response to changes in pumping and recharge conditions. The simulation results indicate that pumping has a substantial effect on the confined aquifer flow regime as compared to the unconfined aquifer. The results and insights from this study have important implications for other regional groundwater modeling studies, especially in multi-layered aquifer systems.

  20. Measurement of the Polarized Structure Function $\\sigma_{LT^\\prime}$ for $p(\\vec{e},e'\\pi^+)n$ in the $\\Delta(1232)$ Resonance Region

    CERN Document Server

    Joo, K; Aznauryan, I G; Burkert, V D; Minehart, R C; Adams, G; Ambrozewicz, P; Anciant, E; Anghinolfi, M; Asavapibhop, B; Asryan, G; Audit, G; Auger, T; Avakian, H; Bagdasaryan, H; Ball, J P; Barrow, S; Batourine, V; Battaglieri, M; Beard, K; Bektasoglu, M; Benmouna, N; Bianchi, N; Biselli, A S; Boiarinov, S; Bonner, B E; Bouchigny, S; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Bültmann, S; Butuceanu, C; Calarco, J R; Carman, D S; Carnahan, B; Cetina, C; Chen, S; Ciciani, L; Cole, P L; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Cummings, J P; De Sanctis, E; De Vita, R; Degtyarenko, P V; Dennis, L; Deur, A; Dharmawardane, K V; Dhuga, K S; Djalali, C; Dodge, G E; Doughty, D; Dragovitsch, P; Dugger, M; Dytman, S; Dzyubak, O P; Egiyan, H; Egiyan, K S; Elouadrhiri, L; Empl, A; Eugenio, P; Fersch, R; Feuerbach, R J; Forest, T A; Funsten, H; Gaff, S J; Garçon, M; Gavalian, G; Gilad, S; Gilfoyle, G P; Giovanetti, K L; Gothe, R W; Griffioen, K A; Guidal, M; Guillo, M R; Guler, N; Guo, L; Gyurjyan, V; Hadjidakis, C; Hakobyan, R S; Hardie, J; Heddle, D; Hersman, F W; Hicks, K; Hleiqawi, I; Holtrop, M; Hu, J; Hyde-Wright, C E; Ilieva, Y; Ireland, D; Ito, M M; Jenkins, D; Jüngst, H G; Kellie, J D; Kelley, J H; Khandaker, M; Kim, K Y; Kim, K; Kim, W; Klein, A; Klein, F J; Klimenko, A V; Klusman, M; Kossov, M; Koubarovski, V; Kramer, L H; Kuhn, S E; Kühn, J; Lachniet, J; Laget, J M; Langheinrich, J; Lawrence, D; Lee, T; Livingston, K; Lukashin, K; Manak, J J; Marchand, C; McAleer, S; McNabb, J W C; Mecking, B A; Mestayer, M D; Meyer, C A; Mikhailov, K; Mirazita, M; Miskimen, R; Mokeev, V; Morand, L; Morrow, S A; Muccifora, V; Müller, J; Mutchler, G S; Napolitano, J; Nasseripour, R; Nelson, S O; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niyazov, R A; Nozar, M; O'Rielly, G V; Osipenko, M; Ostrovidov, A I; Park, K; Pasyuk, E A; Peterson, G; Philips, S A; Pivnyuk, N; Pocanic, D; Pogorelko, O I; Polli, E; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ritchie, B G; Ronchetti, F; Rosner, G; Rossi, P; Rowntree, D; Rubin, P D; Sabatie, F; Sabourov, K; Salgado, C; Santoro, J P; Sapunenko, V; Schumacher, R A; Serov, V S; Sharabyan, Yu G; Shaw, J; Simionatto, S; Skabelin, A V; Smith, E S; Sober, D I; Spraker, M; Stavinsky, A V; Stepanyan, S; Stokes, B E; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Taylor, S; Tedeschi, D J; Thoma, U; Thompson, R; Tkabladze, A; Todor, L; Tur, C; Ungaro, M; Vineyard, M F; Vlassov, A V; Wang, K; Weinstein, L B; Weller, H; Weygand, D P; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Yun, J; Zana, L

    2004-01-01

    The polarized longitudinal-transverse structure function $\\sigma_{LT^\\prime}$ has been measured using the $p(\\vec e,e'\\pi^+)n$ reaction in the $\\Delta(1232)$ resonance region at $Q^2=0.40$ and 0.65 GeV$^2$. No previous $\\sigma_{LT^\\prime}$ data exist for this reaction channel. The kinematically complete experiment was performed at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. A partial wave analysis of the data shows generally better agreement with recent phenomenological models of pion electroproduction compared to the previously measured $\\pi^0 p$ channel. A fit to both $\\pi^0 p$ and $\\pi^+ n$ channels using a unitary isobar model suggests the unitarized Born terms provide a consistent description of the non-resonant background. The $t$-channel pion pole term is important in the $\\pi^0 p$ channel through a rescattering correction, which could be model-dependent.

  1. Understanding culture in territorial management and its implications for spatial planning. The case of floodplain management in urbanised delta regions in the Netherlands and Thailand

    Directory of Open Access Journals (Sweden)

    Suwanna Rongwiriyaphanich

    2014-08-01

    to investigate whether culture is an important element (or context variable explaining planning practices and territorial management outcomes in different settings. These perspectives are the analysis
that assumes a stable state of culture (a synchronic perspective and the analysis that considers culture as dynamic and interrelating with other context variables (a diachronic perspective. Findings derived from the analysis of the case studies based on these two perspectives help draw theoretical conclusions about how planners may deal with culture in order to improve planning practices.The study investigates territorial development processes in the context of floodplain management in urbanised delta regions. This specific context is selected because of its strong relations between physical attributes and spatial planning activities. The analysis is carried out based on a comparative approach at two levels. At the cross-national level, the Rhine-Meuse delta region in the Netherlands and the Chaophraya delta region in Thailand are used as case studies. The comparative approach is useful for this study because culture can be best understood in a relative form. The sub- national analysis emphasises comparison of floodplain management in three selected districts in the Chaophraya delta region. The two levels of analysis are carried out in order to understand whether the influences of cultures on planning practices and territorial management outcomes at different scales of development are affected by similar elements. Besides the theoretical contribution, this study also contributes methodologically through development of a common conceptual framework that can be applied to the analysis of various issues in territorial management, which is not limited only to the subject studied here. The framework is also expected to be applicable for the analysis of territorial management in a diverse range of cultural settings.The findings derived from a synchronic analytical approach

  2. Genotoxic biomonitoring study of population residing in pesticide contaminated regions in Göksu Delta: micronucleus, chromosomal aberrations and sister chromatid exchanges.

    Science.gov (United States)

    Ergene, Serap; Celik, Ayla; Cavaş, Tolga; Kaya, Filiz

    2007-10-01

    Pesticides are widely used throughout the world in agriculture to protect crops and in public health to control diseases. Nevertheless, exposure to pesticides represents a potential risk to humans. This paper describes a study of possible genetic damage in the people living in regions contaminated with complex mixture of pesticides in Göksu Delta. In this study, used methods were chromosomal aberration (CA), sister chromatid exchange analysis (SCE) in the peripheral blood lymphocytes, and micronucleus (MN) assay in the buccal epithelial cells. In the present investigation, 32 affected subjects consist of 16 smoking and 16 non-smokings and an equal number of control subjects were assessed for genome damage. Micronucleus (MN), Broken egg (BE), Karyorrhexis (KR), Karyolysis (KL) and Binucleus (BN) frequencies were higher in affected subjects than in controls. Smoking had a statistically significant effect on the Micronucleus, Karyorrhexis and Binucleus frequencies for both the control and the exposed group. Also smoking and exposure affected the frequency of sister chromatid exchange and chromosomal aberrations compared with control groups.

  3. Some aspects of breeding habits of the red-vented bulbul (Pycnonotus Cafer in the Cauvery delta region of southern India

    Directory of Open Access Journals (Sweden)

    P. Radhakrishnan

    2014-06-01

    Full Text Available Breeding habits of the Red-vented Bulbul (Pycnonotus cafer was studied in a portion of Cauvery delta region of Nagapattinam District, Southern India during 2012 to 2013. A total of 52 active nests were located in the study area out of which majority of nests (56.5% were in the  fork  of trees followed by middle of the trees (28.3% and  the top (15.2% of the trees. Preferred nest height (60% by the Red-vented Bulbul was 2-4m from the ground. Plant species used for nest building by the Red-vented Bulbul was Azadirachta indica, Hibiscus rosasinensis, Morinda tinctoria, Lawsonia inermis, Commiphora caudate, Croton bonplandianum and Musa paradisiaca.  The clutch size varied from 2 to 4. Mean incubation period was 12.5 ± 0.85 days and both sexes took part in the incubation. The mean hatching, fledgling and breeding success was 79.3%, 80% and 63.4% respectively.

  4. Process analysis of regional ozone formation over the Yangtze River Delta, China using the Community Multi-scale Air Quality modeling system

    Directory of Open Access Journals (Sweden)

    L. Li

    2012-11-01

    Full Text Available A high O3 episode was detected in urban Shanghai, a typical city in the Yangtze River Delta (YRD region in August 2010. The CMAQ integrated process rate method is applied to account for the contribution of different atmospheric processes during the high pollution episode. The analysis shows that the maximum concentration of ozone occurs due to transport phenomena, including vertical diffusion and horizontal advective transport. Gas-phase chemistry producing O3 mainly occurs at the height of 300–1500 m, causing a strong vertical O3 transport from upper levels to the surface layer. The gas-phase chemistry is an important sink for O3 in the surface layer, coupled with dry deposition. Cloud processes may contribute slightly to the increase of O3 due to convective clouds or to the decrease of O3 due to scavenging. The horizontal diffusion and heterogeneous chemistry contributions are negligible during the whole episode. Modeling results show that the O3 pollution characteristics among the different cities in the YRD region have both similarities and differences. During the buildup period, the O3 starts to appear in the city regions of the YRD and is then transported to the surrounding areas under the prevailing wind conditions. The O3 production from photochemical reaction in Shanghai and the surrounding area is most significant, due to the high emission intensity in the large city; this ozone is then transported out to sea by the westerly wind flow, and later diffuses to rural areas like Chongming island, Wuxi and even to Nanjing. The O3 concentrations start to decrease in the cities after sunset, due to titration of the NO emissions, but ozone can still be transported and maintain a significant concentration in rural areas and even regions outside the YRD region, where the NO emissions are very small.

  5. Long-term Trend of Tropospheric Ozone over the Yangtze Delta Region of China%长江三角洲地区对流层臭氧的变化趋势

    Institute of Scientific and Technical Information of China (English)

    徐晓斌; 林伟立; 王韬

    2007-01-01

    Analysis of tropospheric ozone residual (TOR) data from satellite measurements indicates an increasing trend of tropospheric ozone over the Yangtze Delta region of China. The increasing trend can be derived both from the annual mean TOR and from the monthly mean TOR except for January and March. The increase rate of the decadal mean TOR was 0.82 DU during 1978-2000. The impact of this long-term trend on the climate and atmospheric oxidizing capacity over the region should be further studied. Data comparison shows a significant correlation between the TOR and surface ozone data collected at Lin'an background station in the Yangtze Delta region, suggesting an internal connection between both quantities.

  6. 珠三角地区普通高校体育课程瑜伽教学现状与对策研究%PRD Current Situation of College Sports Course Yoga Teaching and Countermeasures

    Institute of Scientific and Technical Information of China (English)

    李群凤

    2015-01-01

    瑜伽是集健、力、美于一体的一项体育运动,颇受当代大学生的欢迎和青睐。本文以珠三角地区的普通高校公共体育课程瑜伽教学为研究对象,运用文献资料、问卷调查、专家访谈等研究方法,对珠三角地区普通高校公共体育课程中瑜伽教学现状进行深入研究,发现其中存在的问题,并在此基础之上提出建设性的意见,为促进珠三角地区普通高校公共体育课程的教学改革提供新的思路。%Yoga is one kind of sport with an integrtion of health ,power and beauty being popular with contemporary college students .This paper ,taking the Pearl River Delta College public sports curriculum teaching yoga for the example ,using literature ,questionnaire survey ,ex‐pert interviews and other research methods ,studied the Pearl River Delta College Public Sport Course in Yoga Teaching Situation ,eventurally found some problems and then proposed constructive comments on this basis to provide new ideas for promoting the teaching reform in PRD or‐dinary college PE courses .

  7. High time-resolved elemental components in fine and coarse particles in the Pearl River Delta region of Southern China: Dynamic variations and effects of meteorology.

    Science.gov (United States)

    Zhou, Shengzhen; Davy, Perry K; Wang, Xuemei; Cohen, Jason Blake; Liang, Jiaquan; Huang, Minjuan; Fan, Qi; Chen, Weihua; Chang, Ming; Ancelet, Travis; Trompetter, William J

    2016-12-01

    Hourly-resolved PM2.5 and PM10-2.5 samples were collected in the industrial city Foshan in the Pearl River Delta region, China. The samples were subsequently analyzed for elemental components and black carbon (BC). A key purpose of the study was to understand the composition of particulate matter (PM) at high-time resolution in a polluted urban atmosphere to identify key components contributing to extreme PM concentration events and examine the diurnal chemical concentration patterns for air quality management purposes. It was found that BC and S concentrations dominated in the fine mode, while elements with mostly crustal and oceanic origins such as Si, Ca, Al and Cl were found in the coarse size fraction. Most of the elements showed strong diurnal variations. S did not show clear diurnal variations, suggesting regional rather than local origin. Based on empirical orthogonal functions (EOF) method, 3 forcing factors were identified contributing to the extreme events of PM2.5 and selected elements, i.e., urban direct emissions, wet deposition and a combination of coarse mode sources. Conditional probability functions (CPF) were performed using wind profiles and elemental concentrations. The CPF results showed that BC and elemental Cl, K, Fe, Cu and Zn in the fine mode were mostly from the northwest, indicating that industrial emissions and combustion were the main sources. For elements in the coarse mode, Si, Al, K, Ca, Fe and Ti showed similar patterns, suggesting same sources such as local soil dust/construction activities. Coarse elemental Cl was mostly from the south and southeast, implying the influence of marine aerosol sources. For other trace elements, we found vanadium (V) in fine PM was mainly from the sources located to the southeast of the measuring site. Combined with CPF results of S and V in fine PM, we concluded shipping emissions were likely an important elemental emission source.

  8. Study on the Regional Tourism Integration of the Yangtze River Delta for the Shanghai World Exposition%上海世博会后长三角区域旅游一体化的研究

    Institute of Scientific and Technical Information of China (English)

    林武

    2011-01-01

    在经济全球化、区域联动化的背景下,长三角区域旅游经济一体化已成为该地区旅游经济发展的必然趋势。结合2010年上海世博会的召开,分析了长三角区域旅游一体化的现状,指出了世博会对长三角区域旅游一体化的影响,并提出了长三角区域旅游一体化的策略。%Against the background of economic globalization and regional unified actions,the regional tourism economic integration of in Yangtze River Delta has become the inevitable trend for the development of tourism economy for this region.In light of the 2010 Shanghai World Expo,this paper analyzes the current situation of the Yangtze River Delta regional tourism integration,advocates the impact from the World Expo on it,and proposes the strategy for the Yangtze River Delta regional tourism integration.

  9. Differences in basal and morphine-induced FosB/DeltaFosB and pCREB immunoreactivities in dopaminergic brain regions of alcohol-preferring AA and alcohol-avoiding ANA rats.

    Science.gov (United States)

    Kaste, Kristiina; Kivinummi, Tanja; Piepponen, T Petteri; Kiianmaa, Kalervo; Ahtee, Liisa

    2009-06-01

    Besides alcohol, alcohol-preferring AA and alcohol-avoiding ANA rats differ also with respect to other abused drugs. To study the molecular basis of these differences, we examined the expression of two transcription factors implicated in addiction, DeltaFosB and pCREB, in brain dopaminergic regions of AA and ANA rats. The effects of morphine and nicotine were studied to relate the behavioral and molecular changes induced by these drugs. Baseline FosB/DeltaFosB immunoreactivity (IR) in the nucleus accumbens core and pCREB IR in the prefrontal cortex (PFC) were elevated in AA rats. Morphine increased DeltaFosB-like IR more readily in the caudate-putamen of AA rats than in ANA rats. In the PFC morphine decreased pCREB IR in AA rats, but increased it in ANA rats. In addition to enhanced locomotor response, the development of place preference to morphine was enhanced in AA rats. The enhanced nicotine-induced locomotor sensitization found in AA compared with ANA rats seems to depend in addition to dopamine and DeltaFosB on other mechanisms. These findings suggest that enhanced sensitivity of AA rats to morphine is related to augmented morphine-induced expression of FosB/DeltaFosB and morphine-induced reduction of pCREB levels. Moreover, altered innate expression of FosB/DeltaFosB and pCREB in AA rats is likely to affect the sensitivity of these rats to abused drugs.

  10. GIS and Remote Sensing Applications in the Assessment of Change within a Coastal Environment in the Niger Delta Region of Nigeria

    Directory of Open Access Journals (Sweden)

    Edmund C. Merem

    2006-03-01

    Full Text Available In the last decades, the Niger Delta region has experienced rapid growth in population and economicv activity with enormous benefits to the adjacent states and the entire Nigerian society. As the region embarks upon an unprecedented phase of economic expansion in the 21st century, it faces several environmental challenges fuelled partly by the pressures caused by human activities such as oil and gas exploration, housing development, and road construction for transportation, economic development and demographic changes. This continued growth has resulted in environmental problems such as coastal wetland loss, habitat degradation, and water pollution, gas flaring, destruction of forest vegetation as well as a host of other issues. This underscores the urgent need to design new approaches for managing remote costal resources in sensitive tropical environments effectively in order to maintain a balance between coastal resource conservation and rapid economic development in developing countries for sustainability. Notwithstanding previous initiatives, there have not been any major efforts in the literature to undertake a remote sensing and GIS based assessment of the growing incidence of environmental change within coastal zone environments of the study area. This project is an attempt to fill that void in the literature by exploring the applications of GIS and remote sensing in a tropical coastal zone environment with emphasis on the environmental impacts of development in the Niger Delta region of Southern Nigeria. To deal with some of the aforementioned issues, several research questions that are of great relevance to the paper have been posed. The questions include, Have there been any changes in the coastal environment of the study area? What are the impacts of the changes? What forces are responsible for the changes? Has there been any major framework in place to deal with the changes? The prime objective of the paper is to provide a novel

  11. Migration in Deltas: An Integrated Analysis

    Science.gov (United States)

    Nicholls, Robert J.; Hutton, Craig W.; Lazar, Attila; Adger, W. Neil; Allan, Andrew; Arto, Inaki; Vincent, Katharine; Rahman, Munsur; Salehin, Mashfiqus; Sugata, Hazra; Ghosh, Tuhin; Codjoe, Sam; Appeaning-Addo, Kwasi

    2017-04-01

    Deltas and low-lying coastal regions have long been perceived as vulnerable to global sea-level rise, with the potential for mass displacement of exposed populations. The assumption of mass displacement of populations in deltas requires a comprehensive reassessment in the light of present and future migration in deltas, including the potential role of adaptation to influence these decisions. At present, deltas are subject to multiple drivers of environmental change and often have high population densities as they are accessible and productive ecosystems. Climate change, catchment management, subsidence and land cover change drive environmental change across all deltas. Populations in deltas are also highly mobile, with significant urbanization trends and the growth of large cities and mega-cities within or adjacent to deltas across Asia and Africa. Such migration is driven primarily by economic opportunity, yet environmental change in general, and climate change in particular, are likely to play an increasing direct and indirect role in future migration trends. The policy challenges centre on the role of migration within regional adaptation strategies to climate change; the protection of vulnerable populations; and the future of urban settlements within deltas. This paper reviews current knowledge on migration and adaptation to environmental change to discern specific issues pertinent to delta regions. It develops a new integrated methodology to assess present and future migration in deltas using the Volta delta in Ghana, Mahanadi delta in India and Ganges-Brahmaputra-Meghna delta across India and Bangladesh. The integrated method focuses on: biophysical changes and spatial distribution of vulnerability; demographic changes and migration decision-making using multiple methods and data; macro-economic trends and scenarios in the deltas; and the policies and governance structures that constrain and enable adaptation. The analysis is facilitated by a range of

  12. Examining the major contributors and controlling factors of ozone production in a rural area of the Yangtze River Delta region during harvest season

    Directory of Open Access Journals (Sweden)

    X. Pan

    2014-12-01

    Full Text Available Open biomass burning (OBB has been reported to emit substantial amounts of non-methane hydrocarbons (NMHCs, and the mixing of OBB with urban plumes could exacerbate regional ozone (O3 pollution. In the present study, an observational field campaign was performed in a rural area at the edge of Yangtze River Delta region (YRDR during harvest season when intensive open burning of wheat residues was observed. The O3 production rate at the site was calculated using a photochemical box model (Regional Atmospheric Chemical Mechanism, Version 2 constrained by real-time ambient measurements (e.g., O3, volatile organic compounds (VOCs, the sum of NO2 + NO (NOx, J values. During the period impacted by OBB, the O3 concentration frequently exceeded 100 ppbv. Analysis showed that the net O3 production was pronounced, in particular when the site was characterized by a prevailing southerly wind that also brought substantial amounts of NOx emitted from urban areas. At these times, the maximum rate of O3 production was 20 ppbv h−1 with potential production rate of 102 ppbv on a daily basis. The O3 production at the site was typically VOC-sensitive in the morning because NOx dominated the plumes. However, in the afternoon, conditions became NOx-sensitive due to the rapid photochemical consumption of NOx in the production of O3. A positive matrix factorization analysis indicated that solvent usage and OBB were the primary contributors to the mass fraction of ambient NMHCs observed at the study site, and were responsible for 35 and 23% of the total O3 production, respectively. The preferential presence of NOx in the morning inhibited net O3 production; meanwhile O3 built up in the afternoon due to a decrease in NOx concentrations. These results indicated that a joint effort in the regulation of solvent (aromatics usage and OBB, as well as NOx from on-road vehicle exhaust may be effective in eliminating high-O3 pollution risk in the rural areas of the YRDR.

