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Terrestrial input and nutrient change reflected by sediment records of the Changjiang River Estuary in recent 80 years

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Acta Oceanologica Sinica 2015年第2期34卷 27-35页

作者： LI Junlong ZHENG Binghui HU Xupeng WANG Yiming DING Ye LIU Fang College of Water Sciences Beijing Normal University State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences State environmental Protection Key Laboratory of Quality Control in environmental monitoring China National Environmental Monitoring Center Zhoushan Marine ecological environmental monitoring Station

A variety of environmental problems have been observed in the Changjiang River Estuary and adjacent coastal area, including eutrophication, harmful algal blooms（HABs）, and hypoxia in recent decades. Application of sedimentary biogenic element indicators on the study of paleoenvironment can reconstruct environmental evolution history of waters. Two 210Pb-dated cores were collected from the Changjiang River Estuary（S3） and adjacent coastal area（Z13）, and total organic carbon（TOC）, total nitrogen（TN）, biogenic silicon（BSi）, total phosphorus（TP） and phosphorus（P） species were analyzed. Three stages of environmental changes are deduced by the nutrient sedimentary records. First, nutrient concentration increased rapidly since the 1950 s, which attributed to agriculture development and overused chemical fertilizers. Second, nutrient concentration kept high and primary production began to promote during the 1960 s to 1980 s, while diatom abundance and proportion began to decline since the 1970 s, accompanied by reduced 23 Si O- concentration and flux from the river. Third, due to several dams and bridges constructed, river runoff and coastal hydrodynamic conditions reduced to a certain extent since the 1990 s, which aggravated the unbalance in nutrient structure. Multi-nutrient proxies in sediment can reflect the natural environm-ental changes as well as influence of human activities.

关键词： biogenic elements phosphorus species sediment cores Changjiang River Estuary

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Effects of Ulva prolifera dissipation on the offshore environment based on remote sensing images and field monitoring data

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Acta Oceanologica Sinica 2023年第6期42卷 112-120页

作者： Longxiao Zheng Mengquan Wu Jie Zhao Shaopeng Luan Dongliang Wang Wei Jiang Mingyue Xue Jiayan Liu Yating Cui College of Resources and environmental Engineering Ludong UniversityYantai 264039China Yantai Geographic Information center Yantai 264025China Yantai Marine Environment monitoring and Forecasting center Yantai 264040China

Outbreaks of Ulva prolifera have continued in the South Yellow Sea of China(SYS)since 2007,becoming a serious marine ecological *** amounts of *** drift to the coast of the Shandong Peninsula to dissipate under the action of southeast monsoons and ocean surface *** causes serious harm to the ecological environment and economic activities of coastal *** investigate the impact of *** dissipation,this study extracted the spatiotemporal distribution of *** in the SYS from 2012 to 2020 based on the Google Earth *** outbreak cycle of *** was determined by fitting analysis of outbreak time and coverage area through *** study also looked at the effect of *** dissipation on water quality through field monitoring *** results showed that the growth curve of the *** has a significant Gaussian *** *** dissipates in Haiyang,China,in July and August every year and affects the offshore *** quality parameters of seawater at different depths had significant differences after the *** *** in pH,chemical oxygen demand,nitrite nitrogen,nitrate nitrogen,ammonia nitrogen,chlorophyll a,total phosphorus,and suspended solids were more significant in surface seawater than in deeper *** in the concentrations of dissolved oxygen and total nitrogen were more significant in the deep seawater(1.63 and 1.1 times higher than those in the surface seawater,respectively).The dissipation of *** releases a large amount of carbon and nitrogen into the seawater,which provides rich nutrients for phytoplankton and may cause secondary disasters such as red *** findings are useful for further understanding the rules of *** dissipation,as well as preventing and controlling green tide disasters.

