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Distribution and health risk assessment of organochlorine pesticides(OCPs) in industrial site soils:A case study of urban renewal in beijing,china

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Journal of environmental sciences 2009年第3期21卷 366-372页

作者： YANG Wenrui,WANG Rusong,ZHOU Chuanbin,LI FengState key laboratory of Urban and Regional ecology,research center for eco-{4. sciences,chinese academy of sciences,beijing 100085,china. [a]State key laboratory of Urban and Regional ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A field survey was conducted in a contaminated industrial site of southern beijing, china to investigate the contents and distribution of the organochlorine pesticides （α-, β-, y-, δ-HCH, p,p＇-DDT, p,p＇-DDE, p,p＇-DDD and o,p＇-DDT） in the profiles of soil, and a health risk assessment was carded out with CalTOX multimedia exposure model. Results showed that mean concentrations of total hexachlorocyclohexane isomers （HCHs） and total dichlorodiphenyltrichloroethane isomers （DDXs） in soils were in the range of 13.20- 14..71 mg/kg, and 3.02-67.4. mg/kg, respectively. Organochlorine pesticides （OCPs） content peaked in the surface and declined in soil profile with depth. The amounts of HCHs in three profiles of soil were larger than DDXs. Composition analysis indicated that there was a trend of degradation of OCPs in the site, but the mean of HCHs and DDXs concentration were over the state warning standard limit （HCHs, 0.50 mg/kg; DDXs, 0.50 mg/kg）. According to current land use development, health risk assessment with CalTOX and Monte Carlo analysis showed that health risks mainly came from two exposure pathways： dermal uptake and inhalation, and the total risk values all exceeded the general acceptable health risk value （10-6）. The sensitivity analysis indicated that five parameters significantly contributed to total risk.

关键词： pollution hexachlorocyclohexane isomers (HCHs) dichlorodiphenyltrichloroethane isomers (DDXs) soil profiles Monte Carlo sensitivity

Biologically effective ultraviolet radiation in beijing area

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Journal of environmental sciences 1993年第2期5卷 216-223页

作者： Wang Shaobin Su Weihanresearch center for eco-environmental {4., chinese academy of sciences, beijing 100085, china research center for eco-environmental {4. Chinese Academy of Sciences Beijing 100085 China. China

Ozone layer depletion implies the enhancement of solar ultraviolet radiation at the earth's surface. However, aerosol contributes to the scattering of solar radiation and leads to the reduction of UV-B radiation on the ground. In this paper, the model calculation shows that due to effects of atmospheric ozone and aerosol UV-B radiation in beijing in the past decade has decreased with the annual change rate of 0.7%, which is probably approximate to the measured values. The effects of three scenarios for long-term changes in atmospheric ozone and aerosol concentrations on UV-B radiation reaching the ground in are also discussed.

关键词： UV-B biological efftent zone aerosol beijing.

Effects of ground-level ozone (O_3) pollution on the yields of rice and winter wheat in the Yangtze River Delta

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Journal of environmental sciences 2003年第3期15卷 360-362页

作者： FENG Zong-wei, JIN Ming-hong, ZHANG Fu-zhu, HUANG Yi-zong (research center for eco-environmental {4., chinese academy of sciences, beijing\ 100085, china.) research center for eco-environmental {4. Chinese Academy of Sciences Beijing 10085 Chin

Effects of elevated O_3 on the yields of rice and winter wheat were studied by using open-top chambers(OTCs). Results showed that compared to the control treatment, 200 ppb, 100 ppb, 50 ppb treatments caused a 80.4., 58.6% and 10.5% decrease in grain yields per winter wheat plant and a 4..1%, 26.1% and 8.2% decrease in grain yield per rice plant, respectively. According to the dose-response relation educed from OTCs experiment and the monitor data of O_3 concentrations in spots, it was estimated that the yield losses of rice and winter wheat resulted by O_3 pollution in the Yangtze River Delta region in 1999 were 0.599 million ton and 0.669 million ton, economic losses were 0.539 billion RMB Yuan and 0.936 billion RMB Yuan, respectively.

关键词： rice winter wheat O_3 Yangtze River Delta

Comprehensive assessment of heavy metal pollution in river and lake sediments using face graph and index of geoaccumulation

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Journal of environmental sciences 1997年第1期9卷 40-48页

作者： Liu Wenxin Tang Hongxiao Luan Zhaokun research center for eco-environmental {4.,chinese academy of {4.,beijing 100085,china Res. Ctr. for eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

Surface sedimental samples were collected from(1)Le An River in Jiangxi Province, south of china,and(2)several lakes located in southwest of *** of heavy metals in these samples were ***,the situations of heavy metal pollution in two regions were comprehensively assessed by combined index of geoaccumulation with visualized multi- variate graphical method——modified Chernoff Face *** graphs intuitively demonstrated strong heavy metal contamination in Le An River,especially copper ***,in lakes' sedimental samples,contamination of other heavy metals showed mild or clean except cadmium and chromium.

关键词： heavy metals sediment assessment index of geoaccumulation face graph.

Coulometric determination of sulfur speciation in natural waters

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Journal of environmental sciences 1996年第4期8卷 491-498页

作者： Li Yuxian Zeng Yu Yan Huiyu(research center for eco-environmental {4.,chinese academy of {4., beijing 100085,china) Res. Ctr. for eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

A systematic analytical method for the species of trace sulfur in water has been developed by using electrochemically coulometric titration in combination with several separation and concentration *** on the reaction of iodine with sodium azide,the studies were carried out on the catalytically coulometric determination of ppb levels of ionic or molecular sulfides,thiosulfates and hydrogen sulfide in wateri constant current coulometric determination of sulfites;and indirect coulometric determination of sulfate salts and *** with the determination of the content of total sulfur,the scope of distribution of the species of inorganic sulfur(including trace sulfur compounds in labile state)and organic sulfur in water was *** method thus developed was found to be featured by being easy and reliable to operate with a higher sensitivity and reproducibility and to be applicable to the analysis of sulfur species in water.

关键词： sulfur analysis of species electrochemical technique catalytically coulometric titration indirect coulometric titration.

Trophic transfer of mercury and methylmercury in an aquatic ecosystem impacted by municipal sewage effluents in beijing, china

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Journal of environmental sciences 2010年第8期22卷 1189-1194页

作者： Jianjie Fu, Yawei Wang, Qunfang Zhou, Guibin Jiang State Key Laboratory of environmental Chemistry and ecotoxicology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china. [a] State Key Laboratory of environmental Chemistry ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Gaobeidian Lake, located in beijing, china, serves as a recipient lake for efluents from a large municipal sewage treatment plant （MSTP）. In order to evaluate the effects of discharging MSTP efluent on the mercury contamination of the local aquatic ecosystem, sediment cores, water, plankton, fish, and turtle samples were collected from Gaobeidian Lake for mercury speciation analysis. High concentrations of total mercury （T-Hg） were detected in sediment cores （5.24.17.0 μg/g dry weight （dw）, average： 10.1 μg/g）. The ratio of methylmercury （MeHg） to T-Hg was less than 0.3% in sediments and ranged from 35% to 76% in biota samples. The highest level of T-Hg and MeHg were found in aquatic bryophyte and crucian carp （3673 and 4.7 ng/g dw, respectively）. The relative contents of MeHg were significantly correlated with trophic levels （R2 = 0.5506, p 0.001）, which confirmed that MeHg can be bio-transferred and biomagnified via food chain in this aquatic ecosystem.

关键词： methylmercury total mercury trophic levels aquatic ecosystem municipal sewage treatment plants

eco－environmental　information　system　of　Tianjin　City─Design，implementation　and　applications

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Journal of environmental sciences 1994年第2期6卷 144-154页

作者： Hu Xiaolin Yang Bangjie Zong Yaoguang Lu Li(research center for eco-environmental {4..chinese academy of {4., beijing 100085, china)

This paper describes the design, implementation and applications of theeco-environmental information system in Tianjin City, which is the kernel of the decision support sys-tem for urban eco-environmental regulation (DSSUER) The design of this information system isbased on the analysis of the requirements of users. The system features that it has expendability,maintainability and universality, makes data be shared between different components of DSSUERand provides help facilities and protection. The system is built by using database and graphic basetechnologies it consists of the main control module, data-management module and data-proassingniodule. The applications of this system is demonstrated by an example which is the case ofsuitability analysis of land use for residential areas in Tianjin.

关键词： eco-environmental information system land use database and graphic base technologies.

Effects of maize root exudates and organic acids on the desorption of phenanthrene from soils

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Journal of environmental sciences 2009年第7期21卷 920-926页

作者： ZHU Yanhong, ZHANG Shuzhen, HUANG Honglin, WEN Bei State Key Laboratory of environmental Chemistry and ecotoxicology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china. [a]State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The effects of maize root exudates and low-molecular-weight-organic anions （LMWOAs） on the desorption of phenanthrene from eight artificially contaminated soils were evaluated. A significant negative correlation was observed between the amounts of phenanthrene desorbed and the soil organic carbon （SOC） contents （P 〈 0.01）, and the influences of soil pH and clay content on phenanthrene desorption were insignificant （P 〉 0.1）. Neither maize root exudates nor oxalate and citrate anions influenced desorption of phenanthrene with the addition of NaN3. A faster phenanthrene desorption occurred without the addition of NaN3 in the presence of maize root exudates than oxalate or citrate due to the enhanced degradation by root exudates. Without the addition of NAN3, oxalate or citrate at different concentrations could inhibit phenanthrene desorption to different extents and the inhibiting effect by citrate was more significant than by oxalate. This study leads to the conclusion that maize root exudates can not enhance the desorption under abiotic condition with the addition of NaN3 and can promote the desorption of phenanthrene in soils without the addition of NaN3.

关键词： phenanthrene desorption low-molecular-weight-organic anions (LMWOAs) root exudates soils

Exploiting pattern and sustainable development of marginal lands in the Three Gorge Reservoir Areas

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Journal of environmental sciences 2001年第2期13卷 173-179页

作者： WU Gang, LI Jing, KONG Hong mei, ZHAO Jing zhu, GAO Lin (Department of ecology System, research center for eco {4. sciences, chinese academy of sciences, beijing 100085, china) Department of ecology System Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

This paper studied the distribution and utilization status, reasonable exploitation patterns and potential productivity, and sustainable development of marginal lands in the Three Gorge Reservoir Areas. It has been pointed that problems of the soil fertility degradation, poor productivity in crop lands, natural disasters and environmental deterioration existed in all the exploited marginal lands. In order to maintain the sustainability of the marginal lands, following measure have been proposed: prohibiting cultivation in the crop lands with a slope more than 25°, restoring vegetation in the slope more than 25°, strengthening the basic agricultural construction, establishing the production base of woody feeds and oils, establishing a multi dimensional management model with reasonable structure and optimum function for forestry, agriculture and fishing.

关键词： marginal lands utilization pattern sustainable development Three Gorge Reservoir Are4