Mangrove species may differ in foliar elemental composition, but the extent to which these differences are maintained across contrasting local contexts remains unclear. We investigated how species identity and site jointly structure the foliar elemental composition of three mangrove species (Rhizophora mangle, Laguncularia racemosa, and Avicennia schaueriana) across two contrasting sites in Todos os Santos Bay, northeastern Brazil. Foliar concentrations of ten elements were analyzed using principal component analysis, PERMANOVA, and permutation-based univariate tests with false discovery rate correction. Species identity was the main source of multivariate variation, explaining 21.6% of the variation in foliar elemental composition, while site explained 5.2%. All three species differed significantly in their multivariate elemental profiles. Species-associated differences involved Mn, Sr, Zn, Na, Ca, K, Mg, and P, whereas site-associated differences were restricted to Mn and Ca. No significant species × site interaction was detected, indicating that species differences were not detectably modified between the two sites examined. These results show that foliar elemental composition reflects both species identity and local context, with species identity providing the stronger component of variation within the spatial scope of this study. Accounting for species identity is therefore essential when interpreting spatial patterns in mangrove foliar elemental composition.

Historical PAHs contamination is well documented in urbanized estuaries; however, their dynamics in tropical ecosystems considered relatively preserved remain poorly investigated. This study reconstructs the historical deposition of PAHs in the Serinhaém Estuary, a tropical Environmental Protection Area in Northeastern Brazil, quantifying their concentrations, distinguishing their sources, and assessing the associated ecological risks. To achieve these objectives, five sediment cores were collected, dated using 210Pb geochronology, and analyzed by gas chromatography. Diagnostic ratios and multivariate statistical analyses were applied to identify contaminant sources and distribution patterns. The sedimentation rate was approximately 2.5 ± 0.1 mm·year-1. Results showed that cores C1 to C4 were dominated by high-molecular weight PAHs of predominantly pyrogenic origin, likely associated with regional biomass burning. In contrast, core C5, located downstream, displayed low concentrations with petrogenic signatures, suggesting inputs related to maritime activities. Core C3 exhibited the highest total concentration (Σ16PAHs = 1508 ng·g-1), with a pronounced peak in the early 2000s. In this layer, compounds such as fluoranthene (154.36 ng.g-1), benzo[a]anthracene (138.55 ng.g-1), chrysene (138.91 ng.g-1), benzo[a]pyrene (153.86 ng.g-1), and dibenzo[a,h]anthracene (42.64 ng.g-1) exceeded threshold effect levels (TEL), indicating potential ecological risk. Multivariate analyses confirmed both vertical and lateral heterogeneity, highlighting specific episodes of increased contaminant input. Although overall concentrations ranged from low to moderate, distinct contamination events were identified, reflecting contributions from both diffuse and localized sources. These findings demonstrate that even legally protected estuaries remain vulnerable to anthropogenic pressures. Reconstructing sedimentary records proves essential for understanding the history of contamination and underscores the need for continuous monitoring to support effective conservation strategies.

This study assessed the environmental quality of the Serinhaém River estuary (Bahia, Brazil). The characterization was based on concentrations of chemical elements, total organic carbon (TOC), physicochemical parameters, and polycyclic aromatic hydrocarbons (PAHs) in surface sediments, combined with benthic foraminifera as bioindicators. Samples were collected at multiple sites during two seasonal campaigns conducted in 2013 and 2022, representing pre- and post-spill conditions. Chemical element concentrations showed no significant temporal differences but high spatial variability, with Fe, Al, and Mn predominating, indicating association with oxyhydroxides and aluminosilicates. PAHs in 2022 indicated low-to-moderate contamination, predominantly of pyrogenic origin, and did not exceed threshold effect levels (TEL and PEL). In 2013, benthic foraminiferal distribution was mainly influenced by precipitation, promoting transport toward the estuary mouth. In 2022, salinity and pH became the dominant controlling factors. Significant associations were observed between PAHs and benthic foraminiferal assemblages. Negative associations were observed between naphthalene and anthracene and the diversity and abundance of tolerant species (e.g., Ammonia beccarii and Textularia gramen), while dibenzo[a,h]anthracene showed a positive association with Ammoglobigerina globigeriniformis. Overall, the estuary remains preserved regarding elemental concentrations; however, PAHs influence benthic assemblages, highlighting foraminifera as effective indicators of environmental quality and hydrocarbon contamination.

