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Identification of thermal front dynamics in the northern Malacca Strait using ROMS 3D-model

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Journal of Oceanology and Limnology 2024年第1期42卷 41-57页

作者： Ku Nor Afiza Asnida Ku MANSOR Nur Hidayah ROSELI Poh Heng KOK Fariz Syafiq Mohamad ALI Mohd Fadzil Mohd AKHIR inst.tute of Oceanography and environment Universiti Malaysia TerengganuKuala Nerus 21030Malaysia Faculty of Science and Marine environment Universiti Malaysia TerengganuKuala Nerus 21030Malaysia

The thermal front in the oceanic system is believed to have a significant effect on biological *** an era of climate change,changes in heat regulation between the atmosphere and oceanic interior can alter the characteristics of this important *** the simulation results of the 3D Regional Ocean Modelling System(ROMS),we identified the location of thermal fronts and determined their dynamic variability in the area between the southern Andaman Sea and northern Malacca *** Single Image Edge Detection(SIED)algorithm was used to detect the thermal front from model-derived *** show that a thermal front occurred every year from 2002 to 2012 with the temperature gradient at the location of the front was 0.3°C/*** to the years affected by El Ni?o and negative Indian Ocean Dipole(IOD),the normal years(e.g.,May 2003)show the presence of the thermal front at every selected depth(10,25,50,and 75 m),whereas El Ni?o and negative IOD during 2010 show the presence of the thermal front only at depth of 75 m due to greater warming,leading to the thermocline deepening and enhanced *** May 2003,the thermal front was separated by cooler SST in the southern Andaman Sea and warmer SST in the northern Malacca *** higher SST in the northern Malacca Strait was believed due to the besieged Malacca Strait,which trapped the heat and make it difficult to release while higher chlorophyll a in Malacca Strait is due to the freshwater conduit from nearby rivers(Klang,Langat,Perak,and Selangor).Furthermore,compared to the southern Andaman Sea,the chlorophyll a in the northern Malacca Strait is easier to reach the surface area due to the shallower thermocline,which allows nutrients in the area to reach the surface faster.

关键词： regional ocean modelling system thermal front Andaman Sea Malacca Strait single image edge detection algorithm

Metal-organic frameworks on 3D interconnected macroporous sponge foams for large-scale water decontamination:A mini review

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Chinese Chemical Letters 2024年第5期35卷 77-84页

作者： Xiao-Hong Yi Chong-Chen Wang Beijing Key Laboratory of Functional Materials for Building Structure and environment Remediation School of Environment and Energy EngineeringBeijing University of Civil Engineering and ArchitectureBeijing 100044China

Water pollution caused by global population growth,urban expansion and industrialization development is one of the urgent issues that need to be addressed in the 21st *** to now,it was challenging for metal-organic frameworks(MOFs)to be used in the actual water treatment due to that the powder MOFs suffered from difficult reuse,poor water stability and easy *** is an effective strategy to immobilize MOFs powder onto porous sponge foam carriers for accomplishing large flux,facile recycling,easy processing water treatment *** this review article,the fabrication approaches and applications of different MOFs/sponge composites were highlighted,in which the fluorescence detection of pollutants,adsorption and separation of pollutants,catalytic reduction and oxidation of pollutants were ***,the future challenges and opportunities of MOF/sponge for water treatment are proposed,aiming to provide in-depth guidance for the future design and manufacture of the immobilized MOFs onto sponge foams.

关键词： Metal-organic frameworks Sponge foam Water decontamination Adsorption Catalysis

Nitrite-driven anaerobic ethane oxidation

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environmental Science and Ecotechnology 2024年第5期21卷 361-368页

作者： Cheng-Cheng Dang Yin-Zhu Jin Xin Tan Wen-Bo Nie Yang Lu Bing-Feng Liu De-Feng Xing Nan-Qi Ren Guo-Jun Xie State Key Laboratory of Urban Water Resource and environment School of EnvironmentHarbin Institute of TechnologyHarbin150090China Key Laboratory of the Three Gorges Region's Eco-environment Ministry of EducationCollege of Environment and EcologyChongqing UniversityChongqing400044China Water Innovation and Smart environment Laboratory School of Civil and Environmental EngineeringFaculty of EngineeringQueensland University of TechnologyBrisbaneQueensland4001Australia

