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Li Q.,Beijing Normal University | Cheng H.,Beijing Normal University | Zhou T.,Beijing Normal University | Lin C.,Beijing Normal University | Guo S.,South China Institute of Environmental Sciences
Atmospheric Environment | Year: 2012

Estimates of atmospheric emissions of lead from anthropogenic sources in China from 1990 to 2009 are presented with the information on emissions of both total lead and its spatial distribution in regions. The total emissions during the period 1990-2009 are nearly 200 000 tons. Motor vehicle gasoline combustion was the largest source of anthropogenic emissions. The estimated release of 117 800 t of lead represented 60% of the total emissions. Substantial decline occurred in 2001, when the total emissions were about 81% less than the 2000 value. The reduced lead content of motor vehicle gasoline is the primary reason for the decreased in lead emissions in 2001. After leaded gasoline was phased out, coal combustion became the principal source of emissions. Based on data on emissions from 2005 through 2009, the emissions are concentrated in eastern and central China due to the high level of coal consumption and non-ferrous metal smelting. The five provinces with the largest amounts of lead emissions are Shandong, Hebei, Shanxi, Henan and Jiangsu. These five regions produced nearly 40% of the total. © 2012 Elsevier Ltd.


Wang Z.,Peking University | Yang Y.,Peking University | He T.,South China Institute of Environmental Sciences | Xie S.,Peking University
Applied Microbiology and Biotechnology | Year: 2015

Biodegradation by autochthonous microbial community is an important way to clean up nonylphenol (NP) from contaminated river sediment. Knowledge of sediment microbial community can aid in our understanding of biological processes related to NP degradation. However, the change in sediment microbial community associated with NP biodegradation remains unclear. The present study investigated the shift in bacterial community structure and NP-degrading gene abundance in response to NP attenuation in river sediment. Sediment microcosms with different levels of 4-NP (0, 100, or 300 μg/g) were constructed. A nearly complete attenuation of NP occurred in the microcosm with 100 μg/g NP after 9 days’ incubation, while a residual NP rate of 8.1 % was observed in the microcosm with 300 μg/g NP after 22 days’ incubation. Illumina MiSeq sequencing analysis indicated that Gammaproteobacteria, Alphaproteobacteria, and Bacteroidetes predominated in NP-degrading river sediment. Sediment bacterial community structure varied significantly during NP biodegradation and subsequent incubation, which was affected by the level of added NP. The n-alkane biodegradation (alkB) gene abundance showed a significant variation in each NP-amended microcosm (100 or 300 μg/g), while a significant increase in the single component monooxygenase (sMO) gene abundance only occurred in the microcosm spiked with 300 μg/g NP. This study can provide some new insights toward NP-degrading microbial ecology in the environment. © 2014, Springer-Verlag Berlin Heidelberg.


Guo Q.,South China Institute of Environmental Sciences | Wan R.,Peking University | Xie S.,Peking University
Environmental Science and Pollution Research | Year: 2014

The objective of this study was to investigate the impact of exogenous urea nitrogen on ammonia-oxidizing bacteria (AOB) and other soil bacterial communities in soil bioaugmented for simazine remediation. The previously isolated simazine-degrading Arthrobacter sp. strain SD1 was used to degrade the herbicide. The effect of urea on the simazine degradation capacity of the soil bioaugmented with Arthrobacter strain SD1 was assessed using quantitative PCR targeting the s-triazine-degrading trzN and atzC genes. Structures of bacterial and AOB communities were characterized using terminal restriction fragment length polymorphism. Urea fertilizer could affect simazine biodegradation and decreased the proportion of its trzN and atzC genes in soil augmented with Arthrobacter strain SD1. Bioaugmentation process could significantly alter the structures of both bacterial and AOB communities, which were strongly affected by urea amendment, depending on the dosage. This study could provide some new insights towards s-triazine bioremediation and microbial ecology in a bioaugmented system. However, further studies are necessary in order to elucidate the impact of different types and levels of nitrogen sources on s-triazine-degraders and bacterial and AOB communities in bioaugmented soil. © 2013 Springer-Verlag Berlin Heidelberg.


