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Steroid markers to assess sewage and other sources of organic contaminants in surface sediments of Cienfuegos Bay, Cuba Texte intégral
2014
Tolosa, I. | Mesa, M. | Alonso-Hernandez, C.M.
Analyses of faecal steroids in coastal sediments from Cienfuegos Bay Cuba indicate chronic sewage contamination at the main outfalls from the city, where concentrations of coprostanol up to 5400ngg−1 (dry wt) were measured. In contrast, steroid concentrations and compositions from sites from the south part of the Bay are characteristic of uncontaminated sewage environments. The levels of coprostanol in the Cienfuegos sediments compares to the lower to mid-range of concentrations reported for coastal sediments on a world-wide basis, with sedimentary levels markedly below those previously reported for heavily impacted sites. This study delivers baseline data for further investigation of the effectiveness of the proposed sewerage plan promoted by the GEF project in Cienfuegos. Investigations on the correlations between faecal steroids and other organic contaminants confirmed that the major source of petroleum hydrocarbons within the bay was associated with the sewage effluents from the Cienfuegos city.
Afficher plus [+] Moins [-]Fishery gear interactions from stranded bottlenose dolphins, Florida manatees and sea turtles in Florida, U.S.A Texte intégral
2014
Documenting the extent of fishery gear interactions is critical to wildlife conservation efforts, especially for reducing entanglements and ingestion. This study summarizes fishery gear interactions involving common bottlenose dolphins (Tursiops truncatus truncatus), Florida manatees (Trichechus manatus latirostris) and sea turtles: loggerhead (Caretta caretta), green turtle (Chelonia mydas), leatherback (Dermochelys coriacea), hawksbill (Eretmochelys imbricata), Kemp’s ridley (Lepidochelys kempii), and olive ridley (Lepidochelys olivacea) stranding in Florida waters during 1997–2009. Fishery gear interactions for all species combined were 75.3% hook and line, 18.2% trap pot gear, 4.8% fishing nets, and 1.7% in multiple gears. Total reported fishery gear cases increased over time for dolphins (p<0.05), manatees (p<0.01), loggerheads (p<0.05) and green sea turtles (p<0.05). The proportion of net interaction strandings relative to total strandings for loggerhead sea turtles increased (p<0.05). Additionally, life stage and sex patterns were examined, fishery gear interaction hotspots were identified and generalized linear regression modeling was conducted.
Afficher plus [+] Moins [-]The distribution of dissolved lead in the coastal waters of the East China Sea Texte intégral
2014
The distribution of dissolved lead in the coastal waters of the East China Sea was investigated seasonally. The average concentrations in surface waters during the spring and autumn were 0.52nM and 0.27nM, respectively. In the spring, the concentration of dissolved Pb in the surface waters and bottom waters ranged from 0.13 to 1.86nM and from 0.15 to 0.94nM, respectively. For both the surface water and the bottom water, the highest values were observed at the Yangtze River Estuary. Seasonal variability of D-Pb between spring and autumn in the ECS was observed. These results suggested that riverine inputs and atmospheric inputs may be the main sources of lead in this area, while adsorption and co-precipitation on suspended particles at the river estuary and biological process may be the major sinks.
Afficher plus [+] Moins [-]Factors influencing variability of mercury input to the southern Baltic Sea Texte intégral
2014
Bełdowska, Magdalena | Saniewska, Dominika | Falkowska, Lucyna
The southern Baltic countries have been identified as significant sources of Hg into the sea. Are anthropogenic activities the sole source? How do meteorological parameters influence the deposition? Studies on input of Hg to the Baltic were conducted in 2008–2012 in the Polish coastal stations. The riverine load was found to depend directly or indirectly on the amount of precipitation and catchment type. Input of atmospheric Hg increased along with the number of precipitation episodes from remote maritime air masses, as well as with the number of days when continental air masses from regional (when domestic heating prevailed) and remote sources moved over the Baltic, during the heating season. During the non-heating season metal input was found to be proportional to episodes of rain from continental regional air masses and to the number of days under influence of continental and maritime air masses from regional sources.