Ethane,the second most abundant gaseous hydrocarbon in vast anoxic environments,is an overlooked greenhouse *** anaerobic oxidation of ethane can be driven by available electron acceptors such as sulfate and ***,despite nitrite being a more thermodynamically feasible electron acceptor than sulfate or nitrate,little is known about nitrite-driven anaerobic ethane *** this study,a microbial culture capable of nitrite-driven anaerobic ethane oxidation was enriched through the long-term operation of a nitrite-and-ethane-fed *** continuous operation,the nitrite removal rate and the theoretical ethane oxidation rate remained stable at approximately 25.0 mg NO_(2) eN L^(-1) d^(-1) and 11.48 mg C2H6 L^(-1) d^(-1),*** tests demonstrated that ethane is essential for nitrite removal in this microbial *** function analysis revealed that a species affiliated with a novel genus within the family Rhodocyclaceae,designated as'Candidatus Alkanivoras nitrosoreducens',may perform the nitrite-driven anaerobic ethane *** the proposed metabolic model,despite the absence of known genes for ethane conversion to ethyl-succinate and succinate-CoA ligase,'***'encodes a prospective fumarate addition pathway for anaerobic ethane oxidation and a complete denitrification pathway for nitrite reduction to *** findings advance our understanding of nitrite-driven anaerobic ethane oxidation,highlighting the previously overlooked impact of anaerobic ethane oxidation in natural ecosystems.

关键词： Anaerobic ethane oxidation Denitrification Microbial culture Fumarate addition pathway Greenhouse gas

A comparison of model choice strategies for logistic regression

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Journal of Data and Information Science 2024年第1期9卷 37-52页

作者： Markku Karhunen Built environment Solutions unit Finnish Environment Institute(Syke)Latokartanonkaari 1100790 HelsinkiFinland

Purpose:The purpose of this study is to develop and compare model choice strategies in context of logistic *** choice means the choice of the covariates to be included in the ***/methodology/approach:The study is based on Monte Carlo *** methods are compared in terms of three measures of accuracy:specificity and two kinds of sensitivity.A loss function combining sensitivity and specificity is introduced and used for a final ***:The choice of method depends on how much the users emphasize sensitivity against.*** also depends on the sample *** a typical logistic regression setting with a moderate sample size and a small to moderate effect size,either BIC,BICc or Lasso seems to be *** limitations:Numerical simulations cannot cover the whole range of data-generating processes occurring with real-world ***,more simulations are *** implications:Researchers can refer to these results if they believe that their data-generating process is somewhat similar to some of the scenarios presented in this ***,they could run their own simulations and calculate the loss ***/value:This is a systematic comparison of model choice algorithms and heuristics in context of logistic *** distinction between two types of sensitivity and a comparison based on a loss function are methodological novelties.

关键词： Model choice Logistic regression Logit regression Monte Carlo simulations Sensitivity Specificity

Atmospheric oxidation capacity and O_(3) formation in a coastal city of southeast China:Results from simulation based on four-season observation

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Journal of environmental Sciences 2024年第2期136卷 68-80页

作者： Gaojie Chen Taotao Liu Jinsheng Chen Lingling Xu Baoye Hu Chen Yang Xiaolong Fan Mengren Li Youwei Hong Xiaoting Ji Jinfang Chen Fuwang Zhang Center for Excellence in Regional Atmospheric environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Urban environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Minnan Normal University Zhangzhou 363000China College of Harbour and Coastal Engineering Jimei UniversityXiamen 361021China environmental Monitoring Center of Fujian Fuzhou 350013China

