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Alternate erosion and deposition in the Yangtze Estuary and the future change

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Journal of Geographical sciences 2020年第1期30卷 145-163页

作者： zhu Boyuan LI Yitian YUE yao YANG Yunping liang Enhang ZHANG Chuncai BORTHWICK Alistair G.L. School of Hydraulic engineering Changsha University of Science&TechnologyChangsha 410114China key laboratory of water-{3. {3. and water Disaster Prevention of Hunan Province Changsha 410114China School of water Resources and Hydropower engineering State Key Laboratory of Water Resources and Hydropower Engineering ScienceWuhan UniversityWuhan 430072China key laboratory of engineering {3. Tianjin Research Institute for Water Transport EngineeringMinistry of TransportTianjin 300456China The key laboratory of {3. and sediment {3. Ministry of EducationCollege of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China School of engineering The University of EdinburghThe King’s BuildingsEdinburgh EH93JLUK

The morphological changing trend of the Yangtze Estuary, the largest estuary of Asia, has become a focus of research in recent years. Based on a long series of topographic data from 1950 to 2015, this paper studied the erosion-deposition pattern of the entire Yangtze Estuary. An alternation between erosion and deposition was found during the past 65 years, which was in correspondence to the alternation between flood and dry periods identified by multi-year average duration days of high-level water flow (defined as discharge ≥ 60,000 m3/s, namely, D≥60,000) from the Yangtze River Basin. A quantitative relationship was further developed between the erosional/depositional rate of the Yangtze Estuary and the interpreting variables of yearly water discharge, D≥60,000 and yearly river sediment load, with contributing rates of 1%, 59% and 40%, respectively. Mechanism behind the alternate erosion and deposition pattern was analyzed by examining residual water surface slope and the corresponding capacity of sediment transport in flood and dry periods. In flood periods, a larger discharge results in steeper slope of residual water level which permits a greater capacity of sediment transport. Therefore, more bed materials can be washed to the sea, leading to erosion of the estuary. In contrast, flatter slope of residual water level occurs in dry periods, and deposition dominates the estuarine area due to the decreased capacity of sediment transport and the increased backwater effect of flood-tide. Coastal dynamics and estuarine engineering projects alter the local morphological changes, but slightly affect the total erosional/depositional rate of the whole estuarine region. heavy sedimentation within the Yangtze Estuary after the impoundment of the Three Gorges Dam can be attributed to the reduced occurrence frequency of flood years due to water regulation by the dam, and largely (at least 36%-52%) sourced from the sea. Deposition is still poss

关键词： Yangtze Estuary erosion and deposition alternation total sediment load evolutional trend

Iron Isotope Compositions of Natural River and Lake Samples in the Karst Area,Guizhou Province,Southwest china

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Acta Geologica Sinica(English Edition) 2011年第3期85卷 712-722页

作者： SONG Liuting LIU Congqiang WANG Zhongliang zhu Xiangkun TENG Yanguo WANG Jinsheng TANG Suohan LI Jin liang Lili College of water sciences Beijing Normal University Beijing 100875 China engineering Research Center of Groundwater Pollution Control and Remediation Ministry of Education Beijing 100875 China State key laboratory of environmental Geoc{3.mistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China

