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Despite jellyfish's ecological and socioeconomic impacts, they are still an understudied component of marine ecosystems. Even with its conspicuous size, reaching ~ 1 m in bell diameter, Drymonema gorgo has been rarely observed, with only a few occurrences in the literature, suggesting that it is not a common species. Here, we gathered historical records from literature, personal communication, and novel data from the World Wide Web (WWW) to obtain observations of D. gorgo along the Brazilian coast. A total of 63 observations from 1857 to 2022 were compiled, of which 57 were extracted from the web. Observations on this jellyfish concentrated between 22° S and 27° S, especially in the Cabo Frio region in Rio de Janeiro. They were reported throughout the year, except in August and October, with the highest concentrations in March (late summer). Based on the notable complement on information about its occurrence in the last ten years, we hypothesize that D. gorgo is probably not as rare as suggested by the near absence of previous literature records. In addition, biological associations of D. gorgo with other species were also discovered such as (1) predation on the jellyfish Aurelia sp. and Chrysaora lactea; (2) food item for the green turtle Chelonia mydas; and (3) association with fishes. This study provides evidence of the potential use of the WWW to obtain ecological data about conspicuous marine species occurrence, such as D. gorgo, helping to fill knowledge gaps and overcome difficulties in its detection using traditional methodologies. [ABSTRACT FROM AUTHOR]

Gelatinous animals have been historically viewed as trophic dead-ends. However, there are increasing data showing these organisms being consumed by diverse predators and demonstrate they play an important role in ecosystem functioning. Here we document the Ocypode quadrata (Fabricius, 1787) scavenging on stranded Physalia physalis (Linnaeus, 1758) at Sergipe and Bahia, tropical Brazil (11° and 14° Lat. S), based on Instagram® posts. These findings highlight the potential of social media to complement the information provided by traditional academic sources. We also suggest that this predatory interaction is probably more common than reported in the literature, perhaps due to methodological constraints of stomach content analyses, which may overlook the consumption of gelatinous animals by ghost crabs. [ABSTRACT FROM AUTHOR]

Surface discharges of negatively buoyant jets into moving ambient water create a range of complex flow patterns. These complexities arise through the interplay between the discharge's initial fluxes and the motion of the ambient current. In this study a series of laboratory experiments were conducted for negatively buoyant surface discharges into crossflow to investigate flow patterns under different discharge and ambient conditions. The results compared with simulations of the CORMIX model, an expert system for ocean outfall design. In CORMIX, the simulation module DHYDRO for dense discharges has been used. Finally the flow different patterns were arranged in a dimensionless diagram to propose a modified flow classification system with new criteria. [ABSTRACT FROM AUTHOR]

The evaluation of potential environmental impacts from polycyclic aromatic hydrocarbon is a subject that requires investigation, especially related to emission sources from highway roads with high traffic. In this paper, the distribution of polycyclic aromatic hydrocarbons was investigated in the surface sediments from a subtropical lake, located in the south of Brazil and away from urban areas. The results showed that all sediments presented such compounds in significant concentration, ranging from 9.50 to 29.88 μg/g. The highest total concentration was found in those sites close to the highway (bridges) and the deepest area of the lake. Moreover, a high concentration of polycyclic aromatic hydrocarbons of high molecular weight, such as benzo(a)anthracene and dibenzo(a,h)anthracene was found. It was laso found that high concentrations might be related to asphalt and coal tar pavement used in the highway construction close to the lake. In addition, the potential capacity of sediment toxicity was compared with values of the interim sediment quality guidelines values. The results indicate that most of the sediment presents concentrations of hydrocarbons above these limits. Only fluoranthene and chrysene were found in concentrations below the guideline values. The concentrations of most of the polycyclic hydrocarbons are higher than the quality guidelines. However, the main concern is associated with the presence of benzo(a)anthracene whose concentration is 416 times higher than the limit establisehed by guidelines. The same observation can be done to traces of benzo(a)pyrene and dibenz(a,h)anthracene, with concentration values of 13 and 1,993 times higher. [ABSTRACT FROM AUTHOR]

There are two power generation and seawater desalination plants currently operated at Barka, Oman: Barka I was commissioned in 2003, and Barka II in 2009. The cooling water from the power generation plants are mixed with reject brine (and other effluents) from desalination plants and are discharged through the same marine outfall systems. Therefore, during 2009, the brine discharge plumes changed from the previously positively buoyant from Barka I plant to a newly negatively buoyant from the combined Barka I and II plants. Consequently, instead of rising to the sea-surface, the new brine plume will now tend to sink and stay at the seabed. CORMIX simulations were carried out for two scenarios that represent the previous heated brine discharges and the new concentrated brine discharges from the Barka plants. Due to uncertainty in the input data, further simulations were carried out using salinity as a measure of the plume concentration for single port and multiport, and by varying the ambient current velocity, the effluent discharge density and flow rate. The results show that the water quality standards in the Omani coastal marine environment within the regulatory mixing zone at a 150 m radius from the discharge point have been met for both scenarios. However, the potential benthic impact due to the attachment of the new brine plume at the seabed should be monitored and investigated further. [ABSTRACT FROM AUTHOR]