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1.
Mar Pollut Bull ; 163: 111966, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33465635

RESUMO

To evaluate the heavy metal contamination, ecological risk and possible sources at Saudi Yanbu coastline, 30 sediment samples were collected for Fe, Pb, Ni, As, Zn, Cu, Cr, Co, Al, Sb, Cd, and TOC analyses using ICP-MS. The potential ecological risk index (PERI), enrichment factor (EF), contamination factor (CF), potential contamination index (Cp), geoaccumulation index (Igeo), soil pollution index (SPI) were calculated and interpreted, and multivariate analyses were applied. The results indicated the following order for metal averages: Al (8573 µg/g) > Fe (5895 µg/g) > Mn (192 µg/g) > Zn (80.4 µg/g) > Cu (35.87 µg/g) > Cr (27.11 µg/g) > Ni (23.5 µg/g) > Co (8.29 µg/g) > Pb (7.72 µg/g) > As (6.83 µg/g) > Sb (0.50 µg/g) > Hg (0.33 µg/g) > Cd (0.30 µg/g). Average levels of As, Ni, Zn, Co, Cd, and Pb values were greater than those reported from many coastal sediments from the Red Sea, Gulf of Aqaba, Arabian Gulf and Mediterranean Sea, as well as the sediment quality guidelines. The results of potential ecological risk revealed very high risk for Cd, high risk for Hg, considerable risk for Cu, Sb, and As, moderate risk for Pb and Ni, and no to low risk for Zn and Cr. The moderately severe enriched HMs (Cd, Zn, Cu, Hg) and the moderate enriched ones (Pb, Co, As) were originated mostly from anthropogenic sources related to industrial, agricultural, urbanization and fishing activities. The no and minor enriched HMs (Fe, Al, Ni, Cr, Sb) were mostly related to lithogenic factors related to rock weathering and atmospheric inputs.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Oceano Índico , Mar Mediterrâneo , Metais Pesados/análise , Medição de Risco , Arábia Saudita , Poluentes Químicos da Água/análise
2.
Mar Pollut Bull ; 163: 111909, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33486406

RESUMO

In this investigation, δ13C and δ15N isotope ratios and heavy metal levels were assessed in macroalgae, sediment samples, and benthic species from northern parts of the Persian Gulf and the Gulf of Oman. The highest δ15N values in algal samples (11±0.42), indicative of anthropogenic organic N inputs, were detected in the Sadaf region, whereas the lowest values (3.17 ±â€¯0.12), indicative of anthropogenic inorganic inputs, were detected in the Parvaz region. In addition to sediment quality guidelines (SQGs), contamination factors (CF), enrichment factors (EF), contamination degree (CD), pollution load index (PLI), geo accumulation index (Igeo), and potential ecological risk index (RI) were employed to assess the anthropogenic influence on sediment quality and to describe the sensitivity of the biota to toxic heavy metals. The obtained results demonstrate that the analyzed elements (Mn, Cr, Ni, Pb, Zn, Cu, Co, and V) had no ecological risk in the sampling area.


Assuntos
Metais Pesados , Alga Marinha , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Oceano Índico , Isótopos , Metais Pesados/análise , Omã , Medição de Risco , Poluentes Químicos da Água/análise
3.
Mar Pollut Bull ; 163: 111975, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33493850

