Search

Estuaries are the main pathway for the microplastics (MPs) to enter into the oceans. However, factors that drive river-sea transport of MPs are not yet fully understood. Therefore, our research investigated the influence of the tidal cycle on the abundance and characteristics of MPs in an urban estuary, through high-frequency sampling (every 2-3 h) using a plankton net (120 μm mesh size) in two seasons (rainy and dry seasons). The results showed that the abundance of MPs decreased during the ebb tide and increased during the flood tide. A positive correlation was found between MP abundance and water height in both seasons. The shapes and colors of MPs varied significantly throughout the tidal cycle. The results show that tides are key agents in the transfer of MPs and cannot be neglected in models of the global contribution of plastic pollution from rivers to oceans., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Identifying the origin of plastic pollution is essential for the development of effective preventive and mitigatory strategies and guidelines for companies, governments, and stakeholders. In 2022, a considerable amount of plastic waste stranded on beaches of the northeastern coast of Brazil. A preliminary analysis of this waste revealed that most of the items were likely foreign made, and a brand auditing approach was applied to identify the brands, parent companies, and potential origin of the plastic waste. The items were also examined to determine their degree of degradation, polymer resin codes, colors, and probable uses. Given their probable foreign origin, a numerical simulation was employed using the OpenDrift dispersion model to determine the likely route each item would have taken before reaching the Brazilian coast. The brand audit confirmed that most of the plastic waste came from Africa (78.5 % of the items), followed by Brazil (15.7 %), and other nations (5.8 %). A total of 31 brands from seven African countries were identified, of which, >90 % originated from the Democratic Republic of the Congo. Drift simulations were consistent with the results of the brand audit, indicating that the plastics originated from the west coast of African, primarily between latitudes 5° N and 10° S. This analysis indicated that the Congo river was the principal source of the plastic waste that found its way to the Brazilian beaches. The present study highlights the widespread occurrence of plastic pollution across the Atlantic Ocean and underscores the need for mitigatory and regulatory measures that consider foreign sources, as well as local drivers of pollution. In this context, continuous monitoring programs will be essential to advance our understanding of the magnitude of the international plastic pollution problem, and provide insights to delineate specific enforcements dealing with this issue., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In the present study, we applied forensic geochemistry to investigate the origin and fate of spilled oils like tarballs stranded at the beaches of Bahia, in northeastern Brazil, in September 2023, based on their fingerprints. Saturated and aromatic compounds were assessed by gas chromatography, and the oceanic surface circulation patterns were deciphered to determine the geographic origin of the spill. Contamination by petroleum represents an enormous threat to the unique, species-rich ecosystems of the study area. The geochemical fingerprint of the oil spilled in 2023 did not correlate with those of previous events, including the one in 2019, the one in early 2022 in Ceará, and an extensive spill across the Brazilian Northeast in late 2022. However, the fingerprint did correlate with crude oils produced by Middle Eastern countries, most likely Kuwait. The oil of the 2023 spill had a carbonate marine origin from early mature source rocks. These findings, together with the moderate weathering of the 2023 tarballs and the ocean circulation patterns at the time of the event, indicate that the oil was discharged close to the shore of Brazil, to the east or southeast of Salvador, by a tanker on an international route in the South Atlantic.

Anthropogenic marine debris and invasive species are pervasive in the ocean. However, research on the mechanisms and dynamics controlling their distribution in marine systems (e.g.; by floating debris acting as vectors for invasive species) is limited. Applying a numerical modeling approach, we demonstrate that rafting invasive corals (Tubastraea spp.) can be transported over long distances and reach important tropical receptor regions. In <180 days, buoyant debris can cover distances between 264 and 7170 km moving from the Brazilian semiarid coast to the Amazon coast and reaching eight regions in the Wider Caribbean (mainly the Eastern Caribbean and Greater Antilles). Analyzing 48 simulated scenarios (4 years × 3 depths × 4 months), we demonstrate that in ~86 % of the scenarios the particles are stranded in the Caribbean and in ~71 % they end up in the Amazon coast. Our results showed litter floating trajectories at 0-10 m water depth, transported every year to the Caribbean province. However, in August this transport is frequently blocked by the retroflection of the North Brazil Current adjacent to the Amazon River estuarine plume. Our results indicate routes for fast and long-distance transport of litter-rafting invasive species. We hypothesized a high risk of bioinvasion on important marine ecosystems (e.g., coral reefs) likely becoming increasingly threatened by these invasive species and debris. This highlights the imperative need for an ocean governance shift in prevention, control, and eradication, not only focused on local actions to prevent the spread of invasive species but also a broad international action to decrease and mitigate marine debris pollution globally., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Coral reefs in turbid waters have been hypothesized to be a refuge from climate change. These naturally occurring communities were brought into the spotlight because some of their species exhibited record levels of resistance to marine heatwaves (MHWs) by disturbance-tolerant corals. However, long-term monitoring data on the drivers of coral bleaching in these extreme reef habitats are scarce. Here, we describe the population structure and bleaching rates of a widespread and resilient coral (Siderastrea stellata). We examine the links between environmental factors, namely, rainfall, wind speed, turbidity, solar irradiance, sea surface temperature, MHWs, and coral bleaching status under the worst recorded drought cycle in the Tropical South Atlantic (2013-2015). We examined 2880 colonies, most of which (∼93%) fit in the size group of 2-10 cm, with a small number (∼1%) of larger and older colonies (>20 cm). The results indicated the absence of MHWs and normal sea surface temperature variations (between 26.6 °C and 29.3 °C), however, we detected an extreme rainfall deficit (30-40% less annual volume precipitation). In general, a high proportion (44-84%) of bleached colonies was found throughout the months when turbidity decreased. Siderastrea is the only reef-building coral that comprises this seascape with encrusting and low-relief colonies. During drought periods, cloudiness is reduced, turbidity and wind speed are reduced, and solar irradiance increase, driving coral bleaching in turbid reefs. However, episodic rainfall and higher wind speeds increase turbidity and decrease coral bleaching. Our hypothesis is that turbidity decreases during drought periods which increases bleaching risk to corals even without thermal stress. Our results suggest that turbidity may have related to wind and rainfall to provoke the coral bleaching phenomenon., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Large gaps in reef distribution may hinder the dispersal of marine organisms, interrupting processes vital to the maintenance of biodiversity. Here we show the presence and location of extensive reef habitats on the continental shelf between the Amazon Reef System (ARS) and the Eastern Brazilian Reef System (ERS), two reef complexes off eastern South America. Formations located 20-50 m deep include both biogenic and geogenic structures. The presence of diverse reef assemblages suggests the widespread occurrence of rocky substrates below 50 m. These habitats represent an expansion of both the ARS and ERS and the closure of the only remaining large-scale gap (~ 1000 km) among West Atlantic reef environments. This indicates that the SW Atlantic harbors a single, yet heterogeneous, reef system that stretches for about 4000 km, and thus, represents one of the largest semi-continuous tropical marine ecosystems in the world., (© 2022. The Author(s).)

