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Mercury forms in the benthic food web of a temperate coastal lagoon (southern Baltic Sea) 全文
2020
Jędruch, Agnieszka | Bełdowska, Magdalena
The study was conducted in the coastal zone of the southern Baltic. The research material consisted of macrozoobenthos and elements of its diet. The samples were analysed for Hg and its labile and stable forms, using the thermodesorption method. The results showed that the level of total Hg in zoobenthos was associated with dietary preferences and the share of bioavailable Hg in its food. The Hg fractionation in the macrofauna was conditioned by biological features (morphological structure) and environmental parameters (oxygenation, pH) which shape the mobility and assimilation of Hg. The absorption of the most toxic organic Hg in macrofauna was more effective in aerobic conditions, at low primary production and with the limited inflow of organic matter. The trophic transfer of Hg was favoured by the limited biomass of primary producers, and consequently of zoobenthos. An important factor influencing the biomagnification was also the share of labile Hg in macrozoobenthos.
显示更多 [+] 显示较少 [-]Degradation of BDE-47 in mangrove sediments with amendment of extra carbon sources 全文
2020
Pan, Ying | Chen, Juan | Zhou, Haichao | Cheung, S.G. | Tam, Nora F.Y.
Polybrominated diphenyl ethers (PBDEs) are widely detected in coastal wetlands but their remediation is still difficult. In this study, different carbon sources, namely formate, acetate, pyruvate, lactate, succinate, methanol and ethanol, were added to mangrove sediments contaminated with BDE-47, a common PBDE congener, to enhance its degradation. After 2-month incubation, all carbon addition significantly enhanced degradation percentages. The residual BDE-47 percentage significantly correlated with the abundance of total bacteria and Dehalococcoides spp. The addition of methanol, acetate and succinate also achieved significantly higher degradation rates and shorter half-lives than sediments without carbon amendment at the end of 5-month incubation, although degradation percentages were comparable between sediments with and without extra carbon. The degradation pathway based on the profiles of degradation products was also similar among treatments. The results indicated the stimulatory effect of extra carbon sources on BDE-47 degradation in contaminated sediments was carbon- and time-specific.
显示更多 [+] 显示较少 [-]Levels of metals in fish tissues of Liza haematocheila and Lateolabrax japonicus from the Yellow River Delta of China and risk assessment for consumers 全文
2020
Ge, Meng | Liu, Guijian | Liu, Houqi | Liu, Yuan
The Yellow River Delta (YRD) is an important spawning and nursery area for numerous fishes. The concentrations of Fe, Al, Mn, Zn, Ni, Cr, Cu, Co, Pb and Cd in muscle, liver, gills and skin of two broadly distributed commercial fish in the YRD were analyzed. The results demonstrated that liver and gills displayed higher accumulation ability of metals than other tissues, while muscle always accumulated the lowest concentrations of metals. Generally, significant opposite relationships (p < 0.05) were observed between fish size and metals in fish tissues especially in muscles of both fish species which may be explained by the lower feeding rate, stronger detoxification and elimination mechanisms in the bigger individuals. All metals in muscles were well below the proposed toxic limit. Besides, the toxic effects were not expected to occur for the consumption of muscles of studied fish according to the results of human health risk assessment.
显示更多 [+] 显示较少 [-]The impacts of polyethylene terephthalate microplastics (mPETs) on ecosystem functionality in marine sediment 全文
2020
You, Yuxi | Thrush, Simon F. | Hope, Julie A.
The effects of microplastics (MPs) on the ecological functioning in marine sediments is largely unknown. However, coastal marine sediments and their resident communities play critical roles in the transformation of organic matter and the cycling of nutrients that influence both local and global processes. To investigate how microplastics influence ecosystem functions associated with sediment biogeochemistry, large bivalves and microphytobenthos, we conducted a 31-day laboratory experiment. The experiment tested the role of micro-polyethylene terephthalate (mPETs) at five concentrations (0%, 1%, 3%, 6%, and 8% based on wet weight of top 1 cm sediment). Canonical principle of coordinate analysis (CAP) was applied to assess change on the ecosystem functionality with increasing concentrations of mPETs. Our results highlight that stress effects on ecosystem function are the product of the interaction between Macomona liliana, microphytobenthos and mPETs.
显示更多 [+] 显示较少 [-]Model-based reconstruction of the Ulysse-Virginia oil spill, October–November 2018 全文
2020
Liubartseva, S. | Smaoui, M. | Coppini, G. | Gonzalez, G. | Lecci, R. | Cretì, S. | Federico, I.