A expansão urbana sem planejamento tem afetado a qualidade dos corpos d’água, em diversas regiões do Brasil, especialmente em Feira de Santana (BA), que é uma cidade historicamente conhecida pelo elevado número de lagoas em seu território. Neste estudo realizamos uma avaliação da qualidade ambiental de duas lagoas urbanas, que foram artificialmente separadas para a construção de uma avenida, em Feira de Santana/BA usando um Protocolo de Avaliação Rápida (PAR), parâmetros físico-químicos e concentrações de metais na água. Os resultados demonstram que a separação artificial do corpo hídrico resultou em duas lagoas com características físico-químicas distintas. A lagoa do Prato Raso, que conta com ocupação desordenada nas margens e constante descarte de resíduos sólidos e esgoto apresentou índices mais negativos, sendo classificada no PAR como impactada, e apresentando índices alterados para quase todos os parâmetros físico-químicos em relação às águas de classe 2, e alguns parâmetros em relação às águas de classe 3, enquanto a Lagoa do Geladinho, que está inserida em uma área de parque recreativo, foi considerada como alterada na avaliação do PAR, mas manteve-se dentro dos limites estabelecidos para águas de classe 2 para os parâmetros analisados, exceto a DBO. Em relação aos metais, as concentrações de Fe, Zn, Cr e Mn estão acima dos valores estabelecidos pelo CONAMA para águas de classe 2 em ambas as lagoas. A Lagoa do Geladinho apresentou valores elevados de coliformes termotolerantes enquanto estes não foram detectados na lagoa do Prato Raso. Estes resultados demonstram que lagoas separadas artificialmente podem sofrer impactos de maneiras distintas e que o monitoramento e estratégias de mitigação de impactos nas duas lagoas são necessários.

A granulometria dos materiais influencia suas propriedades espectrais, afetando a interação da luz com o material. Partículas menores dispersam mais luz, aumentam a refletância em certos comprimentos de onda, enquanto partículas maiores diminuem a reflectância. Este estudo avaliou como diferentes granulometrias impactam a análise espectral de sedimentos. O experimento foi realizado a partir do sedimento coletado no manguezal de Baixa Fria, Bahia, uma área com altos impactos ambientais. As amostras de sedimentos foram coletadas e submetidas a três tratamentos: destorroamento com almofariz e pistilo (T1), peneiramento em malha de 10 MESH (2,00 mm, T2) e em malha de 230 MESH (0,063 mm, T3). As amostras foram analisadas com Espectrorradiômetro que abrange comprimentos de onda de 350 a 2500 nm, e seus dados tratados estatisticamente para entender as correlações entre granulometria e propriedades espectrais e comparar as curvas espectrais com bibliotecas de minerais puros do Serviço Geológico dos Estados Unidos (USGS). Os resultados indicaram que a granulometria afeta significativamente a reflectância dos sedimentos, com partículas menores (0,063 mm) apresentando maior reflectância (51%) e partículas maiores (2,0 mm) a menor reflectância (36%). Além disso, as análises espectrais identificaram feições de absorção da montmorilonita, evidenciando uma composição química semelhante das amostras. Assim, este estudo destaca a importância da granulometria na interpretação dos dados espectrais, promovendo um entendimento das interações entre luz e partículas de sedimentos.