This article presents a synthesis of information about the massive oil spill in Brazil (2019/2020). The event affected 11 states; however, the majority of the oil residue was collected (~ 5380 tons) near nine states (99.8%) in northeastern Brazil. This spill was not the largest in volume (between 5000 m 3 and 12,000 m 3 ) recorded in tropical oceans, but it was the most extensive (2890 km). This spill develops an overwashed tar that remains mostly in the undersurface drift (non-floating oil plume) below 17 m of depth while on the continental shelf. Ten ecosystems were impacted, with potentially more severe effects in mangroves and seagrasses. Certain negative effects are still understudied, such as effects on tropical reefs and rhodolith beds. A total of 57 protected areas in seven management categories were affected, most of which (60%) were characterized as multiple-use regions. The spill affected at least 34 threatened species, with impacts detected on plankton and benthic communities. Acute impacts were reported on echinoderms, coral symbionts, polychaetes, and sponges with evidence of oil ingestion. Socioeconomic impacts were detected in food security, public health, lodging, gender equality, tourism, and fishing, with reduced sales, prices, tourist attractiveness, gross domestic product, and employment. Moreover, chemical contamination was detected in some states by toxic metals (Hg, As, Cd, Pb, and Zn) and polycyclic aromatic hydrocarbons (acenaphthalene, fluoranthene, fluorene, naphthalene, and phenanthrene). This summary aims to aid in the design of science-based strategies to understand the impacts and develop strategies for the most extensive spill observed in tropical oceans., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

In 2018, unidentified packages appeared along approximately 1600 Km of the Brazilian coastline causing widespread pollution to beaches and danger to society. The packages were found to be bales of raw rubber ranging in size from 0.06 m³ to 3.4 m³ and weighing up to 200 kg. A few bales were marked with the stamp "Product of French Indochina" and colonized by the barnacle Lepas anatifera, an oceanic species. We found that unidentified packages are from a Second World War (WWII) shipwreck, and that the source is almost certainly the SS Rio Grande found at 5,762 m depth. Numerical simulations show that currents can carry out the bales from the SS Rio Grande to the beaches. We highlight transnational measures to study and protect the WWI shipwrecks because they represent an overlooked environmental risk., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The objective of this study was to report, for the first time, the presence of an invasive coral (Tubastraea tagusensis) in an oil platform on the Brazilian equatorial continental shelf. This structure is located more than 1200 km north from other oil and gas structures colonized by this coral. We also discussed the retirement and decommissioning of old biofouling-encrusted oil and gas platforms (~62 platforms) from decreased production and the current oil crisis, exacerbated by the COVID-19 pandemic. This presents an ecological concern due invasive coral range expansion and potential impacts to poorly studied ecosystems such as marginal shallow-water coral reefs and mesophotic ecosystems. It is imperative that mindful risk analysis and rigorous environmental studies must precede the installation of new oil and gas platforms. In addition, decommissioning of retired structures should take into consideration marine restoration and non-indigenous species dispersal, and more specifically, Tubastraea bioinvasion., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The aim of the present study was to perform the first assessment of the abundance and classification of marine debris as well as determine the sources, transport and fate of this debris on an urbanized coast with multiple human activities. More than 80% of the marine debris was composed of synthetic materials. The beached marine debris was classified according to size. Meso-debris accounted for the highest portion of contamination (55%), followed by macro-debris (25.1%) and small debris (19.9%). Contamination by debris, such as cotton swabs (31%) and lollipop sticks (36.8%) accounted for the largest portion of the small debris class. Human recreational activities were the predominant source of debris, followed by navigation/fishing activities, domestic activities and industrial/port activities. The assessment of the predominance of human activities and the results of the model revealed a larger contribution of debris from recreational activities on nearby beaches on the small to larger scale and that rivers exert less of an influence due to the fact that they do not flow the entire year., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Copyright of Botanical Review is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Atlantic reef-building corals and coral reefs continue to experience extensive decline due to increased stressors related to climate change, disease, pollution, and numerous anthropogenic threats. To understand the impact of ocean warming and reef loss on the estimated extinction risk of shallow water Atlantic reef-building scleractinians and milleporids, all 85 valid species were reassessed under the IUCN Red List Categories and Criteria, updating the previous Red List assessment of Atlantic corals published in 2008. For the present assessment, individual species declines were estimated based on the modeled coral cover loss (1989–2019) and projected onset of annual severe bleaching events (2020–2050) across the Atlantic. Species traits were used to scale species' relative vulnerability to the modeled cover declines and forecasted bleaching events. The updated assessments place 45.88%–54.12% of Atlantic shallow water corals at an elevated extinction risk compared to the previous assessments conducted in 2008 (15.19%–40.51%). However, coral cover loss estimates indicate an improvement in reef coverage compared to the historic time-series used for the 2008 assessments. Based on this, we infer that, although remaining dangerously high, the rate of Atlantic reef coral cover decline has surprisingly slowed in recent decades. However, based on modeled projections of sea-surface temperature that predict the onset of annual severe bleaching events within the next 30 years, we listed 26 (out of 85) species as Critically Endangered in the IUCN Red List. Each of these species had previously been listed under a lower threatened category and this result alone highlights the severe threat future bleaching events pose to coral survival and the reef ecosystems they support. [ABSTRACT FROM AUTHOR]

Road corridor vegetation plays a vital role in maintaining ecosystem stability and providing essential ecological services, particularly in semi-arid regions where environmental conditions are challenging. In this study, we investigated the functional traits of native and non-native plant species along the N5 highway corridor in the semi-arid region of Punjab, Pakistan. The methodology involved extensive field surveys and systematic sampling of herbaceous vegetation, followed by detailed measurements of functional traits diversity. We classified 38 plant species into native and non-native categories and analyzed their distribution, life forms, leaf spectra, and flowering phenology. Our results revealed distinct patterns in the functional traits of native and non-native species, with non-native species exhibiting larger plant heights, leaf sizes, and leaf surface areas compared to native species. Additionally, native species displayed greater root and stem biomass, indicative of adaptations to nutrient-poor soils and water-limited environments. The findings suggest that non-native species possess traits associated with rapid growth and resource acquisition, enabling them to outcompete native vegetation and establish dominance in roadside ecosystems. These results provide valuable insights for understanding the ecological implications of non-native species and designing effective management strategies to mitigate their impacts on native biodiversity and ecosystem resilience in semi-arid regions. [ABSTRACT FROM AUTHOR]

