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Fighting Nemo: Effect of 17α-ethinylestradiol (EE2) on aggressive behavior and social hierarchy of the false clown anemonefish Amphiprion ocellaris 全文
2017
Chen, Te-Hao | Hsieh, Chun-Yu
Aggressive behavior is crucial for maintaining social hierarchy in anemonefish. Endocrine disrupting chemicals such as EE2 may affect fish social hierarchy via disrupting their aggression. In this study, we aimed to characterize the effects of 17α-ethinylestradiol (EE2) on aggressive behavior and social hierarchy in the false clown anemonefish (Amphiprion ocellaris). In the laboratory experiment, juvenile anemonefish were randomly distributed to separated tanks to form small colonies of three individuals and were fed with EE2-dosed diet (100ng/g food) or a control diet for 90d. Through the experiment, each tank was videotaped and behavioral indicators of social status, including aggressive behavior, submissive response, and shelter utilization, were quantitatively analyzed from the videos. The EE2 exposure caused a higher frequency of intra-colonial aggressive interactions and a less stable social hierarchy. Our findings demonstrate the importance of examining the effects of endocrine disrupting chemicals on the social behavior of coral reef fish.
显示更多 [+] 显示较少 [-]The porewater nutrient and heavy metal characteristics in sediment cores and their benthic fluxes in Daya Bay, South China 全文
2017
Ni, Zhixin | Zhang, Ling | Yu, Shuo | Jiang, Zhijian | Zhang, Jingping | Wu, Yunchao | Zhao, Chunyu | Liu, Songlin | Zhou, Changhao | Huang, Xiaoping
Nutrient and heavy metal (Fe, Mn, Ni, Cu, Pb, Zn, Cr, Cd and As) concentrations in porewater in sediment cores and their diffusive benthic fluxes were investigated in Daya Bay, South China, to study the accumulation and transfer of nutrients/metals at the sediment-water interface, and to discuss the impact of human activities on nutrients/metals. Nutrients and heavy metals displayed different profiles in porewater, which was mainly attributed to the distinct biogeochemical conditions in sediments. Total mean fluxes of nutrients (except NO3 and NO2) and metals in study area were positive, indicating nutrients and metals diffused from the sediment to overlying water, and sediment was generally the source of nutrients/metals. Human activities and the weak hydrodynamic force made nutrients/metals accumulate in sediment, so the sediment should be paid more attention to as the endogenesis of contamination in Daya Bay waters.
显示更多 [+] 显示较少 [-]An estimation of the average residence times and onshore-offshore diffusivities of beached microplastics based on the population decay of tagged meso- and macrolitter 全文
2017
Hinata, Hirofumi | Mori, Keita | Ohno, Kazuki | Miyao, Yasuyuki | Kataoka, Tomoya
Residence times of microplastics were estimated based on the dependence of meso- and macrolitter residence times on their upward terminal velocities (UTVs) in the ocean obtained by one- and two-year mark-recapture experiments conducted on Wadahama Beach, Nii-jima Island, Japan. A significant linear relationship between the residence time and UTV was found in the velocity range of about 0.3–0.9ms−1, while there was no significant difference between the residence times obtained in the velocity range of about 0.9–1.4ms−1. This dependence on the UTV would reflect the uprush-backwash response of the target items to swash waves on the beach. By extrapolating the linear relationship down to the velocity range of microplastics, the residence times of microplastics and the 1D onshore-offshore diffusion coefficients were inferred, and are one to two orders of magnitude greater than the coefficients of the macroplastics.
显示更多 [+] 显示较少 [-]Near-surface distribution of pollutants in coastal waters as assessed by novel polyethylene passive samplers 全文
2017
Aminot, Yann | Belles, Angel | Alary, Claire | Readman, James W.
