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1.
Sci Total Environ ; 802: 149807, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34450439

RESUMO

It is expected that by 2050 human population will exceed nine billion leading to increased pressure on marine ecosystems. Therefore, it is conjectured various levels of ecosystem functioning starting from individual to population-level, species distribution, food webs and trophic interaction dynamics will be severely jeopardized in coming decades. Ocean warming and acidification are two prime threats to marine biota, yet studies about their cumulative effect on marine fish and shellfishes are still in its infancy. This review assesses existing information regarding the interactive effects of global environmental factors like warming and acidification in the perspective of marine capture fisheries and aquaculture industry. As climate change continues, distribution pattern of species is likely to be altered which will impact fisheries and fishing patterns. Our work is an attempt to compile the existing literatures in the biological perspective of the above-mentioned stressors and accentuate a clear outline of knowledge in this subject. We reviewed studies deciphering the biological consequences of warming and acidification on fish and shellfishes in the light of a molecule to ecosystem perspective. Here, for the first time impacts of these two global environmental drivers are discussed in a holistic manner taking into account growth, survival, behavioural response, prey predator dynamics, calcification, biomineralization, reproduction, physiology, thermal tolerance, molecular level responses as well as immune system and disease susceptibility. We suggest urgent focus on more robust, long term, comprehensive and ecologically realistic studies that will significantly contribute to the understanding of organism's response to climate change for sustainable capture fisheries and aquaculture.


Assuntos
Ecossistema , Água do Mar , Animais , Mudança Climática , Aquecimento Global , Humanos , Concentração de Íons de Hidrogênio , Oceanos e Mares , Frutos do Mar
2.
Chemosphere ; 286(Pt 1): 131677, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34346336

RESUMO

China is considered to account for nearly a third of all plastic waste discharging from land to the ocean. To overall assess microplastic pollution status in Chinese coastal and marginal seas, this study summarized the abundance and characteristics of microplastics in the seawater, sediments and marine organisms. The results showed that the abundance of microplastics in the seawater of four major seas of China was 0.13-545 items/m³, and microplastic abundance in the sediments from the estuaries was 20-7900 items/kg, which are at middle level or even lower than those detected in other countries. By contrast, severe microplastic pollution was recorded in the estuaries, suggesting that plastic waste and microplastic interception measures should be conducted on the rivers to prevent the input of microplastics. In addition, microplastics were widely detected in marine fishes, mollusks, zooplankton, mammals and birds, which highlights the potential impacts of microplastic pollution on the whole marine ecosystem. Compared to the dry season, higher microplastic abundance was found in the rainy season, revealing that plastic waste recycling should be strengthened before the onset of rainy season. We suggest that all countries respond actively to the ubiquitous microplastic pollution through practical policies and measures to prevent microplastics from further damaging the marine ecosystem.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , China , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Oceanos e Mares , Plásticos , Água do Mar , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
3.
Sci Total Environ ; 806(Pt 1): 150435, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34583070

RESUMO

Human activities have led to an increase in land use change, with effects on the structure and functioning of ecosystems. The impact of contrasting land uses along river basins on the concentration of colored dissolved organic matter (CDOM) reaching the coastal zone, and its relationship with the carbonate system of the adjacent coastal ocean, is poorly known. To understand the relationship between land use change, CDOM and its influence on the carbonate system, two watersheds with contrasting land uses in southern Chile were studied. The samples were collected at eight stations between river and adjacent coastal areas, during three sampling campaigns in the austral summer and spring. Chemical and biological samples were analyzed in the laboratory according to standard protocols. Landsat 8 satellite images of the study area were used for identification and supervised classification using remote sensing tools. The Yaldad River basin showed 82% of native forest and the Colu River basin around 38% of grassland (agriculture). Low total alkalinity (AT) and Dissolved Inorganic Carbon (DIC), but high CDOM proportions were typically observed in freshwater. A higher CDOM and humic-like compounds concentration was observed along the river-coastal ocean continuum in the Yaldad basin, characterized by a predominance of native forests. In contrast, nutrient concentrations, AT and DIC, were higher in the Colu area. Low CaCO3 saturation state (ΩAr < 2) and even undersaturation conditions were observed at the coastal ocean at Yaldad. A strong negative correlation between AT, DIC and ΩAr with CDOM/fDOM, suggested the influence of terrestrial material on the seawater carbon chemistry. Our results provide robust evidence that land uses in river basins can influence CDOM/fDOM proportion and its influence on the carbonate chemistry of the adjacent coastal, with potential implications for the shellfish farming activity in this region.