Regardless of the specific technology adopted, the use of desalination to produce fresh water from seawater results in a discharge of brine effluent containing a high concentration of salts and other desalination by-products that must be dealt with appropriately. Until now, this effluent has most commonly been discharged into the sea through a submarine outfall. Computational tools are used to simulate the behavior of these brine discharges to minimize their impact on the marine environment. Environmental assessments of desalination plants that are made using these tools can include consideration of the rates of effluent production and flow, diffuser configurations, marine conditions (e.g., currents, tides, salinity, temperature), and the proximity of plants to environmentally significant areas. Computational tools can also assist in the design of programs for monitoring the surroundings of brine disposal points. In this study, we developed a new tool for modeling brine discharges from submarine outfalls based on an adaptation of a near-field mathematical model coupled with a Lagrangian model. This new model was specifically designed for application to negatively buoyant effluent discharges. The near-field dilution results that were obtained for various current velocities and different diffuser vertical inclinations using this tool were compared with those obtained using a reference tool (Visual Plumes), considering four different desalination plants. Excellent correlation and a mean absolute percentage error lower than 10% were obtained between the two sets of results along with good reproducibility. Additionally, the existence of an integrated wave propagation model in the simulation software allowed the analysis of changes in the brine plume direction produced by waves formed far from the outfall area. Using the new model, it was possible to evaluate how the diffuser configuration affected the performance of the diffuser line, and the saline plume generated by the combined Lagrangian and near-field model realistically reproduced the behavior of a submarine brine outfall. This combined model is potentially applicable to a range of other situations, including studies that aim to minimize the environmental impact of desalination plants based on considerations of outfall locations and optimization of the diffuser configuration. [ABSTRACT FROM AUTHOR]

Brazil, a vital pineapple producer, faces phytosanitary challenges, mainly due to fusariosis caused by Fusarium guttiforme, which can lead to significant harvest losses. The frequent use of chemical fungicides has disadvantages because they are environmental contaminants. One option to avoid using these compounds is essential oils, which are of natural origin, biodegradable and have notable activity in controlling numerous pathogens. Thus, the present research aimed to evaluate in vitro the potential of citronella essential oil to control the fungus F. guttiforme. The chemical identification of the essential oil components was conducted using gas chromatography with flame ionization detectors and mass spectrometry. The main compounds identified in citronella essential oil were citronellal (35.70%), geraniol (24.63%) and citronellol (15.98%). It was clear that the concentration of 1.050 μL mL−1 of citronella essential oil promoted 100% inhibition of mycelial growth, with no statistically significant difference when compared to the positive control (Tecto® SC). These results confirm citronella essential oil's remarkable in vitro potential in controlling the fungus F. guttiforme. [ABSTRACT FROM AUTHOR]

In mid-2018, several neighbourhoods in Maceió, Brazil, were affected by soil subsidence in the region. Since then, unprecedented developments and consequences have been observed in the affected areas. Against this backdrop, the study aims to analyses the socio-environmental impacts suffered by the five neighbourhoods affected by subsidence from rock salt extraction in the municipality of Maceió, Alagoas, Brazil. We collected secondary data from documents (Geological Survey studies, information made available by the Federal Public Prosecutor's Office, Compensation Plan, Terms of Agreement, Socio-urban Action Plan, Environmental Impact Study, Study of the Economic Impact of the Disaster) to assess the socio-environmental impacts caused by the socio-environmental disaster. These data were analysed using Checklist, Interaction Matrix, and Delphi. The results highlight the complexity of the effects since they were observed from a multidisciplinary approach. In addition, it is clear that these impacts were relevant and important from the specialists' point of view and, when analysed quantitatively and qualitatively,such as impacts on identity and cultural aspects, change in standard of living, and overload in the provision of public facilities, which had a high degree of impact when evaluated in this study. The study also concluded that it is pertinent to take measures to mitigate the impacts indicated as possible through integration between public authorities and the mining company. Upon its completion, a technical product in the form of a document containing the identified mitigation measures was submitted to the competent authorities. These results can be relevant for practitioners and policymakers involved in decisions related to mining operations. [ABSTRACT FROM AUTHOR]

Pesticide contamination remains a significant environmental concern globally, with important implications for aquatic ecosystems. Despite being one of the world's largest pesticide consumers, monitoring and assessment of pesticide pollution are limited in Brazil, especially in sensitive regions like the Amazon. In this study, the occurrence and environmental risks of 8 pesticides of different classes, namely alachlor, atrazine, chlorfenvinphos, isoproturon, irgarol, simazine, diuron, and its transformation product DCPMU (1-(3,4-dichlorophenyl)-3-methyl urea) were analysed in surface water of the São Marcos Estuarine Complex (SMEC) in two consecutive years. The quantification of the target compounds was performed using ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS). Suspected and untargeted screening analyses with ultra-high-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) was also conducted to identify transformation products (TPs) and additional pesticides in water samples. All target pesticides, except for alachlor, were found in at least one sampling campaign. The antifouling biocides irgarol and diuron were ubiquitous in 2018 and 2019, with detection frequencies varying between 81 and 100% and maximum concentrations of 13.6 ng L -1 and 17.1 ng L -1 , respectively. In 2019, the detection frequencies of the target pesticides were considerably higher than in 2018, with atrazine, isoproturon, and DCPMU being found in 100% of the samples. In 2019, chlorfenvinphos and isoproturon were the pesticides with the highest levels, reaching 48.6 ng L -1 and 44.6 ng L -1 , respectively. The UHPLC-HRMS analysis showed the presence of the pesticides DEET (N,N-diethyl-meta-toluamide), octhilinone (2-Octyl-4-isothiazolin-3-one), and cyprodinil (4-cyclopropyl-6-methyl-N-phenylpyrimidin-2-amine) in water samples. Additionally, the TPs 2-hydroxy-atrazine, didemethylisoproturon (1-(4-isopropylphenyl)urea) and M1 (2-methylthio-4-tert-butylamino-6-amino-s-triazine) were found. The environmental risk assessment showed that irgarol was the primary contributor to the global risk quotient in the SMEC region. Similarly, chlorfenvinphos also showed a high risk to the local aquatic biota, especially in 2019. This research not only highlights the urgent need for improved pesticide monitoring in Brazil but also establishes a baseline for future studies and environmental management efforts in SMEC. We emphasize the importance of prioritising pollutants and implementing effective mitigation strategies to protect the fragile aquatic ecosystems of the Brazilian Amazon., Competing Interests: Declarations. Ethical approval: Not applicable. Consent to participate: All authors have given consent to participate in this manuscript. Consent for publication: All authors agree with the publication of the manuscript. Competing interests: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

