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Potential impacts of historical disturbance on green turtle health in the unique & protected marine ecosystem of Palmyra Atoll (Central Pacific)
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.
显示更多 [+] 显示较少 [-]Marine wildlife entanglement: Assessing knowledge, attitudes, and relevant behaviour in the Australian community
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).
显示更多 [+] 显示较少 [-]Estimation of lost tourism revenue in Geoje Island from the 2011 marine debris pollution event in South Korea
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.
显示更多 [+] 显示较少 [-]Assessment of heavy metal impact on sediment quality of the Xiaoqinghe estuary in the coastal Laizhou Bay, Bohai Sea: Inconsistency between two commonly used criteria
2014
Zhuang, Wen | Gao, Xuelu
Surface sediments in the Xiaoqinghe estuary, southwestern coastal Laizhou Bay, were examined to assess the bio-toxic risk of heavy metals (Cd, Cu, Ni, Pb and Zn) with the effects range-low and effects range-median guidelines (ERL–ERMs) and the concentration ratio of simultaneously extractable metals to acid volatile sulfides ([SEM]/[AVS]). Based on the ERL–ERM guidelines, bio-toxic effect caused by Cu, Ni, Pb and Zn could be expected in the riverine surface sediments of the Xiaoqinghe estuary; and the surface sediments in the marine area were in good quality and only Ni might cause bio-toxic effect occasionally. The AVS–SEM guidelines revealed that no bio-toxic effect could be caused by any of the studied metals in both the riverine and marine sediments, since there were excess sulfides in surface sediments which could form water-insoluble substances with free metal ions and reduce the bioavailability of heavy metals.
显示更多 [+] 显示较少 [-]Assessment of susceptibility to pollution in littoral waters using the concept of recovery time
2014
Gómez, Aina G. | Juanes, J. A. (José A.) | Ondiviela, Bárbara | Revilla, José A.
Susceptibility to pollution can be related to the flushing capacity of aquatic systems. Transport time scales constitute a useful tool for representing the water exchange and transport processes. A new transport time scale, recovery time, and a methodology to estimate it by means of numerical models is hereby developed. Recovery time, calculated in Gijon, Santander and Tarragona harbours, is significantly related to physical, chemical and biological water quality indicators. Susceptibility, assessed through recovery time values, provides spatial patterns of expected flushing capacity, being sensitive to physical and hydrodynamic characteristics. The developed method is appropriate to estimate recovery time and assess susceptibility against pollution in littoral waters having great potential to be applied to different disciplines. Recovery time could be used in littoral waters as a surrogate of water quality indicators, to establish efficient monitoring programs, to define and characterize modified water bodies or to improve the design of marine infrastructures.
显示更多 [+] 显示较少 [-]Cryptosporidium and Giardia in tropical recreational marine waters contaminated with domestic sewage: Estimation of bathing-associated disease risks
2014
Betancourt, Walter Q. | Duarte, Diana C. | Vásquez, Rosa C. | Gurian, Patrick L.
Sewage is a major contributor to pollution problems involving human pathogens in tropical coastal areas. This study investigated the occurrence of intestinal protozoan parasites (Giardia and Cryptosporidium) in tropical recreational marine waters contaminated with sewage. The potential risks of Cryptosporidium and Giardia infection from recreational water exposure were estimated from the levels of viable (oo) cysts (DIC+, DAPI+, PI−) found in near-shore swimming areas using an exponential dose response model. A Monte Carlo uncertainty analysis was performed in order to determine the probability distribution of risks. Microbial indicators of recreational water quality (enterococci, Clostridium perfringens) and genetic markers of sewage pollution (human-specific Bacteroidales marker [HF183] and Clostridium coccoides) were simultaneously evaluated in order to estimate the extent of water quality deterioration associated with human wastes. The study revealed the potential risk of parasite infections via primary contact with tropical marine waters contaminated with sewage; higher risk estimates for Giardia than for Cryptosporidium were found. Mean risks estimated by Monte Carlo were below the U.S. EPA upper bound on recreational risk of 0.036 for cryptosporidiosis and giardiasis for both children and adults. However, 95th percentile estimates for giardiasis for children exceeded the 0.036 level. Environmental surveillance of microbial pathogens is crucial in order to control and eradicate the effects that increasing anthropogenic impacts have on marine ecosystems and human health.