Assuntos
Ecossistema , Rios , Carbonatos , Água Doce , Humanos , Oceanos e Mares
4.
Sci Total Environ ; 805: 150186, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34818771

RESUMO

The lack of information about plastic pollution in many marine regions hinders firm actions to manage human activities and mitigate their impacts. This study conducted for the first time a quali-quantitative evaluation of floating plastics and their associated biota from coastal and oceanic waters in South Brazil. Plastics were collected using a manta net, and were categorized according to their shape, size, malleability and polymer composition. Multi-marker DNA metabarcoding (16S, and 18S V4 and V9 rRNA regions) was performed to identify prokaryotes and eukaryotes associated to plastics. We found 371 likely plastic particles of several sizes, shapes and polymers, and the average concentration of plastics at the region was 4461 items.km-2 (SD ± 3914). Microplastics (0.5 - 5 mm) were dominant in most sampling stations, with fragments and lines representing the most common shapes. Diverse groups of prokaryotes (20 bacteria phyla) and eukaryotes (41 groups) were associated with plastics. Both the community composition and richness of epiplastic organisms were highly variable between individual plastics but, in general, were not influenced by plastic categories. Organisms with potential pathogenicity (e.g. Vibrio species. and Alexandrium tamarense), as well as potential plastic degraders (e.g. Ralstonia, Pseudomonas, and Alcanivorax species), were found. The information generated here is pivotal to support strategies to prevent the input and mitigate the impacts of plastics and their associated organisms on marine environments.


Assuntos
Plásticos , Poluentes Químicos da Água , Biota , Monitoramento Ambiental , Humanos , Microplásticos , Oceanos e Mares , Poluentes Químicos da Água/análise
5.
Chemosphere ; 287(Pt 1): 131903, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34455125

RESUMO

Microplastics are contaminants of emerging concern - not only environmental, but also to human health. Characterizing them is of fundamental importance to evaluate their potential impacts and target specific actions aiming to reduce potential harming effects. This study extends the exploration of machine learning classification algorithms applied to FTIR spectra of microplastics collected at sea. A comparison of successful classification models was made in order to evaluate prediction performance for 13 classes of polymers. A rigorous methodology was applied using a pipeline scheme to avoid bias in the training and selection phases. The application of an oversampling technique also contributed by compensating unbalanceness in the dataset. The log-loss was used as the minimization function target and to assess performance. In our analysis, Support Vector Machine Classifier provides a good relationship between simplicity and performance, for a fast and useful automatic characterization of microplastics.


Assuntos
Microplásticos , Plásticos , Algoritmos , Monitoramento Ambiental , Humanos , Aprendizado de Máquina , Oceanos e Mares , Espectroscopia de Infravermelho com Transformada de Fourier , Máquina de Vetores de Suporte
6.
Environ Sci Technol ; 55(21): 14445-14456, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34724789

RESUMO

We present a new chemical mechanism for Hg0/HgI/HgII atmospheric cycling, including recent laboratory and computational data, and implement it in the GEOS-Chem global atmospheric chemistry model for comparison to observations. Our mechanism includes the oxidation of Hg0 by Br and OH, subsequent oxidation of HgI by ozone and radicals, respeciation of HgII in aerosols and cloud droplets, and speciated HgII photolysis in the gas and aqueous phases. The tropospheric Hg lifetime against deposition in the model is 5.5 months, consistent with observational constraints. The model reproduces the observed global surface Hg0 concentrations and HgII wet deposition fluxes. Br and OH make comparable contributions to global net oxidation of Hg0 to HgII. Ozone is the principal HgI oxidant, enabling the efficient oxidation of Hg0 to HgII by OH. BrHgIIOH and HgII(OH)2, the initial HgII products of Hg0 oxidation, respeciate in aerosols and clouds to organic and inorganic complexes, and volatilize to photostable forms. Reduction of HgII to Hg0 takes place largely through photolysis of aqueous HgII-organic complexes. 71% of model HgII deposition is to the oceans. Major uncertainties for atmospheric Hg chemistry modeling include Br concentrations, stability and reactions of HgI, and speciation and photoreduction of HgII in aerosols and clouds.