Os manguezais se localizam em boa parte do Litoral Brasileiro, tendo como destaque a Baia de Todos os Santos (BTS) como a segunda maior baía navegável do Brasil (HATJE & ANDRADE, 2009) e uma das maiores do mundo (SARAIVA, 2008).

O manguezal oferta serviços ecossistêmicos basilares para a reprodução material e simbólica da vida social e da biodiversidade nas áreas costeiras na América Latina e no mundo. O objetivo deste estudo foi investigar os indicadores ecológicos-geobotânicos (biometria e integridade foliar) e os níveis de metais-traços (Cu, Zn, Cd e Pb) nos sedimentos e nas folhas de Avicennia schaueriana na APA Área de Proteção Ambiental Tinharé-Boipeba, Cairu, no Litoral Sul da Bahia, com ênfase na conservação ambiental. Foram coletadas folhas da Avicennia em nove pontos amostrais para análises ecológico-geobotânicas e de metais-traço (FAAS). Os níveis foliares dos metais foram considerados normais e não tóxicos, sendo inferiores às áreas costeiras impactadas pelas atividades e usos da terra urbano-industrial. Além disso, os níveis dos metais-traços nos sedimentos dos bosques de mangue da APA não podem ser considerados poluídos. Os valores do fator de concentração (FC < 1) indicaram que os metais não estariam biodisponíveis e que o acúmulo destes nas folhas não correspondeu aos níveis nos sedimentos. A abordagem multivariada permitiu que fossem identificados um subgrupo de metais-traço de menor mobilidade geoquímica (Pb, Cu) e outro de maior mobilidade geoquímica (Cd, Zn). Desvelou, também, que as alterações nas variáveis geobotânicas podem decorrer da distribuição dos níveis de Zn, da herbivoria, ou ainda de estressores não investigados nesta pesquisa, como a influência das marés, salinidade, precipitações e aporte de água doce. Destaca-se a relevância de estudos ecológicos-geobotânicos e de biogeoquímica para a conservação da natureza e para a gestão territorial sustentável dos ecossistemas costeiros da APA Tinharé-Boipeba, Cairu.

The harmful effects of chemical contamination of the environment have motivated the search for tools for the assessment of environmental quality, including bioindicators. Here we evaluate the bioaccumulative potential of benthic and nektonic tadpoles occurring in areas affected by iron ore tailings. We analyzed the concentrations of Al, Ba, Cd, Cr, Cu, 34 Fe, Mn, Ni, Pb, Ti, V and Zn in the water, sediment, and in benthic tadpoles with intestine (BI) and surgically removed intestine (BR), and nektonic tadpoles with intestine (NI) and 36 removed intestine (NR). We collected tadpoles in seven sites directly affected by the tailings and in seven sites without direct contact with the tailings mud. There were no differences in concentrations of heavy metals between the sampling points for water and sediment. Benthic tadpoles (BI) from sites directly affected by the tailings showed higher concentrations of metals Al, Ba, Fe, Mn and Ti, than nektonic tadpoles (NI). On the other hand, NR showed higher concentrations of Cr, Al, Ni, Mn, Zn, Cu and Ti than BR. The highest concentration of metals BI may be linked to the association of the group with the metals adsorbed to the sediment, where there were the highest concentrations. The metals associated with NR are due to accumulation in different tissues of the body. In general, the concentrations of metals in the environment are reflected in the tadpoles’ tissues. Additionally, the differences between benthic and nektonic tadpoles show the movement of these metals along the trophic chain in this ecosystem.

