Photobacterium pectinilyticum sp. nov., a novel bacterium isolated from surface seawater of Qingdao offshore.

A Gram-staining-negative, facultative aerobic, motile strain, designated strain ZSDE20T, was isolated from the surface seawater of Qingdao offshore. Phylogenetic analysis of the 16S rRNA gene of strain ZSDE20T, affiliated it to the genus Photobacterium. It was closely related to Photobacterium lutimaris DF-42 T (98.92% 16S rRNA gene sequence similarity). Growth occurred at 4-28ºC (optimum 28ºC), pH 1.0-7.0 (optimum 7.0) and in the presence of 1-7% (w/v) NaCl (optimum 3%). The dominant fatty acids were summed feature 3 (C16:1 ω7c or/and C16:1 ω6c, 34.23%), summed feature 8 (C18:1 ω7c and C18:1 ω6c, 10.36%) and C16:0 (20.05%). The polar lipids of strain ZSDE20T comprised phosphatidylethanolamine, phosphatidylcholine, lyso-phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol dimannoside, phosphatidylinositol mannosides and two unknown lipids. The major respiratory quinone was ubiquinone-8 (Q-8). The DNA G + C content of strain ZSDE20T was 45.6 mol%. Average nucleotide identity (ANI) values between ZSDE20T and its reference species were lower than the threshold for species delineation (95-96%); in silico DNA-DNA hybridization further showed that strain ZSDE20T had less than 70% similarity to its relatives. Based on the polyphasic evidences, strain ZSDE20T is proposed as representing a novel species of the genus Photobacterium, for which the name Photobacterium pectinilyticum sp. nov. is proposed. The type strain is ZSDE20T (= MCCC 1K06283T = KCTC 82885 T).

A framework for urban resilience measurement and enhancement strategies: A case study in Qingdao, China.

Comprehensive measurement and analysis of urban resilience is essential to ensure sustainable urban development. This paper creates a multilevel urban resilience evaluation index system based on four dimensions of economy, society, ecology, and infrastructure and the three attributes (resistance, recovery, and adaptability), then applies the framework to Qingdao, China. The results suggest that: (1) The overall level of urban resilience in Qingdao showed an upward trend, rising from a relatively high level in 2012 to a high level in 2021. Economic and social resilience maintained a high consistency, developing rapidly, while the development of ecological and infrastructure resilience fluctuated, and infrastructure resilience was slow and lagging. (2) Qingdao's overall resilience is higher than other cities in the same region, but infrastructure resilience is relatively low. Moreover, the coupling coordination degree (CCD) of the resilience of the four subsystems in Qingdao has evolved from near imbalance to good coordination. (3) Infrastructure resilience is the primary obstacle factor in the dimension layer, followed by ecological resilience. Based on the results, corresponding improvement strategies are proposed. A comprehensive multidimensional measurement of the urban resilience of Qingdao can identify the main shortcomings and provide a reference for decision-making and resource allocation in resilient cities.

Vibrio amylolyticus sp. nov. and Vibrio gelatinilyticus sp. nov., two marine bacteria isolated from surface seawater of Qingdao.

Two Gram-stain-negative, oxidase-positive, facultative anaerobic and rod-shaped motile bacteria, designated strains ZSDZ34 and ZSDE26, were isolated from offshore surface seawater collected near Qingdao. Phylogenetic analysis based on 16S rRNA gene sequences placed ZSDE26T and ZSDZ34T within the genus Vibrio, family Vibrionaceae, class Gammaproteobacteria. Strain ZSDE26T was most closely related to Vibrio gallaecicus VB 8.9T with 97.3 % sequence similarity, whereas ZSDZ34T was most closely related to Vibrio aestuarianus subsp. cardii DSM 109723T with 97.8 % sequence similarity. Strain ZSDE26T grew with 1-5 % (w/v) NaCl (optimum, 4 %), at 16-28 °C (optimum, 28 °C) and at pH 6.0-9.0 (optimum, pH 7.0). Growth of strain ZSDZ34T occurred with 1-6 % (w/v) NaCl (optimum, 3 %), at 16-37 °C (optimum, 28 °C) and at pH 6.0-9.0 (optimum, pH 7.0). Both strains shared the same major fatty acid components (more than 10 % of total fatty acids) of summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and C16 : 0. Additionally, strain ZSDZ34T contained a higher proportion of iso-C16 : 0. The DNA G+C contents of strains ZSDE26T and ZSDZ34T were 42.8 and 44.5 mol%, respectively. On the basis of the results of polyphasic analysis, ZSDE26T and ZSDZ34T are considered to represent novel species within the genus Vibrio, for which the names Vibrio amylolyticus sp. nov. (type strain, ZSDE26T=KCTC 82890T=MCCC 1K06290T) and Vibrio gelatinilyticus sp. nov. (type strain, ZSDZ34T=KCTC 82888T=MCCC 1K06292T) are proposed, respectively.

