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131.
Kuang YW Zhou GY Da Wen Z Liu SZ 《Environmental science and pollution research international》2007,14(4):270-275
Goal, Scope and Background Rapid urbanization and the expansion of industrial activities in the past several decades have led to large increases in emissions
of pollutants in the Pearl River Delta of south China. Recent reports have suggested that industrial emission is a major factor
contributing to the damages in current natural ecosystem in the Delta area. Tree barks have been used successfully to monitor
the levels of atmospheric metal deposition in many areas, but rarely in China. This study aimed at determining whether atmospheric
heavy metal deposition from a Pb-Zn smeltery at Qujiang, Guangdong province, could be accurately reflected both in the inner
bark and the outer bark of Masson pine (Pinus massoniana L.). The impact of the emission from smeltery on the soils beneath the trees and the relationships of the concentrations
between the soils and the barks were also analyzed.
Methods Barks around the bole of Pinus massoniana from a pine forest near a Pb-Zn smeltery at Qujiang and a reference forest at Dinghushan natural reserve were sampled with
a stainless knife at an average height of 1.5 m above the ground. Mosses and lichens on the surface barks were cleaned prior
to sampling. The samples were carefully divided into the inner bark (living part) and the outer bark (dead part) in the laboratory,
and dried and ground, respectively. After being dry-ashed, the powder of the barks was dissolved in HNO3. The solutions were analyzed for iron (Fe), manganese (Mn), copper (Cu), zinc (Zn), chromium (Cr), nickel (Ni) and cobalt
(Co) by inductively coupled plasmas emission spectrometry (ICP, PS-1000AT, USA) and Cadmium (Cd) and lead (Pb) by graphite
furnace atomic absorption spectrometry (GFAAS, ZEENIT 60, Germany). Surface soils (0–10 cm) beneath the sample trees were
also collected and analyzed for the selected metals.
Results and Discussion Concentrations of the selected metals in soils at Qujiang were far above their environmental background values in the area,
except for Fe and Mn, whilst at Dinghushan, they were far below their background values, except for Cd and Co. Levels of the
metals, in particular Pb and Zn, in the soils beneath the sample trees at Qujiang were higher than those at Dinghushan with
statistical significance. The result suggested that the pine forest soils at Qujiang had a great input of heavy metals from
wet and dry atmospheric deposition, with the Pb-Zn smeltery most probably being the source.
Levels of Cu, Fe, Mn, Zn, Ni and Pb at Qujiang, both in the inner and the outer bark, were statistically higher than those
at Dinghushan. Higher concentrations of Pb, Fe, Zn and Cu may come from the stem-flow of elements leached from the canopy,
soil splash on the 1.5 m height and sorption of metals in the mosses and lichens growing on the bark, which were direct or
indirect results from the atmospheric deposition. Levels of heavy metals in the outer barks were associated well with the
metal concentrations in the soil, reflecting the close relationships between the metal atmospheric deposition and their accumulation
in the outer bark of Masson pine. The significant (p<0.01) correlations of Fe-Cu, Fe-Cr, Fe-Pb, Fe-Ni, Pb-Ni, and Pb-Zn in
the outer barks at Qujiang again suggested a common source for the metals. The correlation only occurred between Pb and Ni,
Cd and Co in the outer barks at Dinghushan, which suggested that those metals must possibly have other uncommon sources.
Conclusions Atmospheric deposition of the selected metals was great at Qujiang, based on the levels in the bark of Pinus massoniana and on the concentrations in the soils beneath the trees compared with that at Dinghushan. Bark of Pinus massoniana, especially the outer bark, was an indicator of metal loading at least at the time of sampling.
Recommendations and Perspectives The results from this study and the techniques employed constituted a new contribution to the development of biogeochemical
methods for environmental monitoring particularly in areas with high frequency of pollution in China. The method would be
of value for follow up studies aimed at the assessment of industrial pollution in other areas similar with the Pearl River
Delta. 相似文献
132.
Feng Y Shi G Wu J Wang Y Zhu T Dai S Pei Y 《Journal of the Air & Waste Management Association (1995)》2007,57(2):164-171
Particle-associated polycyclic aromatic hydrocarbon (PAH) concentrations were investigated at six sampling sites in the heating (February to March 2001) and nonheating (August to September 2001) periods in an industrial city in Northern China. Thirteen PAHs were measured. The total average concentrations (nanograms per meter cubed) of PAHs ranged between 78.93 and 214.63 during the heating period and from 31.48 to 102.26 in the nonheating period. Benzo(a)pyrene occurred at the highest level at a site near an industrial area but occurred at low concentrations far from the city center and industrial areas. In addition, ambient PAH profiles were studied. The five and six-ring species occurred in high fractions at the sampling site. By diagnostic ratio analysis, the major source at each sampling site in the city was coal combustion in the heating period; in the nonheating period, the major sources were relatively complex. Finally, the similarities among the six regions were assessed by principal component analysis, cluster analysis, and coefficient of divergence. These multivariate statistical analyses produced similar results, which agreed with the results from the diagnostic ratio analysis. 相似文献
133.
134.
135.