Zhang R.,CAS Institute of Atmospheric Physics | Jing J.,CAS Institute of Atmospheric Physics | Jing J.,Meteorological Observation Center | Tao J.,South China Institute of Environmental Sciences | And 8 more authors.
Atmospheric Chemistry and Physics | Year: 2013

In this study, 121 daily PM2.5 (aerosol particle with aerodynamic diameter less than 2.5 μm) samples were collected from an urban site in Beijing in four months between April 2009 and January 2010 representing the four seasons. The samples were determined for various compositions, including elements, ions, and organic/elemental carbon. Various approaches, such as chemical mass balance, positive matrix factorization (PMF), trajectory clustering, and potential source contribution function (PSCF), were employed for characterizing aerosol speciation, identifying likely sources, and apportioning contributions from each likely source. Our results have shown distinctive seasonality for various aerosol speciations associated with PM2.5 in Beijing. Soil dust waxes in the spring and wanes in the summer. Regarding the secondary aerosol components, inorganic and organic species may behave in different manners. The former preferentially forms in the hot and humid summer via photochemical reactions, although their precursor gases, such as SO2 and NOx, are emitted much more in winter. The latter seems to favorably form in the cold and dry winter. Synoptic meteorological and climate conditions can overwhelm the emission pattern in the formation of secondary aerosols. The PMF model identified six main sources: soil dust, coal combustion, biomass burning, traffic and waste incineration emission, industrial pollution, and secondary inorganic aerosol. Each of these sources has an annual mean contribution of 16, 14, 13, 3, 28, and 26%, respectively, to PM2.5. However, the relative contributions of these identified sources significantly vary with changing seasons. The results of trajectory clustering and the PSCF method demonstrated that regional sources could be crucial contributors to PM pollution in Beijing. In conclusion, we have unraveled some complex aspects of the pollution sources and formation processes of PM2.5 in Beijing. To our knowledge, this is the first systematic study that comprehensively explores the chemical characterizations and source apportionments of PM2.5 aerosol speciation in Beijing by applying multiple approaches based on a completely seasonal perspective. © Author(s) 2013.


Ng C.N.,University of Hong Kong | Xie Y.J.,University of Hong Kong | Yu X.J.,University of Hong Kong | Yu X.J.,South China Institute of Environmental Sciences
Applied Geography | Year: 2013

This paper examines the integration of landscape connectivity and ecosystem services. It is based on the assumption that if a habitat within a landscape has a more significant role in connecting with other habitats, it would have a higher ecosystem services value for biodiversity conservation. The Shenzhen River watershed, a cross-border region shared by the city of Shenzhen and the Hong Kong Special Administrative Region in China, was used as a case study. An area-based functional connectivity index, known as the possibility of connectivity (PC), was implemented to examine the temporal and spatial dynamics of the value of ecosystem services for biodiversity conservation over the period from 1988 to 2008. To evaluate the effectiveness of the PC index, a comparison was made between the conventional assessment method for ecosystem services and the proposed method. Results suggest that our proposed method can identify significant reduction of ecosystem services that was not only due to the decrease of habitat size, but also caused by the damage of connectivity among habitat patches. Also, it can identify sites which should have a high priority in restoring the ecosystem services for biodiversity conservation. In conclusion, this study provides a way to consider landscape connectivity in the evaluation of ecosystem services which is essential for landscape planning and nature conservation. © 2013 Elsevier Ltd.


Wu L.,CAS Guangzhou Institute of Energy Conversion | Zhang Y.,CAS Guangzhou Institute of Energy Conversion | Li X.,CAS Guangzhou Institute of Energy Conversion | Cen C.,South China Institute of Environmental Sciences
Physical Chemistry Chemical Physics | Year: 2014

CdS nanorod arrays were grown on fluorine-doped tin oxide glass substrates via a hydrothermal process and subsequently coated with a TiO2 nanolayer via a vacuum dip-coating process to fabricate a one-dimensional array structured photocatalyst. The TiO2 nanolayer improved the photocatalytic efficiency of CdS nanorod arrays for the degradation of methylene blue due to the effective separation of the electron-hole pairs, and the photocorrosion of CdS nanorod arrays was successfully inhibited. This journal is © the Partner Organisations 2014.


