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A review of unmanned vehicles for the detection and monitoring of marine fauna Texte intégral
2019
Verfuss, Ursula K. | Aniceto, Ana Sofia | Harris, Danielle V. | Gillespie, Douglas | Fielding, Sophie | Jiménez, Guillermo | Johnston, Phil | Sinclair, Rachael R. | Sivertsen, Agnar | Solbø, Stian A. | Storvold, Rune | Biuw, Martin | Wyatt, Roy
Recent technology developments have turned present-day unmanned systems into realistic alternatives to traditional marine animal survey methods. Benefits include longer survey durations, improved mission safety, mission repeatability, and reduced operational costs. We review the present status of unmanned vehicles suitable for marine animal monitoring conducted in relation to industrial offshore activities, highlighting which systems are suitable for three main monitoring types: population, mitigation, and focal animal monitoring. We describe the technical requirements for each of these monitoring types and discuss the operational aspects. The selection of a specific sensor/platform combination depends critically on the target species and its behaviour. The technical specifications of unmanned platforms and sensors also need to be selected based on the surrounding conditions of a particular offshore project, such as the area of interest, the survey requirements and operational constraints.
Afficher plus [+] Moins [-]Pinniped entanglement in oceanic plastic pollution: A global review Texte intégral
2019
Jepsen, Emma M. | de Bruyn, P.J Nico
Oceanic plastic pollution is a growing worldwide environmental concern, endangering numerous marine species. Pinnipeds are particularly susceptible to entanglement, especially in abandoned, lost or discarded fishing gear and packaging straps. We searched three international databases to compile a comprehensive review of all reported pinniped entanglements over the last 40 years, with the aim to identify areas of concern and foci for mitigation. The majority of published records of entanglement emanate from North America and Oceania and are focused on a few populous species (notably, Zalophus californianus and Arctocephalus gazella). Reporting bias, skewed research effort and incomplete understanding of plastic pollution and pinniped abundance overlap, combine to cloud our understanding of the entanglement problem. Broader geographical effort in entanglement data collection, reporting of such data, and improved quantification of the proportions of populations, sexes and ages that are most susceptible, will aid our efforts to pinpoint priority mitigation measures.
Afficher plus [+] Moins [-]Contribution of fluorite mining waste to mercury contamination in coastal systems Texte intégral
2019
Forján, Rubén | Baragaño, Diego | Boente, Carlos | Fernández-Iglesias, Elena | Rodríguez-Valdes, Eduardo | Gallego, J.R.
Contribution of fluorite mining waste to mercury contamination in coastal systems Texte intégral
2019
Forján, Rubén | Baragaño, Diego | Boente, Carlos | Fernández-Iglesias, Elena | Rodríguez-Valdes, Eduardo | Gallego, J.R.
Samples from 13 beaches along the northern Spanish coast, a region with a history of heavy industries, were first screened to identify signs of pollution. High concentrations of Hg and Ba on Vega beach were found, both elements belong to the fluorite ore paragenesis, mined in the surroundings. Samples of beach and fluvial sediments, and nearby soils were collected in Vega beach area to address potential Hg pollution, fate and sources. Most samples showed a similar pollutants fingerprint to that of beach samples, especially those taken from white dunes, registering notable Hg concentrations. Hg was enriched in the finer fractions, and overall the main input was attributed to the mining waste discharged along the coast in the past. Although a specific risk assessment and study of the submerged sediments are advisable for this area, Hg bioavailability and methylation were low, thus indicating that this metal poses a reduced environmental risk.
