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Trophic structure in a pilot system for the integrated multi-trophic aquaculture off the east coast of Korean peninsula as determined by stable isotopes
2015
Park, Hyun Je | Han, Eunah | Lee, Won-Chan | Kwak, Jung Hyun | Kim, Hyung-Chul | Park, Mi Seon | Kang, Chang-Keun
To assess the potential for nutritional exploitation of caged-fish-derived waste through the use of extractive co-cultured species in a pilot system for an integrated multi-trophic aquaculture (IMTA), we compared their C and N stable isotope ratios with those of uncultured macroinvertebrates in and around the system. Black rockfish were co-cultured with sea cucumber, oyster, and two macroalgae as extractive species. Isotope signatures of the co-cultured sea cucumber at the IMTA site differed from those at the control site, indicating their assimilation of aquaculture wastes. In contrast, δ13C and δ15N of individual taxa of the cultured oyster and uncultured invertebrates were consistent between sites, suggesting a minor contribution of the aquaculture waste to benthic and pelagic food chains in and around the IMTA system. These results provide evidence of the suitability of using sea cucumber as an extractive species to reduce the impact of a monoculture system on the ambient environment.
Показать больше [+] Меньше [-]Soil Pollution Due to Irrigation with Arsenic-Contaminated Groundwater: Current State of Science
2015
Gillispie, Elizabeth C. | Sowers, Tyler D. | Duckworth, Owen W. | Polizzotto, Matthew L.
Food with elevated arsenic concentrations is becoming widely recognized as a global threat to human health. This review describes the current state of knowledge of soil pollution derived from irrigation with arsenic-contaminated groundwater, highlighting processes controlling arsenic cycling in soils and resulting arsenic impacts on crop and human health. Irrigation practices utilized for both flooded and upland crops have the potential to load arsenic to soils, with a host of environmental and anthropogenic factors ultimately determining the fate of arsenic. Continual use of contaminated groundwater for irrigation may result in soils with concentrations sufficient to create dangerous arsenic concentrations in the edible portions of crops. Recent advances in low-cost water and soil management options show promise for mitigating arsenic impacts of polluted soils. Better understanding of arsenic transfer from soil to crops and the controls on long-term soil arsenic accumulation is needed to establish effective arsenic mitigation strategies within vulnerable agronomic systems.
Показать больше [+] Меньше [-]Integrating science education and marine conservation through collaborative partnerships
2015
Martin, Jeannie Miller | Higgins, Katie | Lee, Kristin | Stearns, Kira | Hunt, Lori
The Georgia Sea Turtle Center has a mission of conservation based rehabilitation, research, and education. Marine debris is a serious threat to marine species. In an effort to educate local students, the GSTC obtained a grant to provide educational opportunities to local third graders. Third and fourth grade classes in Glynn County, Georgia were offered a Garbage in the Water program and 964 students were reached. After programming, students showed a statistically significant (p<.0001) increase in test scores between the pre and posttests. This success led to repeat funding for additional programming for first grades as well as a formalized relationship with the Glynn County School District. As part of this relationship the Georgia Sea Turtle Center is now the official field trip location for all third grades in the district.
Показать больше [+] Меньше [-]Temporal variations of heavy metals levels in Perna viridis, on the Chacopata-Bocaripo lagoon axis, Sucre State, Venezuela
2015
Pinto, Rafael | Acosta, Vanessa | Segnini, Mary Isabel | Brito, Leonor | Martínez, Gregorio
Perna viridis was used as biomonitor to assess heavy metal levels in the Chacopata-Bocaripo lagoon axis, Venezuela, during rain and drought seasons. The mussels were weighed and measured. The metal concentrations were determined by atomic absorption spectrophotometry. For rain period, the order of bioavailability was: Cu>Ni>Mn>Co>Cd>Pb, and for drought: Cu>Mn>Ni>Co>Pb>Cd. The concentrations of Ni, Co, Cd and Pb showed significant differences (P<0.05) in both periods. There was higher metal accumulation during drought season, possibly related to upwelling, since it produces an increase in primary productivity, which translates more food into organisms, making metals bioavailable for mussels. Only Cu and Mn showed significant relationships between the size and metal concentration, during drought period, it may be because of the organisms need for these essential metals in different physiological processes.
Показать больше [+] Меньше [-]Ex-situ evaluation of bauxite residues as amendment for trace elements stabilization in dredged sediment from Mediterranean Sea: A case study
2015
Taneez, Mehwish | Hurel, Charlotte | Marmier, Nicolas
Stabilization of marine dredged sediments contaminated with multi-elements is a challenging task in choosing the appropriate sorbent and application dosage. The present study investigates the possibility of using bauxite residues (Bauxaline® and Bauxsol) as amendment for the treatment of contaminated sediment. A pilot scale experiment was conducted for three months to stabilize trace elements in composted contaminated sediment sample using 5% by-product amendment. The results showed that after 3months of treatment, cationic trace elements were effectively immobilized but increased leaching of anionic pollutants was observed. Increased leaching of anionic pollutants could be limited by addition of higher quantities of amendments. The total content of available pollutants decreased in stabilized sediments but this treatment has no effect on the classification of waste. The leachates were then evaluated for acute toxicity using estuarine rotifers Brachionus plicatilis. Bauxite residues can be inexpensive choices for the stabilization of cationic pollutants in dredged sediments.
