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Temporal and interspecific variation in feather mercury in four penguin species from Macquarie Island, Australia
2019
Gilmour, M.E. | Holmes, N.D. | Fleishman, A.B. | Kriwoken, L.K.
We measured mercury (Hg) concentrations in feathers from four penguin species collected on Macquarie Island, Southern Ocean, to 1) establish baseline Hg concentrations; and 2) compare Hg from samples collected in 2002 (“modern”) and from museum specimens collected between 1937 and 1976 (“historic”). Inter-specific differences in feather Hg reflected known differences in habitats and diversity of diets: benthic-foraging Gentoo penguins and Rockhopper penguins that foraged both inshore and offshore had significantly higher feather mercury than the more pelagic, specialist foraging King and Royal penguins. Hg significantly decreased between historic and modern samples in King and Royal penguins. This decrease could be due to changes in either diet, foodwebs, or atmospheric Hg input and sources in the Southern Hemisphere. Because Macquarie Island is home to 2.8 million marine animals, these data may indicate that other species that forage and breed in this region are also exposed to low Hg concentrations in this environment.
Mostrar más [+] Menos [-]Benthic ecological quality assessment of the Bohai Sea, China using marine biotic indices
2019
Ni, Dapeng | Zhang, Zhinan | Liu, Xiaoshou
The coastal ecological environments are heavily affected by anthropogenic activities as well as global climate change. Macrofauna can be used as good indicators for benthic ecological quality status due to its relatively slow movement ability under disturbance and a variety of assessment approaches have been established based on the characteristics of macrofauna. The benthic ecological quality of the Bohai Sea, China, is increasingly threatened by anthropogenic activities. In order to accurately assess the benthic ecological quality status in this region, Shannon-Wiener diversity index, ABC curve, AMBI, M-AMBI and macrofaunal feeding evenness index were used. Results showed that the northern Laizhou Bay and Bohai Bay were under slight disturbance while Liaodong Bay, the central Bohai Sea and Bohai Strait were under moderate disturbance. Overall, the ecological quality indicated by the assessment results of AMBI, Shannon-Wiener diversity index and feeding evenness index were better than that by M-AMBI and the ABC curve.
Mostrar más [+] Menos [-]Suitability of the shallow water hydrothermal system at Ambitle Island (Papua New Guinea) to study the effect of high pCO2 on coral reefs
2019
Pichler, T. | Biscéré, T. | Kinch, J. | Zampighi, M. | Houlbrèque, F. | Rodolfo-Metalpa, R.
Volcanic CO₂ seeps were successfully used to predict coral reef response to ocean acidification, although toxic elements, often characteristic of hydrothermal vents were rarely reported. We measured the physicochemical conditions, seawater carbonate chemistry and trace elements in Tutum Bay, Papua New Guinea. There, intense emission of hydrothermal fluids and CO₂ expose the coral reef to a seawater pHT between 7.6 and 7.7.Arsenic and silica were enriched by up to six times in surface seawater, while bottom concentrations were lower and thus similar to coral reefs worldwide. Manganese, cesium, iron and zinc concentrations fell into the range of other coastal environments. Our measurements suggest that Tutum Bay is a suitable site to study the response of coral reefs to high pCO₂. Considering that arsenic is a common metal in hydrothermal fluids, its characterization should be included in any study that uses volcanic CO₂ seeps as natural laboratories for ocean acidification.
Mostrar más [+] Menos [-]Ballast water sediment management in ports
2019
Maglić, Lovro | Frančić, Vlado | Zec, Damir | David, Matej
In order to estimate the possible effects of existing ballast tank sediment management routine in ports the respective legal framework from different states was examined and the operational modes of selected Adriatic shipyards was analysed. The goal was to determine if the States' administration and ports' management are aware of risks which sediments pose to human health and environment due to possible presence of harmful aquatic organisms and pathogens (HAOP) or high concentrations of heavy metals. The analysis revealed that sediments from ballast tanks after being collected, are subject to the same handling procedure as any other waste material generated during ships' repair and maintenance. In addition, measures preventing sediment drainage into the sea or procedures for analyzing the presence of heavy metals or toxics have not been identified. The paper proposes the procedures ensuring the more advanced level of protection from HAOP and potentially toxic substances from ballast sediment.
Mostrar más [+] Menos [-]Numerical study on the summertime patches of red tide in the adjacent sea of the Changjiang (Yangtze) River Estuary, China
2019
Qu, Dapeng | Yu Huaming, | Sun, Yuchen | Zhao, Yunxia | Wei, Qinsheng | Yu, Haiqing | Kelly, Ryan M. | Yuan, Yeli
High incident rates of red tide have occurred off the coast of the Changjiang (Yangtze) River Estuary in summer, resulting from a magnified population growth discharging substantial nutrient loads into this vicinity. The presence of elevated Chlorophyll-a concentrations (≥36.3 μg/l), low suspended sediment concentrations in surface and mid-layers (<10 mg/l), a strong saline front and surface water temperature gradient, veering surface winds, and a bimodal shape to the Changjiang Diluted Water (CDW) revealed two red tide patches appearing between August 6–13, 2010. Two distinguishable hydrodynamic driving mechanisms, connected to these incidents, are diagnosed. Field observations and numerical simulations determined a red tide patch in the northeastern offshore area is caused by a northeast transport of the CDW truncated by a northwest intrusion of the Taiwan Warm Current (TWC) as winds deviated. Red tide occurrence in the southern nearshore area originated from a plume front where CDW interfaces with the TWC.
