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Limited impact of several years of pretreated wastewater discharge on fauna and vegetation in a mangrove ecosystem Full text
2018
Capdeville, C. | Abdallah, K. | Buffan-Dubau, E. | Lin, C. | Azemar, F. | Lambs, L. | Fromard, F. | Rols, J.L. | Leflaive, J.
It was hypothesized that mangroves, tropical wetlands, could be used for the finishing treatment of domestic wastewaters. Our aim was to determine if a nutrient-stressed mangrove could tolerate long-term discharges of pretreated wastewater (PW). Since 2008, in an in situ experimental system set up in Mayotte Island (Indian Ocean), domestic PW are discharged into two impacted areas (675 m2) dominated by different species of mangrove trees. Anthropogenic inputs during > 4.5 years led to an increase in vegetation growth associated with an increase in leaf pigment content, leaf surface and tree productivity. A marked increase in tree mortality was observed. There was no effect on crabs and meiofauna densities, but significant modifications of community structures. These effects may be directly linked to PW inputs, or indirectly to the modifications of the environment associated with higher tree growth. However, our results indicate that there was no major dysfunction the ecosystem.
Show more [+] Less [-]An evaluation of cumulative risks from offshore produced water discharges in the Bass Strait Full text
2018
Parkerton, T.F. | Bok, M. | Ireland, A.W. | Prosser, C.M.
Chemical analyses and toxicity testing using six marine species were used to characterize the hazard of produced waters (PW) to marine life from twelve Australian offshore platforms. Hazard data were used in conjunction with platform-specific plume discharge dilution and species sensitivity distribution modeling to estimate cumulative risks by calculating the multiple substance potentially affected fraction of species in the local marine environment. Results provided two independent lines of evidence demonstrating that cumulative risks to marine life from these discharges meet intended 95% species protection goals at the edge of the mixing zone. A limited number of PW constituents (hydrocarbons, sulphide and ammonia) appeared to dictate risk thereby informing management and providing a rationale for more targeted analyses in future monitoring studies. Based on these findings a tiered framework is proposed to foster consistent screening and potential refinement of cumulative risk evaluations for PW discharges.
Show more [+] Less [-]Spatial distribution of marine litter along italian coastal areas in the Pelagos sanctuary (Ligurian Sea - NW Mediterranean Sea): A focus on natural and urban beaches Full text
2018
Giovacchini, Alice | Merlino, Silvia | Locritani, Marina | Stroobant, Mascha
Our paper will show data on quantity, typology, distribution of beach litter (Anthropogenic Marine Debris - AMD) within a coastal macroarea surrounding the Pelagos Sanctuary, an International Protected Area in the NW Mediterranean Sea. AMD Monitoring and characterisation have been performed by using SEACleaner Protocol: an adapted version of UNEP/IOC, OSPAR and EU guidelines. 11 beaches located in 5 different areas, have been monitored with a total amount of thirty three surveys, from January 2014 to December 2015, during different seasons. Three kinds of beaches have been considered: Natural (belonging to MPAs), Urbanized and Urban. A total of 34,027 items on a total area of 32,154 m2 have been removed and classified. Spatial difference in abundance and composition of AMDs - as well as beach environmental quality - has been detected. Natural sites, and particularly protected areas close to river mouths show a major density compared to other areas.
Show more [+] Less [-]Marine introduced species in Australia, where to from here? A personal perspective from a practising taxonomist Full text
2018
Hutchings, Pat
While introduced marine species have been arriving in Australia for centuries, it was the advent of container shipping and the discharge of ballast water into Australian ports that highlighted the problem. A summary is provided of how Australia responded to this challenge and continues to. More recently there has been an acceptance that hull fouling is also an important vector of introductions. A major problem in Australia is distinguishing introduced species from as yet undescribed native species. This is a particular problem in northern Australia where the native fauna is poorly documented. Despite the economic and environmental threats posed by introduced species, the impetus to undertake expensive comprehensive surveys has declined and attention is now focusing on targeted surveys especially of known marine pest species and molecular data to identify introductions. Ongoing research is still needed to monitor other species identified as being introduced and their potential to become pests.
Show more [+] Less [-]Sorption and desorption of selected pharmaceuticals by polyethylene microplastics Full text
2018
Razanajatovo, Roger Mamitiana | Ding, Jiannan | Zhang, Shanshan | Jiang, Hang | Zou, Hua
The aim of the present study was to evaluate the sorption and desorption of sulfamethoxazole (SMX), propranolol (PRP) and sertraline (SER) by polyethylene (PE) microplastics in water. After the 96 h mixture, the sorption percentages of pharmaceuticals on PE microplastics decreased according to the following order: SER (28.61%) > PRP (21.61%) > SMX (15.31%). The sorption kinetics were fitted well with the pseudo-second-order model. Both linear and Freundlich models were able to describe the sorption isotherm. The results suggest that the sorption process of the pharmaceuticals may be adequately described by their hydrophobicity and electrostatic interactions. The desorption results showed that 8% and 4% of PRP and SER, respectively, were released from the microplastics within 48 h, but the sorption of SMX was irreversible. The results indicate the potential risks of PRP and SER for bioaccumulation in aquatic organisms via ingestion of the microplastics in aquatic environments.
Show more [+] Less [-]Litter impacts on beach/dune systems along the Atlantico Department, the Caribbean Coastline of Colombia Full text
2018
Rangel-Buitrago, Nelson | Castro-Barros, Julian Dario | Adriana Gracia, C. | Villadiego, Jose Dario Villamil | Williams, Allan T.
