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2009 Vol.29 Issue.6,Published 2009-06-20
561 A toxicological assessment of PM10 in Lanzhou: Results from plasmid DNA assay.
XIAO Zheng-Hui, SHAO Long-Yi, ZHANG Ning
An in vitro plasmid DNA assay was employed to study the oxidative damage of airborne PM10 collected in urban and suburban sites of Lanzhou city from December 2005 to October 2006, and the causes of DNA damage induced by PM10 were investigated. The toxicity represented by oxidative damage of the PM10 varied greatly. The oxidative damage caused by PM10 collected in the winter and summer was stronger than those collected in spring and autumn. The average TD20 values (toxic dosages of PM10 causing 20% of plasmid DNA damage) of intact whole PM10 solutions from the urban site in winter, spring, summer and autumn were 17, 625, 56 and 260μg/mL, respectively, and the TD20 values of their corresponding water-soluble fraction were 62, 840, 193 and 403μg/mL, respectively. The PM10 collected during the asian dust storm episodes and after raining showed a low oxidative damage, with TD20 values of both the intact samples and water-soluble fractions being higher than 1000μg/mL. The contents of total analyzed water-soluble trace elements, revealed by ICP-MS, were negatively correlated with the TD20 values of both whole sample and corresponding water-soluble fraction of PM10, which implied that the DNA damage may be attributed to the water-soluble trace elements in PM10.
2009 Vol. 29 (6): 561-566 [Abstract] ( 235 ) [HTML 1KB] [ PDF 528KB] ( 630 )
567 Modeling and impact study of fugitive dust emissions from building construction sites.
ZHAO Pu-Sheng, FENG Yin-Chang, ZHANG Yu-Fen, ZHU Tan, JIN Jing, ZHANG Xiao-Ling
A building construction site located in Tianjin urban area was selected for study of fugitive dust emission from construction process. The ambient PM10, surface dust, meteorological condition and traffic flux were measured on site. Based on the fugitive dust model (FDM), PM10 emission factors were calculated by a Flux-FDM method developed in this study. Then by using nonlinear fitting, a quantitative mathematical model of PM10 emission factor for building construction was developed on the basis of measured data. By combination of the emission factor model and the Industrial Source Complex Model (ISC3), the impact of PM10 emissions from Tianjin construction sites on urban ambient air was simulated. The calculated average concentration of PM10 from construction sites was 20.3μg/m3 between November and December, 2003, accounting for 13.1% of ambient air PM10.
2009 Vol. 29 (6): 567-573 [Abstract] ( 305 ) [HTML 1KB] [ PDF 698KB] ( 1700 )
574 Dynamics of dry deposition velocities of atmospheric nitrogen compounds in a broadleaf forestland.
FAN Jian-Ling, HU Zheng-Yi, WANG Ti-Jian, ZHOU Jing
Surface layer turbulence characteristic parameters (U*、θ* and L) and the dry deposition velocities (Vd) of various atmospheric nitrogen compounds were calculated by Big Leaf Resistance Analogous Model based on the meteorological data collected in 2004 from the Forest Micrometeorological Experiment Sub-station, Experiment Station of Red Earth Ecology, Chinese Academy of Sciences. The annual mean Vd of particulate NO3－/NH4+, HNO3 (g), NO2 and NH3 were 0.216, 0.985, 0.115, 0.274 cm/s, respectively. The Vd of atmospheric nitrogen were higher in daytime than that in night, while the highest Vd were observed at 11:00~12:00 AM. The Vd of atmospheric nitrogen were higher in winter and spring than that in summer and autumn.
