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What did we learn from PEGASEAS forum “Science and Governance of the Channel Marine Ecosystem”?
2015
Evariste, Emmanuelle | Claquin, Pascal | Robin, Jean-Paul | Auber, Arnaud | McQuatters-Gollop, Abigail | Fletcher, Stephen | Glegg, Gillian | Dauvin, Jean-Claude
As one of the busiest marine ecosystems in the world, the English Channel is subjected to strong pressures due to the human activities occurring within it. Effective governance is required to improve the combined management of different activities and so secure the benefits provided by the Channel ecosystem. In July 2014, a Cross-Channel Forum, entitled “Science and Governance of the Channel Marine Ecosystem”, was held in Caen (France) as part of the INTERREG project “Promoting Effective Governance of the Channel Ecosystem” (PEGASEAS). Here we use outputs from the Forum as a framework for providing Channel-specific advice and recommendations on marine governance themes, including the identification of knowledge gaps, which may form the foundation of future projects for the next INTERREG project call (2015–2020).
Afficher plus [+] Moins [-]Renewables-to-reefs? – Decommissioning options for the offshore wind power industry
2015
Smyth, K. (Katie) | Christie, Nikki | Burdon, Daryl | Atkins, Jonathan P. | Barnes, Richard | Elliott, Michael
The offshore wind power industry is relatively new but increasing globally, hence it is important that the whole life-cycle is managed. The construction–operation–decommissioning cycle is likely to take 20–30years and whilst decommissioning may not be undertaken for many years, its management needs to be addressed in both current and future marine management regimes. This can be defined within a Drivers–Activities–Pressures–State Changes–Impacts (on human Welfare)–Responses framework. This paper considers the main decommissioning options – partial or complete removal of all components. A SWOT analysis shows environmental and economic benefits in partial as opposed to complete removal, especially if habitat created on the structures has conservation or commercial value. Benefits (and repercussions) are defined in terms of losses and gains of ecosystem services and societal benefits. The legal precedents and repercussions of both options are considered in terms of the 10-tenets of sustainable marine management. Finally a ‘renewables-to-reefs’ programme is proposed.
Afficher plus [+] Moins [-]Heavy metal levels in dune sands from Matanzas urban resorts and Varadero beach (Cuba): Assessment of contamination and ecological risks
2015
Díaz Rizo, Oscar | Buzón González, Fran | Arado López, Juana O. | Denis Alpízar, Otoniel
Concentrations of chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn) and lead (Pb) in dune sands from six urban and suburban Matanzas (Cuba) resorts and Varadero beach were estimated by X-ray fluorescence analysis. Ranges of metal contents in dune sands show a strong variation across the studied locations (in mg/kg−1): 20–2964 for Cr, 17–183 for Ni, 17–51 for Cu, 18–88 for Zn and 5–29 for Pb. The values of contamination factors and contamination degrees how that two of the studied Matanzas's resorts (Judio and Chirry) are strongly polluted. The comparison with Sediment Quality Guidelines shows that dune sands from Judio resort represent a serious risk for humans, due to polluted Cr and Ni levels, while sands from the rest of the studied resorts, including Varadero beach, do not represent any risk for public use.
Afficher plus [+] Moins [-]Experimental study of particulate products for aging of 1,3,5–trimethylbenzene secondary organic aerosol
2015
Huang, Mingqiang | Lin, Yuehong | Huang, Xianying | Liu, Xingqiang | Guo, Xiaoyong | Hu, Changjin | Zhao, Weixiong | Gu, Xuejun | Fang, Li | Zhang, Weijun
Secondary organic aerosol (SOA) from the photooxidation of aromatic compounds is a very complex mixture containing products with a different chemical nature that are dependent on aging processes. In this study, we focus on the chemical characterization of major products that are formed from the OH–initiated oxidation of 1,3,5–trimethylbenzene and subsequent aging through OH–initiated reactions in the presence of NOx.The chemical composition of aged particles were measured in real–time by an aerosol laser time of flight mass spectrometer (ALTOFMS) coupled with Fuzzy C–Means (FCM) clustering algorithm. Experimental results demonstrated that methyl glyoxylic acid, 2–methyl–4–oxo–2–pentenoic acid, 3,5–dimethylbenzoic acid, 2–methyl–2,3–dihydroxyl–4–oxo–pentanoic acid, dimethyl–nitrophenol, 3,4–dimethyl–2–hydroxy–3–oxo–pentandioic acid, 2,4–dimethyl–2,3–dihydroxy–6–oxo–4–heptenoic acid, 2,4–dimethyl–4–hydroxy–2,3–epoxy– heptylic acid, 2,4–dimethyl–2,3,4–trihydroxy–5,6–dioxo–heptylic acid, and oligomer components were the predominant products in the aging particles. The possible reaction mechanisms leading to these aged products were also discussed and proposed.
Afficher plus [+] Moins [-]Adaptability of free-floating green tide algae in the Yellow Sea to variable temperature and light intensity
2015
Cui, Jianjun | Zhang, Jianheng | Huo, Yuanzi | Zhou, Lingjie | Wu, Qing | Chen, Liping | Yu, Kefeng | He, Peimin
In this study, the influence of temperature and light intensity on the growth of seedlings and adults of four species of green tide algae (Ulva prolifera, Ulva compressa, Ulva flexuosa and Ulva linza) from the Yellow Sea was evaluated. The results indicated that the specific growth rate (SGR) of seedlings was much higher than that of adults for the four species. The adaptability of U. prolifera is much wider: Adult daily SGRs were the highest among the four species at 15–20°C with 10–600μmol·m−2·s−1 and 25–30°C with 200–600μmol·m−2·s−1. SGRs were 1.5–3.5 times greater than the other three species at 15–25°C with 200–600μmol·m−2·s−1. These results indicate that U. prolifera has better tolerance to high temperature and light intensity than the other three species, which may in part explain why only U. prolifera undergoes large-scale outbreaks and floats to the Qingdao coast while the other three species decline and disappear at the early stage of blooming.
