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The need for a formalised system of Quality Control for environmental policy-science
2018
Research science used to inform public policy decisions, herein defined as “Policy-Science”, is rarely subjected to rigorous checking, testing and replication. Studies of biomedical and other sciences indicate that a considerable fraction of published peer-reviewed scientific literature, perhaps half, has significant flaws. To demonstrate the potential failings of the present approaches to scientific Quality Control (QC), we describe examples of science associated with perceived threats to the Great Barrier Reef (GBR), Australia. There appears a serious risk of efforts to improve the health of the GBR being directed inefficiently and/or away from the more serious threats. We suggest the need for a new organisation to undertake quality reviews and audits of important scientific results that underpin government spending decisions on the environment. Logically, such a body could also examine policy science in other key areas where governments rely heavily upon scientific results, such as education, health and criminology.
Afficher plus [+] Moins [-]Microplastics analysis in Malaysian marine waters: A field study of Kuala Nerus and Kuantan
2018
Khalik, Wan Mohd Afiq Wan Mohd | Ibrahim, Yusof Shuaib | Tuan Anuar, Sabiqah | Govindasamy, Sharumathiy | Baharuddin, Nor Fadilah
The first report on the emergence of microplastic in Malaysian marine waters was documented in this study. Water samples were collected from two regions, namely Kuala Nerus and Kuantan port, as the representatives of different anthropogenic activities. Identification of microplastic was performed based on physical characteristics (colour, shape, density) and chemical characterisation (ATR-FTIR analysis) for a functional group of polymers. Fragment type, black or grey colour and high density (>1.02 g cm−3) of microplastic were the most prevalent characteristics found in both areas. Two principal components (density and colour) rendered explained about 95.3% (Kuantan) and 95.6% (Kuala Nerus) of the total variance. Six possible polymer materials were identified, namely polyester, polystyrene, polyamide, polyvinyl chloride, polypropylene, and polyethylene. The findings of the study provided good baseline information on marine debris issue in Malaysia.
Afficher plus [+] Moins [-]Natural radioactivity in the beach sand and soil along the coastline of Guangxi Province, China
2018
Liu, Xinming | Lin, Wuhui
Natural radioactivity in the beach sand and soil was measured and evaluated in typical ecosystems of mangroves, seagrasses, and coral reefs along the coastline of Guangxi Province, China. Radioactivity in the soil was about three times higher than that in the beach sand probably due to the distinct mineral components and particle sizes. A comparison with natural radioactivity levels in the global beach sands indicated that the beach sand of Guangxi had the lowest radioactivity. Radiological parameters including radium equivalent activity (Raeq), external and internal hazard indices (Hex and Hin), representative gamma level index (Iγr), absorbed gamma dose rate (DR), and annual effective dose equivalent (AEDE) were lower than the recommended values. Our results provide baseline data on radioactivity in the beach sand and soil along the coastline of Guangxi and contribute to the database of radioactivity in the global beach sand.
Afficher plus [+] Moins [-]Overall bacterial community composition and abundance of nitrifiers and denitrifiers in a typical macrotidal estuary
2018
Zhu, Weijing | Wang, Cheng | Sun, Faqian | Zhao, Liancheng | Dou, Wenjie | Mao, Zhihua | Wu, Weixiang
Coupled nitrogen cycling processes can alleviate the negative effects of eutrophication caused by excessive nitrogen load in estuarine ecosystems. The abundance and diversity of nitrifiers and denitrifiers across different environmental gradients were examined in the sediment of Hangzhou Bay. Quantitative PCR and Pearson's correlation analyses suggested that the bacterial ammonia-oxidizers (AOB) were the dominant phylotypes capable of ammonia oxidation, while the nirS-encoding denitrifiers predominated in the denitrification process. Simultaneously, nitrite and pH were found to be the two major factors influencing amoA and nir gene abundances, and the distribution of bacterial communities. Moreover, the ratio of nirS/AOB amoA gene abundance showed negative correlation with nitrite concentration. Fluorescence in situ hybridization further demonstrated that AOB and acetate-denitrifying cells were closely connected and formed obvious aggregates in the sediment. Together, all these results provided us a preliminary insight for coupled nitrification-denitrification processes in the sediment of Hangzhou Bay.
Afficher plus [+] Moins [-]Exploring public views on marine litter in Europe: Perceived causes, consequences and pathways to change
2018
Hartley, Bonny L. | Pahl, Sabine | Veiga, Joana | Vlachogianni, Thomais | Vasconcelos, Lia | Maes, Thomas | Doyle, Tom | d'Arcy Metcalfe, Ryan | Öztürk, Ayaka Amaha | Di Berardo, Mara | Thompson, Richard C.
Marine litter is a global challenge and society plays an important role via lifestyles and behaviour, including policy support. We analysed public perceptions of marine litter and contributing factors, using data from 1133 respondents across 16 European countries. People reported high levels of concern about marine litter, and the vast majority (95%) reported seeing litter when visiting the coast. The problem was attributed to product and packaging design and behaviour rather than lack of facilities or accidental loss of items. Retailers, industry and government were perceived as most responsible, but also least motivated and competent to reduce marine litter, whereas scientists and environmental groups were perceived as least responsible but most motivated and competent. Regression analyses demonstrated the importance of psychological factors such as values and social norms above sociodemographic variables. These findings are important for communications and interventions to reduce inputs of marine litter to the natural environment.