2009 Vol. 29 (6): 574-577 [Abstract] ( 250 ) [HTML 1KB] [ PDF 438KB] ( 762 )
578 Effects of enhanced temperature on algae recruitment and phytoplankton community succession.
TAN Xiao, KONG Fan-Xiang, YU Yang, SHI Xiao-Li, ZHANG Min
Effects of enhanced temperature on phytoplankton recruitment and phytoplankton community succession were analyzed by a simulation experiment. Winter sediment was collected from Taihu Lake and cultured in BG-11 medium. The incubation temperatures were enhanced from 5.5℃ to 30℃ with eight gradients, and each temperature level was kept for ten days. Microscopic morphological observation was applied to analyze algal specific growth rate (SGR) and phytoplankton community succession, meanwhile fluorescence analysis was performed to detect variations of photosynthetic pigment concentration. Recruitment of Chlorophytes and Diatoms was observed at 9℃, but that of Cyanobacteria was not evidently detected until 12.5℃. Recruitment of Cyanobacteria initiated later than Chlorophytes and Diatoms, but the specific growth rate of Cyanobacteria after recruitment was highest. Phytoplankton community was overwhelmingly composed of Cyanobacteria, Chlorophytes, and Diatoms when temperature exceeded 12.5℃. Moreover, Chlorophytes dominated phytoplankton community at 12.5℃ and 16℃, Cyanobacteria subsequently established dominance above 19.5℃. Concentration of chlorophyll a increased evidently at 9℃ and 16℃, while that of phycocyanin went up markedly only at 16℃. Pigment concentration increased with the recruitment of Chlorophytes and Diatoms synchronously, but lagged behind Cyanobacteria recruitment.
2009 Vol. 29 (6): 578-582 [Abstract] ( 267 ) [HTML 1KB] [ PDF 387KB] ( 1042 )
583 Preliminary ecological risk assessment of polycyclic aromatic hydrocarbons in main rivers of China.
FENG Cheng-Lian, LEI Bing-Li, WANG Zi-Jian
Based on the observed PAHs concentrations of different rivers in China, one hazard quotient was defined to screen the target compounds. Seven PAHs, which posed potential threat to aquatic ecosystem, including phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene and benzo[a]pyrene, were screened. Combined with the toxicity data of PAHs to aquatic organisms, the probabilistic risk approach was applied to assess the ecological risk of the seven PAHs to aquatic ecosystem. Among all the 16 investigated PAHs, ecological risk of anthracene was the highest, while the risk of chrysene was the lowest. The ecological risk of 16 individual PAHs followed the order of anthracene>pyrene>benzo[a] anthracene>fluoranthene>benzo[a]pyrene>phenanthrene>chrysene.
2009 Vol. 29 (6): 583-588 [Abstract] ( 247 ) [HTML 1KB] [ PDF 406KB] ( 1133 )
589 Non-use value evaluation of ecological resources in sanjiangyuan region.
ZENG Xian-Gang-Wang-Ke, CHENG Lei-Lei, SUN Fa-Ping
The non-use value of ecological resources in Sanjiangyuan Region was measured by contingent valuation method (CVM), and its influencing factors was analyzed. The non-use value of ecological resources in Sanjiangyuan Region was about 45.306 billion yuan/a,in which the existence value was 23.636 billion yuan/a,the bequest value was 12.591 billion yuan/a,the option value was 9.079 billion yuan/a,and the mean willingness to pay (WTP) for ecological resources in Sanjiangyuan Region was 76.3 yuan/a. Through analysis from Logit and Tobit model, it was found that the awareness, concentration, favour, age, income level and education level were extremely closely correlated with the non-use value.
2009 Vol. 29 (6): 589-593 [Abstract] ( 201 ) [HTML 1KB] [ PDF 289KB] ( 710 )
594 Environmental performance assessment of ecology construction in Zhejiang Province.
ZHANG Ming-Ming, LI Huan-Cheng, JIANG Wen, LU Xiao-Mei, WANG Li-Hong
Proximity-to-target, entropy, weighted synthesis and radar map methods were employed to provide theoretical and technical guidance for assessment of environmental performance. After defining the environmental performance connotation, a series of evaluation indexes were proposed to carry out the assessment. Detailed analysis in terms of the environmental performance index (EPI) had been finished for 11 cities in Zhejiang Province. There were significant difference among EPI values of the 11cities. The EPI values in south region were higher than those in north area. It was a positive correlation between EPI and natural resource, but a negative one between EPI and economic level. Further researches were required within a much larger region to get deep insights.
