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Simulation of the potential effects of CO2 leakage from carbon capture and storage activities on the mobilization and speciation of metals Full text
2014
de Orte, Manoela Romanó | Sarmiento, Aguasanta M. | DelValls, T Ángel | Riba, Inmaculada
One of the main risks associated with carbon capture and storage (CCS) activities is the leakage of the stored CO2, which can result in several effects on the ecosystem. Laboratory-scale experiments were performed to provide data on the possible effects of CO2 leakage from CCS on the mobility of metals previously trapped in sediments. Metal-contaminated sediments were collected and submitted to acidification by means of CO2 injection using different pH treatments. The test lasted 10days, and samples were collected at the beginning and at the end of the experiment for metal analysis. The results revealed increases in the mobility of metals such as Co, Cu, Fe, Pb and Zn due to pH decreases. Geochemical modeling demonstrated that acidification influenced the speciation of the metals, increasing the concentrations of their free forms. These data suggest the possible sediment contamination consequences of accidental CO2 leakage during CCS activities.
Show more [+] Less [-]Analysis of floating debris behaviour in the Nakdong River basin of the southern Korean peninsula using satellite location tracking buoys Full text
2014
Jang, Seon Woong | Kim, Dae Hyun | Seong, Ki Taek | Chung, Yong Hyun | Yoon, Hong Joo
Most land-based debris enters the ocean via rivers during the rainy season. The Nakdong River system, the largest river entering the South Sea of Korea, discharges 3000tons of debris per year. We deployed small tracking buoys with satellite location transmitters to monitor river-borne floating debris movement. The buoys moved for various distances depending on the change in flux in different regions. A hot spot was expected to contain a large accumulation of floating debris. The central and lower parts of the eastern downstream region were identified as important regions. The results of this study provide information related to the movement of debris that can be used when establishing a method for collection of floating debris from rivers and streams. The study contributes to efforts to decrease the amount of floating debris in oceans and the costs associated with debris removal by improving the effectiveness of preventative measures.
Show more [+] Less [-]Screening of biosurfactant producers from petroleum hydrocarbon contaminated sources in cold marine environments Full text
2014
Cai, Qinhong | Zhang, Baiyu | Chen, Bing | Zhu, Zhiwen | Lin, Weiyun | Cao, Tong
An overview of literature about isolating biosurfactant producers from marine sources indicated no such producers have been reported form North Atlantic Canada. Water and sediment samples were taken from petroleum hydrocarbon contaminated coastal and offshore areas in this region. Either n-hexadecane or diesel was used as the sole carbon source for the screening. A modified colony-based oil drop collapsing test was used to cover sessile biosurfactant producers. Fifty-five biosurfactant producers belong to genera of Alcanivorax, Exiguobacterium, Halomonas, Rhodococcus, Bacillus, Acinetobacter, Pseudomonas, and Streptomyces were isolated. The first three genera were established after 1980s with interesting characteristics and limited relevant publications. Some of the 55 isolated strains were found with properties such as greatly reducing surface tension, stabilizing emulsion and producing flocculant. Isolates P6-4P and P1-5P were selected to demonstrate the performance of biosurfactant production, and were found to reduce the surface tension of water to as low as 28dynes/cm.
Show more [+] Less [-]Managing ocean information in the digital era – Events in Canada open questions about the role of marine science libraries Full text
2014
Wells, P. G.
Information is the foundation of evidence-based policies for effective marine environmental protection and conservation. In Canada, the cutback of marine science libraries introduces key questions about the role of such institutions and the management of ocean information in the digital age. How vital are such libraries in the mission of studying and protecting the oceans? What is the fate and value of the massive grey literature holdings, including archival materials, much of which is not in digital form but which often contains vital data? How important is this literature generally in the marine environmental sciences? Are we likely to forget the history of the marine pollution field if our digital focus eclipses the need for and access to comprehensive collections and skilled information specialists? This paper explores these and other questions against the backdrop of unprecedented changes in the federal libraries, marine environmental science and legislation in Canada.
Show more [+] Less [-]Historical records of organic pollutants in sediment cores Full text
2014
Bigus, Paulina | Tobiszewski, Marek | Namieśnik, Jacek
Analyses of sediment core samples are primary sources of historical pollution trends in aquatic systems. Determining organic compounds, such as POPs, in the dated sediments enables the estimation of their temporal concentration changes and the identification of the contaminant origin in local regions. Wars, large-scale fires, economical transitions, and bans on certain chemicals are reflected in the sediment organic compound concentrations. The high POP concentrations in surficial sediments suggest that these chemicals, even after being banned, remain in the environment. Furthermore, vertical profiles can help in understanding the sedimentation process and in estimating effective countermeasures against pollution. Moreover, studies published during the period 1991–2013 on PAHs, PCBs, OCPs, dioxins and dioxin-like compound concentrations in sediment core samples are reviewed.