Assuntos
Mercúrio , Aerossóis , Monitoramento Ambiental , Mercúrio/análise , Oceanos e Mares , Oxirredução , Água
7.
Adv Mar Biol ; 90: 51-63, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34728054

RESUMO

Backcasting involves the design of a desirable future that is not simply predicted with forecasts being, instead, proactively aimed at with effective action. So far, all initiatives towards sustainability failed, probably due to lack of investments in the acquisition of knowledge on the structure and the function of natural systems (i.e. biodiversity and ecosystem functioning), and to the reliance on models and estimates based on incomplete data.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Biodiversidade , Oceanos e Mares
8.
Sensors (Basel) ; 21(21)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34770313

RESUMO

Coasts are areas of vitality because they host numerous activities worldwide. Despite their major importance, the knowledge of the main characteristics of the majority of coastal areas (e.g., coastal bathymetry) is still very limited. This is mainly due to the scarcity and lack of accurate measurements or observations, and the sparsity of coastal waters. Moreover, the high cost of performing observations with conventional methods does not allow expansion of the monitoring chain in different coastal areas. In this study, we suggest that the advent of remote sensing data (e.g., Sentinel 2A/B) and high performance computing could open a new perspective to overcome the lack of coastal observations. Indeed, previous research has shown that it is possible to derive large-scale coastal bathymetry from S-2 images. The large S-2 coverage, however, leads to a high computational cost when post-processing the images. Thus, we develop a methodology implemented on a High-Performance cluster (HPC) to derive the bathymetry from S-2 over the globe. In this paper, we describe the conceptualization and implementation of this methodology. Moreover, we will give a general overview of the generated bathymetry map for NA compared with the reference GEBCO global bathymetric product. Finally, we will highlight some hotspots by looking closely to their outputs.


Assuntos
Sistemas de Informação Geográfica , Oceanos e Mares , África do Norte , Monitoramento Ambiental , Oceanografia
9.
Sensors (Basel) ; 21(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34770475

RESUMO

The establishment of maritime safety and security is an important concern. Ship position prediction for maritime situational awareness (MSA), as a critical aspect of maritime safety and security, requires a longer time interval than collision avoidance and maritime traffic monitoring. However, previous studies focused mainly on shorter time-interval predictions ranging from 30 min to 10 h. A longer time-interval ship position prediction is required not only for MSA, but also for efficient allocation of ships by shipping companies in accordance with global freight demand. This study used an end-to-end tracking method that inputs the previous position of a vessel to a trained deep learning model to predict its next position with an average 24-h interval. An AIS dataset with a long-time-interval distribution in a nine-year timespan for capesize bulk carriers worldwide was used. In the first experiment, a deep learning model of the Indian Ocean was examined. Subsequently, the model performance was compared for six different oceans and six primary maritime chokepoints to investigate the influence of each area. In the third experiment, a sample location within the Malacca Strait area was selected, and the number of ships was counted daily. The results indicate that the ship position can be predicted accurately with an average time interval of 24 h using deep learning systems with AIS data.


Assuntos
Aprendizado Profundo , Navios , Oceanos e Mares
10.
Environ Sci Technol ; 55(22): 15456-15465, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34724376

RESUMO

Sinking particulate organic matter (POM) is a primary component of the ocean's biological carbon pump that is responsible for carbon export from the surface to the deep sea. Lipids derived from plankton comprise a significant fraction of sinking POM. Our understanding of planktonic lipid biosynthesis and the subsequent degradation of lipids in sinking POM is based on the analysis of bulk samples that combine many millions of plankton cells or dozens of sinking particles, which averages out natural heterogeneity. We developed and applied a nanoflow high-performance liquid-chromatography electrospray-ionization high-resolution accurate-mass mass spectrometry lipidomic method to show that two types of sinking particles─marine snow and fecal pellets─collected in the western North Atlantic Ocean have distinct lipidomes, providing new insights into their sources and degradation that would not be apparent from bulk samples. We pressed the limit of this approach by examining individual diatom cells from a single culture, finding marked lipid heterogeneity, possibly indicative of fundamental mechanisms underlying cell division. These single-cell data confirm that even cultures of phytoplankton cells should be viewed as mixtures of physiologically distinct populations. Overall, this work reveals previously hidden lipidomic heterogeneity in natural POM and phytoplankton cells, which may provide critical new insights into microscale chemical and microbial processes that control the export of sinking POM.