This study evaluated the effects of water-soluble fractions (WSF) of stranded oil sampled from the beaches of Trancoso and Massarandupió (Bahia, Brazil) following a mysterious oil spill along Brazil's northeast coast (2019-2020). The samples were characterized for aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs) and tested for chronic toxicity in the embryo-larval stages of the sea urchin Echinometra lucunter. The WSFs contained high levels of PAHs, some of which were above the acceptable levels for water in Brazil, and toxicity to sea urchin embryos tended to occur at higher concentrations., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Plastic materials have many destinies on the environment, and one of them is its continuous fragmentation, originating microplastics (MP). MP act as an adsorption surface for organic pollutants like polycyclic aromatic hydrocarbons (PAH). Due to its toxic and harmful properties, 16 PAH are defined as priorities in studies. Several works have evaluated the occurrence of MP and PAH individually in environmental matrices, but just a few have investigated their association. The present study aims to investigate PAH occurrence, sources, and concentration in MP from beach sediments of eight Brazilian coastal states. Sixteen PAH were analyzed by gas chromatography, in which 14 PAH were detected, and PAH total concentration (ΣPAH) ranged from 0.25 to 71.60 ng g−1. In the North and Northeast regions, the low PAH concentrations in MP appear to be related to the intense hydrodynamic processes. Naphthalene levels on the Styrofoam were above the threshold effect level in two samples and near it on one; therefore, effects in the organisms might occur due to these PAH. The Southeast and South regions are the only ones with previous studies relating PAH with MP, and ΣPAH ranged from 0.34 to 2.52 ng g−1. According to the diagnostic ratios, the PAH sources were associated with industrial and port activities, untreated effluent disposal, and urban runoff by pluvial waters. The highest ΣPAH level was found in the Styrofoam samples, suggesting that this MP type might contribute considerable to PAH dispersion on Brazilian coast beaches. [ABSTRACT FROM AUTHOR]

We evaluated how fish assemblages in estuaries on the semiarid coast of Brazil are impacted taxonomically and functionally under two contrasting events: prolonged drought vs. ample precipitation. The fish fauna of six local estuaries was sampled, three under each event. The species composition of the two groups was compared using non-metric multidimensional scaling, permutational multivariate analysis of variance, and similarity percentages analysis. The functional structure was described using principal coordinate analysis and expressed as functional richness (FRic) and functional dispersion (FDis). We also ran extinction simulations to estimate how the most functionally original (FOri) and specialized (FSpe) species contributed to functional structure (FRic, FDis). Estuaries exposed to prolonged drought displayed greater abundance of marine stragglers and marine migrants and higher FRic values than did estuaries exposed to ample precipitation. They also suffered smaller losses in FRic when the most original and specialized species were removed. No clear pattern was discernible for FDis. In short, prolonged drought was associated with changes in the taxonomic and functional structure of the fish fauna in the sampled estuaries through the process of 'marinization.' Monitoring these ecosystems can predict changes in salinity associated with long-term global climate trends and their effects on the fish fauna. [ABSTRACT FROM AUTHOR]

Continental shelves encompass gently sloped seascapes that are highly productive and intensively exploited for natural resources. Islands, reefs and other emergent or quasi-emergent features punctuate these shallow (<100 m) seascapes and are well known drivers of increased biomass and biodiversity, as well as predictors of fishing and other human uses. On the other hand, relict mesoscale geomorphological features that do not represent navigation hazards, such as incised valleys (IVs), remain poorly charted. Consequently, their role in biophysical processes remains poorly assessed and sampled. Incised valleys are common within rhodolith beds (RBs), the most extensive benthic habitat along the tropical and subtropical portions of the mid and outer Brazilian shelf. Here, we report on a multi-proxy assessment carried out in a tropical-subtropical transition region (~20°S) off Eastern Brazil, contrasting physicochemical and biological variables in IVs and adjacent RBs. Valleys interfere in near bottom circulation and function as conduits for water and propagules from the slope up to the mid shelf. In addition, they provide a stable and structurally complex habitat for black corals and gorgonians that usually occur in deeper water, contrasting sharply with the algae-dominated RB. Fish richness, abundance and biomass were also higher in the IVs, with small planktivores and large-bodied, commercially important species (e.g. groupers, snappers and grunts) presenting smaller abundances or being absent from RBs. Overall, IVs are unique and vulnerable habitats that sustain diverse assemblages and important ecosystem processes. As new IVs are detected by remote sensing or bathymetric surveys, they can be incorporated into regional marine management plans as conservation targets and priority sites for detailed in situ surveys. [ABSTRACT FROM AUTHOR]

Reef corals have been threatened by climate change, with more frequent and intense bleaching events leading to extensive coral mortality and loss of coral cover worldwide. In the face of this, the corals' photosymbiont assemblages have received special attention as a key to better understand the bleaching process and its recovery. To assess the effects of thermal anomalies, the coral Mussismilia harttii and the hydrocoral Millepora alcicornis were monitored through the El Niño 2015/2016 at a Southwestern Atlantic (SWA) coral reef. A severe bleaching event (57% of colonies bleached) was documented, triggered by a < 3 °C-week heatwave, but no mortality was detected. The hydrocoral was more susceptible than the scleractinian, displaying bleaching symptoms earlier and experiencing a longer and more intense bleaching event. The composition of photosymbionts in the M. alcicornis population was affected only at the rare biosphere level (< 5% relative abundance), with the emergence of new symbionts after bleaching. Conversely, a temporary dysbiosis was observed in the M. harttii population, with one of the dominant symbiodiniaceans decreasing in relative abundance at the peak of the bleaching, which negatively affected the total β-diversity. After colonies' complete recovery, symbiodiniaceans' dominances returned to normal levels in both hosts. These results highlight critical differences in how the two coral species cope with bleaching and contribute to the understanding of the role of photosymbionts throughout the bleaching-recovery process. [ABSTRACT FROM AUTHOR]

