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771.
772.
Huang DJ Zhang YM Song G Long J Liu JH Ji WH 《Environmental monitoring and assessment》2007,128(1-3):483-488
The Yellow River, the second largest river in China, is the most important resource of water supply in North China. In the
last 40 years, even in the upper Yellow River, with the development of industry and agriculture, more and more contaminants
have been discharged into this river and greatly polluted the water. Although a routine chemical component analysis has been
performed, little is known about the real toxic effects of the polluted water on organisms at environmental level. To explore
whether the pollutants induced oxidative stress and damage to aquatic organisms, malondialdehyde (MDA) level and activities
of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST) in hepatopancreas,
kidney and intestine of the field-collected carp Cyprinus carpio from a mixed polluted (Lanzhou Region, LZR) and a relatively unpolluted (Liujiaxia Region, LJXR) sites of the upper Yellow
River were measured. The results showed that when the values of LZR compared with those of LJXR, SOD and GST activities increased
and GPx activity decreased significantly in all the three organs (P < 0.05–0.01); CAT activity decreased but MDA level increased significantly (P < 0.05–0.01) only in kidney and intestine. In conclusion, the results of this study suggest that the pollutants can induce
obvious oxidative damage in the carp, and the SOD, GST and GPx might be better indicators for the oxidative damage in aquatic
organisms. 相似文献
773.
The Natural Vegetation Responses to the Groundwater Change Resulting from Ecological Water Conveyances to the Lower Tarim River 总被引:4,自引:0,他引:4
This paper takes the ecological water conveyance project (EWCP) that transfers water from the Bosten Lake, to Daxihaizi Reservoir, and finally to the Taitema Lake as a case study to analyze
the dynamic change of the groundwater depth, the vegetation responses to the elevation of the groundwater depth as well as
the relationship between the groundwater depth and the natural vegetation. The results from many years’ monitoring in field
indicate: (1) the groundwater depth has been elevating gradually with the increase in the times of watering and the elevation
range has been expanding continuously in the lower reaches of Tarim River. Correspondingly, the natural vegetation has a favorable
response to the elevation of the groundwater depth. The change of the natural vegetation has accordance with that of the groundwater
depth. Such facts not only show that groundwater is a key factor to the growth of the native vegetation but also prove it
is feasible that the degraded ecosystem can be restored and protected by the EWCP; (2) the results of analysis of the spatial-temporal response of the natural vegetation to watering reveals that the beneficial
influence of the EWCP on the ecosystem in the lower Tarim River is a long-term process; (3) in terms of the function and structure of ecosystem
after watering in the lower reaches of Tarim River, the EWCP does not still reach the goal of ecological restoration at a large spatial scale at present. Based on such monitoring results,
some countermeasures and suggestions for the future restoration strategy are proposed so as to provide a theoretical basis
for restoring and protecting the ecosystem in Tarim River, and meanwhile it can also provide some scientific references for
implementing the similar ecological projects in other areas. 相似文献
774.
Song YF Gong P Wilke BM Zhang W Song XY Sun TH Ackland ML 《Journal of environmental monitoring : JEM》2007,9(2):182-186
Genotoxicity potential of soils taken from wastewater irrigation areas and bioremediation sites was assessed using the Vicia faba root tip micronucleus assay. Twenty five soils were tested, of which 8 were uncontaminated soils and taken as the control to examine the influence of soil properties; 6 soils were obtained from paddy rice fields with a history of long-term wastewater irrigation; 6 soils were obtained from bioremediation sites to examine effects of bioremediation; and 5 PAH-contaminated soils were used to examine methodological effects between direct soil exposure and exposure to aqueous soil extracts on micronuclei (MN) frequency ( per thousand) in the V. faba root tips. Results indicate that soil properties had no significant influences on MN frequencies (p > 0.05) when soil pH varied between 3.4 to 7.6 and organic carbon between 0.4% and 18.6%. The MN frequency measured in these control soils ranged from 1.6 per thousand to 5.8 per thousand. MN frequencies in soils from wastewater irrigation areas showed 2- to 48-fold increase as compared with the control. Soils from bioremediation sites showed a mixed picture: MN frequencies in some soils decreased after bioremediation, possibly due to detoxification; whereas in other cases remediated soils induced higher MN frequencies, suggesting that genotoxic substances might be produced during bioremediation. Exposure to aqueous soil extracts gave a higher MN frequency than direct exposure in 3 soils. However, the opposite was observed in the other two soils, suggesting that both exposure routes should be tested in case of negative results from one route. Data obtained from this study indicate that the MN assay is a sensitive assay suitable for evaluating genotoxicity of soils. 相似文献
775.
776.
Shuling Song Xiaodong Ma Ling Tong Qin Tian Yi Huang Shaoquan Yin Hongbin Sun 《Environmental monitoring and assessment》2013,185(9):7225-7229
Forty-eight human breast milk samples were collected from mothers in Beijing. The hexachlorocyclohexane (HCH) and dichlorodiphenyltrichloroethane (DDT) (including α-HCH, β-HCH, γ-HCH, δ-HCH, p,p′-DDE, p,p′-DDD, o,p′-DDT, and p,p′-DDT) contents of the samples were determined by gas chromatography/electron capture detection and gas chromatography/mass spectrometry. α-HCH, β-HCH, γ-HCH, p,p′-DDE, p,p′-DDD, and p,p′-DDT were detected at rates of 20, 100, 10, 100, 10, and 22 %, respectively. The average residue levels in the samples were 174.6 ng/g fat for β-HCH, 333.8 ng/g fat for p,p′-DDE, 6.57 ng/g fat for α-HCH, 7.67 ng/g fat for γ-HCH, 4.18 ng/g fat for p,p′-DDD, and 11.4 ng/g fat for p,p′-DDT. The results showed that the infants’ daily intake levels of HCH and DDT were 0.95 and 1.76 μg/kg body weight/day, respectively. Our result suggested that the total residue level of these organochlorine pesticides in breast milk from Beijing decreased and was lower than that from other coastal and heavy industrial cities in China. On the other hand, the levels of HCH and DDT were higher than those from some developed countries, but lower than those from other developing countries such as India. 相似文献
777.