To better understand the Fe isotope characteristics of natural samples in the Karst area,the Fe isotope compositions of riverine suspended particulates,lake suspended particulates,lake {3.s,porewaters,phytoplanktons,and aerosols in the watersheds of Lake Aha（a mineralized water system）and Lake Hongfeng（a mesotrophic water system）,which are located in the Karst area, southwest china.were *** studied samples displayed a variable range betweenδ^（56）Fe=-2.03.and 0.3.‰.Aerosols and phytoplanktons have similar or slightly heavier Fe isotope compositions relative to the average of igneous *** isotope compositions of riverine Suspended Particulate Matter（SPM）were mainly affected by the types of *** particulates collected from tributaries seriously contaminated with coal mine drainages displayed negativeδ^（56）Fe values（-0.89‰to-0.3.‰）during summer,and there were significant increases ofδ^（56）Fe values in winter,except AR2,which was polluted with both coal mine drainage and sewage effluent. Characteristics of lakes have important influences on Fe isotope compositions of suspended particulates,lake {3.s,and *** epilimnetic particulate Fe of Lake Hongfeng hadδ^（56）Fe=-0.04‰to 0.13.,while lighter Fe isotope compositions were measured for particulate Fe from Lake Aha,ranging from-0.42‰to-0.09‰.{3.s collected from Hou Wu（HW）station of Lake Hongfeng have an averageδ^（56）Fe value of 0.09‰and their corresponding porewaters have lighter Fe isotope compositions,ranging from-0.57‰to-0.3.‰;no significant variations have been observed. For the liang Jiang Kou（LJK）station of Lake Aha,the content of reactive Fe and the concentration of sulfate were all *** to the reactive Fe recycling,including dissimilatory Fe reduction,adsorption, and Fe-sulfide formation,porewaters sampled near the {3. surface have been found to have aδ^（56）Fe value as low as-2.03.and an increase up to 0.12‰,with a burial depth of 10 *** contrast,a

关键词： Fe isotope composition karst riverine particulate lake particulate sediment porewater

Future climate change decreases multi-pathway but increases respiratory human health risks of PAHs across china

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National Science Open 2024年第2期3卷 128-147页

作者： Jiaao Bao Xinghui Xia Ying zhu Bingxiang Zhao Erxue Gu Yanan Liu Xiao Yun Zhenrui Zhang Nannan Xi Yong Geng Ying Xu Zhifeng Yang Derek C.G.Muir key laboratory of water and {3. {3. of ministry of education State Key Laboratory of Water Environment SimulationSchool of EnvironmentBeijing Normal UniversityBeijing 100875China State environmental Protection key laboratory of environmental health Impact Assessment of Emerging Contaminants School of Environmental Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China College of Urban and environmental sciences Laboratory for Earth Surface ProcessesSino-French Institute for Earth System SciencePeking UniversityBeijing 100871China National Climate Center China Meteorological AdministrationBeijing 100081China key laboratory for City Cluster environmental Safety and Green Development of t{3. ministry of education Institute of Environmental and Ecological EngineeringGuangdong University of TechnologyGuangzhou 510006China Aquatic Contaminants Research Division Environment and Climate Change CanadaBurlington L7S 1A1Canada

Future climate change will affect the environmental fate of hydrophobic organic contaminants(HOCs)and associated human health risks,yet the extent of these effects remains ***,we couple a high-resolution environmental multimedia model with a bioaccumulation model to study the multimedia distribution of 16 priority polycyclic aromatic hydrocarbons(PAHs),a group of HOCs,and assess future PAH-related human health risks under varying climate change scenarios over china.at a continental *** removing the effects of PAH emission changes,we find that the total PAH concentrations would decrease in the air,fresh{3.,{13.,soil,and organisms,while the high-molecular-weight PAH would increase in the air with climate warming from 1.5°C to 4°***,the multi-pathway exposure human health risks predominately influenced by dietary ingestion are expected to decrease by 1.7%–20.5%,while the respiratory risks are projected to rise by 0.2%–5.8%in the ***,the persistently high multi-pathway human health risks underscore the need for reducing future PAH emissions by 69%compared with 2009 levels in *** study demonstrates the urgency of limiting PAH emissions under future climate change for public health and highlights the importance of including the contribution of dietary ingestion in human health risk assessment.