In response to the oil spill caused by the collision between the Ro-Ro ship Ulysse and CSL Virginia on 7ᵗʰ October 2018, the Lagrangian oil spill model MEDSLIK-II was utilized to predict spill transport and fate. Oil drift was forced by the high-resolution sea circulation provided by CMEMS and the ECMWF wind. Successive model runs were restarted 5 times with the distinct overflight- and satellite-derived observations provided by REMPEC and the Copernicus Sentinel-1 mission. The results were verified based on the ability to predict the first oil-beaching event that happened near Saint-Tropez (France) in the early afternoon of 16ᵗʰ October. Despite the general consistency among the runs, only the last initialization was able to forecast the oil beaching. Stochastic MEDSLIK-II simulations forced by the historical meteo-oceanographic datasets 2014–2018 revealed that the coastlines between Cap Lardier and the Gulf of Saint-Tropez were among the most impacted areas.
显示更多 [+] 显示较少 [-]A field comparison of marine mammal detections via visual, acoustic, and infrared (IR) imaging methods offshore Atlantic Canada 全文
2020
Smith, Heather R. | Zitterbart, Daniel P. | Norris, Thomas F. | Flau, Michael | Ferguson, Elizabeth L. | Jones, Colin G. | Boebel, Olaf | Moulton, Valerie D.
A field comparison of marine mammal detections via visual, acoustic, and infrared (IR) imaging methods offshore Atlantic Canada 全文
2020
Smith, Heather R. | Zitterbart, Daniel P. | Norris, Thomas F. | Flau, Michael | Ferguson, Elizabeth L. | Jones, Colin G. | Boebel, Olaf | Moulton, Valerie D.
Impulsive sounds generated during seismic surveys have elicited behavioral responses in marine mammals and could cause hearing impairment or injury. Mitigating exposure to seismic sound often relies on real-time marine mammal detection. Detection performance is influenced by detection method, environmental conditions, and observer experience. We conducted a field comparison of real-time detections made by marine mammal observers (MMOs), a rotating infrared (IR) camera, and via passive acoustic monitoring (PAM). Data were collected from a 38 m research vessel offshore Atlantic Canada. Our results indicate that overall detection rates increase when complementary methods are used. MMOs and PAM are likely the most effective combination during high seas and precipitation. PAM and IR can be used in darkness. In good visibility, MMOs with IR or PAM should increase detections. Our results illustrate the importance of addressing false positive IR detections, matching system capabilities to sea conditions/species of interest, and employing experienced observers.
显示更多 [+] 显示较少 [-]A field comparison of marine mammal detections via visual, acoustic, and infrared (IR) imaging methods offshore Atlantic Canada 全文
2020
Smith, Heather R. | Zitterbart, Daniel P. | Norris, Thomas F. | Flau, Michael | Ferguson, Elizabeth L. | Jones, Colin G. | Boebel, Olaf | Moulton, Valerie D.
Impulsive sounds generated during seismic surveys have elicited behavioral responses in marine mammals and could cause hearing impairment or injury. Mitigating exposure to seismic sound often relies on real-time marine mammal detection. Detection performance is influenced by detection method, environmental conditions, and observer experience. We conducted a field comparison of real-time detections made by marine mammal observers (MMOs), a rotating infrared (IR) camera, and via passive acoustic monitoring (PAM). Data were collected from a 38 m research vessel offshore Atlantic Canada. Our results indicate that overall detection rates increase when complementary methods are used. MMOs and PAM are likely the most effective combination during high seas and precipitation. PAM and IR can be used in darkness. In good visibility, MMOs with IR or PAM should increase detections. Our results illustrate the importance of addressing false positive IR detections, matching system capabilities to sea conditions/species of interest, and employing experienced observers.
显示更多 [+] 显示较少 [-]The role of coated fertilizer used in paddy fields as a source of microplastics in the marine environment 全文
2020
Katsumi, Naoya | Kusube, Takasei | Nagao, Seiya | Ōkōchi, Hiroshi
Fixed-point and multi-point field survey was conducted to determine the actual contamination of the Japanese coast by microcapsules derived from coated fertilizers. The results indicated that the amount of microcapsules increased during the irrigation season (9423–74,869 pieces/m²) and decreased in the non-irrigation season (77–1471 pieces/m²). Microcapsules accounted for 90% of all microplastics sampled during the irrigation season. The lack of correlation between the area of agricultural land in the watershed and the microcapsule density on the coast suggested that the density of microcapsules on the coast was not only dependent on the total load to the ocean, but also on topographic and meteorological conditions. More than 90% of the microcapsules collected from the shoreline were made of polyethylene. Scanning electron microscopic observation of the surface of the microcapsules revealed that portions of the microcapsules were removed as secondary microplastics in the process of migration to the ocean.
显示更多 [+] 显示较少 [-]Developing interim water quality criteria for emerging chemicals of concern for protecting marine life in the Greater Bay Area of South China 全文
2020
Farzana, Shazia | Ruan, Yuefei | Wang, Qi | Wu, Rongben | Kai, Zhang | Meng, Yan | Leung, Kenneth M.Y. | Lam, Paul K.S.
