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Bayesian spatial modeling of cetacean sightings during a seismic acquisition survey 全文
2016
Vilela, Raul | Pena, Ursula | Esteban, Ruth | Koemans, Robin
A visual monitoring of marine mammals was carried out during a seismic acquisition survey performed in waters south of Portugal with the aim of assessing the likelihood of encountering Mysticeti species in this region as well as to determine the impact of the seismic activity upon encounter.Sightings and effort data were assembled with a range of environmental variables at different lags, and a Bayesian site-occupancy modeling approach was used to develop prediction maps and evaluate how species-specific habitat conditions evolved throughout the presence or not of seismic activity.No statistical evidence of a decrease in the sighting rates of Mysticeti by comparison to source activity was found. Indeed, it was found how Mysticeti distribution during the survey period was driven solely by environmental variables.Although further research is needed, possible explanations may include anthropogenic noise habituation and zone of seismic activity coincident with a naturally low density area.
显示更多 [+] 显示较少 [-]Environmental effects of the Deepwater Horizon oil spill: A review 全文
2016
Beyer, Jonny | Trannum, Hilde C. | Bakke, Torgeir | Hodson, Peter V. | Collier, Tracy K.
Environmental effects of the Deepwater Horizon oil spill: A review 全文
2016
Beyer, Jonny | Trannum, Hilde C. | Bakke, Torgeir | Hodson, Peter V. | Collier, Tracy K.
The Deepwater Horizon oil spill constituted an ecosystem-level injury in the northern Gulf of Mexico. Much oil spread at 1100–1300m depth, contaminating and affecting deepwater habitats. Factors such as oil-biodegradation, ocean currents and response measures (dispersants, burning) reduced coastal oiling. Still, >2100km of shoreline and many coastal habitats were affected. Research demonstrates that oiling caused a wide range of biological effects, although worst-case impact scenarios did not materialize. Biomarkers in individual organisms were more informative about oiling stress than population and community indices. Salt marshes and seabird populations were hard hit, but were also quite resilient to oiling effects. Monitoring demonstrated little contamination of seafood. Certain impacts are still understudied, such as effects on seagrass communities. Concerns of long-term impacts remain for large fish species, deep-sea corals, sea turtles and cetaceans. These species and their habitats should continue to receive attention (monitoring and research) for years to come.
显示更多 [+] 显示较少 [-]Environmental effects of the Deepwater Horizon oil spill: A review 全文
2016
Beyer, Jonny | Trannum, Hilde C. | Bakke, Torgeir | Hodson, Peter V. | Collier, Tracy K.
The Deepwater Horizon oil spill constituted an ecosystem-level injury in the northern Gulf of Mexico. Much oil spread at 1100–1300 m depth, contaminating and affecting deepwater habitats. Factors such as oil-biodegradation, ocean currents and response measures (dispersants, burning) reduced coastal oiling. Still, > 2100 km of shoreline and many coastal habitats were affected. Research demonstrates that oiling caused a wide range of biological effects, although worst-case impact scenarios did not materialize. Biomarkers in individual organisms were more informative about oiling stress than population and community indices. Salt marshes and seabird populations were hard hit, but were also quite resilient to oiling effects. Monitoring demonstrated little contamination of seafood. Certain impacts are still understudied, such as effects on seagrass communities. Concerns of long-term impacts remain for large fish species, deep-sea corals, sea turtles and cetaceans. These species and their habitats should continue to receive attention (monitoring and research) for years to come. | acceptedVersion
显示更多 [+] 显示较少 [-]Percentage of microbeads in pelagic microplastics within Japanese coastal waters 全文
2016
Isobe, Atsuhiko
To compare the quantity of microbeads with the quantity of pelagic microplastics potentially degraded in the marine environment, samples were collected in coastal waters of Japan using neuston nets. Pelagic spherical microbeads were collected in the size range below 0.8mm at 9 of the 26 stations surveyed. The number of pelagic microbeads smaller than 0.8mm accounted for 9.7% of all microplastics collected at these 9 stations. This relatively large percentage results from a decrease in the abundance of microplastics smaller than 0.8mm in the upper ocean, as well as the regular loading of new microbeads from land areas, in this size range. In general, microbeads in personal care and cosmetic products are not always spherical, but rather are often a variety of irregular shapes. It is thus likely that this percentage is a conservative estimate, because of the irregular shapes of the remaining pelagic microbeads.
