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Distribution and assessment of marine debris in the deep Tyrrhenian Sea (NW Mediterranean Sea, Italy) Full text
2015
Angiolillo, Michela | Lorenzo, Bianca di | Farcomeni, Alessio | Bo, Marzia | Bavestrello, Giorgio | Santangelo, Giovanni | Cau, Angelo | Mastascusa, Vincenza | Cau, Alessandro | Sacco, Flavio | Canese, Simonepietro
Marine debris is a recognized global ecological concern. Little is known about the extent of the problem in the Mediterranean Sea regarding litter distribution and its influence on deep rocky habitats. A quantitative assessment of debris present in the deep seafloor (30–300m depth) was carried out in 26 areas off the coast of three Italian regions in the Tyrrhenian Sea, using a Remotely Operated Vehicle (ROV). The dominant type of debris (89%) was represented by fishing gears, mainly lines, while plastic objects were recorded only occasionally. Abundant quantities of gears were found on rocky banks in Sicily and Campania (0.09–0.12 debris m−2), proving intense fishing activity. Fifty-four percent of the recorded debris directly impacted benthic organisms, primarily gorgonians, followed by black corals and sponges. This work provides a first insight on the impact of marine debris in Mediterranean deep ecosystems and a valuable baseline for future comparisons.
Show more [+] Less [-]A drifter for measuring water turbidity in rivers and coastal oceans Full text
2015
Marchant, Ross | Reading, Dean | Ridd, James | Campbell, Sean | Ridd, Peter
A disposable instrument for measuring water turbidity in rivers and coastal oceans is described. It transmits turbidity measurements and position data via a satellite uplink to a processing server. The primary purpose of the instrument is to help document changes in sediment runoff from river catchments in North Queensland, Australia. The ‘river drifter’ is released into a flooded river and drifts downstream to the ocean, measuring turbidity at regular intervals. Deployment in the Herbert River showed a downstream increase in turbidity, and thus suspended sediment concentration, while for the Johnstone River there was a rapid reduction in turbidity where the river entered the sea. Potential stranding along river banks is a limitation of the instrument. However, it has proved possible for drifters to routinely collect data along 80km of the Herbert River. One drifter deployed in the Fly River, Papua New Guinea, travelled almost 200km before stranding.
Show more [+] Less [-]Failure of the public health testing program for ballast water treatment systems Full text
2015
Cohen, Andrew N. | Dobbs, Fred C.
Since 2004, an international testing program has certified 53 shipboard treatment systems as meeting ballast water discharge standards, including limits on certain microbes to prevent the spread of human pathogens. We determined how frequently certification tests failed a minimum requirement for a meaningful evaluation, that the concentration of microbes in the untreated (control) discharge must exceed the regulatory limit for treated discharges. In 95% of cases where the result was accepted as evidence that the treatment system reduced microbes to below the regulatory limit, the discharge met the limit even without treatment. This shows that the certification program for ballast water treatment systems is dysfunctional in protecting human health. In nearly all cases, the treatment systems would have equally well “passed” these tests even if they had never been turned on. Protocols must require minimum concentrations of targeted microbes in test waters, reflecting the upper range of concentrations in waters where ships operate.
Show more [+] Less [-]Diving behaviour of wildlife impacted by an oil spill: A clean-up and rehabilitation success? Full text
2015
Chilvers, B.L. | Morgan, K.M. | Finlayson, G. | Sievwright, K.A.
The value of rehabilitating oiled wildlife is an on-going global debate. On October 5, 2011, the cargo vessel C/V Rena grounded on Astrolabe Reef, New Zealand (NZ), spilling over 300 tonnes of heavy fuel oil. As part of the Rena oil spill response, 383 little blue penguins (LBP, Eudyptula minor) were captured, cleaned, rehabilitated and released back into a cleaned environment. This research investigates foraging behaviour changes due either to the oil spill or by the rehabilitation process by comparing the diving behaviour of rehabilitated (n=8) and non-rehabilitated (n=6) LBPs and with LBP populations throughout NZ. Stabile isotope analysis of feathers was also used to investigate diet. There were no foraging behaviour differences between rehabilitated and non-rehabilitated LBPs and the overall diving behaviour of these LBPs have similar, if not less energetic, foraging behaviour than other LBPs in NZ. This suggests the rehabilitation process and clean-up undertaken after the Rena appears effective and helps justify the rehabilitation of oiled wildlife across the world.
