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Mercury levels in humpback whales, and other Southern Ocean marine megafauna
2021
Bengtson Nash, Susan M. | Casa, Maria Valeria | Kawaguchi, So | Staniland, Iain | Bjerregaard, Poul
Mercury is a known potent neurotoxin. The biogeochemical cycle of mercury in the remote Antarctic region is still poorly understood, with Polar climate change contributing added complexity. Longitudinal biomonitoring of mercury accumulation in Antarctic marine megafauna can contribute top-down insight into the bio-physical drivers of wildlife exposure. The bioaccumulative nature of organic mercury renders high trophic predators at the greatest risk of elevated exposure. Humpback whales represent secondary consumers of the Antarctic sea-ice ecosystem and an ideal biomonitoring species for persistent and bioaccumulative compounds due to their extended life-spans. This study provides the first results of mercury accumulation in humpback whales, and places findings within the context of mercury accumulation in both prey, as well as six other species of Antarctic marine megafauna. Combined, these findings contribute new baseline information regarding mercury exposure to Antarctic wildlife, and highlights methodological prerequisites for routine mercury biomonitoring in wildlife via non-lethally biopsied superficial tissues.
Afficher plus [+] Moins [-]Minimal meso-plastics detected in Australian coastal reef fish
2021
Puskic, Peter S. | Coghlan, Amy R.
Recording plastic ingestion across various species and spatial scales is key to elucidating the impact of plastic pollution on coastal and marine ecosystems. The effect of plastic ingestion on the diets, physiologies, and behaviors of selected fish species are well documented under laboratory settings. However, prevalence of plastic ingestion in wild fish across latitudinal gradients is yet to be widely documented; with a substantial lack of research in the Southern Hemisphere. We analyzed the gut content of reef fish across ~30ᵒ latitude of the east coast of Australia. Of 876 fish examined from 140 species (83 genera and 37 families), 12 individuals had visible (meso-plastics detectable to the naked eye) plastics present in the gut. Here, we present a first-look at plastic ingestion for coastal species with this region.
Afficher plus [+] Moins [-]Mysterious oil spill on the Brazilian coast – Part 2: A probabilistic approach to fill gaps of uncertainties
2021
Zacharias, Daniel Constantino | Gama, Carine Malagolini | Harari, Joseph | da Rocha, Rosmeri Porfirio | Fornaro, Adalgiza
Over 5000 tons of spilled oil reached the northeast coast of Brazil in 2019. The Laboratory for Computational Methods in Engineering (LAMCE/COPPE/UFRJ) employed time-reverse modeling and identify multiple potential source areas. As time-reverse modeling has many uncertainties, this article carried out a methodology study to mitigate them. A probabilistic modeling using Monte Carlo approach was developed to test these source areas with the Spill, Transport, and Fate Model (STFM) and a scenario tree methodology was used to select possible spill scenarios. To estimate the performance of Lagrangian models, two new model performance evaluations were added to Chang and Hanna (2004). The combination of probabilistic simulations, scenario tree analysis, and model performance evaluation proved to be a powerful tool for mitigating the uncertainties of time-reverse modeling, yielding good results and simple implementation.
Afficher plus [+] Moins [-]First assessment of anthropogenic marine debris in mangrove forests of Mauritius, a small oceanic island
2021
Seeruttun, Linisha Devi | Raghbor, Phanesh | Appadoo, Chandani
We evaluated the status of anthropogenic marine debris (AMD) in two natural mangrove forests on Mauritius, one of which in proximity to human settlement (Mahebourg) and the other more remote (Ferney). AMD was collected monthly from October to December 2018 in 1500 m² at both sites and classified into material composition and their potential sources. In all, 2127 items (150.07 kg) was sampled at Mahebourg and 1098 items (43.71 kg) at Ferney. In line with global studies, plastic made up most of the debris in terms of both count (42.92%, 43.66%) and total weight (40.65%, 32.08%) at Mahebourg and Ferney respectively. Most debris originated from shoreline and recreational activities. This work sets a baseline to assess impacts of AMD on mangroves, public awareness required and future strategies for waste monitoring and management in mangroves that may be applied both locally and on other small islands.