Afficher plus [+] Moins [-]The Marine Strategy Framework Directive and the ecosystem-based approach – pitfalls and solutions
2015
Berg, Torsten | Fürhaupter, Karin | Teixeira, Heliana | Uusitalo, Laura | Zampoukas, Nikolaos
The European Marine Strategy Framework Directive aims at good environmental status (GES) in marine waters, following an ecosystem-based approach, focused on 11 descriptors related to ecosystem features, human drivers and pressures. Furthermore, 29 subordinate criteria and 56 attributes are detailed in an EU Commission Decision. The analysis of the Decision and the associated operational indicators revealed ambiguity in the use of terms, such as indicator, impact and habitat and considerable overlap of indicators assigned to various descriptors and criteria. We suggest re-arrangement and elimination of redundant criteria and attributes avoiding double counting in the subsequent indicator synthesis, a clear distinction between pressure and state descriptors and addition of criteria on ecosystem services and functioning. Moreover, we suggest the precautionary principle should be followed for the management of pressures and an evidence-based approach for monitoring state as well as reaching and maintaining GES.
Afficher plus [+] Moins [-]Variations in the abundance and structural diversity of microbes forming biofilms in a thermally stressed coral reef system
2015
Mahmoud, Huda
Little information is known about biofilm formation in the thermally stressed coral reef systems north of the Arabian Gulf. The current study investigates the abundance and diversity of marine microbes involved in biofilm formation and their succession over a period of 14weeks (May–August 2007) at temperatures exceeding 32°C. The results showed variations in microbial numbers and the development of more stable biofilm communities as the biofilms aged. The culture-dependent technique and microscopic examination of the developed biofilms showed the dominance of key species known for their role in precipitating CaCO3 such as Vibrio and in facilitating coral larvae settlement and metamorphosis such as Pseudoalteromonas, Bacillariophyceae and Rhodophyceae. The results revealed biofilm formations with microbial diversities that have the potential to support the larval settlement and metamorphism of marine organisms and to consolidate and stabilize biofilms via the process of calcification in the thermally stressed coral reef system considered herein.
Afficher plus [+] Moins [-]Distributions, sources and ecological risk assessment of arsenic and mercury in the surface sediments of the southwestern coastal Laizhou Bay, Bohai Sea
2015
Zhuang, Wen | Gao, Xuelu
The spatial distributions of As and Hg in riverine and marine surface sediments of the coastal southwestern Laizhou Bay were obtained, and multiple indices and guidelines were applied to assess their contamination and ecological risks. The As concentrations in riverine sediments were close to those in marine sediments, and on the whole the dominant proportion of As was identified to be from natural sources. The Hg concentrations in riverine sediments were much higher than those in marine sediments, so river transportation was likely the main way of Hg into the southwestern Laizhou Bay. In respect of As, the sediment quality was fine according to the risk assessment methods used; in contrast, Hg presented an extremely contaminated status with a very high ecological risk in some riverine sediments, while most of the marine sediments were relatively much less polluted by Hg and under a lower ecological risk from it.
Afficher plus [+] Moins [-]Physiological perturbations in juvenile cuttlefish Sepia officinalis induced by subchronic exposure to dissolved zinc
2015
Le Pabic, Charles | Caplat, Christelle | Lehodey, Jean-Paul | Dallas, Lorna | Koueta, N. (Noussithé)
Although cephalopod early life stage development often occurs in coastal areas where contamination is real and continuous, the physiological perturbations induced by contaminants have been rarely investigated. This study focused on the Zn as it is one of the trace metals the most concentrated in coastal waters, worldwide. As Zn-tolerance limits were unknown in juvenile Sepia officinalis, the aim of this study was to estimate the threshold inducing mortality during the 2-first weeks post-hatching, and to determine its sensitivity using digestive and immune enzymatic assays, as well as growth and behavior follow-up during the first 5weeks post-hatching. Our study highlighted a Zn-mortality threshold lying between 185 and 230μgl−1, and growth reductions occurring after 5-week at 108μgl−1 and above, associated with enzymatic perturbations. These results underline a relatively important sensitivity of juvenile cuttlefish to Zn, pointed out by a wide diversity of biomarkers.
Afficher plus [+] Moins [-]δ13C and δ15N in deep-living fishes and shrimps after the Deepwater Horizon oil spill, Gulf of Mexico
2015
Quintana-Rizzo, Ester | Torres, Joseph J. | Ross, Steve W. | Romero, Isabel | Watson, Kathleen | Goddard, Ethan | Hollander, David
The blowout of the Deepwater Horizon (DWH) drill-rig produced a surface oil layer, dispersed micro-droplets throughout the water column, and sub-surface plumes. We measured stable carbon and nitrogen isotopes in mesopelagic fishes and shrimps in the vicinity of DWH collected prior to, six weeks after, and one year after the oil spill (2007, 2010 and 2011). In 2010, the year of the oil spill, a small but significant depletion of δ13C was found in two mesopelagic fishes (Gonostoma elongatum and Chauliodus sloani) and one shrimp (Systellaspis debilis); a significant δ15N enrichment was identified in the same shrimp and in three fish species (G. elongatum, Ceratoscopelus warmingii, and Lepidophanes guentheri). The δ15N change did not suggest a change of trophic level, but did indicate a change in diet. The data suggest that carbon from the Deepwater Horizon oil spill was incorporated into the mesopelagic food web of the Gulf of Mexico.
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