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Fast spreading of surface ozone in both temporal and spatial scale in pearl river delta

Journal of Environmental Sciences 2024年第3期137卷 540-552页

作者： Tianhui Cao Haichao Wang Lei Li Xiao Lu Yiming Liu Shaojia Fan School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Provincial Observation and Research Station for Climate Environment and Air Quality Change in the pearl river Estuary Key Laboratory of Tropical Atmosphere-Ocean SystemMinistry of EducationZhuhai 519082China

Surface ozone(O_(3))is a major air pollutant and draw increasing attention in the pearl river delta(PRD),China.Here,we characterize the spatial-temporal variability of ozone based on a dataset obtained from 57 national monitoring sites during 2013-2019.Our results show that:(1)the seasonal difference of ozone distribution in the inland and coastal areas was significant,which was largely affected by the wind pattern reversals related to the East Asian monsoon,and local ozone production and destruction;(2)the daily maximum 8hr average(MDA8 O_(3))showed an overall upward trend by 1.11 ppbv/year.While the trends in the nine cities varied differently by ranging from-0.12 to 2.51 ppbv/year.The hot spots of ozone were spreading to southwestern areas from the central areas since 2016.And ozone is becoming a year-round air pollution problem with the pollution season extending to winter and spring in PRD region.(3)at the central and southwestern PRD cities,the percentage of exceedance days from the continuous type(defined as≥3 days)was increasing.Furthermore,the ozone concentration of continuous type was much higher than that of scattered exceedance type(<3 days).In addition,although the occurrence of continuous type starts to decline since2017,the total number of exceedance days during the continuous type is increasing.These results indicate that it is more difficult to eliminate the continuous exceedance than the scatter pollution days and highlight the great challenge in mitigation of O_(3)pollution in these cities.

关键词： Surface ozone pollution Ozone trend Spatial and temporal variability pearl river delta Pollution mitigation

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Distribution characteristics of photoinitiators and their flux estimation from the pearl river delta to the coastal waters of the South China Sea

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Journal of Environmental Sciences 2023年第6期128卷 71-80页

作者： Yuqing He Zibin Pan Xinxin Liang Ruiman Xie Yuying Sun Juan Li YaweiWang Lixi Zeng Guangdong Key Laboratory of Environmental Pollution and Health School of EnvironmentJinan UniversityGuangzhou 511443China Guangdong-Hongkong-Macao Joint Laboratory of Collaborative Innovation for Environmental Quality Jinan UniversityGuangzhou 511443China Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China

Photoinitiators(PIs)are widely used in industrial polymerization processes.It has been reported that PIs are ubiquitous in indoor environments and that humans are exposed to PIs,but the occurrence of PIs in natural environments are rarely known.In the present study,25 PIs,including 9 benzophenones(BZPs),8 amine co-initiators(ACIs),4 thioxanthones(TXs)and 4 phosphine oxides(POs),were analyzed in water and sediment samples collected from eight riverine outlets of the pearl river delta(PRD).Eighteen,14,and 14 of the 25 target PIs were detected in water,suspended particulatematter(SPM)and sediment samples,respectively.The total concentrations of PIs in water,SPM,and sediment were in the ranges of 2.88–96.1 ng/L,9.25–923 ng/g dry weight(dw),and 3.79–56.9 ng/g dw,with geometric mean concentration(GM)of 10.8 ng/L,48.6 ng/g dw,and 17.1 ng/g dw,respectively.A significant linear regression was observed between the log partitioning coefficients(Kd)values of PIs and their log octanol water partition coefficient(Kow)values(R^(2)=0.535,priverine input of PIs to the coastal waters of the South China Sea via eightmain outlets of the PRD was estimated to be 4.12×10^(3)kg/year,and the∑BZPs,∑ACIs,∑TXs and∑POs contributed to 1.96×10^(3),1.24×10^(3),89.6 and 830 kg/year,respectively.This is the first report of a systematic description of the occurrence characteristics of PIs exposure in water,SPM,and sediment.The environmental fate and risks of PIs in aquatic environments need further investigations.