关键词： polycyclic aromatic hydrocarbons future climate change human health risks emission reduction

Reductive immobilization and long-term remobilization of radioactive pertechnetate using bio-macromolecules stabilized zero valent iron nanoparticles

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Chinese Chemical Letters 2019年第12期30卷 2163-2168页

作者： Haodong Ji Yangmo zhu Jun Duan Wen Liu Dongye Zhao The key laboratory of {3. and sediment Science Ministry of EducationCollege of Environment Science and EngineeringPeking UniversityBeijing 100871China environmental engineering Program Department of Civil EngineeringAuburn UniversityAuburnAL 36849United States The beijing Innovation Center for engineering Science and Advanced Technology(BIC-ESAT) Peking UniversityBeijing 100871China Institute of environmental Science Taiyuan University of Science and TechnologyTaiyuan 030024China

Reductive immobilization of radioactive pertechnetate(99TcO4^-) in simulated groundwater was studied by prepared carboxymethyl cellulose(CMC) and starch stabilized zero valent iron nanoparticles(nZVI),and long-term remobilization of reduced Tc was also evaluated under anoxic and oxic *** stabilized nZVI can effectively reduce soluble 99Tc(Ⅶ) to insoluble 99 Tc(Ⅳ),and they can be easily delivered into a contaminated groundwater zone and facilitate in situ *** this study,CMCstabilized nZVI showed higher reactivity than that using starch as the *** experiments indicated that more than 99% of 99 Tc(Ⅶ)(CO=12 mg/mL) was reduced and removed from groundwater by CMC-stabilized nZVI with a CMC content of 0.2%(w/w) at a broad pH of 5-8.X-ray diffraction(XRD)and X-ray photoelectron spectroscopy(XPS) analyses further confirmed that 99Tc(Ⅶ)O4^-transformed into 99Tc(Ⅳ)O2(s).The presence of bicarbonate exhibited insignificant effect on Tc immobilization,while humic acid(HA) inhibited reaction mainly due to retardation on electron transfer and formation of Tc(IV)-HA *** interesting,the immobilized Tc(Ⅳ) remained insoluble even after 120 d under anoxic condition,while only^21 % was remobilized when exposed to ***,biomacromolecules stabilized nZVI nanoparticles could be a viable alternative for in situ remediation of radioactive contamination in groundwater.

关键词： Reductive immobilization Radionuclide Stabilized nanoparticles Zero valent iron Groundwater Technetium

Effect of Sb dopant amount on the structure and electrocatalytic capability of Ti/Sb-SnO_2 electrodes in the oxidation of 4-chlorophenol

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Journal of environmental sciences 2007年第11期19卷 1380-1386页

作者： KONG Jiang-tao SHI Shao-yuan zhu Xiu-ping NI Jin-ren key laboratory of water and {3. {3. Ministry of Education of China department of environmental engineering Peking University Beijing 100871 China State key laboratory of Biochemical {3. Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

Ti/Sb-SnO2 anodes were prepared by thermal decomposition to examine the influence of the amount of Sb dopant on the structure and electrocatalytic capability of the electrodes in the oxidation of 4-chlorophenol. The physicochemical properties of the Sb-SnO2 coating were markedly influenced by different amounts of Sb dopant. The electrodes, which contained 5% Sb dopant in the coating, presented a much more homogenous surface and much smaller mud-cracks, compared with Ti/Sb-SnO2 electrodes containing 10% or 15% Sb dopant, which exibited larger mud cracks and pores on the surface. However, the main microstructure remained unchanged with the addition of the Sb dopant. No new crystal phase was observed by X-ray diffraction （XRD）. The electrochemical oxidation of 4-chlorophenol on the Ti/SnO2 electrode with 5% Sb dopant was inclined to electrochemical combustion; while for those containing more Sb dopant, intermediate species were accumulated. The electrodes with 5% Sb dopant showed the highest efficiency in the bulk electrolysis of 4-chlorophenol at a current density of 20 mA/cm^2 for 180 min; and the removal rates of 4-chlorophenol and COD were 51.0% and 48.9%, respectively.