2009 Vol. 29 (6): 594-599 [Abstract] ( 223 ) [HTML 1KB] [ PDF 576KB] ( 1801 )
600 Effects of penalty design on enforcing pollution levy program: based on ecological experimental analysis.
LIU Bei-Bei, YU Yang, BI Jun, ZHANG Bing, GE Jun-Jie
To study the effects of penalty design on pollution levy program enforcement in China, the optimal decision model of a risk-neutral firm was established and the economic experiment was designed to testify the hypothesis. Effects of penalty expectation (monitoring and penalties) on individual emissions and violations were negative and significant; A firm’s marginal abatement costs of increased emissions had negative and significant effect on its choices of emissions and has no effect on its violations; Compared with penalties, monitoring frequency had larger impact on compliance rates. Policy makers should increase monitoring frequency and penalty to reduce violation and stimulate abatement. Current linear penalty functions should be changed to step-up ones. In addition, more enforcement resource should not be put on the firms with higher marginal abatement costs, but on those with larger emission volumes.
2009 Vol. 29 (6): 600-604 [Abstract] ( 185 ) [HTML 1KB] [ PDF 384KB] ( 645 )
605 Application of landscape ecological method in planning environment impact assessment—A case study for east part of Dalian Forest Park.
LI Wei, XIE De-Chang, ZHANG Jie
According to the problems of landscape ecological method application in planning environmental impact assessment (PEIA), such as assessment methods are insufficient, index system is imperfect or lack of combination with planning optimization, an evaluation index system comprised of landscape structure, landscape function and landscape intimidation was constructed with comprehensive consideration of socioeconomic factors. And accordingly the landscape ecological impact of the planning was evaluated. Meanwhile, computer model was introduced to simulate the dynamic landscape pattern of the alternatives. By analyzing the changes of landscape metrics, comparison and selection for alternatives was achieved. Based on above results, the application framework for landscape ecological method in PEIA was established and then applied in PEIA of Dalian forest park. Results showed that the plan improved the landscape patter and function, but it also increased landscape disturbance. Trend of landscape fragmentation was significant under alternative 1, and landscape developed an intensive integration trend under alternative 2.
2009 Vol. 29 (6): 605-610 [Abstract] ( 257 ) [HTML 1KB] [ PDF 978KB] ( 997 )
611 Reduction effect of sunken green space on urban rainfall-runoff pollution.
CHENG Jiang, YANG Kai, HUANG Min-Sheng, XIE Bing, LI Xiu-Yan
Based on monitoring 14 rainfall-runoff samples in 7 rainfall events, the reduction effect of sunken green space on urban rainfall-runoff pollution was discussed, and effect of influent loading, soil and land cover of sunken green space, and rainfall duration on pollution reduction rate was analyzed. Sunken green space had a better decontamination efficiency when the event mean concentration of COD, NH4+-N and TP were 56.0~216.0, 0.27~2.97 and 0.20~0.95mg/L, respectively. The average removal rate of COD, NH4+-N and TP were 52.21%, 48.98% and 47.35%, respectively. The decontamination process could be divided into two periods. In the first one hour since rainfall, the relationship between the concentrations of COD, NH4+-N and TP in influent and effluent followed linear equation. And then, the pollution reduction rate agreed with second-order kinetic model. The pollution reduction rate increased with the extension of rainfall duration. The integrated pollution reduction rate of COD, NH4+-N and TP could increase from about 40 % to 65 % when rainfall duration increased from about 3 to 20 hours.
2009 Vol. 29 (6): 611-616 [Abstract] ( 305 ) [HTML 1KB] [ PDF 532KB] ( 1628 )
617 Effects of chlorine dioxide on the inactivation of the chironomid larvae.
SUN Xing-Bin, WANG Shu-Tao, CUI Fu-Yi
Comparative experiments on the inactivation of the first instar larvae of chironomid in distilled water by chlorine and chlorine dioxide were conducted. In addition, inactivation effects of chlorine dioxide on the first instar larvae of chironomid in artificial water and raw water were evaluated. And batch experiments were performed in order to analyze the influence of pH value and temperature on the inactivation efficiency of chironomid larvae with chlorine dioxide. Chlorine dioxide possessed better inactivation effect than chlorine and complete inactivation of chironomid larvae was obtained at dose of 1.5mg/L of chlorine dioxide with 30min disposal. The pH value in range of 5.5~8.1 did not affect the inactivation efficiency of chlorine dioxide. The inactivation efficiency of chironomid larvae decreased as TOC concentration increased. With regard to the temperature, the inactivation efficiency of chironomid larvae was significantly improved with the temperature increasing within the range of 15~30℃. The inactivation rate was reduced to 84.5% when temperature reduced from 30℃ to 15℃.