RESUMO

To evaluate the heavy metal contamination and groundwater quality in southern Saudi Arabia, 105 groundwater samples were analyzed for EC, pH, TDS, major ions (NO3-, Cl-, HCO3-, SO42-, F-, Ca2+, Mg2+, Na+, and K+), and heavy metals (Fe, Li, As, B, Al, Cr, Cu, Mo, Ni, Se, Sr, V, Zn, and Mn). Groundwater quality index (GWQI), degree of contamination (Cd), heavy metal pollution index (HPI), ecological risks of heavy metals (ERI), salinity hazard (EC), sodium adsorption ratio (SAR), sodium percentage (Na%), and Kelly's ratio (KR) were calculated and compared, and multivariate statistical techniques were applied. The results revealed that the major cations and anions followed the orders of Na+ > Ca2+ > Mg2+ > K+ and Cl- > SO42- > HCO3- > NO3- > F-, respectively. The maximum values of As, Mn, Cr, Ni, Se, and Zn were above the permissible limits for drinking water purposes. Pollution indices indicated that 20 to 52% of the groundwater samples were suitable for agricultural and domestic purposes. The unsuitable samples were distributed mostly in the western part along the Red Sea coast. Multivariate statistical analyses revealed that the dissolution of halite and gypsum (in sabkha deposits), carbonates, and the agricultural activities were the possible sources of the major cations and anions, and heavy metals in the study area.


Assuntos
Água Subterrânea , Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Oceano Índico , Metais Pesados/análise , Arábia Saudita , Poluentes Químicos da Água/análise , Qualidade da Água
4.
Mar Environ Res ; 163: 105215, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33360640

RESUMO

Coral reefs are threatened worldwide by global climate change, manifested in anthropogenic ocean warming and acidification. Despite the importance of coral sexual reproduction for the continuity of coral reefs, our understanding of the extent of the impact of climate change on coral sexual reproduction, particularly on coral reproductive phenology and early life stages, is limited. Here, we experimentally examined the effects of predicted end-of-the-century seawater conditions on the sexual reproduction and photosynthetic capacity of a Red-Sea zooxanthellate octocoral, Rhytisma fulvum. Sexually mature colonies were exposed to ambient temperature and pH conditions and to Representative Concentration Pathway (RCP) conditions (4.5 and 8.5), five weeks prior to their expected surface-brooding event. The reproductive phenology of the colonies under the simulated seawater conditions was compared to that on the natural reef. In addition, subsequent planulae development and their metamorphosis into primary polyps under the same RCP conditions as their parent colonies were monitored in a running seawater system. The results reveal that both RCP conditions led to a change in the timing of onset of the surface-brooding event and its synchronicity. In contrast, the surface-brooding event under ambient conditions co-occurred with that of the in-situ reef colonies and maintained its synchrony. Similarly, planula survival and polyp metamorphosis rate were significantly reduced under both RCP conditions compared to propagules reared under ambient conditions. In addition, the photosynthetic capacity of the parent colonies under both RCPs showed a reduction relative to that under the ambient conditions in the experiment, suggesting a reduction in carbon fixation during the late stages of gametogenesis. While our findings indicate that octocoral reproductive phenology is affected by environmental changes, further work is required in order to elucidate the long-term implications for the R. fulvum population in the northern Red Sea.


Assuntos
Antozoários , Animais , Mudança Climática , Recifes de Corais , Oceano Índico , Reprodução , Água do Mar , Temperatura
5.
Sci Total Environ ; 751: 141807, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33181997

RESUMO

The contamination of tiger sharks (Galeocerdo cuvier) and bull sharks (Carcharhinus leucas) by legacy persistent organic pollutants (POPs) and emerging organic contaminants was investigated in specimens from Reunion Island (Southwest Indian Ocean) in 2018 and 2019. Contamination levels were determined in the muscle of adult individuals of both sexes in relation to biological and trophic parameters. Maternal transfer was additionally investigated in one set of embryos in each species. Polychlorinated biphenyl (PCB), organochlorinated pesticide (OCP) and perfluoroalkylated substance (PFAS) concentrations were 2597 ± 2969, 785 ± 966 and 267 ± 194 pg g-1 ww, respectively, in bull sharks, and 339 ± 270, 1025 ± 946 and 144 ± 53 pg g-1 ww in tiger sharks. The results highlighted higher PCB contamination, and by the heavier congeners, in adult bull sharks versus tiger sharks. The significant differences found in PCB profiles and concentrations suggest that the two species are exposed to different contamination sources. As bull sharks rely on a more coastal habitat for feeding, their higher contamination by PCBs suggests the occurrence of local PCB sources. DDT concentrations were similar in both species, suggesting a more homogeneous contamination on the scale of the Southwest Indian Ocean. Female bull sharks showed lower OCP and PCB concentrations than males, while this trend was not observed in tiger sharks. The ratio of chlorinated contaminants in muscle between the mother and her embryos was related to molecule hydrophobicity in bull shark but not in tiger shark, suggesting that shark mode of gestation, known to be different in the two species, is a key driver of organic contaminant maternal transfer. Finally, the results show that organic contaminant levels in the studied species were lower than those of other shark species in the Southern Hemisphere, related to the limited urbanization and industrialization of Reunion Island.