  13. Strategiesfor Developing Senior Tourist Market in the Pearl River Delta Region%珠三角老年旅游市场开发策略

    Institute of Scientific and Technical Information of China (English)

    陈嘉琦; 骆桃桃

    2013-01-01

    Under the background of China's aging society, the travel demand of the aged are increasingly attracting the attention of the so-ciety.Tourism resources in the Pearl River Delta region are abundant;however, the tourism development hasn't met the huge demand with less humanistic product design,single popularity pattern,and unfavorable lodging and catering for the elder people. Tourism product in this region should be designedbased on the characteristics of senior tourists,focusing on health maintenance and reminiscence and preferring to medium and short distance travel with group tours.In addition, the region should constantly enrich the tourism products for the aged,design products specialized for them, provide humanistic service,and complete the distribution and promotion mode, so as to meet the tourism de-mand of the elderly and improve their life quality.%在我国老龄化社会的大背景下,老年人旅游需求越来越需要得到社会的重视。珠三角目的地旅游资源较多,但旅游开发未能满足大量的需求,产品设计不够人性化,宣传方式过于单一,住宿餐饮方面没有考虑到老年人的喜好。珠三角地区应根据老年旅游以养生和怀旧为主,偏好中短途旅游、以团队旅游为主的特征,不断丰富老年旅游产品数量,设计契合老年游客的产品,提供细致的人性化服务,完善分销和促销方式,以满足老年人的旅游需求,提高老年人的生活质量。

  14. Satellite and ground detection of very dense smoke clouds produced on the islands of the Paraná river delta that affected a large region in Central Argentina

    Science.gov (United States)

    Ipiña, A.; Salum, G. M.; Crinó, E.; Piacentini, R. D.

    2012-03-01

    Intense fires were produced on the Paraná river delta islands, Argentina, during most part of 2008, by a combination of an exceptionally dry period and the farmers' use of a fire land-cleaning technique. In April 2008, those fires significantly affected the nearby regions and their inhabitants, from Rosario city to Buenos Aires mega-city. In this work we present satellite as well as ground Aerosol Optical Depth (AOD) at 550 nm data obtained during the propagation of pollution clouds to the central zone of Argentina. The highest value (1.18) was registered at Buenos Aires by atmospheric remote sensing, using the satellite instrument MODIS/Terra on April 18th 2008 at 10:35 local time (= UT - 3 h). On the same day, ground air quality detectors also measured in this city the highest Total Suspended Particle (TSP) value of the month, 2.02 mg/m3. The AOD(550) daily variation at Rosario Astronomical Observatory, which is located near the Paraná riverside, was derived by combining solar ultraviolet erythemal irradiance data (measured with a YES biometre) with model calculations. On April 25th 2008, from 12:00 to 15:30 local time, a rather high and constant AOD(550) value was registered, with a mean value of (0.90 ± 0.21). Cities located on the side of the Rosario-Buenos Aires highway (San Nicolás, Baradero and San Pedro) were also affected, showing a mean AOD(550) between the Rosario and Buenos Aires values. The particulate matter was collected with gridded samplers placed on the Paraná river islands as well as at the Rosario Observatory. They were analysed with a Scanning Electron Microscope (SEM) and mainly showed a biological origin. Even if normally large particles travel small distances from the source, organic aerosol in the range of 40-100 μm and complex asymmetric structures were registered several kilometres away from the aerosol sources on the islands. Another event of intense UV index attenuation (98.6%) occurred on September 18th 2008, due to very dense

  15. Application effects of coated urea and urease and nitrification inhibitors on ammonia and greenhouse gas emissions from a subtropical cotton field of the Mississippi delta region

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Zhou [College of Resources and Environment, Northwest A& F University, Yangling, Shaanxi (China); School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803 (United States); Wang, Jim J., E-mail: jjwang@agcenter.lsu.edu [School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803 (United States); Liu, Shuai [College of Resources and Environment, Northwest A& F University, Yangling, Shaanxi (China); School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803 (United States); Zhang, Zengqiang, E-mail: zqzhang@nwsuaf.edu.cn [College of Resources and Environment, Northwest A& F University, Yangling, Shaanxi (China); Dodla, Syam K.; Myers, Gerald [School of Plant, Environment & Soil Sciences, Louisiana State University Agricultural Center, Baton Rouge, LA 70803 (United States)

    2015-11-15

    Nitrogen (N) fertilization affects both ammonia (NH{sub 3}) and greenhouse gas (GHG) emissions that have implications in air quality and global warming potential. Different cropping systems practice varying N fertilizations. The aim of this study was to investigate the effects of applications of polymer-coated urea and urea treated with N process inhibitors: NBPT [N-(n-butyl)thiophosphoric triamide], urease inhibitor, and DCD [Dicyandiamide], nitrification inhibitor, on NH{sub 3} and GHG emissions from a cotton production system in the Mississippi delta region. A two-year field experiment consisting of five treatments including the Check (unfertilized), urea, polymer-coated urea (ESN), urea + NBPT, and urea + DCD was conducted over 2013 and 2014 in a Cancienne loam (Fine-silty, mixed, superactive, nonacid, hyperthermic Fluvaquentic Epiaquepts). Ammonia and GHG samples were collected using active and passive chamber methods, respectively, and characterized. The results showed that the N loss to the atmosphere following urea-N application was dominated by a significantly higher emission of N{sub 2}O-N than NH{sub 3}-N and the most N{sub 2}O-N and NH{sub 3}-N emissions were during the first 30–50 days. Among different N treatments compared to regular urea, NBPT was the most effective in reducing NH{sub 3}-N volatilization (by 58–63%), whereas DCD the most significant in mitigating N{sub 2}O-N emissions (by 75%). Polymer-coated urea (ESN) and NBPT also significantly reduced N{sub 2}O-N losses (both by 52%) over urea. The emission factors (EFs) for urea, ESN, urea-NBPT, urea + DCD were 1.9%, 1.0%, 0.2%, 0.8% for NH{sub 3}-N, and 8.3%, 3.4%, 3.9%, 1.0% for N{sub 2}O-N, respectively. There were no significant effects of different N treatments on CO{sub 2}-C and CH{sub 4}-C fluxes. Overall both of these N stabilizers and polymer-coated urea could be used as a mitigation strategy for reducing N{sub 2}O emission while urease inhibitor NBPT for reducing NH{sub 3} emission

  16. A conserved cluster of three PRD-class homeobox genes (homeobrain, rx and orthopedia in the Cnidaria and Protostomia

    Directory of Open Access Journals (Sweden)

    Mazza Maureen E

    2010-07-01

    Full Text Available Abstract Background Homeobox genes are a superclass of transcription factors with diverse developmental regulatory functions, which are found in plants, fungi and animals. In animals, several Antennapedia (ANTP-class homeobox genes reside in extremely ancient gene clusters (for example, the Hox, ParaHox, and NKL clusters and the evolution of these clusters has been implicated in the morphological diversification of animal bodyplans. By contrast, similarly ancient gene clusters have not been reported among the other classes of homeobox genes (that is, the LIM, POU, PRD and SIX classes. Results Using a combination of in silico queries and phylogenetic analyses, we found that a cluster of three PRD-class homeobox genes (Homeobrain (hbn, Rax (rx and Orthopedia (otp is present in cnidarians, insects and mollusks (a partial cluster comprising hbn and rx is present in the placozoan Trichoplax adhaerens. We failed to identify this 'HRO' cluster in deuterostomes; in fact, the Homeobrain gene appears to be missing from the chordate genomes we examined, although it is present in hemichordates and echinoderms. To illuminate the ancestral organization and function of this ancient cluster, we mapped the constituent genes against the assembled genome of a model cnidarian, the sea anemone Nematostella vectensis, and characterized their spatiotemporal expression using in situ hybridization. In N. vectensis, these genes reside in a span of 33 kb with the same gene order as previously reported in insects. Comparisons of genomic sequences and expressed sequence tags revealed the presence of alternative transcripts of Nv-otp and two highly unusual protein-coding polymorphisms in the terminal helix of the Nv-rx homeodomain. A population genetic survey revealed the Rx polymorphisms to be widespread in natural populations. During larval development, all three genes are expressed in the ectoderm, in non-overlapping territories along the oral-aboral axis, with distinct

  17. Size distributions of elemental carbon and its contribution to light extinction in urban and rural locations in the pearl river delta region, China

    Directory of Open Access Journals (Sweden)

    H. Yu

    2010-06-01

    Full Text Available Elemental carbon (EC in size-segregated aerosol samples were determined at five urban, one suburban, and one rural locations in the Pearl River Delta region in South China during 2006–2008 period. The size modal characteristics of EC were different at the urban and suburban/rural locations. The urban EC had a dominant condensation mode with a mass median aerodynamic diameter (MMAD in the 0.36–0.43 μm range and a slightly less abundant mode in the droplet mode size (MMAD: 0.8–1.1 μm, while the suburban/rural EC had a prominent mode in the droplet mode size (MMAD: 0.7–1.1 μm and a minor condensation mode (MMAD: 0.22–0.33 μm. Calculations using Mie theory and the measured size distributions of EC, organic carbon, and major inorganic ions indicate that EC-containing particles contributed 76±20% of the observed light extinction at the urban sites. Among the EC-containing particles, EC mass alone contributed 21±11% of the observed light extinction while non-EC materials on the EC particles (i.e., organic matter, ammonium sulfate, and water contributed 55±15%. At the suburban/rural locations, EC-containing particles contributed 37–48% of the measured light extinction, with EC mass contributing 4–10% and non-EC coating materials contributing the remaining light extinction. Our results suggest that EC-containing particles were important to the overall light extinction in the urban atmospheres due to their more abundant presence from vehicular emissions. The EC-containing particles in the suburban/rural locations had a reduced but still significant contribution to light extinction budget.

  18. A two-year study of carbonaceous aerosols in ambient PM2.5 at a regional background site for western Yangtze River Delta, China

    Science.gov (United States)

    Chen, Dong; Cui, Hongfei; Zhao, Yu; Yin, Lina; Lu, Yan; Wang, Qingeng

    2017-01-01

    To analyze the characteristics of regional background carbonaceous aerosols in western Yangtze River Delta (YRD), hourly organic carbon (OC) and elemental carbon (EC) in fine particular matter (PM2.5) were measured with a semi-continuous carbon analyzer at a suburban site in upwind Nanjing from June 2013 to May 2015. Relatively low OC, EC and OC/EC were observed compared to other studies conducted in Nanjing. The reasons include the limited primary emissions around the observation site, the improved emission controls in recent years, and the use of denuder to reduce positive artifact in OC measurement. Resulting from the stable atmosphere conditions and emission variations, the highest concentrations of carbonaceous aerosols were found in both winters, with average OC and EC observed at 11.8 ± 10.0 and 5.9 ± 3.4 μg/m3 for the first one, and 8.1 ± 5 and 4.5 ± 2.4 μg/m3 for the second one, respectively. Compared to 2013, reduced OC and EC were found in summer and autumn 2014, demonstrating the benefits of emission control polices implemented for the Nanjing Youth Olympic, while elevated OC observed in spring 2015 was attributed probably to the increased biomass burning. For the hazy event in winter 2013, the back trajectories of air masses suggested that heavy pollution were from eastern Jiangsu, northern Anhui and Jiangsu, downtown Nanjing, and Shanghai. Secondary aerosol formation played an important role indicated by the larger mass fraction of OC and increased OC/EC in PM2.5 during the heavy pollution period. In the harvest season, biomass burning was estimated to contribute 51% and 16% of OC and EC concentrations, respectively.

  19. The effects of mariculture on heavy metal distribution in sediments and cultured fish around the Pearl River Delta region, south China.

    Science.gov (United States)

    Liang, Peng; Wu, Sheng-Chun; Zhang, Jin; Cao, Yucheng; Yu, Shen; Wong, Ming-Hung

    2016-04-01

    Thirty-six sediment samples were collected from six mariculture sites and corresponding reference sites (approximately 200-300 m away from each mariculture site) to study the effects of mariculture on heavy metal: copper (Cu), zinc (Zn), chromium (Cr) and lead (Pb) distribution in sediments and cultured fish around the Pearl River Delta region, south China. The mean concentrations of Cu, Zn, Cr and Pb in all mariculture sediment samples were 109, 273, 99 and 33 mg/kg, compared with 63, 209, 56 and 23 mg/kg for reference sediment samples, respectively. The Pollution Load Index of sediment for each site was over 1, implying substantial heavy metal pollution. The results of principal component analysis and hierarchical clustering analysis indicate that marine aquaculture activities have enriched the surface sediments underneath mariculture rafts with Cu, Zn and Pb, possibly due to the accumulation of unconsumed fish feeds, fish excreta and antifouling paints (except Cr). Two kinds of fish feeds, feed pellets and trash fish commonly used in Hong Kong were analyzed. The concentrations of Zn and Cu contained in feed pellets were significantly higher (p < 0.05) than in trash fish due to addition of these elements as growth promoters during pellet production. However, the Pb content in trash fish (due to contamination) was significantly higher (p < 0.05) than in feed pellets. Three cultured fish species, namely red snapper (Lutjanus campechanus), orange-spotted grouper (Epinephelus coioides) and snubnose pompano (Trachinotus blochii), were collected from each mariculture site for metal analysis. Lead concentrations in 21 fish samples exceeded the Chinese safety guideline (0.5 mg/kg, GB18406.4-2001), indicating that Pb contamination in cultured fish would be a public health concern.

  20. Use of Traditional and Complementary Medicine as Self-Care Strategies in Community Health Centers: Cross-Sectional Study in Urban Pearl River Delta Region of China.

    Science.gov (United States)

    Chung, Vincent C H; Wong, Samuel Y S; Wang, Harry H X; Wong, Martin C S; Wei, Xiaolin; Wang, Jiaji; Liu, Siya; Ho, Robin S T; Yu, Ellen L M; Griffiths, Sian M

    2016-06-01

    In China, Community Health Centers (CHCs) are major providers of primary care services, but their potential in empowering patients' self-management capacity has not been assessed. This study aims to describe self-care practice patterns amongst CHC attendees in urban China.In this cross-sectional quantitative study, 3360 CHC patients from 6 cities within the Pearl Delta Region were sampled using multistage cluster sampling.Thirty-seven per cent had used with over-the-counter Chinese herbal medicines (OTC CHMs) in the past year and majority of respondents found OTC CHMs effective. OTC CHMs were more popular amongst those who needed to pay out of pocket for CHC services. Less than 10% used vitamins and minerals, and those with a lower socioeconomic background have a higher propensity to consume. Although doubts on their usefulness are expressed, their use by the vulnerable population may reflect barriers to access to conventional health care, cultural affinity, or a defense against negative consequences of illnesses. About 25% performed physical exercise, but the prevalence is lower amongst women and older people. Taiji seems to be an alternative for these populations with promising effectiveness, but overall only 6% of CHC attendees participated.These results suggest that CHCs should start initiatives in fostering appropriate use of OTC CHM, vitamins, and minerals. Engaging community pharmacists in guiding safe and effective use of OTC CHM amongst the uninsured is essential given their low accessibility to CHC services. Prescription of Taiji instead of physical exercises to women and older people could be more culturally appropriate, and the possibility of including this as part of the CHC services worth further exploration.

  1. A climate-based prediction model in the high-risk clusters of the Mekong Delta region, Vietnam: towards improving dengue prevention and control.

    Science.gov (United States)

    Phung, Dung; Talukder, Mohammad Radwanur Rahman; Rutherford, Shannon; Chu, Cordia

    2016-10-01

    To develop a prediction score scheme useful for prevention practitioners and authorities to implement dengue preparedness and controls in the Mekong Delta region (MDR). We applied a spatial scan statistic to identify high-risk dengue clusters in the MDR and used generalised linear-distributed lag models to examine climate-dengue associations using dengue case records and meteorological data from 2003 to 2013. The significant predictors were collapsed into categorical scales, and the β-coefficients of predictors were converted to prediction scores. The score scheme was validated for predicting dengue outbreaks using ROC analysis. The north-eastern MDR was identified as the high-risk cluster. A 1 °C increase in temperature at lag 1-4 and 5-8 weeks increased the dengue risk 11% (95% CI, 9-13) and 7% (95% CI, 6-8), respectively. A 1% rise in humidity increased dengue risk 0.9% (95% CI, 0.2-1.4) at lag 1-4 and 0.8% (95% CI, 0.2-1.4) at lag 5-8 weeks. Similarly, a 1-mm increase in rainfall increased dengue risk 0.1% (95% CI, 0.05-0.16) at lag 1-4 and 0.11% (95% CI, 0.07-0.16) at lag 5-8 weeks. The predicted scores performed with high accuracy in diagnosing the dengue outbreaks (96.3%). This study demonstrates the potential usefulness of a dengue prediction score scheme derived from complex statistical models for high-risk dengue clusters. We recommend a further study to examine the possibility of incorporating such a score scheme into the dengue early warning system in similar climate settings. © 2016 John Wiley & Sons Ltd.

  2. High temperature and risk of hospitalizations, and effect modifying potential of socio-economic conditions: A multi-province study in the tropical Mekong Delta Region.

    Science.gov (United States)

    Phung, Dung; Guo, Yuming; Nguyen, Huong T L; Rutherford, Shannon; Baum, Scott; Chu, Cordia

    2016-01-01

    The Mekong Delta Region (MDR) in Vietnam is highly vulnerable to extreme weather related to climate change. However there have been hardly any studies on temperature-hospitalization relationships. The objectives of this study were to examine temperature-hospitalization relationship and to evaluate the effects of socio-economic factors on the risk of hospitalizations due to high temperature in the MDR. The Generalized Linear and Distributed Lag Models were used to examine hospitalizations for extreme temperature for each of the 13 provinces in the MDR. A random-effects meta-analysis was used to estimate the pooled risk for all causes, and for infectious, cardiovascular, and respiratory diseases sorted by sex and age groups. Random-effects meta-regression was used to evaluate the effect of socio-economic factors on the temperature-hospitalization association. For 1°C increase in average temperature, the risk of hospital admissions increased by 1.3% (95% CI, 0.9-1.8) for all causes, 2.2% (95% CI, 1.4-3.1) for infectious diseases, and 1.1% (95% CI, 0.5-1.7) for respiratory diseases. However the result was inconsistent for cardiovascular diseases. Meta-regression showed population density, poverty rate, and illiteracy rate increased the risk of hospitalization due to high temperature, while higher household income, houses using safe water, and houses using hygienic toilets reduced this risk. In the MDR, high temperatures have a significant impact on hospitalizations for infectious and respiratory diseases. Our findings have important implications for better understanding the future impacts of climate change on residents of the MDR. Adaptation programs that consider the risk and protective factors should be developed to protect residents from extreme temperature conditions.