2009 Vol. 29 (6): 617-621 [Abstract] ( 244 ) [HTML 1KB] [ PDF 454KB] ( 710 )
622 Impacts of wastewater treatment process on AOB and bacteria communities.
WANG Xiao-Hui, WEN Xiang-Hua, YANG Ning-Ning, XU Mei-Lan, DING , KUN
Communities of AOB in activated sludges collected from 4 wastewater treatment systems in 2 plants in Beijing were examined using specific PCR followed by terminal restriction fragment length polymorphism (T-RFLP), cloning, and sequencing of amoA genes. Communities of bacteria were also investigated by using T-RFLP based 16S rRNA genes. The T-RFLP fingerprints analysis showed that the dominant terminal restriction fragments (T-RFs) of AOB were 291, 354 bp, and the dominant T-RFs of bacteria were 115, 117, 166, 455, 465, 468, 471, 482, 800 and 893 bp etc. in all these 4 systems. The T-RFLP profiles analysis may also indicate the AOB and bacteria structures were slightly affected by the treatment process. Phylogenetic analysis of cloned amoA genes clearly showed that the dominant AOB in these 4 systems were members of Nitrosomonas europaea cluster and Nitrosomonas oligotropha cluster.
2009 Vol. 29 (6): 622-628 [Abstract] ( 204 ) [HTML 1KB] [ PDF 375KB] ( 1095 )
629 Enhancing 2,4-D degradation in an activated sludge system through plasmid mediated gene-augmentation.
TANG Hua, QUAN Xiang-Chun, WANG Ran
With plasmid pJP4 carrying genetic microorganism Pseudomonas putida SM1443::gfp2x (pJP4::dsRed) as the donor strain, which contains genetic elements encoding 2,4-dichlorophenoxyacetic acid (2,4-D) degradation on pJP4, plasmid mediated gene-augmentation was conducted in an activated sludge system operated in fed-batch runs. Effects of gene augmentation on 2,4-D degradation and system microbial community structure were investigated. Supplementation of pJP4 carrying genetic microorganism to an activated sludge system fed with 2,4-D as sole carbon source (initial concentration at 320 mg/L) could enhance 2,4-D degradation. This enhancement was only slight at the initial stage of the operation, but significantly increased with the increase in the operation time of fed-batch runs. The biggest difference in the 2,4-D average degradation rates between the gene-augmented system and its control was 6.67 mg/(L·h). One predominant transconjugant was isolated from the gene-augmented system and identified as Alcaligenes sp.::pJP4. Alcaligenes sp. itself failed to degrade 2,4-D, but demonstrated strong 2,4-D degradation ability after receiving plasmid pJP4, which was similar to a wild type 2,4-D degrading special bacteria Bacillus sp. PCR-DGGE analysis showed that gene-augmented activated sludge system maintained relatively more stable microbial community than the control system when facing 2,4-D shock loadings.
2009 Vol. 29 (6): 629-635 [Abstract] ( 240 ) [HTML 1KB] [ PDF 677KB] ( 581 )
636 Adsorption characteristics and mechanisms of p-chlorophenol by graphite.
CHEN Jian, WANG Jing, SUN Cheng
Adsorption of p-chlorophenol by graphite and mechanisms was investigated by batch adsorption experiments. And the adsorption was decreased both below pH 3 and above pH 7. H+-π interaction between p-chlorophenol molecules and protons was the primary reason for the slight decrease in p-chlorophenol adsorption by graphite below pH 3. Dramatic decrease in p-chlorophenol adsorption above pH 7 was probably caused by its increased solubility in water and elevated electrostatic repulsion experienced by adsorbate molecules on graphite surfaces. Ionic strength did not have significant impact on the adsorption. The major driving force for adsorption of p-chlorophenol on graphite was suggested to stem from the π-π interaction between the aromatic rings of graphite and p-chlorophenol molecules.