显示更多 [+] 显示较少 [-]Fishes as indicators of untreated sewage contamination in a Mexican coastal lagoon 全文
2016
Aguilar-Betancourt, Consuelo M. | González Sansón, Gaspar | Kidd, Karen A. | Munkittrick, Kelly R. | Curry, R Allen | Kosonoy-Aceves, Daniel | Lucano-Ramírez, Gabriela | Ruiz-Ramírez, Salvador | Flores-Ortega, Juan R.
Lagoons are important nursery habitats for fishes but are often sites of intense human activity including wastewater discharges. The goal of this research was to compare stable nitrogen (δ15N) and carbon (δ13C) isotopes, total mercury (THg) and other metal levels in four selected fish species among sites with different levels of untreated sewage discharge inside Barra de Navidad coastal lagoon in the Mexican Pacific. Three species from sites heavily impacted by sewage showed higher δ15N and δ13C compared to those from non-impacted sites. In addition, the highest concentrations of THg were present in fish of two species (Sciades guatemalensis and Diapterus brevirostris) collected at the two most impacted sites, and exceeded the 0.2μg/g ww threshold believed to be protective of adult and juvenile fish. No individuals of Achirus mazatlanus and Mugil curema exceeded this threshold, and liver somatic index and condition did not distinguish high from low impacted sites for all species. In general, the metal levels differed among species but not sites, and were lower than what has been measured in fishes elsewhere. The study also provides the first information on several fish species for coastal areas of Mexico, suggests that THg and isotopes can distinguish sewage-impacted sites, and can serve as a baseline for future studies.
显示更多 [+] 显示较少 [-]Bioaccumulation of trace element concentrations in common dolphins (Delphinus delphis) from Portugal 全文
2016
Monteiro, Sílvia S. | Pereira, Andreia T. | Costa, Élia | Torres, Jordi | Oliveira, Isabel | Bastos-Santos, Jorge | Araujo, Helder | Ferreira, Marisa | Vingada, José | Eira, Catarina
The common dolphin (Delphinus delphis) is one of the most abundant species in Atlantic Iberia, representing a potentially important tool to assess the bioaccumulation of trace elements in the Iberian marine ecosystem. Nine elements (As, Cd, Cu, Hg, Mn, Ni, Pb, Se and Zn) were evaluated in 36 dolphins stranded in continental Portugal. Dolphins had increasing Hg concentrations (16.72μg·g−1 ww, liver) compared with previous studies in Atlantic Iberia, whereas Cd concentrations (2.26μg·g−1 ww, kidney) fell within reported ranges. The concentrations of some trace elements (including Cd and Hg) presented positive relationships with dolphin length, presence of parasites and gross pathologies. Common dolphins may help biomonitoring more offshore Atlantic Iberian areas in future studies, which would otherwise be difficult to assess.
显示更多 [+] 显示较少 [-]Occurrence and distribution of synthetic musks and organic UV filters from riverine and coastal sediments in the Pearl River estuary of China 全文
2016
Huang, Weixia | Xie, Zhiyong | Yan, Wen | Mi, Wenying | Xu, Weihai
This study reports the occurrence and distribution of synthetic musks (SMs) and organic UV filters (UVFs) in sediment samples collected in 8 riverine runoffs from the Pearl River and Pearl River estuary (PRE). Here, 6 of the 8 target compounds were detected in all sediments with concentrations ranging from 0.35ngg−1 to 456ngg−1. Higher concentrations of SMs and UVFs were evident in the eastern outlets compared to the western suggesting greater input of these contaminants from the Pearl River Delta (PRD) region. All the compounds showed a decreasing trend toward the seaward side which confirming that riverine runoff was the most important source of SMs and UVFs to the coastal environment. Notably, high levels of SMs and UVFs were detected in two fishing harbors in the PRE area. In comparison to UVFs, the SM compounds exhibited a significant correlation with TOC content in the sediments.