  3. Change of air quality and its impact on atmospheric visibility in central-western Pearl River Delta.

    Science.gov (United States)

    Wan, Jun-Ming; Lin, Mang; Chan, Chuen-Yu; Zhang, Zhi-Sheng; Engling, Guenter; Wang, Xue-Mei; Chan, Iat-Neng; Li, Shi-Yu

    2011-01-01

    Ambient air quality data, including atmospheric visibility, of Foshan city, a highly polluted city in the Pearl River Delta (PRD), and data obtained by the On-line Air Pollutant Exhaust Monitoring Network (OAPEMN), recently established by the National Emission Monitoring and Control Network for major industrial enterprises, were analyzed and are reported here for the first time, revealing the change in air pollution patterns and its impact on visibility degradation in the last decade. Reduced visibility of less than 8 km (after elimination of rainy and foggy periods) was found 22% of the time from 1998 to 2008, accompanied by elevated levels of pollutants, especially SO₂ and PM₁₀, in comparison with that of other developed cities. However, PM₁₀ showed a steady decreasing trend (0.004 mg m⁻³) year⁻¹) during 2001-2008, in contrast to the noticeable increase in ambient NO₂ concentrations from ~0.020 mg m⁻³ before 2005 to above 0.050 mg m⁻³ afterward. Multiple regression analysis revealed that the percentage of reduced visibility strongly correlated with PM₁₀ concentration, suggesting that visibility degradation was directly proportional to the loading of particles. Moreover, the fairly significant correlation between reduced visibility and NO₂ concentration also implied that the impact of primary emissions of NO₂ and enhanced secondary pollutants, formed via photochemical processes in the atmosphere, could not be ignored. The decreased PM₁₀levels were obviously the predominant factor for the improvement in visibility (5.0% per 0.01 mg m⁻³) and were likely due to the implementation of stricter air pollution control measures for industrial exhaust, which also resulted in reduced SO₂ pollution levels in the recent 2 years. In particular, the OAPEMN records showed an overall enhanced SO₂ removal by 64% in major industrial sectors. The continuous increase in road traffic and lack of efficient NO(x) control strategies in the PRD

  4. Transport of bacteriophage PRD1 through saturated clean sand columns as a function of pH and ionic strength

    Science.gov (United States)

    Sadeghi, G.; Schijven, J. F.; Hassanizadeh, S. M.; Behrends, T.; Gerritse, J.

    2010-12-01

    Groundwater is a major source for drinking water, because of its good microbial quality in its natural state as compared with fresh surface water. Nevertheless, it may be contaminated with pathogenic microorganisms, especially viruses, and that may hamper drinking water production. The two most significant processes controlling virus mobility in the subsurface environment are virus attachment and inactivation. Based on previous studies, many factors have been identified that impact these processes, among them, pH and ionic strength (IS) seem to have the largest influence on virus removal. The objective of this work was to investigate the effects of pH and IS on virus removal in saturated porous media. In addition, it was the objective to determine quantitative relations for these effects. In order to do so, a systematic study was conducted in columns with clean sand under saturated conditions at various pH and IS values within the range of field conditions using bacteriophage PRD1 as a model virus. These experiments were conducted in a 50-cm column with clean quartz sand under saturated conditions and various combinations of pH and ionic strength. Values of pH were 5, 6, 7 and 8 and ionic strength values were 1, 10 and 20 mM. Bacteriophage PRD1 was used as a conservative model virus for virus removal. Attachment, detachment and inactivation rate coefficients were determined from fitting the breakthrough curves. Attachment rate coefficients were found to increase with decreasing pH and increasing ionic strength. Results were used to calculate sticking efficiency values and an empirical formula for it as a function of pH and ionic strength was developed. The applicability of this empirical formula at field scale requires further investigation. Effects of pH and ionic strength on the values of the detachment rate coefficients as well as on inactivation rate coefficients of attached virus particles were also determined but required higher certainty to obtain

  5. Evaluation of a regional chemistry transport model using a newly developed regional OMI NO2 retrieval

    Directory of Open Access Journals (Sweden)

    G. Kuhlmann

    2014-12-01

    Full Text Available In this paper, we evaluate a high-resolution chemistry transport model (CTM (3 km x 3 km spatial resolution with the new Hong Kong (HK NO2 retrieval developed for the Ozone Monitoring Instrument (OMI on-board the Aura satellite. The three-dimensional atmospheric chemistry was modelled in the Pearl River Delta (PRD region in southern China by the Models-3 Community Multiscale Air Quality (CMAQ modelling system from October 2006 to January 2007. In the HK NO2 retrieval, tropospheric air mass factors (AMF were recalculated using high-resolution ancillary parameters of surface reflectance, NO2 profile shapes and aerosol profiles of which the latter two were taken from the CMAQ simulation. We also tested four different aerosol parametrizations. Ground level measurements by the PRD Regional Air Quality Monitoring (RAQM network were used as additional independent measurements. The HK NO2 retrieval increases the NO2 vertical column densities (VCD by (+31 ± 38 %, when compared to NASA's standard product (SP2, and reduces the mean bias (MB between satellite and ground measurements by 26 percentage points from −41 to −15 %. The correlation coefficient r is low for both satellite datasets (r = 0.35 due to the high spatial variability of NO2 concentrations. The correlation between CMAQ and the RAQM network is low (r ≈ 0.3 and the model underestimates the NO2 concentrations in the north-western model domain (Foshan and Guangzhou. We compared the CMAQ NO2 time series of the two main plumes with our regional OMI NO2 product. The model overestimates the NO2 VCDs by about 15 % in Hong Kong and Shenzhen, while the correlation coefficient is satisfactory (r = 0.56. In Foshan and Guangzhou, the correlation is low (r = 0.37 and the model underestimates the VCDs strongly (MB = −40 %. In addition, we estimated that the OMI VCDs are also underestimated by about 10 to 20 % in Foshan and Guangzhou because of the influence of the model parameters on the AMF

  6. Delta III—an evolutionary delta growth

    Science.gov (United States)

    Arvesen, R. J.; Simpson, J. S.

    1996-03-01

    In order to remain competitive in the future and expand the McDonnell Douglas Aerospace market share, MDA has developed an expendable launch system strategy that devices cost-effective launch systems from the Delta II with a growth vehicle configuration called Delta III. The Delta III evolves from the Delta II launch system through development of a larger payload fairing (4-meter diameter), new cryogenically propelled upper stage, new first stage fuel tank, and larger strap-on solid rocket motors. We are developing the Delta III using Integrated Product Development Teams that capitalize on the experience base that has led us to a world record breaking mission success of 49 consecutive Delta II missions. The Delta III first-launch capability is currently planned for the spring of 1998 in support of our first spacecraft customer, Hughes Space and Communications International.

  7. The Niger Delta Avengers, Autonomous Ethnic Clans and Common ...

    African Journals Online (AJOL)

    Nneka Umera-Okeke

    The situation in Niger Delta region has remained an unanswered research question. When oil was discovered .... From the foregone analysis, the greed factor is sufficient to explain the crisis in Niger. Delta given the ..... homeless. The sizeable ...

  8. Detection of formaldehyde emissions from an industrial zone in the Yangtze River Delta region of China using a proton transfer reaction ion-drift chemical ionization mass spectrometer

    Science.gov (United States)

    Ma, Yan; Diao, Yiwei; Zhang, Bingjie; Wang, Weiwei; Ren, Xinrong; Yang, Dongsen; Wang, Ming; Shi, Xiaowen; Zheng, Jun

    2016-12-01

    A proton transfer reaction ion-drift chemical ionization mass spectrometer (PTR-ID-CIMS) equipped with a hydronium (H3+O) ion source was developed and deployed near an industrial zone in the Yangtze River Delta (YRD) region of China in spring 2015 to investigate industry-related emissions of volatile organic compounds (VOCs). Air pollutants including formaldehyde (HCHO), aromatics, and other trace gases (O3 and CO) were simultaneously measured. Humidity effects on the sensitivity of the PTR-ID-CIMS for HCHO detection were investigated and quantified. The performances of the PTR-ID-CIMS were also validated by intercomparing with offline HCHO measurement technique using 2,4-dinitrophenylhydrazone (DNPH) cartridges and the results showed fairly good agreement (slope = 0.81, R2 = 0.80). The PTR-ID-CIMS detection limit of HCHO (10 s, three-duty-cycle averages) was determined to be 0.9-2.4 (RH = 1-81.5 %) parts per billion by volume (ppbv) based on 3 times the standard deviations of the background signals. During the field study, observed HCHO concentrations ranged between 1.8 and 12.8 ppbv with a campaign average of 4.1 ± 1.6 ppbv, which was comparable with previous HCHO observations in other similar locations of China. However, HCHO diurnal profiles showed few features of secondary formation. In addition, time series of both HCHO and aromatic VOCs indicated strong influence from local emissions. Using a multiple linear regression fit model, on average the observed HCHO can be attributed to secondary formation (13.8 %), background level (27.0 %), and industry-related emissions, i.e., combustion sources (43.2 %) and chemical productions (16.0 %). Moreover, within the plumes the industry-related emissions can account for up to 69.2 % of the observed HCHO. This work has provided direct evidence of strong primary emissions of HCHO from industry-related activities. These primary HCHO sources can potentially have a strong impact on local and regional air pollution formation

  9. The upgrade mechanism of China' s traditional manufacturing industry in the region of Yangtze River Delta based on NVC%基于NVC的长三角传统制造业升级机理研究

    Institute of Scientific and Technical Information of China (English)

    钱方明

    2013-01-01

    近年来,长三角制造业低端锁定及其升级路径成为我国制造业发展研究的热点问题之一.我国扩大内需战略的强力实施和消费结构的加快升级,以及长三角一体化进程的加快,为长三角传统制造业通过构建国家价值链实现产业升级提供了难得的历史机遇.本文从价值链视角分析了长三角传统制造业向全球价值链高端升级面临的主要困境,通过构建理论分析模型来考察基于国家价值链的区域传统制造业升级机理,探讨了基于国家价值链的长三角传统制造业升级的主要路径.%In recent years, low - end locking phenomenon of manufacturing industry and its upgrading path in the region of Yangtze River Delta has become one of hot topics in the field of China' s manufacturing industry development research. China' s forceful implementation of boosting domestic demand and accelerating consumption structure upgrade process strategies together with the quickening of regional integration of Yangtze River Delta offer a unique historical opportunity for traditional manufacturing industry in the region of Yangtze River Delta to realize its industrial upgrade through National Value Chain ( NVC) establishment. The main obstacles faced by traditional manufacturing industry in the region of Yangtze River Delta in its upgrading process to high - end activities of global value chain are analyzed from the perspective of value chain. By formulating theoretical analysis model, the upgrade mechanism of regional traditional manufacturing industry is test based on the theory of NVC; the main paths to upgrade traditional manufacturing industry in the region of Yangtze River Delta are also explored.

  10. 珠三角地区区域空气质量实况发布体系建设%Development of Regional Air Quality Live Release System in the Pearl River Delta Region

    Institute of Scientific and Technical Information of China (English)

    岳玎利; 钟流举; 周炎; 区宇波; 袁鸾

    2013-01-01

    在分析国内外空气质量发布情况的基础上,确定了区域空气质量实况发布的内容与形式,并以此为指导优化了区域空气质量监测网络,创立了网络化质量保证与质量控制体系,建立了发布数据的自动化审核方法与工作流程,开发了区域空气质量空间分析优化算法与集成展示技术,设计、研制了区域空气质量实况发布平台,并创新了实况发布体系运行管理机制,顺利实现了珠三角区域空气质量实况发布.同时对我国空气质量信息发布进行了展望.%According to the new standards and with reference to the situation of air quality release at home and abroad,the content and format of the regional air quality live release was confirmed.The regional air quality monitoring network was optimized,the quality assurance and quality control procedures were regulated,the method and work flow of data automatic audit were set up,the spatial analysis algorithm and integrated display of regional air quality were developed,the platform for regional air quality live release was established,and the operation and management mechanisms were created.Therefore,regional air quality live release has realized in the Pearl River Delta region smoothly,which was the first time for the city clusters to live release regional air quality according to the new standards in China.Furthermore,the perspective of air quality release in China was summarized.

  11. The Delta 2 launcher

    Science.gov (United States)

    Ousley, Gilbert W., Sr.

    1991-12-01

    The utilization of the Delta 2 as the vehicle for launching Aristoteles into its near Sun synchronous orbit is addressed. Delta is NASA's most reliable launch vehicle and is well suited for placing the present Aristoteles spacecraft into a 400 m circular orbit. A summary of some of the Delta 2 flight parameters is presented. Diagrams of a typical Delta 2 two stage separation are included along with statistics on delta reliability and launch plans.

  12. Charged current weak electroproduction of $\\Delta$ resonance

    CERN Document Server

    Alvarez-Ruso, L; Vacas, M J V

    1998-01-01

    We study the weak production of $\\Delta$ (i.e. $e^{-} + p \\to \\Delta^{0}+ energy range corresponding to the Mainz and TJNAF electron accelerators. The differential cross sections $\\sigma(\\theta)$ are found to be of the order of $ 10^{-39}$ cm$^2$/sr, over a range of angles which increases with energy. The possibility of observing these reactions with the high luminosities available at these accelerators, and studying the weak N-$\\Delta$ transition form factors through these reactions is discussed. The production cross section of N$^*(1440)$ in the kinematic region of $\\Delta$ production is also estimated and found to be small.

  13. 基于陆路交通网的长江三角洲区域可达性评价%Regional accessibility of land traffic network in the Yangtze River Delta

    Institute of Scientific and Technical Information of China (English)

    张莉; 陆玉麒

    2007-01-01

    In a given district, the accessibility of any point should be the synthetically evaluation of the internal and external accessibilities. Using MapX component and Delphi, the author presents an information system to calculate and analyze regional accessibility according to the shortest travel time, generating thus a mark diffusing figure. Based on land traffic network, this paper assesses the present and the future regional accessibilities of sixteen major cities in the Yangtze River Delta. The result shows that the regional accessibility of the Yangtze River Delta presents a fan with Shanghai as its core. The top two most accessible cities are Shanghai and Jiaxing, and the bottom two ones are Taizhou (Zhejiang province) and Nantong. With the construction of Sutong Bridge, Hangzhouwan Bridge and Zhoushan Bridge, the regional internal accessibility of all cities will be improved. Especially for Shaoxing, Ningbo and Taizhou (Jiangsu province), the regional internal accessibility will be decreased by one hour, and other cities will be shortened by about 25 minutes averagely. As the construction of Yangkou Harbor in Nantong, the regional external accessibility of the harbor cities in Jiangsu province will be speeded up by about one hour.

  14. Observation studies on the influence of atmospheric boundary layer characteristics associate with air quality in dry season over the Pearl River Delta, China

    Science.gov (United States)

    Fan, Shaojia; Wu, Meng; Li, Haowen; Liao, Zhiheng; Fan, Qi; Zhu, Wei

    2016-04-01

    The characteristics of atmospheric boundary layer (ABL) is the very important factors influence on air quality in dry season over the Pearl River Delta (PRD), China. Based on the sounding data at six stations (Xinken,Dongguan, Sanshui, Nanhai, Shunde, and Heshan) which obtained from three times ABL experiments carried in dry season over PRD, the influence of wind and temperature vertical structure to the air quality over PRD has been studied with wind and temperature profiles, inversion layer, recirculation factor (RF), atmospheric boundary layer height (ABLH) and ventilation index (VI). It was found that the vertical wind of PRD could be divided in typical three layers according two wind shears appeared in 800 m and 1300 m. The thickness of calm or lower wind speed layer in pollution days was 500-1000m thicker than that of clean days, and its last time also much longer than that of clean days. The frequency of surface inversion in pollution days was about 35%,the mean thickness was about 100 m. With the influence of sea breeze, the frequency and thickness of surface inversion layer at Xinken station was a little lower than that in inland. Influenced by sea-land breezes and urban heat-island circulation, the RF of pollution days in coastal and urban area was quite smaller than that of clean days. During sea-land breezes days, the pollutants would be transported back to inland in nighttime with the influence of sea breeze, and resulted in 72.7% sea-land breezes was pollution days. The evolution of ABL was very typical in PRD during dry season. In pollution days, daily ABLH in PRD was lower than 500 m, daily VI was about 500-1500 m2/s. In clean days, daily VI was much larger than 2500 m2/s. An improved conceptual model of ABL influence on poor air quality and the parameters of the ABL characteristics associate with poor air quality in dry season over PRD had been summarized.

  15. Delta Blues Scholarship and Imperialist Nostalgia.

    Science.gov (United States)

    Nye, William P.

    When Delta blues are considered to be "folk music," the genre is inextricably tied to the neocolonial, sharecropping system of cotton production characteristic of the Mississippi Delta region between the Civil War and World War II. "Imperialist nostalgia," then, arises in accounts which pay primary and positive tribute to blues…

  16. Investigation on bacterial community and diversity in the multilayer aquifer-aquitard system of the Pearl River Delta, China.

    Science.gov (United States)

    Liu, Kun; Jiao, Jiu Jimmy; Gu, Ji-Dong

    2014-12-01

    Bacteria play an important role in groundwater chemistry. The groundwater resource in the Pearl River Delta (PRD) is responsible for 50 million people's water requirement. High amount of ammonium, arsenic and methane had been reported in groundwater of the PRD, which was considered as the result of intensive bacterial metabolism in the multilayer aquifer-aquitard system. To investigate bacterial community in this system and its relation with groundwater chemistry, sediment and groundwater samples were taken from representative locations in the PRD at different lithological units. Bacterial 16S rRNA gene clone libraries were constructed for microbial identifications and community structures in different strata. Canonical correlation analysis between bacterial linages and environment variables (Cl(-), PO4(3-), SO4(2-), NH4(+)) showed that community structures were significantly modified by geological conditions. Higher bacterial diversity was observed in samples from the Holocene aquitard M1 and aquifer T1, while in the older aquitard M2 and basal aquifer T2, bacterial diversity was much lower. Chloroflexi, γ-proteobacteria and δ-proteobacteria were the dominant phyla in the aquitard sediment. β-proteobacteria was the dominant phylum in sediment which was strongly influenced by fresh water. The results of this study demonstrated that bacterial community contains information of geological events such as sea transgression and deltaic evolution, and microbes in the aquitards have great potential in dominating groundwater quality in aquifers.

  17. Implications of crude oil pollution on natural regeneration of plant spe-cies in an oil-producing community in the Niger Delta Region of Nigeria

    Institute of Scientific and Technical Information of China (English)

    U.D Chima; G. Vure

    2014-01-01

    The study evaluated the impact of crude oil pollution on natu-ral regeneration of plant species in a major oil-producing community in the Niger Delta region of Nigeria. Three sites-unpolluted site (US), polluted and untreated site (PUS), and polluted and treated site (PTS)-were purposively chosen for the study. The seedling emergence method was used to evaluate soil seed banks in the various sites at two depths, 0 to 10 cm and 10 to 20 cm. Woody-plant species richness, abundance, and diversity were higher in the US seed bank than in the PUS and PTS seed banks. The highest number of non-woody plants was observed in the US, followed by the PTS, and then the PUS. Both species richness and diversity of non-woody plants were highest at the US, followed by the PUS, and lowest in the PTS. Woody species in the US seed bank were 87.5% and 80% dissimilar with those of the PUS and PTS at 0-10 cm and 10-20 cm respectively. No variation was observed between woody species in the PUS and PTS seed banks. Non-woody species at 0-10 cm US seed bank were 73.08% dissimilar with those of PUS at the two soil depths and 81.48/88.46%dissimilar with those of the 0-10/10-20 cm of the PTS respectively. At 10-20 cm, non-woody species of the US were 69.66% dissimilar with those from each of the two soil depths in PUS;and 73.91/81.82% dissimilar with those of 0-10/10-20 cm of the PTS respectively. Non-woody species variation between the PUS and PTS was higher at 10-20 cm than 0-10 cm. The poor seed bank attributes at the polluted sites demonstrates that crude oil pollution negatively af-fected the natural regeneration potential of the native flora because soil seed banks serve as the building blocks for plant succession. Thorough remediation and enrichment planting are recommended to support the recovery process of vegetation in the polluted areas.