Afficher plus [+] Moins [-]Contribution of fluorite mining waste to mercury contamination in coastal systems Texte intégral
2019
Forján Castro, Rubén | Baragaño Coto, Diego | Boente López, Carlos | Fernández Iglesias, María Elena | Rodríguez-Valdés Rodríguez, Eduardo | Rodríguez Gallego, José Luis
This research was partially funded by the project LIFE13 NAT/ES/000883 (LIFE ARCOS) and by the government of the Principality of Asturias
Afficher plus [+] Moins [-]Tools and constraints in monitoring interactions between marine litter and megafauna: Insights from case studies around the world Texte intégral
2019
Claro, F. | Fossi, M.C. | Ioakeimidis, C. | Baini, M. | Lusher, A.L. | Mc Fee, W. | McIntosh, R.R. | Pelamatti, T. | Sorce, M. | Galgani, F. | Hardesty, B.D.
Tools and constraints in monitoring interactions between marine litter and megafauna: Insights from case studies around the world Texte intégral
2019
Claro, F. | Fossi, M.C. | Ioakeimidis, C. | Baini, M. | Lusher, A.L. | Mc Fee, W. | McIntosh, R.R. | Pelamatti, T. | Sorce, M. | Galgani, F. | Hardesty, B.D.
Adverse impacts of marine litter is documented on >1400 species, including marine megafauna (fish, birds, sea turtles and mammals). The primary impacts include ingestion and entanglement, and there is increasing concern about chemical contamination via ingestion. Numerous survey approaches and monitoring programs have been developed and implemented around the world. They may aim to provide data about parameters such as species distribution and interactions with anthropogenic activities. During the Sixth International Marine Debris Conference, a session was dedicated to the tools and constraints in monitoring interactions between litter and megafauna. In the present paper, we summarize 7 case studies which discuss entanglement and ingestion including macro- and micro-debris in several taxa and across multiple geographic regions. We then discusses the importance of tools and standardizing methods for assessment and management purposes, in the context of international environmental policies and marine litter strategies.
Afficher plus [+] Moins [-]Tools and constraints in monitoring interactions between marine litter and megafauna: Insights from case studies around the world Texte intégral
2019
Claro, F | Fossi, Mc | Ioakeimidis, C | Baini, M | Lusher, Al | Mc Fee, W | Mcintosh, Rr | Pelmatti, T | Sorce, M | Galgani, Francois | Hardesky, Bd
Adverse impacts of marine litter is documented on >1400 species, including marine megafauna (fish, birds, sea turtles and mammals). The primary impacts include ingestion and entanglement, and there is increasing concern about chemical contamination via ingestion. Numerous survey approaches and monitoring programs have been developed and implemented around the world. They may aim to provide data about parameters such as species distribution and interactions with anthropogenic activities. During the Sixth International Marine Debris Conference, a session was dedicated to the tools and constraints in monitoring interactions between litter and megafauna. In the present paper, we summarize 7 case studies which discuss entanglement and ingestion including macro- and micro-debris in several taxa and across multiple geographic regions. We then discusses the importance of tools and standardizing methods for assessment and management purposes, in the context of international environmental policies and marine litter strategies.