This study aimed to establish marine water quality criteria (MWQC) for emerging chemicals of concern (ECCs) for protecting aquatic life in the Greater Bay Area (GBA) of South China. Despite the frequent occurrence and elevated concentrations of these ECCs in the GBA, there is a lack of regional MWQC for these contaminants. We screened 21 common ECCs that were classified into the following six groups: (1) new persistent organic contaminants; (2) brominated flame retardants; (3) perfluoroalkyl and polyfluoroalkyl substances; (4) pharmaceutically active compounds (PhACs); (5) plasticizers; and (6) personal care products. Globally, MWQC for PhACs remain largely unavailable despite their increasing occurrence in marine environments. Using an integrative scientific approach, we derived interim MWQC for the GBA with specific protection goals. The approach described herein can be applied for the derivation of MWQC for ECCs and the establishment of guidelines for ecological risk assessment in the GBA and other regions.
显示更多 [+] 显示较少 [-]Remote sensing approach for the estimation of particulate organic carbon in coastal waters based on suspended particulate concentration and particle median size 全文
2020
Wang, Fan | Wang, Yaqi | Chen, Yiyue | Liu, Kunkun
The particulate organic carbon (POC) content retrieved by remote sensors is influenced by the suspended particulate concentration (SPC) and the particle size distribution (PSD). The objective of this study was to provide study case of remote sensing monitoring of non-optical activity substance POC in Hangzhou bay, China. A modified empirical remote sensing algorithm was established based on SPC and median particle size (D₅₀) to describe the influence of PSD variation on remote sensing reflectance (Rᵣₛ). The algorithm was applied to MODIS data to reveal POC spatial and temporal variations. The results show that the accuracy of the remote sensing estimation algorithm, established on the basis of Mie theory, is relatively higher than the empirical model simply based on the statistical correlation between Rᵣₛ and POC. The POC in Hangzhou bay caused by spring and neap tides vary significantly.
显示更多 [+] 显示较少 [-]Quantitative overview of marine debris ingested by marine megafauna 全文
2020
Kuhn, Susanne | van Franeker, Jan Andries
Quantitative overview of marine debris ingested by marine megafauna 全文
2020
Kuhn, Susanne | van Franeker, Jan Andries
This review quantifies plastic interaction in marine biota. Firstly, entanglement and ingestion records for all marine birds, mammals, turtles, fish, and invertebrate species, are summarized from 747 studies. Marine debris affected 914 species through entanglement and/or ingestion. Ingestion was recorded for 701 species, entanglement was documented for 354 species. Secondly, the frequency of occurrence of ingestion per species (Sp-%FO) was extracted for marine birds, mammals and turtles. Thirdly, for seabird species, average numbers of plastics ingested per individual were determined. Highest Sp-%FO and average number of plastics were found in tubenosed seabirds with 41% of all birds analysed having plastics, on average 9.9 particles per bird. The Sp-%FO and average number of ingested particles is lower for most other species. However, for certain species, ingestion rates of litter are reason for serious concern. Standardized methods are crucial for future studies, to generate datasets that allow higher level ecosystem analyses.
显示更多 [+] 显示较少 [-]Quantitative overview of marine debris ingested by marine megafauna
2020
Kühn, Susanne | Franeker, van, Jan Andries
This review quantifies plastic interaction in marine biota. Firstly, entanglement and ingestion records for all marine birds, mammals, turtles, fish, and invertebrate species, are summarized from 747 studies. Marine debris affected 914 species through entanglement and/or ingestion. Ingestion was recorded for 701 species, entanglement was documented for 354 species. Secondly, the frequency of occurrence of ingestion per species (Sp-%FO) was extracted for marine birds, mammals and turtles. Thirdly, for seabird species, average numbers of plastics ingested per individual were determined. Highest Sp-%FO and average number of plastics were found in tubenosed seabirds with 41% of all birds analysed having plastics, on average 9.9 particles per bird. The Sp-%FO and average number of ingested particles is lower for most other species. However, for certain species, ingestion rates of litter are reason for serious concern. Standardized methods are crucial for future studies, to generate datasets that allow higher level ecosystem analyses.
显示更多 [+] 显示较少 [-]Quantitative overview of marine debris ingested by marine megafauna 全文
2020
Kühn, Susanne | van Franeker, Jan Andries
This review quantifies plastic interaction in marine biota. Firstly, entanglement and ingestion records for all marine birds, mammals, turtles, fish, and invertebrate species, are summarized from 747 studies. Marine debris affected 914 species through entanglement and/or ingestion. Ingestion was recorded for 701 species, entanglement was documented for 354 species. Secondly, the frequency of occurrence of ingestion per species (Sp-%FO) was extracted for marine birds, mammals and turtles. Thirdly, for seabird species, average numbers of plastics ingested per individual were determined. Highest Sp-%FO and average number of plastics were found in tubenosed seabirds with 41% of all birds analysed having plastics, on average 9.9 particles per bird. The Sp-%FO and average number of ingested particles is lower for most other species. However, for certain species, ingestion rates of litter are reason for serious concern. Standardized methods are crucial for future studies, to generate datasets that allow higher level ecosystem analyses.
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