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Journal of Environmental Sciences 2012年第10期24卷 1723-1730页

作者： Jingguo Cui Baoqing Shan wenzhong tang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-environmental SciencesChinese Academy of ScieneesBeijing 100085China

The ratio of metal：P stoichiometry was used to identify the accumulation pathways of heavy metals （V, Cr, Co, Ni, Cu, Cd, and Pb） from periphyton to snails Cipangopaludina chinensis Gray （C. chinensis） in the Bai River watershed. The results showed that periphyton communities were mainly composed of two types of algae, filamentous green algae and unicellular diatoms. The proportion of unicellular diatoms in the periphyton community is a key factor that influences metal accumulation in C. chinensis. The V, Cr, Co, Ni, and Cd content of C. chinensis increased steadily as the corresponding metal content of periphyton increased, but Cu and Pb in the snail did not increase in the periphyton. Mechanisms of V, Cr, and Ni accumulation were found to be related to the proportion of diatoms, while Cd and Pb accumulation were dependent on the physiological characteristics of C. chinensis. The accumulation of Cu in C. chinensis was closely related to their grazing behavior. The metal：P stoichiometry revealed that Cr, Ni, and Cd can reduce the potential ecological risks associated with increased P inputs to the ecosystem. V and Co were considered to be relatively safe, regardless of the periphyton P content. Finally, Pb may not be prone to transfer to higher trophic levels, and may pose the lowest ecological risks of the studied heavy metals, but Cu can cause potential ecological risks when eutrophication has occurred.

关键词： heavy metal metal:P periphyton Chinese mystery snails Cipangopaludina chinensis

Evaluating heavy metal contamination of riverine sediment cores in different land-use areas

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Frontiers of Environmental Science & Engineering 2020年第6期14卷 147-157页

作者： wenzhong tang Liu Sun Limin Shu Chuang Wang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Anthropogenic activities are regarded as the main sources of heavy metal pollution,yet few studies have investigated the effects of land-use setting on heavy metal accumulation in riverine *** on both total contents and geochemical fractions,heavy metal pollution,risk and toxicity were determined in riverine sediment cores from different land-use areas(mountain area-MA,farm area-FA,city area-CA,and industrial area-LA)of the Yang River Basin in North *** results showed that FA had higher contents of riverine sedimentary Cu;CA had higher contents of Cd;*** higher contents of both Cd and *** riverine sediments from FA and IA were contaminated with the investigated metals,although these concentrations were evaluated to have low potential ecological risk and no toxicity to benthic ***,a high proportion of Cd in the B1 fraction of riverine sediments in IA indicating high risk should receive more *** B1 fraction largely determined the contamination,risk and toxicity levels associated with heavy metals in the riverine sediments of the Yang River Basin.

关键词： Heavy metals Riverine sediments Pollution Land-use

A passive sampler for synchronously measuring inorganic and organic pollutants in sediment porewater:Configuration and field application

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Journal of Environmental Sciences 2024年第2期136卷 201-212页

作者： Pei Lei Mingying Chen Nan Rong wenzhong tang Hong Zhang School of Environment Nanjing Normal UniversityNanjing 210023China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China South China Institute of Environmental Sciences Ministry of Ecology and EnvironmentGuangzhou 510530China State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control Guangzhou 510530China University of Chinese Academy of Sciences Beijing 100049China

In situ measurement of multiple pollutants coexisting in sediment porewater is an essential step in comprehensively assessing the bioavailability and risk of pollutants,but to date,this needs to be better *** this study,a passive sampler,consisting of an“I-shaped”supporting frame and inorganic/organic sampling units,incorporating equilibrium dialysis theory and kinetic/equilibrium sorption principle,was developed for the synchronous measurement of inorganic(e.g.,phosphorus and metal(loid)s)and organic pollutants(e.g.,parent and substituted PAHs).The equilibrium time and sampling rates were explored in laboratory tests to support in situ *** of pollutants in porewater within a vertical resolution of centimeters,i.e.,1 cm and 2 cm for inorganic and organic pollutants,respectively,were obtained by field deployment of the sampler for further estimation of diffusive fluxes across the sediment-water *** results suggested that the role of sediments for a specific pollutant may change(e.g.,from“sink”to“source”)during the sampling *** study demonstrated the feasibility of synchronous measurement of inorganic and organic pollutants in sediment porewater by the passive *** addition,it provided new insight for further investigation into the combined pollution effects of various pollutants in sediments.