Afficher plus [+] Moins [-]Tools and constraints in monitoring interactions between marine litter and megafauna: Insights from case studies around the world Texte intégral
2019
Claro, Francoise | Fossi, Maria Cristina | Ioakeimidis, Christos | Baini, Matteo | Lusher, Amy L | McFee, Wayne | McIntosh, Rebecca Ruth | Pelamatti, Tania | Sorce, Meaghan | Galgani, François | Hardesty, Britta Denise
Embargo until 22 Feb 2021 | Adverse impacts of marine litter is documented on >1400 species, including marine megafauna (fish, birds, sea turtles and mammals). The primary impacts include ingestion and entanglement, and there is increasing concern about chemical contamination via ingestion. Numerous survey approaches and monitoring programs have been developed and implemented around the world. They may aim to provide data about parameters such as species distribution and interactions with anthropogenic activities. During the Sixth International Marine Debris Conference, a session was dedicated to the tools and constraints in monitoring interactions between litter and megafauna. In the present paper, we summarize 7 case studies which discuss entanglement and ingestion including macro- and micro-debris in several taxa and across multiple geographic regions. We then discusses the importance of tools and standardizing methods for assessment and management purposes, in the context of international environmental policies and marine litter strategies. | acceptedVersion
Afficher plus [+] Moins [-]Different stories told by small and large microplastics in sediment - first report of microplastic concentrations in an urban recipient in Norway Texte intégral
2019
Haave, Marte | Lorenz, Claudia | Primpke, Sebastian | Gerdts, Gunnar
Different stories told by small and large microplastics in sediment - first report of microplastic concentrations in an urban recipient in Norway Texte intégral
2019
Haave, Marte | Lorenz, Claudia | Primpke, Sebastian | Gerdts, Gunnar
Microplastics (MP) in sediments from discharge sites for wastewater and deposition sites in deep regions in an urban fjord in Norway were extracted by density separation in a Microplastic Sediment Separator with ZnCl2. Particles (>11 μm) were identified using FTIR. Twenty different polymer types were identified, at concentrations from 12,000 to 200,000 particles kg−1 dw. Over 95% of the MP were smaller than 100 μm. High deposition of small MP agreed with known areas for organic deposition. Polyurethane acrylate resins dominated the small MP while polyamide fibers dominated the larger MP. Particles >500 μm showed different maximum concentrations and spatial distribution from the smaller particles. This study is the first to report concentration ranges of identified plastic particles from a Norwegian fjord, down to sizes below the limit of visual identification. The results provides a baseline for future comparison, and point at relevant sizes for environmental risk assessments.
Afficher plus [+] Moins [-]Different stories told by small and large microplastics in sediment - first report of microplastic concentrations in an urban recipient in Norway Texte intégral
2019
Haave, Marte | Lorenz, Claudia | Primpke, Sebastian | Gerdts, Gunnar
Microplastics (MP) in sediments from discharge sites for wastewater and deposition sites in deep regions in an urban fjord in Norway were extracted by density separation in a Microplastic Sediment Separator with ZnCl2. Particles (>11 μm) were identified using FTIR. Twenty different polymer types were identified, at concentrations from 12,000 to 200,000 particles kg−1 dw. Over 95% of the MP were smaller than 100 μm. High deposition of small MP agreed with known areas for organic deposition. Polyurethane acrylate resins dominated the small MP while polyamide fibers dominated the larger MP. Particles >500 μm showed different maximum concentrations and spatial distribution from the smaller particles. This study is the first to report concentration ranges of identified plastic particles from a Norwegian fjord, down to sizes below the limit of visual identification. The results provides a baseline for future comparison, and point at relevant sizes for environmental risk assessments.
Afficher plus [+] Moins [-]Policy options to achieve culturally-aware and environmentally-sustainable tourism in Fiji Texte intégral
2019
Tyllianakis, Emmanouil | Grilli, Gaetano | Gibson, Dawn | Ferrini, Silvia | Conejo-Watt, Heather | Luisetti, Tiziana
Policy options to achieve culturally-aware and environmentally-sustainable tourism in Fiji Texte intégral
2019
Tyllianakis, Emmanouil | Grilli, Gaetano | Gibson, Dawn | Ferrini, Silvia | Conejo-Watt, Heather | Luisetti, Tiziana
Increased visitation rates are expected to further impact ecosystems and local communities depending on them to generate income from tourism. We measure how different sustainable tourism management options of such areas in ways that respect the concept of vanua, the Fijian understanding of the connectiveness of the natural environment, humans and traditions, are perceived by a representative sample of potential visitors of the UK population. We then consider some plausible management options and how these may impact welfare. Results show that prospective UK respondents are willing to donate approximately £73 for a management option that enforces medium restrictions by local communities to enter coastal and marine areas in Fiji, so that vanua is respected. A management option that instead denies access to local communities is not seen favourably by prospective UK visitors to Fiji. In terms of time preference, UK respondents, in particular those with previous experiences of tropical areas, prefer environmental projects that restore and protect coastal and marine ecosystems to be completed as soon as possible. Our findings seem to support the introduction of more sustainable and community-based management practices in Fiji as they appear to increase welfare of visitors respecting local traditions and customs, as long as some access is provided to tourists. Donations from tourists or a change in tourism management from a traditional to a more sustainable practice may support the sustainable development of the local coastal communities in Fiji.