  18. Two Component Decomposition of Dual Polarimetric HH/VV SAR Data: Case Study for the Tundra Environment of the Mackenzie Delta Region, Canada

    Directory of Open Access Journals (Sweden)

    Tobias Ullmann

    2016-12-01

    Full Text Available This study investigates a two component decomposition technique for HH/VV-polarized PolSAR (Polarimetric Synthetic Aperture Radar data. The approach is a straight forward adaption of the Yamaguchi decomposition and decomposes the data into two scattering contributions: surface and double bounce under the assumption of a negligible vegetation scattering component in Tundra environments. The dependencies between the features of this two and the classical three component Yamaguchi decomposition were investigated for Radarsat-2 (quad and TerraSAR-X (HH/VV data for the Mackenzie Delta Region, Canada. In situ data on land cover were used to derive the scattering characteristics and to analyze the correlation among the PolSAR features. The double bounce and surface scattering features of the two and three component scattering model (derived from pseudo-HH/VV- and quad-polarized data showed similar scattering characteristics and positively correlated-R2 values of 0.60 (double bounce and 0.88 (surface scattering were observed. The presence of volume scattering led to differences between the features and these were minimized for land cover classes of low vegetation height that showed little volume scattering contribution. In terms of separability, the quad-polarized Radarsat-2 data offered the best separation of the examined tundra land cover types and will be best suited for the classification. This is anticipated as it represents the largest feature space of all tested ones. However; the classes “wetland” and “bare ground” showed clear positions in the feature spaces of the C- and X-Band HH/VV-polarized data and an accurate classification of these land cover types is promising. Among the possible dual-polarization modes of Radarsat-2 the HH/VV was found to be the favorable mode for the characterization of the aforementioned tundra land cover classes due to the coherent acquisition and the preserved co-pol. phase. Contrary, HH/HV-polarized and VV

  19. Satellite-derived high resolution PM2.5 concentrations in Yangtze River Delta Region of China using improved linear mixed effects model

    Science.gov (United States)

    Ma, Zongwei; Liu, Yang; Zhao, Qiuyue; Liu, Miaomiao; Zhou, Yuanchun; Bi, Jun

    2016-05-01

    Satellite remotely sensed aerosol optical depth (AOD) provides an effective way to fill the spatial and temporal gaps left by ground PM2.5 monitoring network. Previous studies have established robust advanced statistical models to estimate PM2.5 using AOD data in China. However, their coarse resolutions (˜10 km or greater) of PM2.5 estimations are not enough to support the health effect studies at urban scales. In this study, 3 km AOD data from Moderate Resolution Imaging Spectroradiometer (MODIS) collection 6 products were used to estimate the high resolution PM2.5 concentrations in Yangtze Delta Region of China. We proposed a nested linear mixed effects (LME) model including nested month-, week-, and day-specific random effects of PM2.5-AOD relationships. Validation results show that the LME model only with day-specific random effects (non-nested model) used in previous studies has poor performance in the days without PM2.5-AOD matchups (the R2 of day-of-year-based cross validation (DOY-based CV) is 0.148). The results also show that our nested model cannot improve the performance of non-nested model in the days with PM2.5-AOD matchups (sample-based CV R2 = 0.671 for nested model vs. 0.661 for non-nested model), but can greatly improve the model performance beyond those days (DOY-based CV R2 = 0.339 for nested model vs. 0.148 for non-nested model). To further improve the model performance, we applied the "buffer models" (i.e., models fitted from datasets which ground PM2.5 were matched with the average AOD values within certain radius buffer zones of gridded PM2.5 data) on the 3 km AOD data since the "buffer models" has more days with PM2.5-AOD matchups and can provide more day-specific relationships. The results of this study show that 3 km MODIS C6 AOD data can be used to estimate PM2.5 concentrations and can provide more detailed spatial information for urban scale studies. The application of our nested LME model can greatly improve the accuracy of 3 km PM2

  20. Observations and Impacts of Permafrost Thaw in the Lower Yukon River Basin and Yukon Delta Region: the Importance of Local Knowledge

    Science.gov (United States)

    Herman-Mercer, N. M.; Elder, K.; Toohey, R.; Mutter, E. A.

    2015-12-01

    In regions of the arctic and subarctic baseline measurements of permafrost dynamics are lacking and scientific research can be especially expensive when remote sensing techniques are utilized. This research demonstrated the importance of local observations, a powerful tool for understanding landscape change, such as permafrost dynamics. Fifty-five interviews were recently conducted with community members in four villages of the lower Yukon River Basin and Yukon Delta to understand local environmental and landscape changes and the impacts these changes may be having on the lives and livelihoods of these communities. The interviews were semi-structured and focused on many climate and landscape change factors including knowledge of permafrost in their community or the surrounding landscape. All positive respondents stated that they believe the permafrost is thawing. The research revealed that residents of the arctic and subarctic interact with permafrost in a variety of ways. Some people utilize permafrost to store food resources and have found that they have to dig deeper presently than in their youth in order to find ground cold enough. Others are involved in digging graves and report encountering easier excavation in recent years. Subsistence hunters and gatherers travel long distances by snowmobile and boat, and have noticed slumping ground, eroding river banks and coast lines, as well as land that seems to be rising. Finally, all residents of the arctic and subarctic interact with permafrost in terms of the stability of their homes and other infrastructure. Many interview participants complained of their houses leaning and needing more frequent adjustment than in the past. Indigenous residents of the arctic and subarctic have intimate relationships with their landscape owing to their subsistence lifestyle and are also connected to the landscape of the past through the teachings of their elders. Further, arctic and subarctic communities will sustain the majority

  1. Spatio-temporal patterns and predictions of phytoplankton assemblages in a subtropical river delta system

    DEFF Research Database (Denmark)

    Wang, Chao; Li, Xinhui; Wang, Xiangxiu;

    2016-01-01

    similarities. These groups were distinct with respect to species richness, biomass and indicators, especially for groups representing spatial dimension. The Linear Discriminant Analysis (LDA) model indicated that the spatial patterns of phytoplankton assemblages were mostly explained by water quality variables...... dominate? Are physical or chemical factors determining the above patterns in this area? We conclude that the spatial-temporal patterns of phytoplankton in the PRD are closely associated with eutrophication levels caused by anthropogenic activities. The spatial patterns are apparently dominant in this area......Spatial and seasonal sampling within a subtropical river delta system, the Pearl River Delta (China), provided data to determine seasonal phytoplankton patterns and develop prediction models. The high nutrient levels and frequent water exchanges resulted in a phytoplankton community with greatest...

  2. Nonpolar organic compounds as PM2.5 source tracers: Investigation of their sources and degradation in the Pearl River Delta, China

    Science.gov (United States)

    Wang, Qiongqiong; Feng, Yongming; Huang, X. H. Hilda; Griffith, Stephen M.; Zhang, Ting; Zhang, Qingyan; Wu, Dui; Yu, Jian Zhen

    2016-10-01

    A group of nonpolar organic compounds (NPOCs) in five compound classes including alkanes, polycyclic aromatic hydrocarbons (PAHs), hopanes, steranes, and 1,3,5-triphenylbenzene were quantified in samples of particulate matter of aerodynamic diameter less than 2.5 μm collected at four sites in the Pearl River Delta (PRD) region, China, over a 2 year period from 2011 to 2012. The four sites include industrial (Nanhai), urban (Guangzhou), urban outskirt (Dongguan), and suburban (Nansha) locations. Some NPOCs are uniquely emitted from particular combustion sources and thereby serving as markers in source apportionment. Based on this multiyear and multisite NPOC data set, spatial and seasonal variations, correlation analysis, and ratio-ratio plots were used to investigate the source information and degradation of NPOC tracers. In summer, NPOCs showed distinct local emission characteristics, with urban sites having much higher concentrations than suburban sites. In winter, regional transport was an important influence on NPOC levels, driving up concentrations at all sampling sites and diminishing an urban-suburban spatial gradient. The lighter NPOCs exhibited more prominent seasonal variations. Such spatiotemporal features suggest that their particle-phase abundance is more influenced by temperature, which is a critical factor in controlling the extent of semivolatile organics partitioned into the aerosol phase. The heavier NPOCs, especially PAHs, showed negligible correlation among the four sites, suggesting more influence from local emissions. Ratio-ratio plots indicate photodegradation and mixing of various sources for the NPOCs in the PRD. A positive matrix factorization (PMF) analysis of this large NPOC data set suggests that heavier NPOCs are more suitable source indicators than lighter NPOCs. Incorporating particle-phase light NPOC concentrations in PMF produces a separate factor, which primarily contains those light NPOCs and likely is not a source factor. Total

  3. 长三角区域环境空气质量预测预警体系建设的思考%Discussions on the System of Regional Air Quality Forecasting and Early Warning in Yangtze Delta Area

    Institute of Scientific and Technical Information of China (English)

    刘娟

    2012-01-01

    Environmental information sharing system and air quality monitoring network of the Yangtze River Delta Region for Shanghai Exuv 2010 provide a successful case for long-tenr regional air quality forecasting anDelta were analysed. It is concluded thai Ihe full range of air quality monitoring network and data sharing, emissiun uivenlurj establishment, multi-Diodel ensemble forecast system development, regional consultation and personnel training system are main factors for the long-term project and play an important role in establishment of Yangtze Delta Regional Air Quality Early Forecast Warning System.%世博会期间长三角区域空气质量自动监测网络和数据共享平台的成功搭建和有效运行,为探索长三角区域空气质量预测预警长期合作模式提供了宝贵的经验和启示.需要建立全方位区域空气质量监测网络和数据资源共享系统、源排放清单、开发区域多模式集合预报系统,构建区域多层面运作机制和会商制度,建设一批专业技术和复合型人才队伍.区域不同层面有效的管理体制机制的保障是区域环境空气质量预测预警体系的基础支撑.

  4. Simulating dynamics of (delta){sup 13}C of CO{sub 2} in the planetary boundary layer a boreal forest region: covariation between surface fluxes and atmospheric mixing

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Baozhang; Chen, Jing M. [Univ. of Toronto, ON (Canada). Dept. of Geography; Tans, Pieter P. [National Oceanic and Atmospheric Administration, Boulder, CO (United States). Earth System Research Lab.; Huang, Lin [Environment Canada, Toronto, ON (Canada). Atmospheric Science and Technology Directorate

    2006-11-15

    Stable isotopes of CO{sub 2} contain unique information on the biological and physical processes that exchange CO{sub 2} between terrestrial ecosystems and the atmosphere. Ecosystem exchange of carbon isotopes with the atmosphere is correlated diurnally and seasonally with the planetary boundary layer (PBL) dynamics. The strength of this kind of covariation affects the vertical gradient of (delta){sup 13}C and thus the global (delta){sup 13}C distribution pattern. We need to understand the various processes involved in transport/diffusion of carbon isotope ratio in the PBL and between the PBL and the biosphere and the troposphere. In this study, we employ a one-dimensional vertical diffusion/transport atmospheric model (VDS), coupled to an ecosystem isotope model (BEPS-EASS) to simulate dynamics of {sup 13}CO{sub 2} in the PBL over a boreal forest region in the vicinity of the Fraserdale (FRD) tower (49 deg 52 min 29.9 sec N, 81 deg 34 min 12.3 sec W) in northern Ontario, Canada. The data from intensive campaigns during the growing season in 1999 at this site are used for model validation in the surface layer. The model performance, overall, is satisfactory in simulating the measured data over the whole course of the growing season. We examine the interaction of the biosphere and the atmosphere through the PBL with respect to (delta){sup 13}C on diurnal and seasonal scales. The simulated annual mean vertical gradient of (delta){sup 13}C in the PBL in the vicinity of the FRD tower was about 0.025% in 1999. The (delta){sup 13}C vertical gradient exhibited strong diurnal (29%) and seasonal (71%) variations that do not exactly mimic those of CO{sub 2}. Most of the vertical gradient (96.5% {+-}) resulted from covariation between ecosystem exchange of carbon isotopes and the PBL dynamics, while the rest (3.5%{+-}) was contributed by isotopic disequilibrium between respiration and photosynthesis. This disequilibrium effect on (delta){sup 13}C of CO{sub 2} dynamics in PBL

  5. Simulating dynamics of {delta}{sup 13}C of CO{sub 2} in the planetary boundary layer a boreal forest region: covariation between surface fluxes and atmospheric mixing

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Baozhang; Chen, Jing M. [Univ. of Toronto, ON (Canada). Dept. of Geography; Tans, Pieter P. [National Oceanic and Atmospheric Administration, Boulder, CO (United States). Earth System Research Lab.; Huang, Lin [Environment Canada, Toronto, ON (Canada). Atmospheric Science and Technology Directorate

    2006-11-15

    Stable isotopes of CO{sub 2} contain unique information on the biological and physical processes that exchange CO{sub 2} between terrestrial ecosystems and the atmosphere. Ecosystem exchange of carbon isotopes with the atmosphere is correlated diurnally and seasonally with the planetary boundary layer (PBL) dynamics. The strength of this kind of covariation affects the vertical gradient of {delta}{sup 13}C and thus the global {delta}{sup 13}C distribution pattern. We need to understand the various processes involved in transport/diffusion of carbon isotope ratio in the PBL and between the PBL and the biosphere and the troposphere. In this study, we employ a one-dimensional vertical diffusion/transport atmospheric model (VDS), coupled to an ecosystem isotope model (BEPS-EASS) to simulate dynamics of {sup 13}CO{sub 2} in the PBL over a boreal forest region in the vicinity of the Fraserdale (FRD) tower (49 deg 52 min 29.9 sec N, 81 deg 34 min 12.3 sec W) in northern Ontario, Canada. The data from intensive campaigns during the growing season in 1999 at this site are used for model validation in the surface layer. The model performance, overall, is satisfactory in simulating the measured data over the whole course of the growing season. We examine the interaction of the biosphere and the atmosphere through the PBL with respect to {delta}{sup 13}C on diurnal and seasonal scales. The simulated annual mean vertical gradient of {delta}{sup 13}C in the PBL in the vicinity of the FRD tower was about 0.025% in 1999. The {delta}{sup 13}C vertical gradient exhibited strong diurnal (29%) and seasonal (71%) variations that do not exactly mimic those of CO{sub 2}. Most of the vertical gradient (96.5% {+-}) resulted from covariation between ecosystem exchange of carbon isotopes and the PBL dynamics, while the rest (3.5%{+-}) was contributed by isotopic disequilibrium between respiration and photosynthesis. This disequilibrium effect on {delta}{sup 13}C of CO{sub 2} dynamics in PBL

  6. Delta Plaza kohvik = Delta Plaza cafe

    Index Scriptorium Estoniae

    2010-01-01

    Tallinnas Pärnu mnt 141 asuva kohviku Delta Plaza sisekujundusest. Sisearhitektid Tiiu Truus ja Marja Viltrop (Stuudio Truus OÜ). Tiiu Truusi tähtsamate tööde loetelu. Büroohoone Delta Plaza arhitektid Marika Lõoke ja Jüri Okas (AB J. Okas & M. Lõoke)

  7. Delta Plaza kohvik = Delta Plaza cafe

    Index Scriptorium Estoniae

    2010-01-01

    Tallinnas Pärnu mnt 141 asuva kohviku Delta Plaza sisekujundusest. Sisearhitektid Tiiu Truus ja Marja Viltrop (Stuudio Truus OÜ). Tiiu Truusi tähtsamate tööde loetelu. Büroohoone Delta Plaza arhitektid Marika Lõoke ja Jüri Okas (AB J. Okas & M. Lõoke)

  8. Process analysis of regional ozone formation over the Yangtze River Delta, China using the Community Multi-scale Air Quality modeling system

    Directory of Open Access Journals (Sweden)

    L. Li

    2012-06-01

    Full Text Available High ozone concentration has become an important issue in summer in most economically developed cities in Eastern China. In this paper, observations at an urban site within the Shanghai city are used to examine the typical high ozone episodes in August 2010, and the MM5-CMAQ modeling system is then applied to reproduce the typical high ozone episodes. In order to account for the contribution of different atmospheric processes during the high pollution episodes, the CMAQ integrated process rate (IPR is used to assess the different atmospheric dynamics in rural and urban sites of Shanghai, Nanjing and Hangzhou, which are typical cities of the Yangtze River Delta (YRD region. In order to study the contributions of the main atmospheric processes leading to ozone formation, vertical process analysis in layer 1 (0–40 m, layer 7 (350–500 m, layer 8 (500–900 m and layer 10 (1400–2000 m has been considered. The observations compare well with the results of the numerical model. IPR analysis shows that the maximum concentration of ozone occurs due to transport phenomena, including vertical diffusion and horizontal advective transport. The gas-phase chemistry producing O3 mainly occurs in the height of 300–1500 m, causing a strong vertical O3 transport from upper levels to the surface layer. The gas-phase chemistry is an important sink for O3 in the surface layer, coupled with dry deposition. The cloud processes, horizontal diffusion and heterogeneous chemistry contributions are negligible during the whole episode. In the urban Shanghai area, the average O3 production rates contributed by vertical diffusion and horizontal transport are 24.7 ppb h−1, 3.6 ppb h−1, accounting for 27.6% and 6.6% of net surface O3 change, respectively. The average contributions of chemistry, dry deposition and vertical advective transport to O3 production are −21.9, −4.3 and

  9. PM{sub 2.5} acidity at a background site in the Pearl River Delta region in fall-winter of 2007–2012

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Xiaoxin [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (China); Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong (China); Shenzhen Research Institute, Hong Kong Polytechnic University (China); Guo, Hai, E-mail: ceguohai@polyu.edu.hk [Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Hong Kong (China); Shenzhen Research Institute, Hong Kong Polytechnic University (China); Wang, Xinming, E-mail: wangxm@gig.ac.cn [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (China); Ding, Xiang; He, Quanfu; Liu, Tengyu; Zhang, Zhou [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences (China)

    2015-04-09

    Highlights: • 24-h PM{sub 2.5} samples were collected in fall-winter of 2007–2012. • The annual reduction trends of [H{sup +}]{sub total} and [H{sup +}]{sub in-situ} of PM{sub 2.5} was −32 ± 1.5 and −9 ± 1.7 nmol m{sup −3}, respectively. • On hazy days, the concentration of OM showed significant enhancement when [H{sup +}]{sub in-situ} ranged from 85 to 240 nmol m{sup −3}. • [H{sup +}]{sub in-situ} presented a close relationship with NO{sub 3}{sup −} formation mechanisms in low and high acidity of PM{sub 2.5}. - Abstract: Based on field observations and thermodynamic model simulation, the annual trend of PM{sub 2.5} acidity and its characteristics on non-hazy and hazy days in fall-winter of 2007–2012 in the Pearl River Delta region were investigated. Total acidity ([H{sup +}]{sub total}) and in-situ acidity ([H{sup +}]{sub in-situ}) of PM{sub 2.5} significantly decreased (F-test, p < 0.05) at a rate of −32 ± 1.5 nmol m{sup −3} year{sup −1} and −9 ± 1.7 nmol m{sup −3} year{sup −1}, respectively. The variation of acidity was mainly caused by the change of the PM{sub 2.5} component, i.e., the decreasing rates of [H{sup +}]{sub total} and [H{sup +}]{sub in-situ} due to the decrease of sulfate (SO{sub 4}{sup 2−}) exceeded the increasing rate caused by the growth of nitrate (NO{sub 3}{sup −}). [H{sup +}]{sub total}, [H{sup +}]{sub in-situ} and liquid water content on hazy days were 0.9–2.2, 1.2–3.5 and 2.0–3.0 times those on non-hazy days, respectively. On hazy days, the concentration of organic matter (OM) showed significant enhancement when [H{sup +}]{sub in-situ} increased (t-test, p < 0.05), while this was not observed on non-hazy days. Moreover, when the acidity was low (i.e., R = [NH{sub 4}{sup +}]/(2 × [SO{sub 4}{sup 2−}] + [NO{sub 3}{sup −}]) > 0.6), NH{sub 4}NO{sub 3} was most likely formed via homogenous reaction. When the acidity was high (R ≤ 0.6), the gas-phase formation of NH{sub 4}NO{sub 3} was

  10. 长三角区域社会化信息协同共享模式研究%A Collaborative Sharing Model of Socialized Information in Yangtze River Delta Region

    Institute of Scientific and Technical Information of China (English)

    蒋定福; 岳焱

    2012-01-01

    In order to enhance the efficiency of e-government performance and to promote the construction of service-oriented government,a research on collaborative sharing model of socialized information in Yangtze River Delta Region is carried out from a collaborative perspective.This paper firstly proposed the collaborative sharing model of information based on the actuality that the government socialized information sharing is realized in Yangtze River Delta Region.Then the structure of the information collaborative sharing system is discussed.Finally,the collaborative sharing model of socialized information is studied from three perspectives: government unit,inter-government,and pure public information in Yangtze River Delta Region.%为了提升电子政务效能及推动服务型政府建设,采用协同思想对长三角区域社会化信息资源共享进行研究。文章从长三角区域间政府社会化信息共享的现实条件入手,构建信息协同共享模型,对长三角区域社会化信息协同共享体系结构进行了探讨,并从长三角区域各政府单元内、长三角区域政府间、长三角纯公共信息三个层面研究其信息协同共享模式。

  11. Impact of sea-level rise in a Mediteranean delta: The Ebro delta cast

    NARCIS (Netherlands)

    Sánchez-Arcilla, A.; Stive, M.D.F.; Jiménez, J.A.; García, M.A.

    1993-01-01

    In anticipation of a comprehensive, multidisciplinary study on the impact of climatic change on the Ebro Delta preliminary results are here presented of the response of the outer delta coast to present and future relative sea-level rise. Due to the absence of observations and predictions of regional

  12. Impact of sea-level rise in a Mediteranean delta: The Ebro delta cast

    NARCIS (Netherlands)

    Sánchez-Arcilla, A.; Stive, M.D.F.; Jiménez, J.A.; García, M.A.