Copyright of Neotropical Ichthyology is the property of Neotropical Ichthyology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Invasive species stimulate science through problem-oriented research but only a small portion of studies have discussed the impacts of biological invasions upon the science itself. Three of the ten currently recognized species of the coral genus Tubastraea are invasive and have attracted substantial research attention. Using a bibliographic survey and bibliometric approach we synthesized knowledge to examine if invasion events lead to an increase and intensification of research not mirrored in the native range. More than twice as many studies of the genus were performed in the nonnative ranges than native, most being original research recently published in the conventional literature. Brazil and the United States of America (Gulf of Mexico) (nonnative range) were most studied with oil and gas platforms the main (49%) focus of pathway and vector research. Ecological processes such as recruitment, survivorship, larval settlement, and population abundance and structure, were proportionally more studied in nonnative ranges, as were competitive interactions. This synthesis of the set of knowledge that is available about Tubastraea spp. demonstrates that invasion biology is a highly pragmatic science and as the genus has expanded its range through the world the scientific community has increasingly focused its attention on the invasion which has provided science, management and stakeholders with a wide body of information on many basic and applied aspects of the biology and ecology of the species. [ABSTRACT FROM AUTHOR]

Lignocellulose is a kind of renewable material with stable structure and abundant reserves. The superhydrophobic lignocellulose composites prepared by one-pot method in this study had the advantages of pollution-free, stable structure and simple processes. The prepared superhydrophobic lignocellulose composites exhibited superhydrophobic-superoleophilic wettability, with a water contact angle (CA) of 157° ± 3.6° and an oil CA of about 0°. Abrasion and ultraviolet (UV) radiation experiments demonstrated that the prepared composites had good mechanical stability and UV resistance. In addition, the composites presented an ultra-fast oil absorption rate and high oil-water separation efficiency of more than 96% for various types of oil-water mixtures. And the maximum oil flux was greater than 6500 L·m−2h−1bar−1. Such superhydrophobic lignocellulose composites hold great application prospects in the field of oil-water separation. [ABSTRACT FROM AUTHOR]

The impacts of the 2019 Brazilian coast oil spill on mesozooplankton community were investigated using data of before and after spill off the coast of Salvador. The presence of oil droplets was detected in all samples collected in the continental shelf of Salvador, after oil spill (Oct/2020). The total density of oil droplets ranged from 5.03 to 20.37 droplets m–3. The size of oil droplets found this study was similar to natural size of zooplankton foods. The highest percentages of oiled copepods 0.09% and 0.02% were recorded in stations BA1 and BA2 (closest to the coast), respectively. The presence of crude oil droplets was confirmed by the observation of crude oil fluorescence under UVA illumination. Zooplankton assemblage structure exhibited a significant reduction in the taxa number after oil spill. Seven copepods species were registered only before oil spill (Oct/2013, Feb/2014), and during October 2020 were registered 10 fewer species. The total zooplankton density varied from 38.2 to 110.4 org m−3 (October/2013), 87.1 to 803.2 org m−3 (February/2014), 9.4 to 27.4 org m−3 (October/2020) and 17.6 to 45.6 org m−3 (February/2021). The average density values for the period before spill were up to 10 times higher than the average value found after spill. The Analyze of Similarity used in this study revealed that zooplankton assemblages in the continental shelf of Salvador showed changes in its structure after the accident on the Brazilian coast, particularly on October 2020. Overall, our results indicate negative impact of oil spill in the coastal region of Brazil Northeaster on structure of zooplankton assemblages in the continental shelf of Salvador. [ABSTRACT FROM AUTHOR]

This study evaluated the presence of plastics and microplastics in macrophytes in an urbanized sector of the Amazon River. A total of 77 quadrats in 23 macrophyte banks were sampled during the dry (September 2020) and rainy (June 2021) season. Five species were identified: Paspalum repens, Pontederia rotundifolia, Pistia stratiotes, Salvinia auriculata and Limnobium laevigatum, with P. repens being dominant during the dry season (47.54%) and P. rotundifolia during the rainy season (78.96%). Most of the plastic particles accumulated in Paspalum repens (49.3%) and P. rotundifolia (32.4%), likely due to their morphological structure and volume. The dry season showed a higher accumulation of plastic particles than the rainy season. Microplastics were found in most samples, during both the dry (75.98%) and rainy seasons (74.03%). The upstream macrophyte banks retained more plastic particles compared to the downstream banks. A moderate positive correlation was observed between the presence of plastic particles and macrophyte biomass, and a weak positive correlation between the occurrence of microplastics and mesoplastics. White and blue fragments, ranging from 1 to 5 mm were the most common microplastics found in the macrophyte banks. Green fragments and green and blue fibers were identified as polypropylene, blue and red fragments as polyethylene, and white fragments as polystyrene. Therefore, the results of this study highlight the first evidence of the retention of plastic particles in macrophytes of the Amazon and highlight a significant risk due to the harmful effects that this type of plastic can cause to the fauna and flora of aquatic ecosystems., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Invasive sun corals (Tubastraea spp.) are spreading along the Brazilian coast where they compete for space with native species, produce chemical compounds with antifouling and anti-predation properties and modify community structure and function. The tropical rocky shores of the Ilha Grande Bay were the first to be invaded in the southwest Atlantic and the Tamoios Marine Protected Area (MPA) within the bay was directly in the path of the spread of Tubastraea. MPAs aim to conserve biodiversity, preventing habitat loss and fragmentation and maintain healthy ecosystems. As healthy communities might better resist invasion the aim of this study was to investigate to what extent the benthic communities of the MPA are resisting the invasion. Baseline data on the abundance of the invasive corals Tubastraea spp. and community structure (cover) were quantified at eight sites over six years. The benthic communities were dominated by multispecies algal turfs, the mat-forming zooantharian Palythoa caribaeorum and the red alga Asparagopsis taxiformis and fell into five community groups two of which contained Tubastraea spp. The number of invaded sites increased over time as did the abundance of Tubastraea spp. in the communities. Tubastraea spp. sequentially invaded the studied communities within the MPA independently of differing community compositions - i.e. they did not offer better biotic resistance than unprotected areas. This was facilitated by the patchy nature of the communities which allowed Tubastraea spp. to get a foothold by initially avoiding species such as P. caribaeorum which offer greater biological resistance. At one site a significant reduction in Tubastraea spp. was detected after mechanical control. We conclude that the MPA's status as a conservation unit was important to attract research and thus for establishing a baseline, quantifying change due to the invasion and focusing limited management resources, but not in providing significant biotic resistance to the invasion. [ABSTRACT FROM AUTHOR]

