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Emission patterns of biogenic volatile organic compounds from dominant forest species in Beijing, China

Journal of Environmental Sciences 2020年第9期32卷 73-81页

作者： Xiaoxi Jing Xiaoxiu Lun Chong Fan Weifang Ma College of Environmental Science and Engineering Beijing Forestry University Beijing 100083 China

Biogenic volatile organic compounds(BVOC s) have significant effects on atmospheric chemistry,ozone formation and secondary organic aerosol formation.Considering few investigations about BOVCs emissions in north China where is facing serious air pollution in recent years,emissions of various BVOCs from 24 dominant forest species in Beijing were measured from June to September in 2018,using a dynamic headspace sampling method.More than one hundred BVOCs in the collected samples were identified by using an automatic thermal desorption-gas chromatography/mass spectrometry,and their emission rates based on leaf biomass were calculated.Isoprene and monoterpenes were verified to be the dominant BVOCs emitted from the tree species,accounting for more than 50% of the total BVOCs.Generally,broad-leaved species displayed high isoprene emission rates,especially the Platanus occidentalis(21.36μg/(g·hr)),Robinia pseudoacacia(11.55μg/(g·hr)),and Lonicera maackii(9.17μg/(g·hr)),while coniferous species emitted high rates of monoterpenes,such as Platycladus orientalis(27.18μg/(g·hr)),Pinus griffithii(23.11μg/(g·hr)),and Pinus armandii(7.42μg/(g·hr)).High emission rates of monoterpenes from the broad-leaved species of Buxus megistophylla(13.07μg/(g·hr)) and Ligustrum uicaryi(5.74μg/(g·hr)),and high isoprene emission rate from the coniferous tree of Taxus cuspidata(5.86μg/(g·hr)) were also observed.The emission rates of sesquiterpenes from each tree were usually 10-100 times smaller than those of isoprene and monoterpenes.Additionally,relatively high emission rates of oxygenated volatile organic compounds and other alkenes than isoprene and monoterpenes were also found for several tree species.

关键词： pollution volatile forest

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CH_4 emission and conversion from A^2O and SBR processes in full-scale wastewater treatment plants

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Journal of Environmental Sciences 2014年第1期26卷 224-230页

作者： Yan Liu Xiang Cheng Xiaoxiu Lun Dezhi Sun College of Environmental Science and Engineering Beijing Forestry University

Wastewater treatment systems are important anthropogenic sources of CH4 emission. A full-scale experiment was carried out to monitor the CH4 emission from anoxic/anaerobic/oxic process （A2O） and sequencing batch reactor （SBR） wastewater treatment plants （WWTPs） for one year from May 2011 to April 2012. The main emission unit of the A2O process was an oxic tank, accounting for 76.2% of CH4 emissions; the main emission unit of the SBR process was the feeding and aeration phase, accounting for 99.5% of CH4 emissions. CH4 can be produced in the anaerobic condition, such as in the primary settling tank and anaerobic tank of the A2O process. While CH4 can be consumed in anoxic denitrification or the aeration condition, such as in the anoxic tank and oxic tank of the A2O process and the feeding and aeration phase of the SBR process. The CH4 emission flux and the dissolved CH4 concentration rapidly decreased in the oxic tank of the A2O process. These metrics increased during the first half of the phase and then decreased during the latter half of the phase in the feeding and aeration phase of the SBR process. The CH4 oxidation rate ranged from 32.47% to 89.52% （mean： 67.96%） in the A2O process and from 12.65% to 88.31% （mean： 47.62%） in the SBR process. The mean CH4 emission factors were 0.182 g/ton of wastewater and 24.75 g CH4/（person.year） for the A2O process, and 0.457 g/ton of wastewater and 36.55 g CH4/（person.year） for the SBR process.

关键词： CH4 emission production and consumption wastewater treatment plant A2O SBR

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Reviews of emission of biogenic volatile organic compounds(BVOCs) in Asia

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Journal of Environmental Sciences 2020年第9期32卷 266-277页

作者： Xiaoxiu Lun Ying Lin Fahe Chai Chong Fan Hong Li Junfeng Liu College of Environmental Science and Engineering Beijing Forestry UniversityBeijing 100083China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China

Biogenic volatile organic compounds(BVOCs) in the atmosphere play important roles in the formation of ground-level ozone and secondary organic aerosol(SOA) in global scale and also in regional scale under some condition due to their large amount and relatively higher reactivity.In places with high plant cover in the tropics and in China where air pollution is serious,the effect of BVOCs on ozone and secondary organic aerosols is strong.The present research aims to provide a comprehensive review about the emission rate,emission inventory, research methods,the influencing factors of BVOCs emissions,as well as their impacts on atmospheric environment quality and human health in recent years in Asia based on the summary and analysis of literatures.It is suggested to use field direct measurement method to obtain the emission rate and model method to calculate the emission amount.Several recommendations are given for future investigation and policy development on BVOCs emission.

