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Characteristics and Influencing Factors of the Microbial Concentration and Activity in Atmospheric Aerosols over the South China Sea

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Journal of Ocean University of China 2021年第2期20卷 257-270页

作者： QI Jianhua YIN Yidan XIE Jiamin LI Mengzhe DING Xue LI Hongtao key laboratory of marine environment and ecology Ministry of EducationOcean University of ChinaQingdao 266100China laboratory for marine ecology and environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China

Oceans are important sources of microbes in atmospheric aerosols;however, information about the characteristics of airborne microbes and their influencing factors over oceans is lacking. Here we report the characteristics of the microbial abundance and activity in aerosols sampled near the sea surface over the South China Sea(SCS) from May to June 2016. The airborne microbial concentration range in the aerosols was 1.68?105 to 4.84?105 cells m-3 over the SCS, reflecting an average decrease of 40% – 54% over the SCS compared with that in the samples from the coastal region of Qingdao. About 63% – 76% of the airborne microbes occurred in coarse particles(> 2.1 ?m), with a variable size distribution over the SCS. The microbial activity range in aerosols, measured by the fluorescein diacetate(FDA) hydrolysis method, was 2.09 – 11.97 ng m-3 h-1 sodium fluorescein(SF) over the SCS, which was 15% – 79% lower than that over the coastal region. These values reflected a different spatial distribution over the SCS from that of the microbial concentration. Except for certain samples, all samples had 68% of the microbial activity occurring in coarse particles. Correlation analysis showed that the microbial abundance and activity were positively correlated with the aerosol, organic carbon(OC), and water-soluble organic carbon(WSOC) concentrations, indicating that the airborne microbes may be related to the reactions of certain water-soluble organic chemicals in the atmosphere. Moreover, the concentrations of airborne microbes were significantly negatively correlated with the horizontal offshore distance. The microbial concentration and activity were significantly correlated with wind speed.

关键词： microbes aerosols microbial activity size distribution WSOC

Response of Microbial Community to Petroleum Stress and Phosphate Dosage in Sediments of Jiaozhou Bay, China

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Journal of Ocean University of China 2014年第2期13卷 249-256页

作者： ZHAO Yangguo CHEN Min BAI Jie LI Xinwei Farhana Zulfiqar WANG Qianli College of environmental Science and Engineering Ocean University of China key laboratory of marine environment and ecology Ministry of Education

The dynamic microcosms were used to evaluate the effect of oil spills on microbial ecological system in marine sediment and the enhancement of nutrient on the oil removal. The function and structure of microbial community caused by the oil pollution and phosphate dosage were simultaneously monitored by dehydrogenase activity assay and PCR-denaturing gradient gel electrophoresis(DGGE) techniques. The results indicated that the amount of total bacteria in all dynamic microcosms declined rapidly with incubation time. The number of petroleum-degrading bacteria and the activity of sediment dehydrogenase were gradually enhanced by petroleum in the oil-treated microcosms, while they both showed no obvious response to phosphate dosage. In comparison, phosphate spiked heterotrophic bacteria and they showed a significant increase in amount. DGGE profiles indicated that petroleum dosage greatly changed community structure, and the bacteria belonged to class Deltaproteobacteria, and phyla Bacteroidetes and Chlorobi were enriched. This study demonstrated that petroleum input greatly impacted the microbial community structure and consequently the marine sediment petroleum-degrading activity was enhanced. Phosphate dosage would multiply heterotrophic bacteria but not significantly enhance the petroleum degradation.

关键词： marine sediments oil spills dehydrogenase activity phosphate heterotrophic bacteria bacterial community

A Comparative Study of CART and PTM for Modelling Water Age

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Journal of Ocean University of China 2015年第1期14卷 47-58页

作者： WANG Haiyan GUO Xinyu LIU Zhe GAO Huiwang key laboratory of marine environment and ecology Ministry of Education Ocean University of China Center for marine environmental Studies Ehime University

CART(Constituent-oriented age and residence time theory) and PTM(Particle-tracking method) are two widely used numerical methods to calculate water age. These two methods are essentially equivalent in theory but their results may be different in practice. The difference of the two methods was evaluated by applying them to calculate water age in an idealized one-dimensional domain. The model results by the two methods are consistent with each other in the case with either spatially uniform flow field or spatially uniform diffusion coefficient. If we allow the spatial variation in horizontal diffusion, a term called pseudo displacement arising from the spatial variation of diffusion coefficient likely plays an important role for the PTM to obtain accurate water age. In particular, if the water particle is released at a place where the diffusion is not the weakest, the water age calculated by the PTM without pseudo displacement is much larger than that by the CART. This suggests that the pseudo displacement cannot be neglected in the PTM to calculate water age in a realistic ocean. As an example, we present its potential importance in the Bohai Sea where the diffusion coefficient varies spatially and greatly.