Adequate methods to evaluate the extension of global and local damage on coral reefs, and to minimize it, are urgent. The Tropical Southwestern Atlantic reefs are partially protected by Marine Protected Areas (MPA) that apply spatial zoning as a management strategy. A resilience-based management approach was used to evaluate the effectiveness of no-take areas in improving reef resilience, inside the largest coastal MPA of Brazil. Ecological indicators were used to calculate resilience scores, to test the hypothesis that no-take reefs present higher resilience than tourism reefs. Score values indicated medium–high resilience for both. Despite the similar values, the contribution of the indicators to the score varied between reefs. Herbivorous fish biomass was the main indicator influencing higher scores. Management through spatial zoning and the compliance of this regulation raised the resilience of coral reefs. The main management actions recommended are the creation of no-take areas in coastal habitats such as mangroves and seagrass beds. [ABSTRACT FROM AUTHOR]

The introduction of non-native fish poses a major threat to aquatic fauna in freshwater ecosystems around the world, often as a consequence of increased predation pressure, which results in adverse environmental and socioeconomic effects. In this study, we present a survey of publicly available information on the occurrence of pirarucu (Arapaima spp.) throughout Brazil, with an emphasis on the status of native and non-native populations, and discuss the implications for the conservation of aquatic biodiversity and the urgent need for strict control and monitoring of pirarucu breeding programs, especially in regions where it is non-native. We believe that researchers and public policy makers/managers should collaborate in managing introductions of non-native fish, and develop regulations, scientific research, risk assessments, and environmental education with this end in mind. [ABSTRACT FROM AUTHOR]

Petroleum oil leakage and industrial oily waste on the water surface are sustainable pollutions. The removal process by eco-friendly adsorbents is a critical challenge. It also requires sustainable treatment. The natural hydrophobic material such as abietic acid, boswellic acid, and chitosan was added to magnetite nanoparticles with different concentrations of 10, 15, and 20% on its surface. The magnetite acquires partially hydrophobic properties. The prepared natural adsorbents were analyzed by employing wide-angle X-ray diffraction (WAXD), vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), particle size and zeta potential, and contact angle measurements. Chitosan adsorbs at the outer surface of magnetite nanoparticles while boswellic and abietic absorb in bulk. All prepared adsorbents are effective in adsorbing waste oil from the water surface. The contact angle of MB20 (magnetite/20 percent boswellic) is greater than that of MA20 and MC20 (magnetite/20% abietic or chitosan, respectively), indicating that it has more hydrophobic characteristics. The oil removal efficiency and adsorption capacity of MB20 are the highest values 57.6%, and 24 g/g, respectively. All eco-friendly adsorbents are nontoxic with low-cost production and are used many times. [ABSTRACT FROM AUTHOR]

The aim of the present study was to perform morphological and chemical characterizations of microplastics (MPs) found in seawater samples from the coast of the city of Fortaleza (CE) using Fourier-transform infrared (FTIR) spectroscopy, Raman spectroscopy and differential scanning calorimetry (DSC). Sampling was performed using a neuston sampler. MPs were separated based on the difference in density. MPs with varied morphologies were found. Fibers and fragments were the most abundant (57% and 36.2%, respectively). FTIR, Raman spectroscopy and DSC confirmed the presence of polyurethane and alkyd resin, polyethylene, polypropylene, polystyrene, polyamide blends, thermoplastic rubber and polyester fibers. The main sources of MPs and their relative contribution were fishing activities, food packaging and household products with 55.1%, household laundry with 27.2%, wear of surface coatings with 10.0% and wear of automobile tires with 7.6%. As a result, polyethylene, polypropylene, polystyrene and polyamide are believed to enter the marine environment mainly through fishing activities and debris from food packaging, polyester mainly through domestic sewage contaminated by washing clothes fibers, polyurethane and alkyd resin from the abrasive wear of surface coatings, as well as rubber particles from the wear of the automobile tires. Thus, one may infer that the main sources of MPs in the marine environment on the coast of Fortaleza are anthropogenic activities. Additionally, there is less information on blends and weathered MPs in commercial polymer databases. Therefore, the MP spectra obtained in this study can serve as a database to compare and characterize these more complex MPs. [ABSTRACT FROM AUTHOR]

This work investigates the impact of regional climatic changes upon the salinity field of Todos os Santos Bay (BTS), the third largest estuary in the country. A comprehensive meteorological and oceanographic data set was used, which included more than 50 years of rainfall, river discharge and air temperature, 7 years of hydrodynamic numerical simulations of the bay and adjacent shelf, and 3 years of observations of the salinity field. The results show a clear aridification (less humidity and warmer air temperatures) trend in the last 5–6 decades. In this period, the yearly mean fluvial discharges and total rainfall were reduced by up to 72% and 50%, respectively, of their climatological means, and the air temperature increased by up to 1.25 °C. Less freshwater inflow and higher temperatures caused an increase of the mean surface salinity of 0.6 for the whole bay and 1.2 in the most internal sectors. Hypersalinity events apparently occurred for the first time in the early 1990s, and reached a maximum intensity in 2013 during the worst regional draught in the historical record, when an estuarine density plug was observed. The hypersalinity events were intensified, and not caused by the damming of Paraguaçu River, whose summer discharges have decreased faster than anticipated by previous investigations. The original tropical climate of the region has become more Mediterranean, with relatively less rainfall occurring in the summer. The hydrographic changes of the BTS exemplify similar hydrological and hydrographic processes that might also be underway in tropical areas undergoing climate aridification. [ABSTRACT FROM AUTHOR]

Oil spills into the oceans cause irreparable damage to marine life and harms the coastal population of the affected areas. The main measures to be taken in response to an oil spill are to reduce the impact on marine life, prevent oil from reaching the shore through its recovery, and accelerate the degradation of unrecovered oil. Any environmental damage can be reduced if the spilled oil is removed from the water quickly and efficiently. Therefore, it is essential to know the treatment strategies for spilled oils. Several technologies are currently available, including booms, skimmers, in situ burning, use of adsorbents, dispersants/surfactants, and bioremediation. The selection of the type of treatment will depend not only on the effectiveness of the technique, but mainly on the type of oil, amount spilled, location, weather, and sea conditions. In this review, the characteristics of oil spills, their origin, destination, and impacts caused, including major accidents around the world, are initially addressed. Then, the main physical, chemical, and biological treatment technologies are presented, describing their advances, advantages, and drawbacks, with a focus on the use of green surfactants. These agents will be described in detail, showing the evolution of research, recent studies, patents, and commercialized products. Finally, the challenges that remain due to spills, the necessary actions, and the prospects for the development of existing treatment technologies are discussed, which must be linked to the use of combined techniques. [ABSTRACT FROM AUTHOR]