Afficher plus [+] Moins [-]Litter impacts on beach/dune systems along the Atlantico Department, the Caribbean Coastline of Colombia
2018
Rangel-Buitrago, Nelson | Castro-Barros, Julian Dario | Adriana Gracia, C. | Villadiego, Jose Dario Villamil | Williams, Allan T.
Eight beach/dune systems located along the Atlantico Department, Caribbean coast of Colombia were surveyed to determine litter influences over its scenic quality. Application of the Coastal Scenic Evaluation System (CSES) categorized these systems into two of the five available classes. Five of the investigated beach/dune systems belong to Class IV, while three systems correspond to V. Classes I, II and III were not found. Along these beach/dune systems, a total amount of 1908 litter items were collected with average abundances of 4.2 items/m2. Currently, 82% of surveyed sites are under an unacceptable condition of cleanness. User's habits as well as bad litter management practices are directly responsible for the decline of scenic quality of the Atlantico Department beach/dune systems. Litter management must be centered on strategies to eliminate or minimize litter sources. Specific remedial actions need to be defined and developed.
Afficher plus [+] Moins [-]In situ release rates of Cu and Zn from commercial antifouling paints at different salinities
2018
Antifouling paints are environmentally risk assessed based on their biocidal release rates to the water phase. In situ release rates of copper (Cu) and zinc (Zn) were derived for five commercial paints in two recreational marinas with different salinities (5 and 14 PSU) using an X-Ray Fluorescence spectrometer (XRF). Salinity was found to significantly affect the Cu release, with twice the amount of Cu released at the higher salinity, while its influence on the Zn release was paint-specific. Site-specific release rates for water bodies with salinity gradients, e.g. the Baltic Sea, are therefore necessary for more realistic risk assessments of antifouling paints. Furthermore, the in situ release rates were up to 8 times higher than those generated using standardized laboratory or calculation methods. The environmental risk assessment repeated with the field release rates concludes that it is questionable whether the studied products should be allowed on the Swedish market.
Afficher plus [+] Moins [-]Evaluation of the ability of calcite, bentonite and barite to enhance oil dispersion under arctic conditions
2018
A test program was conducted at laboratory and pilot scale to assess the ability of clays used in drilling mud (calcite, bentonite and barite) to create oil-mineral aggregates and disperse crude oil under arctic conditions. Laboratory tests were performed in order to determine the most efficient conditions (type of clay, MOR (Mineral/Oil Ratio), mixing energy) for OMA (Oil Mineral Aggregate) formation. The dispersion rates of four crude oils were assessed at two salinities. Dispersion was characterized in terms of oil concentration in the water column and median OMA size. Calcite appeared to be the best candidate at a MOR of 2:5. High mixing energy was required to initiate OMA formation and low energy was then necessary to prevent the OMAs from resurfacing. Oil dispersion using Corexit 9500 was compared with oil dispersion using mineral fines.
Afficher plus [+] Moins [-]Ingestion and fragmentation of plastic carrier bags by the amphipod Orchestia gammarellus: Effects of plastic type and fouling load
2018
Hodgson, D.J. | Bréchon, A.L. | Thompson, R.C.
Inappropriate disposal of plastic debris has led to the contamination of marine habitats worldwide. This debris can be ingested by organisms; however, the extent to which chewing and gut transit modifies plastic debris is unclear. Detritivores, such as amphipods, ingest and shred natural organic matter and are fundamental to its breakdown. Here we examine ingestion and shredding of plastic carrier bags by Orchestia gammarellus. A laboratory experiment showed these amphipods shredded plastic carrier bags, generating numerous microplastic fragments (average diameter 488.59μm). The presence of a biofilm significantly increased the amount of shredding, but plastic type (conventional, degradable and biodegradable) had no effect. Subsequent field observations confirmed similar shredding occurred on the strandline. Rates of shredding will vary according to amphipod density; however, our data indicates that shredding by organisms could substantially accelerate the formation microplastics in the environment.
Afficher plus [+] Moins [-]Spatial and vertical distribution of radiocesium in seawater of the East China Sea
2018
Zhao, Lijun | Liu, Dantong | Wang, Jinlong | Du, Jinzhou | Hou, Xiaolin | Jiang, Yifei
The 137Cs activity in surface water of the East China Sea (ECS) was 0.66–1.36 Bq m−3 during May of 2011. The low activities were observed in the Changjiang Estuary and Zhejiang-Fujian coast and high activities were observed in the south offshore and Kuroshio Current pathway, suggesting that the influence from the current system in the ECS. The 134Cs were undetectable (<0.03 Bq m−3) and the contribution of the Fukushima accident to ECS is estimated to be below 3%; hence it is negligible during the investigation period. Using the vertical profiles of 137Cs in the ECS, the mass balance is obtained, which suggests that the oceanic input dominates the 137Cs source in the ECS. 137Cs is potentially useful to trace water mass movement in the ECS. Our study provides comprehensive baseline of 137Cs in the ECS for evaluation of the possible influence of the nuclear power plants in the future.
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