关键词： BVOCs pollution volatile

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Reversibility of the structure and dewaterability of anaerobic digested sludge

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Journal of Environmental Sciences 2016年第4期28卷 178-186页

作者： Yiqi Sheng Yili Wang Wei Hu Xu Qian Huaili Zheng Xiaoxiu Lun College of Environmental Science and Engineering Beijing Key Lab for Source Control Technology of Water PollutionBeijing Forestry University College of Urban Construction and Environmental Engineering Chongqing University

The reversibility of the structure and dewaterability of broken anaerobic digested sludge（ADS）is important to ensure the efficiency of sludge treatment or management processes.This study investigated the effect of continuous strong shear（CSS）and multipulse shear（MPS）on the zeta potential,size（median size,d（50））,mass fractal dimension（DF）,and capillary suction time（CST）of ADS aggregates.Moreover,the self-regrowth（SR）of broken ADS aggregates during slow mixing was also analyzed.The results show that raw ADS with d（50） of 56.5μm was insensitive to CSS–SR or MPS–SR,though the size slightly decreased after the breakage phase.For conditioned ADS with d（50） larger than 600μm,the breakage in small-scale surface erosion changed to large-scale fragmentation as the CSS strength increased.In most cases,after CSS or MPS,the broken ADS had a relatively more compact structure than before and d（50） is at least 200μm.The CST of the broken fragments from optimally dosed ADS increased,whereas that corresponding to overdosed ADS decreased.MPS treatment resulted in larger and more compact broken ADS fragments with a lower CST value than CSS.During the subsequent slow mixing,the broken ADS aggregates did not recover their charge,size,and dewaterability to the initial values before breakage.In addition,less than 15%self-regrowth in terms of percentage of the regrowth factor was observed in broken ADS after CSS at average velocity gradient no less than 1905.6 sec^（-1）.

关键词： Anaerobic digested sludge Shear Reversibility Structure Dewaterability Floc strength

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17α-Ethynylestradiol biodegradation in different river-based groundwater recharge modes with reclaimed water and degradation-associated community structure of bacteria and archaea

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Journal of Environmental Sciences 2018年第2期30卷 51-61页

作者： Weifang Ma Jiaji Sun Yangyao Li Xiaoxiu Lun Dan Shan Chao Nie Miaomiao Liu College of Environmental Science and Engineering Beijing Forestry University Beijing 100083 China Friendship Center for Environmental Protection Beijing 100029 China Department of Civil and Environmental Engineering university of Illinois at Urbana-Champaign Urbana IL 61801-2352 USA

This study investigated 17α-ethynylestradiol（EE2） biodegradation process and primary metabolic pathways associated with community structures of microorganism during groundwater recharge using reclaimed water. The attenuation rate is 1.58 times higher in wetting and drying alternative recharge（WDAR） than in continual recharge（CR）. The primary biotransformation pathways of EE2 in WDAR system began with the oxidation of C-17 on ring D to form a ketone group, and D-ring was subsequently hydroxylated and cleaved. In the CR system, the metabolic pathway changed from the oxidation of C-17 on ring D to hydroxylation of C-4 on ring A, and ring A or B subsequently cleaved; this transition was related to DO, and the microbial community structure. Four hundred fifty four pyrosequencing of 16 s r RNA genes indicated that the bacterial communities in the upper layer of the WDAR system were more diverse than those found in the bottom layer of the CR system; this result was reversed for archaea. Unweighted Uni Frac and taxonomic analyses were conducted to relate the change in bacterial community structure to the metabolic pathway. Microorganism community diversity and structure were related to the concentrations of dissolved oxygen, EE2 and its intermediates in the system. Five known bacterial classes and one known archaeal class, five major bacterial genera and one major archaeal genus might be involved in EE2 degradation. The findings of this study provide an understanding of EE2 biodegradation in groundwater recharge areas under different recharging modes and can facilitate the prediction of the fate of EE2 in underground aquifers.