We report a novel and inexpensive method to provide high resolution vertical measurements of temporally integrated organic contaminants in surface and sub-surface waters in polluted coastal environments. It employs a strip of polyethylene deployed as a passive sampler. Verifications are confirmed via conventional spot sample analyses and against Performance Reference Compound (PRC) calibration methods. Analytes targeted include 16 Polycyclic Aromatic Hydrocarbons, 15 personal care products, 8 organophosphorus flame retardants, 4 antifouling ‘booster’ biocides and 15 n-alkanes. Whilst all contaminants typically revealed homogeneous concentrations from 10 cm to 3 m depth in the selected harbour (<30% variations), many increased sharply at the air-sea interface. The passive sampler was shown to afford better resolution than could be achieved using conventional analytical techniques at the surface microlayer (SML). Whilst hydrophobicity appeared to be a key factor for the enrichment of many determinants, less correlation was found for the emerging contaminants.
显示更多 [+] 显示较少 [-]Litter assessment on 99 Cuban beaches: A baseline to identify sources of pollution and impacts for tourism and recreation 全文
2017
Botero, C.M. | Anfuso, G. | Milanes, C. | Cabrera, A. | Casas, G. | Pranzini, E. | Williams, A.T.
Litter presence was assessed on the entire Cuban coastline, and includes 99 beaches from all Cuban regions, during field work carried out in 2012 and 2015. A standard method verified in several countries was applied, which classified beaches for nine types of litter into four grades (A-excellent to D-poor). Almost half of the Cuban beaches obtained excellent cleanliness scores, although many needed to be better managed. In this baseline, the most common types of residue were general litter (8% grade D and 35% grades B/C) and potentially harmful litter (<68% with grade A). Resort beaches and those with international visitors showed the best litter management. Tourism Impacts seems to be related to visitor origin therefore choices to develop sustainable tourism in rural and village beaches (64%) appears low, if beach cleaning gross investment is focused on resort beaches (24%). Finally, this paper highlights geographical distribution and types of litter patterns.
显示更多 [+] 显示较少 [-]Spatial distribution of heavy hydrocarbons, PAHs and metals in polluted areas. The case of “Galicia”, Spain 全文
2017
Monaco, D. | Chianese, E. | Riccio, A. | Delgado-Sanchez, A. | Lacorte, S.
The aim of this work is to verify the impact of anthropogenic activities and the effects of accidental events, e.g. oil spills, on the marine environment. For this reason, marine sediments and soil samples were collected in the inner part of Vigo and Pontevedra bays, in the Galicia region, northwest Spain, an area interested by many events of oil spills and also characterized by coastal areas with intense anthropic activities; also Cíes Islands, a natural protected area facing the Vigo bay, was investigated, as background site. PAHs, heavy hydrocarbons and metals were analyzed according to standard methods, in order to satisfy quality assurance and quality check constraints. Total PAHs concentration (Σ₁₆ compounds) were in the range of 25–4000ng/g, and 30–800ng/g for marine sediments and soil samples, respectively. Even some samples from the Cíes Islands, show a contamination with values achieving >200ng/g of PAHs. Although contamination levels have been shown to be strong at several locations in the study area, their ranges are those typical of other estuarine sites, with PAHs and hydrocarbons primarily of pyrolytic origin. This observation was further confirmed by enrichment factors of some metals (Cd, Cu, Pb and Zn) that match to those of harbor and shipyard zones of the main industrial and commercial maritime areas.
显示更多 [+] 显示较少 [-]Trophic magnification of Dechlorane Plus in the marine food webs of Fildes Peninsula in Antarctica 全文
2017
Na, Guangshui | Yao, Yao | Gao, Hui | Li, Ruijing | Ge, Linke | Titaley, Ivan A. | Santiago-Delgado, Lisandra | Massey Simonich, Staci L.