Afficher plus [+] Moins [-]Impact of Port and harbour activities on plankton distribution and dynamics: A multivariate approach
2021
Shaikh, Siratun Montaha S. | Tagde, Jyoti P. | Singh, Pooja R. | Dutta, Smita | Sangolkar, Lalita N. | Suresh Kumar, M.
Numerous researches have been conducted to study the impact of Port activities on water quality. However, investigation on the response of the inhabiting biota to Port related extrinsic factors is extremely limited. Using Canonical Correspondence Analysis, comprehensive assessment of plankton population dynamics and distribution corresponding to the spatial heterogeneity in physico-chemical characteristics of harbour and adjacent coastal water is conducted. The results revealed resource competition for nitrate, predator mediated co-existence of species favoured by active switching and Port influenced environmental filtering due to suspended solids, and oil and grease as the predominant factor to modulate the plankton community structure and succession in harbour. The higher heterogeneity in the measured environmental variables at coast revealed dispersion of nutrient and other pollutants from harbour into the adjacent coastal water during ebb tide. Our results indicate reengineering of Port infrastructures and efficient management policies including water quality standards to facilitate proper water circulation and minimize pollution with a long term goal to reconcile economic interest with ecosystem conservation.
Afficher plus [+] Moins [-]Effects of suspended coal particles on gill structure and oxygen consumption rates in a coral reef fish
2021
Berry, K.L.E. | Hess, S. | Clark, T.D. | Wenger, A.S. | Hoogenboom, M.O. | Negri, A.P.
Large quantities of coal are transported through tropical regions; however, little is known about the sub-lethal effects of coal contamination on tropical marine organisms, including fish. Here, we measured aerobic metabolism and gill morphology in a planktivorous coral reef damselfish, Acanthochromis polyacanthus to elucidate the sub-lethal effects of suspended coal particles over a range of coal concentrations and exposure durations. Differences in the standard oxygen consumption rates (MO₂) between control fish and fish exposed to coal particles (38 and 73 mg L⁻¹) were minimal and generally not dose dependent; however, the MO₂ of fish exposed to 38 mg coal L⁻¹ (21 days) and 73 mg coal L⁻¹ (31 days) were both significantly higher than the MO₂ of control fish. Chronic coal exposure (31 days) altered gill structure in the higher coal treatments (73 and 275 mg L⁻¹), with fish exposed to 275 mg L⁻¹ exhibiting significant reductions in gill mucous and thinning of lamellar and filament epithelium. These findings contribute to our limited understanding of the potential impacts of coal on tropical reef species; however, most of the observed effects occurred at high coal concentrations that are unlikely under most coal spill scenarios. Future studies should investigate other contamination scenarios such as the impacts of chronic exposures to lower concentrations of coal.
Afficher plus [+] Moins [-]Oil impact on the environment and aquatic organisms on the coasts of the states of Alagoas and Sergipe, Brazil - A preliminary evaluation
2021
Soares, Emerson Carlos | Bispo, Mozart Daltro | Vasconcelos, Vivian Costa | Soletti, João Inácio | Carvalho, Sandra Helena Vieira | de Oliveira, Maria Janaína | dos Santos, Mayara Costa | dos Santos Freire, Emerson | Nogueira, Aryanna Sany Pinto | da Silva Cunha, Francisco Antônio | Sandes, Rafael Donizete Dutra | dos Santos, Raquel Anne Ribeiro | Neta, Maria Terezinha Santos Leite | Narain, N. (Narendra) | Garcia, Carlos Alexandre Borges | da Costa, Silvânio Silvério Lopes | Santos, Josué Carinhanha Caldas
The oil spill off the coast of the Brazilian Northeast region is one of the most significant global events regarding contamination and environmental impact in recent years. This work evaluates the effects of oil spills on the Northeast coasts between Alagoas and Sergipe states from October 2019 to January 2020. Analysis of some sampling points of seawater revealed the presence of Hg, Cd, Pb, and Cu in levels above the maximum concentration limits established by the Brazilian legislation. For water quality parameters, phosphorus, nitrite, and turbidity showed statistically different values. However, the chromatographic profiles of oil obtained from different beaches were quite similar. Seawater, fishes, and massunins (bivalve) presented the main polycyclic aromatic hydrocarbons: naphthalene, phenanthrene, fluoranthene, fluorene, and acenaphthalene. Therefore, the concentration of organic and inorganic contaminants determined in different environmental locations served as a subsidy to assess the effect of the preliminary oil spill on the Brazilian coast.