Assuntos
Bifenilos Policlorados , Tubarões , Animais , Feminino , Humanos , Oceano Índico , Masculino , Bifenilos Policlorados/análise , Reunião , Alimentos Marinhos
6.
Chemosphere ; 262: 128039, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182145

RESUMO

Wastewater discharge is considered to be a significant point source of microplastic (MPs) release into the marine environment. This study is the first attempt to quantify MPs released from the wastewater outfall from Bandar Abbas City into the Persian Gulf. Two wastewater discharge stations at Gursuzan and Suru were sampled. MPs were isolated by an oxidative procedure and subsequent density separation using ZnCl2 solution. The average MP concentration in wastewater and sludge were 70.66 (±14.12, SD) MP.35 L-1 and 6070 (±807.25) MPs.kg-1, respectively at Confidence Level (CL) (95.0%). The most commonly recovered polymers were polyethylene (PE) and polypropylene (PP) in all size classes. Our findings provides a baseline of MP concentration in wastewater streams and slurry that is discharged from the Bandar Abbas wastewater treatment facility into the Persian Gulf. This highlights the need to undertake more studies at water treatment plants in the region for a realistic assessment of MP discharge into the Persian Gulf.


Assuntos
Monitoramento Ambiental/métodos , Microplásticos/análise , Esgotos/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Oceano Índico , Irã (Geográfico) , Polietileno/análise , Polipropilenos/análise
7.
Ambio ; 50(1): 60-73, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31997147

RESUMO

Farming of eucheumatoid seaweeds is a widespread, promising activity and an important livelihood option in many tropical coastal areas as for example in East Africa, Western Indian Ocean (WIO). Compared to other types of aquaculture, seaweed farming has generally low impact on the environment. Nonetheless, there are potential direct or indirect negative effects of seaweed farming, such as introduction of alien species and changes in local environmental conditions. Although farming has been practiced in this region during several decades, the knowledge concerning the actual environmental impacts from faming non-native eucheumatoid haplotypes and consequently how to manage farming activities to mitigate those is highly limited. In this review, we provide a summary of the current scientific knowledge of potential direct and indirect negative environmental effects linked to eucheumatoid seaweed farming such as alterations of benthic macrophyte habitats and loss of native biodiversity. Furthermore, we highlight knowledge gaps that are of importance to address in the near future, e.g., large-scale ecosystem effects and farms as potential vectors of pathogens. We also provide a number of feasible management recommendations to be implemented for a continued development of environmentally sustainable seaweed farming practices in the WIO region, which includes spatial planning of farms to avoid sensitive areas and farming of native haplotypes of eucheumatoids instead of introduced specimens.


Assuntos
Alga Marinha , África Oriental , Agricultura , Ecossistema , Oceano Índico
8.
Water Res ; 188: 116509, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33069950