The food web composition, assimilation efficiency of Dechlorane Plus (DP) in food web components, and even extrinsic conditions can affect the trophic biomagnification potentials of DP isomers in food webs. Antarctica ecological system is characterized by the presence of few consumers and simple trophic levels (TLs), which are crucial in discussing the behavior of contaminants. To assess the biomagnification potential of DP in the Antarctic food web, nine representative species were sampled and analyzed from the Fildes Peninsula. Results showed the DP concentrations ranged from 0.25ngg−1 to 6.81ngg−1 lipid weight in Antarctic biota and the concentrations of anti-DP and syn-DP showed significantly positive correlations with TLs (p<0.05, ra=0.85; rs=0.81, respectively), suggesting that syn-DP and anti-DP underwent biomagnification and the biomagnification ability of anti-DP was higher than that of syn-DP. The anti-DP fraction (anti-DP/∑DP) (ƒanti=0.23–0.53) of the organisms was lower than that of commercial products (ƒanti=0.68), demonstrating ƒanti was changed during long-range atmospheric transport or stereoselection enrichment through the food web. Furthermore, based on food web magnification factors (FWMF) comparison between DP and polychlorinated biphenyls (PCBs), the biomagnification potential of DP was found to be similar to that of highly chlorinated PCBs.
显示更多 [+] 显示较少 [-]Can environmental pollution by metals change genetic diversity? Ucides cordatus (Linnaeus, 1763) as a study case in Southeastern Brazilian mangroves 全文
2017
Banci, Karina Rodrigues da Silva | Mori, Gustavo Maruyama | Oliveira, Marcos Antonio de | Paganelli, Fernanda Laroza | Pereira, Mariana Rangel | Pinheiro, Marcelo Antonio Amaro
Industrial areas on estuarine systems are commonly affected by heavy metals, affecting all local biota. Random Amplified Polymorphic DNA (RAPD) was used to evaluate genetic diversity of Ucides cordatus at mangroves in southeastern Brazil (Juréia, J; São Vicente, SV; and Cubatão, C), with distinct pollution levels by metals. The genetic diversity of this species was compared with concentrations of metals (Cd, Pb, Cu, Cr and Hg) in the environment. A pollution gradient was confirmed (SV>C>J), with low levels detected in water, except for mercury in SV. All metals in the sediment samples were below Threshold Effect Level (TEL), without an apparent biological risk to the biota. Genetic distance was very similar between J and C, with SV occurring as an out-group. RAPD was a powerful tool to investigate the effect of metal pollution on genetic diversity of this mangrove crab, and to evaluate the conservation status of the mangrove ecosystem.
显示更多 [+] 显示较少 [-]Prevention through policy: Urban macroplastic leakages to the marine environment during extreme rainfall events 全文
2017
Axelsson, Charles | van Sebille, Erik
The leakage of large plastic litter (macroplastics) into the ocean is a major environmental problem. A significant fraction of this leakage originates from coastal cities, particularly during extreme rainfall events. As coastal cities continue to grow, finding ways to reduce this macroplastic leakage is extremely pertinent. Here, we explore why and how coastal cities can reduce macroplastic leakages during extreme rainfall events. Using nine global cities as a basis, we establish that while cities actively create policies that reduce plastic leakages, more needs to be done. Nonetheless, these policies are economically, socially and environmentally cobeneficial to the city environment. While the lack of political engagement and economic concerns limit these policies, lacking social motivation and engagement is the largest limitation towards implementing policy. We recommend cities to incentivize citizen and municipal engagement with responsible usage of plastics, cleaning the environment and preparing for future extreme rainfall events.
显示更多 [+] 显示较少 [-]Microplastic contamination of intertidal sediments of Scapa Flow, Orkney: A first assessment 全文
2017
Blumenröder, J. | Sechet, P. | Kakkonen, J.E. | Hartl, M.G.J.
The concentration of microplastic particles and fibres was determined in the intertidal sediments at selected sites in Scapa Flow, Orkney, using a super-saturated NaCl flotation technique to extract the plastic and FT-IR spectroscopy to determine the polymer types. Mean concentrations were 730 and 2300kg−1 sediment (DW), respectively. Detailed spatial and quantitative analysis revealed that their distribution was a function of proximity to populated areas and associated wastewater effluent, industrial installations, degree of shore exposure and complex tidal flow patterns. Sediment samples from Orkney showed similar levels of microplastic contamination as in two highly populate industrialized mainland UK areas, The Clyde and the Firth of Forth. It was concluded that relative remoteness and a comparative small island population are not predictors of lower microplastic pollution. Furthermore, a larger concerted effort across Scotland and the UK is required to establish a baseline microplastic database for the evaluation of future policy measures.
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