    1993-01-01

    In anticipation of a comprehensive, multidisciplinary study on the impact of climatic change on the Ebro Delta preliminary results are here presented of the response of the outer delta coast to present and future relative sea-level rise. Due to the absence of observations and predictions of regional

  13. Study of polarized-e polarized-p --> e-prime p pi0 in the Delta(1232) mass region using polarization asymmetries

    CERN Document Server

    Biselli, A; Amaryan, M J; Anciant, E; Anghinolfi, M; Asavapibhop, B; Asryan, G; Audit, G; Auger, T; Avakian, H; Barrow, S; Battaglieri, M; Beard, K; Bektasoglu, M; Bertozzi, W; Bianchi, N; Boiarinov, S; Bonner, B E; Bosted, P; Bouchigny, S; Bradford, R; Branford, D; Brooks, W K; Bültmann, S; Burkert, V D; Calarco, J R; Carman, D S; Carnahan, B; Cetina, C; Ciciani, L; Cole, P L; Coleman, A; Connelly, J; Cords, D; Corvisiero, P; Crabb, D; Crannell, H; Cummings, J; De Sanctis, E; De Vita, R; Degtyarenko, P V; Demirchyan, R A; Denizli, H; Dennis, L C; Dharmawardane, K V; Dhuga, K S; Djalali, C; Dodge, G E; Domingo, John J; Doughty, D C; Dragovitsch, P; Dugger, M; Dytman, S; Eckhause, M; Efremenko, Yu V; Egiyan, H; Egiyan, K S; Elouadrhiri, L; Empl, A; Eugenio, P; Farhi, L; Fatemi, R; Feuerbach, R J; Ficenec, J; Fissum, K; Forest, T A; Freyberger, A P; Frolov, V; Funsten, H; Gaff, S J; Gai, M; Gavalian, G; Gavrilov, V B; Gilad, S; Gilfoyle, G P; Giovanetti, K L; Girard, P; Golovatch, E; Griffioen, K A; Guidal, M; Guillo, M R; Guo, L; Gyurjyan, V; Hancock, D; Hardie, J; Heddle, D; Hersman, F W; Hicks, K; Hicks, R S; Holtrop, M; Hu, J; Hyde-Wright, C E; Ito, M M; Jenkins, D; Joo, K; Kelley, J H; Khandaker, M; Kim, K Y; Kim, K; Kim, W; Klein, A; Klein, F J; Klimenko, A V; Klusman, M; Kossov, M; Kramer, L H; Kuang, Y; Kühn, J; Kuhn, S E; Lachniet, J; Laget, J M; Lawrence, D; Leksin, G A; Longhi, A; Loukachine, K; Major, R W; Manak, J J; Marchand, C; Matthews, S K; McAleer, S; McNabb, J W C; McCarthy, J; Mecking, B A; Mestayer, M D; Meyer, C A; Minehart, R C; Mirazita, M; Miskimen, R; Mokeev, V; Muccifora, V; Müller, J; Murphy, L Y; Mutchler, G S; Napolitano, J; Nelson, S O; Niculescu, G; Niczyporuk, B B; Niyazov, R A; Nozar, M; O'Brien, J T; O'Rielly, G V; Ohandjanyan, M S; Osipenko, M; Park, K; Patois, Y; Peterson, G A; Philips, S; Pivnyuk, N; Pocanic, D; Pogorelko, O I; Polli, E; Preedom, B M; Price, J W; Qin, L M; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ritchie, B G; Rock, S E; Ronchetti, F; Rossi, P; Rowntree, D; Rubin, P D; Sabourov, K; Salgado, C W; Sapunenko, V; Sargsyan, M; Schumacher, R A; Serov, V S; Sharabyan, Yu G; Shaw, J; Shuvalov, S M; Simionatto, S; Skabelin, A V; Smith, E S; Smith, L C; Smith, T; Sober, D I; Sorrell, L; Spraker, M; Stepanyan, S; Stoler, P; Strakovsky, I I; Taiuti, M; Taylor, S; Tedeschi, D J; Thoma, U; Thompson, R; Todor, L; Tung, T Y; Tur, C; Ungaro, M; Vineyard, M F; Vlassov, A; Wang, K; Weinstein, L B; Weller, H; Welsh, R; Weygand, D P; Whisnant, S; Witkowski, M; Wolin, E; Yegneswaran, A; Yun, J; Zhang, B; Zhao, J; Zhou, Z

    2003-01-01

    Measurements of the angular distributions of target and double spin asymmetries for the Delta(1232) in the exclusive channel (polarized-p polarized-e,e-prime p)pi0 obtained at Jefferson Lab in the Q2 range from 0.5 to 1.5 gev2 are presented. Results of the asymmetries are compared with the unitary isobar model, dynamical models, and the effective Lagrangian theory. Sensitivity to the different models was observed, particularly in relation to the description of background terms on which the target asymmetry depends significantly.

  14. The characteristics and origins of carbonaceous aerosol at a rural site of PRD in summer of 2006

    Directory of Open Access Journals (Sweden)

    W. W. Hu

    2012-02-01

    Full Text Available Both organic carbon (OC and elemental carbon (EC were measured during PRIDE-PRD 2006 summer campaign by using a semi-continuous thermal-optical carbon analyzer at a rural site, Back Garden (BG, which is located 50 km to the northwest of Guangzhou City. Together with the online EC/OC analyzer, various kinds of instruments related to aerosol chemical properties were employed here, which provided a good opportunity to check data quality. The concentrations of OC correlated well with the mass of organic matter (OM and water soluble organic carbon (WSOC, implying the reliability of the data measured in this campaign. The average OC concentrations in fine particle for three typical periods during the campaign (local emission influence, typhoon and precipitation and normal days were 28.1 μgC m−3, 4.0 μgC m−3 and 5.7 μgC m−3, respectively; and EC were 11.6 μgC m−3, 1.8 μgC m−3, and 3.3 μgC m−3, respectively. The diurnal patterns of EC and OC during the campaign were higher at night and in early morning than daytime, which was probably caused by the primary emission and accumulation in the occurrence of low boundary layer. Compared with the constant diurnal enhancement ratios of EC, the enhancement ratio of OC (OC versus (CO-CObackground kept in a relative high level in the afternoon, with a similar diurnal profile to oxygenated organic aerosol (OOA, due to the strong photochemical formation of OC. Here, a modified EC tracer method was used to estimate the formation of secondary organic carbon (SOC. These results showed that the average SOC concentration (normal days at BG site was about 2.0 ± 2.3 μgC m−3, and the SOC fraction in OC could reach up to 80% with the average of 47%. The modified approach in this study proved to be effective and reliable for SOC estimation based on good correlations between estimated SOC versus OOA or WSOC, and

  15. Extensive junctional diversity of rearranged human T cell receptor delta genes.

    Science.gov (United States)

    Hata, S; Satyanarayana, K; Devlin, P; Band, H; McLean, J; Strominger, J L; Brenner, M B; Krangel, M S

    1988-06-10

    The human T cell receptor delta (TCR delta) gene encodes one component of the TCR gamma delta-CD3 complex found on subsets of peripheral blood and thymic T cells. Human TCR delta diversity was estimated by characterizing rearrangements in TCR gamma delta cell lines and determining the structures of complementary DNA clones representing functional and nonfunctional transcripts in these cell lines. One V delta segment and one J delta segment were identified in all functional transcripts, although a distinct J delta segment was identified in a truncated transcript. Further, one D delta element was identified, and evidence for the use of an additional D delta element was obtained. Thus human TCR delta genes appear to use a limited number of germline elements. However, the apparent use of two D delta elements in tandem coupled with imprecise joining and extensive incorporation of N nucleotides generates unprecedented variability in the junctional region.

  16. Long-term impacts of aerosols on precipitation and lightning over the Pearl River Delta megacity area in China

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2011-12-01

    Full Text Available Seven-year measurements of precipitation, lightning flashes, and visibility from 2000 to 2006 have been analyzed in the Pearl River Delta (PRD region, China, with a focus on the Guangzhou megacity area. Statistical analysis shows that the occurrence of heavy rainfall (>25 mm per day and frequency of lightning strikes are reversely correlated to visibility during this period. To elucidate the effects of aerosols on cloud processes, precipitation, and lightning activity, a cloud resolving – Weather Research and Forecasting (CR-WRF model with a two-moment bulk microphysical scheme is employed to simulate a mesoscale convective system occurring on 28 Match 2009 in the Guangzhou megacity area. The model predicted evolutions of composite radar reflectivity and accumulated precipitation are in agreement with measurements from S-band weather radars and automatic gauge stations. The calculated lightning potential index (LPI exhibits temporal and spatial consistence with lightning flashes recorded by a local lightning detection network. Sensitivity experiments have been performed to reflect aerosol conditions representative of polluted and clean cases. The simulations suggest that precipitation and LPI are enhanced by about 16% and 50%, respectively, under the polluted aerosol condition. Our results suggest that elevated aerosol loading suppresses light and moderate precipitation (less than 25 mm per day, but enhances heavy precipitation. The responses of hydrometeors and latent heat release to different aerosol loadings reveal the physical mechanism for the precipitation and lightning enhancement in the Guangzhou megacity area, showing more efficient mixed phase processes and intensified convection under the polluted aerosol condition.

  17. 长三角地区低碳城市发展潜力分析%Analysis on Development Potential of Low Carbon City in the Yangtze River Delta Region

    Institute of Scientific and Technical Information of China (English)

    叶懿安; 朱继业; 王琦

    2012-01-01

    以分析城市低碳发展潜力为目标,确定了低碳潜力分析的指标.在分析了长江三角洲地区16个城市的社会经济特征和能量消耗特征的基础上,采用弹性系数的变化特征作为研究的重要工具,并用聚类方法对长三角地区16个城市的低碳经济发展潜力进行了聚类分析.从潜力特征发现各城市低碳发展过程中存在的问题,并对长三角地区低碳经济发展战略提出了建议.%This paper determined the index to analyze the potential of urban low carbon development. Based on the analysis of 16 cities in the Yangtze River Delta region's socio-economic characteristics and energy consumption characteristics,the paper used the elastic coefficient of variation as an important research tool,and cluster analyzed the development potential of low carbon economy of the 16 cities. The paper found the problems in the development process of low carbon cities from the potential features,and gave suggestions on low carbon economic development strategy for the Yangtze River Delta region.

  18. Research on Regional Integrated Transport System Planning of the Yangtze River Delta%长江三角洲区域交通一体化规划研究

    Institute of Scientific and Technical Information of China (English)

    邵瑛

    2012-01-01

    The transport system construction is an important aspect to promote the regional integration, it is also the necessary conditions of the sustainable economic and social development in Yangtze River Delta. This article from the global perspective, based on the national strategy, in the basis of analyzing the current situation, put forward transportation integration planning goal and development strategy of the Yangtse River delta so as to realize the regional common development and prosperity.%长江三角洲交通体系建设是推动区域一体化的重要方面,也是长江三角洲经济社会可持续发展的必要条件。从全球视野的角度,立足国家战略,在对现状深入解读的基础上,提出长江三角洲区域交通一体化规划目标和发展策略,以实现区域共同发展、共同繁荣为目的。

  19. Atmospheric hydrogen peroxide and organic hydroperoxides during PRIDE-PRD'06, China: their concentration, formation mechanism and contribution to secondary aerosols

    Directory of Open Access Journals (Sweden)

    W. Hua

    2008-11-01

    Full Text Available Atmospheric hydrogen peroxide (H2O2 and organic hydroperoxides were measured from 18 to 30 July in 2006 during the PRIDE-PRD'06 campaign at Backgarden, a rural site located 48 km north of Guangzhou, a mega-city in southern China. A ground-based instrument was used as a scrubbing coil collector to sample ambient air, followed by on-site analysis by high-performance liquid chromatography (HPLC coupled with post-column derivatization and fluorescence detection. The H2O2 mixing ratio over the 13 days ranged from below the detection limit to a maximum of 4.6 ppbv, with a mean (and standard deviation of (1.26±1.24 ppbv during the daytime (08:00–20:00 LT. Methyl hydroperoxide (MHP, with a maximum of 0.8 ppbv and a mean (and standard deviation of (0.28±0.10 ppbv during the daytime, was the dominant organic hydroperoxide. Other organic peroxides, including bis-hydroxymethyl hydroperoxide (BHMP, peroxyacetic acid (PAA, hydroxymethyl hydroperoxide (HMHP, 1-hydroxy-ethyl hydroperoxide (1-HEHP and ethyl hydroperoxide (EHP, were detected occasionally. The concentration of H2O2 exhibited a pronounced diurnal variation on sunny days, with a peak mixing ratio in the afternoon (12:00–18:00 LT, but lacked an explicit diurnal cycle on cloudy days. Sometimes a second peak mixing ratio of H2O2 was observed during the evening, suggesting that H2O2 was produced by the ozonolysis of alkenes. The diurnal variation profile of MHP was, in general, consistent with that of H2O2. The estimation indicated that in the morning the H2O2 detected was formed mostly through local photochemical activity, with the rest probably attributable to vertical transport. It is notable that relatively high levels of H2O2 and MHP were found in polluted air. The unexpectedly high level of HO2 radicals

  20. Genomic organization of the human T-cell antigen-receptor alpha/delta locus.

    Science.gov (United States)

    Satyanarayana, K; Hata, S; Devlin, P; Roncarolo, M G; De Vries, J E; Spits, H; Strominger, J L; Krangel, M S

    1988-11-01

    Two clusters of overlapping cosmid clones comprising about 100 kilobases (kb) at the human T-cell antigen-receptor alpha/delta locus were isolated from a genomic library. The structure of the germ-line V delta 1 variable gene segment was determined. V delta 1 is located 8.5 kb downstream of the V alpha 13.1 gene segment, and both V segments are arranged in the same transcriptional orientation. The V alpha 17.1 segment is located between V delta 1 and the D delta, J delta, C delta region (containing the diversity, joining, and constant gene segments). Thus, V delta and V alpha segments are interspersed along the chromosome. The germ-line organization of the D delta 2, J delta 1, and J delta 2 segments was determined. Linkage of C delta to the J alpha region was established by identification of J alpha segments within 20 kb downstream of C delta. The organization of the locus was also analyzed by field-inversion gel electrophoresis. The unrearranged V delta 1 and D delta, J delta, C delta regions are quite distant from each other, apparently separated by a minimum of 175-180 kb.

  1. A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Functions of Forested Wetlands in the Delta Region of Arkansas, Lower Mississippi River Alluvial Valley, Version 2.0

    Science.gov (United States)

    2011-09-01

    70  Function 3: Cycle nutrients ...to import, store, cycle, and export nutrients (Brinson et al. 1980, Wharton et al. 1982). Although these conditions have changed dramatically in...explorations of the Arkansas Delta in the 16th century, natural levees of the Mississippi and Arkansas Rivers were extensively used for maize agriculture by

  2. The Effects of Socioeconomic and Environmental Factors on the Incidence of Dengue Fever in the Pearl River Delta, China, 2013.

    Directory of Open Access Journals (Sweden)

    Xiaopeng Qi

    2015-10-01

    Full Text Available An outbreak of dengue fever (DF occurred in Guangdong Province, China in 2013 with the highest number of cases observed within the preceding ten years. DF cases were clustered in the Pearl River Delta economic zone (PRD in Guangdong Province, which accounted for 99.6% of all cases in Guangdong province in 2013. The main vector in PRD was Aedes albopictus. We investigated the socioeconomic and environmental factors at the township level and explored how the independent variables jointly affect the DF epidemic in the PRD.Six factors associated with the incidence of DF were identified in this project, representing the urbanization, poverty, accessibility and vegetation, and were considered to be core contributors to the occurrence of DF from the perspective of the social economy and the environment. Analyses were performed with Generalized Additive Models (GAM to fit parametric and non-parametric functions to the relationships between the response and predictors. We used a spline-smooth technique and plotted the predicted against the observed co-variable value. The distribution of DF cases was over-dispersed and fit the negative binomial function better. The effects of all six socioeconomic and environmental variables were found to be significant at the 0.001 level and the model explained 45.1% of the deviance by DF incidence. There was a higher risk of DF infection among people living at the prefectural boundary or in the urban areas than among those living in other areas in the PRD. The relative risk of living at the prefectural boundary was higher than that of living in the urban areas. The associations between the DF cases and population density, GDP per capita, road density, and NDVI were nonlinear. In general, higher "road density" or lower "GDP per capita" were considered to be consistent risk factors. Moreover, higher or lower values of "population density" and "NDVI" could result in an increase in DF cases.In this study, we presented an

  3. Organosulfates from pinene and isoprene over the Pearl River Delta, South China: seasonal variation and implication in formation mechanisms.

    Science.gov (United States)

    He, Quan-Fu; Ding, Xiang; Wang, Xin-Ming; Yu, Jian-Zhen; Fu, Xiao-Xin; Liu, Teng-Yu; Zhang, Zhou; Xue, Jian; Chen, Duo-Hong; Zhong, Liu-Ju; Donahue, Neil M

    2014-08-19

    Biogenic organosulfates (OSs) are important markers of secondary organic aerosol (SOA) formation involving cross reactions of biogenic precursors (terpenoids) with anthropogenic pollutants. Until now, there has been rare information about biogenic OSs in the air of highly polluted areas. In this study, fine particle (PM2.5) samples were separately collected in daytime and nighttime from summer to fall 2010 at a site in the central Pearl River Delta (PRD), South China. Pinene-derived nitrooxy-organosulfates (pNOSs) and isoprene-derived OSs (iOSs) were quantified using a liquid chromatograph (LC) coupled with a tandem mass spectrometer (MS/MS) operated in negative electrospray ionization (ESI) mode. The pNOSs with MW 295 exhibited higher levels in fall (151 ± 86.9 ng m(-3)) than summer (52.4 ± 34.0 ng m(-3)), probably owing to the elevated levels of NOx and sulfate in fall when air masses mainly passed through city clusters in the PRD and biomass burning was enhanced. In contrast to observations elsewhere where higher levels occurred at nighttime, pNOS levels in the PRD were higher during the daytime in both seasons, indicating that pNOS formation was likely driven by photochemistry over the PRD. This conclusion is supported by several lines of evidence: the specific pNOS which could be formed through both daytime photochemistry and nighttime NO3 chemistry exhibited no day-night variation in abundance relative to other pNOS isomers; the production of the hydroxynitrate that is the key precursor for this specific pNOS was found to be significant through photochemistry but negligible through NO3 chemistry based on the mechanisms in the Master Chemical Mechanism (MCM). For iOSs, 2-methyltetrol sulfate ester which could be formed from isoprene-derived epoxydiols (IEPOX) under low-NOx conditions showed low concentrations (below the detection limit to 2.09 ng m(-3)), largely due to the depression of IEPOX formation by the high NOx levels over the PRD.

  4. Powerful flaring configurations in solar active regions: magnetic topology via special features of delta-structure phenomenon. I. Basic principles of topological model

    CERN Document Server

    Ikhsanov, R N; Marushin, Yu.V.

    2003-01-01

    The close connection of magnetic field structure on the one hand and observable features of complex ARs with high flare efficiency on the other one is investigated in frames of so-called dynamic classification of flaring magnetic configurations (FMC) and the simple topological model of interacting magnetic complexes (IMC) suggested by Ikhsanov (1982). The primary objective of the present work is to expose general statements of the specified model and classification, the secondary one assumes the critical analysis and logical generalization of several important regularities being frequently observable in evolution stages of a typical complex AR with powerful flares including proton ones. Those cases are basically examined where the development of photospheric situation was marked by the formation of delta-configuration phenomenon described by Kunzel (1960) as one of the most impressive precursors of high flare activity. Without trying to use any additional assumptions and alternative hypotheses, the qualitativ...