关键词： EE2 Biodegradation Groundwater recharge Microbial community and diversity Metabolic intermediates

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Adsorption and biodegradation of three selected endocrine disrupting chemicals in river-based artificial groundwater recharge with reclaimed municipal wastewater

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Journal of Environmental Sciences 2015年第5期27卷 154-163页

作者： Weifang Ma Chao Nie Bin Chen Xiang Cheng Xiaoxiu Lun Fangang Zeng College of Environmental Science and Engineering Beijing Forestry University School of Environment and Natural Resource Renmin University of China

Endocrine disrupting chemical（EDC） pollution in river-based artificial groundwater recharge using reclaimed municipal wastewater poses a potential threat to groundwater-based drinking water supplies in Beijing, China. Lab-scale leaching column experiments simulating recharge were conducted to study the adsorption, biodegradation, and transport characteristics of three selected EDCs： 17β-estradiol（E2）, 17α-ethinylestradiol（EE2） and bisphenol A（BPA）. The three recharge columns were operated under the conditions of continual sterilization recharge（CSR）, continual recharge（CR）, and wetting and drying alternative recharge（WDAR）. The results showed that the attenuation effect of the EDCs was in the order of WDAR 〉 CR 〉 CSR system and E2 〉 EE2 〉 BPA, which followed first-order kinetics. The EDC attenuation rate constants were 0.0783, 0.0505, and 0.0479 m-1 for E2, EE2 and BPA in the CR system, respectively. The removal rates of E2, EE2, and BPA in the CR system were 98%, 96% and 92%, which mainly depended on biodegradation and were affected by water temperature.In the CR system, the concentrations of BPA, EE2, and E2 in soil were 4, 6 and 10 times higher than in the WDAR system, respectively. According to the DGGE fingerprints, the bacterial community in the bottom layer was more diverse than in the upper layer, which was related to the EDC concentrations in the water-soil system. The dominant group was found to be proteobacteria, including Betaproteobacteria and Alphaproteobacteria, suggesting that these microbes might play an important role in EDC degradation.

关键词： Endocrine disrupting chemicals Adsorption Biodegradation Artificial groundwater recharge Bacterial community

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Estimation of PM_(10) in the trafc-related atmosphere for three road types in Beijing and Guangzhou, China

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Journal of Environmental Sciences 2014年第1期26卷 197-204页

作者： Yu Wang Jiong Li Xiang Cheng Xiaoxiu Lun Dezhi Sun Xingzu Wang College of Environmental Science and Engineering Beijing Forestry University Beijing Northland Construction Engineering Co. Ltd

The levels of roadside PM10 in Beijing, China, were investigated in 2011 and 2012 on a seasonal basis to estimate the population exposure to particulates for three road types. The measurements of PM10 were also conducted in the southern Chinese megacity of Guangzhou for comparison purposes. The results showed that roadside PMlo in Beijing correlated strongly with the PM10 background in the urban atmosphere. The levels of PM10 in street canyons were markedly higher than those along the open roads and in crossroad areas because of limited ventilation. An elevation of PM10 was observed in April, which was possibly due to the sand storms that frequently occur in the spring. Based on these observations, roadside PM10 in Beijing could have multiple origins and was to some extent dispersion- governed. In Guangzhou, the roadside PM10 did not closely relate to the background values. The PM10 pollution was greatly affected by local traffic conditions. The simulation of PM10 for different road types was completed during the study period using the Motor Vehicle Emissions Factor Model （MOBILE6.2） as an emission model and the California Line Source Dispersion Model （CALINE4） and Operational Street Pollution Model （OSPM） as dispersion models. The MOBILE6.2/CALINE4 software package was demonstrated to be sufficient for the simulation of PM10 in the open roads and crossroad areas in both Beijing and Guangzhou, and the simulation results of roadside PM10 in the street canyons by the MOBILE6.2/OSPM package were in close agreement with those of the measurements.

关键词： roadside PM10 traffic volume open road crossroad street canyon

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Characteristics and chemical reactivity of biogenic volatile organic compounds from dominant forest species in the Jing-Jin-Ji area,China

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Forest Ecosystems 2021年第4期8卷 699-712页

作者： Ying Lin Xiaoxiu Lun Wei Tang Zhongzhi Zhang Xiaoxi Jing Chong Fan Qiang Wang College of Environmental Science and Engineering Beijing Forestry University100083 BeijingChina Institute of Atmospheric Environment Chinese Research Academy of Environmental Sciences100012 BeijingChina