Ting Zhang Wen-Long Yang She-Jun Chen Dian-Long Shi Hu Zhao Yi Ding Ye-Ru Huang Nan Li Yue Ren Bi-Xian Mai 《Environmental monitoring and assessment》2014,186(8):5285-5295
Polybrominated diphenyl ethers (PBDEs), organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polycyclic aromatic hydrocarbons (PAHs) in 25 surface sediments in three cities (Nantong, Wuxi, and Suzhou) in the Yangtze River Delta, eastern China were measured. The mean concentrations were 378, 45.8, 1.98, 4,002 ng/g for PBDEs, OCPs, PCBs, and PAHs, respectively. Their levels in the sediments in the three cities were generally consistent with the city industrialization. PBDEs and OCPs were markedly dominated by deca-BDE (>90 %) and DDTs (>70 %). A principle component analysis of the analytes identified three major factors suggesting different sources of the contaminants in the sediments. PBDEs and the organic carbon in the sediments have common sources from industrial activities; whereas OCPs and PCBs, correlated with the second factor, were mainly from historical sources. The third factor with loadings of PAHs is indicative of various combustion sources. Ecological risk assessment indicated that the potential highest risk is from DDTs, for which 22 sites exceed the effects range low (ERL) values and three sites exceed the effects range median (ERM) value. 相似文献
136.
137.
D. Luján-Rhenals Z. Shi S. C. Ricke 《Journal of environmental science and health. Part. B》2018,53(1):12-17
Soybean meal (SBM) is a product generated from the manufacture of soybean oil and has the potential for use as a source of fermentable sugars for ethanol production or as a protein source for animal feeds. Knowing the levels of nitrogen available from ammonium is a necessary element of the ethanolic fermentation process while identifying the levels of essential amino acids such as lysine is important in determining usage as a feed source. As such the purpose of this study was to quantify total nitrogen and ammonium in the liquid fraction of hydrolyzed SBM and to evaluate total and bioavailable lysine in the solid fraction of the hydrolyzed SBM. The effects of acid concentration, cellulase and β-glucosidase on total and ammonium nitrogen were studied with analysis indicating that higher acid concentrations increased nitrogen compounds with ammonium concentrations ranging from 0.20 to 1.24 g L?1 while enzymatic treatments did not significantly increase nitrogen levels. Total and bioavailable lysine was quantified by use of an auxotrophic gfpmut3 E.coli whole-cell bioassay organism incapable of lysine biosynthesis. Acid and enzymatic treatments were applied with lysine bioavailability increasing from a base of 82% for untreated SBM to up to 97%. Our results demonstrated that SBM has the potential to serve in ethanolic fermentation and as an optimal source essential amino acid lysine. 相似文献
138.
Jiaxin Li Pengsi Wang Shangmei Shi Jian Xue 《Environmental monitoring and assessment》2018,190(5):315
Due to the widespread use of pesticides, human exposure to pesticides is possible and can potentially cause adverse impacts on public health. We measured 137 pesticides including organophosphorus, organochlorine, pyrethroid and carbamate pesticides together with various herbicides in 100 human blood samples collected from the general population in Beijing. The samples were analysed by triple quadrupole tandem gas chromatography-mass spectrometry. In total, 24 organochlorine pesticides, 5 pyrethroid pesticides and 6 organophosphorus pesticides were detected. The detection rates of HCB, α-HCH, β-HCH, γ-HCH, p,p′-DDE and quintozene were 99, 96, 74, 72, 96 and 95%, respectively. No statistically significant gender difference in the blood concentrations of the pesticides was found. Consistent with the trend of the increasing β-HCH, p,p′-DDE and quintozene concentrations with age, a strong positive correlation between the age and concentrations of β-BHC, p,p′-DDE and quintozene was observed. 相似文献
139.
Han Jiangpei Shi Liangsheng Wang Yakun Chen Zhuowei Wu Laosheng 《Environmental science and pollution research international》2018,25(15):14511-14520
Environmental Science and Pollution Research - Anaerobic batch experiments were conducted to study the regulatory role of endogenous iron in greenhouse gas emissions under intensive nitrogen... 相似文献
140.
三峡库区消落带农用坡地磷素径流流失特征 总被引:1,自引:0,他引:1
消落带是三峡库区重要的生态交错带,但自发农用和无序开发可能会造成更多的氮磷流失,进而加剧三峡库区水体富营养化。通过对库区连续3 a的定位监测(2011~2013年),研究了三峡库区消落带农用坡地的磷素流失特征。结果表明:次降雨事件中常规施肥处理的地表径流、壤中流总磷平均浓度分别为0.848±0.153、0.140±0.006 mg/L,其中地表径流中磷的形态以颗粒态为主,壤中流以溶解态的生物可利用磷为主。常规施肥下,地表径流、壤中流磷素年均流失通量分别为0.236±0.004、0.100±0.003 kg·hm 2,地表径流、壤中流磷素流失通量分别占总流失通量的70.2%、29.8%,地表径流是坡地磷素流失的主要途径,但壤中流也是不可忽视的重要途径。与常规施肥处理相比,减量施肥处理地表径流、壤中流磷素流失量分别降低了45.3%、40.0%。建议采取减量施肥的方式,以降低营养盐负荷,保护水环境。 相似文献