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Environmental variabilities and the distribution of octocorals and black corals in Hong Kong
2014
Yeung, C.W. | Cheang, C.C. | Lee, M.W. | Fung, H.L. | Chow, W.K. | Ang, P.
A recent comprehensive survey covering 125 sites in Hong Kong waters recorded 29 soft coral species in 14 genera, 38 species of gorgonians in 19 genera and six species of black corals in two genera. Environmental variabilities based on water quality data collected by Hong Kong Environmental Protection Department were analyzed using multivariate statistics to find variables that are significantly correlated with coral distribution patterns. Eleven water quality zones with similar environmental variabilities were recognized, which could further be classified into five groups, namely Inner Bay, Outer Bay, Eastern, Western and Southern waters. LINKTREE analysis provided an overall trend indicating the importance of salinity, sediment and nutrient loadings in affecting octocoral and black coral distribution from west to east of Hong Kong waters, and from inner to outer bays. Furthermore, water turbidity and wave exposure could also affect the coral distribution patterns from north, northeast to southern waters.
Afficher plus [+] Moins [-]Emerging organic contaminants in coastal waters: Anthropogenic impact, environmental release and ecological risk
2014
Jiang, Jheng-Jie | Lee, Chon-Lin | Fang, Meng-Der
This study provides a first estimate of the sources, distribution, and risk presented by emerging organic contaminants (EOCs) in coastal waters off southwestern Taiwan. Ten illicit drugs, seven nonsteroidal anti-inflammatory drugs (NSAIDs), five antibiotics, two blood lipid regulators, two antiepileptic drugs, two UV filters, caffeine, atenolol, and omeprazole were analyzed by solid-phase extraction and liquid chromatography coupled to tandem mass spectrometry (SPE–LC–MS/MS). Thirteen EOCs were detected in coastal waters, including four NSAIDs (acetaminophen, ibuprofen, ketoprofen, and codeine), three antibiotics (ampicillin, erythromycin, and cefalexin), three illicit drugs (ketamine, pseudoephedrine, and MDMA), caffeine, carbamazepine, and gemfibrozil. The median concentrations for the 13 EOCs ranged from 1.47ng/L to 156ng/L. Spatial variation in concentration of the 13 EOCs suggests discharge into coastal waters via ocean outfall pipes and rivers. Codeine and ampicillin have significant pollution risk quotients (RQ>1), indicating potentially high risk to aquatic organisms in coastal waters.
Afficher plus [+] Moins [-]Population dynamics and antimicrobial susceptibility of Aeromonas spp. along a salinity gradient in an urban estuary in Northeastern Brazil
2014
Silva, Camila Magalhães | Evangelista-Barreto, Norma Suely | Vieira, Regine Helena Silva dos Fernandes | Mendonça, Kamila Vieira | Sousa, Oscarina Viana de
The main objective of this study was to quantify population and identify culturable species of Aeromonas in sediment and surface water collected along a salinity gradient in an urban estuary in Northeastern Brazil. Thirty sediment samples and 30 water samples were collected from 3 sampling locations (A, B and C) between October 2007 and April 2008. The Aeromonas count was 10–7050CFU/mL (A), 25–38,500CFU/mL (B) and<10CFU/mL (C) for water samples, and ∼100–37,500CFU/g (A), 1200–43,500CFU/g (B) and<10CFU/g (C) for sediment samples. Five species (Aeromonas caviae, A. sobria, A. trota, A. salmonicida and A. allosaccharophila) were identified among 41 isolates. All strains were sensitive to chloramphenicol and ceftriaxone, whereas 33 (80, 4%) strains were resistant to at least 2 of the 9 antibiotics tested. Resistance to erythromycin was mostly plasmidial. In conclusion, due to pollution, the Cocó River is contaminated by pathogenic strains of Aeromonas spp. with a high incidence of antibacterial resistance, posing a serious risk to human health.
Afficher plus [+] Moins [-]Selective transport of microplastics and mesoplastics by drifting in coastal waters
2014
Isobe, Atsuhiko | Kubo, Kenta | Tamura, Yuka | Kako, Shin’ichio | Nakashima, Etsuko | Fujii, John N.
The quantity and size distributions of small plastic fragments in the Seto Inland Sea, Japan were investigated using field surveys and a numerical particle-tracking model. The model was used to interpret the distributions of small plastic fragments and the possible transport processes in coastal waters. Of note, the size and quantity of mesoplastics (approximately >5mm) gradually increased close to the coast irrespective of the existence of river mouths, which probably act as a major source of anthropogenic marine debris. Additionally, microplastics were more dominant as we moved further offshore. The numerical model reproduced the near-shore trapping of mesoplastics, suggesting that mesoplastics are selectively conveyed onshore by a combination of Stokes drift and terminal velocity, dependent on fragment sizes. It is suggested that mesoplastics washed ashore on beaches degrade into microplastics, and that the microplastics, which are free from near-shore trapping, are thereafter spread offshore in coastal waters.
Afficher plus [+] Moins [-]A novel best practices approach: The MARLISCO case
2014
Loizidou, Xenia I. | Loizides, Michael I. | Orthodoxou, Demetra L.
Research that was undertaken to identify and evaluate best practices that can effectively minimise the amount of marine litter in European Seas is presented. Best practices were approached in a novel way that aimed to maximise the impact and added value of the FP7-funded project MARLISCO. The practices served as a tool to enhance the active participation and build capacity in key actors through the implementation of the innovative, dedicatedly-developed decision support tool, DeCyDe-4-Marlisco.This paper also presents the key ‘preference’ attributes of successful marine litter management practices and provides a snapshot of the key characteristics of the recorded best practices as a means of helping the reader, and particularly decision makers, recognise what would make their marine litter management efforts more successful.