Copyright of Universitas Scientiarum is the property of Pontificia Universidad Javeriana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For the Amazon, it is important to encourage the production of native fish, since there are several species of zootechnical interest. For this, it is necessary to know the species since its acquisition, production, processing, and marketing. Therefore, the aim of this study was to analyze the yield, correlations, and profitability of different cuts of black pacu (Colossoma macropomum) in five weight categories. Data from 220 black pacus were obtained, with a weight range of 2725 ± 1975 g. Yields of commercial cuts and morphometric measurements were evaluated in five weight classes. Kruskal-Wallis test (α = 0.05) was used to compare the average income. And, to verify the correlation between the morphometric measures and the yields, Spearman's correlation was performed (α = 0.05). To obtain the profit of the weight classes due to the cut produced, an economic analysis was carried out considering the cost of buying the fish. Yields of fillet, ribs, and steak were higher in classes 3 and 4, while in the same classes, the yield of residues was the lowest. Despite classes 1, 2, and 5 showing lower yields, the economic analysis presented that the production of fillet and ribs was profitable. The measures of total length and standard length have a high positive correlation with the yield of meat in all classes, as well as the average circumference and caudal circumference in classes 1, 2, and 4, which can be used to determine the yields of this commercial cut. [ABSTRACT FROM AUTHOR]

Mercury (Hg) contamination has caused ecological and socioeconomic problems worldwide. One of the main Hg contamination routes by the human populations is through fish ingestion. Herein, we analyzed the total Hg concentrations (THg) in highly consumed marine fish species: Brazilian flathead Percophis brasiliensis, Atlantic bigeye Priacanthus arenatus, Stripped weakfish Cynoscion guatucupa, and Jamaica weakfish C. jamaicensis. The specimens were collected from fishing landings off the Rio de Janeiro, SW Atlantic. Additionally, we calculate the estimated weekly intakes (EWI) and the maximum amount of fish (MAF) that can be safely ingested, both based on the provisional tolerable weekly intake (PTWI). The highest THg concentrations were recorded in P. brasiliensis with a mean of 340.59 μg/kg (dry weight) and the lowest in P. arenatus (115.75 μg/kg). THg concentrations were positively related to the δ15N ratios indicating an increase in contamination with trophic level. All samples showed THg concentrations below the established limits by Brazilian and international regulation. Hg intake via human fish consumption does not exceed the PTWI. The EWI varied from 1.41% (P. arenatus size class I) to 11.52% (P. brasiliensis class II) of the PTWI, while the estimated EWI for "fish consumers" varied between 8.35 and 68.07% PTWI. The MAF estimated for an adult (70 kg) could safely consume between 1277.85 and 7075.50 g/week. This study is an important baseline for monitoring and future comparisons. Therefore, it is important to maintain monitoring of mercury levels in fish species in different marine regions, especially those species most consumed by humans. [ABSTRACT FROM AUTHOR]

The settling velocity and composition of large estuarine suspended aggregates (macro-aggregates) were investigated in the well-mixed, tropical estuary of Todos os Santos Bay (NE Brazil). These aggregates, reaching up to several decimeters in length, are uncommon in estuaries where flow shear promotes the disintegration of larger particles, and might expedite the transit of suspended particulate matter towards the bottom. Sets of sediment traps, sieves, and a still chamber were used to collect and measure aggregate's properties in 14 field campaigns between 2015 and 2017. The results showed that suspended particulate matter concentrations in the order of 4 mg l−1 are associated with vertical fluxes of 51.5 ± 7.0 g m−2 day−1, of which 23 % are combustible material. The measured aggregate's settling speed, ranging in size from 14 to 103 mm (longest axis), varied from 12 to 34 mm s−1. The particulate organic carbon content of the aggregates is lower than the SPM's, varying from 10 to 31 %, and increase towards the bottom. Diatoms, inorganic, and organic detritus are common particles carried by the aggregates, whose speedy fall velocities make them an efficient medium to remove suspended particles from the water column and potentially increase sedimentation rates. [ABSTRACT FROM AUTHOR]

Todos os Santos Bay (BTS) is one of eleven large estuaries along the semi-arid Brazilian northeast coast. It is a positive, well-mixed estuary undergoing progressive fresh water limitations due to natural climatic processes and direct human intervention to the fluvial hydrology. This study investigates the variability of the thermohaline field along three water years (2013–2015) that encompassed close-to-normal hydric conditions and the most severe regional drought in the historical record. Moored temperature and conductivity sensors, monthly CTD profiling along the bay axis, and historical records of meteorology and river discharges showed that the seasonal oscillations of the thermohaline field are 2- to 3-fold larger than higher, tidal frequency oscillations, and that BTS becomes a seasonally negative, hypersaline estuary during a drought. Also, a density plug and inverse estuarine circulation can arise with a delay of the rainy season. Negative ecological impacts have been associated with such hydrographic conditions. Long-term climatic trends and future climatic projections indicate that the BTS and its catchment area may undergo more frequent and acute droughts, suggesting that the bay may often become a seasonally negative estuary. [ABSTRACT FROM AUTHOR]

The dynamics of estuarine systems is sensitive to changes in its forcing conditions, including the morphology of its inlets. Coastline retraction, which may be induced by climate change, can result in modifications of estuarine inlet morphology. Through the use of a validated numerical model, we evaluate the effects of the opening of a new inlet on a tide-dominated estuary (Caravelas estuary, Brazil). During the last decades, shoreline retraction and the breach of an internal drainage channel led to the formation of a new inlet that became the main estuarine channel. The morphological changes of the estuary resulted in changes to its estuarine processes, including the general increase in the influence of the tide on the system and changes to its asymmetry. Internal channels that interconnect adjacent estuaries present great changes caused by the morphological alterations, not only in the magnitude of the processes but also in the resulting net transport direction. The increase in the water flow caused by the opening of the channel leads to an increase in the amount of water and materials carried toward the estuary. The changes presented here for the Caravelas estuarine system and the possible implications for the functioning of such systems demonstrate the importance of evaluating morphological aspects in relation to their use and management. [ABSTRACT FROM AUTHOR]

This study reports on the deepest records (~ 24 m depth) of coral bleaching in a naturally temperature-stable environment (> 26 °C with an intra-annual variability of ~ 2 °C), which was recorded during a mass bleaching event in the locally dominant, massive scleractinian coral Siderastrea stellata in equatorial waters of Brazil (SW Atlantic). An inter-annual analysis (2002–2017) indicated that this bleaching event was related to anomalies in sea surface temperature (SST) that led to the warmest year (2010) in this century (1 to 1.7 °C above average). Such anomalies caused heat stress (28.5–29.5 °C) in this equatorial environment that resulted in a bleaching event. Our results suggest that the increase in SST, low turbidity, and weak winds may have acted together to affect these stress-tolerant corals in marginal reefs. The equatorial coastline of Brazil is characterized by low intra-annual and inter-annual variations in SST, which suggests that the S. stellata corals here may be acclimatized to these stable conditions and, consequently, have a lower bleaching threshold because of lower historical heat stress. [ABSTRACT FROM AUTHOR]