关键词： Ulva prolifera dissipation South Yellow Sea Google Earth Engine water quality remote sensing

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Spatial and diel variations of the prokaryotic community in the Phaeocystis globosa blooms area of Beibu Gulf,China

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Acta Oceanologica Sinica 2022年第12期41卷 87-97页

作者： Cheng He Sha Xu Shuqun Song Caiwen Li North China Sea environmental monitoring center State Oceanic AdministrationQingdao 266033China Key Laboratory of ecological Prewarning Protection and Restoration of Bohai SeaMinistry of Natural ResourcesQingdao 266033China Key Laboratory of Marine Ecology and environmental Sciences Chinese Academy of SciencesQingdao 266071China Marine Ecology and environmental Science Laboratory Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China Shaanxi Provincial Academy of environmental Science Xi’an 710061China

While prokaryotes play key roles in nutrient cycling and energy flow during Phaeocystis globosa blooms,the information on the spatial and diel temporal distribution of the prokaryotic community during Phaeocystis blooms remains *** January 2019,we used high-throughput sequencing of the 16S rRNA gene to explore the spatial and diel variations of particle-attached(PA)and free-living(FL)prokaryotic communities during the blooming phase of *** in Beibu Gulf,Guangxi,*** results suggested a significant spatial variation pattern in the horizontal distribution of prokaryotic communities,while there was no significant difference in the vertical *** spatial distance and environmental variables shaped the horizontal distribution of the prokaryotic community structure,while environmental variables,particularly the abundance of *** colony and Chl a,showed more significant influence and were closely related to the structure and variation of the prokaryotic *** vertical mixing of the water column disrupted the vertical structure heterogeneity of the prokaryotic community in *** were significant differences in the diel samples of PA prokaryotic communities,but not in the FL prokaryotic ***,ammonium and the abundance of *** colony were the key environmental variables impacting the diel variations of prokaryotic communities over the sampling *** present study provided valuable information to depict the spatial-temporal variations of the microbial community and its association with environmental parameters during *** bloom in the tropical gulf.

关键词： algal bloom 16S rRNA genes prokaryotic community diversity spatial patterns diel distribution

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中国碳收支:1980~2021年

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Science Bulletin 2024年第1期69卷 114-124页

作者：夏晓圣任培阳王旭辉刘丹陈修治丹利何斌何洪林居为民梁敏琪陆星劼彭静覃章才夏江周郑博魏静乐旭于贵瑞朴世龙袁文平 School of Atmospheric Sciences Guangdong Province Data Center of Terrestrial and Marine Ecosystems Carbon CycleSun Yat-sen UniversityZhuhai 510245China Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100091China State Key Laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Earth Surface Processes and Resource Ecology College of Global Change and Earth System ScienceBeijing Normal UniversityBeijing 100875China Synthesis Research center of China’s Ecosystem Research Network Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China International Institute for Earth System Science Nanjing UniversityNanjing 210023China Tianjin Key Laboratory of Water Resources and Environment Tianjin Normal UniversityTianjin 300387China Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhen 518055China Jiangsu Key Laboratory of Atmospheric Environment monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China

As one of the world's largest emitters of greenhouse gases,China has set itself the ambitious goal of achieving carbon peaking and carbon ***,it is crucial to quantify the magnitude and trend of sources and sinks of atmospheric carbon dioxide(CO_(2)),and to monitor China's progress toward these *** state-of-the-art datasets and models,this study comprehensively estimated the anthropogenic CO_(2)emissions from energy,industrial processes and product use,and waste along with natural sources and sinks of CO_(2)for all of China during *** recognize the differences among various methods of estimating greenhouse emissions,the estimates are compared with China's National Greenhouse Gas Inventories(NGHGIs)for 1994,2005,2010,2012,and *** CO_(2)emissions in China have increased by 7.39 times from 1980 to 12.77 Gt CO_(2)a^(-1)in *** benefiting from ecological projects(e.g.,Three Norths Shelter Forest System Project),the land carbon sink in China has reached 1.65 Gt CO_(2)a^(-1)averaged through 2010-2021,which is almost 15.81 times that of the carbon sink in the *** average,China's terrestrial ecosystems offset 14.69%±2.49%of anthropogenic CO_(2)emissions through *** provincial-level administrative regions of China,Xizang and Qinghai,have achieved carbon neutrality according to our estimates,but nearly half of the administrative regions of China have terrestrial carbon sink offsets of less than 10%of anthropogenic CO_(2)*** study indicated a high level of consistency between NGHGIs and various datasets used for estimating fossil CO_(2)emissions,but found notable differences for land carbon *** estimates of the terrestrial carbon sinks of NGHGIs urgently need to be verified with process-based models which integrate the comprehensive carbon cycle processes.