Afficher plus [+] Moins [-]Lost opportunities: Coral recruitment does not translate to reef recovery in the Florida Keys
2014
van Woesik, Robert | Scott, William J. | Aronson, Richard B.
We tested the hypothesis that the poor recovery of the coral populations on reefs in the Florida Keys is related to low coral recruitment. In the summer of 2011, we deployed 240 terracotta tiles at eight study sites in a balanced design: (i) among three depths; and (ii) between fished and unfished reefs. Corals recruited to ∼40% of the deployed tiles, with more corals settling on tiles on unfished reefs than on fished reefs. The apparent effect of protection was not a consequence of different densities of herbivorous fishes, but was more likely related to local hydrography and the tendency of the no-take reserves to act as larval sinks, particularly in the lower Florida Keys. There was a mismatch between the coral taxa that recruited and the adult coral assemblages, suggesting that recruits were arriving but not surviving to contribute to coral recovery.
Afficher plus [+] Moins [-]Biodegradation of nitrobenzene in a lysogeny broth medium by a novel halophilic bacterium Bacillus licheniformis
2014
Li, Tian | Deng, Xinping | Wang, Jinjun | Chen, Yucheng | He, Lin | Sun, Yuchuan | Song, Caixia | Zhou, Zhifeng
The Bacillus licheniformis strain YX2, a novel nitrobenzene-degrading halophilic bacterium, was isolated from active sludge obtained from a pesticide factory. Strain YX2 can withstand highly acidic and alkaline conditions and high temperatures. Degradation of nitrobenzene (200mgL−1) by YX2 exceeded 70% after 72h in lysogeny broth medium (pH 4–9). Under optimal degradation conditions (33°C, pH 7 in LB medium) YX2 degraded 50, 100, 200, and 600mgL−1 nitrobenzene within 36, 36, 72, and 156h, respectively. Even in the presence of benzene, phenol or aniline, strain YX2 efficiently degraded nitrobenzene. Furthermore, strain YX2 completely degraded 600mgL−1 nitrobenzene in 7% NaCl (w/w). Thus, our data show that strain YX2 may have promise for removing nitrobenzene from complex wastewaters with high salinity and variable pH.
Afficher plus [+] Moins [-]Variability of factors driving spatial and temporal dispersion in river plume and Chattonella antiqua bloom in the Yatsushiro Sea, Japan
2014
Aoki, Kazuhiro | Onitsuka, Goh | Shimizu, Manabu | Kuroda, Hiroshi | Matsuo, Hitoshi | Kitadai, Yuuki | Sakurada, Kiyonari | Ando, Hidenori | Nishi, Hiromi | Tahara, Yoshio
The dynamics of river plume in relation to harmful blooms of the raphidophycean flagellate, Chattonella antiqua in summer 2008–2010 in the Yatsushiro Sea, Japan were studied using a hydrodynamic model and monitoring data. In the southern area, the bloom formed in the waters stratified by a halocline caused by the southward expansion of riverine water from the Kuma River after the bloom initially forming in the northern area. The timing of the southward riverine water advection can be explained by the balance between the wind stress term and the pressure gradient term calculated from the horizontal density difference between the northern and southern areas. The wind stress and pressure gradient terms were evaluated using the sea surface temperature, salinity, wind speed and direction at two stations. Real time monitoring or continuous observations in these areas will enable nowcasts of bloom expansion when a bloom develops in the northern area.
Afficher plus [+] Moins [-]Marine legislation – The ultimate ‘horrendogram’: International law, European directives & national implementation
2014
Boyes, Suzanne J. | Elliott, Michael
The EU is a pre-eminent player in sustainable development, adopting more than 200 pieces of legislation that have direct repercussions for marine environmental policy and management. Over five decades, measures have aimed to protect the marine environment by tackling the impact of human activities, but maritime affairs have been dealt with by separate sectoral policies without fully integrating all relevant sectors. Such compartmentalisation has resulted in a patchwork of EU legislation and resultant national legislation leading to a piecemeal approach to marine protection. These are superimposed on international obligations emanating from UN and other bodies and are presented here as complex ‘horrendograms’ showing the complexity across vertical governance. These horrendograms have surprised marine experts despite them acknowledging the many uses and users of the marine environment. Encouragingly since 2000, the evolution in EU policy has progressed to more holistic directives and here we give an overview of this change.
Afficher plus [+] Moins [-]Impact of rainfall on the hygienic quality of blue mussels and water in urban areas in the Inner Oslofjord, Norway
2014
Tryland, Ingun | Myrmel, Mette | Østensvik, Øyvin | Wennberg, Aina C. | Robertson, Lucy J.
The effects of precipitation on the hygienic quality of water and blue mussels collected from five different localities in the urban areas in the Inner Oslofjord were investigated, with samples analysed for Escherichia coli, Salmonella spp., pathogenic Vibrio spp., Norovirus, Sapovirus, Cryptosporidium spp. and Giardia duodenalis. The sampling sites were located at varying distances from the outlet of combined sewer overflows (CSO)-impacted rivers/streams. In general, 1–3 log10 increases in fecal indicator bacteria and human pathogens were observed after heavy rainfalls. Blue mussels appeared to be a useful indicator of the impact of sewage at these sites, and generally a good correlation was identified between concentrations of E. coli and other human pathogens in the mussels. Provision of general advice to the public of avoiding areas near the outlets of CSO-impacted rivers after heavy rainfall may reduce the risk of gastroenteritis by bathers and others that may swallow water during recreational activities.
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