Assuntos
Lipidômica , Fitoplâncton , Oceanos e Mares , Plâncton , Água do Mar
11.
Proc Natl Acad Sci U S A ; 118(47)2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34751160

RESUMO

The COVID-19 pandemic has led to an increased demand for single-use plastics that intensifies pressure on an already out-of-control global plastic waste problem. While it is suspected to be large, the magnitude and fate of this pandemic-associated mismanaged plastic waste are unknown. Here, we use our MITgcm ocean plastic model to quantify the impact of the pandemic on plastic discharge. We show that 8.4 ± 1.4 million tons of pandemic-associated plastic waste have been generated from 193 countries as of August 23, 2021, with 25.9 ± 3.8 thousand tons released into the global ocean representing 1.5 ± 0.2% of the global total riverine plastic discharge. The model projects that the spatial distribution of the discharge changes rapidly in the global ocean within 3 y, with a significant portion of plastic debris landing on the beach and seabed later and a circumpolar plastic accumulation zone will be formed in the Arctic. We find hospital waste represents the bulk of the global discharge (73%), and most of the global discharge is from Asia (72%), which calls for better management of medical waste in developing countries.


Assuntos
COVID-19/terapia , Oceanos e Mares , Plásticos , SARS-CoV-2 , Poluentes da Água , Países em Desenvolvimento , Saúde Global , Humanos
12.
Zootaxa ; 5051(1): 94-100, 2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34810905

RESUMO

The previously unknown females of Danielssenia spitsbergensis Gee Huys, 1994 and males of Mucrosenia kendalli Gee Huys, 1994 (Pseudotachidiidae, Danielsseniinae) are described based on specimens collected in the Kara and East Siberian Seas. Females of D. spitsbergensis exhibit the main diagnostic features of the genus Danielssenia Boeck, 1873 (antennule four-segmented; proximal segment of antennary exopod with one seta; structure of all the mouthparts; absence of an inner seta on exopod-1 of P2P4; P5 not fused medially and with distinct exopod and baseoendopod, the latter with five setae; genital field with small copulatory pore and short copulatory duct leading to seminal receptacle with paired anterior chambers). At the same time, these specimens also exhibit some distinctive features which are unique for the species but disagree with the generic diagnosis. These peculiarities validate the placing of D. spitsbergensis as species incertae sedis within Danielssenia and point out the necessity of examination of other 'Danielssenia-like forms before the true taxonomic position of this species can be elucidated. Both males and females of M. kendalli exhibit the autapomorphies of the genus, viz. P2 endopod-2 with a mucroniform process reaching almost to end of endopod-3 (this sexually dimorphic character is more pronounced in the males but also present in females); P2 endopod-2 without inner seta; posterior displacement of caudal ramus seta II; presence of tuft of long setules at inner distal corner of caudal ramus; P2 endopod shorter than exopod; P2P4 exopod-1 without inner seta. Furthermore, some particular features (anal somite and pseudoperculum morphology; female P1 endopod distinctly longer than exopod; P5 exopod with distinct suture on dorsal surface separating it from the baseoendopod; prominent mucroniform process on P2 endopod-2) of the Kara and East Siberian Sea specimens conform fully with the original description of M. kendalli but apparently differ from M. kliei (Smirnov, 1946), the single female of which was collected from the same region and depth. Therefore, the validity and definite status of the specimen described by Smirnov is still a matter of conjecture pending additional findings and, particularly, the discovery of the male.


