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Urban air quality evaluations under two versions of the national ambient air quality standards of China
2016
Chen, Wei | Tang, Hongzhao | Zhao, Haimeng
The air quality of urban areas is of a great concern for residents living in cities. China has released a new National Ambient Air Quality Standard (NAAQS) in 2012 to improve the air quality evaluation index because the reported air quality situation from governments is inconsistent with public sensing. In total, 190 cities' hourly monitoring data are publicized in the national web platform. By using the above data, the air pollution indexes (APIs) under the previous NAAQS and air quality indexes (AQI) for all 190 cities' were calculated. With the new NAAQS, the national attainment rate has fallen from 73.63% to 59.62% with regional differences. 8 of the 10 cities with the worst air quality are located in North China around Beijing, while 9 of the 10 cities with the best air quality are located in South China. These results indicate that cities in North China, including Beijing, need to address the air pollution together as the pollution in North China is a regional issue and not a local issue.
Afficher plus [+] Moins [-]The changing dynamics of coral reef science in Arabia
2016
Vaughan, Grace O. | Burt, John A.
Six percent of the world's coral reefs occur around the Arabian Peninsula, providing a valuable ecological, economic and scientific resource for the nations bordering its shores. We provide the first region-wide assessment of the current status and historical trends in coral reef research, focusing on research in the Red Sea, Arabian Sea, and Arabian Gulf. In total, 633 regional reef publications have been produced since the 1930s, covering a wide variety of themes and taxa. Our results show a great deal of commonality in regional reef research, but also highlight important differences in research among the various seas as well as knowledge gaps that represent opportunities for future research. A regionally-integrated approach to future research is essential. There is a growing need for large-scale research to guide management of reefs and their stressors, as these operate at much larger scales than the national borders within which most research currently occurs.
Afficher plus [+] Moins [-]Method and application of ocean environmental awareness measurement: Lessons learnt from university students of China
2016
Umuhire, Marie Louise | Fang, Qinhua
Different studies have proved that enhancing public Ocean Environmental Awareness (OEA) will lead to increased public support for ocean environmental protection. Our study develops a questionnaire to investigate current levels of students’ OEA from three aspects including ocean environmental concerns, ocean environment knowledge and willingness to participate in ocean related activities. This questionnaire was applied to students from Xiamen University to understand the OEA of university students in China, of which there are few studies. Using data gathered from a random purposive sample, the OEA level of students in Xiamen University was investigated and then the influencing factors (education, geographical situation, age and gender etc.) were further analyzed. Findings suggest that most students are concerned about the ocean environment but their knowledge is not enough that makes the willingness to participate in ocean related actions limited as well. The results show there is an urgent need to improve students’ OEA.
Afficher plus [+] Moins [-]Estimation of mercury background values in sediment and biota of the Bijagós archipelago, Guinea-Bissau
2016
Coelho, J.P. | Monteiro, R.J.R. | Catry, T. | Lourenço, P.M. | Catry, P. | Regalla, A. | Catry, I. | Figueira, P. | Pereira, E. | Vale, C. | P.Granadeiro, José
This work evaluates the mercury (Hg) contamination status (sediments and biota) of the Bijagós archipelago, off the coast of Guinea-Bissau. Sediments exhibited very low concentrations (<1–12ngg−1), pointing to negligible sources of anthropogenic Hg in the region. Nevertheless, Hg is well correlated to the fine fraction, aluminium, and loss on ignition, indicating the effect of grain size and organic matter content on the presence of Hg in sediments. Mercury in the bivalves Tagelus adansoni and Senilia senilis did not vary considerably among sites, ranging within narrow intervals (0.09–0.12 and 0.12–0.14μgg−1 (dry weight), respectively). Divergent substrate preferences/feeding tactics may justify slight differences between species. The value 11ngg−1 is proposed as the sediment background concentration for this West-African coastal region, and concentrations within the interval 8–10ngg−1 (wet weight) may be considered as reference range for S. senilis and T. adansoni in future monitoring studies.
Afficher plus [+] Moins [-]Spatial distribution and pollution evaluation of heavy metals in Yangtze estuary sediment
2016
Liu, Ruimin | Men, Cong | Liu, Yongyan | Yu, Wenwen | Xu, Fei | Shen, Zhenyao
To analyze the spatial distribution patterns and ecological risks of heavy metals, 30 sediment samples were taken in the Yangtze River Estuary (YRE) in May 2011. The content of Al, As, Cr, Cu, Fe, Mn, Ni and Pb increased as follows: inner-region<river mouth<adjacent sea. According to Igeo and RI, As, Cr and Cd were the main pollutants. What is more, the greatest contaminated area appeared at the river mouth of the south branch of YRE. In Tucker 3, considering the fractions of metals, Mn turned to be the severest pollutant and As did not contribute too much to the contamination of the YRE. That was most probably because that Mn was closely related to the carbonate-associated (CARB) and As was related to organic-associated (OM) which is more stable than CARB. The fractions played an important role in the contamination assessment of heavy metals.
Afficher plus [+] Moins [-]Polycyclic aromatic hydrocarbons in surface sediments from the Coast of Weihai, China: Spatial distribution, sources and ecotoxicological risks
2016
Zhang, Daolai | Liu, Jinqing | Yin, Ping | Lin, Xuehui | Liu, Na | Meng, Xianwei
This study was conducted to measure the polycyclic aromatic hydrocarbon (PAH) concentrations and evaluate the distribution, sources in surface sediments from various coastal sites in Weihai, which create good conditions for rapid development because of their excellent geographical location and abundant marine resources. The results indicated that the total PAHs contents in the sediments of Weihai ranged from 2.69 to 166.50ngg−1, with an average of 67.44ngg−1. Phenanthrene, Fluoranthene, Benzo(b)fluoranthene, Chrysene, and Pyrene were dominant in sediments, primarily as a result of high temperature combustion and biomass. Molecular ratios suggested that these PAHs in the sediments of Weihai were predominantly from pyrogenic sources such as grass, wood and charcoal combustion, as well as engine exhaust which is similar to the result of the study of the Yellow River Delta, China. The result of probability risk assessment additionally elucidated low PAH ecological risk in the surface sediments of Weihai, China.