关键词： CART PTM pseudo displacement water age

Characterization of Bioaerosol Bacterial Communities During Hazy and Foggy Weather in Qingdao, China

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Journal of Ocean University of China 2018年第3期17卷 516-526页

作者： QI Jianhua LI Mengzhe ZHEN Yu WU Lijing key laboratory of marine environmental Science and ecology Ministry of Education Ocean University of China

This study was conducted to evaluate the impact of hazy and foggy weather on the bacterial communities in bioaerosols, for which samples were collected from the Qingdao coastal region on sunny, foggy, and hazy days in January and March 2013. Bacterial community compositions were determined using polymerase chain reaction denaturing gradient gel electrophoresis(PCR-DGGE). The bacterial community diversity was found to be high on foggy and hazy days, and the dominant species differed during hazy weather. The Shannon-Wiener index revealed that the bacterial community diversity of coarse particles was higher than that of fine particles in the bioaerosols. The bacterial community diversity of fine particles significantly correlated with relative humidity(RH; r^2 = 0.986). The cluster analysis results indicated that the bacterial communities on sunny days differed from those on hazy and foggy days. Compared with sunny days, the bacterial communities in the fine particles during hazy weather exhibited greater changes than those in the coarse particles. Most of the sequenced bacteria were found to be closely affiliated with uncultured bacteria. During hazy weather, members of the classes Bacilli and Gammaproteobacteria(Pseudomonas and Acinetobacter) were dominant. The DGGE analysis revealed that Proteobacteria and Firmicutes were the predominant phyla, and their relative percentages to all the measured species changed significantly on hazy days, particularly in the fine particles. Haze and fog had a significant impact on the bacterial communities in bioaerosols, and the bacterial community diversity varied on different hazy days.

关键词： bacterial community bioaerosols haze fog Qingdao

Process analysis of PM_(2.5) pollution events in a coastal city of China using CMAQ

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Journal of environmental Sciences 2019年第5期31卷 225-238页

作者： Qiang Zhang Di Xue Xiaohuan Liu Xiang Gong Huiwang Gao College of environmental Science and Engineering Ocean University of China key laboratory of marine environment and ecology Ministry of Education Ocean University of China laboratory for marine ecology and environmental Sciences Qingdao National Laboratory for Marine Science and Technology Qingdao University of Science and Technology

US EPA's Community Multiscale Air Quality modeling system(CMAQ) with Process Analysis tool was used to simulate and quantify the contribution of individual atmospheric processes to PM_(2.5) concentration in Qingdao during three representative PM_(2.5) pollution events in the winter of 2015 and 2016. Compared with the observed surface PM_(2.5) concentrations, CMAQ could reasonably reproduce the temporal and spatial variations of PM_(2.5) during these three events. Process analysis results show that primary emissions accounted for 72.7%–93.2% of the accumulation of surface PM_(2.5) before and after the *** the events occurred, primary emissions were still the major contributor to the increase of PM_(2.5) in Qingdao, however the contribution percentage reduced significantly,which only account for 51.4%–71.8%. Net contribution from horizontal and vertical transport to the accumulation of PM_(2.5) was also positive and its percentage increased when events occurred. Only 1.1%–4.6% of aerosol accumulation was due to PM processes and aqueous chemical processes before and after events. When the events occurred,contribution from PM processes and aqueous chemistry increased to 6.0%–11.8%. Loss of PM_(2.5) was mainly through horizontal transport, vertical transport and dry deposition, no matter during or outside the events. Wet deposition would become the main removal pathway of PM_(2.5), when precipitation occurred.

关键词： CMAQ Process analysis PM2.5 Qingdao

Wave-induced seepage and its possible contribution to the formation of pockmarks in the Huanghe(Yellow) River delta

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Chinese Journal of Oceanology and Limnology 2016年第1期34卷 200-211页

作者：王虎刘红军张民生王秀海 key laboratory of marine environment and ecology Ministry of EducationOcean University of China College of environmental Science and Engineering Ocean University of China

Wave-induced seepage and its possible contribution to the formation of pockmarks in the Huanghe(Yellow) River delta were investigated experimentally and numerically. laboratory experiments were carried out to explore the response of a layered silty seabed with various saturation conditions under cyclic wave loads,in which the pore pressure and seepage-related phenomena were particularly monitored. Numerical models to simulate wave-induced seepage in the seabed were presented and evaluated,then applied to the Huanghe River delta. The experimental results show that the excess pore pressure decreases more rapidly at the surface layer,while the seepage-related phenomena are more pronounced when large cyclic loads are applied and the underlying layer is less saturated. The proposed numerical models were verified by comparing with the experiments. The calculated seepage depth agreed well with the depth of the pockmarks in the Huanghe River delta. The experimental and numerical results and the existing insitu investigations indicate that the wave-induced seepage may be a direct cause of the pockmarks in the Huanghe River delta. Extreme storm waves and the dual-layered structure of hard surface layer and weak underlying layer are essential external and internal factors,respectively. Wave- or current-induced scour and transport are possible contributors to the reformation of pockmarks at a later stage.