Afficher plus [+] Moins [-]Policy options to achieve culturally - aware and environmentally - sustainable tourism in Fiji Texte intégral
2019
Tyllianakis, Emmanouil | Grilli, Gaetano | Gibson, Dawn | Ferrini, Silvia | Conejo-Watt, Heather | Luisetti, Tiziana
Increased visitation rates are expected to further impact ecosystems and local communities depending on them to generate income from tourism. We measure how different sustainable tourism management options of such areas in ways that respect the concept of vanua, the Fijian understanding of the connectiveness of the natural environment, humans and traditions, are perceived by a representative sample of potential visitors of the UK population. We then consider some plausible management options and how these may impact welfare. Results show that prospective UK respondents are willing to donate approximately £73 for a management option that enforces medium restrictions by local communities to enter coastal and marine areas in Fiji, so that vanua is respected. A management option that instead denies access to local communities is not seen favourably by prospective UK visitors to Fiji. In terms of time preference, UK respondents, in particular those with previous experiences of tropical areas, prefer environmental projects that restore and protect coastal and marine ecosystems to be completed as soon as possible. Our findings seem to support the introduction of more sustainable and community-based management practices in Fiji as they appear to increase welfare of visitors respecting local traditions and customs, as long as some access is provided to tourists. Donations from tourists or a change in tourism management from a traditional to a more sustainable practice may support the sustainable development of the local coastal communities in Fiji.
Afficher plus [+] Moins [-]Spatio-temporal monitoring of coastal floating marine debris in the Balearic Islands from sea-cleaning boats Texte intégral
2019
Compa, Montserrat | March, David | Deudero, Salud
Spatio-temporal monitoring of coastal floating marine debris in the Balearic Islands from sea-cleaning boats Texte intégral
2019
Compa, Montserrat | March, David | Deudero, Salud
Mismanaged waste is accumulating at an alarming rate in the marine environment. Its presence has caused local authorities in the Balearic Islands to develop a coastal sea-cleaning boat service covering the region, identifying the floating marine debris, and removing it from the coastal areas. This study considered daily monitoring from May to October spanning from 2005 to 2015. Plastic marine debris composed over 54% of all floating marine debris removed daily across the Balearic Islands. The spatio-temporal patterns indicate a heterogeneous distribution of plastic in the coastal areas, with higher concentrations in the north-western and south-eastern regions of the islands and debris peaking during the month of August. Furthermore, floating marine debris was more easily collected during calm seas as well as using an integrated monitoring approach to facilitate its removal. Overall, sea-cleaning boats are highly effective in removing coastal floating marine debris.
Afficher plus [+] Moins [-]Spatio-temporal monitoring of coastal floating marine debris in the Balearic Islands from sea-cleaning boats Texte intégral
2019
Compa, Montserrat | March, David | Deudero, Salud
Mismanaged waste is accumulating at an alarming rate in the marine environment. Its presence has caused local authorities in the Balearic Islands to develop a coastal sea-cleaning boat service covering the region, identifying the floating marine debris, and removing it from the coastal areas. This study considered daily monitoring from May to October spanning from 2005 to 2015. Plastic marine debris composed over 54% of all floating marine debris removed daily across the Balearic Islands. The spatio-temporal patterns indicate a heterogeneous distribution of plastic in the coastal areas, with higher concentrations in the north-western and south-eastern regions of the islands and debris peaking during the month of August. Furthermore, floating marine debris was more easily collected during calm seas as well as using an integrated monitoring approach to facilitate its removal. Overall, sea-cleaning boats are highly effective in removing coastal floating marine debris.