Photobacterium obscurum sp. nov., a marine bacterium isolated from the coast of Qingdao.

A Gram-stain-negative, facultative anaerobic, rod-shaped strain, named SDRW27T, was isolated from offshore seawater collected near Qingdao. Strain SDRW27T was able to grow at 16-37 °C (optimum, 28 °C), pH 6.0-9.0 (optimum, pH 6.0) and in the presence of 1-7 % (w/v) NaCl (optimum, 3 %). Phylogenetic analysis using 16S rRNA gene sequences indicated that strain SDRW27T was most closely related to Photobacterium toruni H01100410BT (97.89 % sequence similarity), Photobacterium andalusiense H01100409BT (97.89 %) and Photobacterium leiognathi ATCC 25521T (97.82 %). The predominant fatty acids were summed feature 3 (C16 : 1 ω7c and/or iso-C15 : 0 2-OH), summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and C16 : 0. The polar lipids of strain SDRW27T comprised phosphatidylglycerol, phosphatidylinositol dimannoside, phosphatidylcholine, phosphatidylethanolamine and three unidentified lipids. The major respiratory quinone was ubiquinone-8. The G+C content was 47.71 mol%. The genome size was 5.84 Mbp, including 85 contigs with an N50 value of 223 542. The average nucleotide identity (ANI) values of SDRW27T with its three most similar strains, P. toruni H01100410BT, P. andalusiense H01100409BT and P. leiognathi ATCC 25521T, were 71.36, 71.58 and 72.23 %, respectively (all lower than the 95-96 % ANI threshold), and the DNA-DNA hybridization (DDH) values were 20.4, 20.8 and 20.4 % (all lower than the 70 % DDH threshold). The obtained results of polyphasic analysis demonstrate that strain SDRW27T represents a novel species, for which the name Photobacterium obscurum sp. nov. is proposed. The type strain is SDRW27T (=MCCC 1K06286T=KCTC 82892T).

Vibrio paucivorans sp. nov. and Vibrio qingdaonensis sp. nov., two marine bacteria.

Two Gram-stain-negative, facultatively anaerobic, motile, rod-shaped and flagellated marine bacteria, designated strains DBSS07T and ZSDZ65T, were isolated from the surface sediments of the Bohai sea and Qingdao coastal seawater, respectively. Phylogenetic analysis based on 16S rRNA genes, multilocus sequence analysis (MLSA), phylogenomic analysis of single-copy gene families and whole-genome data placed DBSS07T and ZSDZ65T within the genus Vibrio. DBSS07T was most closely related to Vibrio aestivus M22T, with 97.51 % sequence similarity, whereas ZSDZ65T was most closely related to Vibrio variabilis R-40492T with 97.58 % sequence similarity. DBSS07T grew with 1-7 % (w/v) NaCl (optimum 3 %), at 16-37 °C (optimum 28 °C) and at pH 6.0-9.0 (optimum pH 7.0); whereas ZSDZ65T grew with 1-5 % (w/v) NaCl (optimum 2 %), at 16-32 °C (optimum 28 °C) and at pH 6.0-9.0 (optimum pH 8.0). Both strains shared the same major fatty acid components (more than 10 % of total fatty acids) of summed feature 3 (C16 : 1ω7c or/and C16 : 1ω6c), with different proportions. The DNA G+C contents of DBSS07T and ZSDZ65T were 44.7 and 44.3 %, respectively. On the basis of the results of polyphasic analysis, DBSS07T and ZSDZ65T are considered to represent novel species within the genus Vibrio, for which the names V. paucivorans sp. nov. (type strain, DBSS07T = KCTC 82896T= MCCC 1K06284T) and V. qingdaonensis sp. nov. (type strain, ZSDZ65T = KCTC 82893T = MCCC 1K06289T) are proposed, respectively.