Background:Biogenic volatile organic compounds(BVOCs)play an essential role in tropospheric atmospheric chemical reactions.There are few studies conducted on BVOCs emission of dominant forest species in the Jing-Jin-Ji area of China.Based on the field survey,forest resources data and the measured standard emission factors,the Guenther model developed in 1993(G93)was applied in this paper to estimate the emission of BVOCs from several dominant forest species(Platycladus orientalis,Quercus variabilis,Betula platyphylla,Populus tomentosa,Pinus tabuliformis,Robinia pseudoacacia,Ulmus pumila,Salix babylonica and Larix gmelinii)in the Jing-Jin-Ji area in 2017.Then the spatiotemporal emission characteristics and atmospheric chemical reactivity of these species were extensively evaluated.Results:The results showed that the total annual BVOCs emission was estimated to be 70.8 Gg C·year^(−1),consisting 40.5%(28.7 Gg C·year^(−1))of isoprene,36.0%(25.5 Gg C·year^(−1))of monoterpenes and 23.4%(16.6 Gg C·year^(−1))of other VOCs.The emissions from Platycladus orientalis,Quercus variabilis,Populus tomentosa and Pinus tabulaeformis contributed 56.1%,41.2%,36.0% and 31.1%,respectively.The total BVOCs emission from the Jing-Jin-Ji area accounted for 61.9% and 1.8%in summer and winter,respectively.Up to 28.8% of emission was detected from Chengde followed by Beijing with 24.9%,that mainly distributed in the Taihang Mountains and the Yanshan Mountains.Additionally,the Robinia pseudoacacia,Populus tomentosa,Quercus variabilis,and Pinus tabulaeformis contributed mainly to BVOCs reaction activity.Conclusions:The BVOCs emission peaked in summer(June,July,and August)and bottomed out in winter(December,January,and February).Chengde contributed the most,followed by Beijing.Platycladus orientalis,Quercus variabilis,Populus tomentosa,Pinus tabulaeformis and Robinia pseudoacacia represent the primary contributors to BVOCs emission and atmospheric reactivity,hence the planting of these species should be reduced.

关键词： Biogenic volatile organic compounds(BVOCs) Isoprene Monoterpenes Jing-Jin-Ji area Spatiotemporal characteristics Chemical reactivity

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Characteristics and influence factors of NO2 exchange flux between the atmosphere and P. nigra

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Journal of Environmental Sciences 2019年第10期31卷 155-165页

作者： Chun Chen Yuzheng Wang Yuanyuan Zhang Chengtang Liu Xiaoxiu Lun Yujing Mu Chenglong Zhang Junfeng Liu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China University of Chinese Academy of Sciences Beijing 100049 China Center for Excellence in Urban Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Xiamen 361021China College of Environmental Science & Engineering Beijing Forest University Beijing 100083 China

Nitrogen dioxide(NO2)is an important substance in atmospheric photochemical processes and can also be absorbed by plants.N02 fluxes between the atmosphere and P.nigrc seedlings were investigated by a double dynamic chambers method in Beijing from June 15to September 3,2017.The range of N02 exchange fluxes between P.nigra seedlings and the atmosphere was from-14.6 to 0.8 nmol/(m2.sec)(the positive data represent N02 emissior from trees,while the negative values indicate absorption).Under ambient concentrations the mean NO2 flux during the fast-growing stage(Jun.15-Aug.4)was-3.0 nmol/(m2·sec)greater than the flux of-1.5 nmol/(m2-sec)during the later growth stage(Aug.8-Sept.3)The daily exchange fluxes of NO2 obviously fluctuated.The fluxes were largest in the morning and decreased gradually over time.Additionally,the N02 fluxes were larger undei high light intensities than under low light intensities during the whole growth period.The effects of temperature on N02 fluxes were different under two growth periods.The NO2exchange fluxes were larger in a range of temperatures close to 44℃in the fast-growing stage,whereas there were no evident differences in N02 exchange fluxes under widel differing temperatures in the later growth stage.Under polluted conditions,the uptake ability of N02 was weakened.Additionally,the compensation point of N02 was 5.6 ppb ir the fast-growing stage,whereas it was 1.4 ppb in the later growth stage.The depositior velocities of NO2 were between 0.3 and 2.4 mm/sec.

关键词： Nitrogen dioxide Exchange flux P.nigra Compensation point

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Long-range transport of organic aerosol to Cape Hedo,Japan

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Particuology 2014年第2期12卷 35-41页

作者： Xiaoxiu Lun Akinori Takami Weifang Ma Akio Shimono Shiro Hatakeyama Beijing Forestry University National Institute for Environmental Studies Onogawa 16-2Tsukuba 305-8506Japan Sanyu Plant Service Co. Ltd.Hashimotodai 1-8-21Kanagawa 229-1132Japan Tokyo University of Agriculture and Technology 3-8-IHarumi-choFuchu-shiTokyo 183-8538Japan

An investigation at Cape Hedo, Japan, from 2005 to 2006, focused on the long-range transport of organic aerosol （OA） from the Asian continent. An Aerodyne aerosol mass spectrometer was used to investigate the OA data collected over the study. OA concentrations were low from July to September and peaked during March and April. Based on air mass origins, four OA source regions were identified： northern China, southern China, Japan, and Korea. OA concentrations measured at Cape Hedo from the four sources did not exhibit large differences. Conversely, the frequencies of the air masses reaching Cape Hedo from the different regions varied considerably. Northern China was identified as the primary source of organic aerosols at Cape Hedo. Examination of variations in the ratio of m/z 44 to OA concentrations with transport time showed that OAs were partially oxidized during transport

关键词： Long-range transportOrganic aerosolSource contributionOkinawa

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