显示更多 [+] 显示较少 [-]Regulation of solid waste management at Brazilian ports: Analysis and proposals for Brazil in light of the European experience
2014
Jaccoud, Cristiane | Magrini, Alessandra
With a coastline of 8500km, Brazil has 34 public ports and various private terminals, which together in 2012 handled 809 million tonnes of goods. The solid wastes produced (from port activities, ships and cargoes) pose a highly relevant problem, both due to the quantity and diversity, requiring a complex and integrated set of practices resulting from legal requirements and proactive initiatives. The main Brazilian law on solid waste management is recent (Law 12,305/2010) and the specific rules on solid waste in ports are badly in need of revision to meet the challenges caused by expansion of the sector and to harmonize them with the best global practices. This paper analyzes the current legal/regulatory framework for solid waste management at Brazilian ports and compares this structure with the practice in Europe. At the end, we suggest initiatives to improve the regulation of solid wastes at Brazilian ports.
显示更多 [+] 显示较少 [-]PAH concentrations in Coquina (Donax spp.) on a sandy beach shoreline impacted by a marine oil spill
2014
Snyder, Richard A. | Vestal, Alexandra | Welch, Christina | Barnes, Gracie | Pelot, Robert | Ederington-Hagy, Melissa | Hileman, Fredrick
The BP MC252 well failure in the Gulf of Mexico, April 2010 caused concern for crude oil and polycyclic aromatic hydrocarbon (PAHs) exposure along the sandy beaches of the Florida Panhandle. We began collections of Coquina clams (Donax spp.) from the surf zone of Florida Panhandle beaches to monitor PAH contamination to compliment analysis of surf zone sand samples. These clams had higher levels of PAHs relative to ambient sand, and this allowed us to continue to monitor PAH levels after sand concentrations fell below limits of detection. PAH levels in the Coquina tissues were highly variable, perhaps indicative of the heterogeneous distribution of oil and tar on the beaches and exposure to tar particles. Overall, PAH levels decreased continuously in both sand and Coquina tissues, reaching limits of detection within one and two years respectively after oil landed on Florida Panhandle beaches. Our work suggests these surf zone molluscs may be used to monitor pollutant exposure along high energy sandy beach shorelines.
显示更多 [+] 显示较少 [-]The Mussel Watch California pilot study on contaminants of emerging concern (CECs): Synthesis and next steps
2014
Maruya, Keith A. | Dodder, Nathan G. | Weisberg, Stephen B. | Gregorio, Dominic | Bishop, Jonathan S. | Klosterhaus, Susan | Alvarez, David A. | Furlong, Edward T. | Bricker, Suzanne | Kimbrough, Kimani L. | Lauenstein, Gunnar G.
A multiagency pilot study on mussels (Mytilus spp.) collected at 68 stations in California revealed that 98% of targeted contaminants of emerging concern (CECs) were infrequently detectable at concentrations ⩽1ng/g. Selected chemicals found in commercial and consumer products were more frequently detected at mean concentrations up to 470ng/g dry wt. The number of CECs detected and their concentrations were greatest for stations categorized as urban or influenced by storm water discharge. Exposure to a broader suite of CECs was also characterized by passive sampling devices (PSDs), with estimated water concentrations of hydrophobic compounds correlated with Mytilus concentrations. The results underscore the need for focused CEC monitoring in coastal ecosystems and suggest that PSDs are complementary to bivalves in assessing water quality. Moreover, the partnership established among participating agencies led to increased spatial coverage, an expanded list of analytes and a more efficient use of available resources.
显示更多 [+] 显示较少 [-]Surface weathering and dispersibility of MC252 crude oil
2014
Daling, Per S. | Leirvik, Frode | Almås, Inger Kjersti | Brandvik, Per Johan | Hansen, Bjørn Henrik | Lewis, Alun | Reed, Mark
Results from a comprehensive oil weathering and dispersant effectiveness study of the MC252 crude oil have been used to predict changes in oil properties due to weathering on the sea surface and to estimate the effective “time window” for dispersant application under various sea conditions. MC252 oil is a light paraffinic crude oil, for which approximately 55wt.% will evaporate within 3–5days when drifting on the sea. An unstable and low-viscosity water-in-oil (w/o) emulsion are formed during the first few days at the sea surface. This allows a high degree of natural dispersion when exposed to breaking wave conditions. Under calm sea conditions, a more stable and light-brown/orange colored water-in-oil (w/o) emulsion may start to form after several days, and viscosities of 10,000–15,000mPas can be achieved after 1–2weeks. The “time window” for effective use of dispersants was estimated to be more than 1week weathering at sea.
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