Phylogenetic analyses of 41 Y-STRs and machine learning-based haplogroup prediction in the Qingdao Han population from Shandong province, Eastern China.

BACKGROUND: Known for its rich history and culture, Qingdao is a typical symbol of Chinese maritime culture. Its unique genetic landscape has aroused interest among geneticists and forensic scientists. However, the genetic landscape of Qingdao has never been uncovered. AIM: This investigation intends to provide light on Qingdao's paternal genetic diversity and its evolutionary connections to other Han subgroups. SUBJECTS AND METHODS: The genetic polymorphisms of 41 Y-chromosomal short tandem repeat (STR) loci in the Qingdao Han were investigated using SureID® PathFinder Plus Kit. Phylogenetic studies were performed using genotype data from 52 East Asian groups at 23 common Y-STR loci. A multidimensional scaling plot and cladogram were constructed. Linear Discriminant Analysis (LDA) was carried out for predicting categories among the Han people. The k-nearest neighbour (kNN) algorithm was utilised to designate Y-SNP haplogroups for each haplotype. RESULTS: The Qingdao Han were genetically far from the Tibeto-Burman populations and close with the Han people from northern China. LDA indicated a deep integration among the present-day Han people. By the kNN model, the predicted O2a2 and O2a1 were shown to be the predominant Y-SNP haplogroups. CONCLUSIONS: This study would be helpful for reconstructing the patrilineal history in China and establishing a more comprehensive Y-STR database.

Understanding sovereignty through meteorology: China, Japan, and the dispute over the Qingdao Observatory, 1918-1931.

Concentrating on the Qingdao Observatory, this paper will explore the role of scientific facility in asserting China's sovereignty during the first half of the twentieth century. Although scholars have explained the efforts of China's internationalization in diplomacy through the perspectives of politics, economics and culture, they have not paid attention to science. Therefore, this paper aims to shed some light on how scientific issues were solved via diplomacy during the Republic of China, while further asserting that the focus in negotiations was not confined to science itself, but rather to sovereignty within a scientific context. In this process, the meaning of sovereignty has also been expanded basing on the improvement of nation's scientific capability. Besides, the participation of different actors involved in sovereignty assertion is investigated by this paper. Although the diplomatic negotiation was held at the international level, the local government and scientific community were main promoters in this case, which calls for attention on the various subjects in sovereignty issue. Consequently, this paper argues that Asian countries, such as Republic of China, could also employ science as a means to negotiate with foreign powers and claim their due rights.

Beach tourists behavior and beach management strategy under the ongoing prevention and control of the COVID-19 pandemic: A case study of Qingdao, China.

The sudden outbreak of COVID-19 has led beach tourism to a complete halt in January 2020, disrupting millions of livelihoods and businesses. Due to the economic importance of beach tourism, many governments reopened tourist beaches after the number of confirmed cases decreased. It is essential to open beaches orderly to meet the needs of tourists, maintain beach's health and restore coastal economy under the new reality. This paper selected Qingdao in China as a case study, drew on a questionnaire survey among beach tourists, summarized the effects of the COVID-19 on beach tourism industry and tourism enterprise, analyzed beach tourists' psychology and behavior, and developed beach management strategy under the ongoing prevention and control of COVID-19. The results showed that the COVID-19 pandemic caused severe damage to beach tourism which bases on travel and mobility, and this industry was temporarily suspended. With the changing epidemic situation, beach tourism witnessed a gradual recovery from stagnation to local tourism. Meanwhile, tourism enterprises were hit by the devastating impact of the COVID-19, causing problems such as business reduction, tense cash flow, high operating cost and unclear market prospect. Under the normalization of pandemic prevention, tourists did not have severe fear and anxiety about the pandemic, and placed great importance on the prevention and control measures, emergency measures and pandemic risk level of the beach destination. The pandemic also reshaped the perception and mode of beach tourism. Ecological tourism, travelling with family, and local tourism became the primary choices for tourists. Beach congestion, health status, and the quality of tourism services were the biggest concerns for tourists. Additionally, social media and short video APP became the new marketing channels. Finally, beach management strategies were proposed from the aspects of pandemic prevention and control, emergency management, information communication, tourist management, service management, and environmental management.

Process analysis of PM2.5 pollution events in a coastal city of China using CMAQ.