关键词： Passive sampling Bioavailability Polycyclic aromatic hydrocarbons Combined pollution Diffusive flux

Comprehensive analysis of nitrogen distributions and ammonia nitrogen release fluxes in the sediments of Baiyangdian Lake, China

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Journal of Environmental Sciences 2019年第2期31卷 319-328页

作者： Yaoyao Zhu Xin Jin wenzhong tang Xin Meng Baoqing Shan State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of Sciences University of Chinese Academy of Sciences

The condition of Baiyangdian Lake(BYDL) will improve as the Xiongan New Area evolves and fulfills its role of easing overcrowding and supporting economic growth. Water and sediment samples from BYDL were analyzed to provide information on nitrogen(N) contamination in BYDL. The mean ammonium N(NH_4^+-N), nitrate N, and total N concentrations in the water samples were 0.36, 0.12, and 2.22 mg/L, respectively, and the ranges were 0.003–8.38, 0.06–0.30,and 1.25–10.34 mg/L, respectively. The N concentrations in water gradually increased from the north to the south of BYDL. Sediment at 90% of the sampling sites was in or above the moderately contaminated class(1000–2000 mg/kg) defined in US Environmental Protection Agency total N pollution standards. Positive NH_4^+-N fluxes were found for 28 of the 34 sediment core samples, so the potential for NH_4^+-N being released from sediment was relatively high. The NH_4^+-N fluxes were 5.35–48.76 mg/m^2/day, and the mean and maximum fluxes were 8.71 and 48.76 mg/m^2/day, respectively. Benthic organisms will be affected more by NH_4^+-N and NH_3·H_2O in the surface sediment pore water(mean concentrations 4.93 and 0.13 mg/L, respectively) than by the other forms of N.

关键词： Nitrogen Ammonia nitrogen Baiyangdian Lake Flux Sediment

Dynamic Meta-Modeling Method to Assess Stochastic Flutter Behavior in Turbomachinery

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Computer Modeling in Engineering & Sciences 2022年第10期133卷 171-193页

作者： Bowei Wang wenzhong tang Lukai Song Guangchen Bai School of Computer Science and Engineering Beihang UniversityBeijing100191China Research Institute of Aero-Engine Beihang UniversityBeijing100191China School of Energy and Power Engineering Beihang UniversityBeijing100191China

With increasing design demands of turbomachinery,stochastic flutter behavior has become more prominent and even appears a hazard to reliability and *** flutter assessment is an effective measure to quantify the failure risk and improve aeroelastic ***,for complex turbomachinery with multiple dynamic influencing factors(i.e.,aeroengine compressor with time-variant loads),the stochastic flutter assessment is hard to be achieved effectively,since large deviations and inefficient computing will be incurred no matter considering influencing factors at a certain instant or the whole time *** improve the assessing efficiency and accuracy of stochastic flutter behavior,a dynamic meta-modeling approach(termed BA-DWTR)is presented with the integration of bat algorithm(BA)and dynamic wavelet tube regression(DWTR).The stochastic flutter assessment of a typical compressor blade is considered as one case to evaluate the proposed approach with respect to condition variabilities and load *** evaluation results reveal that the compressor blade has 0.95% probability to induce flutter failure when operating 100% rotative rate at t=170 *** total temperature at rotor inlet and dynamic operating loads(vibrating frequency and rotative rate)are the primary sensitive parameters on flutter failure *** comparisons,the presented approach is validated to possess high-accuracy and highefficiency in assessing the stochastic flutter behavior for turbomachinery.