Assuntos
Copépodes , Gastrópodes , Animais , Copulação , Feminino , Masculino , Oceanos e Mares
13.
Sensors (Basel) ; 21(20)2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34695933

RESUMO

Variations in the quantity of plankton impact the entire marine ecosystem. It is of great significance to accurately assess the dynamic evolution of the plankton for monitoring the marine environment and global climate change. In this paper, a novel method is introduced for deep-sea plankton community detection in marine ecosystem using an underwater robotic platform. The videos were sampled at a distance of 1.5 m from the ocean floor, with a focal length of 1.5-2.5 m. The optical flow field is used to detect plankton community. We showed that for each of the moving plankton that do not overlap in space in two consecutive video frames, the time gradient of the spatial position of the plankton are opposite to each other in two consecutive optical flow fields. Further, the lateral and vertical gradients have the same value and orientation in two consecutive optical flow fields. Accordingly, moving plankton can be accurately detected under the complex dynamic background in the deep-sea environment. Experimental comparison with manual ground-truth fully validated the efficacy of the proposed methodology, which outperforms six state-of-the-art approaches.


Assuntos
Plâncton , Procedimentos Cirúrgicos Robóticos , Mudança Climática , Ecossistema , Oceanos e Mares
14.
Sensors (Basel) ; 21(20)2021 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-34695965

RESUMO

Effective ocean management requires integrated and sustainable ocean observing systems enabling us to map and understand ecosystem properties and the effects of human activities. Autonomous subsurface and surface vehicles, here collectively referred to as "gliders", are part of such ocean observing systems providing high spatiotemporal resolution. In this paper, we present some of the results achieved through the project "Unmanned ocean vehicles, a flexible and cost-efficient offshore monitoring and data management approach-GLIDER". In this project, three autonomous surface and underwater vehicles were deployed along the Lofoten-Vesterålen (LoVe) shelf-slope-oceanic system, in Arctic Norway. The aim of this effort was to test whether gliders equipped with novel sensors could effectively perform ecosystem surveys by recording physical, biogeochemical, and biological data simultaneously. From March to September 2018, a period of high biological activity in the area, the gliders were able to record a set of environmental parameters, including temperature, salinity, and oxygen, map the spatiotemporal distribution of zooplankton, and record cetacean vocalizations and anthropogenic noise. A subset of these parameters was effectively employed in near-real-time data assimilative ocean circulation models, improving their local predictive skills. The results presented here demonstrate that autonomous gliders can be effective long-term, remote, noninvasive ecosystem monitoring and research platforms capable of operating in high-latitude marine ecosystems. Accordingly, these platforms can record high-quality baseline environmental data in areas where extractive activities are planned and provide much-needed information for operational and management purposes.


Assuntos
Ecossistema , Salinidade , Humanos , Oceanos e Mares
15.
BMC Ecol Evol ; 21(1): 192, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34674635

RESUMO

BACKGROUND: The evolutionary processes that shape patterns of species richness in marine ecosystems are complex and may differ between organismal groups. There has been considerable interest in understanding the evolutionary processes that led to marine species richness being concentrated in specific geographical locations. In this study we focus on the evolutionary history of a group of small-to-medium sized sharks known as carpet sharks. While a few carpet shark species are widespread, the majority of carpet shark species richness is contained within a biodiversity hotspot at the boundary of the Indian and Pacific oceans. We address the significance of this biodiversity hotspot in carpet shark evolution and speciation by leveraging a rich fossil record and molecular phylogenetics to examine the prehistoric distribution of carpet sharks. RESULTS: We find that carpet sharks species richness was greatest in shallow seas connected to the Atlantic Ocean during the Late Cretaceous, but that there was a subsequent loss of biodiversity in Atlantic waters. Fossil evidence from sites in close geographic proximity to the current center of carpet shark diversity are generally restricted to younger geologic strata. CONCLUSIONS: From this data we conclude that (1) center of carpet shark biodiversity has shifted during the last 100 million years, (2) carpet sharks have repeatedly dispersed to nascent habitat (including to their current center of diversity), and (3) the current center of carpet shark biodiversity conserves lineages that have been extirpated from this prehistoric range and is a source of new carpet shark species. Our findings provide insights into the roles of marine biodiversity hotspots for higher-tropic level predators and the methods applied here can be used for additional studies of shark evolution.