Afficher plus [+] Moins [-]Out of sight, out of mind: Threats to the marine biodiversity of the Canary Islands (NE Atlantic Ocean) Texte intégral
2014
Riera, Rodrigo | Becerro, Mikel A. | Stuart-Smith, Rick D. | Delgado, Juan D. | Edgar, Graham J.
Out of sight, out of mind: Threats to the marine biodiversity of the Canary Islands (NE Atlantic Ocean) Texte intégral
2014
Riera, Rodrigo | Becerro, Mikel A. | Stuart-Smith, Rick D. | Delgado, Juan D. | Edgar, Graham J.
Lack of knowledge of the marine realm may bias our perception of the current status and threats to marine biodiversity. Less than 10% of all ecological literature is related to the ocean, and the information we have on marine species that are threatened or on the verge of extinction is scarce. This lack of information is particularly critical for isolated areas such as oceanic archipelagos. Here we review published and grey literature on the current status of marine organisms in the Canary Islands as a case description of the consequences that current out-of-sight out-of-mind attitudes may have on this unique environment. Global change, as represented by coastal development, pollution, exotic species and climate change, are currently affecting the distribution and abundance of Canarian marine organisms, and pose multiple threats to local species and communities. Environmental risks are significant at community and species levels, particularly for threatened species. Failure to address these trends will result in shifts in local biodiversity with important ecological, social, and economic consequences. Scientists, policy makers, educators, and relevant societal groups need to collaborate to reverse deleterious coastal biodiversity trends.
Afficher plus [+] Moins [-]Out of sight, out of mind: Threats to the marine biodiversity of the Canary Islands (NE Atlantic Ocean) Texte intégral
2014
Riera, Rodrigo | Becerro, Mikel | Stuart-Smith, Rick D. | Delgado, Juan D. | Edgar, Graham J.
Lack of knowledge of the marine realm may bias our perception of the current status and threats to marine biodiversity. Less than 10% of all ecological literature is related to the ocean, and the information we have on marine species that are threatened or on the verge of extinction is scarce. This lack of information is particularly critical for isolated areas such as oceanic archipelagos. Here we review published and grey literature on the current status of marine organisms in the Canary Islands as a case description of the consequences that current out-of-sight out-of-mind attitudes may have on this unique environment. Global change, as represented by coastal development, pollution, exotic species and climate change, are currently affecting the distribution and abundance of Canarian marine organisms, and pose multiple threats to local species and communities. Environmental risks are significant at community and species levels, particularly for threatened species. Failure to address these trends will result in shifts in local biodiversity with important ecological, social, and economic consequences. Scientists, policy makers, educators, and relevant societal groups need to collaborate to reverse deleterious coastal biodiversity trends. | We would like to thank Dr. Rogelio Herrera and Mr. Leopoldo Moro (Environment Agency of the Canarian Government) for their interchange of ideas and continuous encouragement throughout the manuscript. Thanks are due to the Center for Wildlife Recovery “La Tahonilla”, Cabildo de Tenerife, for supplying the data on turtles and cetaceans. | Peer Reviewed
Afficher plus [+] Moins [-]Impacts, recovery rates, and treatment options for spilled oil in marshes Texte intégral
2014
Michel, Jacqueline | Rutherford, Nicolle
In a review of the literature on impacts of spilled oil on marshes, 32 oil spills and field experiments were identified with sufficient data to generate recovery curves and identify influencing factors controlling the rate of recovery. For many spills, recovery occurred within 1–2 growing seasons, even in the absence of any treatment. Recovery was longest for spills with the following conditions: Cold climate; sheltered settings; thick oil on the marsh surface; light refined products with heavy loading; oils that formed persistent thick residues; and intensive treatment. Recovery was shortest for spills with the following conditions: Warm climate; light to heavy oiling of the vegetation only; medium crude oils; and less-intensive treatment. Recommendations are made for treatment based on the following oiling conditions: Free-floating oil on the water in the marsh; thicker oil (>0.5cm) on marsh surface; thinner oil (<0.5cm) on marsh surface; heavy oil loading on vegetation; and light to moderate oil loading on vegetation.