RESUMO

Effective pollution control and remediation strategies are the key to providing a major progress in conservation of coastal and marine biodiversity. For the development of such strategies, quantitative assessment of potentially toxic metals (PTMs) and the accurate identification of the pollutant sources are essential. In this study, we seek to find out spatial PTMs distribution in the coastal sediments of the Persian Gulf (Iran), to assess the potential eco-environmental risks and to identify the metal pollution sources. Total and fraction analysis indicated considerable metal (Zn, Cu, Mn, Fe, Al, Hg, Pb, Cd, As, Cr, Co, Ni and V) pollution levels, albeit in most cases PTMs were predominantly associated with the oxidizable and residual fractions. The obtained PTMs concentrations were in the range of 22.8 - 156.3, 16.6 - 161.9; 2.7 - 88; 10.4 - 107.3; 1.1 - 35.8; 0.8 - 27.9; 0.1 - 1.3; 1.1 - 21.3; 0.04 - 1.9 mg.kg-1 for V, Ni, Cu, Zn, Cr, Co, Hg, Pb, and Cd, respectively. The combined PTM-PCA-PMF modeling approach identified four main metal sources (anthropogenic, vehicle-related, agricultural and lithogenic) in the study area. Several recognizable 'hot-spots' with extremely high metal concentrations were observed in the spatial metal pollution patterns. Some of those locations were predominantly affected by the nearby industrial activities, while others have demonstrated contributions from several sources - not only anthropogenic, but also agricultural and vehicle-related. The same spots of elevated pollution were found to demonstrate higher potential eco-environmental risk. Various indexes indicated more or less similar trends: the eco-environmental risk was gradually increasing towards the northwestern part of the study area with several peaks in the central and eastern parts directly affected by the nearby industrial activities.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Oceano Índico , Irã (Geográfico) , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise , Pesos e Medidas
9.
Mar Pollut Bull ; 162: 111901, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33310377

RESUMO

This literature review was conducted to collect present data on microplastics pollution in Iran's ecosystems. Most of the studies performed in aquatic environment were conducted in Persian Gulf & Oman Sea (70%). The Persian Gulf, along with the beaches of Bushehr and Hormozgan Provinces, are the most studied areas. Moreover, most of the studies were conducted in aquatic environments and only four studies were conducted in terrestrial environment (4/42). One study has assessed microplastics in commercial salt and another study has reported the microplastics presence in Iranian bottled mineral water brands. The investigation of microplastics associated with biota was highlighted, customarily for fish species. Microplastics were also present in urban wastewater samples in Sari and Bandar Abbas cities. Three studies were performed in freshwater ecosystems until now (Haraz River, Anzali wetland, and Taleqan dam). The need for further studies in this field still exists, especially in terrestrial and freshwater compartments.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Cidades , Ecossistema , Monitoramento Ambiental , Oceano Índico , Irã (Geográfico) , Omã , Plásticos , Poluentes Químicos da Água/análise
10.
Mar Pollut Bull ; 162: 111921, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33341595

RESUMO

Four oil spill events over the Indian Ocean including Chennai, Sharjah, Al Khiran and Mubarak Village are analyzed using Sentinel-1 satellite data. General National Oceanic and Atmospheric Administration (NOAA) Operational Modeling Environment (GNOME) model is utilized for oil spills trajectory production, whereas oil spills weathering processes are modeled using Automated Data Inquiry for Oil Spill (ADIOS). Synthetic Aperture Radar (SAR) based oil spill detection technique provided reliable results at the wind speed between 3 to 9 m/s for all events. Maximum oil spill movement (33 km) from the source point is observed in the Al Khiran, whereas evaporation rate of crude (degraded) oil is observed as high (low). The Near Real Time (NRT) detection of oil spill using SAR imagery needs high computational power, however, provides better results. This study concludes that SAR based oil spill detection is a cost-effective technique and can be utilized for mapping of oil spills.