Species distribution modeling (SDM) is a vital tool for ecological and biogeographical research, allowing precise predictions of species distributions based on environmental variables. This study reviews the evolution of SDM techniques from 1985 to 2023, focusing on model development and applications in conservation, climate change adaptation, and invasive species management. We employed a mixed review with bibliometric and systematic element approaches using the Scopus database, analyzing 982 documents from 275 sources. The MaxEnt model emerged as the most frequently used technique, applied in 85% of the studies due to its adaptability and accuracy. Our findings highlight the increasing trend in international collaboration, particularly between China, the United Kingdom, and Brazil. The study reveals a significant annual growth rate of 11.99%, driven by technological advancements and the urgency to address biodiversity loss. Our analysis also shows that while MaxEnt remains dominant, deep learning and other advanced computational techniques are gaining traction, reflecting a shift toward integrating AI in ecological modeling. The results emphasize the importance of global cooperation and the continued evolution of SDM methodologies, projecting further integration of real-time data sources like UAVs and satellite imagery to enhance model precision and applicability in future conservation efforts.

The Doce River Basin (DRB) suffers with the adverse impacts of mining activities, due to its high level of urbanization and numerous industrial operations. In this study, we present novel insights into contaminant flow dynamics, seasonal variations, and the primary factors driving concentration levels within the region. We conducted an extensive analysis using a database sourced from the literature, which contained data on the contamination of arsenic (As) and lead (Pb) in the Doce River. Our primary aim was to investigate the patterns of As and Pb flow throughout the entire basin, their response to seasonal fluctuations, and the key parameters influencing their concentration levels. The results showed significant seasonal fluctuations in As and Pb fluxes, peaking during the rainy season. The 2015 Fundão dam breach in the DRB led to notable changes, elevating elemental concentrations, particularly As and Pb, which were subsequently transported to the Atlantic Ocean. These increased concentrations were primarily associated with iron and manganese oxides, hydroxides, and sulfates, rather than precipitation, as evidenced by regressions with low R2 values for both As (R2 = 0.07) and Pb (R2 < 0.001), concerning precipitation. The PCA analysis further supports the connection between these elements and the oxides and hydroxides of Fe and Mn. The approach employed in this study has proven to be highly effective in comprehending biogeochemical phenomena by leveraging data from the literature and could be a model for optimizing resources by capitalizing on existing information to provide valuable insights for drainage basin management, particularly during crises.

Heavy metal determination in surface sediment allows pollutant assessment when the detection in the water column is not possible. Geoaccumulation Index (Igeo) and the Sediment Quality Guidelines (SQGs) were used to quantitatively evaluate the degree of heavy metal contamination in fluvial sediments. Both of these methods had already been used by several authors and the generated indexes allowed a good comparison parameter. In the present study, heavy metal in sediments (Mn, Zn, Cd, Cr, Cu, Pb and Ni) were analyzed in 14 sampling points, distributed in the upper watercourse of Subaé river, Feira de Santana – BA, in two field campaigns in order to compare dry and wet seasons. The quantification of heavy metal contents was measured by flame atomic absorption spectrometer. The heavy metal levels in the sampling points were low when compared to the global reference values for world sediments. Cadmium concentrations were always below the detection limit of the used spectrometer, and the relative abundance of the studied metals was the following: Mn>Zn>Pb>Cu>Cr>Ni. The variation range of each element concentrations was: Mn 69.3 and 266 mg Kg-1; Zn 30.7 and 426 mg Kg-1; Pb 6.00 and 63.6 mg Kg-1; Cu 4.26 and 66.2 mg Kg-1; Cr 3.24 and 52.9 mg Kg-1; Ni 1.96 and 24.7 mg Kg-1. These results are indicating low contamination risk to biota, despite of the fact that some points presented moderate risk of toxicity. The Igeo ranged from unpolluted (Zn, Mn, Cr, and Ni) to slightly polluted (Pb and Cu) in the assessed sediments. The different approaches to geochemical information treatment allow a wide and coherent debate about the environmental risk of heavy metals from anthropogenic diffuse sources.