关键词： CO_(2)emission Land carbon sink China Carbon neutrality Carbon budget

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Comparison of short-term toxicity of 14 common phycotoxins(alone and in combination)to the survival of brine shrimp Artemia salina

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Acta Oceanologica Sinica 2023年第2期42卷 134-141页

作者： Yuting Zhang Shanshan Song Bin Zhang Yang Zhang Miao Tian Ziyi Wu Huorong Chen Guangmao Ding Renyan Liu Jingli Mu Institute of Oceanography College of Geography and OceanographyMinjiang UniversityFuzhou350108China Fuzhou Institute of Oceanography Fuzhou350108China Department of Marine Chemistry National Marine Environmental Monitoring CenterDalian116023China Fujian Marine Environment and Fishery Resource monitoring center Fuzhou350003China

Toxic harmful algal blooms(HABs)can cause deleterious effects in marine organisms,threatening the stability of marine *** is well known that different strains,natural populations and growth conditions of the same toxic algal species may lead to different amount of phycotoxin production and the ensuing *** fully assess the ecological risk of toxic HABs,it is of great importance to investigate the toxic effects of phycotoxins in marine *** this study,the short-term toxicity of 14 common phycotoxins(alone and in combination)in the marine zooplankton Artemia salina was *** 48 h LC_(50)of the 14 phycotoxins varied from 0.0193µg/mL to 2.415µg/*** most potent phycotoxin was azaspiracids-3(AZA3;with a LC_(50)of 0.0193µg/mL),followed by azaspiracids-2(AZA2;0.0226µg/mL),pectenotoxin-2(PTX2;0.0460µg/mL)and dinophysistoxin-1(DTX1;0.0818µg/mL).For the binary exposure,okadaic acid(OA)induced potential additive effects with DTX1,probably due to their similar structure(polyether fatty acid)and mode of action(attacking the serine/threonine phosphoprotein phosphatases).On the other hand,OA showed potential antagonistic effects with PTX2,which might be accounted for by their activation on the detoxification activity of cytochrome P450 *** addition,DTX1 induced potential synergetic effects with saxitoxin(STX),yessotoxin(YTX)or PTX2,suggesting the hazard potency of the mixtures of DTX1 and other phycotoxins(like STX,YTX and PTX2)with regard to the ecological *** results provide valuable toxicological data for assessing the impact of phycotoxins on marine planktonic species and highlight the potential ecological risk of toxic HABs in marine ecosystems.

关键词： LC_(50) harmful algal blooms binary exposure ecological risk

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Exploration of the formation mechanism and source attribution of ambient ozone in Chongqing with an observation-based model

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Science China Earth Sciences 2018年第1期61卷 23-32页

作者： SU Rong LU KeDing YU JiaYan TAN ZhaoFeng JIANG MeiQing LI Jing XIE ShaoDong WU YuSheng ZENG LiMin ZHAI ChongZhi ZHANG YuanHang State Key Joint Laboratory of environmental Simulation and Pollution Control College of Environmental Sciences and Engineering Peking University Beijing 100871 China ecological and environmental monitoring center ofChongqing Chongqing 401147 China

An intensive field campaign was conducted in Chongqing during the summer of 2015 to explore the formation mechanisms of ozone pollution. The sources of ozone, the local production rates, and the controlling factors, as well as key species of volatile organic compounds(VOCs), were quantified by integrating a local ozone budget analysis, calculations of the relative incremental reactivity, and an empirical kinetic model approach. It was found that the potential for rapid local ozone formation exists in Chongqing. During ozone pollution episodes, the ozone production rates were found to be high at the upwind station Nan Quan, the urban station Chao Zhan, and the downwind station Jin-Yun Shan. The average local ozone production rate was 30×10^(-9) V/V h^(-1) and the daily integration of the produced ozone was greater than 180×10^(-9) V/V. High ozone concentrations were associated with urban and downwind air masses. At most sites, the local ozone production was VOC-limited and the key species were aromatics and alkene, which originated mainly from vehicles and solvent usage. In addition, the air masses at the northwestern rural sites were NO_x-limited and the local ozone production rates were significantly higher during the pollution episodes due to the increased NOx concentrations. In summary, the ozone abatement strategies of Chongqing should be focused on the mitigation of VOCs. Nevertheless, a reduction in NO_x is also beneficial for reducing the regional ozone peak values in Chongqing and the surrounding areas.