关键词： Photoinitiators riverine inputs Distribution characteristics Partitioning coefficients pearl river delta

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The Middle-aged and Knowledge Workers: Demographic and Economic Changes in the pearl river delta, China

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Chinese Geographical Science 2022年第2期32卷 268-284页

作者： FENG Pengfei Anna GROWE SHEN Yuming College of Resources Environment&TourismCapital Normal UniversityBeijing 100048China Institute of Geography Heidelberg UniversityBerliner Strafie 48D-69120 HeidelbergGermany

Demographic and economic development can be seen as two sides of one coin in the process of regional development.This article deals with how economic and demographic changes influence the settlement structure and development of the pearl river delta(PRD)and lead to regionalization processes within the large agglomerations.The aim of the study was to understand the interrelation between the three aspects:economic change,demographic change and change of spatial structures.Based on population age and occupational data,spatial changes in demographic structure and economic activities from 2000 to 2010 were analyzed.It was found that the demographic and economic change reflected changing spatial patterns between the urban centers and the hinterland in the PRD.Two processes were apparent during the studied period in the hinterlands and the high-density areas of the PRD.On one hand,the hinterlands in the PRD attracted more manufacturing activities,while the inner high-density areas experienced a decrease in manufacturing,associated with an increase in young labor in regions where workplaces that only required limited education expanded.On the other hand,specialization in knowledge-intensive business services increased in the inner high-density areas,which also saw an increased share in the older population.This finding suggests that increasing knowledge-intensive work correlates with higher age structures due to the longer formal education required and also the benefits knowledge workers accrue through experience and gained knowledge over time.Therefore,based on a transformation process,we tentatively conclude that the populations in high-density areas in the PRD became more middle-aged and were represented by more knowledge workers.

关键词： manufacturing knowledge-intensive business services(KIBS) economic change demographic change pearl river delta

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Abundance and diversity of ammonia-oxidizing archaea in response to various habitats in pearl river delta of China, a subtropical maritime zone

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Journal of Environmental Sciences 2013年第6期25卷 1195-1205页

作者： Zhixin Li Wenbiao Jin Zhaoyun Liang Yangyang Yue Junhong Lv Shenzhen Key Laboratory of Water Resource Utilization and Environmental Pollution Control Harbin Institute of Technology Shenzhen Graduate School Shenzhen Institute of Advanced Technology Chinese Academy of Sciences

Ammonia-oxidizing archaea （AOA） are widely considered key to ammonia oxidation in various environments. However, little work has been conducted to simultaneously investigate the abundance and diversity of AOA as well as correlations between archaeal amoA genotypes and environmental parameters of different ecosystems at one district. To understand the abundance, diversity, and distribution of AOA in pearl river delta of China in response to various habitats, the archaeal amoA genes in soil, marine, river, lake, hot spring and wastewater treatment plant （WWTP） samples were investigated using real-time fluorescent quantitative PCR and clone libraries. Our analyses indicated that the diversity of AOA in various habitats was different and could be clustered into five major clades, i.e., estuary sediment, marine water/sediment, soil, hot spring and Cluster 1. Phylogenetic analyses revealed that the structure of AOA communities in similar ecological habitats exhibited strong relation. The canonical correspondence method indicated that the AOA community structure was strongly correlated to temperature, pH, total organic carbon, total nitrogen and dissolved oxygen variables. Assessing AOA amoA gene copy numbers, ranging from 6.84× 10^6 to 9.45 × 10^7 copies/g in dry soil/sediment, and 6.06× 10^6 to 2.41 ×10^7 copies/L in water samples, were higher than ammonia-oxidizing bacteria （AOB） by 1-2 orders of magnitude. However, AOA amoA copy numbers were much lower than AOB in WWTP activated sludge samples. Overall, these studies suggested that AOA may be a major contributor to ammonia oxidation in natural habitats but play a minor role in highly aerated activated sludge. The result also showed the ratio of AOA to AOB amoA gene abundance was positively correlated with temperature and less correlated with other environmental parameters. New data from our study provide increasing evidence for the relative abundance and diversity of ammonia-oxidizing archaea in the global nitrogen cycle.

