Resumen:La demanda creciente del sector vivienda en la ciudad de Machala-Ecuador convirtió a las invasiones en el modelo común de crecimiento desorganizado de esta ciudad, donde utilizan el estero “El Macho” para la eliminación de desechos y aguas negras. Estudios preliminares respecto al contenido de metales pesados en este estero concluyen que las concentraciones de metales como el cadmio son superiores a los límites establecidos en la normativa del Texto Unificado de Legislación Secundaria del Ministerio del Ambiente. En la presente investigación se evaluó la remoción de cadmio de muestras de aguas del estero “El Macho” utilizando espuma de poliuretano activada con nanopartículas de plata como adsorbente. Para la recolección de los datos de adsorción se diseñó de un reactor tubular vertical, utilizando 1,560 g de adsorbente de poliuretano modificado con nanopartículas de plata, pH 8 y tamaño de la espuma de poliuretano de forma cubica de 0,5 cm de lado. Se cuantificó las concentraciones de cadmio mediante espectroscopia de absorción atómica, en muestras de aguas del Estero antes y después de su paso por el reactor. Se concluye que la espuma de poliuretano activada con nanopartículas de plata, como adsorbente, alcanzó un porcentaje de remoción de 48,75% y, por lo tanto, es efectivo para el tratamiento de aguas contaminadas con cadmio.

Abstract:The growing demand of the housing sector in the city of Machala-Ecuador turned invasions into the common model of disorganized growth of this city, where they use the “El Macho” estuary for the disposal of waste and sewage. Preliminary studies regarding the content of heavy metals in this estuary conclude that the concentrations of metals such as cadmium are higher than the limits established in the regulations of the Unified Text of Secondary Legislation of the Ministry of the Environment. In the present investigation, the removal of cadmium from water samples of the “El Macho” estuary was evaluated using polyurethane foam activated with silver nanoparticles as an adsorbent. To collect adsorption data, a vertical tubular reactor was designed, using 1,560 g of polyurethane adsorbent modified with silver nanoparticles, pH 8 and cubic-shaped polyurethane foam size of 0.5 cm of side. Cadmium concentrations were quantified by atomic absorption spectroscopy in samples of Estero water before and after passing through the reactor. It is concluded that the polyurethane foam activated with silver nanoparticles, as an adsorbent, reached a removal percentage of 48.75% and therefore, it is effective for the treatment of water contaminated with cadmium.

Abstract Background: Mangroves are communities whose structure expresses patterns according to the coastal landforms in which they develop. Questions: Is there a structural variation of mangroves among landforms and regions of the South Pacific? What is the effect of the geomorphological-regional factor on the structure of mangroves? What is the level of consistency of mangrove structure within each analyzed landform and region? Data description: Basal area, height, density, complexity index, and importance value. Study site: Mangroves from 39 systems in five hydrological regions in the states of Guerrero, Oaxaca, and Chiapas, Mexico. Methods: The structural classification of mangroves was carried out considering the landform (inlet, estuary, lagoon) and the hydrological region. Correlations were used to assess their relationship with salinity and water recharge, and multivariate techniques were employed to identify differences between factors and clustering patterns. Results: Density and basal area correlated positively with water recharge, and it was found that mangrove density and complexity varied significantly among landforms and regions, while basal area and height were affected by landform and region. Discrete groups of variables in ordinations were not evident, with greater structural variability of mangroves found by hydrological region rather than landform. Conclusions: There is structural variation in mangroves among landforms and regions of the South Pacific; however, the variation in basal area, height, and density is low, resulting in consistency when compared across hydrological regions.

Resumen Antecedentes: Los manglares son comunidades cuya estructura expresa patrones de acuerdo a las geoformas costeras en las que se desarrollan. Preguntas: ¿Existe una variación estructural de los manglares entre geoformas y regiones del Pacífico sur? ¿Cuál es el efecto del factor geomórfico-regional sobre la estructura de los manglares? ¿Cuál es el nivel de consistencia de la estructura de los manglares entre cada geoforma y región analizada? Descripción de datos: Área basal, altura, densidad, índice de complejidad y valor de importancia. Sitio de estudio: Manglares de 39 sistemas de cinco regiones hidrológicas en los estados de Guerrero, Oaxaca y Chiapas, México. Métodos: La clasificación estructural de los manglares se realizó considerando la geoforma (bocana, estero, estuario, laguna) y la región hidrológica. Se emplearon correlaciones para evaluar su relación con la salinidad y la recarga hídrica; y técnicas multivariadas para identificar diferencias entre los factores y patrones de agrupación. Resultados: La densidad y el área basal se correlacionaron positivamente con la recarga hídrica, y se encontró que la densidad y la complejidad del manglar variaron significativamente entre geoformas y regiones; mientras que el área basal y la altura fueron afectadas por geoforma y región. Los grupos discretos de las variables en las ordenaciones no resultó evidente, encontrándose mayor variabilidad estructural de los manglares por región hidrológica que por geoforma. Conclusiones: Existe variación estructural en los manglares entre geoformas y regiones del Pacífico sur, sin embargo, la variación del área basal, altura y densidad es baja, resultando consistente al compararse entre regiones hidrológicas.