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 PM2.5 concentration in Qingdao during three representative PM2.5 pollution events in the winter of 2015 and 2016. Compared with the observed surface PM2.5 concentrations, CMAQ could reasonably reproduce the temporal and spatial variations of PM2.5 during these three events. Process analysis results show that primary emissions accounted for 72.7%-93.2% of the accumulation of surface PM2.5 before and after the events. When the events occurred, primary emissions were still the major contributor to the increase of PM2.5 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 PM2.5 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 PM2.5 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 PM2.5, when precipitation occurred.

A multi-biomarker approach in scallop Chlamys farreri to assess the impact of contaminants in Qingdao coastal area of China.

A multi-biomarker approach was carried out to classify the environmental quality and the adverse effects of contaminants on scallop Chlamys farreri. The scallops were collected from three sampling stations in Qingdao coastal area of China in March, May, August and October of 2015. A suite of environmental factors and biomarkers, including temperature, salinity, pH, the concentrations of polycyclic aromatic hydrocarbons (PAHs), tetrabromobisphenol A (TBBPA) and metals (Cr, Mn, Cu, Zn, Cd, Pb, As) in seawater and soft tissue, mRNA expression of aryl hydrocarbon receptor (AhR) and P-glycoprotein (P-gp), 7-ethoxyresorufin O-deethylase (EROD), glutathione-S-transferase (GST), uridine-diphosphate-glucuronyl-transferase (UGT), sulfotransferase (SULT), metallothionein (MT), Superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), lipid peroxidation (LPO) and protein carbonyl (PC) contents and DNA strand breaks, were measured in the gill and digestive gland. The results showed that S2 was the most polluted while S1 was identified the least polluted. Despite the differentiation of pollution levels and environmental parameters the selected biomarkers responded efficiently to contaminants. Principal component analysis (PCA) revealed that EROD for PAHs, AhR for TBBPA, MT for Cr, Pb and Mn, LPO and PC for Zn were the effective biomarkers respectively. This study demonstrated that the application of multi-biomarker approach in conjunction with the traditional analysis of environmental parameters and contaminants provided valuable information in environmental risk assessment.

Metatranscriptomic insights into the microbial metabolic activities during an Ulva prolifera green tide in coastal Qingdao areas.

Green tide, a typical marine environmental disaster that profoundly influenced the coastal areas, has been occurred consecutively in the South Yellow Sea of China since 2007. Herein, the active microbial community structure and metabolic pathways in Qingdao offshore during an Ulva prolifera green tide were investigated by using metatranscriptomic approach. The dominant active microbial taxa at the outbreak phase were primarily a functional group that can utilize organic matters derived from U. prolifera, such as Lentibacter, Polaribacter and Planktomarina. While the taxa involved in biogeochemical cycles, including Phaeobacter, Pseudomonas and Marinobacterium, dominated the active microbial communities at the decline phase. The expression level of enzymes involved in U. prolifera polysaccharides degradation was significantly higher at the outbreak phase compared to the decline phase. At the same time, the main players Glaciecola and Polarbacter showed similar trends, suggesting that the low competitiveness for nutrients of related microorganisms at this phase made them degrade more U. prolifera polysaccharides to meet their own nutrient needs, thereby accelerating the degradation of U. prolifera. According to KEGG annotation, the biogeochemical pathways including nitrogen cycle, sulfur cycle and methane oxidation altered during the green tide, with thiosulfate oxidation and methane oxidation probably being the crucial pathways at the outbreak and the decline phase respectively. The coupling of sulfide oxidation and denitrification was also observed in this study. Furthermore, the green tide in Qingdao offshore might impact the greenhouse effects induced by CH4 and N2O through influencing the related microbial processes.

Distribution and influencing factors of atmospheric nitrogen oxides (NOx) over the east coast of China in spring: Indication of the sea as a sink of the atmospheric NOx.

An integrated observation of NOx that included coastal cities and oceanic cruises covering the Qingdao coastal waters sites (QDCW) and the Yellow Sea and East China Sea sites (YECS) was conducted in spring. The average concentrations of the coastal cities, the QDCW, and the YECS were 5.4 ± 4.1, 4.2 ± 3.5, and 2.9 ± 6.8 ppb for NO while 18.5 ± 7.2, 9.4 ± 5.2, and 4.9 ± 6.4 ppb for NO2, depicting lowest levels in the open seas. Atmospheric NO and NO2 showed similar spatial variations over the seas, the stations where the air masses originated from land or nearshore regions showed higher levels, but the decisive influencing factors were not the same in the different study areas. The calculated NOx flux value in the YECS (-8.7 × 10-17 mol N cm-2) indicated that the sea surface was a net sink of atmospheric NOx.