关键词： ammonia-oxidizing archaea abundance community structure real-time quantitative PCR clone library pearl river delta

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Characterizing ionic species in PM_(2.5) and PM_(10) in four pearl river delta cities,South China

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Journal of Environmental Sciences 2007年第8期19卷 939-947页

作者： LAI Sen-chao ZOU Shi-chun CAO Jun-ji LEE Shun-cheng HO Kin-fai School of Chemistry and Chemical Engineering Sun Yat-sen University Guangzhou 510275 China. Department of Civil and Structural Engineering The Hong Kong Polytechnic University Hong Kong State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi＇ an 710075 China

PM2.5 and PM10 samples were collected at four major cities in the pearl river delta （PRD）, South China, during winter and summer in 2002. Six water-soluble ions, Na^＋, NH4＋, K^＋, Cl^-, NO3^- and SO4^2- were measured using ion chromatography. On average, ionic species accounted for 53.3% and 40.5% for PM2.5 and PM10, respectively in winter and 39.4% and 35.2%, respectively in summer. Secondary ions such as sulfate, nitrate and ammonium accounted for the major part of the total ionic species. Sulfate was the most abundant species followed by nitrate. Overall, a regional pollution tendency was shown that there were higher concentrations of sulfate, nitrate and ammonium in Guangzhou City than those in the other PRD cities. Significant seasonal variations were also observed with higher levels of species in winter but lower in summer. The Asian monsoon system was favorable for removal and diffusion of air pollutants in PRD in summer while highly loading of local industrial emissions tended to deteriorate the air quality as well. NO3^-/SO4^2- ratio indicated that mobile sources have considerably contribution to the urban aerosol, and stationary sources should not be neglected. Besides the primary emissions, complex atmospheric reactions under favorable weather conditions should be paid more attention for the control of primary emission in the PRD region.

关键词： water-soluble ions seasonal and spatial variations pearl river delta

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Heavy metal concentrations in edible bivalves and gastropods available in major markets of the pearl river delta

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Journal of Environmental Sciences 2001年第2期13卷 210-217页

作者： FANG Zhan-qiang CHEUNG R.Y.H. WONG M.H. Department of Biology South China Normal UniversityGuangzhou 510631China Department of Biology and Chemistry City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong Institute for Natural Resources and Waste Management and Department of BiologyHong Kong Bapt ist UniversityKowloon TongHong Kong

Molluscs are able to accumulate heavy metals and impose health hazard to consumers. The main objective of the present study is to investigate the heavy metal concentrations in edible bivalves and gastropods available in major markets of the pearl river delta. Fourteen species of edible molluscs were purchased from six markets in Hong Kong and Guangdong Province. The fresh of these biota were tested for their cadmium (Cd), copper (Cu), zinc (Zn), lead (Pb), nickel (Ni), chromium (Cr), antimony (Sb) and tin (Sn) concentrations (based on wet weight). The results indicated that amongst the 14 edible molluscs, only Cd, Pb, Ni, Cr, Sb and Sn concentrations in three species (Ruditapes philippinarum, Perna viridis and Hemifusus tuba) were within the local regulatory limits. Over 60% of bivalve species exceeded maximum permitted levels of Cd (2 mug/g) and Cr (1 mug/g), while over 40% of gastropod species exceeded the maximum levels of Sb (1 mug/g) and Cr (1 mug/g). Most of the samples collected from Hong Kong had significantly higher contents of Pb and Sb, but similar levels of Cd, Cu and Zn when compared with samples collected across the border ( p < 0.05; p 0.01; p < 0.001 respectively). In general, the molluscs purchased in Guangdong markets had higher metal contents than those purchased from the Hong Kong markets. When compared with the Provisional Tolerable Weekly Intake or Maximum Acceptable Daily Load recommended by FAO/WHO Expert Committee on Food Additives, Cd levels of five species (Anadara ferruginea, Pinna pectinata, Chlamys nobilis, Babylonia lutosa and Hemifusus terntanus) and Cr levels of seven species ( Anadara ferruginea, Paphia undulata, Pinna pectinata, Babylonia lutosa, Hemifusus terntanus, Cymbium melo and Cipangopaludina chinensis) were higher than both the human daily acceptable limits (for Cd and Cr respectively) and the local regulatory levels (for Cd and Cr respectively).