The pollution of atmospheric ozone in China shows an obvious upward trend in the past ***,the studies on the atmospheric oxidation capacity and O_(3)formation in four seasons in the southeastern coastal region of China with the rapid urbanization remain ***,a four-season field observation was carried out in a coastal city of southeast China,using an observation-based model combining with the Master Chemical Mechanism,to explore the atmospheric oxidation capacity(AOC),radical chemistry,O_(3)formation pathways and *** results showed that the average net O_(3)production rate(14.55 ppbv/hr)in summer was the strongest,but the average O_(3)concentrations in autumn was *** AOC and ROx levels presented an obvious seasonal pattern with the maximum value in summer,while the OH reactivity in winter was the highest with an average value of 22.75 sec^(-1).The OH reactivity was dominated by oxygenated VOCs(OVOCs)(30.6%-42.8%),CO(23.2%-26.8%),NO_(2)(13.6%-22.0%),and alkenes(8.4%-12.5%)in different *** photolysis dominated OH primary source on daytime in winter,while in other seasons,HONO photolysis in the morning and ozone photolysis in the afternoon contributed *** analysis indicated that O_(3)production was controlled by VOCs in spring,autumn and winter,but a VOC-limited and NOx-limited regime in summer,and alkene and aromatic species were the major controlling factors to O_(3)***,the study characterized the atmospheric oxidation capacity and elucidated the controlling factors for O_(3)production in the coastal area with the rapid urbanization in China.

关键词： Atmospheric oxidation capacity Radical chemistry Ozone production Sensitivity analysis

Characteristics and influencing factors of greenhouse gas emissions from reservoirs in the Yellow River Basin:A Meta-analysis

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Science China Earth Sciences 2024年第7期67卷 2210-2225页

作者： Shurui HUANG Peijia ZHANG Wenxiu ZHENG Jiajia ZHANG Yang LI Yuanjian WANG Enhui JIANG Shaoda LIU Xinghui XIA State Key Laboratory of Water environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 00875China Yellow River inst.tute of Hydraulic Research Yellow River Conservancy CommissionZhengzhou 450003China

Reservoir construction and operation profoundly alter the hydrological,hydrodynamic,and carbon and nitrogen cycling processes of ***,current research still lacks a systematic understanding of the characteristics of greenhouse gas(GHG)emissions from reservoirs in arid/semi-arid *** study integrates existing monitoring data to discuss the characteristics of GHG emissions from reservoirs in the Yellow River Basin and illustrate the controlling factors and underlying mechanism of these *** results indicate that while CO_(2) emission flux from reservoirs is lower than that from river channels,the emission fluxes of CH_(4) and N_(2)O are 1.9 times and 10 times those from rivers,respectively,indicating that the emission of GHG with stronger radiative effect is significantly enhanced in *** to the reservoirs in humid climates(e.g.,the Three Gorges Reservoir),reservoirs in the Yellow River Basin exhibit relatively lower emissions of CO_(2) and CH_4 due to lower organic matter concentrations,but significantly higher N_(2)O emissions due to higher nitrogen *** Carlo simulations for 237 reservoirs in the Yellow River Basin showed that total emission of the three GHGs is 3.05 Tg CO_(2)-eq yr^(-1),accounting for 0.39% of the total emission from global reservoirs and lower than the area percentage of the basin(0.53%).This study has important implications on revealing the GHG emission characteristics and control mechanisms of reservoirs in arid/semi-arid regions.

关键词： Yellow River Basin Reservoir Greenhouse gas Emission flux Water quality

Occurrence of viable but non-culturable(VBNC)pathogenic bacteria in tap water of public places

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Frontiers of environmental Science & Engineering 2024年第3期18卷 115-129页

作者： Lizheng Guo Xinyan Xiao Kassim Chabi Yiting Zhang Jingjing Li Su Yao Xin Yu China National Research inst.tute of Food and Fermentation Industries Co. Ltd.China Center of Industrial Culture CollectionBeijing 100015China Key Laboratory of Urban environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China College of environment&Ecology Xiamen UniversityXiamen 361102China