Nutrient stoichiometric and resorption characteristics of the petals of four common urban greening Rosaceae tree species.

Objective: Nutrient resorption efficiency and stoichiometric ratios are important strategies for understanding plants. The present study examined whether or not the nutrient resorption process of plant petals is similar to that of leaves and other vegetative organs, as well as the nutrient restriction status of the whole flowering process of plants in urban ecosystems. Methods: Four Rosaceae tree species, Prunus yedoensis Matsum, Prunus serrulata var. lannesiana, Malus micromalus Makino, and Prunus cerasifera 'Atropurpurea', were selected as urban greening species to analyze the contents of C, N, P, and K elements in the petals and their stoichiometric ratios and nutrient resorption efficiencies. Results: The results show interspecific differences in nutrient contents, stoichiometric ratios, and nutrient resorption efficiency of the fresh petals and petal litter of the four Rosaceae species. The nutrient resorption process was similar to that of the leaves before the petals fell. The nutrient contents of petals were higher than that of leaves at the global level, but the stoichiometric ratio and nutrient resorption efficiency of petals were lower. According to the "relative resorption hypothesis", N was limiting during the entire flowering period. The nutrient resorption efficiency of petals was positively correlated with nutrient variation. The correlation between the nutrient resorption efficiency of petals with nutrient content and stoichiometric ratio of petal litter was stronger. Conclusion: The experimental results provide scientific basis and theoretical support for the selection, scientific maintenance and fertilization management of Rosaceae tree species in urban greening.

Report of the online meeting of the 7th Asian Conference on Environmental Mutagens (ACEM), China, November 5-6, 2022.

The 7th Asian Conference on Environmental Mutagens (ACEM 2022) was held online from November 5-6, 2022. However, the 19th Chinese Environmental Mutagen Society Meeting was postponed due to the pandemic prevention policies of COVID-19 and the time will be announced later. In total, 467 participants from 8 countries, including China, Japan, Korea, Philippines, etc. participated in the virtual conference. Eight keynote speakers and 16 lecturers in 2 symposia made their speeches online on topics aligned with the theme "The Impact of Global Change on Asian Environment and Genomic Health". More than 270 abstracts were submitted in this conference. We sincerely appreciate the efforts of all the participants, organizers, and members from Asian Association of Environmental Mutagen Societies (AAEMS). ACEM 2022 was a success and provided an excellent platform for exchanging the latest developments and stimulating scientific collaboration in the Asia-Pacific region as well as other parts of the world.

Rural Spatial Differentiation and Revitalization Approaches in China: A Case Study of Qingdao City.

Rural revitalization, as a major strategy with the goal of realizing the overall development of strong agriculture industries, beautiful rural areas, and rich farmers, is an effective way of alleviating the loss of talent, land, capital, and other elements in rural areas and a possible cure for "rural diseases". However, "rural diseases" faced by villages are very different, and thus exploring suitable strategies for rural revitalization is beneficial to the implementation of rural revitalization strategies and the promotion of urban-rural integration. Based on location theory, this paper constructs a point-axis-domain three-dimensional spatial location theory model that integrates market location, traffic location, and natural location and combines the coupling coordination model to comprehensively study the vitality and development directions of Qingdao's rural areas. Results found that Qingdao's high-level and medium-high-level coupling coordination areas are the main types of coupling coordination, accounting for 45.19% and 47.48%, respectively. Based on the development status of Qingdao, this study explores development directions for rural revitalization poles as well as high-level, medium-high-level, and medium-level coupling coordination areas and suggests the following: rural revitalization poles should play a demonstration role in rural revitalization in terms of industrial development, rural civilization, social governance, public service construction, etc.; high-level coupling coordination areas should focus on building modern hi-tech agriculture and rural marine tourism industries; medium-high-level coupling coordination areas should strengthen the building of satellite towns and promote industrial transformation and upgrading; medium-level coupling coordination areas should actively develop ecological environment conservation models and establish a characteristic mountainous eco-tourism industry. Thus, the findings provide important scientific reference for the implementation of rural revitalization.