关键词： heavy metals edible molluscs human health pearl river delta

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Developing chemical signatures of particulate air pollution in the pearl river delta region, China

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Journal of Environmental Sciences 2011年第7期23卷 1143-1149页

作者： Mei Zheng Yuan Cheng Limin Zeng Yuanhang Zhang College of Environmental Sciences and Engineering Peking University Beijing 100871 China School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta GA 30332 USA

PM 2.5 samples were collected in a regional sampling network with three sites in Hong Kong and four sites in the adjacent inland pearl river delta （PRD） or Guangdong Province during four months/seasons from 2002–2003. Trans-boundary transport between Hong Kong and the inland PRD is inevitable under the influence of Asian monsoon. In summer, Hong Kong serves as the upwind site of the inland PRD while during other seasons it is under the influence of continental emissions. Previous studies have recognized the importance of using chemical signatures to differentiate local vs. regional contributions to air pollutants in Hong Kong such as the CO/NOx ratio, ratios of different VOC species. In this study, detailed chemical speciation by gas chromatography-mass spectrometry was performed with PM 2.5 samples to identify new chemical signatures to distinguish aerosols in Hong Kong from those from the inland PRD. Since Hong Kong is not influenced by the continental emissions from the inland PRD during summer, comparison focused on chemical data obtained from this season for chemical signatures. The new ratios developed from the current study include LCPI/HCPI ratio of alkanes （0.39 ± 0.02 in Hong Kong vs. 0.78 ± 0.08 in the inland PRD）, pyrene to benzo[ghi]perylene ratio （0.97 ± 0.21 in Hong Kong compared to 0.20 ± 0.06 in the inland PRD）, and the ratio of 1,2-benzenedioic acid to 1,4-benzenedioic acid （1.8 ± 0.1 in Hong Kong vs. 0.6 ± 0.05 in the inland PRD）. Results from this study also revealed that Hong Kong was impacted by ship emissions as reflected by substantially high V/Ni ratio （9 ± 2） while this ratio was about 1–2 at all sites in the inland PRD, which is very close to typical ratios from residual oil combustion.

关键词： PM 2.5 chemical signature local and regional air pollution Hong Kong pearl river delta

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Assessment of major ions and heavy metals in groundwater： a case study from Guangzhou and Zhuhai of the pearl river delta, China

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Frontiers of Earth Science 2016年第2期10卷 340-351页

作者： Yintao LU Changyuan TANG Jianyao CHEN Hong YAO School of Civil Engineering Beijing Jiaotong University Beijing 100044 China Faculty of Horticulture Chiba University Chiba 271-8510 Japan School of Geography and planning Sun Yat-sen University Guangzhou 510275 China

Anthropogenic activities in the pearl river delta （PRD） have caused a deterioration of groundwater quality over the past twenty years as a result of rapid urbanization and industrial development. In this study, the hydrochemical characteristics, quality, and sources of heavy metals in the groundwater of the PRD were investigated. Twenty-five groundwater samples were collected and analyzed for pH, electrical conductivity （EC）, total dissolved solids （TDS）, δ18O,δ~2H, major ions, and heavy metals. The groundwater was slightly acidic and presented TDS values that ranged from 35.5 to 8,779.3 mg.L-1. The concentrations of the major ions followed the order Cl- 〉 HCO3-〉 Na＋〉 SO24- 〉 NO3 〉 NH4＋〉 Ca2＋〉 K＋〉 Mg2＋〉 Fe2＋/3＋〉 Al3＋. Ca-Mg- HCO3 and Na-K-HCO3 were the predominant types of facies, and the chemical composition of the groundwater was primarily controlled by chemical weathering of the basement rocks, by mixing of freshwater and seawater and by anthropogenic activities. The heavy metal pollution index （HPI） indicated that 64% of the samples were in the low category, 16% were in the medium category and 20% were in the high category, providing further evidence that this groundwater is unsuitable for drinking. Lead, arsenic, and manganese were mainly sourced from landfill leachate; cadmium from landfill leachate and agricultural wastes; mercury from the discharge of leaehate associated with mining activities and agricultural wastes; and chromium primarily from industrial wastes. According to the irrigation water quality indicators, the groundwater in the PRD can be used for irrigation in most farmland without strong negative impacts. However, approximately9 million people in the Guangdong Province are at risk due to the consumption of untreated water. Therefore, we suggest that treating the groundwater to achieve safer levels is necessary.