Assuntos
Tubarões , Animais , Biodiversidade , Ecossistema , Oceanos e Mares , Oceano Pacífico , Tubarões/genética
16.
Environ Monit Assess ; 193(11): 720, 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34643825

RESUMO

Long-term variation of nitrate in the East Sea was monitored in order to investigate impact of Three Gorges Dam (TGD) in the Changjiang River's upstream, China and Nakdong River's estuary dam, Korea. Tracing source of nitrate was another objective in this study. For this study, nutrient data were collected for 20 years from 1999 to 2018 in the East Sea, and divided into 4 sections, and evaluated whether a significant difference exists among the averages of nitrate concentrations. The concentrations of nitrate were affected by the major rivers (the Nakdong and the Taehwa Rivers) and Tsushima Warm Current (TWC) which diverged from the Kuroshio Current passing through East China Sea (ECS). Our results also indicated that long-term nitrate concentrations decreased and its reasons. First, the construction of TGD in the upstream of the Changjiang River may have resulted in the decrease of the nitrate supply in the river and ECS which is carried by TWC, toward the East Sea. Second, decrease in the nitrate flux of the Nakdong River's estuary due to the construction of the estuary dam and sewer treatment plant could also be a factor for the nitrate decrease in the East Sea. Therefore, anthropogenic activities from the Nakdong River and Changjiang River had a long-term effect on the East Sea's nitrate concentrations. The amount of nitrate runoff reduced by the anthropogenic activities influenced the nitrate levels over a long period by the flow of currents in the East Sea.


Assuntos
Monitoramento Ambiental , Nitratos , China , Estuários , Nitratos/análise , Oceanos e Mares , República da Coreia , Rios
17.
Aerosp Med Hum Perform ; 92(9): 720-727, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34645552

RESUMO

BACKGROUND: The objectives were to assess the prevalence, severity, and medication taken, and to look for predictive factors in order to better identify characteristics of passengers at risk of motion sickness during transport from Hobart in Tasmania to the French polar stations in Antarctica. METHODS: There were 239 passengers who were surveyed over 4 yr with 4 round trips per year using the Motion Sickness Susceptibility Questionnaire (MSSQ), Simulator Sickness Questionnaire (SSQ), state-trait anxiety test (STAI-Trait and STAI-State), and general parameters (age, gender, number of trips, jet-lag, direction of the trip), medication, calculation of the distance of each passengers cabin to the center of gravity (CoG). RESULTS: While the passengers had a low intrinsic sensitivity to motion sickness (MSSQ), 94 reported at least one SSQ symptom of motion sickness, and 38 vomited. Five associated factors were discovered: greater initial sensitivity (MSSQ), anticipation of being ill, younger age, higher level of anxiety at midtrip, and greater distance from the CoG. Of the passengers, there were 54 who took anti-motion sickness medication at different times of the trip, however, these passengers experienced more nausea. This could be due to self-selection since they were more sensitive to motion sickness. CONCLUSION: We identified three predictive factors of motion sickness (greater intrinsic susceptibility, younger age, and greater cabin distance from the CoG). For preventive purposes, two associated factors of MS (anticipation of being ill, MSSQ score) were determined to classify three groups of risk of MS to improve passenger care during the trip. Besnard S, Bois J, Hitier M, Vogt J, Laforet P, Golding JF. Motion sickness lessons from the Southern Ocean. Aerosp Med Hum Perform. 2021; 92(9):720727.


Assuntos
Enjoo devido ao Movimento , Humanos , Enjoo devido ao Movimento/epidemiologia , Náusea , Oceanos e Mares , Inquéritos e Questionários , Vômito
18.
Microbiome ; 9(1): 207, 2021 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-34654476