Assuntos
Poluição por Petróleo , Petróleo , Poluentes Químicos da Água , Monitoramento Ambiental , Índia , Oceano Índico , Petróleo/análise , Poluição por Petróleo/análise , Radar , Poluentes Químicos da Água/análise
11.
Toxicon ; 191: 69-82, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33359388

RESUMO

The Mediterranean region is, by far, a prime travel destination, having hosted more than 330 million tourists in 2016, mostly for seaside holidays. A greatly increased influx of thermophilic Red Sea species, introduced through the Suez Canal in a process referred to as Lessepsian invasion (in honor of Ferdinand de Lesseps who instigated the building of the Suez Canal), have raised awareness among scientists, medical personnel, and the public, of health risks caused by some venomous and poisonous marine species. The main species of concern are the poisonous Lagocephalus sceleratus, and the venomous Plotosus lineatus, Siganus luridus, Siganus rivulatus, Pterois miles, Synancea verrucosa, Rhopilema nomadica, Macrorhynchia philippina and Diadema setosum. Recognizing that the main factors that drive the introduction and dispersal of Red Sea biota in the Mediterranean, i.e., Suez Canal enlargements and warming seawater, are set to increase, and international tourist arrivals are forecasted to increase as well, to 500 million in 2030, an increase in intoxications and envenomations by alien marine species is to be expected and prepared for.


Assuntos
Organismos Aquáticos , Espécies Introduzidas , Toxinas Biológicas , Animais , Peixes-Gato , Ecossistema , Humanos , Oceano Índico , Mar Mediterrâneo , Perciformes , Tetraodontiformes
12.
Chemosphere ; 267: 129316, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33352370

RESUMO

Persistent halogenated compounds (PHC) are of concern for human and environmental health. Persistent Organic Pollutants (POPs) are regulated by international treaties, but alternative compounds such as novel brominated flame retardants (NBFRs) and Dechlorane Plus (DP) are not-yet they are increasingly used. There are no data on PHCs in coral reef biota from tropical islands in the western Indian Ocean (WIO). For this assessment, three hard coral genera, two soft coral genera, and ember parrotfish (Scarus rubroviolaceus) were collected from the remote Rodrigues, Agalega, and St. Brandon's Atoll (Republic of Mauritius) in the Mascarene Basin of the WIO. Five compounds - Pentabromotoluene (PBT), γ-HCH, p,p'-DDE, HCB, and BDE-47- were quantifiable in all samples. Hard coral consistently contained the lowest concentrations of PHCs, except for NBFRs. The presence of BDE-47 suggests long-range aerial transport. We quantified DP, currently a candidate POP, in coral reef biota. PBT was measured in all samples also suggests long-range transport. Because the hard coral, soft coral, and fish had differing concentrations and patterns of PHCs, future surveys should stratify sampling accordingly. Agalega and St. Brandon's Atoll can be considered as locations to monitor changes in background concentrations of pollutants due to their remoteness.


Assuntos
Antozoários , Retardadores de Chama , Animais , Recifes de Corais , Monitoramento Ambiental , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Humanos , Oceano Índico , Ilhas
13.
Sci Total Environ ; 751: 141453, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32882547

RESUMO

Trace metals such as Cu, Hg, and Zn have been widely investigated in marine ecotoxicological studies considering their bioaccumulation, transfer along trophic webs, and the risks they pose to ecosystems and human health. Comparatively, Li has received little attention, although this element is increasingly used in the high-tech, ceramics/glass, and medication industries. Here, we report Li concentrations in more than 400 samples, including whole organisms and different organs of bivalves, cephalopods, crustaceans, and fish. We investigated species from three contrasting biogeographic areas, i.e. temperate (Bay of Biscay, northeast Atlantic Ocean), tropical (New Caledonia, Pacific Ocean), and subpolar climates (Kerguelen Islands, southern Indian Ocean), among diverse trophic groups (filter-feeders to meso-predators) and habitats (benthic, demersal, and pelagic). Although Li is homogeneously distributed in the ocean (at 0.18 µg/mL), Li concentrations in soft tissues vary greatly, from 0.01 to 1.20 µg/g dry weight. Multiple correspondence analyses reveal two clusters of high and low Li concentrations. Li distributions in marine organisms appear to be mostly geographically independent, though our results highlight a temperature dependency in fish muscles. Li is consistently bio-reduced through the trophic webs, with filter-feeders showing the highest concentrations and predatory fish the lowest. Strong variations are observed among organs, consistent with the biochemical similarity between Na and Li during transport in the brain and in osmoregulatory organs. Fish gills and kidneys show relatively high Li concentrations (0.26 and 0.15 µg/g, respectively) and fish brains show a large range of Li contents (up to 0.34 µg/g), whereas fish liver and muscles are Li depleted (0.07 ± 0.03 and 0.06 ± 0.08 µg/g, respectively). Altogether, these results provide the first exhaustive baseline for future Li ecotoxicology studies in marine coastal environments.