Afficher plus [+] Moins [-]Suspended sediment in tidal currents: An often-neglected pollutant that aggravates mangrove degradation Texte intégral
2014
Fu, Weiguo | Liu, Daomin | Yin, Qilin | Wu, Yanyou | Li, Pingping
In this study, the influence of sediments deposited on the leaves of different mangrove species due to tidal movements on photosynthetic characteristics and chlorophyll fluorescence of the species was explored. The degree of accelerated degradation among different mangrove species was also obtained. Results show that the leaves of mangrove species have varying degrees of sediment deposition. Sediment deposition leads to photosynthetic reduction and physiological stress among Kandelia candel, Aegiceras corniculatum, and Avicennia marina in the Quanzhou Bay. Thus, the deposition of suspended sediments from tidal currents is an important environmental factor that accelerates the degradation of some mangrove species.
Afficher plus [+] Moins [-]Environmental policy constraints for acidic exhaust gas scrubber discharges from ships Texte intégral
2014
Ülpre, H. | Eames, I.
Increasingly stringent environmental legislation on sulphur oxide emissions from the combustion of fossil fuels onboard ships (International Maritime Organization (IMO) Regulation 14) can be met by either refining the fuel to reduce sulphur content or by scrubbing the exhaust gases. Commonly used open loop marine scrubbers discharge warm acidic exhaust gas wash water into the sea, depressing its pH. The focus on this paper is on the physics and chemistry behind the disposal of acidic discharges in seawater.The IMO Marine Environment Protection Committee (MEPC 59/24/Add.1 Annex 9) requires the wash water to reach a pH greater than 6.5 at a distance of 4m from the point of discharge. We examine the engineering constraints, specifically size and number of ports, to identify the challenges of meeting regulatory compliance.
Afficher plus [+] Moins [-]Meiofauna and its sedimentary environment as an integrated indication of anthropogenic disturbance to sandy beach ecosystems Texte intégral
2014
Sun, Xinyu | Zhou, Hong | Hua, Er | Xu, Shuhui | Cong, Bingqing | Zhang, Zhinan
The accuracy and applicability of the Nematode/Copepod index (N/C) in monitoring the effects of environmental disturbances is controversial. In this study, we used an integrated approach that includes both meiofauna and the sedimentary environment to demonstrate a tourism-induced disturbance gradient among sampled beaches. We also analysed the relationships between meiofauna and environmental factors. The results showed that disturbed beaches were characterised by high values of meiofauna abundance, chlorophyll a content, total organic carbon content and N/C but lower levels of dissolved oxygen. The chlorophyll a and dissolved oxygen contents were found to be the most important factors for explaining the disturbance gradient amongst the beaches. The N/C index had a positive relationship with chlorophyll a and a negative relationship with dissolved oxygen. There was no significant relationship between N/C index and total organic carbon content.
Afficher plus [+] Moins [-]Source identification of heavy metal contamination using metal association and Pb isotopes in Ulsan Bay sediments, East Sea, Korea Texte intégral
2014
Chae, Jung Sun | Choi, Man Sik | Song, Yun Ho | Um, In Kwon | Kim, Jae Gon
To determine the characteristics of metal pollution sources in Ulsan Bay, East Sea, 39 surface and nine core sediments were collected within the bay and offshore area, and analyzed for metals and stable lead (Pb) isotopes.Most surface sediments (>95% from 48 sites) had high copper (Cu), zinc (Zn), cadmium (Cd), and Pb concentrations that were as much as 1.3 times higher than background values. The primary source of metal contamination came from activities related to nonferrous metal refineries near Onsan Harbor, and the next largest source was from shipbuilding companies located at the mouth of the Taehwa River. Three different anthropogenic sources and background sediments could be identified as end-members using Pb isotopes. Isotopic ratios for the anthropogenic Pb revealed that the sources were imported ores from Australia, Peru, and the United States. In addition, Pb isotopes of anthropogenic Pb discharged from Ulsan Bay toward offshore could be determined.
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