关键词： 4-chlorophenol cyclic voltammogram electrochemical oxidation Sb dopant Ti/Sb-SnO2 electrode

Effects of seasonal climatic variability on several toxic contaminants in urban lakes: Implications for the impacts of climate change

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Journal of environmental sciences 2014年第12期26卷 2369-2378页

作者： Qiong Wu Xinghui Xia Xinli Mou Baotong zhu Pujun Zhao Haiyang Dong State key laboratory of water Environment Simulation Key Laboratory of Water and Sediment Sciences of Ministry of EducationSchool of Environment Beijing Normal University School of Chemical and environmental engineering Chongqing Three Gorges University

Climate change is supposed to have influences on water quality and ecosystem. However, only few studies have assessed the effect of climate change on environmental toxic contaminants in urban lakes. In this research, response of several toxic contaminants in twelve urban lakes in {3.,{3. to the seasonal variations in climatic factors was studied. Fluorides, volatile phenols, arsenic, selenium, and other water quality parameters were analyzed monthly from2009 to 2012. Multivariate statistical methods including principle component analysis, cluster analysis, and multiple regression analysis were performed to study the relationship between contaminants and climatic factors including temperature, precipitation, wind speed, and sunshine duration. Fluoride and arsenic concentrations in most urban lakes exhibited a significant positive correlation with temperature/precipitation, which is mainly caused by rainfall induced diffuse pollution. A negative correlation was observed between volatile phenols and temperature/precipitation, and this could be explained by their enhanced volatilization and biodegradation rates caused by higher temperature. Selenium did not show a significant response to climatic factor variations, which was attributed to low selenium contents in the lakes and soils. Moreover, the response degrees of contaminants to climatic variations differ among lakes with different contamination levels. On average, temperature/precipitation contributed to 8%, 15%, and 12% of the variations in volatile phenols, arsenic, and fluorides,respectively. {3. is undergoing increased temperature and heavy rainfall frequency during the past five decades. This study suggests that water quality related to fluoride and arsenic concentrations of most urban lakes in {3. is becoming worse under this climate change trend.

关键词： Climatic variations Urban lakes Volatile phenols Arsenic Fluorides Selenium water quality

调蓄河湖群菹草( Potamogeton crispus L.)功能性状特征及其与环境因子的关系

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生态学报 2020年第6期40卷 1990-1998页

作者：朱天顺王丽虹何亮蒋万祥申恒伦陈静苏朋韩庆香曹特潘保柱枣庄学院生命科学学院枣庄277160 南昌大学鄱阳湖环境与资源利用教育部重点实验室南昌330031 中国科学院水生生物研究所淡水生态与生物技术国家重点实验室武汉430072 西安理工大学水利水电学院西安710048

调水工程引起的多环境因子关联变化对沉水植物群落的影响机制有待深入探讨。以南水北调东线工程调蓄河湖群中菹草种群为研究对象,分析了京杭运河(YH)、高邮湖(GY)、洪泽湖(HZ)、骆马湖(LM)、南四湖上级湖(NS1)、南四湖下级湖(NS2)和东平... 详细信息

调水工程引起的多环境因子关联变化对沉水植物群落的影响机制有待深入探讨。以南水北调东线工程调蓄河湖群中菹草种群为研究对象,分析了京杭运河(YH)、高邮湖(GY)、洪泽湖(HZ)、骆马湖(LM)、南四湖上级湖(NS1)、南四湖下级湖(NS2)和东平湖(DP)7个调蓄河湖中菹草个体功能性状特征及其与环境因子间的关系。结果表明:(1)除高锰酸盐指数(CODMn)、浊度(Tur)和底泥有机质含量(So)外,总氮(TN)、硝氮(NO3.N)、氨氮(NH4-N)、总磷(TP)、正磷酸盐(PO4-P)、硅酸盐(SiO4-Si)、叶绿素a(Chla)、总溶解性固体(TDS)、透明度(SD)、消光系数(K)、水温(T)、电导率(Cond)、酸碱度(pH)、溶解氧(DO)和底泥含水率(Sw)在河湖间差异达到了极显著水平;(2)菹草株高、茎分支数、茎节数、茎节长、茎直径、相对茎长、叶片数、叶厚、叶长、叶宽、叶面积、比叶面积、株重、茎重、叶重、茎叶比、茎干物质比、叶干物质比在河湖间差异极显著;(3.河湖群内菹草种群18个功能性状中,按变异系数从小到大依次为:叶宽、茎直径、叶长、茎干物质比、叶干物质比、叶面积、株高、茎节长、相对茎长、茎叶比、叶厚、茎节数、茎重、叶片数、株重、比叶面积、叶重、茎分支数;7个调蓄河湖间,按照所有性状变异系数平均值从大到小排序依次为:南四湖下级湖、洪泽湖和京杭运河、高邮湖、东平湖、南四湖上级湖、骆马湖;(4)环境因子共解释了功能性状方差变异的49.43.;叶性状主要受营养因子(TN、NO3.N、SiO4-Si)影响;茎性状与光照因子(Chla和SD)密切相关;底泥因子(So)对茎叶生物量分配起主要作用。