Land Subsidence in Qingdao, China, from 2017 to 2020 Based on PS-InSAR.

Land subsidence is a global geological disaster that seriously affects the safety of surface and underground buildings/structures and even leads to loss of life and property. The large-scale and continuous long-time coverage of Interferometric Synthetic Aperture Radar (InSAR) time series analysis techniques provide data and a basis for the development of methods for the investigation and evolution mechanism study of regional land subsidence. Based on the 108 SAR data of Sentinel-1 from April 2017 to December 2020, this study used Persistent Scatterer InSAR (PS-InSAR) technology to monitor the land subsidence in Qingdao. In addition, detailed analysis and discussion of land subsidence combined with the local land types and subway construction were carried out. From the entire area to the local scale, the deformation analysis was carried out in the two dimensions of time and space. The results reveal that the rate of surface deformation in Qingdao from 2017 to 2020 was mainly -34.48 to 5.77 mm/a and that the cumulative deformation was mainly -126.10 to 30.18 mm. The subsidence areas were mainly distributed in coastal areas (along the coasts of Jiaozhou Bay and the Yellow Sea) and inland areas (northeast Laixi City and central Pingdu City). In addition, it was found that obvious land subsidence occurred near the Health Center Station of Metro Line 8, a logistics company in Qingdao, and near several high-rise residential areas and business office buildings. It is necessary for the relevant departments to take timely action to prevent and mitigate subsidence-related disasters in these areas.

Characterization and sources of trace elements in PM1 during autumn and winter in Qingdao, Northern China.

Atmospheric sub-micrometer particles (PM1, particles with an aerodynamic diameter ≤ 1.0 µm) monitoring in Qingdao, a coastal city in Northern China, was conducted for two consecutive years from November 1, 2018 to January 31, 2019 (hereafter referred to as OP2018-2019) and from October 28, 2019 to January 20, 2020 (hereafter referred to as OP2019-2020). The results showed that compared with OP2018-2019, the concentrations of V, Ni, As, Pb, and Cd in PM1 in OP2019-2020 decreased by 61.9%, 31.4%, 49.2%, 25.4%, and 27.1%, respectively. For the indicators of ship emission sources, a significant reduction in V (73.3%) and Ni (22.1%) concentrations were observed after the implementation of the updated Domestic Emission Control Area (DECA 2.0) policy for ships since January 1, 2019 proposed by the Ministry of Transportation. This result demonstrated that the implementation of the DECA 2.0 policy had a significant effect on reducing ship emissions. The Field Emission Scanning Electron Microscope analysis identified the impact of ship emission sources, while the inconsistent distribution of V and Ni revealed other potential sources of Ni. The V/Ni ratios during the pre-policy and post-policy periods decreased by 40.7%. Along with the further implementation of the domestic coastal ship pollution control zone policy, V/Ni ratio should be cautiously used as a parameter for ship emission sources. The positive matrix factorization method identified five source factors: coal combustion/biomass burning (47.8%), crustal sources (21.2%), vehicle exhaust/road dust (15.1%), industrial emissions (11.1%), and ship emissions (4.9%). The contribution rates of ship emission sources before and after the DECA 2.0 policy were analyzed and found to be 5.6% and 3.4%. The potential source contribution factor analysis of As showed that the potential emission source areas were significantly reduced in OP2019-2020, which might be related to the coal fired cleanup operations conducted in Beijing-Tianjin-Hebei and surrounding areas.

[Characteristics and Health Risk Assessment of Trace Elements in Atmospheric PM1 During Autumn and Winter in Qingdao].

