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Assessing confinement in coastal lagoons
2012
Measures of transport scale in aquatic systems can contribute to the formulation of definitions of indicators of the system’s ecological properties. This paper addresses confinement, a specific transport scale proposed by biological scientists as a parameter that can capture and synthesize the principal properties that determine the spatial structure of biological communities in transitional environments. Currently, there is no direct experimental measure of confinement. In this study, a methodology based on the accumulation rate within a lagoon of a passive tracer of marine origin is proposed, the influences of different factors in the calculation of confinement are analyzed, and general recommendations are derived. In particular, we analyze the spatial and the temporal variability of confinement and its sensitivity to the seasonal variability of climatic forcing, the inputs from rivers and the parameterization of the tidal exchanges. The Lagoon of Venice is used as a case study.
Afficher plus [+] Moins [-]Thermal treatment as a method to control transfers of invasive biofouling species via vessel sea chests
2012
Piola, Richard F. | Hopkins, Grant A.
This study examined the efficacy of heated seawater for the treatment and remediation of fouled vessel sea chest habitats. In laboratory trials, three temperature regimes (37.5°C for 60min, 40°C for 30min and 42.5°C for 20min) were tested on a range of temperate taxa commonly found in sea chests. Field validation trials further assessed the efficacy of heat treatment within a replica sea chest environment. During laboratory trials, 100% mortality was achieved across all three treatments for the majority of taxa; the exceptions being the barnacle Elminius modestus and the oyster Crassostrea gigas. Temperature tolerance limits observed in the laboratory were successfully replicated under simulated sea chest conditions; however, a failure to achieve even heat distribution was an obstacle to achieving uniform mortality. This study provides guidance on the temperature/exposure parameters required for vessels plying temperate latitudes, and demonstrates that heated seawater has potential for controlling biofouling in vessel sea chests.
Afficher plus [+] Moins [-]Identifying fluorescent pulp mill effluent in the Gulf of Maine and its watershed
2012
Cawley, Kaelin M. | Butler, Kenna D. | Aiken, George R. | Larsen, Laurel G. | Huntington, Thomas G. | McKnight, Diane M.
Using fluorescence spectroscopy and parallel factor analysis (PARAFAC) we characterized and modeled the fluorescence properties of dissolved organic matter (DOM) in samples from the Penobscot River, Androscoggin River, Penobscot Bay, and the Gulf of Maine (GoM). We analyzed excitation-emission matrices (EEMs) using an existing PARAFAC model (Cory and McKnight, 2005) and created a system-specific model with seven components (GoM PARAFAC). The GoM PARAFAC model contained six components similar to those in other PARAFAC models and one unique component with a spectrum similar to a residual found using the Cory and McKnight (2005) model. The unique component was abundant in samples from the Androscoggin River immediately downstream of a pulp mill effluent release site. The detection of a PARAFAC component associated with an anthropogenic source of DOM, such as pulp mill effluent, demonstrates the importance for rigorously analyzing PARAFAC residuals and developing system-specific models.
Afficher plus [+] Moins [-]Persistent organic pollutants in the endangered Hawaiian monk seal (Monachus schauinslandi) from the main Hawaiian Islands
2012
Bohlander, Jessica | Boyd, Daryle | Ylitalo, Gina M. | Littnan, Charles | Pearce, R. (Ronald)
Little is known about levels or effects of persistent organic pollutants (POPs) in Hawaiian monk seals (HMS) from the main Hawaiian Islands (MHI) subpopulation. This study examined concentrations of a large suite of POPs in blubber and serum of juvenile and adult HMS from the MHI. Adult females have the lowest blubber levels of most POPs, whereas adult males have highest levels. POPs in serum were significantly different in adult males compared with adult females for chlordanes and summed dichlorodiphenyltrichloroethanes (DDTs). Lipid-normalized concentrations of chlordanes, DDTs, polychlorinated biphenyls, and mirex in paired blubber and serum samples were significantly correlated. Contaminant levels from the MHI were at similar or lower levels than those from remote Northwestern Hawaiian Island populations. Determining initial ranges of POPs is an important step towards assessing one of the many potential health threats to this critically endangered species.
Afficher plus [+] Moins [-]Evaluation of the ecotoxicity and biological efficacy of ship’s ballast water treatment based on hydroxyl radicals technique
2012
Zhang, Nahui | Zhang, Zhitao | Bai, Mindong | Chen, Cao | Meng, Xiangying | Tian, Yiping
Ballast water has been identified as one of the key pathways for the movement of species between different ecosystems. The purpose of this study is to evaluate the biological efficacy and the potential toxicological impact of a proposed ballast water treatment using hydroxyl radicals as the main active substances. Living biomass of organisms kept in treated water for 2days met the requirement stated in the International Maritime Organization (IMO) Ballast Water Convention (Regulation D-2), and no re-growth was observed over a period of 5days. Aquatic toxicity tests of three trophic levels for the treated ballast water were performed. The results indicated that the toxicological risk of the discharge water to the receiving environment was not significant.