关键词：功能性状环境因子菹草调蓄河湖南水北调

湖泊生态系统稳态转换驱动因子判定方法研究进展

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水生态学杂志 2017年第1期38卷 1-9页

作者：赵磊刘永李玉照朱翔邹锐宋迪云南省环境科学研究院云南省高原湖泊流域污染过程与管理重点实验室昆明650034 北京大学环境科学与工程学院水沙科学教育部重点实验室北京100871

湖泊生态系统会在长期的人为胁迫和短期的强扰动下发生稳态转换,灾变性稳态转换将会导致湖泊水环境在短时间内急剧恶化,进而延缓和加大治理的进程及成本。探求浅水湖泊稳态转换驱动因子是科学合理确定湖泊管理策略的关键所在,现有的驱... 详细信息

湖泊生态系统会在长期的人为胁迫和短期的强扰动下发生稳态转换,灾变性稳态转换将会导致湖泊水环境在短时间内急剧恶化,进而延缓和加大治理的进程及成本。探求浅水湖泊稳态转换驱动因子是科学合理确定湖泊管理策略的关键所在,现有的驱动因子判定方法主要有实验观测、统计分析和模型模拟。实验观测缺乏对生态系统整体的判断,仅采用观测数据并不能得出导致稳态转换确切的原因和效应;统计分析难以对未来作出预警;模型模拟可有效规避上述2种方法存在的问题,特别是机理模型是今后分析稳态转换的主要方法。有必要加强统计分析与模型模拟的结合、生态模型与传统水质水动力模型耦合等方面的研究工作。

关键词：湖泊生态系统稳态转换驱动因子

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区域性湖泊营养盐基准的适用性研究

环境科学学报 2018年第7期38卷 2545-2553页

作者：梁中耀陈会丽任婷玉伊璇朱翔刘永郭怀成北京大学环境科学与工程学院水沙科学教育部重点实验室北京100871 水利部国际经济技术合作交流中心北京100053 云南省环境监测中心站昆明650000

营养盐基准是湖泊富营养化控制与管理的基础,目前多采用以生态分区为基础的基准确定方法.由于同一生态分区内湖泊间的差异性,对区域性湖泊营养盐基准的适用性需要做进一步的探究.本研究提出了基于响应关系的聚类方法(RCA),包括:(1)基于... 详细信息

营养盐基准是湖泊富营养化控制与管理的基础,目前多采用以生态分区为基础的基准确定方法.由于同一生态分区内湖泊间的差异性,对区域性湖泊营养盐基准的适用性需要做进一步的探究.本研究提出了基于响应关系的聚类方法(RCA),包括:(1)基于线性混合效应模型和平均绝对百分误差的层次聚类过程;(2)基于赤池信息准则(AIC)的模型选择过程.基于长时间数据的可得性,选择我国云贵湖区和东部湖区作为对象,采用RCA对叶绿素a与营养盐(总氮和总磷)之间的响应关系进行分析.结果发现,区域性响应关系对应的AIC值均为最高,模型权重均小于0.001,且可能导致生态谬误;表明区域性湖泊营养盐基准不能完全适用于生态分区内全部湖泊.该研究可为我国湖泊营养盐基准的空间尺度确定和浓度限值识别提供参考.

关键词：生态分区营养盐基准基于响应关系的聚类方法层次聚类线性混合效应模型