关键词： wave loads seepage excess pore pressure pockmarks Huanghe (Yellow) River delta

Molecular phylogeography and population genetic structure of the planktonic copepod Calanus sinicus Brodsky in the coastal waters of China

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Acta Oceanologica Sinica 2014年第10期33卷 74-84页

作者： HUANG Yousong LIU Guangxing CHEN Xiaofeng College of environmental Science and Engineering Ocean University of China key laboratory of marine environment and ecology of ministry of education Ocean University of China

Planktonic copepod Calanus sinicus is the dominant meso-zooplankton in the Northwest Pacific Ocean. To better understand its population dynamics and phylogeographic patterns, 243 C. sinicus individuals were collected from seven locations across the shelf waters of China and its population genetics was studied by mitochondrial DNA cytochrome oxidase I（mtCOI） sequences analyses. Thirty-nine different sequences, or haplotypes, were detected with moderate haplotype diversity（h=0.749） and low nucleotide diversity（π=0.003） for all populations. The evolutionary divergence between geographic populations varied from 0.24% to 0.37%, indicative of very limited genetic differentiation. Visualized minimum spanning network（MSN） and phylogenetic analysis of all the detected haplotypes did not reveal any clear phylogeographic pattern. Furthermore, AMOVA data showed no significant spatial population differentiation existed among the individuals collected across China shelf waters. Pairwise FST values showed that population collected from northwest of the East China Sea（ECS） displayed a low difference to other populations. Mismatch distribution analyses and neutrality tests indicated that C. sinicus might undergo a demographic/population expansion. No significant population genetic structuring was detected, indicating an extensive gene flow among the C. sinicus populations. Our results provide molecular evidence for the hypothesis that C. sinicus in the northwestern South China Sea in winter is transported from the East China Sea and the Yellow Sea by the China Coastal Current during the northeast monsoon period.

关键词： copepod Calanus sinicus mtCOI population genetic differentiation China Coastal Current

Long-term impacts of graphene oxide and Ag nanoparticles on anammox process: Performance, microbial community and toxic mechanism

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Journal of environmental Sciences 2019年第5期31卷 239-247页

作者： Huai Li Zifang Chi Baixing Yan key laboratory of Wetland ecology and environment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences key laboratory of Groundwater Resources and environment Ministry of Education Jilin University

The increasing application of engineered nanoparticles(NPs) has posed an emerging challenge to constructed wetland wastewater treatment. The performance, microbial community and toxic mechanism of anammox-based unplanted subsurface-flow constructed wetlands(USFCWs) were investigated under the long-term exposure of different graphene oxides(GOs) and Ag NP concentrations. Results showed that the addition of GO could promote TN removal, manifesting as function anammox bacteria C. Anammoxoglobus having a relative high abundance, for GO did not cause significant damage to the cell integrity though there was an increase in ROS concentrations. TN removal would not be obviously affected under exposure of 1 mg/L Ag NPs, for the function gene related to cell biogenesis and repair was up-regulated; while the addition of 10 mg/L Ag NPs would have an inhibiting effect on TN removal in the USFCWs, for the disappearance of some species having anammox ability. key enzymes of anammox process(NIR and HDH) decreased to some extent under GO and Ag NP exposure, and function gene of defense mechanisms had an increase trend in samples.

关键词： Anammox Ag NPs GO Microbial community Function gene key enzymes

The Effects of Reclamation Activity and Yellow River Runoff on Coastline and Area of the Laizhou Bay,China

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Journal of Ocean University of China 2021年第3期20卷 729-739页

作者： XU Yandong GAO Huiwang WEI Xiao ZHU Jinlong key laboratory of marine environment and ecology Ministry of EducationOcean University of ChinaQingdao 266100China Shandong Provincial key laboratory of Restoration for marine ecology Shandong Marine Resource and Environment Research InstituteYantai 264006China laboratory for marine ecology and environmental Science Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China

Study on morphological changes of a bay can help to identify the effects of anthropogenic activities on coastal environ-ment and guide the exploration of marine *** this paper,morphological data including coastline and water areas in five discrete years between 1968 and 2015 were selected and extracted from the remote sensing images and historical marine charts to study the morphological changes in Laizhou Bay(LZB),one of the bays in the southwest of the Bohai Sea.A systematic analysis on spatial variations of the coastline and the surface areas of different types of waters in LZB was *** results showed that the surface area of LZB was decreased by 1253.2km^(2)in the last half century,which is 17.4%of the total in the *** areas of the natural wetland and the intertidal zone were decreased by 17.2%and 56.1%,respectively,and the average water depth varied from 9.05 m to 8.16m at low tide level from 1968 to *** coastline and shape variations of the bay turned to be complex after the 1980s,and the shape index of LZB showed an increasing trend in more recent *** centroid of the bay generally migrated to the northeast direction,i.e.,the direction of the center of the Bohai Sea,and the shrinking direction of the bay was consistent with the migration direction of the *** reclamation area during 1968-2015 in LZB was 1201.7km^(2),and 94.1%was in the inter-tidal *** overall morphological change of the bay during the last half century was mainly controlled by the coastal reclamation activities,and the Yellow River runoff including the river course change and sediment load variation was also an important control-ling factor.

关键词： morphological change coastal reclamation Yellow River runoff Laizhou Bay