显示更多 [+] 显示较少 [-]Radiological maps in beach sands along some coastal regions of Turkey 全文
2016
Kucukomeroglu, B. | Karadeniz, A. | Damla, N. | Yesilkanat, C.M. | Cevik, U.
In the present research, the gamma-emitting radionuclides in beach sands along the coastal regions of the Ordu, Giresun and Trabzon provinces, Turkey have been determined. The natural and anthropogenic radionuclide concentrations of the samples have been measured employing a germanium (HPGe) detector with high resolution and purity. The activity for 238U, 232Th, 40K and 137Cs of the samples were found to vary in the range from below detection limit (BDL) to 65Bq·kg−1, from BDL to 28Bq·kg−1, from 9 to 1936Bq·kg−1 and from BDL to 22Bq·kg−1, respectively. The activity concentrations were compared with those in the literature. The associated radiological hazard indices were estimated, and were compared to the internationally recommended values. The radiological map of beach sand in the surveyed area was imaged. The data presented in the study are crucial since they constitute a baseline for the radiological mapping of the region in the future.
显示更多 [+] 显示较少 [-]Measures for environmental conservation in enclosed coastal seas 全文
2016
Tomita, Akio | Nakura, Yoshio | Ishikawa, Takuya
With putting a focus on the balance among the nutrient salts such as nitrogen and phosphorus, the Ministry of the Environment (MOE) developed the Action Plan for Healthy Material Circulation in Ocean (just called the Healthy Plan). The plan aims to facilitate the healthy and smooth circulation of the nutrients with an integrated management over land and sea as a package in respective sea areas. The Healthy Plan is now in a pilot phase and is to be implemented for some selected model regions.Meanwhile, devastating tsunamis caused by the Great East Japan Earthquake on March 11th, 2011 severely damaged the natural environments in the affected regions. In the affected bays, seaweed beds and spawning grounds disappeared in a blink. MOE has launched on the recovery activities of Zostera (eelgrass) beds, using the concepts and the methods used in the “Sato-umi Creation” activity which is a purposeful environmental recovery project.
显示更多 [+] 显示较少 [-]Temporal and spatial distribution of semicarbazide in western Laizhou Bay 全文
2016
Tian, Xiuhui | Xu, Yingjiang | Song, Xiukai | Gong, Xianghong | Liu, Yihao | Zhou, Quanli | Wang, Zhongquan | Xia, Chuanhai
Semicarbazide (SEM), an industrial raw material and the marker residue of nitrofurazone as a veterinary drug, has become a new type of marine pollutant. A standard method (ultra-performance liquid chromatography–tandem mass spectrometry, UPLC–MS/MS) was used to analyze SEM in seawater, sediment, and shellfish. A series of sections and stations were set up in radical distribution in western Laizhou Bay, with six voyages and 150 monitoring samples. The concentrations of SEM in seawater and shellfish were 10−11 and 10−10kg/L, respectively, and no SEM was detected in the sediment. Distribution characteristics at each state, temporal and spatial trends, multivariate analyses, and the causes were analyzed to assess the pollution level, which aimed to offer a database for drafting the national baseline values of SEM in seawater and sediment in future. The data obtained could be used for integrated watershed management of marine environment and economic activities for constructing a blue economic zone of Shandong Peninsula in China.
显示更多 [+] 显示较少 [-]Succession in an intertidal benthic community affected by untreated sewage effluent: A case of study in the SW Atlantic shore 全文
2016
Becherucci, M.E. | Llanos, E.N. | Garaffo, G.V. | Vallarino, E.A.
A study of benthic succession related with sewage pollution was conducted in a warm-temperate coastal area of Mar del Plata city, Argentina. The effect of nutrient enrichment and starting period of the succession was tested after cleared space in the intertidal rocky shore benthic community. The time of recovery after a disturbance in enriched sites was considerably lower (20–29weeks) than in non-enriched sites based on the diatom Berkeleya sp. and the polychaete Boccardia proboscidea developed in the early succession stage, and Brachidontes rodriguezii or B. proboscidea occurring with Polysiphonia sp., Petalonia fascia and Ulva spp. developed in the late succession stage of the enriched sites. The very low time at which the community recovered in the enriched environments turned out to be one of the assets of the present study and this parameter can be used as a quick indicator of sewage pollution in the area.
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