关键词： pearl river delta groundwater quality,hydrochemical type sodium salts accumulation heavymetal pollution

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The Coupling Effect of Flood Discharge and Storm Surge on Extreme Flood Stages: A Case Study in the pearl river delta, South China

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International Journal of Disaster Risk Science 2021年第4期12卷 495-509页

作者： Xianwei Wang Yu Guo Jie Ren School of Geography and Planning Sun Yat-sen UniversityGuangzhou510275China Guangdong Provincial Engineering Research Center for Public Security and Disasters Guangzhou510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China School of Marine Science Sun Yat-sen UniversityZhuhai519080China

The low-lying pearl river delta in South China is subject to severe flood threats due to watershed floods,sea level rise,and storm surges.It is still unknown to what extent and how far inland storm surges and sea level rise impact the extreme flood stages.This study investigated the coupling effect of flood discharge and storm surge on the extreme flood stages in the pearl river delta by using on site observations and simulations generated by the Hydrologic Engineering Center-river Analysis System model.The results show that flood discharges dominated the flood stages in the middle and upper pearl river delta,while the storm surges had maximum impact near the river mouth.The storm surges and flood stages showed a significant increase after 2002 in the Hengmen waterway.The design flood stages for the post-2002 period were 0.23–0.89 m higher than the pre-2002 ones at Hengmen at the six return periods from 5 to 200 years examined in this study.Their difference declined toward the upper waterway and reduced to zero about 23 km away from the Hengmen outlet.The coincidence of extreme flood discharges and storm surges further escalates the extreme flood stages in the lower 30 km of estuarine waterways.Our results quantify the severe threats due to sea level rise and intensified storm surges in the lower pearl river delta,and are significant for urban planning and designing and managing flood control facilities in the pearl river delta and in other coastal fluvial deltas.

关键词： Extreme flood stages Flood pearl river delta Sea level rise Storm surge

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Remote sensing study of wetlands in the pearl river delta during 1995-2015 with the support vector machine method

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Frontiers of Earth Science 2018年第3期12卷 521-531页

作者： Xiaosong HAN Jiayi PAN Adam T. DEVLIN Institute of Space and Earth Information Science The Chinese University of Hong Kong Hong Kong China

In recent years, experienced rapid economic the pearl river delta has growth which may create a substantial burden to its ecology. In this study, the wetlands of the pearl river delta are investigated. Through the use of remote sensing methods, we analyze spatial and temporal variations of wetlands in this area over the past twenty years. The support vector machine （SVM） method is proven to be an effective approach for classifying the wetlands of the pearl river delta, and the total classifica- tion resolution reaches 94.94% with a Kappa coefficient exceeding 0.94, higher than other comparable analysis methods. Our results show that wetland areas were reduced by 36.9% during the past twenty years. The change detection analysis method shows that there was a 95.58% intertidal zone change to other land-use types, most of which （57.12%） was converted to construction land. In addition, farmland was reduced by 54.89% during the past twenty years, 47.19% of which was changed to construction land use. The inland water area increased 19.02%, but most of this growth （18.77%） was converted from the intertidal zone.

关键词： wetland pearl river delta support vector machine method Landsat images

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