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Zhang C.-Y.,Nankai University | Wu J.-H.,Nankai University | Zhang P.,Chengdu Academy of Environmental science | Zhang Y.-F.,Nankai University | And 3 more authors.
Research of Environmental Sciences | Year: 2014

Air samples of ambient PM10 and PM2.5 were collected in 2010, 2011, and 2012 at eight sites during winter in Chengdu, Sichuan Province. The inorganic elements, water solvent ions and carbonaceous species were measured to identify the sources of the PM10and PM2.5. The trends of PM concentration, chemical composition and sources were investigated. The concentration of PM10 was the highest in the industrial region, while PM2.5 showed regional characteristics. The sources of PM10 and PM2.5 in Chengdu were determined by chemical mass balance iteration (CMB-iteration) receptor model. The results showed that the important sources of PM10 in winter in Chengdu were suspended dust, sulfates, fly coal combustion, nitrates and vehicle exhaust, with contributions of 24%-29%, 17%-22%, 13%-16%, 6%-12% and 6%-11%, respectively, from 2010 to 2012. The important sources of PM2.5 were sulfates, suspended dust, fly coal combustion, nitrates and vehicle exhaust, with contributions of 25%-27%, 19%-22%, 12%-15%, 11%-13% and 8%-11%, respectively, from 2010 to 2012. This work indicated that secondary particles and suspended dust were the major sources of PM in Chengdu. Suspended dust and cement dust, which were mainly composed of coarse particles, contributed less year by year, while the contribution of secondary particles, which were mainly composed of fine particles, increased year by year. Fine PM pollution was serious in winter in Chengdu.

Yang H.,Beijing University of Civil Engineering and Architecture | Guo J.,Beijing University of Civil Engineering and Architecture | Lu S.,Beijing University of Civil Engineering and Architecture | Qu J.,Chengdu Academy of Environmental science | Jia J.,Beijing University of Civil Engineering and Architecture
Chinese Journal of Environmental Engineering | Year: 2016

The contents of 16 kinds of priority polycyclic aromatic hydrocarbons (PAHs) in the water hyacinth in the constructed wetlands were measured by GC/MS. The PAHs compositions were determined, and the impact of fat content on PAHs content was analyzed. The results showed that the content of PAHs in the water hyacinth was little affected by different water feeding patterns (intermittent or continuous feeding water). The contents of 16 kinds of PAHs in intermittent and continuous feeding water conditions were 1 186. 67 ng/g (dw) and 1 280.00 ng/g (dw), respectively. The most contents of PAHs are the 2 rings, 3 rings and 4 rings. In water hyacinth, the percentages of 2 rings, 3 rings, 4 rings and 5 rings PAHs in the intermittent water were 27.55%, 34.27%, 23.31% and 14.47%, whereas there were 29.43%, 33.85%, 23.81% and 13.54% in continuous water. 6 rings PAHs in water hyacinth was not detected. The enrichment rate of PAHs was 1.16%-1.99% for water hyacinth. There is some correlation between the concentration of fat content in water hyacinth and plants of PAHs, PAHs content increases with the increase of fat content. © 2016, Science Press. All right reserved.

Wang P.,Southwest University | Shang Y.-N.,Chengdu Academy of Environmental science | Shen L.-C.,Southwest University | Wu K.-Y.,Southwest University | Xiao Q.,Southwest University
Huanjing Kexue/Environmental Science | Year: 2013

Freshwater lake of the Tibetan plateau has great ecological value and extreme vulnerability. The water samples have been collected in Daggyaima Co at an altitude of 5080 m±10 m. This study has investigated the sources, the major controlling factors of the major ions, and hydrochemical evolution trend according to the hydrochemical composition of water samples. The results showed that the major cations and anion of lake water were Ca2+, Na+ and HCO3 -, respectively, and the hydrochemical type was HCO3-Ca, The total dissolved solid (TDS) was in the range of 71.2-199.8 mg·L-1. The concentrations of EC, Ca2+ and HCO3 - in water samples from Southeast areas were relatively low resulted from the rich aluminum and poor calcium of geological background and the dilution effect of surface runoff. The Na+/(Na++Ca2+) of water samples was 0.08-0.75, Cl-/(Cl-+HCO3 -) was 0.11-0.35, Ca/Na was 0.58, Mg/Ca was 0.12, and HCO3/Na was 1.46, which suggested that the hydrochemical composition of the lake water was mainly controlled by silicate rock weathering based on Gibbs model and analysis of elemental stoichiometry. The minerals participated in weathering processes included plagioclase (anorthite, albite), potassium feldspar, biotite, calcite, dolomite, gypsum, rock salt, etc. The average value of K/Na was 0.059, indicating the weathering level of potassium feldspar was relatively low. The saturation index (SI) of calcite, dolomite, gypsum, quartz and hematite contained in the lake was higher than zero, while the SI of rock salt was lower than 0, revealing the trend that the freshwater lake is turning into salt water lake in Tibetan Plateau.

Jia B.-Y.,University of Sichuan | Jia B.-Y.,Chengdu Academy of Environmental science | Tang Y.,University of Sichuan | Wu Y.-H.,University of Sichuan | Yin D.-S.,University of Sichuan
Proceedings - 2012 International Conference on Biomedical Engineering and Biotechnology, iCBEB 2012 | Year: 2012

The water quality of the Sancha Lake has declined from Class III to Class IV and Class V due to increasing eutrophication, to which human activity has contributed considerably since it was built in 1977. This research examines changes in sedimentation rate and supply of mass accumulation of the Sancha Lake in recent decades through 210Pb and 137Cs dating and records of historical events in lacustrine sediments. This research also examines the process of change in the lake environment and identifies the driving effect of human activity on the evolutionary process of the lake environment by combining the analysis on the change characteristics of the sediments' grain size and C, N and P therein. The findings of the research show that human activities, especially cage culture, application of pesticides and chemical fertilizers, and development of tourism, are the main factors causing eutrophication and environmental change in the Sancha Lake. © 2012 IEEE.

Liu G.-R.,Nankai University | Shi G.-L.,Nankai University | Zhang P.,Chengdu Academy of Environmental science | Zhou L.-D.,Chengdu Academy of Environmental science | And 2 more authors.
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2014

PM10-associated polycyclic aromatic hydrocarbons (PAHs) were investigated in summer and winter 2009 from Chengdu, China. A total of 16 priority PAHs were measured, with the total concentrations (ΣPAHs) (ng/m3) ranging from 40.25 to 150.68 in winter and from 44.51 to 71.16 in summer, respectively. The average concentration of ΣPAHs were 88.36 in winter and 64.21 in summer. Meanwhile, the spatial distribution of PAHs was discussed. The results showed that the ΣPAHs in industry region exhibited the highest concentration while those in the background region showed the lowest level. In order to explore composition of PAHs, characteristics of low ring and high ring PAHs were explored. The high ring PAHs presented high fractions (86.7%~96.1%), indicating that the PAHs might be formed in high temperature combustion processes. In addition, in order to investigate potential source categories of PAHs in PM10, three statistical methods (ratio method, hierarchical cluster analysis, principal component analysis) were employed. Agreement results were obtained from above-mentioned different methods, suggesting that the main source categories of PAHs were vehicle emission and coal and wood combustion. Finally, the risk assessment of PAHs was determined by Benzo(a)pyrene equivalent (BaPE), which suggested that the toxicity of PAHs was at high level during winter and summer time. ©, 2014, Editorial Board of China Environmental Science. All right reserved.

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