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Opportunistic detection of anthropogenic micro debris in harbor seal (Phoca vitulina vitulina) and gray seal (Halichoerus grypus atlantica) fecal samples from haul-outs in southeastern Massachusetts, USA Full text
2019
Hudak, Christine A. | Sette, Lisa
Anthropogenic micro debris in the marine environment is a growing concern worldwide, affecting multiple trophic levels, from primary consumers such as zooplankton, to meso- and apex predators like marine mammals and marine birds. In 2016–2017, during the processing of harbor seal (Phoca vitulina vitulina) and gray seal (Halichoerus grypus atlantica) fecal samples for fish otoliths and organic hard parts as part of a prey study, anthropogenic micro debris (>500 μm) was detected in 6% (n = 2/32) of harbor seal and 1% (n = 2/129) of gray seal samples. Spectral analysis identified the fragments as cellophane, alkyd resin and poly(ethylene:propylene:diene) (EPDM) rubber. These results show the potential indirect ingestion of micro debris, which can impact the health and welfare of marine wildlife. This is the first report of micro debris presence in wild populations of phocid seals for the northwestern Atlantic.
Show more [+] Less [-]Assessment of local and regional strategies to control bacteria levels at beaches with consideration of impacts from climate change Full text
2019
Barreras, Henry | Kelly, Elizabeth A. | Kumar, Naresh | Solo-Gabriele, Helena M.
The objective of this study was to evaluate relationships between local factors (beach geomorphology and management) and regional factors (infrastructure improvements and temperature changes) against levels of fecal indicator bacteria (FIB) at recreational beaches. Data were evaluated for 17 beaches located in Monroe County, Florida (Florida Keys), USA, including an assessment of sanitary infrastructure improvements using equivalent dwelling unit (EDU) connections. Results show that elevated FIB levels were associated with beach geomorphologies characterized by impeded flow and by beaches with lax management policies. The decrease in EDUs not connected coincided with a decrease in the fraction of days when bacteria levels were out of compliance. Multivariate factor analysis also identified beach management practices (presence of homeless and concession stands) as being associated with elevated FIB. Overall, results suggest that communities can utilize beach management strategies and infrastructure improvements to overcome the negative water quality impacts anticipated with climate change.
Show more [+] Less [-]Composition variations and spatiotemporal dynamics of dissolved organic matters during the occurrence of green tide (Ulva prolifera blooms) in the Southern Yellow Sea, China Full text
2019
Li, Xiuzhu | Li, Conghe | Bai, Ying | Shi, Xiaoyong | Su, Rongguo
Seawater samples were collected from April 6 to September 6, 2017 in the Southern Yellow Sea, China where green tides often occurred, and analyzed for nutrients, dissolved organic carbon (DOC), and fluorescent dissolved organic matter (FDOM). The DOC concentrations increased significantly in the green tide areas by approximately 1.2 times compared to those in the non-green tide areas. From the large-scale outbreak to the complete dissipation of the green tide, the fluorescence intensities of the four FDOM fluorescent components identified in the green tide areas were significantly higher than those in the non-green tide areas. During the extinction period, the fluorescence intensities of the three humus-like components and one protein-like component were approximately 1.8 and 1.3 times higher than those in the non-green tide areas, respectively. These findings suggested that the outbreak of green tide could release DOM into water and affect the biogeochemical cycle in green tide regions.
Show more [+] Less [-]Polybrominated diphenyl ethers and alternative halogenated flame retardants in mollusks from the Chinese Bohai Sea: Levels and interspecific differences Full text
2019
Fu, Lingfang | Pei, Jie | Zhang, Yuyu | Cheng, Xiaogu | Long, Shenxing | Zeng, Lixi
Polybrominated diphenyl ethers (PBDEs) and alternative halogenated flame retardants (AHFRs) were measured in eleven mollusk species collected from the Chinese Bohai Sea. PBDEs and AHFRs were detected in all species, and their average total concentrations were in the range of 22.5–355 and 10.0–84.3 ng/g lipid weight, respectively. Decabromodiphenyl ether (BDE-209) and decabromodiphenylethane (DBDPE) were the dominant halogenated flame retardants (HFRs), contributing 22.5% to 73.6% and 3.1% to 38.3% of the total HFRs, respectively. The levels of PBDEs and AHFRs were moderate to high from a global perspective. Interspecific differences in the accumulation of PBDEs and AHFRs were characterized by heat map and cluster analysis. Composition profile differences were also observed, with higher proportions of AHFRs in gastropods than in bivalves. These species-specific differences in concentrations and profiles in mollusks were attributed to different species traits, including feeding habit, trophic level, and metabolic potential.
Show more [+] Less [-]First record of debris ingestion by the shorebird American Oystercatcher (Haematopus palliatus) on the Southern coast of Brazil Full text
2019
Rossi, Liana Chesini | Scherer, Angelo Luís | Petry, Maria Virginia
Plastic has become abundant in the oceans and proved to be a threat to marine and coastal fauna. In this study, we present the first record of synthetic debris ingested by the shorebird American Oystercatcher (Haematopus palliatus) in Brazil. We collected 24 stomach contents from October 2007 to October 2015 and 58% were juveniles. Synthetic materials were found in 100% of stomachs. Used plastic fragments and plastic pellets were the most frequent items, beige and white were more common colors. Synthetic material may be unintentionally ingested directly through substrate consumption or indirectly through prey consumption. Hence, debris ingestion may be common, representing an impact to coastal birds. Based on our results, we hope to highlight the need for public policies to reduce the disposal of synthetic debris in the oceans and beaches.