In 2019, the Brazilian coast was affected by the largest oil spill in its history. We assessed the levels of chemical elements in Lutjanus synagris and Haemulon aurolienatum fish from Itacaré (least affected area), Tinharé-Boipeba (most affected area) and Madre de Deus (chronically affected area). The level of metals differed between species, tissues, life cycle phases, maturation stages and between sampled locations, indicating the influence of biological and environmental aspects on bioaccumulation. Only fish in Madre de Deus showed lead contamination, while arsenic concentrations in the three areas exceeded the maximum value acceptable by Anvisa (National Health Surveillance Agency). It is suggested that the oil spill may have impacted species differently, also having an impact in fish from less affected areas. However, metal concentrations in fish in Madre de Deus stood out when compared to populations in other studied areas.

The activities of microbiomes in river sediments play an important role in sustaining ecosystem functions by driving many biogeochemical cycles. However, river ecosystems are frequently affected by anthropogenic activities, which may lead to microbial biodiversity loss and/or changes in ecosystem functions and related services. While parts of the Atlantic Forest biome stretching along much of the eastern coast of South America are protected by governmental conservation efforts, an estimated 89% of these areas in Brazil are under threat. This adds urgency to the characterization of prokaryotic communities in this vast and highly diverse biome. Here, we present prokaryotic sediment communities in the tropical Juliana River system at three sites, an upstream site near the river source in the mountains (Source) to a site in the middle reaches (Valley) and an estuarine site near the urban center of Ituberá (Mangrove). The diversity and composition of the communities were compared at these sites, along with environmental conditions, the former by using qualitative and quantitative analyses of 16S rRNA gene amplicons. While the communities included distinct populations at each site, a suite of core taxa accounted for the majority of the populations at all sites. Prokaryote diversity was highest in the sediments of the Mangrove site and lowest at the Valley site. The highest number of genera exclusive to a given site was found at the Source site, followed by the Mangrove site, which contained some archaeal genera not present at the freshwater sites. Copper (Cu) concentrations were related to differences in communities among sites, but none of the other environmental factors we determined was found to have a significant influence. This may be partly due to an urban imprint on the Mangrove site by providing organic carbon and nutrients via domestic effluents.

O crescimento econômico e populacional que ocorreu/ocorre na cidade de Feira de Santana na Bahia, ocasionou um crescimento desordenado na cidade e comprometeu seus ambientes naturais, dentre eles as lagoas urbanas. Em vista disso, esse estudo tem como objetivo avaliar a concentração e o comportamento dos metais (Fe, Ni, Cd, Zn, Cr, Cu, Mn, Pb), em sedimentos, ao longo do tempo, em duas lagoas urbanas da referida cidade, e assim oferecer dados que expliquem as contribuições superficiais. Para alcançar a proposta desse trabalho, foram coletados cinco testemunhos de sedimentos, sendo 3 na Lagoa Salgada e 2 na Lagoa Subaé. Os resultados geoquímicos obtidos nos corpos aquáticos demonstraram que eles apresentam indícios de contaminação por chumbo nas duas lagoas e por cromo na lagoa Subaé, porém não representam grau de contaminação, sendo sugerido, portanto, um olhar cuidadoso para evitar futuros problemas nesses ambientes. Palavras-chave: testemunho de sedimentos, metais pesados, lagoas urbanas.