2009 Vol. 29 (6): 636-639 [Abstract] ( 200 ) [HTML 1KB] [ PDF 323KB] ( 792 )
640 Biodegradation characteristics of Acid Orange 7 under hypersaline conditions.
ZHANG Lu-Yan, WANG Jing, 吕Hong , JIN Ruo-Fei, ZHOU Ji-Ti
Aiming at intermediate autoxidation and bioactivity inhibition by hypersaline in anaerobic-aerobic biological treatment processes of azo dyes-loading wastewater, biodegradation characteristics of Acid Orange 7 (AO7) at the NaCl concentration of 100 g/L were investigated using some enhancement strategies. Addition of glucose (0.5g/L), peptone (1g/L) and yeast powder (0.5g/L) was propitious to the degradation of AO7 under hypersaline conditions. Biodecolorization rate of AO7 could be increased when acid red B was added to the anaerobic reactor. Anthraquinone-activated sludge self-immobilization system could enhance the biodecolorization of AO7 when anthraquinone was added to the salt-tolerant sludge and the maximal decolorization rate was about 92% at the anthraquinone concentration of 100mg/L. Addition of activated carbon felt as biological carrier allowed stable running of the anaerobic and aerobic reactors with a good sludge settlement and decoloration rate of 26.67mg/(L×h), and that the autoxidation of intermediate product 1-Amino-2-naphthol under aerobic condition could be inhibited effectively and over 90% of COD removal was maintained.
2009 Vol. 29 (6): 640-645 [Abstract] ( 231 ) [HTML 1KB] [ PDF 601KB] ( 897 )
646 Experimental research on the characterization and application of Mg-Fe composite flocculant.
LIU Xiong-Cai, ZHANG Yu, ZHOU Ji-Ti, CAO Tong-Chuan
A new PFMS composite flocculant was prepared by ferrous sulfate (FeSO4), magnesium oxide (MgO) and sulfuric acid (H2SO4). The structure and iron distribution of the product were investigated. The magnesium ion didn’t participate in the polymerization process, but it improved the stability of the product. In order to study the flocculation performance difference between self-made PFMS/PFS and industrial PFS, the simulated turbidity wastewater by kaolin, the simulated dye wastewater by direct fast black G and the coking wastewater were chosen to carry out the coagulation experiment of removing turbidity, color and COD, respectively. The turbidity removal efficiency by PFMS was a little higher than that of the self-made and industrial PFS, and the residual turbidity was below 5 NTU. In alkaline conditions, the decoloration rate and COD removal rate by PFMS were higher than that of the self-made and industrial PFS.
2009 Vol. 29 (6): 646-650 [Abstract] ( 209 ) [HTML 1KB] [ PDF 385KB] ( 683 )
651 Effect of soil organic matter on adsorption and desorption of oxytetracycline in soils
BAO Yan-Yu, ZHOU Qi-Xing, WAN Ying, XIE Xiu-Jie
Batch equilibrium experiments were used to investigate the adsorption and desorption of oxytetracycline (OTC) in cinnamon soil and red soil with or without soil organic matter (SOM). Results showed that all adsorption and desorption isotherms were of deviation from the linear model. All experimental adsorption and desorption data could be best described by the Freundlich model, and all coefficients (r) were up to a very significant correlation. Removal of SOM could reduce OTC adsorption capacity (lgKf) and increase OTC adsorption strength (1/n) in soil. The apparent adsorption-desorption hysteresis was found with the average hysteresis index (HIa) 0.039 and 0.015 in cinnamon soil and red soil. The removal of SOM could significantly increase HIa (P <0.01) in cinnamon soil and red soil to 0.068 and 0.028, respectively.