Ji MK Park WB Khan MA Abou-Shanab RA Kim Y Cho Y Choi J Song H Jeon BH 《Journal of environmental monitoring : JEM》2012,14(4):1153-1158
Nitrate (NO(3)(-)) is a commonly found contaminant in groundwater and surface water. It has created a major water quality problem worldwide. The laboratory batch experiments were conducted to investigate the feasibility of HCl-treated zero-valent iron (Fe(0)) combined with different adsorbents as hybrid systems for simultaneous removal of nitrate (NO(3)(-)) and ammonium (NH(4)(+)) ions from aqueous solution. The maximum NO(3)(-) removal in combined Fe(0)-granular activated carbon (GAC), Fe(0)-filtralite and Fe(0)-sepiolite systems was 86, 96 and 99%, respectively, at 45 °C for 24 h reaction time. The NO(3)(-) removal rate increased with the increase in initial NO(3)(-) concentration. The NO(3)(-) removal efficiency by hybrid systems was in the order of sepiolite > filtralite > GAC. The NH(4)(+) produced during the denitrification process by Fe(0) was successfully removed by the adsorbents, with the removal efficiency in the order of GAC > sepiolite > filtralite. Results of the present study suggest that the use of a hybrid system could be a promising technology for achieving simultaneous removal of NO(3)(-) and NH(4)(+) ions from aqueous solution. 相似文献
778.
Xiu Feng Cao Miao Liu Yu Fang Song M. Leigh Ackland 《Environmental monitoring and assessment》2013,185(3):2231-2241
Surface soil (0–20 cm) samples (n?=?143) were collected from vegetable, maize, and paddy farmland used for commercial crops in Liaoning, China. Sixteen priority polycyclic aromatic hydrocarbons (PAHs) listed in US Environmental Protection Agency were analyzed by high-performance liquid chromatography using a fluorescence detector. The soil concentrations of the 16 PAH ranged from 50 to 3,309 ng/g with a mean of 388 ng/g. The highest concentration of total PAHs found in soil of the vegetable farmland was 448 ng/g in average, followed by maize and paddy with total PAHs of 391 and 331 ng/g, respectively. Generally, the low molecular weight PAHs were more predominant than the high molecular weight PAHs in most of the soils. The evaluation of soil PAH contamination based on the Canadian criterion indicated that only naphthalene, phenanthrene, and pyrene were over the target values in several sampling sites. Isomer pair ratios and principal component analysis indicated that biomass and coal combustion were the main sources of PAHs in this area. And the average value of total B[a]Peq concentration in vegetable soils was higher than paddy and maize soils. We suggest that biomass burning should be abolished and commercial farming should be carried out far from the highways to ensure the safety of food products derived from commercial farming. 相似文献
779.
In this study, we present the application of the passive microwave emission models to snow-cover environment monitoring and
assessment in Northeast China. The study employs the radiative transfer function and strong fluctuation theory to develop
the models. We used the exponential form of a spherical symmetric correlation function to describe random permittivity fluctuations.
From strong fluctuation, we then obtained the phase matrix and extinction coefficients of snow-packs for the spherical symmetric
correlation function. We also used the vector radiative transfer formula for the layer of a random medium by solving Gaussian
quadrature and eigen analysis. By comparing the brightness temperatures at 5, 10.7, 18, and 37 GHz, the modelling results
agreed with experimental data of dry-snow physical parameters as measured in the fieldwork. 相似文献
780.
Risk assessment and monitoring of dinotefuran and its metabolites for Chinese consumption of apples 总被引:1,自引:0,他引:1
Weiwei Yu Min Huang Jiaojiao Chen Sizhuo Wu Kunming Zheng Song Zeng Kankan Zhang Deyu Hu 《Environmental monitoring and assessment》2017,189(10):521
Residues of dinotefuran and its metabolites, 1-methyl-3-(tetrahydro-3-furylmethyl)urea (UF) and 1-methyl-3-(tetrahydro-3-furylmethyl)guanidine (DN), in apple were investigated using a “QuEChERS” (quick, easy, cheap, effective, rugged, safe) pretreatment and liquid chromatography–tandem mass spectrometry. Limits of detection (LODs) and quantification (LOQs) of dinotefuran, UF, and DN in apples were 0.011–0.960 and 0.037–3.200 μg/kg, respectively. The average recoveries of dinotefuran, UF, and DN in apple ranged from 70.0 to 83.6% with relative standard deviations less than 13%. A formulation of 20% water-dispersible dinotefuran granules was sprayed at 1–1.5-fold the recommended dose 3–4 times on apple trees. Total terminal residues of dinotefuran in apple were less than 2 mg/kg, which is the maximum residue limit (MRL) set by Japan. When following the recommended application guidelines, dinotefuran is unlikely to present significant health concerns to the Chinese population because the risk quotient (RQ) is less than 100%. This work could provide guidance for the safe use of dinotefuran and serve as a reference for the establishment of a maximum residue limit of dinotefuran in apple in China. 相似文献