  5. 长三角地区能源消费与区域发展相互关系及其影响因素%RELATIONSHIP BETWEEN ENERGY CONSUMPTION AND REGIONAL DEVELOPMENT AND ITS DETERMINANTS IN THE YANGTZE RIVER DELTA

    Institute of Scientific and Technical Information of China (English)

    邹沛思; 贺灿飞

    2011-01-01

    以长三角地区上海、江苏和浙江3省市为研究对象,运用Johansen协整检验、向量误差修正模型(VEC)和Granger因果检验等方法分析能源消费与经济发展的相互关系,并利用LMDI方法对3省市1995~2007年的能源强度进行分解分析,得到能源消费与区域发展关系的影响因素。结果表明:近年来长三角能源消费形势严峻,并较多地受到产业结构调整的影响。上海和江苏的能源消费在一定程度上拉动了经济发展,但是随着产业结构的调整,上海工业结构的调整促进了能源强度降低,而江苏却正好相反。近年来,浙江省的经济发展对能源消费的%Energy consumption contributes to the emission of greenhouse gases,which is arguably responsible for the global warming.As one of the most developed regions in China,the Yangtze River Delta is both a cause and victim of global and regional climate change.The understanding of the relationship between energy consumption and economic development in the Yangtze River Delta would help local governments to designate effective strategies to mitigate the impact of climate change and to enhance their adaptation capabilities to climate change.This study applied Johansen integration test,VEC model and Granger Causality Test to uncover the relationship between energy consumption and regional development in the Yangtze River Delta.The logarithmic mean Divisia index techniques(LMDI) was used to decompose changes in energy intensity to identify the key factors that influence the relationship between energy consumption and regional development.Some interesting differences in the relationship between energy consumption and economic development among Shanghai,Jiangsu and Zhejiang were found in this study.In Shanghai and Jiangsu,energy consumption resulted in economic growth,although in Jiangsu,this influence was not so significant.But in the Zhejiang province,economic growth led to more energy consumption

  6. Spatial-temporal distribution of phthalate esters from riverine outlets of Pearl River Delta in China.

    Science.gov (United States)

    Li, Ting; Yin, Pinghe; Zhao, Ling; Wang, Guifang; Yu, Qiming Jimmy; Li, Huanyong; Duan, Shunshan

    2015-01-01

    The aquatic environments of the Pearl River Delta (PRD) in China have been contaminated by various industrial chemicals from local industries. In this study, the spatial-temporal distribution of six priority phthalate esters (PAEs) in surface water and sediments from the PRD was investigated. The PAEs were detected with total concentrations (Σ6PAEs) ranging from 0.35 to 20.70 μg L⁻¹ in surface water and dry weight ranging from 0.88 to 5.69 μg g⁻¹ in sediments. The Σ6PAEs concentrations in surface water were higher in the wet season than those in the dry season, while the opposite pattern was observed in sediments. Di(2-ethylhexyl) phthalate (DEHP) was the most abundant congener, which was higher than those reported in the literature. Risk quotients for relevant aquatic organisms were obtained and showed that most of these PAEs, in particular, butyl benzyl phthalate, DEHP and di-n-octyl phthalate, have significant potential health and ecological risks for the aquatic environment studied.

  7. Characterizing and sourcing ambient PM2.5 over key emission regions in China I: Water-soluble ions and carbonaceous fractions

    Science.gov (United States)

    Zhou, Jiabin; Xing, Zhenyu; Deng, Junjun; Du, Ke

    2016-06-01

    During the past decade, huge research resources have been devoted into studies of air pollution in China, which generated abundant datasets on emissions and pollution characterization. Due to the complex nature of air pollution as well as the limitations of each individual investigating approach, the published results were sometimes perplexing and even contradicting. This research adopted a multi-method approach to investigate region-specific air pollution characteristics and sources in China, results obtained using different analytical and receptor modeling methods were inter-compared for validation and interpretation. A year-round campaign was completed for comprehensive characterization of PM2.5 over four key emission regions: Beijing-Tianjin-Hebei (BTH), Yangzi River Delta (YRD), Pearl River Delta (PRD), and Sichuan Basin (SB). Atmospheric PM2.5 samples were collected from 10/2012 to 08/2013 at four regional sites, located on the diffusion paths of air masses from their corresponding megacities (i.e., Beijing, Shanghai, Guangzhou, and Chengdu). The annual average PM2.5 mass concentrations showed distinct regional difference, with the highest observed at BTH and lowest at PRD site. Nine water-soluble ions together contributed 33-41% of PM2.5 mass, with three dominant ionic species being SO42-, NO3-, NH4+, and carbonaceous particulate matter contributed 16-23% of PM2.5 mass. This implied that combustion and secondary formation were the main sources for PM2.5 in China. In addition, SO42-, NO3-, NH4+, and carbonaceous components (OC, EC) showed clear seasonal patterns with the highest concentration occurring in winter while the lowest in summer. Principal component analysis performed on aerosol data revealed that vehicular emissions, coal/biomass combustion, industry source, soil dust as well as secondary formation were the main potential sources for the ionic components of PM2.5. The characteristic chemical species combined with back trajectory analysis indicated

  8. Observation study on the structure of wind and temperature in the boundary layer and its impact on air quality over the Pearl River Delta,China

    Science.gov (United States)

    Fan, S.; Zhu, W.; Wu, M.; Li, H.; Liao, Z.; Fan, Q.

    2015-12-01

    The structure of wind and temperature in the boundary layer and its impact on air quality over the Pearl River Delta(PRD) were examined through five intensive observations in October 2004 July 2006, November 2008 December 2013 and October 2014.The results show that the structure of wind and temperature in boundary layer has significant relationship with the underlying surface, geographical environment, season, weather systems, and has direct impact on air quality. Two types of typical weather conditions associated with poor air quality over PRD. The first is the warm period before a cold front (WPBCF) and the second is the subsidence period controlled by a tropical cyclone (SPCTC). In both cases, quiet small wind and stabilize weather obvious wind shear and multi-layer inversion appear. There will be a phenomenon "the gray in near ground layer, but blue sky in upper layer" some time, the reason is that the Mountain of Nanling and the heat island effect of urban area of PRD has weakened effect to the low-level cold air the upper-level cold air has reached, but the low-level cold air has not reach or is not strength enough to remove pollutants. Within the boundary layer, especially near ground small wind speed, ground inversion or multi-layer inversion, stable stratification, lower mixing layer height, insufficient horizontal transportation and vertical diffusion ability, combination with the negative impact of sea-land breeze urban heat island circulation, would be the main reasons of the most time poor air quality of PRD.

  9. Assessing the effects of urbanization on the environment with soil legacy and current-use insecticides: a case study in the Pearl River Delta, China.

    Science.gov (United States)

    Wei, Yan-Li; Bao, Lian-Jun; Wu, Chen-Chou; He, Zai-Cheng; Zeng, Eddy Y

    2015-05-01

    To evaluate the impacts of anthropogenic events on the rapid urbanized environment, the levels of legacy organochlorine pesticides (OCPs) and current-use insecticides (CUPs), i.e., dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs), pyrethroids and organophosphates in soil of the Pearl River Delta (PRD) and surrounding areas were examined. Spatial concentration distributions of legacy OCPs and CUPs shared similar patterns, with higher concentrations occurred in the central PRD with more urbanization level than that in the PRD's surrounding areas. Furthermore, relatively higher concentrations of OCPs and CUPs were found in the residency land than in other land-use types, which may be attributed to land-use change under rapid urbanization. Moderate correlations between gross domestic production or population density and insecticide levels in fifteen administrative districts indicated that insecticide spatial distributions may be driven by economic prosperity. The soil-air diffusive exchanges of DDTs and HCHs demonstrated that soil was a sink of atmospheric o,p'-DDE, o,p'-DDD, p,p'-DDD and o,p'-DDT, and was a secondary source of HCHs and p,p'-DDT to atmosphere. The soil inventories of DDTs and HCHs (100 ± 134 and 83 ± 70 tons) were expected to decrease to half of their current values after 18 and 13 years, respectively, whereas the amounts of pyrethroids and organophosphates (39 and 6.2 tons) in soil were estimated to decrease after 4 and 2 years and then increase to 87 and 1.0 tons after 100 years. In this scenario, local residents in the PRD and surrounding areas will expose to the high health risk for pyrethroids by 2109. Strict ban on the use of technical DDTs and HCHs and proper training of famers to use insecticides may be the most effective ways to alleviate the health effect of soil contamination.

  10. Study of "zero consumption" in Sports and Leisure Activity in the Elderly Living in the Yangtze River Delta Region%长三角地区老年人运动休闲的"零消费"现象

    Institute of Scientific and Technical Information of China (English)

    蔡任; 张建国; 钱佳佳

    2015-01-01

    调查长三角地区老年人运动休闲的"零消费"现状,分析其特征及产生原因. 使用问卷调查、访谈等方法获取有关长三角地区老年人运动休闲消费的相关数据. 结果表明:老年人运动休闲的"零消费"是我国长三角地区中较为普遍存在的一种社会现象,它不仅是经济收入水平制约的结果,而且也是年龄增长、体力水平下降等多种因素作用下形成的一种消费趋势. 老年人运动休闲的"零消费"对老年人参与运动休闲活动本身并无明显影响,但是会在一定程度上影响运动休闲活动的多样化发展. 就目前我国老年人的运动休闲活动参与现状而言,尚无法像发达国家一样对休闲产业的发展起到举足轻重的引领作用.%The paper investigates the Yangtze River Delta region the elderly sports "zero consumption" situation and analyzes its characteristics and causes. It uses questionnaires, interviews and other methods to obtain information about the Yangtze River Delta region of elderly leisure sports consumption related data. Conclusion: the elderly sports "zero consumption" is China's Yangtze River Delta region in the more widespread the phenomenon of a kind of society, it is not only economic income level constraints results, but also the age, physical decline and other factors contributed to a trend in consumption. The elderly sports "zero consumption" for the elderly participation in recreational sports activities is not significantly affected, but will be affected to a certain extent sports leisure activity diversification development. Current our country older sports leisure activity participation situation is concerned, is not as developed as the leisure industry and the development to play a decisive role in the leading role.

  11. A Spatial Analysis of Regional Economic Convergence at City Level in the Pearl River Delta%珠三角地区县域经济增长收敛的空间计量分析

    Institute of Scientific and Technical Information of China (English)

    张婷; 李红

    2013-01-01

      文章运用空间计量分析方法,以珠三角1997-2011年24个县市级人均GDP为样本,对区域经济增长的空间相关性和收敛性进行实证研究。结果表明:1997-2011年,珠三角24个县域经济增长具有显著的空间正相关,在地理空间上存在集聚现象。与传统空间计量模型对比,文章选用能消除区域经济增长的空间依赖性的空间误差模型,研究发现:各县市间存在β-收敛,珠三角地区经济增长不仅受到自身初始水平的影响,还会对周围地区的经济增长具有扩散作用。因此,在制定区域政策时,应充分考虑经济发展的空间依赖性和溢出效应。%  With the per capita GDP growth between 24 cities and counties in the Pearl River Delta from 1997 to 2011,the pa⁃per uses spatial econometric analysis method to test the spatial correlation and convergence of regional economic growth. The re⁃sults show that the economic growth of the 24 cities and counties has a significant spatial positive correlation and geospatial ag⁃glomeration in the Pearl River Delta. Compared with the traditional spatial econometric model,this paper selected the spatial error model,which can eliminate the spatial dependence of regional economic growth,to reach the founding:the β-conver⁃gence existed among the cities and counties,and the Pearl River Delta economic growth is not only influenced by the initial lev⁃els,but also conducted diffusing effect to the economic growth of the surrounding regions. Therefore,the development of re⁃gional policy should take full account of the spatial dependence and spillover effects of the economic development.

  12. The Effects of the Chemical Components of Soil Salinity on Electrical Conductivity in the Region of the Delta Oasis of Weigan and Kuqa Rivers,China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Fei; Tashpolat Tiyip; DING Jian-li; Gregory N Taff; HE Qi-sheng

    2009-01-01

    In order to assess the effects of chemical properties of soil salinity on electrical conductivity of 1:5 soil/water extract (EC1:5), the study focused on revealing the main chemical factors contributing to EC of soil extracts and their relative importance. The relationship between EC1:5 and the chemical properties of soil salinity in the delta oasis of Weigan and Kuqa rivers, China, were studied using path coefficient analysis, a path analysis method. We studied each key element affecting EC1:5 either directly or indirectly. The results obtained show that the salt content, total dissolved solids (TDS),and the sum of the sodium ion concentration and the kalium ion concentration are the most influential factors on 1:5 soil/water extract (EC1:5) in the 0-10 cm and the 30-50 cm soil layer. The results show that the sequence of direct path coefficients in the 0-10 cm and the 30-50 cm soil layers on soil conductivity is TDS→ Na+ + K+→Salt content→ Ca2+→Cl-→ the sodium dianion ratio (SDR)→ pH → SO42-→ HCO3-→ Mg2+→ the soluble sodium percentage (SSP)→sodium absorption ratio (SAR) and TDS→ Salt content→Na+ + K+→ Ca2+→ SDR→ Mg2+→ HCO3-→SSP→pHSO42-→ SAR→CI-. The salt content, chlorine ion, and SAR are the main factors affecting 1:5 soil/water extract (ECt1:5) in the 10-30 centimeter soil layer. The order of direct path coefficients result is as follows: Salt content→Cl-→SAR→SSP→TDS→Ca2+→Mg2+= SO42-→HCO3-→pH→SDR→Na+ + K+. Moreover, the effects of HCO3-, pH were very weak.Though the direct path coefficients between EC1:5 and SAR, SO42- and Ca2+ were not high, influence of other chemical factors caused the coefficients to increase, making the summation of their direct and indirect path coefficients relatively high. The models of the different soil layers were structured separately. Evidences showed that multiple regression relations between EC1:5 and most of the primary factors had sound reliability and very good

  13. Delta hedging strategies comparison

    DEFF Research Database (Denmark)

    De Giovanni, Domenico; Ortobelli, S.; Rachev, S.T.

    2008-01-01

    In this paper we implement dynamic delta hedging strategies based on several option pricing models. We analyze different subordinated option pricing models and we examine delta hedging costs using ex-post daily prices of S&P 500. Furthermore, we compare the performance of each subordinated model ...

  14. Influence of groundwater on the degradation of irrigated soils in a semi-arid region, the inner delta of the Niger River, Mali

    Science.gov (United States)

    Valenza, A.; Grillot, J. C.; Dazy, J.

    2000-08-01

    The problem of soil degradation through alkalinization/salinization in an irrigated area with a semi-arid climate was examined in the inner delta of the Niger River, Mali, by the study of groundwater hydraulics and hydrochemistry in an area recharged by irrigation water. On the basis of data analysis on various scales, it is concluded that the current extent of the surface saline soils is due to a combination of three factors: (1) the existence of ancient saline soils (solonchaks) resulting from the creation of a broad sabkha west of the former course of the Niger River, now called the Fala of Molodo. These saline crusts were gradually deposited during the eastward tilting of the tectonic block that supports the Niger River; (2) the irrigation processes during the recent reflooding of the Fala of Molodo (river diversion in 1950). These used very poorly mineralized surface water but reintroduced into the alluvial groundwater system - generally of a low permeability (K=10-6 m s-1) - salts derived from the ancient solonchaks; and (3) the redeposition of the dissolved salts on the surface due to the intense evapotranspiration linked to the present Sahelian climate. In this context, only efficient artificial draining of subsurface alluvial groundwater can eliminate most of the highly mineralized flow and thus reduce the current saline deposits.

  15. In vitro isolation and infection intensity of Rickettsia parkeri in Amblyomma triste ticks from the Paraná River Delta region, Argentina.

    Science.gov (United States)

    Monje, Lucas D; Nava, Santiago; Antoniazzi, Leandro R; Colombo, Valeria C; Beldomenico, Pablo M

    2014-10-01

    In the present study, we report the first in vitro isolation and infection intensity of Rickettsia parkeri in Amblyomma triste ticks from Argentina. No genetic differences in the molecular targets evaluated were found between R. parkeri isolates from Argentina and those R. parkeri isolates reported in Uruguay and Brazil, both obtained from A. triste. Only a minor difference was observed when compared to R. parkeri isolated from Amblyomma maculatum from United States. Moreover, the prevalence of infection by R. parkeri in ticks collected from the vegetation in the Paraná Delta was high (20.4%). Interestingly, the distribution of R. parkeri infection intensity observed in A. triste ticks was distinctly bimodal, with approximately 60% of the infected ticks presenting high rickettsial loads (3.8×10(5)-4.5×10(7) ompA copies/tick) and the remainder with low rickettsial levels (5.6×10(1)-6.5×10(3) ompA copies/tick). This bimodality in R. parkeri infection intensity in ticks could determine differences in the severity of the disease, but also be important for the infection dynamics of this pathogen. Further research exploring the distribution of rickettsial infection levels in ticks, as well as its determinants and implications, is warranted.

  16. Regional Comparison of Cultural Industries in the Yangtze River Delta%长三角文化产业区域比较

    Institute of Scientific and Technical Information of China (English)

    胡慧源

    2015-01-01

    Based on the data of 2012-2013 from the National Bureau of Statistics, this paper conducts a comparative study on cultural industries in the Yangtze River Delta from the aspects of industrial scale, market demand, production and operation, spatial concentration, and key categories. It is concluded that Shanghai has an advantage in the aspects of operational efficiency, digital publishing, and online games, while Jiangsu is better in industrial scale, fixed investment, and R&D. Comparatively, Zhejiang’s enterprise competitiveness is outstanding.%基于2012~2013年相关统计数据,本文从产业规模、市场需求、生产运营、空间集聚、重点门类等方面对长三角文化产业进行了比较研究。结果表明,上海文化产业的经营效益远远高于江苏、浙江地区,在数字出版和网络游戏两个门类具有明显优势;产业规模、固定资产投资和R&D是江苏文化产业的比较优势所在;浙江在各个方面的表现较为平稳,文化企业的竞争力较为突出。

  17. Current levels and composition profiles of PBDEs and alternative flame retardants in surface sediments from the Pearl River Delta, southern China: Comparison with historical data

    Energy Technology Data Exchange (ETDEWEB)

    Chen, She-Jun [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Feng, An-Hong; He, Ming-Jing; Chen, Man-Ying [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Luo, Xiao-Jun [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Mai, Bi-Xian, E-mail: nancymai@gig.ac.cn [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2013-02-01

    Polybrominated diphenyl ethers (PBDEs) and alternative flame retardants were measured in surface sediments collected during 2009–2010 from the Pearl River Delta, southern China (a large manufacturing base for electronics/electrical products), to evaluate the influence of China's RoHS directive (adopted in 2006) on their environmental occurrence. The concentrations in sediments from different water systems ranged from 3.67 to 2520 ng/g (average of 17.1–588 ng/g) for PBDEs and from 0.22 to 5270 ng/g (average of 11.3–454 ng/g) for the alternative retardants. Although the PBDE levels have decreased significantly compared with those in sediments collected in 2002 in this region, the levels of alternative decabromodiphenyl ethane (DBDPE) have exceeded those of BDE209 (two predominant halogenated flame retardants (HFRs) in China) in the majority of sediments. This finding suggests a different contaminant pattern of HFRs in current sediments due to the replacement of the deca-BDE mixture with DBDPE in this region. In addition, sediment concentrations of discontinued PBDEs in the rural area are clearly elevated due to e-waste dismantling. The congener profiles of PBDEs in the current sediments (with more abundant lower-brominated congeners) differed substantially from those in 2002 and from the technical products, suggesting that biological or photolytic debromination of PBDEs may have occurred in the environment. - Highlights: ► PBDE levels in sediments have decreased substantially since China's RoHS directive. ► Contamination of novel DBDPE has exceeded that of deca-BDE in the PRD sediments. ► The congener profiles of PBDEs in the sediments have changed significantly. ► Significant biological or photolytic degradation of PBDEs may occur in the environment.

  18. A modeling study on the effect of urban land surface forcing to regional meteorology and air quality over South China

    Science.gov (United States)

    Zhu, Kuanguang; Xie, Min; Wang, Tijian; Cai, Junxiong; Li, Songbing; Feng, Wen

    2017-03-01

    The change of land-use from natural to artificial surface induced by urban expansion can deeply impact the city environment. In this paper, the model WRF/Chem is applied to explore the effect of this change on regional meteorology and air quality over South China, where people have witnessed a rapid rate of urbanization. Two sets of urban maps are adopted to stand for the pre-urbanization and the present urban land-use distributions. Month-long simulations are conducted for January and July, 2014. The results show that urban expansion can obviously change the weather conditions around the big cities of South China. Especially in the Pearl River Delta region (PRD), the urban land-use change can increase the sensible heat flux by 40 W/m2 in January and 80 W/m2 in July, while decrease the latent heat flux about -50 W/m2 in January and -120 W/m2 in July. In the consequent, 2-m air temperature (T2) increases as much as 1 °C and 2 °C (respective to January and July), planetary boundary layer height (PBLH) rises up by 100-150 m and 300 m, 10-m wind speed (WS10) decreases by -1.2 m/s and -0.3 m/s, and 2-m specific humidity is reduced by -0.8 g/kg and -1.5 g/kg. Also, the precipitation in July can be increased as much as 120 mm, with more heavy rains and rainstorms. These variations of meteorological factors can significantly impact the spatial and vertical distribution of air pollutants as well. In PRD, the enhanced updraft can reduce the surface concentrations of PM10 by -40 μg/m3 (30%) in January and -80 μg/m3 (50%) in July, but produce a correlating increase in the concentrations at higher atmospheric layers. However, according to the increase in T2 and the decrease in surface NO, the surface concentrations of O3 in PRD can increase by 2-6 ppb in January and 8-12 ppb in July. Meanwhile, there is a significant increase in the O3 concentrations at upper layers above PRD, which should be attributed to the increase in air temperature and the enhanced upward transport of

  19. Measurement of the Polarized Structure Function sigma {sub LT'} for (p{rvec e},e'p) pi{sup 0} in the Delta (1232) Resonance Region

    Energy Technology Data Exchange (ETDEWEB)

    Kyungseon Joo; L.C. Smith; V.D. Burkert; R. Minehart

    2003-05-01

    The polarized longitudinal-transverse structure function {sigma}{sub LT'} has been measured for the first time in the {Delta}(1232) resonance region at Q{sup 2} = 0.40 and 0.65 GeV{sup 2}. Data for the p{rvec e},e'p {pi}{sup 0} reaction were taken at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. Evidence for interference between resonant and non-resonant amplitudes is discussed using a partial wave analysis. Comparison with previous beam asymmetry measurements at MAMI indicate a deviation from the predicted Q{sup 2} dependence of {sigma}{sub LT'} using recent phenomenological models.