Afficher plus [+] Moins [-]On the use of random walk schemes in oil spill modelling Texte intégral
2019
Nordam, Tor | Nepstad, Raymond | Litzler, Emma | Röhrs, Johannes
On the use of random walk schemes in oil spill modelling Texte intégral
2019
Nordam, Tor | Nepstad, Raymond | Litzler, Emma | Röhrs, Johannes
In oil spill models, vertical mixing due to turbulence is commonly modelled by random walk. If the eddy diffusivity varies with depth, failing to take the derivative of the diffusivity into account in the random walk scheme will lead to incorrect results. Depending on the diffusivity profile, the result may be either over- or underprediction of the amount of surfaced oil. The importance of using consistent random walk schemes has been known for decades in, e.g., the plankton modelling community. However, it appears not to be common knowledge in the oil spill community, with inconsistent random walk schemes appearing even in recent publications. We demonstrate and quantify the error due to inconsistent random walk, using a simplified oil spill model, and two different diffusivity profiles. In the two cases considered, a commonly used inconsistent scheme predicts respectively 58% and 176% the amount of surface oil, compared to a consistent scheme.
Afficher plus [+] Moins [-]On the use of random walk schemes in oil spill modelling Texte intégral
2019
Nordam, Tor | Nepstad, Raymond | Litzler, Emma | Röhrs, Johannes
In oil spill models, vertical mixing due to turbulence is commonly modelled by random walk. If the eddy diffusivity varies with depth, failing to take the derivative of the diffusivity into account in the random walk scheme will lead to incorrect results. Depending on the diffusivity profile, the result may be either over- or underprediction of the amount of surfaced oil. The importance of using consistent random walk schemes has been known for decades in, e.g., the plankton modelling community. However, it appears not to be common knowledge in the oil spill community, with inconsistent random walk schemes appearing even in recent publications. We demonstrate and quantify the error due to inconsistent random walk, using a simplified oil spill model, and two different diffusivity profiles. In the two cases considered, a commonly used inconsistent scheme predicts respectively 54% and 202% the amount of surface oil, compared to a consistent scheme. | publishedVersion
Afficher plus [+] Moins [-]Baseline concentrations of mercury species within sediments from Qatar's coastal marine zone Texte intégral
2019
Ḥasan, Ḥasan | Elezz, Ahmed Abou | Abuasali, Mazen | AlSaadi, Hamood
Baseline concentrations of mercury species within sediments from Qatar's coastal marine zone Texte intégral
2019
Ḥasan, Ḥasan | Elezz, Ahmed Abou | Abuasali, Mazen | AlSaadi, Hamood
Baseline concentration of total mercury (THg), organic extractable mercury and methylmercury (CH₃Hg) concentrations in sediments from the northeastern, eastern and southeastern parts of the Arabian Gulf were assessed. Surface sediments were collected from eleven stations from the coastal waters of Qatar. All analyses were performed on homogenised samples. Total mercury analysis was performed by Cold Vapour Atomic Absorption Spectrometry (CVAAS), and methylmercury was analysed by Cold Vapour Atomic Fluorescence spectrometry (CVAFS) after aqueous phase ethylation of the extracted samples. Total mercury (THg) in sediments varied from 8.0 μg/kg to 34.3 μg/kg. Methylmercury was detected in all stations and ranged from 1.46 μg/kg to 3.10 μg/kg accounting for 5.4% to 18.4% of total mercury. Total organic carbon (TOC) ranged from 0.16 to 0.72%, while Organic extractable mercury ranged from 1.55 μg/kg to 13.3 μg/kg. Analysis, the grain size within these sediments, was carried out previously paving the way for studying the influence of these parameters on the sedimentary mercury concentration. Speciation was also assessed, as were relations between the measured mercury fractions.