Afficher plus [+] Moins [-]Dispersion of hazardous nanoparticles on beaches around phosphogypsum factories
2021
Silva, Luis F.O. | Pinto, Diana | Oliveira, Marcos L.S. | Dotto, Guilherme L.
Anthropogenic occurring nanoparticles (NPs) have been one of the principal catalytic components of marine pollution throughout its history. The phosphogypsum (PG) factories present environmental risks and evident marine pollution in different parts of the world. Many of these factors continue to operate, however, some have already been abandoned by the private sector. The general objective of this manuscript is to analyze the real nanoparticles (NPs) present on a beach in southern Brazil to illustrate the need to create public policies and projects for environmental recovery. This work focused on real representative sampling of suspended sediments (SSs), and on a modern analytical procedure via advanced electron microscopes (field emission scanning electron microscope-FE-SEM and high resolution transmission electron microscope-HR-TEM coupled with an energy dispersive X-ray microanalysis system-EDS) to analyze NPs containing hazardous elements (HEs). The results presented in this work demonstrate who the size, morphology, among other physical-geochemical characteristics influence in the adsorption of HEs by the NPs and their respective agglomerates. This study is of great importance for carrying out the application of advanced techniques and methods to better understand the formation and transport of NPs on beaches, which allows assisting in the management of waste from plaster factories on a global scale.
Afficher plus [+] Moins [-]New tools to evaluate plastic ingestion by northern fulmars applied to North Sea monitoring data 2002–2018
2021
van Franeker, Jan A. | Kuhn, Susanne | Anker-Nilssen, Tycho | Edwards, Ewan W.J. | Gallien, Fabrice | Guse, Nils | Kakkonen, Jenni E. | Mallory, Mark L. | Miles, Will | Olsen, Kåre Olav | Pedersen, John | Provencher, Jennifer | Roos, Mervyn | Stienen, Eric | Turner, Daniel M. | van Loon, Willem M.G.M.
Monitoring plastic in stomachs of beached northern fulmars for OSPAR's Ecological Quality Objectives (EcoQOs) has been incorporated into the European Marine Strategy Framework Directive (MSFD). This paper aims to provide the appropriate tools to interpret the monitoring results. MSFD requires a data-derived threshold value (Fulmar-TV) representing ‘Good Environmental Status’. Such Fulmar-TV was calculated from near-pristine Canadian Arctic data where 10.06% of fulmars exceeded the level of 0.1 g ingested plastic. This Fulmar-TV is almost identical to the earlier OSPAR EcoQO, arbitrarily set at 10%. The MSFD approach was evaluated for 2661 North Sea fulmars in 2002–2018. Between 2014 and 2018, 51% of 393 fulmars exceeded 0.1 g plastic, significantly above the proposed Fulmar-TV. Linear regression of individual ingested plastic mass over the 2009–2018 period indicates a significant decrease. Over the longer term 2002–2018, logistic regression of annual EcoQ% shows a significant decline and predicts compliance with the Fulmar-TV by 2054.
Afficher plus [+] Moins [-]Drones for litter mapping: An inter-operator concordance test in marking beached items on aerial images
2021
Unmanned aerial systems (UAS, aka drones) are being used to map macro-litter on the environment. Sixteen qualified researchers (operators), with different expertise and nationalities, were invited to identify, mark and categorize the litter items (manual image screening, MS) on three UAS images collected at two beaches.The coefficient of concordance (W) among operators varied between 0.5 and 0.7, depending on the litter parameter (type, material and colour) considered. Highest agreement was obtained for the type of items marked on the highest resolution image, among experts in litter surveys (W = 0.86), and within territorial subgroups (W = 0.85). Therefore, for a detailed categorization of litter on the environment, the MS should be performed by experienced and local operators, familiar with the most common type of litter present in the target area. This work provides insights for future operational improvements and optimizations of UAS-based images analysis to survey environmental pollution.
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