  20. Horizontal Symmetries $\\Delta(150)$ and $\\Delta(600)$

    CERN Document Server

    Lam, C S

    2013-01-01

    Using group theory of mixing to examine all finite subgroups of SU(3) with an order less than 512, we found recently that only the group $\\Delta(150)$ can give rise to a correct reactor angle $\\th_{13}$ of neutrino mixing without any free parameter. It predicts $\\sin^22\\th_{13}=0.11$ and a sub-maximal atmospheric angle with $\\sin^22\\th_{23}=0.94$, in good agreement with experiment. The solar angle $\\th_{12}$, the CP phase $\\d$, and the neutrino masses $m_i$ are left as free parameters. In this article we provide more details of this case, discuss possible gain and loss by introducing right-handed symmetries, and/or valons to construct dynamical models. A simple model is discussed where the solar angle agrees with experiment, and all its mixing parameters can be obtained from the group $\\Delta(600)$ by symmetry alone. The promotion of $\\Delta(150)$ to $\\Delta(600)$ is on the one hand analogous to the promotion of $S_3$ to $S_4$ in the presence of tribimaximal mixing, and on the other hand similar to the extens...

  1. 新型城镇化背景下珠三角城镇群发展研究%The Development Research on New-type Urbanization in the Pearl River Delta Mega City-regions

    Institute of Scientific and Technical Information of China (English)

    袁媛; 古叶恒; 蒋珊红; 柳叶

    2014-01-01

    Based on qualitative and quantitative research methods, this paper firstly reviews urbanization process of the Pearl River Delta from the beginning of the opening reform. It contains three stages of start-up, rapid and stable development. There stil exist several problems, such as extensive land use and ecological destruction, social lagging in semi-urban area and imbalance of distribution and public services. Secondly, from the perspective of planning background, content and spatial structure evolution, it sums up characteristics of five previous regional plans. Thirdly, using New Urbanization Index (NUI), it evaluates spatial patterns of the Pearl River Delta from 1990-2010. There are dual-cores, great disparity between inside and outside circle, and higher level of NUI in centre and new districts. Last not least, three strategies for regional coordination are proposed.%回顾改革开放以来珠三角经历了城镇化启动、快速发展和稳定发展三大阶段,目前仍面临土地粗放利用和生态破坏、半城镇化地区发展滞后、分配与民生服务供给失衡等问题;采用定量与定性相结合的方法,从编制背景、规划内容、空间结构演变等分析了珠三角历次区域规划;针对珠三角新型城镇化呈现双核心空间结构、内外圈层和东中西部差异大、中心区和新城区的新型城镇水平较高等特点,提出对珠三角城镇群的发展构想。

  2. The Relationship between Sap Flow Density and  Environmental Factors in the Yangtze River Delta  Region of China

    Directory of Open Access Journals (Sweden)

    Xin Liu

    2017-03-01

    Full Text Available Canopy transpiration is an important component of evapotranspiration, integrating physical and biological processes within the water and energy cycles of forests. Quercus acutissima and Cunninghamia lanceolata are two important, fast‐growing and commercial tree species that have been extensively used for vegetation restoration, water conservation and building artificial forests in the Yangtze River Delta region of China. The primary objective of this study was to characterize sap flow densities of the two species by comparing daytime and nocturnal sap flow patterns and their relationships with environmental factors. Sap flow densities (Sd were measured between September 2012 and August 2013 using the commercially‐available thermal dissipation probes. Hourly meteorological data were measured in an open field, located 200 m away from the study site, including photosynthetically‐active radiation (Par, air temperature (Ta, relative air humidity (Rh, vapor pressure deficit (Vpd and precipitation (P. Soil water content (Swc data were logged hourly in different layers at Q. acutissima and C. lanceolata forests. Results indicated that the mean Sd in summer was higher than that in spring and autumn. Both the Sd of Q. acutissima and C. lanceolata showed distinct diurnal patterns. Nocturnal sap flow densities (Sdn were noticeable, and both species followed similar declining patterns during our study period. The daytime sap flow density (Sdd was more sensitive to environmental factors than Sdn. Sap flow density was significant linearly correlated with Par, Vpd and Ta, and Par and Vpd explained the greatest amount of variation in daytime sap flow of Q. acutissima and C. lanceolata, respectively. Our study will enrich knowledge of plantation forest physical and biological processes and provide valuable information for plantation forest management in the Yangtze River Delta region of China.

  3. Current status and temporal trend of heavy metals in farmland soil of the Yangtze River Delta Region: Field survey and meta-analysis.

    Science.gov (United States)

    Shao, Diwei; Zhan, Yu; Zhou, Wenjun; Zhu, Lizhong

    2016-12-01

    While the spatial distributions of heavy metals in farmland soil of China have been comprehensively delineated, their temporal trends are rarely investigated but are important for environmental risk management. In this study, the current status and temporal trends of heavy metals in the farmland soil of Yangtze River Delta (YRD) were evaluated through field survey and meta-analysis. The field survey conducted in 2014 showed that the concentrations of Cd, Pb, Cu, Zn, and Ni in the farmland topsoil were 0.23 ± 0.14, 37.63 ± 15.60, 25.83 ± 41.62, 88.38 ± 43.30, and 29.21 ± 12.41 mg kg(-1) (mean ± standard deviation), respectively. The heavy metals showed relatively higher concentrations on the borders among Zhejiang, Jiangsu, and Shanghai. In the meta-analysis, we selected 68 published studies related to heavy metal pollution in farmland topsoil of YRD from 2000 to the year (2014) when the field survey was conducted. The results show an increasing trend for Cd (p trend for Cu (p trend for Pb (p = 0.155), Zn (p = 0.746), and Ni (p = 0.305). The increasing rate of Cd from the meta-analysis is consistent with the rate (0.0013 mg kg(-1) year(-1)) derived from the mass balance calculation for Cd, where atmospheric deposition originated from intensive coal combustion is considered as the main source of Cd in the topsoil. The decreasing trend of Cu is likely due to largely reduced application of copper-based agrochemicals. Environmental regulation and soil remediation are needed to protect food safety and ecosystem from heavy metal pollution, especially Cd. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Sediment record of polycyclic aromatic hydrocarbons in the Liaohe River Delta wetland, Northeast China: Implications for regional population migration and economic development.

    Science.gov (United States)

    Ma, Chuanliang; Lin, Tian; Ye, Siyuan; Ding, Xigui; Li, Yuanyuan; Guo, Zhigang

    2017-03-01

    The polycyclic aromatic hydrocarbons (PAHs) of a (210)Pb-dated sediment core extracted from the Liaohe River Delta wetland were measured to reconstruct the sediment record of PAHs and its response to human activity for the past 300 years in Northeast China. The concentrations of the 16 U.S. Environmental Protection Agency priority PAHs (∑16PAHs) ranged from 46 to 1167 ng g(-1) in this sediment core. The concentrations of the 16 PAHs (especially 4- and 5+6-ring PAHs) after the 1980s (surface sediments 0-6 cm) were one or two orders of magnitudes higher than those of the down-core samples. The exponential growth of 4-ring and 5+6-ring PAH concentrations after the 1980s responded well to the increased energy consumption and number of civil vehicles resulting from the rapid economic development in China. Prior to 1950, relatively low levels of the 16 PAHs and a high proportion of 2+3-ring PAHs was indicative of biomass burning as the main source of the PAHs. A significant increase in the 2 + 3 ring PAH concentration from the 1860s-1920s was observed and could be attributed to a constant influx of population migration into Northeast China. It was suggested that the link between historical trend of PAHs and population or energy use involves two different economic stages. Typically, in an agricultural economy, the greater the population size, the greater the emission of PAHs from biomass burning, while in an industrial economy, the increase in sedimentary PAH concentrations is closely related to increasing energy consumption of fossil fuels.

  5. Impact of Sea Level Rise on Mangrove Ecosystem and its Dependent Fishing Communities in the Coastal Regions of Cauvery Delta: A Message for Policy Planners to Frame Suitable Antcipatory Adaptation Strategies

    Science.gov (United States)

    Amsad Ibrahim Khan, S. K.; Ramachandran, A.; Kandasamy, P.; Selvam, V.; Shanmugam, P.

    2014-12-01

    Coastal adaptation to sea-level rise (SLR) in the deltaic region is a multidimensional and complex process requiring informed decisions based on predicted impact and vulnerability assessment of SLR. Elevation plays a key role in determining the impact and vulnerability of coastal land areas to inundation from SLR. Highly accurate mapping of the elevation of the landscape is essential to identify low-lying coastal deltaic regions with valuable ecosystem like mangroves and its dependent human communities that are potentially at risk of inundation. It is difficult for policy planners and decision makers to identify suitable adaptation strategies without having information on the predicted impact and degree of vulnerability of coastal systems to SLR. Importantly, modeling and mapping will provide valuable input to climate change adaptation planning (NOAA 2010). Unfortunately, the comprehensive range of information that is typically required is seldom available and rarely in the possession of decision makers responsible for management of the deltaic and coastal zone (O'Regan, 1996). The present study seeks to provide insights on predicted impact of climate change induced SLR on mangrove ecosystem and its dependent human communities of Pichavaram mangroves, located at the Vellar-Coleroon estuarine region on the banks of Cauvery delta, Tamil Nadu, India. Based on real-time on-ground elevation measurement by DGPS (Differential Global Positioning System) survey and by using GIS portals, the study has identified about 597 ha of mangroves (one third of total mangrove regions) and about 9 fishing hamlets with 12,000 and more of human population that directly depends on this mangrove ecosystem for their livelihood are under threat of inundation to the predicted impact of 0.5m SLR. The present study is intended to showcase a method by providing reliable scientific information on predicted impact of SLR on mangroves and its dependent human communities to policy planner for

  6. Simulation analysis and verification of surface CO2 flux over Pearl River Delta, China%珠江三角洲近地层CO2通量模拟分析与评估验证

    Institute of Scientific and Technical Information of China (English)

    麦博儒; 安兴琴; 邓雪娇; 周凌晞; 王春林; 李菲; 黄建平; 陈玲; 尹淑娴

    2014-01-01

    Tracker-2010 (CT-2010) was used to analyze the seasonal and spatial distributions of net CO2 flux and CO2 sink characteristics of terrestrial ecosystems in the Pearl River Delta (PRD) region. Prior to doing simulations, the CT-2010 model was validated using in situ observations from the Panyu meteorological site (PYQXJ), the Dongguan site (DG), and the Ding Hushan site (DHS), which are representative of grassland, urban green space, and forest ecosystems in the PRD region, respectively. Net fluxes from the CT-2010model compared with observations from the three sites well. Hourly, daily, and diurnal residuals were less than 2.0 µmol/(m2·s) and correlation coefficients were greater than 0.60 (P<0.01). The CT-2010 model captured well the seasonal patterns of CO2fluxes over the PRD region. However, the magnitude of the simulated fluxes was generally greater than that of the observed fluxes. Annual residuals were 2.056, 0.964, and 2.100µmol/(m2·s) at the PYQXJ, DG, and DHS sites, respectively. From June 2004to May 2005, the mean surface net flux over the PRD region was 3.43µmol/(m2·s). In summer, fall, winter, and spring, mean surface net fluxes were 0.18, 0.51, 1.4, and 1.35 µmol/(m2·s), respectively. The mean terrestrial flux in the PRD was -6.5×10-3 PgC. The region during this time was dominated by crops (42.01%), grassland/shrubs (31.46%), and mixed (coniferous/broadleaf) forest (26.53%).

  7. El Partido (partido de la Revolución ¿Democrática? La dominación carismática en el PRD

    Directory of Open Access Journals (Sweden)

    Oscar Rivera Serafín

    2011-01-01

    Full Text Available El presente artículo analizará uno de los partidos políticos referentes en el sistema político mexicano: el Partido de la Revolución Democrática (PRD. El argumento a desarrollar es que dadas las características originarias de tal partido, la cohesión en los grupos políticos que lo componen sólo es alcanzada a través de un liderazgo carismático. Naturalmente, tal dependencia somete a dichos grupos a la inestabilidad inherente al ejercicio de la dominación carismática, por lo que sólo la aparición de un nuevo liderazgo les permite retomar la cohesión cuando el anterior declina.

  8. El Partido (partido) de la Revolución ¿Democrática? La dominación carismática en el PRD

    OpenAIRE

    Oscar Rivera Serafín

    2011-01-01

    El presente artículo analizará uno de los partidos políticos referentes en el sistema político mexicano: el Partido de la Revolución Democrática (PRD). El argumento a desarrollar es que dadas las características originarias de tal partido, la cohesión en los grupos políticos que lo componen sólo es alcanzada a través de un liderazgo carismático. Naturalmente, tal dependencia somete a dichos grupos a la inestabilidad inherente al ejercicio de la dominación carismática, por lo que sólo la apari...

  9. A measurement of rural-urban income disparity in Yangtze River delta region%长江三角洲地区城乡收入差距测度

    Institute of Scientific and Technical Information of China (English)

    尹帅

    2015-01-01

    基于GE指数相关理论,测度了长江三角洲的城乡收入差距,测算和分析各种收入来源对城乡之间收入差距的影响度,得出了经营性收入对城乡收入差距的贡献率最大、工资性收入其次、财产性收入和转移性收入贡献率最小等结论。%The eastern area of China,with its economic power in Yangtze River delta region,always plays a vital role in the national macro-economy. The regional booming economy,however,has brought another potential obstacle to the surface—the income gap between the urban and rural areas. Based on the GE in-dex and the related theories,this paper conducts first a measurement of the rural-urban income disparity in this region and then an analysis of the influence of various sources of income on this gap. The result shows that the operational income,followed by wage income,has made the greatest contribution,while the property income and transfer income pose as the least concerned sources.

  10. Impact of urban expansion on regional temperature change in the Yangtze River Delta%长江三角洲城市带扩展对区域温度变化的影响

    Institute of Scientific and Technical Information of China (English)

    杜银; 谢志清; 曾燕; 施雅风; 武金岗

    2007-01-01

    Based on non-radiance-calibrated DMSP/OLS nighttime light imagery from 1992 to 2003, urban land area statistical data, meteorological data and land surface temperature data retrieved by MODIS and NOAA/AVHRR data, the influence of urbanization on regional climatic trend of temperature in the Yangtze River Delta (YRD) was analyzed. Conclusions are as follows: 1) There is a significant urbanization process from 1992 to 2003 in the YRD. Four city clusters of Nanjing-Zhenjiang-Yangzhou, Suzhou-Wuxi-Changzhou, Shanghai and Hangzhou Bay form a zigzag city belt. The increase rate of annual mean air temperature in city-belt is 0.28-0.44℃/10a from 1991 to 2005, which is far larger than that of non-city-belt. 2) The urban heat island (UHI) effect on regional mean air temperature in different seasons is summer>autumn>spring>winter. 3) The UHI intensity and the urban total population logarithm are creditably correlated. 4) The UHI effect made the regional annual mean air temperature increased 0.072℃ from 1961 to 2005, of which 0.047℃ from 1991 to 2005, and the annual maximum air temperature increased 0.162℃, of which 0.083℃ from 1991 to 2005. All these indicating that the urban expansion in the YRD from 1991 to 2005 may be regarded as a serious climate signal.

  11. On the width of N-Delta and Delta-Delta states

    CERN Document Server

    Niskanen, J A

    2016-01-01

    It is seen by a coupled-channel calculation that in the two-baryon N-Delta or Delta-Delta system the width of the state is greatly diminished due to the relative kinetic energy of the two baryons, since the internal energy of the particles, available for pionic decay, is smaller. A similar state dependent effect arises from the centrifugal barrier in N-Delta or Delta-Delta systems with non-zero orbital angular momentum. The double-Delta width can become even smaller than the free width of a single Delta. This has some bearing to the interpretation of the d'(2380) resonance recently discovered at COSY.

  12. geomorphology_delta

    Data.gov (United States)

    California Department of Resources — Surficial geology of the Delta area of California by Brian Atwater of the U.S. Geological Survey. Source maps are from the USGS publication MF-1401. This digital...

  13. Deriving Spatio-Temporal Development of Ground Subsidence Due to Subway Construction and Operation in Delta Regions with PS-InSAR Data: A Case Study in Guangzhou, China

    Directory of Open Access Journals (Sweden)

    Huiqiang Wang

    2017-09-01

    Full Text Available Subways have been an important method for relieving traffic pressures in urban areas, but ground subsidence, during construction and operation, can be a serious problem as it may affect the safety of its operation and that of the surrounding buildings. Thus, conducting long-term ground deformation monitoring and modeling for subway networks are essential. Compared with traditional geodetic methods, the Persistent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR technique offers wider coverage and denser measurements along subway lines. In this study, we mapped the surface deformation of the Guangzhou subway network with Advanced Synthetic Aperture Radar (ASAR and Phased Array Type L-band Synthetic Aperture Radar (PALSAR data using the Interferometric Point Target Analysis (IPTA technique. The results indicate that newly excavated tunnels have regional subsidence with an average rate of more than 8 mm/year, as found on Lines Two, Three, Six, and GuangFo (GF. Furthermore, we determined the spatio-temporal subsidence behavior of subways with PALSAR in delta areas using Peck’s formula and the logistic time model. We estimated the tunneling-related parameters in soft soil areas, which had not been previously explored. We examined a section of line GF, as an example, to estimate the ground settlement trough development. The results showed the maximum settlement increased from −5.2 mm to −23.6 mm and its ground loss ratio ranged from 1.5–8.7% between 13 July 2008 and 19 January 2011. In addition, we found that the tunnels in line GF will become stable after a period of about 2300 days in peak subsidence areas. The results show that the proposed approach can help explain the dynamic ground subsidence along a metro line. This study can provide references for urban subway projects in delta areas, and for the risk assessment of nearby buildings and underground pipelines along metro lines.

  14. Delta-Reliability

    OpenAIRE

    Eugster, P.; Guerraoui, R.; Kouznetsov, P.

    2001-01-01

    This paper presents a new, non-binary measure of the reliability of broadcast algorithms, called Delta-Reliability. This measure quantifies the reliability of practical broadcast algorithms that, on the one hand, were devised with some form of reliability in mind, but, on the other hand, are not considered reliable according to the ``traditional'' notion of broadcast reliability [HT94]. Our specification of Delta-Reliability suggests a further step towards bridging the gap between theory and...

  15. Air Temperature Variation in Recent 40 Years over Pearl River Delta Region%珠三角地区近40年的气温变化特征分析

    Institute of Scientific and Technical Information of China (English)

    封静; 潘安定; 李冰

    2011-01-01

    主要运用气候倾向率和三阶多项式曲线拟合的方法,对珠三角的25个气象站1965—2007年近43年来的年均温和月平均气温观测数据进行了倾向、趋势分析,并对25个气象站气温的空间分布进行统计分析。研究结果表明:珠三角地区气温年际变化的趋势性明显,季节变化表现为夏季和秋季的趋势性变化显著:珠三角地区年平均气温的空间分布可以看到,珠三角的南部地区气温明显高于北部地区,南部和北部的最高和最低温度之差达到2.6℃:珠三角地区的春季、夏季、秋季的温度空间分布的差异不大,冬季气温的南北差异明显,最大温差为2.9℃。%In order to investigate the characteristics of air temperature variation over the Pearl River Delta Region, the annual average temperature and mean monthly temperatures observation data from 25 meteoro- logical stations through 1965-2007 the past 40 years are analyzed by using the methods of climatic trend rate, third-order polynomial curve and 25 meteorological stations of spatial distribution of temperature were statistically analyzed. The results show that the trend of temperature interannual variability is obvious and the trend of the summer and fall change significantly in Pearl River Delta Region. The annual average tem- perature of southern region significantly is higher than that of northern areas, and the difference between maximum temperature of the south and minimum temperature of the north reach 2.6℃ .Temperature differ- ence of the spatial distribution of spring, summer, fall is not significant, and temperature difference of winter between maximum temperature of the south and minimum temperature of the north reach 2.9 ℃.