Wu S.,South China Normal University | Fang J.,South China Normal University | Xu W.,South China Normal University | Cen C.,South China Institute of Environmental Sciences
Journal of Molecular Catalysis A: Chemical | Year: 2013

Herein, we reported an ultrasonic-assisted synthesis of bismuth-modified rectorite with high visible light-induced photocatalytic activity. The as-synthesized samples were characterized by XRD, FT-IR, FESEM, TEM, BET, and UV-vis DRS techniques. Two toxic and nonbiodegradable organic compounds, Rhodamine B (RhB) and 2,4-dichlorophenol (DCP), were chosen as the target pollutants to characterize the adsorption performance and photocatalytic activity. The results showed that the prepared samples possessed strong adsorbility and exhibited high efficient photocatalytic activity under visible light irradiation. The excellent photocatalytic activity of bismuth-modified rectorite was ascribed to the strong adsorption ability, the interconnected heterojunction of Bi2O3 and Bi5O 7NO3, and the produced OH. Finally, the possible mechanism was presented. © 2013 Elsevier B.V.


Cai M.,South China Institute of Environmental Sciences | Li K.,South China Institute of Environmental Sciences
Procedia Engineering | Year: 2011

In attempt to highlight the socio-economic importance and the impact of industrialization and urbanization activities on marine ecosystem, the total economic value of marine ecosystem adjacent to Pearl River estuary of China and its economic losses from current pollution were calculated in this paper. It indicated that total economic value of the studied marine ecosystem amounted to 3.05×10 4 million US$ annually, among which the value of industrial utilization was the most important. The current pollution situation caused an economic loss of 5.04×10 3 million US$ annually, which accounted for 16.5%of the total economic value of the marine ecosystem. Further assessment on pollution damages to marine ecosystem showed that ecosystem functions such as regulation, purification, research and fishery were impaired significantly. © 2010 Published by Elsevier Ltd.


Zhang G.,South China University of Technology | Hai J.,South China Institute of Environmental Sciences | Cheng J.,South China University of Technology
Waste Management | Year: 2012

The input and output samples from existing large-scale municipal solid waste incinerator (MSWI) were collected and analyzed for polychlorinated dibenzo-r{cyrillic}-dioxins and dibenzofurans (PCDD/Fs) in this study, aiming to evaluate PCDD/F characteristic and the corresponding mass balance through the whole system. The grate-type MSWI is equipped with semi-dry scrubber, activated carbon injection, and bag filter as air pollutant control devices (APCDs). Results showed that on the output side, the stack gas, bottom ash and fly ash presented their mean dioxin levels of 0.078ng I-TEQ/Nm 3, 12.94ng I-TEQ/kg and 858ng I-TEQ/kg, respectively, and showed large similarities in congener profiles. Instead, on the input side, the municipal solid waste (MSW) presented a mean dioxin level of 15.56ng I-TEQ/kg and a remarkable difference in congener profiles compared with those of the output. The dioxin mass balance demonstrated that the annual dioxin input value was around 5.38g I-TEQ/yr, lower than the total output value (7.62g I-TEQ/yr), signifying a positive dioxin balance of about 2.25g I-TEQ/yr. © 2012 Elsevier Ltd.


Qiu X.,South China Normal University | Fang Z.,South China Normal University | Liang B.,South China Normal University | Gu F.,South China Normal University | Xu Z.,South China Institute of Environmental Sciences
Journal of Hazardous Materials | Year: 2011

The agglomeration of nanoparticles reduces the surface area and reactivity of nano zero-valent iron (NZVI). In this paper, highly dispersive and reactive NZVI immobilized in mesoporous silica microspheres covered with FeOOH was synthesized to form reactive mesoporous silica microspheres (SiO 2@FeOOH@Fe). The characteristics of SiO 2@FeOOH@Fe were analyzed by transmission electron microscopy, Fourier transform infrared spectroscopy simultaneous thermal analysis, X-ray photoelectron spectroscopy, and Brunnaer-Emmett-Teller surface area analysis. The mean particle size of the reactive mesoporous silica microspheres was 450nm, and its specific surface area was 383.477m 2g -1. The degradation of dcabromodiphenyl ether (BDE209) was followed pseudo-first-order kinetics, and the observed reaction rate constant could be improved by increasing the SiO 2@FeOOH@Fe dosage and by decreasing the initial BDE209 concentration. The stability and longevity of the immobilized Fe nanoparticles were evaluated by repeatedly renewing the BDE209 solution in the reactor. The stable degradation of BDE209 by SiO 2@FeOOH@Fe was observed within 10 cycles. Agglomeration-resistance and magnetic separation of SiO 2@FeOOH@Fe were also performed. The improved dispersion of SiO 2@FeOOH@Fe in solution after one-month storage and its good performance in magnetic separation indicated that SiO 2@FeOOH@Fe has the potential to be efficiently applied to environmental remediation. © 2011 Elsevier B.V.

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