Afficher plus [+] Moins [-]Baseline concentrations of mercury species within sediments from Qatar's coastal marine zone Texte intégral
2019
Hassan, Hassan | Abou Elezz, Ahmed | Abuasali, Mazen | AlSaadi, Hamood
Baseline concentration of total mercury (THg), organic extractable mercury and methylmercury (CH3Hg) concentrations in sediments from the northeastern, eastern and southeastern parts of the Arabian Gulf were assessed. Surface sediments were collected from eleven stations from the coastal waters of Qatar. All analyses were performed on homogenised samples. Total mercury analysis was performed by Cold Vapour Atomic Absorption Spectrometry (CVAAS), and methylmercury was analysed by Cold Vapour Atomic Fluorescence spectrometry (CVAFS) after aqueous phase ethylation of the extracted samples. Total mercury (THg) in sediments varied from 8.0 μg/kg to 34.3 μg/kg. Methylmercury was detected in all stations and ranged from 1.46 μg/kg to 3.10 μg/kg accounting for 5.4% to 18.4% of total mercury. Total organic carbon (TOC) ranged from 0.16 to 0.72%, while Organic extractable mercury ranged from 1.55 μg/kg to 13.3 μg/kg. Analysis, the grain size within these sediments, was carried out previously paving the way for studying the influence of these parameters on the sedimentary mercury concentration. Speciation was also assessed, as were relations between the measured mercury fractions.
Afficher plus [+] Moins [-]Benthic community status and mobilization of Ni, Cu and Co at abandoned sea deposits for mine tailings in SW Norway Texte intégral
2019
Schaanning, Morten Thorne | Trannum, Hilde Cecilie | Øxnevad, Sigurd | Ndungu, Kuria
Benthic community status and mobilization of Ni, Cu and Co at abandoned sea deposits for mine tailings in SW Norway Texte intégral
2019
Schaanning, Morten Thorne | Trannum, Hilde Cecilie | Øxnevad, Sigurd | Ndungu, Kuria
During 1960–94 tailings from an ilmenite mine in southwest Norway were placed in sea deposits in a sheltered fjord and a more exposed coastal basin. In 2015 both deposit sites were sampled to assess the state of metal contamination and macrobenthic communities 20–30 years after deposition was ended. The results showed that nickel and copper still exceeded environmental quality standards in sediment and pore water from the 0–1 cm layer, and fluxes of nickel, copper and cobalt to the overlying water was high compared to adjacent reference stations. Fauna communities were classified as good, but moderate disturbance was recorded along an environmental gradient defined by depth and tailings-induced parameters such as particle size and copper. The results were interpreted in terms of current discharges, biological sediment reworking and near-surface leaching of metal sulphides. No evidence was found for recycling of metals from tailings buried below the bioturbated surface layer.
Afficher plus [+] Moins [-]Benthic community status and mobilization of Ni, Cu and Co at abandoned sea deposits for mine tailings in SW Norway Texte intégral
2019
Schaanning, Morten Thorne | Trannum, Hilde Cecilie | Øxnevad, Sigurd | Ndungu, Kuria
During 1960–94 tailings from an ilmenite mine in southwest Norway were placed in sea deposits in a sheltered fjord and a more exposed coastal basin. In 2015 both deposit sites were sampled to assess the state of metal contamination and macrobenthic communities 20–30 years after deposition was ended. The results showed that nickel and copper still exceeded environmental quality standards in sediment and pore water from the 0–1 cm layer, and fluxes of nickel, copper and cobalt to the overlying water was high compared to adjacent reference stations. Fauna communities were classified as good, but moderate disturbance was recorded along an environmental gradient defined by depth and tailings-induced parameters such as particle size and copper. The results were interpreted in terms of current discharges, biological sediment reworking and near-surface leaching of metal sulphides. No evidence was found for recycling of metals from tailings buried below the bioturbated surface layer. | publishedVersion
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