Show more [+] Less [-]Biological invasion: Long term monitoring of the macroalgal flora of a major European harbor complex Full text
2019
Verlaque, Marc | Breton, Gérard
The marine macroflora of the ports of Le Havre and Antifer have been studied by citizen scientists since the late 1970s. In addition to analysis of the previous results, the field study was extended from 2010 to 2018. A total of 97 and 62 macroalgae were identified, respectively, including 14 NIS (non-indigenous species), the latter number being certainly an underestimate since microscopic species were not exhaustively sought and given the high number of cryptogenic species encountered. No new primary introduction of NIS for the NE Atlantic has been detected since the late 1970s. The origin of NIS and vector(s) of introduction were investigated. For all NIS, the donor region is the Indo-Pacific. Two likely vectors have been identified: maritime traffic for earlier introductions, and shellfish imports for more recent ones. The role of these ports and maritime traffic in the processes of introduction is discussed.
Show more [+] Less [-]Large debris dumps in the northern South China Sea Full text
2019
Peng, X. | Dasgupta, S. | Zhong, G. | Du, M. | Xu, H. | Chen, M. | Chen, S. | Ta, K. | Li, J.
Knowledge of the abundance, source, and fate of marine debris in the deep sea is largely constrained thus far. Here, we report the existence of large deep-sea debris dumps that have not been reported before on the seafloor worldwide. Marine debris remarkably accumulated at ~1700–1800 m in the tributary submarine canyons of the Xisha Trough, northern South China Sea (SCS). Although marine debris in Xisha Trough is patchy, the debris abundance was as high as 36,818 and 51,929 items/km² at locations SY78 and SY82, respectively, which is one order of magnitude higher than that in other submarine canyons. We propose that most of the debris came from fishery and navigation activities, as indicated by the categories of debris collected from the seafloor dumps. Seasonal surface ocean currents of the SCS and geomorphology of submarine canyons possibly influence the movement of the debris from coasts to the deep seafloor.
Show more [+] Less [-]Ingestion of macroplastic debris by the common dolphinfish (Coryphaena hippurus) in the Western Equatorial Atlantic Full text
2019
Menezes, Rafael | da Cunha-Neto, Manuel Alves | de Mesquita, Grazielly Campos | da Silva, Guelson Batista
We report the occurrence of macroplastic debris in the stomach of a common dolphinfish (Coryphaena hippurus) caught in the Western Equatorial Atlantic. On the deck, we noticed that the fish was remarkably undernourished and decided to remove its stomach for laboratory analysis. A large part of a plastic bowl and a tuna pectoral fin were the only items recorded in the fish stomach. The plastic measured 99.57 cm2 and weighed 12.77 g, likely blocking the digestive tract and reducing food intake by the fish, as supported by signs of starvation. This is the record of the largest plastic debris ingested by a dolphinfish to date. As the source of the plastic container was probably a tuna fishing boat, we suggest strengthening environmental education programs to enhance the awareness of fishermen and mitigate the impacts of plastic pollution on the pelagic ecosystem and associated organisms, such as C. hippurus.
Show more [+] Less [-]Hexadecane biodegradation of high efficiency by bacterial isolates from Santos Basin sediments Full text
2019
Ferrari, Vitor B. | Cesar, Augusto | Cayô, Rodrigo | Choueri, Rodrigo B. | Okamoto, Débora N. | Freitas, Juliana G. | Favero, Mariana | Gales, Ana C. | Niero, Cristina V. | Saia, Flavia T. | de Vasconcellos, Suzan P.
The aim of the study was the investigation of bacterial diversity from sediments collected at Santos Estuarine System, regarding to their abilities for hexadecane biotransformation. Hexadecane is a medium-chain linear alkane, considered as a model molecule for hydrocarbon biodegradation studies. It is a component from aliphatic fraction of crude petroleum, commonly related to environmental contamination by diesel oil. Santos Basin is an area with historical petroleum contamination. In the present work, sediment samples from this area were inoculated in artificial seawater (ASW), containing hexadecane as carbon source. Six bacterial isolates were selected as resistant to hexadecane. Chromatographic results showed biodegradation indexes above 97%. After 48 h of culture, five of them could degrade >80% of the initial hexadecane added. These isolates were characterized by 16S rDNA gene sequencing analysis. The following species were found: Bacillus amyloliquefaciens, Staphylococcus epidermidis, Micrococcus luteus, Nitratireductor aquimarinus, and Bacillus pumilus.
Show more [+] Less [-]Land use-induced change in trophic state of Shenzhen Bay (South China) over the past half-century Full text
2019
Yan, Hongyu | He, Xiufang | Lei, Yuanda | Wang, Yasu | Su, Hong | Jiang, Shijun
Mangroves connect terrestrial and marine ecosystems and are sensitive to environmental change, and the sediments within faithfully record long-term changes in the aquatic environment and supplement the generally short monitoring archives. Here we present a sediment-core record of TN, TP, TOC, and C/N ratios from the Futian mangrove wetland, Shenzhen Bay (South China), and compare with our remote sensing-derived land use change and the nearby seawater monitoring records. Our reconstructed record extends the history of tropic state change back to the Year 1958, supplementing the monitoring activity initiated in 1987. More importantly, the results reveal two distinct periods. The pre-1983 period (Year 1958–1982) is characterized by increased nutrient due to agricultural activities, while the post-1983 period (Year 1983–2014) is marked by reduced TP but relatively stable TN values, during which the simultaneous increase in construction lands and C/N ratios suggests enhanced soil erosion due to the rapid urbanization of Shenzhen City.
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