关键词： Stochastic flutter assessment turbomachinery meta-model tube regression

Key strategies for the restoration of Dongting Lake in Middle Yangtze,China

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Journal of Environmental Sciences 2021年第2期33卷 360-362页

作者： Hong Zhang wenzhong tang Xiaokang Xin Wei Yin State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Enuironmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Changjiang Water Resources Protection Institute Wuhan 430051China

The Yangtze River Economic Belt(YREB)has been established since 2015 by the Chinese Government as a strategy in regional economic *** 40%of China’s polulatin resides in the YREB aera,and YREB contributes more than 40... 详细信息

关键词： Yangtze Middle development.

Determining cadmium bioavailability in sediment profiles using diffusive gradients in thin films

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Journal of Environmental Sciences 2020年第5期32卷 160-167页

作者： Zhixin Song Gangfu Song wenzhong tang Dandan Yan Minghai Han Baoqing Shan School of Environmental and Municipal Engineering North China University of Water Resources and Electric PowerZhengzhou450011China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing100085China University of Chinese Academy of Sciences Beijing100049China Henan Luhun Reservoir Administration LuoYang471023China

Cadmium(Cd)uptake by plants or benthic organisms largely depends on its bioavailability in sediments,so it is necessary to understand Cd bio availability for determining its ecological risks in riverine *** water is easily disturbed during sample collection,indicating that there was a shortage of traditional methods for investigating Cd bio ***,sediment cores were collected from rivers,after which sequential extraction and diffusive gradients in thin films(DGT)method were employed to determine Cd potential bio availability in the sediments and pore *** found that Cd concentrations measured by DGT were lower than that in pore water profiles,and Cd distribution in various fractions changed *** correlation analysis showed significant positive correlations between Cd concentrations measured by DGT and total Cd concentrations(r^2=0.76),exchangeable and weak acid soluble fraction(r^2=0.68),ferromanganese fraction(r^2=0.72)and bound organic matter or oxidizable fraction(r^2=0.54).However,the correlation was relatively low between Cd concentrations measured by DGT and that in pore water profiles(r^2=0.26).These results demonstrated that DGT method could provide more accurate information of Cd bio availability in sediment profiles than traditional methods.

关键词： Cadmium Sequential extraction Diffusive gradients thin films Bioavailability

Spatial and temporal distribution of Mo in the overlying water of a reservoir downstream from mining area

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Journal of Environmental Sciences 2021年第4期33卷 256-262页

作者： Zhixin Song Gangfu Song wenzhong tang Yu Zhao Dandan Yan Weilong Zhang School of Environmental and Municipal Engineering North China University of Water Resources and Electric PowerZhengzhou 450011China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing100049China

This study aimed to evaluate the spatial and temporal variations of molybdenum(Mo)in the downstream water body of a Mo mine during three hydrologic periods(wet,dry and medium seasons).The physical properties in Luhun Reservoir reflected seasonal variations in different hydrological *** redox potential(ORP)and dissolved oxygen(DO)increased in the dry *** concomitant decrease in temperature(T),conductivity(COND)and total dissolved solids(TDS)were lowest in the wet *** p H value did not change significantly during the three hydrologic *** distribution of Mo in the dry season was high in upstream and low in downstream areas,which was significantly different from that of the wet and medium *** total Mo concentration in wet(150.1μg/L)and medium season(148.2μg/L)was higher than that in the dry season,but the TDS(288.3 mg/L)and the percentage dissolved Mo(81.3%)in overlying water was lowest in the wet *** was no significant relationship between the dissolved Mo and the total Mo with *** the dry season,the mean total Mo concentration was 116.3μg/L,which was higher than the standard limit value(70μg/L)for drinking water(US EPA-United States Environmental Protection Agency recommended value 40μg/L).Non-point source pollution is the main characteristic of mining area pollution,which was closely related to ***,the Luhun Reservoir contains substantial Mo pollution,which was a significant concern given that it is used as a source of drinking and irrigation water.