RESUMO

BACKGROUND: Dimethyl sulfide (DMS) is the dominant volatile organic sulfur in global oceans. The predominant source of oceanic DMS is the cleavage of dimethylsulfoniopropionate (DMSP), which can be produced by marine bacteria and phytoplankton. Polar oceans, which represent about one fifth of Earth's surface, contribute significantly to the global oceanic DMS sea-air flux. However, a global overview of DMS and DMSP cycling in polar oceans is still lacking and the key genes and the microbial assemblages involved in DMSP/DMS transformation remain to be fully unveiled. RESULTS: Here, we systematically investigated the biogeographic traits of 16 key microbial enzymes involved in DMS/DMSP cycling in 60 metagenomic samples from polar waters, together with 174 metagenome and 151 metatranscriptomes from non-polar Tara Ocean dataset. Our analyses suggest that intense DMS/DMSP cycling occurs in the polar oceans. DMSP demethylase (DmdA), DMSP lyases (DddD, DddP, and DddK), and trimethylamine monooxygenase (Tmm, which oxidizes DMS to dimethylsulfoxide) were the most prevalent bacterial genes involved in global DMS/DMSP cycling. Alphaproteobacteria (Pelagibacterales) and Gammaproteobacteria appear to play prominent roles in DMS/DMSP cycling in polar oceans. The phenomenon that multiple DMS/DMSP cycling genes co-occurred in the same bacterial genome was also observed in metagenome assembled genomes (MAGs) from polar oceans. The microbial assemblages from the polar oceans were significantly correlated with water depth rather than geographic distance, suggesting the differences of habitats between surface and deep waters rather than dispersal limitation are the key factors shaping microbial assemblages involved in DMS/DMSP cycling in polar oceans. CONCLUSIONS: Overall, this study provides a global overview of the biogeographic traits of known bacterial genes involved in DMS/DMSP cycling from the Arctic and Antarctic oceans, laying a solid foundation for further studies of DMS/DMSP cycling in polar ocean microbiome at the enzymatic, metabolic, and processual levels. Video Abstract.


Assuntos
Água do Mar , Oceanos e Mares , Filogenia , Sulfetos , Compostos de Sulfônio
19.
Prog Chem Org Nat Prod ; 116: 1-36, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34698944

RESUMO

The term "marine biodiscovery" has been recently been adopted to describe the area of marine natural products dedicated to the search of new drugs. Several maritime countries such as Australia, New Zealand, South Korea, and Japan as well as some European countries have invested significantly in this area of research over the last 50 years. In the late 2000s, research in this field has received significant interest and support in Ireland for exploring new marine bioresources from the nutrient-rich waters of the Northeastern Atlantic Ocean. Despite undeniable success exemplified by the marketing of new drugs, especially in oncology, the integration of new technical but also environmental aspects should be considered. Indeed, global change, particularly in our oceans, such as climate change, biodiversity loss, and the emergence of microbial pathogens, not only affects the environment but ultimately contributes to social inequalities. In this contribution, new avenues and best practices are proposed, such as the development of biorepositories and shared data for the future of marine biodiscovery research. The extension of this type of scientific work will allow humanity to finally make the optimum use of marine bioresources.


Assuntos
Biodiversidade , Produtos Biológicos , Oceano Atlântico , Austrália , Oceanos e Mares
20.
Environ Sci Technol ; 55(20): 14269-14280, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34618428

RESUMO

Globally, the consumption of coastal fish is the predominant source of human exposure to methylmercury, a potent neurotoxicant that poses health risks to humans. However, the relative importance of riverine inputs and atmospheric deposition of mercury into coastal oceans remains uncertain owing to a lack of riverine mercury observations. Here, we present comprehensive seasonal observations of riverine mercury and methylmercury loads, including dissolved and particulate phases, to East Asia's coastal oceans, which supply nearly half of the world's seafood products. We found that East Asia's rivers annually exported 95 ± 29 megagrams of mercury to adjacent seas, 3-fold greater than the corresponding atmospheric deposition. Three rivers alone accounted for 71% of East Asia's riverine mercury exports, namely: Yangtze, Yellow, and Pearl rivers. We further conducted a metadata analysis to discuss the mercury burden on seawater and found that riverine export, combined with atmospheric deposition and terrestrial nutrients, quantitatively elevated the levels of total, methylated, and dissolved gaseous mercury in seawater by an order of magnitude. Our observations support that massive amounts of riverine mercury are exported to coastal oceans on a continental scale, intensifying their spread from coastal seawater to the atmosphere, marine sediments, and open oceans. We suggest that the impact of mercury transport along the land-ocean aquatic continuum should be considered in human exposure risk assessments.


Assuntos
Mercúrio , Poluentes Químicos da Água , Animais , China , Monitoramento Ambiental , Humanos , Mercúrio/análise , Oceanos e Mares , Rios , Água do Mar , Poluentes Químicos da Água/análise
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