Afficher plus [+] Moins [-]Assessing exemptions under the ballast water management convention: preclude the Trojan horse
2016
Olenin, Sergej | Ojaveer, Henn | Minchin, Dan | Boelens, Rick
The International Maritime Organization (IMO) Ballast Water Management Convention (BWMC) is a powerful instrument aimed at reducing spread of harmful aquatic organisms and pathogens (HAOPs). As BWMC is expected to enter into force soon, shipping companies will start seeking exemptions for ballast water management in accordance with BWMC Regulation A-4. However, without scientifically robust risk assessment (RA) and consistent rules, the exemptions may introduce a new form of risk within a convention generally designed to reduce risks. This paper describes an adaptive system for granting exemptions, consisting of six major components: target species selection procedure, port-to-port RA, monitoring, information support, administrative decision and review process. The system is based on key principles defined in the IMO guidelines for RA and is designed to continuously accumulate evolving experience on granting exemptions. The ultimate goal is to contribute to the control of the spread of HAOPs, without placing an unnecessary burden on the shipping industry.
Afficher plus [+] Moins [-]Levels, distributions and sources of veterinary antibiotics in the sediments of the Bohai Sea in China and surrounding estuaries
2016
Liu, Xinghua | Zhang, Haibo | Li, Lianzhen | Fu, Chuancheng | Du, Zhen | Huang, Yujuan | Wu, Longhua | Tang, Jianhui | Luo, Yongming | Christie, Peter
Veterinary antibiotics are emerging contaminants of concern. A total of 139 samples comprising 104 marine sediments and 35 estuarine sediments were collected from the Bohai Sea area and analyzed for seventeen antibiotics. The results reveal that the presence and concentration of antibiotics were generally higher in the estuaries than in the sea. The highest antibiotic concentration, 4695μgkg−1 of oxytetracycline, occurred in the estuarine sediment from Ziya New River. Bohai Bay and Laizhou Bay and the surrounding estuaries had higher concentrations of antibiotics. However, low levels of antibiotics detected were detected in Liaodong Bay in contrast to the high concentrations present in the surrounding estuaries. Spatial heterogeneity and principal component analysis suggest a large impact of terrestrial sources of the antibiotics contaminating the Bohai Sea. Risk quotients indicate that current levels of norfloxacin and oxytetracycline might be potentially hazardous to sensitive biota both in the Bohai Sea and in its surrounding estuaries.
Afficher plus [+] Moins [-]Enhanced biodegradation of pyrene and indeno(1,2,3-cd)pyrene using bacteria immobilized in cinder beads in estuarine wetlands
2016
Huang, Ru-ying | Tian, Wei-jun | Liu, Qing | Yu, Hui-bo | Jin, Xin | Zhao, Yang-guo | Zhou, Yu-hang | Feng, Gong
Two strains (Pseudomonas taiwanensis PYR1 and Acinetobacter baumannii INP1) were isolated from PAH-contaminated Liaohe estuarine wetland using enrichment. The cells of PYR1 and INP1 were immobilized in cinder beads for pyrene and indeno(1,2,3-cd)pyrene biodegradation in wetland. Biodegradation of pyrene and indeno(1,2,3-cd)pyrene in soils from wetland was carried out in pots using free cells as well as those immobilized in cinder beads to ascertain the role of bioaugmentation. Supported by the cinder beads, the immobilized cells degraded 70.7% and 80.9% of pyrene and indeno(1,2,3-cd)pyrene respectively after 30days. While the free cells degraded only 58.2% and 55.3%. Additionally, microbial analysis with high-throughput sequencing revealed the changes of microbial communities in soil without and with cinder beads immobilized with strains. The result indicated that Gammaproteobacteria were dominant PAH-degrading groups during bioaugmentation. This effective approach can be used to treat other PAH-contaminated wetlands by immobilizing different species of bacteria in cinder beads.
Afficher plus [+] Moins [-]Biodegradation potentiality of psychrophilic bacterial strain Oleispira antarctica RB-8T
2016
Gentile, G. | Bonsignore, M. | Santisi, S. | Catalfamo, M. | Giuliano, L. | Genovese, L. | Yakimov, M.M. | Denaro, R. | Genovese, M. | Cappello, S.
The present study is focused on assessing the growth and hydrocarbon-degrading capability of the psychrophilic strain Oleispira antarctica RB-8T. This study considered six hydrocarbon mixtures that were tested for 22days at two different cultivation temperatures (4 and 15°C). During the incubation period, six sub-aliquots of each culture at different times were processed for total bacterial abundance and GC–FID (gas chromatography–flame ionization detection) hydrocarbon analysis.Results from DNA extraction and DAPI (4′,6-diamidino-2-phenylindole) staining showed a linear increase during the first 18days of the experiment in almost all the substrates used; both techniques showed a good match, but the difference in values obtained was approximately one order of magnitude. GC–FID results revealed a substantial hydrocarbon degradation rate in almost all hydrocarbon sources and in particular at 15°C rather than 4°C (for commercial oil engine, oily waste, fuel jet, and crude oil). A more efficient degradation was observed in cultures grown with diesel and bilge water at 4°C.
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