The propagule pressure exerts an important role during the bioinvasion process. However, this biological characteristic of invasive species is still poorly understood for marine invertebrates. Here, we investigated aspects of the propagule pressure of the cryptogenic calcareous sponge Heteropia cf. glomerosa in the northeastern coast of Brazil. The investigated population was continuously reproductively active. Oocytes were present mainly during the rainy season, while embryos and larvae only during the dry season. The reproductive effort of this species was among the highest observed for sponges. The wet weight of the species did not influence on the reproductive output, but the number of tubes with apical osculum comprising the sponge was related to the number of oocytes. The reproduction of H. cf. glomerosa seemed to be driven by temperature, tides, and photoperiod. Our findings indicate that this species presents an opportunistic life history strategy enabling it to reproduce early in its life cycle with abundant propagules. As photoperiod is one of the drivers of its reproduction, it is expected that in higher latitudes (where this species has been found), the reproductive effort may exert an even higher pressure for the establishment and dispersion of the species. If H. cf. glomerosa is confirmed as a non-native in the study area, our results indicate that the best time to apply field efforts to avoid the expansion and establishment of the species is during the rainy period, when fewer larvae are found. [ABSTRACT FROM AUTHOR]

A very high-resolution modelling configuration was created for the estuary of Baía de Todos os Santos – BTS, Brazil (300 to 400 m), and adjacent coastal waters (600 to 1200 m). The adoption of a multi-corner domain approach allowed the variable spatial resolution required to resolve the shelf, the bay and their interactions. Seven years were simulated using realistic oceanic, atmospheric and riverine forcing. Model validation was done against observations showing the model skill to reproduce the thermohaline field, the tidal currents, as well as the variability of the free surface at tidal and sub-tidal time scales. The results provide the first representation of the tidal wave propagation along the bay, in terms of maps of amplitudes, phases and ellipses of the barotropic currents for the main tidal constituents. By analysing the residual currents at different depths, in terms of averages over the simulation period, several prominent structures were identified and named: (i) Salvador eddy (up to 0.2 m s−1); (ii) St Antonio current (up to 0.45 m s−1); (iii) Salvador current (up to 0.5 m s−1); (iv) Itaparica eddy (up to 0.2 m s−1); (v) Ilha dos Frades southern eddy (up to 0.1 m s−1); and (vi) Ilha dos Frades northern eddy (up to 0.2 m s−1). The model set-up proved to be highly efficient and robust simulating the BTS shelf-estuary region and such an approach may be suitable to other estuarine systems. [ABSTRACT FROM AUTHOR]

The size at which sexual maturity is reached is a key population parameter used to guide the setting of minimum legal size limits in fisheries. Understanding spatial and temporal variations in size at maturity is fundamental to management because the relationship between size at maturity and minimum legal size limits affects the fraction of the mature population biomass that is harvested, and resulting egg production, larval settlement and recruitment. This study measured the size at maturity of female Southern Rock Lobster (Jasus edwardsii) across South Australia between 1991 and 2015 in relation to known oceanographic characteristics, surface and subsurface temperature data, and relative changes in lobster abundance. There was pronounced north to south spatial variation in estimates of size at maturity. Larger average size at maturity was recorded in warmer north-western areas of the fishery relative to the cooler waters of the south-east. Estimates of size at maturity also differed over 25 years across the fishery. However, the nature of temporal responses varied spatially, and were more consistent with variations in surface and subsurface water temperature at local-scales than changes in lobster density. In the well-mixed waters of the north-western, western and south-eastern parts of the fishery, relatively high rates of increase in sea-surface temperature and size at maturity were recorded since 1991, indicating that size at maturity may be responding to ocean warming associated with global climate change. In more central parts of the fishery, contrasting temporal signals in sea-surface temperature (positive) and bottom temperature (negative) indicated increases in upwelling strength over the study period, and formation of a bottom cold pool below a warm surface layer, with corresponding decreases in size at maturity recorded. The spatio-temporal changes in size at maturity measured in this study highlight the need for oceanographic information to be integrated into future stock assessment models to enhance harvest strategy development, allow timely adaptive management decisions and increase the resilience of fisheries to the impacts of climate change. [ABSTRACT FROM AUTHOR]

We use the exact analytical solution of the radial part of the Klein–Gordon equation describing a charged massive scalar field in the electrically charged Garfinkle–Horowitz–Strominger dilaton black hole spacetime, given in terms of the confluent Heun functions, to study the physical phenomena related to resonant frequencies associated with this field, and also to examine some aspects related to its Hawking radiation. The special case of a Schwarzschild spacetime is also considered. [ABSTRACT FROM AUTHOR]

Turbidity increase is one of the main stressors to coral reefs. It affects light availability and will act together with global sea level rise to reduce potential photosynthesis that is important to light-enhanced calcification in corals. Corals are the main contributors to the morphological complexity of reefs through skeletal calcification. Bioconstruction by corals is a multifactorial process that is controlled by physical (e.g., irradiance and turbidity) and biological factors such as photoacclimation process. In this paper, we intend to show how turbidity and photobiology might interplay to produce a coral species distribution that controls reef growth and structural complexity. The Abrolhos complex is composed by a group of reefs closer to the coastline characterized by a high light attenuation value (Kd490 = 0.11), and another one about 60 km far from the coast characterized by a light attenuation coefficient of Kd490 = 0.08. In these reefs, different coral communities produce bioconstruction potential accordingly. We used data collected for 7 yrs, with the AGRRA (Atlantic and Gulf rapid reef assessment) Protocol. Coral species cover and distribution data were used to estimate reef bioconstruction [sensu Done (1995)] rates. A field experiment examined the metabolic function of five species (Mussismilia braziliensis, Mussismilia hispida, Mussismilia harttii, Montastraea cavernosa and Siderastrea stellata) through respirometry and rapid light curves (RLC). Bioconstruction potential and primary gross productivity demonstrated a substantial variability between reefs and species. In combination, these functional responses meant that coral species distribution is controlled by local factors and acclimation process. Therefore, our results suggest that these functional responses are useful tools to understand photoacclimation process and its consequences, species distribution and the space occupation on Abrolhos bank. We highlight the deleterious effect of turbidity in bioconstruction. This suggests that the local processes that increase sediment runoff is an immediate impact and must be controlled. [ABSTRACT FROM AUTHOR]