Show more [+] Less [-]Elemental composition of two ecologically contrasting seamount fishes, the bluemouth (Helicolenus dactylopterus) and blackspot seabream (Pagellus bogaraveo) Full text
2015
Raimundo, Joana | Vale, Carlos | Martins, Inês | Fontes, Jorge | Graça, Gonçalo | Caetano, Miguel
Concentrations of V, Cr, Mn, Co, Ni, Cu, Zn, As, Se, Cd and Pb were determined in muscle, liver and gonads of two ecologically contrasting fishes, Helicolenus dactylopterus (benthic) and Pagellus bogaraveo (benthopelagic). Elevated concentrations of As, Se and Cd found in tissues of both species appear to mirror the contribution of volcanic activity to the natural inputs of elements to Azorean waters. Results showed different element accumulation between the two species. Whereas higher concentrations were found in the liver of P. bogaraveo, elevated values were observed in the muscle of H. dactylopterus. Differences in accumulation are most likely related to metabolic rates, diet specificities and habitat. Concentrations in gonads varied up to four orders of magnitude, being higher and more variable in P. bogaraveo than H. dactylopterus. Elevated values of Cd were detected in gonads of both species despite its non-essential role on metabolic functions, presumably related to elimination.
Show more [+] Less [-]Wildfires impact on surface nitrogen oxides and ozone in Central Italy Full text
2015
Di Carlo, Piero | Aruffo, Eleonora | Biancofiore, Fabio | Busilacchio, Marcella | Pitari, Giovanni | Dari-Salisburgo, Cesare | Tuccella, Paolo | Kajii, Yoshizumi
A summer campaign in Central Italy was carried out to study the impact of fire emissions on the mixing ratios of surface trace gases. Observations with a selective and sensitive instrument that uses the laser induced fluorescence technique for direct measurements of nitrogen dioxide (NO2), show a significant increase of NO2 mixing ratios, in the evening, when a fire plume reached the observations site. The increase of NO2 mixing ratios is well correlated (R=0.83) with that of particulate matter (PM), which is one of the primary product of forest and grassland fires. The tight correlation between NO2 and PM is used to improve the performance of a statistical regression model to simulate the observed O3, and to highlight the effect of fire emissions on the O3 mixing ratios. The statistical regression model of O3 improves in terms of performance (bias reduction of 77% and agreement enhancement of 10% for slope and correlation coefficient) when PM2.5 is included as additional input and proxy of the fire emissions among the usual input parameters (meteorological data and NO2 mixing ratios). A case study, comparing observed and modeled O3 in different days (with and without fire plume), suggests an impact of fire emissions on the O3 mixing ratios of about 10%.
Show more [+] Less [-]Assessing the mineral dust from North Africa over Portugal region using BSC–DREAM8b model Full text
2015
Alexandra, Monteiro | Ana Patricia, Fernandes | Carla, Gama | Carlos, Borrego | Oxana, Tchepel
Assessing the mineral dust from North Africa over Portugal region using BSC–DREAM8b model Full text
2015
Alexandra, Monteiro | Ana Patricia, Fernandes | Carla, Gama | Carlos, Borrego | Oxana, Tchepel
Over the last decade, air pollution has become a major problem in Portugal mainly due to the high concentrations of particulate matter in the atmosphere, which surpassed the daily limit values. An abundant type of natural atmospheric aerosol is related with the suspension and long–range transport of mineral dust from North Africa deserts. The main objective of this work was to assess the mineral dust over Portugal, namely in what concerns both long–term period (one year) and episode peaks. The BSC–DREAM8b v1.0 model was applied for the entire year of 2011 and the modeled surface concentrations were explored. The annual mean of the simulated dust has a magnitude of 2–6μg m–3. The monthly average analysis highlights the largest mineral dust average values in April and May (about 4μg m–3 higher than the other months). The influence of the transport of mineral dust from North Africa to Portugal is limited on time scale, since in 50% of the time this contribution is below 0.2μg m–3. Only when high percentiles are analyzed the dust surface concentrations over Portugal become relevant (>3μg m–3; with peak contribution around 10–25μg m–3). To characterize the strongest episodes of dust, a group of days with modeled surface daily concentrations above 5μg m–3 was selected, and data were extracted for 7 sites, spatially distributed along Portugal. A cluster analysis of the air parcels back trajectories that arrive at each site was performed in order to identify the mean flow patterns associated to each mineral dust episode. The prevalence of the flow regimes coming from North Africa during the episode days was different for the studied sites, with high frequency (above 70%) at south sites. This work contributes to the characterization and assessment of the dust episodes that affect Portugal, on a yearly basis and based on a modeling approach.