Assuntos
Organismos Aquáticos , Poluentes Químicos da Água , Animais , Oceano Atlântico , Ecossistema , Monitoramento Ambiental , Peixes , Cadeia Alimentar , Humanos , Oceano Índico , Lítio , Nova Caledônia , Oceano Pacífico , Inquéritos e Questionários , Poluentes Químicos da Água/análise
14.
Sci Total Environ ; 751: 141628, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32896805

RESUMO

In coral reefs, dissolved organic matter (DOM) cycling is a critical process for sustaining ecosystem functioning. However, global and local stressors have caused persistent shifts from coral- to algae-dominated benthic communities. The influence of such phase shifts on DOM nature and its utilization by heterotrophic bacterioplankton remains poorly studied. Every second month for one year, we retrieved seawater samples enriched in DOM produced by coral- and algae-dominated benthic communities in a central Red Sea reef during a full annual cycle. Seawater incubations were conducted in the laboratory under in situ temperature and light conditions by inoculating enriched DOM samples with bacterial assemblages collected in the surrounding waters. Dissolved organic carbon (DOC) concentrations were higher in the warmer months (May-September) in both communities, resulting in higher specific growth rates and bacterial growth efficiencies (BGE). However, these high summer values were significantly enhanced in algal-DOM relative to coral-DOM, suggesting the potential for bacterioplankton biomass increase in reefs with algae replacing healthy coral cover under warmer conditions. The potential exacerbation of heterotrophic bacterial activity in the ongoing widespread regime shift from coral- to algae-dominated communities may have detrimental consequences for the overall health of tropical coral reefs.


Assuntos
Antozoários , Animais , Recifes de Corais , Ecossistema , Processos Heterotróficos , Oceano Índico
15.
Zootaxa ; 4861(3): zootaxa.4861.3.2, 2020 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-33311212

RESUMO

The present study is based on material collected in the intertidal and shallow subtidal areas of two Islands in the Persian Gulf, Abu-Musa and Larak. The new species, Synalpheus pentaspinosus n. sp., is closely related to S. quinquedens Tattersall, 1921. These two species share a very characteristic, sixth pleonite armed posteriorly with five stout sharp teeth, a feature unique within the genus. The color of ovaries or freshly laid eggs, red-orange in S. pentaspinosus n. sp. vs. green in S. quinquedens, is the most obvious character, by which the new species may be distinguished from S. quinquedens in the field. In addition, the two species can be separated by two characters on the dactylus of the minor cheliped. In the new species, the dactylus is furnished with two prominent rows of setae, one dorsally and one mesially, and has a small concavity on the cutting edge, contrasting to only one mesial row of setae and no obvious concavity in S. quinquedens.


Assuntos
Decápodes , Distribuição Animal , Estruturas Animais , Animais , Oceano Índico
16.
Zootaxa ; 4885(2): zootaxa.4885.2.2, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33311275

RESUMO

Oxynoemacheilus marunensis, new species, is described from the Marun, a tributary of the Jarrahi River, which flows just east of the Tigris River to the Persian Gulf. It belongs to a group of species (O. argyrogramma, O. euphraticus, O. hanae, O. karunensis, and O. kurdistanicus) having two bold, black, round, or comma-shaped black spots on the caudal-fin base. It is most similar to a newly described species from the Persian Gulf basin, O. karunensis, but distinguished from O. karunensis by having a longer distance between pelvic and anal-fin origins [22.3-23.8 vs. 19.5-22.3 (% SL)] and a K2P distance of 6% based on COI barcode region sequences.