Verlorenvlei is a globally important RAMSAR wetland on the arid west coast of South Africa. A prolonged drought between 2016 and 2021 and increasing competition for water from the agricultural sector resulted in extremely low water levels. We used historical aerial and satellite imagery from 1942 and rainfall and water level data for the past 50 years, to assess habitat changes within the estuarine functional zone of the Verlorenvlei Estuarine Lake. Prior to the drought, lake water levels and water surface area remained stable (1113 ± 27 ha (SE)). Since then, there has been a 64% decrease in open water area, exposing 193 ha of sandbanks, of which 190.9 ha were hyper-sulfidic pyrite-rich. The water in the lower lake was hypersaline (>100), and in the middle, it was acidic (pH<3). The low water level plus sediment and nutrient input from surrounding agriculture resulted in a localised increase in reeds. Additional pressures, such as fires, have reduced the above-ground biomass of reeds and sedges, potentially altering surface morphology and reducing stored carbon. Despite flooding and filling up in June 2023, the lake remained in an acidic state (3.9-4.3). Similar low-lake level, hypersaline and acidic conditions are predicted to become more common under future climate change scenarios where aridity and extreme weather events are anticipated. Inflow of fresh water into the estuary and control of farming practices are required to keep the Verlorenvlei in a functional state, with long-term monitoring necessary to assess the ecological condition in response to restoration actions. SIGNIFICANCE: We assessed the habitat changes in Verlorenvlei, an estuarine lake on the arid west coast of South Africa. Estuarine lakes are scarce, and an extended drought greatly reduced the water surface area, exposing hyper-sulfidic pyrite-rich soils, leading to lake acidification and a negative response from biota. Competition for water from agribusiness and the burning of reeds are added pressures. Subsequent heavy rains have been slow to buffer lake acidity, and the impacts thereof serve as a warning for the management of similar ecosystems and their ecological water requirements, especially under climate change where extreme weather conditions, increased aridity and competition for water are realities.

ABSTRACT Microplastics (MP) pose a major environmental problem for estuaries areas, as they are exposed to multiple sources of plastic waste. In this study, the spatiotemporal influence of environmental variables on the abundance, distribution and types of MP in surface waters of Tumaco Bay were assessed. The samples were collected in the rainy and dry seasons of 2020, in the inner and outer estuary, and were processed by density separation. MP abundance was higher in dry season (11.40 ± 2.60 ítems/m³) and in the inner estuary (8.42 ± 4.91 items/m³). Fibers were the most abundant type of MP (53.89 %). Salinity and TDS were significantly correlated with fibers, and precipitation with fragments, films and total MP. These results demonstrate high contamination (8.13 items/m³) and an increase in MP concentration in Bay. This could be related to the exposure of waste carried by the rivers. On the other hand, the higher abundance of MP in the dry season could be due to a decrease in dispersion for an entrance fewer of water to system and an increase in density of water, related to the increase in salinity, which favors the buoyancy of MP.

RESUMEN Los microplásticos (MP) suponen una gran problemática ambiental para las zonas estuarinas, al estar expuestas a múltiples fuentes de desechos plásticos. En este estudio, se evaluó la influencia espacio-temporal de variables ambientales sobre la abundancia, distribución y tipos de MP en la bahía de Tumaco. Las muestras se recolectaron en épocas de lluvia y seca de 2020, en el estuario interno y externo, y se procesaron mediante separación por densidad. La abundancia de MP fue mayor en época seca (11.40 ± 2.60 ítems/m³) y en el estuario interno (8.42 ± 4.91 ítems/m³). Las fibras fueron el tipo de MP más abundante (53.89 %). Se correlacionaron significativamente la salinidad y solidos totales disueltos (TDS) con fibras, y la precipitación con fragmentos, láminas y MP totales. Estos resultados demuestran alta contaminación (8.13 ítems/m³) y un aumento de la concentración de MP en la bahía. Esto podría estar relacionado con la exposición a los residuos transportados por los ríos. Por otra parte, la mayor abundancia de MP en la época seca podría deberse a una disminución en la dispersión por una menor entrada de agua al sistema, y al aumento de la densidad del agua, relacionado con el incremento en la salinidad, que favorece la flotabilidad de MP.