关键词：臭氧重庆光化学没有 x VOCs Sensitivity 分析相对增长反应 EKMA

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Spatiotemporal Evolution of the Dongting Lake Beach in recent 90 years

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Journal of Earth Science 2023年

作者： Shuchen Yu Yongzhong Zhang Qiuhua He Xiaoyan Jin Kun Li Weiqi Luo Deqing Yu Hunan Key Laboratory of Remote Sensing monitoring of ecological Environment in Dongting Lake Area Hunan Natural Resources Affairs center

Using historical topographic maps and aerospace remote sensing data since the 1930s， this study investigated the spatial and temporal evolution of Dongting Lake beach. The evolution characteristics of the beaches in different regions and the related formation mechanism were also analyzed. The results showed that Dongting Lake beach expanded from 1622.17 km2in 1938 to 1962.28 km2in 2018. With the addition of 980.96 km2of reclaimed high bay beach， the beach area increased by 1321.07 km2. However， the change process fluctuated somewhat rather than continuously increasing. Substantial expansion of the beach area occurred during 1938–1948 and 1958–1998， while slow contraction of the beach area occurred during 1948–1958 and 1998–2018. Dongting Lake beach was dominated by terrigenous debris， the sedimentary types included lacustrine deposits， river alluvial deposits， floodplain and main channel deposits， and river-lake interaction deposits. The rapid expansion occurred in the estuary delta of the east branch of the Ouchi River， which advanced 38.55 km from the estuary toward the lake over the past 90 years. The causes of the changes in the beach included beach reclamation， sediment changes， and lake sand mining. 70 embankments (covering 2057.77 km2) have been enclosed in the Dongting Lake area since 1930s， of which the high bay beach covered an area of 980.96 km2. The amount of sediment deposited in Dongting Lake has reached 230857×104m3since 1950s， which is equivalent to an average deposition height of 0.85m on the lake’s bottom. The mining of lake sand caused the beach to shrink， and the proportion of the beach area decreased from 77.18% in 1998 to 72.60% in 2018. The results of this study provided objective data for protecting the lakeshore’s ecosystem and biodiversity and supporting the ecological restoration and environmental protection of the Yangtze River Basin.

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The Derivation of Nutrient Criteria for the Adjacent Waters of Yellow River Estuary in China

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Journal of Ocean University of China 2022年第5期21卷 1227-1236页

作者： LOU Qi ZHANG Xueqing ZHAO Bei CAO Jing LI Zhengyan College of environmental Science and Engineering Ocean University of ChinaQingdao 266100China North China Sea environmental monitoring center State Oceanic AdministrationQingdao 266033China Key Laboratory of Marine environmental Science and Ecology Ministry of EducationQingdao 266100China

ecological protection and high-quality development of the Yellow River basin are becoming part of the national strategy in recent *** Yellow River Estuary has been seriously affected by human ***,it has been severely polluted by the nitrogen and phosphorus from land sources,which have caused serious eutrophication and harmful algal *** criteria,however,was not developed for the Yellow River Estuary,which hindered nutrient management measures and eutrophication risk assessment in this key ecological function zone of *** on field data during 2004-2019,we adopted the frequency distribution method,correlation analysis,Linear Regression Model(LRM),Classification and Regression Tree(CART)and Nonparametric Changepoint Analysis(nCPA)methods to establish the nutrient criteria for the adjacent waters of Yellow River *** water quality criteria of dissolved inorganic nitrogen(DIN)and soluble reactive phosphorus(SRP)are recommended as 244.0μg L^(−1) and 22.4μg L^(−1),*** is hoped that the results will provide scientific basis for the formulation of nutrient standards in this important estuary of China.