Viable but non-culturable(VBNC)bacteria have been detected in source water and effluent of drinking water treatment processes,leading to significant underestimation of viable cell *** information exists on VBNC bacteria in tap water,particularly in public *** address this gap,a comprehensive nine-month study was conducted in a major city in south-eastern China,using culture-based and quantitative PCR with propidium monoazide(PMA)dye ***-five samples were collected from five representative public places(railway station,campus,hospital,shopping mall,and inst.tution).The findings revealed that culturable bacteria represented only 0–17.51%of the viable 16S rRNA genes,suggesting that the majority of viable bacteria existed in an uncultured or VBNC ***,opportunistic pathogens such as Escherichia coli,Enterococcus faecalis,Pseudomonas aeruginosa,Salmonella sp.,and Shigella *** primarily detected as VBNC cells,with concentrations ranging from 1.03×10^(0)to 3.01×10^(3),1.20×10^(0)to 1.42×10^(2),1.32×10^(0)to 8.82×10^(0),1.00×10^(0)to 6.71×10^(1),and 2.07×10^(0)to 1.93×10^(2)cell equivalent/100 mL,*** *** was observed in tap water after prolonged stagnation,indicating potential risks associated with bacterial *** and temporal factors accounted for 17.1%and 26.0%,respectively,of the variation in tap water community structure during the sampling period,as revealed by 16S rRNA amplicon *** study provides quantitative insights into the occurrence of VBNC bacteria in tap water and highlights the need for more sensitive monitoring methods and microbial control techniques to enhance tap water safety in public locations.

关键词： VBNC Pathogenic bacteria PMA treatment Public tap water Community structure

Uncovering the dominant contribution of intermediate volatility compounds in secondary organic aerosol formation from biomass-burning emissions

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National Science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David M.Bell Tiantian Wang Houssni Lamkaddam Tianqu Cui Lu Qi Mihnea Surdu Dongyu Wang Lin Du Imad El Haddad Jay G.Slowik Andre S.H.Prevot environment Research inst.tute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(SOAs). Previous smog chamber studies found that the SOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to SOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed SOA, i.e.>2 times more than VOCs. This previously missing SOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that SOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds

Effects of the conversion of natural tropical rainforest to monoculture rubber plantations on soil hydrological processes

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Journal of Plant Ecology 2024年第2期17卷 122-133页

作者： Qiaoyan Chen Ruiyu Fu Siyuan Cheng Dong Qiao Zhongmin Hu Zijia Zhang Licong Dai Hainan Baoting Tropical Rainforest Ecosystem Observation and Research Station School of Ecology and EnvironmentHainan UniversityHaikou 570228China Center for Eco-environment Restoration Engineering of Hainan Province Hainan UniversityHaikou 570228China Hainan Ecological environment Monitoring Center Haikou 570100China

Rubber plantations have increased signifcantly under unprecedented economic growth in tropical areas,which leads to soil degradation and thereby alters soil hydrological ***,our understanding of how forest conversion affects soil hydrological processes remains ***,we collected soil samples from secondary forests(SF)and rubber plantations(RP)to determine the soil hydrological *** found the topsoil(0-20 cm)water retention in SF was higher than that of RP but displayed the contrast pattern in a deeper soil layer(20-60 cm).Meanwhile,the soil infltration rates among the two vegetation types decreased signifcantly with infltration time,with higher stable soil infltration rates in SF than those in ***,soil properties were also impacted by the forest conversion,such as the topsoil capillary porosity(CP)and total porosity(TP)in SF were higher than those of RP but contrasted in a deep soil *** comparison,the topsoil bulk density(BD)in SF was lower than that of RP,but contrasted in the deep soil layer and reached a signifcant level in the 0-10 and 40-50 cm(P<0.05).Overall,the soil water retention was mainly determined by the CP,which could explain 31.56%of the total variance in soil water retention,followed by TP(26.57%)and soil BD(26.47%),whereas soil texture exerts a weak effect on soil water ***,we can conclude that the conversion of tropical rainforest into rubber plantations may accelerate soil erosion owing to its lower topsoil water retention and soil infltration rates.

关键词： soil water retention soil infltration soil physicochemical properties rubber plantations secondary forest