Assuntos
Cipriniformes , Animais , Cor , Oceano Índico , Rios
17.
Mar Pollut Bull ; 160: 111544, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181916

RESUMO

Seagrass longevity up to 47 years in well-restored, well-sited seagrass restorations are demonstrated from 253 trials at 83 regional sites in tropical and subtropical portions of three oceans (Atlantic, Pacific, Indian Oceans). These trials include over 3.04 million planted units into 306.3 ha. Approximately 12% of the total global tropical restored seagrass by Van Katwijk, Thorhaug et al. (2016) calculations from 1786 trials are included. Almost all projects herein reviewed persisted since date of planting except several cases with harsh anthropogenic impact or forceful natural events in first post-planting months. The oldest tropical/subtropical restoration continually observed is 47 yrs, many are 35 yrs. An array of observed and/or measured restored services accompanied these. This review may provide informational background for government resource managers, legislators, scientists, and citizens concerning tropical/subtropical seagrass longevity. This data from these trials may substantiate future seagrass restoration investments. Public outreach, national & regional government training,and outreach occurred, needing continuation.


Assuntos
Ecossistema , Longevidade , Oceano Índico
18.
Mar Pollut Bull ; 160: 111643, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181926

RESUMO

The present study was carried out at 22 stations located on the fringing reefs of the island of Mayotte inside the perimeter of the Marine Natural Park of Mayotte (PNMM). The average assessment of the number of samples of marine litter (ML) collected at these stations was 3.9 ± 1.3 ML per 500 m2 in winter and 3.8 ± 1.1 ML per 500 m2 in summer. Plastic ML was dominant, representing approximately 92% of the litter collected at the stations for the two seasons. The majority was plastic ML from fishing gear (lines, nets etc.). Station 18 presented remarkable average densities of 39 ± 4.2 ML per 500 m2 for the two seasons and differed from the other stations in that the ML came solely from the catchment areas, with a majority of aluminium ML (56%). Approximately half the coral colonies coming into contact with ML presented an impact dominated by the category of "Broken or abraded colonies", with 25% of the colonies being impacted. The colonies most severely impacted by ML were branch or table corals, with the greatest majority for the present study being of the genus Acropora.


Assuntos
Antozoários , Animais , Comores , Recifes de Corais , França , Oceano Índico , Ilhas
19.
Zootaxa ; 4834(4): zootaxa.4834.4.3, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-33056104

RESUMO

The highly diverse goatfish genus Upeneus (Mullidae) requires enhanced attention regarding the possible occurrence of undescribed species in insufficiently explored regions. This study focuses on the South-Western Indian Ocean region (SWIO), and on the so-called japonicus-group, a taxonomic species group of Upeneus. Based on in-situ observations and collections in Sodwana Bay, KwaZulu-Natal, South Africa, the Floros goatfish, U. floros n. sp., is described. Detailed comparative studies of colour patterns and morphological characters of all other 13 japonicus-group species were undertaken as well as COI barcoding. The new species occurs in the coastal area between Angoche, N Mozambique and KwaZulu-Natal and partly overlaps in distribution with two similar species, U. guttatus, widely distributed in the Indo-W Pacific, and U. saiab, assumed to be endemic in a small area off Angoche. Two additional japonicus-group species occurring in the SWIO, U. seychellensis from the Seychelles Bank and U. pori from the Mediterranean Sea (as Lessepsian migrant), Northern Red Sea and Madagascar, were also compared. Because specimens as well as in-situ photographs of U. floros have been erroneously identified as either U. guttatus or U. pori during previous studies, updated taxonomic accounts and diagnoses are provided for these species taking size-related and population differences into account. For U. pori, of which a single preserved specimen from SW Madagascar was known so far, a new record from NE Madagascar is reported based on three specimens and a fresh-colour photo. Upeneus floros can be distinguished from U. guttatus and U. pori by a combination of three characters: head length, first dorsal-fin height and number of gill rakers. Upeneus guttatus can be distinguished from the other two species by disproportionally higher anterior dorsal-fin spines vs. a proportional decrease of dorsal-fin spines in height, barbels mostly yellow vs. white or creamy-white, and slightly fewer pectoral-fin rays. COI barcoding detected a clear distinction between U. guttatus and U. floros and U. pori, respectively, but no significant divergence between the two latter species. COI barcoding also failed to differentiate several other Upeneus species which are clearly distinguished morphologically. Possible interrelationships between species distribution patterns and physical oceanography are discussed. An identification key for the 22 WIO Upeneus species is provided.