关键词： Seasonal variations Spatial Temporal Molybdenum Mining areas

Source apportionment and specific-source-site risk of quinolone antibiotics for effluent-receiving urban rivers and groundwater in a city, China

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Journal of Environmental Sciences 2024年第10期144卷 185-198页

作者： Yu Zhao Yuanmeng Song Lulu Zhang Bo Zhao Mengqi Lu Jiansheng Cui wenzhong tang State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of ScienceBeijing 100085China College of Environment Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050000China University of Chinese Academy of Sciences Beijing 100049China

There is a large surface-groundwater exchange downstream ofwastewater treatment plants(WWTPs),and antibiotics upstream may influence sites downstream of ***,samples from 9 effluent-receiving urban rivers(ERURs)and 12 groundwater sites were collected in Shijiazhuang City in December 2020 and April *** ERURs,8 out of 13 target quinolone antibiotics(QNs)were detected,and the total concentration of QNs in December and April were 100.6-4,398 ng/L and 8.02–2,476 ng/L,*** groundwater,all target QNs were detected,and the total QNs concentration was 1.09–23.03 ng/L for December and 4.54–170.3 ng/L for *** distribution of QNs was dissimilar between ERURs and *** QN concentrations were weakly correlated with land use types in the *** results of a positive matrix factorization model(PMF)indicated four potential sources of QNs in both ERURs and groundwater,and WWTP effluents were the main source of *** December to April,the contribution of WWTP effluents and agricultural emissions increased,while livestock activities *** value decomposition(SVD)results showed that the spatial variation of most QNs was mainly contributed by sites downstream(7.09%-88.86%)of ***,a new method that combined the results of SVD and PMF was developed for a specific-source-site risk quotient(SRQ),and the SRQ for QNs was at high level,especially for the sites downstream of *** temporal variation,the SRQ for WWTP effluents,aquaculture,and agricultural emissions ***,in order to control the antibiotic pollution,more attention should be paid to WWTP effluents,aquaculture,and agricultural emission sources for the benefit of sites downstream of WWTPs.

关键词： Source apportionment Singular value decomposition Positive matrix factorization model Quinolone antibiotics(QNs) Specific-source-site risk quotient(SRQ) WWTP effluents

Characterization of full-length transcriptome and mechanisms ofsugar accumulation in Annona squamosa fruit

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BIOCELL 2020年第4期44卷 737-750页

作者： REN FANG WEIXIONG HUANG JINYAN YAO XING LONG JI ZHANG SHUANGYUN ZHOU BIAO DENG wenzhong tang ZHENYU AN Horticultural Research Institute Guangxi Academy of Agricultural SciencesNanning530007China

Annona squamosa is a multipurpose fruit tree employed in nutritional,medicinal,and industrial *** fruit is significantly enriched in sugars,making it an excellent species to study sugar accumulation in ***,the scarcity of genomic resources hinders genetic studies in this *** study aimed at generating large-scale genomic resources in *** and deciphering the molecular basis of its high sugar ***,we sequenced and characterized the full-length transcriptome of *** fruit using PacBio *** addition,we analyzed the changes in sugar content over five fruit growth and ripening stages,and we applied RNA-sequencing technology to investigate the changes in gene expression related to sugar accumulation.A total of 783,647 circular consensus sequences were generated,from which we obtained 48,209 high-quality,full-length ***,1,838 transcription factors and 1,768 long non-coding RNAs were ***,we identified 10,400 alternative splicing events from 2,541 unigenes having on average 2–4 isoforms.A total of 15,061 simple sequence repeat(SSR)motifs were discovered and up to three primer pairs were designed for each SSR *** mainly accumulate during the ripening stage in *** of the genes involved in sugar transport and metabolism in the fruit were progressively repressed overgrowth and ripening ***,sucrose phosphate synthase involved in sucrose synthesis and more importantly,isoamylase,alpha-amylase,beta-amylase,4-alphaglucanotransferase genes involved in starch degradation displayed positive correlations with sugar accumulation in ***,we provide here a high-quality,full-length transcriptome assembly which will facilitate gene discovery and molecular breeding of *** found that starch degradation during fruit ripening was the main channel for sugar accumulation in *** fruit,and the key genes positively linked to sugar accumulation could be f

关键词： PacBio sequencing Sugar metabolism Gene expression Alternative splicing Simple sequence repeat