Eight beach/dune systems located along the Atlantico Department, Caribbean coast of Colombia were surveyed to determine litter influences over its scenic quality. Application of the Coastal Scenic Evaluation System (CSES) categorized these systems into two of the five available classes. Five of the investigated beach/dune systems belong to Class IV, while three systems correspond to V. Classes I, II and III were not found. Along these beach/dune systems, a total amount of 1908 litter items were collected with average abundances of 4.2 items/m2. Currently, 82% of surveyed sites are under an unacceptable condition of cleanness. User's habits as well as bad litter management practices are directly responsible for the decline of scenic quality of the Atlantico Department beach/dune systems. Litter management must be centered on strategies to eliminate or minimize litter sources. Specific remedial actions need to be defined and developed.
Show more [+] Less [-]Urban coral reefs: Degradation and resilience of hard coral assemblages in coastal cities of East and Southeast Asia Full text
2018
Heery, Eliza C. | Hoeksema, Bert W. | Browne, Nicola K. | Reimer, James D. | Ang, Put O. | Huang, Danwei | Friess, Daniel A. | Chou, L. M. | Loke, Lynette H.L. | Saksena-Taylor, Poonam | Alsagoff, Nadia | Yeemin, Thamasak | Sutthacheep, Makamas | Vo, Si Tuan | Bos, Arthur R. | Gumanao, Girley S. | Syed Hussein, Muhammad Ali | Waheed, Zarinah | Lane, David J.W. | Johan, Ofri | Kunzmann, Andreas | Jompa, Jamaluddin | Suharsono, | Taira, Daisuke | Bauman, Andrew G. | Todd, Peter A.
Given predicted increases in urbanization in tropical and subtropical regions, understanding the processes shaping urban coral reefs may be essential for anticipating future conservation challenges. We used a case study approach to identify unifying patterns of urban coral reefs and clarify the effects of urbanization on hard coral assemblages. Data were compiled from 11 cities throughout East and Southeast Asia, with particular focus on Singapore, Jakarta, Hong Kong, and Naha (Okinawa). Our review highlights several key characteristics of urban coral reefs, including “reef compression” (a decline in bathymetric range with increasing turbidity and decreasing water clarity over time and relative to shore), dominance by domed coral growth forms and low reef complexity, variable city-specific inshore-offshore gradients, early declines in coral cover with recent fluctuating periods of acute impacts and rapid recovery, and colonization of urban infrastructure by hard corals. We present hypotheses for urban reef community dynamics and discuss potential of ecological engineering for corals in urban areas.
Show more [+] Less [-]Using a genetic algorithm to improve oil spill prediction Full text
2018
Guo, Weijun | Jiang, Meirong | Li, Xueyan | Ren, Bing
The performance of oil spill models is strongly influenced by multiple parameters. In this study, we explored the ability of a genetic algorithm (GA) to determine optimal parameters without the need for time-consuming manual attempts. An evaluation function integrating the percentage of coincidence between the predicted polluted area and the observed spill area was proposed for measuring the performance of a Lagrangian oil particle model. To maximise the objective function, the oil spill was run numerous times with continuously optimised parameters. After many generations, the GA effectively reduced discrepancies between model results and observations of a real oil spill. Subsequent validation indicated that the oil spill model predicted oil slick patterns with reasonable accuracy when equipped with optimal parameters. Furthermore, multiple objective optimisation for observations at different times contributed to better model performance.
Show more [+] Less [-]Assessing vessel slowdown for reducing auditory masking for marine mammals and fish of the western Canadian Arctic Full text
2018
Pine, Matthew K. | Hannay, David E. | Insley, Stephen J. | Halliday, William D. | Juanes, Francis
Vessel slowdown may be an alternative mitigation option in regions where re-routing shipping corridors to avoid important marine mammal habitat is not possible. We investigated the potential relief in masking in marine mammals and fish from a 10 knot speed reduction of container and cruise ships. The mitigation effect from slower vessels was not equal between ambient sound conditions, species or vessel-type. Under quiet ambient conditions, a speed reduction from 25 to 15 knots resulted in smaller listening space reductions by 16–23%, 10–18%, 1–2%, 5–8% and 8% respectively for belugas, bowheads, bearded seals, ringed seals, and fish, depending on vessel-type. However, under noisy conditions, those savings were between 9 and 19% more, depending on the species. This was due to the differences in species' hearing sensitivities and the low ambient sound levels measured in the study region. Vessel slowdown could be an effective mitigation strategy for reducing masking.
Show more [+] Less [-]Barriers and benefits to desired behaviors for single use plastic items in northeast Ohio's Lake Erie basin Full text
2018
Bartolotta, Jill F. | Hardy, Scott D.
Given the growing saliency of plastic marine debris, and the impact of plastics on beaches and aquatic environments in the Laurentian Great Lakes, applied research is needed to support municipal and nongovernmental campaigns to prevent debris from reaching the water's edge. This study addresses this need by examining the barriers and benefits to positive behavior for two plastic debris items in northeast Ohio's Lake Erie basin: plastic bags and plastic water bottles. An online survey is employed to gather data on the use and disposal of these plastic items and to solicit recommendations on how to positively change behavior to reduce improper disposal. Results support a ban on plastic bags and plastic water bottles, with more enthusiasm for a bag ban. Financial incentives are also seen as an effective way to influence behavior change, as are location-specific solutions focused on education and outreach.
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