Assuntos
Peixes , Animais , Oceano Índico , Moçambique , África do Sul
20.
Zootaxa ; 4834(1): zootaxa.4834.1.1, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-33056129

RESUMO

Three digeneans belonging to the Opecoelidae are reported and described from triggerfishes (Tetraodontiformes: Balistidae) collected in the northern Red Sea off Egypt. Both Macvicaria longicirrata (Manter, 1963) Aken-Ova, Cribb Bray, 2008 and Neopycnadena tendu (Bray Justine, 2007) n. comb. were recovered from the intestine of the titan triggerfish, Balistoides viridescens (Bloch Schneider)-each represents a new host record-and Gaevskajatrema balistes n. sp. was found parasitizing the lower intestine of the Picasso triggerfish, Rhinecanthus assasi (Forsskål). We continue to support synonymy of Gaevskajatrema ponticum (Koval, 1966) Machkevsky, 1990 with Gaevskajatrema perezi (Mathias, 1926) Gibson Bray, 1982, not as a differentiated species. We adopt the restricted posterior extension of the ceca and vitellarium to the testicular zone, without extension of either into the post-testicular space, as diagnostic in distinguishing Gaevskajatrema. Gaevskajatrema balistes n. sp. differs from G. perezi based on its substantially smaller body size with fewer eggs, a longer cirrus-pouch reaching ovarian level and it parasitizes a distinct host group from a structurally and ecologically different ecosystem. Neopycnadena n. gen. is erected for Pseudopycnadena tendu Bray Justine 2007 based on its possessing a large broadly oval cirrus-pouch with a massive field of prostatic cells occupying the entire volume of the cirrus-pouch, a wide, cup-shaped and thick-walled ejaculatory duct, distinct dorsal position of the excretory pore, the bifurcal dextral position of the genital pore, its report from a distinct host group and distant locality and its phylogenetic uniqueness compared with Pseudopycnadena fischthali Saad-Fares Maillard 1986. Neopycnadena n. gen. is ecologically similar to opistholebetines in their life-cycles and morphology; however, phylogenetically separate from opistholebetines as well as from the Polypipapiliotrematinae Martin, Cutmore Cribb in Martin, Sasal, Cutmore, Ward, Aeby Cribb, 2018 and members of Clade [C] of Martin and colleagues, thus we conclude that Neopycnadena n. gen. is unique. Neopycnadeninae n. subfam. is proposed to accommodate Neopycnadena n. gen. We consider that the probable characterization of tetraodontiform specialist taxa (as indicated by the presence of a muscular post-oral ring) and the specificity of the Opistholebetinae Fukui, 1929 sensu stricto with a tetraodontiform host are no longer reliable characters differentiating Gaevskajatrema and Macvicaria Gibson Bray, 1982. The nature of the post-oral structure is discussed and it is adopted to be a diagnostic feature at the generic level among taxa of the Opistholebetinae sensu latu. It is concluded that the expanded concept of the Opistholebetinae is more supported than the restricted one, Birendralebes Srivastava Ghosh, 1972 remains incertae sedis within the Opecoelidae Ozaki, 1925 rather than in the Opistholebetinae, and we provide a generic key to the Opistholebetinae.


Assuntos
Ecossistema , Trematódeos , Animais , Oceano Índico , Filogenia
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