Mostrar más [+] Menos [-]Spatiotemporal distributions of halocarbons in the marine boundary air and surface seawater of the Changjiang estuary and its adjacent East China Sea
2019
Yuan, Da | He, Zhen | Yang, Gui-Peng
Spatiotemporal distributions of volatile halogenated organic compounds (VHOCs) were investigated in the marine boundary air and surface seawater of the Changjiang (Yangtze River) estuary and its adjacent East China Sea in two cruises from March 11, 2015 to March 21, 2015 and from July 9, 2015 to July 20, 2015. Results revealed that the concentrations of released chlorofluorocarbons (CFCs) such as CFC-12, CFC-11, and CFC-114 in China decreased, suggesting that limitations set by the Chinese government on CFCs production and consumption have taken effect. Atmospheric concentrations of CFCs were affected by local industrial sources of emission and transport of terrestrial pollutants from coastal areas to varying degrees. Seasonal variations in atmospheric VHOCs were probably due to seasonal differences in prevalent monsoon and biogenic production. In the study periods, the investigated area was an essential source of atmospheric CH3Br and CH3I but was a net sink of CFC-12, CFC-11, and CH3Cl.
Mostrar más [+] Menos [-]Spatiotemporal characterization of metals in small craft harbour sediments in Nova Scotia, Canada
2019
Zhang, Hongling | Walker, Tony R. | Davis, Emily | Ma, Guofeng
Spatiotemporal (2001–2017) characterization of sediment metal concentrations were assessed in 31 small craft harbours (SCHs) in Nova Scotia, Canada by analyzing secondary data from government sediment assessment reports. Surficial sediment samples (n = 576) were collected prior to routine maintenance or constriction dredging activities. Sediment metal concentration ranges were 0.5–62 (As), 0.05–3.8 (Cd), 1–305 (Cr), 0.5–220 (Cu), 0.003–1.85 (Hg), 0.73–583 (Pb) and 5–2300 (Zn) mg/kg (dw), respectively. Most sediment metal concentrations (>56% of samples) were below low effect level and >96% were below high effect level sediment quality guidelines, suggesting limited ecological impairment to marine biota. Despite wide temporal coverage (16 years), large variation in sediment concentrations across SCHs were likely due to regular dredging activities preventing long-term accumulation of contaminants. Spatial distribution and enrichment factor results revealed that Canso was most impacted by metals, followed by Clarks Harbour.
Mostrar más [+] Menos [-]Sources of microplastics pollution in the marine environment: Importance of wastewater treatment plant and coastal landfill
2019
Kazour, Maria | Terki, Sarah | Rabhi, Khalef | Jemaa, Sharif | Khalaf, Gaby | Amara, Rachid
This study investigated the role of a municipal wastewater treatment plant (WWTP) effluent and an abandoned coastal landfill as pathways for microplastics (MPs) input into the marine environment. MPs were first analyzed in raw sewage influent, sludge and effluent samples, and their fate was studied along a distance gradient from the WWTP in three matrices: surface water, sediments and wild mussels. All suspected MPs were characterized according to their polymer nature using micro-Raman spectroscopy. The investigated WWTP had an estimated daily discharge of 227 million MPs. MPs were found in all matrices with a decreasing abundance from the effluent. Strong MPs abundances (higher than those found near the WWTP effluent) were observed in the vicinity of the coastal landfill suggesting its importance as a MPs entry route into the marine coastal environment. Our study supports the idea that blue mussels are a promising sentinel species for MPs (<200 μm).
Mostrar más [+] Menos [-]Port Baseline Biological Surveys and seaweed bioinvasions in port areas: What's the matter in the Adriatic Sea?
2019
Petrocelli, Antonella | Antolić, Boris | Bolognini, Luca | Cecere, Ester | Cvitković, Ivan | Despalatović, Marija | Falace, Annalisa | Finotto, Stefania | Iveša, Ljiljana | Mačić, Vesna | Marini, Mauro | Orlando Bonaca, Martina | Rubino, Fernando | Trabucco, Benedetta | Žuljević, Ante
One of the objectives of the BALMAS project was to conduct Port Baseline Biological Surveys of native and non-indigenous benthic flora in 12 Adriatic ports. Samples of macroalgae growing on vertical artificial substrates were collected in spring and autumn 2014 and/or 2015. A total number of 248 taxa, 152 Rhodophyta, 62 Chlorophyta, and 34 Ochrophyta, were identified. Of these, 13 were non-indigenous seaweeds, mainly filamentous macroalgae, that were probably introduced through hull fouling. Some of these taxa had already been described in the study areas, others were recorded for the first time, a few were no longer detected at sites where they had previously been recorded (e.g. Sargassum muticum). Some other NISS reported for the Adriatic Sea, were not collected at any sampling site (i.e. Caulerpa cylindracea, Codium fragile). Possible reasons for the absence of these species are discussed.
Mostrar más [+] Menos [-]Spatial-temporal variation of heavy metals' sources in the surface sediments of the Yangtze River Estuary
2019
Liu, Ruimin | Guo, Lijia | Men, Cong | Wang, Qingrui | Miao, Yuexi | Shen, Zhenyao
In this study, positive matrix factorization, multilinear engine 2, and geographic information systems were used to characterize the spatial-temporal patterns of sources for nine heavy metals in the surface sediments of the Yangtze River Estuary in different seasons. Results showed that six sources were identified: agricultural pesticide, marine transportation, chemical factory wastewater, metal smelter waste, atmospheric deposition, and agricultural fertilizer. The proportions of sources were similar during the entire year but varied among the seasons. The differences in the proportions of agricultural pesticide between winter and other seasons were greater than 12%. Over 40% of the Cd concentration in most seasons was attributed to atmospheric deposition, while less than 5% in autumn. The impact strength of most sources, except marine transportation and metal smelter waste, decreased from the inner regions to the adjacent sea. The difference in the impact strength of agricultural pesticide was the largest throughout the study area.
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