关键词： water quality criteria nutrient Yellow River Estuary frequency distribution classification and regression tree eutro-phication

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Photodegradation of hydroxyfluorenes in ice and water: A comparison of kinetics, effects of water constituents, and phototransformation by-products

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Journal of environmental Sciences 2023年第2期124卷 139-145页

作者： Linke Ge Shengkai Cao Crispin Halsall Junfeng Niu Dongxiao Bai Guangkai He Peng Zhang Hongrui Ma School of environmental Science and Engineering Shaanxi University of Science&TechnologyXi’an 710021China Lancaster Environment Centre Lancaster UniversityLancaster LA14YQUK State environmental Protection Key Laboratory of Coastal Ecosystem National Marine Environmental Monitoring CenterDalian 116023China

The photochemical behavior of organic pollutants in ice is poorly studied in comparison to aqueous *** we report a detailed comparison of ice and aqueous photodegradation of two representative OH-PAHs,2-hydroxyfluorene(2-OHFL)and 9-hydroxyfluorene(9-OHFL),which are newly recognized contaminants in the wider environment including colder ***,their photodegradation kinetics were clearly influenced by whether they reside in ice or *** the same simulated solar irradiation(λ>290 nm),OHFLs photodegraded faster in ice than in equivalent aqueous solutions and this was attributed to the specific concentration effect caused by ***,the presence of dissolved constituents in ice also influenced photodegradation with 2-OHFL phototransforming the fastest in‘seawater’ice(k=(11.4±1.0)×10^(−2) min^(−1))followed by‘pure-water’ice((8.7±0.4)×10^(−2) min^(−1))and‘freshwater’ice((8.0±0.7)×10^(−2) min^(−1)).The presence of dissolved constituents(specifically Cl^(−),NO_(3)^(−),Fe(Ⅲ)and humic acid)influences the phototransformation kinetics,either enhancing or suppressing phototransformation,but this is based on the quantity of the constituent present in the matrixes,the specific OHFL isomer and the matrix type(e.g.,ice or aqueous solution).Careful derivation of key photointermediates was undertaken in both ice and water samples using tandem mass *** phototransformation exhibited fewer by-products and‘simpler’pathways giving rise to a range of hydroxylated fluorenes and hydroxylated fluorenones in *** results are of importance when considering the fate of PAHs and OH-PAHs in cold regions and their persistence in sunlit ice.

关键词： Ice photochemistry Hydroxyfluorene Photodegradation Kinetics Water constituents Intermediates

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Temporal-spatial risk assessment of COVID-19 under the influence of urban spatial environmental parameters:The case of Shenyang city

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Building Simulation 2023年第5期16卷 683-699页

作者： Sui Li Zhe Li Yixin Dong Tiemao Shi Shiwen Zhou Yumeng Chen Xun Wang Feifei Qin School of Architecture and Planning Shenyang Jianzhu UniversityShenyangLiaoning 110168China Institute of ecological Urban Planning and Green Building Shenyang Jianzhu UniversityShenyangLiaoning 110168China School of Architecture Tianjin UniversityTianjin 300072China Institute of Spatial Planning and Design Shenyang Jianzhu UniversityShenyangLiaoning 110168China School of Science Shenyang Jianzhu UniversityShenyangLiaoning 110168China

Respiratory infection is the main route for the transmission of coronavirus pneumonia,and the results have shown that the urban spatial environment significantly influences the risk of *** on the Wells-Riley model of respiratory infection probability,the study determined the human respiratory-related parameters and the effective influence range;extracted urban morphological parameters,assessed the ventilation effects of different spatial environments,and,combined with population flow monitoring data,constructed a method for assessing the risk of Covid-19 respiratory infection in urban-scale grid *** the empirical study in Shenyang city,a severe cold region,urban morphological parameters,population size,background wind speed,and individual behavior patterns were used to calculate the distribution characteristics of temporal and spatial concomitant risks in urban areas grids under different *** results showed that the correlation between the risk of respiratory infection in urban public spaces and the above variables was *** exposure time had the greatest degree of influence on the probability of respiratory infection risk among the *** the same time,the change in human body spacing beyond 1 m had a minor influence on the risk of *** the urban morphological parameters,building height had the highest correlation with the risk of infection,while building density had the lowest *** actual point distribution of the epidemic in Shenyang from March to April 2022 was used to verify the evaluation *** overlap rate between medium or higher risk areas and actual cases was 78.55%.The planning strategies for epidemic prevention and control were proposed for the spatial differentiation characteristics of different risk *** research results can accurately classify the risk level of urban space and provide a scientific basis for the planning response of epidemic prevention and control and the sa

关键词： COVID-19 virus infection rate GIS data simulations urban morphological parameters analysis infection risk assessment epidemic containment planning

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