Afficher plus [+] Moins [-]Survival and movements of Magellanic penguins rehabilitated from oil fouling along the coast of South America, 2000–2010
2012
Ruoppolo, Valeria | Vanstreels, Ralph Eric Thijl | Woehler, E. J. (Eric J.) | Heredia, Sergio Andres Rodríguez | Adornes, Andréa Corrado | Silva-Filho, Rodolfo Pinho da | Matus, Ricardo | Poleschi, Carla | Griot, Karen | Kolesnikovas, Cristiane K Miyaji | Serafini, Patrícia
Oil pollution is a significant conservation concern. We examined data from six institutions along the coast of South America: Emergency Relief Team of the International Fund for Animal Welfare, Fundación Mundo Marino, Centro de Recuperação de Animais Marinhos, Natura Patagonia, Associação R3 Animal, and Mar del Plata Aquarium and data from resightings in Argentina, Brazil, Chile and Falkland/Malvinas Islands. From 2000 to 2010, 2183 oiled Magellanic penguins were rehabilitated as part of the routine activities of these institutions or during emergency responses to eight oil spills in which they were involved; all rehabilitated penguins were flipper banded and released. Since their release, 41 penguins were resighted until 31 December 2011. The results demonstrate that, when combined with other prevention strategies, the rehabilitation of Magellanic penguins is a strategy that contributes to the mitigation of adverse effects of oil spills and chronic pollution to the species.
Afficher plus [+] Moins [-]Assessing sound exposure from shipping in coastal waters using a single hydrophone and Automatic Identification System (AIS) data
2012
Merchant, Nathan D. | Witt, Matthew J. | Blondel, Philippe | Godley, Brendan J. | Smith, George H.
Underwater noise from shipping is a growing presence throughout the world’s oceans, and may be subjecting marine fauna to chronic noise exposure with potentially severe long-term consequences. The coincidence of dense shipping activity and sensitive marine ecosystems in coastal environments is of particular concern, and noise assessment methodologies which describe the high temporal variability of sound exposure in these areas are needed. We present a method of characterising sound exposure from shipping using continuous passive acoustic monitoring combined with Automatic Identification System (AIS) shipping data. The method is applied to data recorded in Falmouth Bay, UK. Absolute and relative levels of intermittent ship noise contributions to the 24-h sound exposure level are determined using an adaptive threshold, and the spatial distribution of potential ship sources is then analysed using AIS data. This technique can be used to prioritise shipping noise mitigation strategies in coastal marine environments.
Afficher plus [+] Moins [-]A unique aspect of ballast water management requirements – The same location concept
2012
Gollasch, Stephan | David, Matej
Under certain circumstances vessels do not need to meet ballast water management requirements as stated in the International Convention for the Management and Control of Ballast Water and Sediments (BWM Convention). Besides exceptions to ensure e.g., (a) the safety of a ship, (b) discharge of ballast water for the purpose of avoiding or minimizing pollution incidents, (c) uptake and discharge on high seas of the same ballast water, the same location concept comes into play as ballast water discharges from a ship at the same location where it was taken up is also excepted from BWM requirements. The term same location was not defined in this instrument, hence it is exposed to different interpretations (e.g., a terminal, a port, a larger area where two or more ports may be located). As the BWM Convention is an instrument with biological meaning, the authors recommend a biologically meaningful definition of the same location in this contribution.
Afficher plus [+] Moins [-]Northern fulmars as biological monitors of trends of plastic pollution in the eastern North Pacific
2012
Avery-Gomm, Stephanie | O’Hara, Patrick D. | Kleine, Lydia | Bowes, Victoria | Wilson, Laurie K. | Barry, Karen L.
Marine plastic debris is a global issue, which highlights the need for internationally standardized methods of monitoring plastic pollution. The stomach contents of beached northern fulmar (Fulmarus glacialis) have proven a cost-effective biomonitor in Europe. However, recent information on northern fulmar plastic ingestion is lacking in the North Pacific. We quantified the stomach contents of 67 fulmars from beaches in the eastern North Pacific in 2009–2010 and found that 92.5% of fulmars had ingested an average of 36.8 pieces, or 0.385g of plastic. Plastic ingestion in these fulmars is among the highest recorded globally. Compared to earlier studies in the North Pacific, our findings indicate an increase in plastic ingestion over the past 40years. This study substantiates the use of northern fulmar as biomonitors of plastic pollution in the North Pacific and suggests that the high levels of plastic pollution in this region warrant further monitoring.
Afficher plus [+] Moins [-]Bacterial communities are sensitive indicators of contaminant stress
2012
Sun, Melanie Y. | Dafforn, Katherine A. | Brown, Mark V. | Johnston, Emma L.
With many environments worldwide experiencing at least some degree of anthropogenic modification, there is great urgency to identify sensitive indicators of ecosystem stress. Estuarine organisms are particularly vulnerable to anthropogenic contaminants. This study presents bacterial communities as sensitive indicators of contaminant stress. Sediments were collected from multiple sites within inner and outer zones of three heavily modified and three relatively unmodified estuaries. Bacterial communities were censused using Automated Ribosomal Intergenic Spacer Analysis and analysed for a suite of metal and PAH contaminants. Shifts in both bacterial community composition and diversity showed strong associations with sediment contaminant concentrations, particularly with metals. Importantly, these changes are discernable from environmental variation inherent to highly complex estuarine environments. Moreover, variation in bacterial communities within sites was limited. This allowed for differences between sites, zones and estuaries to be explained by variables of interest such as contaminants that vary between, but not within individual sites.
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