The city of Santo Amaro (Bahia, Brazil) gained visibility among the scientific community due to the contamination of the Subaé River by lead and cadmium from the PLUMBUM Mineração e Metalurgia Ltda industry, on the banks of the river in 1956, which produced lead ingots The present work aimed to investigate the adsorption capacity of heavy metals (Pb and Cd) of EPS produced by bacterial species from the Subaé River, for possible future application of these biopolymers in bioremediation processes in areas impacted by the aforementioned heavy metals. Subaé river water was collected for physical-chemical analysis and bacterial isolation. It was verified that all isolated bacteria produced an expressive amount of Exopolysaccharide (EPS). Thus, the optimization of this production in different sugars (sucrose, glucose, and mannitol) and in three different pHs: 5.5; 6.5, and 7.5. All bacteria produced EPS in large quantities and the best sugar was sucrose at pH 7.5. In order to use the EPS for the bioremediation area, the adsorption test of lead and cadmium was carried out by the isolated EPS. 0.5 g of the EPS was dissolved in 50 ml of deionized water, then the solutions of metals, lead acetate, and cadmium sulfate (procedure performed separately) were incubated at 28 °C for 16 h after that period, and were centrifuged. Samples were filtered to separate the insoluble EPS and the filtrates obtained were used in the quantification of the metals by atomic absorption (FAAS- Flame Atomic Absorption Spectrometry). Bacillus spp., Bacillus cereus, Staphylococcus spp., and Serratiamarcescens, all showed tolerance to the tested metals, due to the efficiency in the adsorption capacity of the EPS, and it was possible to distinguish seven genera, Klebsiella pneumonia, Pseudomonas aeruginosa, Lysinibacillus spp. to be used in the bioremediation of environments contaminated with heavy metals.

A qualidade da água dos recursos hídricos é diretamente influenciada pela vegetação presente em suas margens e pelas ações humanas uma vez que os corpos de água possuem capacidade de assimilar poluentes e se auto depurar (Simedo et al., 2015).

The purpose of this study is to determine the concentrations of total mercury in muscle of Hoplias malabaricus collected in lakes of the North Fluminense and bought in the Municipal Market (MM) since these lakes have suffered from the use of mercury fungicides in sugar cane plantations. The concentrations of mercury were measured by equipment ICP/AES with enhancement of cold vapor. The concentrations of Hg in the lake Campelo (525.6 μg kg-1) exceeded the concentrations of other lakes and fish of MM. An inverse correlation was observed between the concentrations of Hg and the standard length, weight and age in samples of fish from the Taquaruçu and Campelo lakes. Direct correlation between the concentrations of Hg and biological variables were observed for Feia lake, Cima lake and samples of MM.

This review examines the pivotal interaction between the energy transition and the bioeconomy, underscoring their pivotal role in mitigating climate change, resource limitations, and socioeconomic disparities. The study aims to map the evolution of ETBE research, identifying key themes, regions, and scholarly contributions driving progress in these fields. Using a bibliometric and systematic elements review approach, the study analyzes trends, collaborations, and thematic clusters from 2000 to 2023. The findings reveal exponential growth in ETBE research, with distinct thematic focuses on policy, technology, socio-economic impacts, and sustainability. Four major thematic clusters are identified: policy and economy, societal and environmental implications of energy transitions, energy systems and technologies, market dynamics, and strategic planning. The analysis underscores the global collaboration between leading nations like the United States, China, and Germany, which play pivotal roles in advancing ETBE research and innovation. While energy transition dominates the discourse, the integration with bioeconomy still needs to be explored, accounting for only 14% of the reviewed studies. This highlights the need for greater synergy between renewable energy technologies and bio-based solutions to achieve holistic sustainability goals. The review concludes that fostering inclusive collaborations, prioritizing equity, and aligning renewable energy with bioeconomic strategies are essential for achieving a low-carbon, sustainable future. The study provides a roadmap for future research and policy, emphasizing the critical importance of interdisciplinary and international efforts in shaping the global energy transition and bioeconomy landscape.

The village of Colonia, in the municipality of Itaeté, is one of the first agrarian reform settlements in Bahia, northeastern Brazil. It corresponds to the ancient locality of Pirainha, located on the banks of the Rio Una, one of the main contributors to the Paraguaçu Rio in the Chapada Diamantina, in the Caatinga domain. Today the community has just over 1600 inhabitants. Until 1998 the Rio Una was a perennial river. The river beach has always been a place of leisure for riverside residents. But by the end of 1998 the Rio Una was mostly dry, and since then it has been cut in the dry season. Through environmental experiences and practices, a video was prepared and edited – which aims to bring to public knowledge the communicative and affective attitudes, towards the revitalization of the river that is the source of life of the community.