Show more [+] Less [-]Potential impacts of historical disturbance on green turtle health in the unique & protected marine ecosystem of Palmyra Atoll (Central Pacific) Full text
2014
McFadden, Katherine W. | Gómez, Andrés | Sterling, Eleanor J. | Naro-Maciel, Eugenia
Palmyra Atoll, in the Central Pacific, is a unique marine ecosystem because of its remarkably intact food web and limited anthropogenic stressors. However during World War II the atoll was structurally reconfigured into a military installation and questions remain whether this may have impacted the health of the atoll’s ecosystems and species. To address the issue we assessed green sea turtle (n=157) health and exposure to contaminants at this foraging ground from 2008 to 2012. Physical exams were performed and blood was sampled for testosterone analysis, plasma biochemistry analysis, hematology and heavy metal exposure. Hematological and plasma chemistries were consistent with concentrations reported for healthy green turtles. Heavy metal screenings revealed low concentrations of most metals, except for high concentrations of iron and aluminum. Body condition indices showed that <1% of turtles had poor body condition. In this study, we provide the first published blood values for a markedly healthy sea turtle population at a remote Central Pacific Atoll.
Show more [+] Less [-]Marine wildlife entanglement: Assessing knowledge, attitudes, and relevant behaviour in the Australian community Full text
2014
Pearson, Elissa | Mellish, Sarah | Sanders, Ben | Litchfield, Carla
Marine debris remains a global challenge, with significant impacts on wildlife. Despite this, there is a paucity of research examining public understanding about marine wildlife entanglement [MWE], particularly within an Australian context. The present study surveyed two hundred and thirteen participants across three coastal sites to assess familiarity with MWE and the effectiveness of a new community education initiative ‘Seal the Loop’ [STL]. Results revealed attitudes toward marine wildlife were very positive (M 40.5, SD 4.12); however 32% of participants were unable to correctly explain what MWE is and risks to wildlife were under-estimated. STL may be one method to enhance public understanding and engagement-if community familiarity with the program can be increased. For those aware of STL (<13% of the sample at the time of the study), findings revealed this was having a positive impact (e.g. learning something new, changed waste disposal behaviours).
Show more [+] Less [-]Assessment of contamination, distribution and chemical speciation of trace metals in water column in the Dakar coast and the Saint Louis estuary from Senegal, West Africa Full text
2014
Diop, Cheikh | Dewaelé, Dorothée | Diop, Mamadou | Touré, Aminata | Cabral, Mathilde | Cazier, Fabrice | Fall, Mamadou | Diouf, Amadou | Ouddane, Baghdad
The water column from Dakar coast and Saint Louis estuary in Senegal, West Africa, was sampled in order to measure the contamination level by trace metals. The speciation of metals in water allowed performing a distribution between dissolved and particulate trace metals. For the dissolved metals, the metallic concentration and repartition between the organic fraction and the inorganic fraction were performed. The results show that the pollution of the estuary was more serious than in Dakar coast for Co, Cr, Ni, Pb and Zn; while, Cd and Cu were higher in Dakar coast. A strong affinity between metals and suspended particles has been revealed. Dissolved metals that have a tendency to form organic metal complexes are in decreasing order: Cd, Zn, Pb, Co=Cr=Mn, Cu and Ni. The results showed that the mobility of trace metals in estuary is controlled by dissolved organic carbon, while in coast it depends on chlorides.
Show more [+] Less [-]Perfluoroalkyl and polyfluoroalkyl substances in sediments from South Bohai coastal watersheds, China Full text
2014
Zhu, Zhaoyun | Wang, Tieyu | Wang, Pei | Lü, Yonglong | Giesy, John P.
This study investigated the concentrations and distribution of Perfluoroalkyl and polyfluoroalkyl substances (PFAS) in sediments of 12 rivers from South Bohai coastal watersheds. The highest concentrations of ΣPFAS (31.920ngg−1dw) and PFOA (29.021ngg−1dw) were found in sediments from the Xiaoqing River, which was indicative of local point sources in this region. As for other rivers, concentrations of ΣPFAS ranged from 0.218 to 1.583ngg−1dw were found in the coastal sediments and from 0.167 to 1.953ngg−1dw in the riverine sediments. Predominant PFAS from coastal and riverine areas were PFOA and PFBS, with percentages of 30% and 35%, respectively. Partitioning analysis showed the concentrations of PFNA, PFDA and PFHxS were significantly correlated with organic carbon. The results of a preliminary environmental hazard assessment showed that PFOS posed the highest hazard in the Mi River, while PFOA posed a relative higher hazard in the Xiaoqing River.
Show more [+] Less [-]Capacity for recovery of rocky subtidal assemblages following pollution abatement in a scenario of global change Full text
2014
Díez, I. | Santolaria, A. | Muguerza, N. | Gorostiaga, J.M.
The successful protection and management of marine ecosystems depend on understanding the capability of biota for recovering after stressor mitigation actions are taken. Here we present long-term changes (1984–2012) in degraded subtidal assemblages following the implementation of the sewerage scheme for the metropolitan area of Bilbao (1 million inhabitants). Qualitative and quantitative species composition of disturbed vegetation shifted over time, making it more similar to that of the reference assemblages considered. Species density in the disturbed habitats increased, which is also a positive sign of recovery. However, eleven years after the clean-up was completed, canopy-forming macrophytes showed no signs of recovery. We argue that the ecological resilience of the ecosystem may have been eroded after a long-standing pollution perturbation and that underlying climate change could be influencing the recovery trajectory of the degraded assemblages. The implications of these conclusions for the implementation of European marine environmental legislation are discussed.
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