  16. Homogenization Analysis of Airports in China Yangtze River Delta Region%区域机场同质化发展特征分析——以长三角地区机场群为例

    Institute of Scientific and Technical Information of China (English)

    蒋永雷; 杨忠振; 王璐; 邹汶倩

    2013-01-01

    With integrate endow proportion method, this paper build the improved similarity coefficient to measure the homogenization degree of airports in Yangtze River Delta Region. In addition, a network was built with the comprehensive similarity coefficient, the indexes of complex network theory was employed to analyze the construct characteristic of airport homogenization network. Key results show that the airport homogenization of Yangtze River Delta Region is outstanding; the homogenization degree of regional hub airports are the most serious because of their strong radiant intensity and concentrated location; due to the similar urban economic structure, the homogenization of other neighboring airports are inevitable. Finally, the policy recommendations like Integration and differentiation strategy were proposed.%通过构建测量区域机场同质化发展的改进相似系数,运用综合赋权评价法,对长三角地区机场发展的同质化水平进行测算,并以综合相似系数构建机场同质化网络,采用复杂网络结构方法对机场同质化网络进行分析.结果表明:长三角经济核心圈机场存在明显的同质化水平;枢纽型机场由于机场辐射能力强且分布密集而同质化水平最为明显;核心边缘的地区型机场由于城市经济规模小且距离较近,机场为了进一步发展而产生趋同化;其他地区型机场则由于长三角地区内城市经济结构的相似,邻近机场间的服务呈现趋同化.最后,针对长三角地区机场同质化发展特征提出区域机场一体化和差异化发展的政策建议.

  17. Study on Strategy for Establishing Green Logistics System for Zhujiang River Delta Region%珠三角绿色物流体系构建策略研究

    Institute of Scientific and Technical Information of China (English)

    许笑平

    2014-01-01

    在界定绿色物流内涵的基础上,较系统地分析了珠三角绿色物流发展中存在的问题,如区域综合运输体系不健全、绿色物流技术落后等;从构建绿色物流政策体系、综合运输体系、绿色物流技术创新体系等四个方面提出构建珠三角绿色物流体系的策略,以期有效地推进珠三角绿色物流的发展进程。%In this paper, on the basis of a definition of the connotation of green logistics, we systematically analyzed the problems in the development of the green logistics industry in the Zhujiang River Delta region and then from four aspects, proposed the strategy to build and enhance the green logistics system of the region.

  18. 珠三角区域经济综合评价模型的构建与应用%An Evaluation Model for the Pearl River Delta Regional Economics

    Institute of Scientific and Technical Information of China (English)

    曹建新; 谭培洪

    2011-01-01

    Integrating the ideas of Diamond and Groundings Enterprises Markets (GEM) models, a novel model to evaluate the economic level of a regional economics is developed, which overcomes the disadvantages of the existing evaluation models. With the framework of the model, analytic hierarchy process (AHP) method is adopted to determine the weight of each evaluation index. The proposed model is used to evaluate the economic development of the Pearl River Delta Region.%在分析当前区域经济评价体系弊端的基础上,结合"钻石模型"和GEM模型的研究成果,设计一套区域经济评价体系模型,运用层次分析法(AHP)确定评价指标体系模型中各指标权重,并以珠江三角洲区域经济为实例,得出珠三角经济综合评价并提出珠三角区域经济发展建议.

  19. The Impact of Regional Differences of Tourism Resources on Tourism Economy in Yangtze River Delta%长江三角洲旅游资源地区差异对旅游经济的影响研究

    Institute of Scientific and Technical Information of China (English)

    方琰; 卞显红

    2015-01-01

    以长江三角洲为研究区域,采用丰度公式、德尔菲法、加权求和法、聚类分析法等对旅游资源的数量、质量及综合禀赋进行全面探究,运用相关系数法定量探析2003-2011年长江三角洲旅游资源地区差异对旅游经济的动态影响。研究结果表明:(1)长江三角洲各地区旅游资源数量、质量及综合禀赋对旅游收入均有影响,其中旅游资源禀赋对旅游收入的影响最大,旅游资源数量的影响最小;(2)长江三角洲各地区的旅游经济发展水平差异形成的主导因子是旅游资源禀赋差异,同时国内旅游经济发展水平与旅游资源禀赋的相关性高于入境旅游经济发展水平;(3)长江三角洲各地区旅游资源禀赋与旅游经济发展速度存在一定的同步-错位关系,同时旅游资源禀赋与入境旅游经济发展速度的同步-错位关系更为明显。%Taking Yangtze River Delta as the study area,the paper used the abundance formula,delphi,weighted sum and clus-ter analysis method to analyze the difference of tourism resources.What’s more,the impact of regional differences of tourism re-sources on tourism economy from 2003 to 201 1 was analyzed by using the correlation coefficient.The results are as following:(1) The quantity,quality and abundance of tourism resources have influenced the tourism income in Yangtze River Delta.,and the tourism income is mostly affected by abundance of tourism resources,while the quantity of tourism resources does least.(2)The abundance of tourism resources is one of the main causes of difference of tourism economy in Yangtze River Delta,and the corre-lation between abundance of tourism resources and domestic tourism economy is more significant than inbound tourism economy. (3)There is an asynchronous relationship between abundance of tourism resources and tourism economic growth rate in Yangtze River Delta,and the asynchronous relationship between abundance of tourism

  20. Sources of ambient volatile organic compounds and their contributions to photochemical ozone formation at a site in the Pearl River Delta, southern China

    Energy Technology Data Exchange (ETDEWEB)

    Ling, Z.H. [Air Quality Studies, Department of Civil and Structural Engineering, Hong Kong Polytechnic University (Hong Kong); Guo, H., E-mail: ceguohai@polyu.edu.hk [Air Quality Studies, Department of Civil and Structural Engineering, Hong Kong Polytechnic University (Hong Kong); Cheng, H.R.; Yu, Y.F. [Air Quality Studies, Department of Civil and Structural Engineering, Hong Kong Polytechnic University (Hong Kong)

    2011-10-15

    The Positive Matrix Factorization (PMF) receptor model and the Observation Based Model (OBM) were combined to analyze volatile organic compound (VOC) data collected at a suburban site (WQS) in the PRD region. The purposes are to estimate the VOC source apportionment and investigate the contributions of these sources and species of these sources to the O{sub 3} formation in PRD. Ten VOC sources were identified. We further applied the PMF-extracted concentrations of these 10 sources into the OBM and found 'solvent usage 1', 'diesel vehicular emissions' and 'biomass/biofuel burning' contributed most to the O{sub 3} formation at WQS. Among these three sources, higher Relative Incremental Reactivity (RIR)-weighted values of ethene, toluene and m/p-xylene indicated that they were mainly responsible for local O{sub 3} formation in the region. Sensitivity analysis revealed that the sources of 'diesel vehicular emissions', 'biomass/biofuel burning' and 'solvent usage 1' had low uncertainties whereas 'gasoline evaporation' showed the highest uncertainty. - Highlights: > Ten sources of VOCs were identified by the PMF receptor model in the PRD region. > In terms of mass percentage, solvent was the largest contributor, followed by vehicle emissions. > Solvent, diesel vehicles and biomass/biofuel burning were the top three VOC contributors to O{sub 3} formation. > Among these three sources, ethene, toluene and m/p-xylene were responsible for O{sub 3} formation. > Biomass/biofuel burning had low uncertainty whereas gasoline evaporation showed high uncertainty. - Solvent usage, diesel vehicular emissions and biomass/biofuel burning were the major contributors to the photochemical O{sub 3} formation in the PRD region.

  1. General, kappa, delta and mu opioid receptor antagonists mediate feeding elicited by the GABA-B agonist baclofen in the ventral tegmental area and nucleus accumbens shell in rats: reciprocal and regional interactions.

    Science.gov (United States)

    Miner, Patricia; Shimonova, Lyudmila; Khaimov, Arthur; Borukhova, Yaffa; Ilyayeva, Ester; Ranaldi, Robert; Bodnar, Richard J

    2012-03-14

    Food intake is significantly increased following administration of agonists of GABA and opioid receptors into the nucleus accumbens shell (NACs) and ventral tegmental area (VTA). GABA-A or GABA-B receptor antagonist pretreatment within the VTA or NACs differentially affects mu-opioid agonist-induced feeding elicited from the same site. Correspondingly, general or selective opioid receptor antagonist pretreatment within the VTA or NACs differentially affects GABA agonist-induced feeding elicited from the same site. Regional interactions have been evaluated in feeding studies by administering antagonists in one site prior to agonist administration in a second site. Thus, opioid antagonist-opioid agonist and GABA antagonist-GABA agonist feeding interactions have been identified between the VTA and NACs. However, pretreatment with GABA-A or GABA-B receptor antagonists in the VTA failed to affect mu opioid agonist-induced feeding elicited from the NACs, and correspondingly, these antagonists administered in the NACs failed to affect mu opioid-induced feeding elicited from the VTA. To evaluate whether regional and reciprocal VTA and NACs feeding interactions occur for opioid receptor modulation of GABA agonist-mediated feeding, the present study examined whether feeding elicited by the GABA-B agonist, baclofen microinjected into the NACs was dose-dependently blocked by pretreatment with general (naltrexone: NTX), mu (beta-funaltrexamine: BFNA), kappa (nor-binaltorphamine: NBNI) or delta (naltrindole: NTI) opioid antagonists in the VTA, and correspondingly, whether VTA baclofen-induced feeding was dose-dependently blocked by NACs pretreatment with NTX, BFNA, NBNI or NTI in rats. Bilateral pairs of cannulae aimed at the VTA and NACs were stereotaxically implanted in rats, and their food intakes were assessed following vehicle and baclofen (200 ng) in each site. Baclofen produced similar magnitudes of increased food intake following VTA and NACs treatment. Baclofen

  2. 过去150年长三角地区的春季物候变化%Changes of Spring Phenodate in Yangtze River Delta Region in the Past 150 Years

    Institute of Scientific and Technical Information of China (English)

    郑景云; 葛全胜; 郝志新; 仲舒颖; 马翔; 张学珍

    2012-01-01

    利用中国历史日记中的长三角地区春季物候记录,重建了该地区1834年以来的春季物候期变化序列,同时结合气温观测资料分析了该序列对温度变化的指示意义.主要结论有:(1) 1834-1893年,长三角地区春季物候在波动中逐渐推迟,但19世纪末起突然出现大幅提前;1900-1990年以年代际波动为主要特征,1990-2010年又再次出现大幅提前;1834年以来,该地区春季物候最迟的年份为1893年,最早的年份为2007年,分别较1977-1996年平均推迟27天和提早17天.(2)长三角地区的春季物候期变化与该地区上年12月-当年3月及当年1-3月气温变化的相关系数分别超过-0.75、-0.80,可很好地指示该地区的冬季与初春(特别是1-3月)气温变化;这为进一步集成多种代用资料重建历史时期的中国温度变化提供了重要数据基础和依据.%Based on phenological records extracted from Chinese historical dairies, the series of spring phenodate in the Yangtze River Delta region of China since 1834 is reconstructed. Together with the temperature and phenology observation data, the interpretation of the phenodate variation to temperature change is also analyzed. The results are shown as follows. (1) Spring phenology in the Yangtze River Delta region is gradually delayed during 1834-1893 and greatly advances after 1893; and exhibits inter-decadal fluctuation during 1900-1990 and greatly advances after 1990. The latest year of the spring phenodate is delayed by 27 days and occurs in 1893, while the earliest year is advanced by 17 days and occurs in 2007. (2) Correlation coefficient between spring phenodate in the Yangtze River Delta region and temperature (previous December to March and January to March) is higher significant up to the level at 99.9% with the value over -0.75 and -0.80, respectively. The variation of spring phenodate well indicates the change of temperature from previous winter to early spring, especially

  3. An annotated list of Fishes from the Niger Delta

    NARCIS (Netherlands)

    Boeseman, M.

    1963-01-01

    At the end of November 1960, the Leiden Museum received an interesting collection of animals, mostly fishes, from the Niger delta. All specimens were collected by Mr. H. J. G. Beets, at the time employed by Shell B.P. — Delta Investigations, during the period May to August 1960, and in the region

  4. Emerging leadership from communities in the Lower Mississippi Delta (LMD)

    Science.gov (United States)

    The Delta NIRI (Nutrition Intervention Research Initiative) team has conducted several research studies in the Lower Mississippi Delta (LMD) region employing the community-based participatory research (CBPR) model. Our collaborative work in the LMD focuses on interventions conducted in each of our c...

  5. Changes in regional meteorology induced by anthropogenic heat and their impacts on air quality in South China

    Science.gov (United States)

    Xie, Min; Zhu, Kuanguang; Wang, Tijian; Feng, Wen; Gao, Da; Li, Mengmeng; Li, Shu; Zhuang, Bingliang; Han, Yong; Chen, Pulong; Liao, Jingbiao

    2016-12-01

    Anthropogenic heat (AH) emissions from human activities can change the urban circulation and thereby affect the air pollution in and around cities. Based on statistic data, the spatial distribution of AH flux in South China is estimated. With the aid of the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem), in which the AH parameterization is developed to incorporate the gridded AH emissions with temporal variation, simulations for January and July in 2014 are performed over South China. By analyzing the differences between the simulations with and without adding AH, the impact of AH on regional meteorology and air quality is quantified. The results show that the regional annual mean AH fluxes over South China are only 0.87 W m-2, but the values for the urban areas of the Pearl River Delta (PRD) region can be close to 60 W m-2. These AH emissions can significantly change the urban heat island and urban-breeze circulations in big cities. In the PRD city cluster, 2 m air temperature rises by 1.1° in January and over 0.5° in July, the planetary boundary layer height (PBLH) increases by 120 m in January and 90 m in July, 10 m wind speed is intensified to over 0.35 m s-1 in January and 0.3 m s-1 in July, and accumulative precipitation is enhanced by 20-40 % in July. These changes in meteorological conditions can significantly impact the spatial and vertical distributions of air pollutants. Due to the increases in PBLH, surface wind speed and upward vertical movement, the concentrations of primary air pollutants decrease near the surface and increase in the upper levels. But the vertical changes in O3 concentrations show the different patterns in different seasons. The surface O3 concentrations in big cities increase with maximum values of over 2.5 ppb in January, while O3 is reduced at the lower layers and increases at the upper layers above some megacities in July. This phenomenon can be attributed to the fact that chemical effects can play a

  6. Inclusive (p,p') cross sections and analyzing powers for /sup 1/H and /sup 12/C in the delta region

    Energy Technology Data Exchange (ETDEWEB)

    McGill, J.A.; Glashausser, C.; Jones, K.; Nanda, S.K. (Rutgers - the State Univ., New Brunswick, NJ (USA)); Barlett, M.; Fergerson, R.; Marshall, J.A.; Milner, E.C.; Hoffmann, G.W. (Texas Univ., Austin (USA))

    1984-01-12

    Cross sections and analyzing powers have been measured at 800 MeV for inclusive (p,p') reactions on /sup 1/H and /sup 12/C in the 300 MeV excitation region. The data for /sup 1/H and /sup 12/C are qualitatively similar, but differ in detail. A Born approximation model reproduces the cross sections for p + p scattering, but fails to fit the Asub(y) data. Further, while a plane wave impulse approximation calculation reproduces the general features of the /sup 12/C(p,p') cross sections, significant details are not accounted for.

  7. First measurement of target and double spin asymmetries for polarized e- polarized p --> e p pi0 in the nucleon resonance region above the Delta(1232)

    CERN Document Server

    Biselli, A S; Amaryan, M J; Asryan, G; Avakian, H; Bagdasaryan, H; Baillie, N; Ball, J P; Baltzell, N A; Battaglieri, M; Bedlinskiy, I; Bellis, M; Benmouna, N; Berman, B L; Blaszczyk, L; Bookwalter, C; Boiarinov, S; Bosted, P; Bradford, R; Branford, D; Briscoe, W J; Brooks, W K; Bültmann, S; Butuceanu, C; Calarco, J R; Careccia, S L; Carman, D S; Casey, L; Chen, S; Cheng, L; Cole, P L; Collins, P; Coltharp, P; Crabb, D; Credé, V; Dale, D; Dashyan, N; De Masi, R; De Vita, R; De Sanctis, E; Degtyarenko, P V; Deur, A; Dhamija, S; Dickson, R; Djalali, C; Dodge, G E; Doughty, D; Dugger, M; Dzyubak, O P; Egiyan, H; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Feuerbach, R; Fersch, R; Forest, T A; Fradi, A; Garçon, M; Gavalian, G; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gohn, W; Gothe, R W; Graham, L; Griffioen, K A; Guidal, M; Guler, N; Guo, L; Gyurjyan, V; Hafidi, K; Hakobyan, H; Hanretty, C; Hassall, N; Hicks, K; Hleiqawi, I; Holtrop, M; Hyde-Wright, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Ito, M M; Jenkins, D; Jo, H S; Johnstone, J R; Joo, K; Jüngst, H G; Kalantarians, N; Keller, D; Kellie, J D; Khandaker, M; Kim, W; Klein, A; Klein, F J; Kossov, M; Krahn, Z; Kubarovski, V; Kühn, J; Kuhn, S E; Kuleshov, S V; Kuznetsov, V; Lachniet, J; Laget, J M; Langheinrich, J; Lawrence, D; Livingston, K; Lu, H Y; MacCormick, M; Markov, N; Mattione, P; McKinnon, B; McNabb, J W C; Mecking, B A; Mestayer, M D; Meyer, C A; Mibe, T; Mikhailov, K; Mirazita, M; Mokeev, V; Moreno, B; Moriya, K; Morrow, S A; Moteabbed, M; Munevar, E; Mutchler, G S; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niroula, M R; Niyazov, R A; Nozar, M; Osipenko, M; Ostrovidov, A I; Park, K; Park, S; Pasyuk, E; Paterson, C; Anefalos Pereira, S; Pierce, J; Pivnyuk, N; Pogorelko, O; Pozdniakov, S; Price, J W; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Ripani, M; Ritchie, B G; Rosner, G; Rossi, P; Sabati, F; Saini, M S; Salamanca, J; Salgado, C; Santoro, J P; Sapunenko, V; Schott, D; Schumacher, R A; Serov, V S; Sharabyan, Yu G; Sharov, D; Shvedunov, N V; Smith, E S; Sober, D I; Sokhan, D; Stavinsky, A; Stepanyan, S S; Stepanyan, S; Stokes, B E; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Tedeschi, D J; Tkabladze, A; Tkachenko, S; Todor, L; Ungaro, M; Vineyard, M F; Vlassov, A V; Watts, D P; Weinstein, L B; Weygand, D P; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Yurov, M; Zana, L; Zhang, J; Zhao, B; Zhao, Z W

    2008-01-01

    The exclusive channel polarized proton(polarized e,e prime p)pi0 was studied in the first and second nucleon resonance regions in the Q2 range from 0.187 to 0.770 GeV2 at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). Longitudinal target and beam-target asymmetries were extracted over a large range of center-of-mass angles of the pi0 and compared to the unitary isobar model MAID, the dynamic model by Sato and Lee, and the dynamic model DMT. A strong sensitivity to individual models was observed, in particular for the target asymmetry and in the higher invariant mass region. This data set, once included in the global fits of the above models, is expected to place strong constraints on the electrocoupling amplitudes A_{1/2} and S_{1/2} for the Roper resonance N(1400)P11, and the N(1535)S11 and N(1520)D13 states.

  8. First measurement of target and double spin asymmetries for polarized e- polarized p --> e p pi0 in the nucleon resonance region above the Delta(1232)

    Energy Technology Data Exchange (ETDEWEB)

    Biselli, Angela; Burkert, Volker; Amaryan, Moscov; Amaryan, Moskov; Asryan, Gegham; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Bedlinskiy, Ivan; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Blaszczyk, Lukasz; Bookwalter, Craig; Boyarinov, Sergey; Bosted, Peter; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Crabb, Donald; Crede, Volker; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Deur, Alexandre; Dhamija, Seema; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Doughty, David; Dugger, Michael; Dzyubak, Oleksandr; Egiyan, Hovanes; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Feuerbach, Robert; Fersch, Robert; Forest, Tony; Fradi, Ahmed; Garcon, Michel; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guidal, Michel; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hassall, Neil; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahb