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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. State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 Chin

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 437 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

Effect of microbial mediated iron plaque reduction on arsenic mobility in paddy soil

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Journal of Environmental Sciences 2009年第11期21卷 1562-1568页

作者： WANG Xinjun CHEN Xueping YANG Jing WANG Zhaosu SUN Guoxin State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Research Center for Environmental Protection and Transportation Safety China Academy of Transportation Sciences Beijing 100029 China

The potential of microbial mediated iron plaque reduction, and associated arsenic （As） mobility were examined by iron reducing bacteria enriched from As contaminated paddy soil. To our knowledge, this is the first time to report the impact of microbial iron plaque reduction on As mobility. Iron reduction occurred during the inoculation of iron reducing enrichment culture in the treatments with iron plaque and ferrihydrite as the electron acceptors, respectively. The Fe（II） concentration with the treatment of anthraquinone-2, 6-disulfonic acid （AQDS） and iron reducing bacteria increased much faster than the control. Arsenic released from iron plaque with the iron reduction, and a significant correlation between Fe（II） and total As in culture was observed. However, compared with control, the increasing rate of As was inhibited by iron reducing bacteria especially in the presence of AQDS. In addition, the concentrations of As（III） and As（V） in abiotic treatments were higher than those in the biotic treatments at day 30. These results indicated that both microbial and chemical reductions of iron plaque caused As release from iron plaque to aqueous phase, however, microbial iron reduction induced the formation of more crystalline iron minerals, leading to As sequestration. In addition, the presence of AQDS in solution can accelerate the iron reduction, the As release from iron plaque and subsequently the As retention in the crystalline iron mineral. Thus, our results suggested that it is possible to remediate As contaminated soils by utilizing iron reducing bacteria and AQDS.

关键词： iron reducing bacteria iron plaque arsenic anthraquinone-2,6-disulfonic acid (AQDS) paddy soil ferrihydrite

西双版纳热带雨林与橡胶林净生态系统碳交换特征及其影响因子比较

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地球与环境 2024年

作者：刘雅琪郑惠旭张晶焦麟杰张一平陈星陈耀亮宋清海中国科学院西双版纳热带植物园中国科学院大学生命科学学院福建师范大学地理科学学院

热带地区土地利用变化深刻影响了区域碳收支状况。为加强对热带亚洲北缘碳源/汇格局认知，本研究基于涡度相关方法获取西双版纳热带雨林和橡胶林多年的气象和碳通量数据，定量评价环境因素对西双版纳不同热带森林净生态系统碳交换的影... 详细信息

热带地区土地利用变化深刻影响了区域碳收支状况。为加强对热带亚洲北缘碳源/汇格局认知，本研究基于涡度相关方法获取西双版纳热带雨林和橡胶林多年的气象和碳通量数据，定量评价环境因素对西双版纳不同热带森林净生态系统碳交换的影响。结果表明：热带雨林多年平均净生态系统碳交换（NEE）为–157.9 g C/（m2·a）(–1.6 t C/（hm2·a）)；橡胶林为–491.9 g C/（m2·a）(–4.9 t C/（hm2·a）)，均呈现碳汇效应。在季节尺度上，热带雨林和橡胶林净生态系统碳交换变化特征相反，其中，热带雨林在干季的NEE(–148.3 g C/（m2·season）)强于雨季(–9.6 g C/（m2·season）)，橡胶林雨季NEE(–376.9 g C/（m2·season）)强于干季(–115.0 g C/（m2·season）),NEE在干季受物候因素影响，在雨季主要受空气温度和饱和水汽压差调控。日尺度上，热带雨林与橡胶林的NEE均呈单峰变化曲线，日均NEE分别为–0.4 g C/（m2·d）和–1.4 g C/（m2·d），两种森林的NEE日变化主要受光合有效辐射（PAR）调控，橡胶林相比于热带雨林具有更强的光合能力；上午时段是两种森林主要的固碳时段，下午的高温抑制了森林的净碳吸收。研究结果揭示了相同环境条件对热带雨林与橡胶林净生态系统碳交换的差异性影响，为预估未来不同土地利用情景下的热带森林区域碳平衡状况提供参考。

关键词：净生态系统碳交换热带雨林橡胶林环境因子

Enhancements of Major Aerosol Components Due to Additional HONO Sources in the North China Plain and Implications for Visibility and Haze

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Advances in Atmospheric Sciences 2013年第1期30卷 57-66页

作者：安俊岭李颖陈勇李健屈玉汤宇佳 State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences

The Weather Research and Forecasting/Chemistry model （WRF-Chem） was updated by including pho- toexeited nitrogen dioxide （NO2） molecules, heterogeneous reactions on aerosol surfaces, and direct emissions of nitrous acid （HONO） in the Carbon-Bond Mechanism Z （CBM-Z）. Five simulations were conducted to assess the effects of each new component and the three additional HONO sources on concentrations of major chemical components. We calculated percentage changes of major aerosol components and concentration ratios of gas NOy （NOyg） to NOy and particulate nitrates （NO3-） to NOy due to the three additional HONO sources in the North China Plain in August of 2007. Our results indicate that when the three additional HONO sources are included, WRF-Chem can reasonably reproduce the HONO observations. Heterogeneous reactions on aerosol surfaces are a key contributor to concentrations of HONO, nitrates （NO3-）, ammonium （NH＋）, and PM2.5 （concentration of particulate matter of ≤2.5 um in the ambient air） across the North China Plain. The three additional HONO sources produced a -5% -20% increase in monthly mean daytime concentration ratios of NO3-/NOy, a -15%- 52% increase in maximum hourly mean concentration ratios of NO3-/NOy, and a -10% -50% increase in monthly mean concentrations of NOx and NH＋ across large areas of the North China Plain. For the Bohai Bay, the largest hourly increases of NO3- exceeded 90%, of NH＋ exceeded 80%, and of PM2.5 exceeded 40%, due to the three additional HONO sources. This implies that the three additional HONO sources can aggravate regional air pollution, further impair visibility, and enhance the incidence of haze in some industrialized regions with high emissions of NOx and particulate matter under favorable meteorological conditions.

关键词： HONO NOy aerosol component heterogeneous reaction WRF-Chem model

In situ enhanced bioremediation of dichlorvos by a phyllosphere Flavobacterium strain

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Frontiers of Environmental Science & Engineering 2012年第2期6卷 231-237页

作者： Jiying NING Gang GANG Zhihui BAI Qing HU Hongyan QI Anzhou MA Xuliang ZHUAN Guoqiang ZHUANG Research Centre for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China

A bacterium capable of degrading dichlorvos was isolated from the rape phyllosphere and designated YD4. The strain was identified as Flavobacterium sp., based on its phenotypic features and 16S rRNA gene sequence. Strain YD4 was able to utilize dichlorvos as the sole source of phosphorus. In situ enhanced bioremedia- tion of dichlorvos by YD4 was hereafter studied. Chlorpyrifos and phoxim could also be degraded by this strain as the sole phosphorus source. A higher degradation rate of dichlorvos was observed after spraying YD4 onto the surface of rape leaves when compared to the sterilized- YD4 and water-treated samples. The results indicated that pesticide-degrading epiphytic bacterium could become a new way for in situ phyllosphere bioremediation where the hostile niche is unsuitable for other pesticide-degrading bacteria isolated from soil and water.

关键词： enhanced bioremediation organophosphoruspesticides phyllosphere Flavobacterium sp

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. State Key Laboratory of Environmental Chemistry and Ecotoxicology

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

A novel integrated step-feed biofilm process for the treatment of decentralized domestic wastewater in rural areas of China

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Journal of Environmental Sciences 2010年第3期22卷 321-327页

作者： Hanwen Liang, Min Gao, Junxin Liu, Yuansong Wei, Xuesong Guo Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 Chin

For wastewater treatment in rural areas, a novel three-stage step-feed wastewater treatment system, combined with a drop-aeration biofilm process, was tested in the laboratory to investigate its performance in removing suspended solids （SS）, chemical oxygen demand （COD）, NH4＋-N, total nitrogen （TN）, and total phosphorus （TP）. The removal rates of SS, COD and NH4＋-N were 90%, 80%, and 90% in efluent concentrations less than 10 mg/L, 50 mg/L and 8 mg/L, respectively. The TP removal rate was less satisfactory. The C/N ratio in the raw wastewater was often less than 3.5, and the removal efficiency of TN was therefore limited. A carbon-release batch experiment was carried out to measure the feasibility of enhancing denitrification at low influent C/N ratios. The result showed that the C/N could be over 9.0 in the supernatant. Polymerase chain reaction denaturing gradient gel electrophoresis technology was used to reveal the changes in the bacterial community during different stages of the integrated step-feed biofilm process. The results showed that banding patterns and the distribution of dominant bands for the same experimental period in different aerobic zones were similar. Phylogenetic analysis indicated that lanes 10, 11 and 12, which presented three aerobic zones at the same operation period, had the closest phylogenetic relationship among the lanes.

关键词： step-feed biofilm removal efficiency PCR-DGGE C/N ratio

Size distribution and diffuse pollution impacts of PAHs in street dust in urban streams in the Yangtze River Delta

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Journal of Environmental Sciences 2009年第2期21卷 162-167页

作者： ZHAO Hongtao YIN Chengqing CHEN Meixue WANG Weidong Jefferies Chris SHAN Baoqing State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Urban Water Technology Centre University of Abertay Dundee Bell Street Dundee Scotland DD1 1HG UK

Particles of dust washed off streets by stormwater are an important pathway of polyaromatic hydrocarbons （PAHs） into urban streams. This article presented a comprehensive assessment of the size distribution of PAHs in street dust particles, the potential risks of the particles in urban streams, and the sources and sinks of PAHs in the stream network. This assessment was based on measurements of 16 PAHs from the USEPA priority list in street dust particles and river sediments in Xincheng, China. The content of total PAHs ranged from 1629 to 8986 Dg/kg in street dust particles, where smaller particles have a higher concentrations. Approximately 55% of the total PAHs were associated with particles less than 250 μm which accounted for 40% of the total mass of street dust. The PAH quantities increased from 2.41 to 46.86 μg/m2 in the sequence of new residential, rising through main roads, old town residential, commercial and industrial areas. The sediments in stream reaches in town were found to be sinks for street dust particle PAHs. The research findings suggested that particle size, land use and the hydrological conditions in the stream network were the factors which most influenced the total loads of PAH in the receiving water bodies.

关键词： PAHs street dust particle size distribution land use pollutant load

Assessment of source water contamination by estrogenic disrupting compounds in China

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Journal of Environmental Sciences 2012年第2期24卷 320-328页

作者： Weiwei Jiang YeYan Mei Ma Donghong Wang Qian Luo Zijian Wang Senthil Kumaran Satyanarayanan Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Unit of Toxicology Bharathiar University Coimbatore 641046 lndia

Detection of estrogenic disrupting compounds（EDCs） in drinking waters around China has led to rising concerns about health risks associated with these *** is,however,a paucity of studies on the occurrence and identification of the main compounds responsible for this pollution in the source *** fill this void,we screened estrogenic activities of 23 source water samples from six main river systems in China,using a recombinant two-hybrid yeast *** sample extracts induced significant estrogenic activity,with E2 equivalents（EEQ） of raw water ranging from 0.08 to 2.40 ng/***,16 samples were selected for chemical analysis by gas chromatography-mass *** EDCs of most concern,including estrone（E1）,17β-estradiol（E2）,17α-ethinylestradiol（EE2）,estriol（E3）,diethylstilbestrol（DES）,estradiol valerate（EV）,4-t-octylphenol（4-t-OP）,4-nonylphenols（4-NP） and bisphenol A（BPA）,were determined at concentrations of up to 2.98,1.07,2.67,4.37,2.52,1.96,89.52,280.19 and 710.65 ng/L,*** analysis,involving comparison of EEQ values from yeast assay and chemical analysis identified E2,EE2 and 4-NP as the main responsible compounds,accounting for the whole estrogenic activities（39.74% to 96.68%）.The proposed approach using both chemical analysis and yeast assay could be used for the identification and evaluation of EDCs in source waters of China.

关键词： source water estrogenic disrupting compounds yeast assay bioassay

Synergistic impacts of anthropogenic and biogenic emissions on summer surface O_3 in East Asia

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Journal of Environmental Sciences 2013年第3期25卷 520-530页

作者： Yu Qu Junling An Jian Li State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of Sciences

A factor separation technique and an improved regional air quality model （RAQM） were applied to calculate synergistic contributions of anthropogenic volatile organic compounds （AVOCs）,biogenic volatile organic compounds （BVOCs） and nitrogen oxides （NOx） to daily maximum surface O3（O3DM） concentrations in East Asia in summer （June to August 2000）.The summer averaged synergistic impacts of AVOCs and NOx are dominant in most areas of North China,with a maximum of 60 ppbv,while those of BVOCs and NOx are notable only in some limited areas with high BVOC emissions in South China,with a maximum of 25 *** result implies that BVOCs contribute much less to summer averaged O3DM concentrations than AVOCs in most areas of East Asia at a coarse spatial resolution （1×1） although global emissions of BVOCs are much greater than those of *** maximum total contributions of BVOCs can approach 20 ppbv in North China,but they can reach 40 ppbv in South China,approaching or exceeding those in some developed countries in Europe and North *** emissions in such special areas should be considered when O3 control measures are *** contributions among AVOCs,BVOCs and NOx significantly enhance O3 concentrations in the Beijing-Tianjin-Tangshan region and decrease them in some areas in South ***,the total contributions of BVOCs to O3DM vary significantly from day to day and from location to *** result suggests that O3 control measures obtained from episodic studies could be limited for long-term applications.

关键词： regional air quality model volatile organic compounds O3 factor separation technique synergistic contribution