2009 Vol. 29 (6): 651-655 [Abstract] ( 251 ) [HTML 1KB] [ PDF 321KB] ( 1037 )
656 Soil organic carbon storage under different land-use types in Sanjiang Plain.
WANG Li-Li, SONG Chang-Chun, GE Rui-Juan, SONG Yan-Yu, LIU De-Yan
Soil organic carbon (SOC) storage in soil of 1m-depth profiles (totally 16) under 5 different land-use types in Sanjiang Plain, Northeast China was analyzed. Content and density of SOC decreased in vertical distribution under different land-use types, and the tendency of variation descended with the increase of depth. Reclamation reduced the content and density of SOC, and changed the distribution structure in topsoil. A preliminary estimate showed that the SOC storage of 1m-depth was 1.58×104t/km2 in wetland, 1.23×104t/km2 in abandoned land, 1.01×104t/km2 in woodland, 0.85×104t/km2 in paddy land and 0.99×104t/km2 in glebe. It concluded that reclamation reduced SOC storage of wetland, and the effect was more significant in farmland than in woodland. Wetland restoration could be beneficial to soil carbon sequestration and would increase the soil organic carbon storage.
2009 Vol. 29 (6): 656-660 [Abstract] ( 254 ) [HTML 1KB] [ PDF 409KB] ( 1252 )
661 Spatial variation and environment risk of cadmium in agricultural land in the Xijiang River draining of Guangxi Province.
DI Li-Mei, LIAO Xiao-Yong, YAN Xiu-Lan, CHEN Tong-Bin, LIU Hong-Bin, XIE Hua
Xijiang River draining is one of the main food grain and mine producing region in Guangxi province. In order to identify soil cadmium (Cd) spatial distribution patterns and food safety risk, soil and crop in this region were analyzed. Soil Cd concentration was in range of 0.01~33.6mg/kg and distribution of Cd decreased with distance from the upstream. The soil Cd concentration along the river channel which located 0 to 80km away from the mining area had significant differences (P<0.05) compared with that in 80~610km away from the mining area along the river channel. Based on the Cd spatial distribution in agricultural soils, hot spot areas with high Cd concentrations were in the dense mining area which located in the upper course of the draining. The results of Nemero single contamination index assessment suggested that 32.2% of the soil samples belong to the grade of high pollution. The results also showed that the rice Cd concentration was in the range of 0.01~6.37mg/kg and the daily dietary intake of Cd from rice varied from 0.47~4159μg/(人×d). Average risk index of soil Cd reached 6.49 in the dense mining area located in the upstream and this was high environmental risk area in the investigated river draining.
2009 Vol. 29 (6): 661-667 [Abstract] ( 212 ) [HTML 1KB] [ PDF 720KB] ( 858 )
668 Effects of arbuscular mycorrhizal fungi on enzymes activity in soils contaminated by phenanthrene and pyrene.
XIAO Min, GAO Yan-Zheng, LING Wan-Ting, CHENG Zhao-Xia, ZENG Yue-Chun
A greenhouse pot experiment was conducted to investigate the effects of arbuscular mycorrhiza (AM) on microbes and soil enzymes in rhizosphere and hyphosphere soil contaminated by phenanthrene and pyrene. The quantities of bacteria, fungi, and actinomyces in both rhizosphere and hyphosphere increased significantly, and the microflora changed with the inoculation of arbuscular mycorrhizal fungi (AMF). The soil contamination of phenanthrene and pyrene with lower concentration clearly stimulated the activity of enzymes including acid phosphatase, polyphenol oxidase and catalase. However, when the contamination dose was higher, their activities were inhibited. Compared with bulk soil, the activity of acid phosphatase in rhizosphere with AMF was decreased by 2.4%~23.1%, and catalase in rhizosphere was decreased by 12.6%~20.3%. By contrast, the activity of polyphenol oxidase in rhizosphere was stimulated except those treatments with high levels of PAH. Polyphenol oxidase activity in hyphosphere was 2.9%~62.9% lower, while acid phosphatase activity was 3.3%~24.0% higher than that in rhizosphere. In general, catalase activity in hyphosphere was higher than that in rhizosphere. In addition, both AM and hypha enhanced the activity of catalase in soils. The enhanced activity of polyphenol oxidase by AM in rhizosphere could be the results of improved plant growth and root activities with AMF inoculation.
2009 Vol. 29 (6): 668-672 [Abstract] ( 238 ) [HTML 1KB] [ PDF 387KB] ( 870 )
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