Show more [+] Less [-]Assessing the mineral dust from North Africa over Portugal region using BSC-DREAM8b model Full text
2015
Monteiro, Alexandra | Fernandes, Ana Patricia | Gama, Carla | Borrego, Carlos | Tchepel, Oxana
Over the last decade, air pollution has become a major problem in Portugal mainly due to the high concentrations of particulate matter in the atmosphere, which surpassed the daily limit values. An abundant type of natural atmospheric aerosol is related with the suspension and long–range transport of mineral dust from North Africa deserts. The main objective of this work was to assess the mineral dust over Portugal, namely in what concerns both long–term period (one year) and episode peaks. The BSC–DREAM8b v1.0 model was applied for the entire year of 2011 and the modeled surface concentrations were explored. The annual mean of the simulated dust has a magnitude of 2–6 μg m–3. The monthly average analysis highlights the largest mineral dust average values in April and May (about 4 μg m–3 higher than the other months). The influence of the transport of mineral dust from North Africa to Portugal is limited on time scale, since in 50% of the time this contribution is below 0.2 μg m–3. Only when high percentiles are analyzed the dust surface concentrations over Portugal become relevant (>3 μg m–3; with peak contribution around 10–25 μg m–3). To characterize the strongest episodes of dust, a group of days with modeled surface daily concentrations above 5 μg m–3 was selected, and data were extracted for 7 sites, spatially distributed along Portugal. A cluster analysis of the air parcels back trajectories that arrive at each site was performed in order to identify the mean flow patterns associated to each mineral dust episode. The prevalence of the flow regimes coming from North Africa during the episode days was different for the studied sites, with high frequency (above 70%) at south sites. This work contributes to the characterization and assessment of the dust episodes that affect Portugal, on a yearly basis and based on a modeling approach.
Show more [+] Less [-]Effects of sediments on the reproductive cycle of corals Full text
2015
Jones, R. | Ricardo, G.F. | Negri, A.P.
Dredging, river plumes and natural resuspension events can release sediments into the water column where they exert a range of effects on underlying communities. In this review we examine possible cause–effect pathways whereby light reduction, elevated suspended sediments and sediment deposition could affect the reproductive cycle and early life histories of corals. The majority of reported or likely effects (30+) were negative, including a suite of previously unrecognized effects on gametes. The length of each phase of the life-cycle was also examined together with analysis of water quality conditions that can occur during a dredging project over equivalent durations, providing a range of environmentally relevant exposure scenarios for future testing. The review emphasizes the need to: (a) accurately quantify exposure conditions, (b) identify the mechanism of any effects in future studies, and (c) recognize the close interlinking of proximate factors which could confound interpretation of studies.
Show more [+] Less [-]Persistent organic pollutants carried on plastic resin pellets from two beaches in China Full text
2015
Zhang, Weiwei | Ma, Xindong | Zhang, Zhifeng | Wang, Yan | Wang, Juying | Wang, Jing | Ma, Deyi
Microplastics provide a mechanism for the long-range transport of hydrophobic chemical contaminants to remote coastal and marine locations. In this study, plastic resin pellets were collected from Zhengmingsi Beach and Dongshan Beach in China. The collected pellets were analyzed for PAHs, PCBs, HCHs, DDTs, chlordane, heptachlor, endosulfan, aldrin, dieldrin and endrin. The total concentration of PCBs ranged from 34.7–213.7ngg−1 and from 21.5–323.2ngg−1 in plastic resin pellets for Zhengmingsi Beach and Dongshan Beach respectively. The highest concentrations of PCBs were observed for congeners 44, 110, 138, 155 and 200. The total concentration of PAHs ranged from 136.3–1586.9ngg−1 and from 397.6–2384.2ngg−1 in the plastic pellets, whereas DDTs concentration ranged from 1.2–101.5ngg−1 and from 1.5–127.0ngg−1 for the two beaches. The elevated concentrations of pollutants appear to be related to extensive industrial development, agricultural activity and the use of coal in the area.
Show more [+] Less [-]Heavy metals in red crabs, Chaceon quinquedens, from the Gulf of Mexico Full text
2015
Perry, Harriet | Isphording, Wayne | Trigg, Christine | Riedel, Ralf
The red crab, Chaceon quinquedens, is distributed in deep waters of the Gulf of Mexico (GOM) and is most abundant in an area associated with sediment deposition from the Mississippi River. Sediment geochemistry and biological and ecological traits of red crabs favor accumulation of contaminants. Red crabs, sediment, and bottom water samples were taken from three distinct geographic locations representing areas with differing exposure to contaminant laden effluents from the Mississippi River. Inductively coupled plasma spectrophotometry and atomic absorption spectrophotometry were employed to determine levels of heavy metals in red crab muscle tissue. Ion site partitioning was used to determine metal speciation in sediments. Red crabs showed evidence of heavy metal bioaccumulation in all sample areas with high variability in contaminant levels in individual crabs for some metals. Bioavailability of metals in sediment did not always result in accumulation in muscle tissue.
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