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Isolation and characterization of a novel hydrocarbon-degrading bacterium Achromobacter sp. HZ01 from the crude oil-contaminated seawater at the Daya Bay, southern China Texte intégral
2014
Deng, Mao-Cheng | Li, Jing | Liang, Fu-Rui | Yi, Meisheng | Xu, Xiao-Ming | Yuan, Jian-Ping | Peng, Juan | Wu, Chou-Fei | Wang, Jiang-Hai
Microorganisms play an important role in the biodegradation of petroleum contaminants, which have attracted great concern due to their persistent toxicity and difficult biodegradation. In this paper, a novel hydrocarbon-degrading bacterium HZ01 was isolated from the crude oil-contaminated seawater at the Daya Bay, South China Sea, and identified as Achromobacter sp. Under the conditions of pH 7.0, NaCl 3% (w/v), temperature 28°C and rotary speed 150rpm, its degradability of the total n-alkanes reached up to 96.6% after 10days of incubation for the evaporated diesel oil. Furthermore, Achromobacter sp. HZ01 could effectively utilize polycyclic aromatic hydrocarbons (PAHs) as its sole carbon source, and could remove anthracene, phenanthrene and pyrence about 29.8%, 50.6% and 38.4% respectively after 30days of incubation. Therefore, Achromobacter sp. HZ01 may employed as an excellent degrader to develop one cost-effective and eco-friendly method for the bioremediation of marine environments polluted by crude oil.
Afficher plus [+] Moins [-]Ballast water: A threat to the Amazon Basin Texte intégral
2014
Pereira, Newton Narciso | Botter, Rui Carlos | Folena, Rafael Dompieri | Pereira, José Pinheiro Fragoso Neto | da Cunha, Alan Cavalcanti
Ballast water exchange (BWE) is the most efficient measure to control the invasion of exotic species from ships. This procedure is being used for merchant ships in national and international voyages. The ballast water (BW) salinity is the main parameter to evaluate the efficacy of the mid-ocean ballast water exchange. The vessels must report to the Port State Control (PSC), via ballast water report (BWR), where and how the mid-ocean BWE was performed. This measure allows the PSC to analyze this information before the ship arrives at the port, and to decide whether or not it should berth.Ship BW reporting forms were collected from the Captaincy of Santana and some ships were visited near the Port of Santana, located in Macapá (Amazon River), to evaluate the BW quality onboard. We evaluated data submitted in these BWR forms and concluded that the BWE efficacy might be compromised, because data contained in these BWR indicate that some ships did not change their BW. We found mistakes in filling the BWR forms and lack of information. Moreover, these ships had discharged BW with high level of salinity, Escherichia coli and total coliforms into the Amazon River. We concluded that the authorities of the Amazon Region need to develop more efficient proceedings to evaluate the ballast water reporting forms and BW quality, as there is potential risk of future invasion of exotic species in Brazilian ports.
Afficher plus [+] Moins [-]PM10 black carbon and ionic species concentration of urban atmosphere in Makassar of South Sulawesi Province, Indonesia Texte intégral
2014
Rashid, Mohd | Yunus, Sattar | Mat, Ramli | Baharun, Sabariah | Lestari, Puji
This paper presents a study on black carbon and ionic species concentrations in PM10, sampled from the urban area of Makassar in the Province of South Sulawesi, Indonesia. The samples were collected on a weekly basis within a period of one year from February 2012 to January 2013. Results showed that the mean concentration of PM10 black carbon was 2.01±0.93μg/m3, while ionic species concentrations were found in descending order; SO42−>NO3−>Cl−>NH4+, with mean concentrations of 1.44±1.04μg/m3, 1.11±1.06μg/m3, 0.87±0.91μg/m3, 0.49±0.64μg/m3, respectively. Black carbon concentration was higher during the dry months, which may be attributed to uncontrolled biomass burning during hot and dry weather conditions. Similarly, SO42− and NH4+ concentrations were higher during the dry month seasons. On the contrary, Cl− concentration was higher during the wet months, influenced by the marine environment surrounding the area.
Afficher plus [+] Moins [-]Managing ocean information in the digital era – Events in Canada open questions about the role of marine science libraries Texte intégral
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.
Afficher plus [+] Moins [-]Multiple stressors threatening the future of the Baltic Sea–Kattegat marine ecosystem: Implications for policy and management actions Texte intégral
2014
Jutterström, S. | Andersson, H.C. | Omstedt, A. | Malmaeus, J.M.