Показать больше [+] Меньше [-]Bioremediation of diesel from a rocky shoreline in an arid tropical climate
2015
Guerin, Turlough F.
A non invasive sampling and remediation strategy was developed and implemented at shoreline contaminated with spilt diesel. To treat the contamination, in a practical, cost-effective, and safe manner (to personnel working on the stockpiles and their ship loading activity), a non-invasive sampling and remediation strategy was designed and implemented since the location and nature of the impacted geology (rock fill) and sediment, precluded conventional ex-situ and any in-situ treatment where drilling is required. A bioremediation process using surfactant, and added N & P and increased aeration, increased the degradation rate allowing the site owner to meet their regulatory obligations. Petroleum hydrocarbons decreased from saturation concentrations to less than detectable amounts at the completion of treatment.
Показать больше [+] Меньше [-]Relative bioavailability and toxicity of fuel oils leaking from World War II shipwrecks
2015
Faksness, Liv-Guri | Daling, Per | Altin, Dag | Dolva, Hilde | Fosbæk, Bjørn | Bergstrøm, Rune
The Norwegian Authorities have classified 30 WWII shipwrecks to have a considerable potential for pollution to the environment, based on the location and condition of the wreck and the types and amount of fuel. Oil thus far has been removed from eight of these shipwrecks. The water accommodated fractions of oils from two British wrecks and two German wrecks have been studied with special emphasis on chemistry and biological effects (algae growth (Skeletonema costatum) and copepod mortality (Calanus finmarchicus)). Chemical analyses were also performed on three additional German wreck oils. The results from these studies show that the coal based oils from German WWII shipwrecks have higher toxicity to marine organisms than the mineral oils from the British shipwrecks. The potential for higher impact on the marine environment of coal based oils has resulted in an altering of the priority list for oil recovery from WWII wrecks by the authorities.
Показать больше [+] Меньше [-]Probabilistic ecological risk assessment of copper in Chinese offshore marine environments from 2005 to 2012
2015
Jin, Xiaowei | Liu, Fang | Wang, Yeyao | Zhang, Lingsong | Li, Zhao | Wang, Zijian | Giesy, John P. | Wang, Zhen
The objective of the present study was to conduct a probabilistic assessment of risk posed by copper found in the coastal marine environment of China from 2005 to 2012. This was achieved by applying a tiered ecological risk assessment (ERA) approach for characterization of risks of concentrations of copper from nationwide marine water monitoring program. The results show that from 2005 to 2012 the overall trend of hazard quotients (HQs) in the coastal marine environment of China the proportion of locations that exceed a HQ of 1.0 decreased from 64% in 2005 to 31% in 2012. While this indicates an overall improvement of the environment, there still have potential ecological risks in the most of the area, especially for the major gulfs of Liaodong and Bohai Bays and Yellow River Estuary. In addition, probabilities of exceeding the toxicity threshold for 5% of species were 27.6%, 5.4%, 4.9%, 0.8%, 0.4%, 1.0%, 1.8% and 0.12% annually between 2005 and 2012, respectively.
Показать больше [+] Меньше [-]Bayesian inference-based environmental decision support systems for oil spill response strategy selection
2015
Davies, Andrew J. | Hope, Max J.
Contingency plans are essential in guiding the response to marine oil spills. However, they are written before the pollution event occurs so must contain some degree of assumption and prediction and hence may be unsuitable for a real incident when it occurs. The use of Bayesian networks in ecology, environmental management, oil spill contingency planning and post-incident analysis is reviewed and analysed to establish their suitability for use as real-time environmental decision support systems during an oil spill response. It is demonstrated that Bayesian networks are appropriate for facilitating the re-assessment and re-validation of contingency plans following pollutant release, thus helping ensure that the optimum response strategy is adopted. This can minimise the possibility of sub-optimal response strategies causing additional environmental and socioeconomic damage beyond the original pollution event.
Показать больше [+] Меньше [-]Stable isotope variations in benthic primary producers along the Bosphorus (Turkey): A preliminary study
2015
Calizza, Edoardo | Aktan, Yelda | Costantini, Maria Letizia | Rossi, Loreto
The Bosphorus Strait is a dynamic and complex system. Recent evidences showed nitrogen and heavy metal concentrations to follow opposite patterns across the Strait, suggesting a complex spatial organisation of the anthropogenic disturbance in this system. Here, we provide isotopic information on the origin and transportation of dissolved nitrogen along the Bosphorus. C and N isotopic and elemental analyses were performed on specimens of Ulva lactuca and associated epiphytes sampled in five locations across the Strait. Variations in C and N isotopic signatures were observed in U. lactuca, pointing to a decrease in the availability of anthropogenic organic dissolved nitrogen along a north-south direction. Conversely, epiphytes did not show isotopic or elemental patterns across the Strait. These results suggest that preliminary stable isotope surveys in extended costal systems basing on U. lactuca can represent a valuable tool to focus meaningful targets and hypotheses for pollution studies in the Mediterranean region.
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