From November 1,2018 to January 31,2019 (OP2018-2019) and from November 1,2019 to January 20, 2020 (OP2019-2020), PM1 measurement was conducted daily for two consecutive years. The concentration of trace elements in the atmospheric PM1 in Qingdao in autumn and winter was analyzed. The observation period was divided into four air quality levels (Level Ⅰ, Level Ⅱ, Level Ⅲ, and Level Ⅳ), and the characteristics and sources of the concentration of trace elements in PM1 were analyzed. The non-carcinogenic risks (Zn, Pb, Mn, Cu, and V) and carcinogenic risks (As, Cr, Ni, Cd, and Co) of different people with different air quality levels were evaluated. The results showed that the changes in total metal element concentrations were associated with changes in Ca, K, and Al concentrations at different air quality classes during OP2019-2020 compared to those during OP2018-2019 and were more influenced by dust and biomass combustion sources. Compared with that during OP2018-2019, the V concentration in different air quality levels (Level Ⅰ, Level Ⅱ, Level Ⅲ, and Level Ⅳ) during OP2019-2020 decreased by 19.0%, 60.5%, 82.7%, and 77.5%, respectively. This was presumed to be related to the implementation of the Domestic Emission Control Area (DECA) policy for ships, which led to the significant reduction in V concentration due to the change in fuel quality of ships in the waters around Qingdao. The results of the enrichment factor, the ratio method, and the backward trajectory of airflow further indicated that the changes in V concentrations were mainly influenced by the DECA policy. However, after the implementation of the DECA, the V/Ni value as a limit for judging the influence of ship sources in the area required further exploration. The health risk assessment results showed that the risk factor of Mn ranged from 0.07 to 1.22 during OP2018-2019 and OP2019-2020. It was recommended to strengthen the management and control of Mn-containing pollution sources. The lifetime carcinogenic risk (ILCR) value of As and Cd under different air qualities during OP2018-2019 and OP2019-2020 was lower than 10-4 but higher than 10-6, indicating that there was a carcinogenic probability, although it was still at an acceptable level. During OP2018-2019, when the air quality was Ⅳ, the ILCR value of Cr was higher than 10-4, and there was a risk of cancer.

Genetic Analysis of a Large-Scale Phaeocystis globosa Bloom Offshore Qingdao, China.

A sudden large-scale bloom event of the haptophyte Phaeocystis globosa that lasted over one month in the winter of 2021 was observed offshore Qingdao, China. This P. globosa bloom event was unusual as it was the first P. globosa bloom recorded in Qingdao offshore. Furthermore, the temperature at which this event occurred was much lower than that of previous P. globosa blooms in China. We hypothesize that the P. globosa strains that drove the development of this bloom offshore Qingdao were genetically unique and have a competitive advantage in the environmental conditions. To test this hypothesis, we analyzed P. globosa genetic diversity and the temporal dynamics of the bloom, using the high-resolution molecular markers pgcp1 and cox1 that we developed recently. The analysis revealed that the genetic compositions of P. globosa offshore Qingdao were rather limited, containing two dominant genotypes and other rare genotypes with low abundance, representing a small portion of the genetic diversities identified in coastal waters in China, and were rather different from the P. globosa genotypes outside of the Jiaozhou Bay before the P. globosa bloom in the winter of 2021. This suggested only certain strains contribute to the development of blooms under certain environmental conditions. The genetic composition may indicate the unusual timing and scale of this P. globosa event.

[Pollution Characteristics and Source Analysis of Atmospheric PM2.5-bound Polycyclic Aromatic Hydrocarbons in a Port Area].

In order to explore the pollution characteristics and potential sources of polycyclic aromatic hydrocarbons (PAHs) in the polluted air of a port area, PM2.5 samples (n=59) were collected from Qingdao Port for four seasons from August 2018 to May 2019. The seasonal variation and composition characteristics of PM2.5-bound PAHs were analyzed, the influence of meteorological factors on PAH concentrations was explored using correlation analysis, and the potential sources were analyzed using positive definite matrix factorization and potential source contribution function models. The results showed that the total mean concentration of PAHs was (8.11±12.31) ng·m-3, which was higher in autumn and winter than that in spring and summer. The seasonal molecular compositions of PAHs were similar, dominated by 4-5 ring PAHs (75.43%). Fluoranthene, benzo[e]pyrene, benzo[a]anthracene, phenanthrene, pyrene, and chrysene were the dominant species of PAHs in the study area, which are similar to the major compounds in ship exhaust. Correlation analysis showed that PAH concentrations were significantly negatively correlated with temperature and relative humidity and significantly positively correlated with atmospheric pressure and wind direction and had a poor correlation with wind speed. PMF analysis extracted six contribution factors, and the results indicated that Qingdao Port was mainly influenced by shipping emissions (28.83%), followed by vehicle emissions (20.49%), as well as crude oil volatilization (13.47%). Summer had the greatest impact on shipping emissions. The PSCF results suggested that Beijing-Tianjin-Hebei, Bohai Rim, and northern Shandong were the main source regions for long-range transport.