The paper discusses the combined effects of ocean acidification, eutrophication and climate change on the Baltic Sea and the implications for current management strategies. The scientific basis is built on results gathered in the BONUS+ projects Baltic-C and ECOSUPPORT. Model results indicate that the Baltic Sea is likely to be warmer, more hypoxic and more acidic in the future. At present management strategies are not taking into account temporal trends and potential ecosystem change due to warming and/or acidification, and therefore fulfilling the obligations specified within the Marine Strategy Framework Directive, OSPAR and HELCOM conventions and national environmental objectives may become significantly more difficult. The paper aims to provide a basis for a discussion on the effectiveness of current policy instruments and possible strategies for setting practical environmental objectives in a changing climate and with multiple stressors.
Afficher plus [+] Moins [-]Screening of biosurfactant producers from petroleum hydrocarbon contaminated sources in cold marine environments Texte intégral
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.
Afficher plus [+] Moins [-]Growth, nutrient status, and photosynthetic response to diesel-contaminated soil of a cordgrass, Spartina argentinensis Texte intégral
2014
Redondo-Gómez, Susana | Petenello, María C. | Feldman, Susana R.
The present study was conduced to investigate the tolerance limits of Spartina argentinensis, which occurs in inland marshes of the Chaco-Pampean regions of Argentina, to diesel-contaminated soil. A glasshouse experiment was designed to investigate the effect of diesel fuel from 0% to 3% on growth and photosynthetic apparatus of S. densiflora by measuring gas exchange and photosynthetic pigments. We also performed chemical analysis of plant samples, and determined mycorrhizal index. Tiller and root biomasses declined with increasing diesel fuel concentration, as well as photosynthetic rate (A). Reductions in A could be accounted for by non-stomatal limitations. Mycorrhizal roots of S. argentinensis were reduced by the presence of diesel fuel, but did not affect its nutritional status; in fact, most element concentrations increased with diesel contamination. Despite the negative effect of diesel-contaminated soil, S. argentinensis continued growing, which could be useful management options for phytorremediation of diesel-contaminated soils.
Afficher plus [+] Moins [-]Influence of urban runoff, inappropriate waste disposal practices and World War II on the heavy metal status of sediments in the southern half of Saipan Lagoon, Saipan, CNMI Texte intégral
2014
Denton, Gary R.W. | Emborski, Carmen A. | Habana, Nathan C. | Starmer, John A.
Heavy metals were examined in sediments from the southern half of Saipan Lagoon. These waters provided tactical access for US troops during WWII and were heavily shelled at the time. Mercury profiles in sediments were, to some extent, reflective of this event. Samples from the southern end of the lagoon, where an old post-war dumpsite once existed, were found to be substantially enriched with Pb, Cu and Zn. Further north, the lagoon was primarily impacted by urban runoff. Metal enrichment in sediments from this region was generally highest at storm drain outlets and attenuated seawards. Moderate enrichment was rarely exceeded for any element other than Hg beyond the 50m mark. Sediment quality guidelines used to flag potentially adverse ecological health effects revealed no PEL exceedances. TEL exceedances for Pb and Cu were identified in sediments near the former dumpsite. The public health implications of the data are briefly addressed.
Afficher plus [+] Moins [-]On the quantity and composition of floating plastic debris entering and leaving the Tamar Estuary, Southwest England Texte intégral
2014
Sadri, Saeed S. | Thompson, Richard C.
The majority of plastic debris found in the marine environment has land based sources and rivers are considered an important medium for transfer of this debris. Here we report on the quantity and composition of floating plastic debris collected from surface waters of the Tamar Estuary. This represents the first study of riverine transport of floating plastic debris into European waters during different tidal regimes. Plastics were found in a variety of forms and sizes and microplastics (<5mm) comprised 82% of the debris. The most abundant types of plastic were Polyethylene (40%), Polystyrene (25%) and Polypropylene (19%). There was a significant difference in size frequency distribution between the spring and neap tides with more fragments of larger size observed during spring tides. While it is clear that debris has accumulated on shorelines within the estuary, during our study this river did not identify as a net source or sink.
Afficher plus [+] Moins [-]Estimation of lost tourism revenue in Geoje Island from the 2011 marine debris pollution event in South Korea Texte intégral
2014
Jang, Yong Chang | Hong, Sunwook | Lee, Jongmyoung | Lee, Mi Jeong | Shim, Won Joon
Following a period of heavy rainfall in July 2011, a large amount of marine debris was washed up on the beaches of Geoje Island, South Korea, affecting the island’s tourism industry. The tourism revenue decreased due to this pollution event and was estimated by multiplying the decreased number of visitors by the average expenditure of visitors to the beaches. Due to the fact that the visitor count at the Island’s beaches decreased from 890,435 in 2010 to 330,207 in 2011 (i.e., a reduction of 560,228 persons, 63%), the tourism revenue loss of the island was estimated to be US$29 – 37 million. This study is one of the few to consider the economic effects of marine debris.
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