Resumen La gestión del agua implica cuestiones complejas relacionadas a la asignación justa y sostenibilidad. Aunque han surgido enfoques integrados incorporando diversos interesados, como el enfoque global dominante para el siglo XXI, es difícil evaluar la participación e integración de los mismos. Este estudio generó datos primarios, a partir de cuestionarios y entrevistas, y realizó análisis de redes sociales para revelar y mapear la dinámica de interacción entre diez grupos interesados en los recursos hídricos en un parque estatal en Brasil. Los resultados indican que la interacción entre los grupos se concentró en dos conglomerados distintos, siendo que la alta interacción se correlacionó con el poder político, mientras que los más dependientes de los recursos se caracterizaron por una influencia limitada en decisiones y una baja interacción con otros grupos. Estos resultados proporcionan información sobre la gobernanza equitativa y sostenible de recursos hídricos y la evaluación de la participación e interacción entre grupos de interesados. sostenibilidad XXI mismos primarios entrevistas Brasil distintos político

Abstract The management of water involves complex issues related to just allocation and sustainability. While integrated approaches incorporating diverse stakeholders have emerged as the dominant global framework for 21st-century challenges, policymakers face difficulties in assessing stakeholder participation and integration. This study generated primary data from a survey and interviews and used social network analysis to reveal and map the dynamics of interaction among ten groups holding stakes in the water resources of the Açu Lake State Park, a Brazilian coastal estuary. The results indicate that stakeholder group interaction was concentrated within two distinct clusters, such that high interaction correlated positively with political power, while those most dependent on the resources were characterized by limited decision-making influence and low interaction with other groups. These results offer insight for the equitable and sustainable governance of water resources and the assessment of participation and interaction among stakeholder groups. sustainability 21stcentury stcentury 21st century st challenges integration Park estuary clusters power decisionmaking decision making

Resumo A gestão da água envolve questões complexas relacionadas à justa alocação e sustentabilidade. Embora abordagens integradas incorporando diversos interessados tenham surgido como a abordagem global dominante para os desafios do século 21, ainda se enfrenta dificuldades para avaliar a participação e integração de stakeholders. Este estudo gerou dados primários com questionário e entrevistas e usou a análise de redes sociais para revelar e mapear as dinâmicas de interação entre dez grupos interessados nos recursos hídricos de um parque estadual no Brasil. Os resultados indicam que a interação entre os grupos foi concentrada em dois aglomerados distintos, de modo que alta interação se correlacionou com poder político, enquanto aqueles mais dependentes dos recursos foram caracterizados por influência decisória limitada e baixa interação com outros grupos. Esses resultados oferecem insights para a governança equitativa e sustentável de recursos hídricos e a avaliação da participação e interação entre grupos de interessados. sustentabilidade 21 stakeholders Brasil distintos político 2

ABSTRACT Harmful algal blooms (HABs) can negatively affect coastal water quality, aquatic fauna, and human health from the consumption of toxin-contaminated seafood. Estuaries are especially prone to the incidence of these noxious events and sensitive to the associated damage. This study represents a comprehensive overview of previous investigations reporting the occurrence of harmful algae and/or phycotoxins in the Paranaguá Estuarine Complex (CEP), in Southern Brazil. Secondary data from 2002 to 2021 were combined with new results obtained from widely spaced sampling campaigns performed from 2018 to 2019 to assess the periods and estuarine sectors at greater risk for the incidence of HABs. In total, about 600 water/sediment samples containing harmful microalgae and 675 tissue samples of phycotoxin-contaminated fauna were analyzed. The most frequent and abundant species of potentially toxic microalgae were dinoflagellates belonging to the species complexes Dinophysis acuminata and Prorocentrum lima, producers of diarrhetic shellfish toxins (DSTs), and diatoms of the genus Pseudo-nitzschia, producers of amnesic shellfish toxins (ASTs). Okadaic acid, a DST, was by far the most common toxin in the fauna, reaching higher levels in primary consumers such as bivalve mollusks (mussels, oysters, and clams), zooplankton, and suspension-feeding crustaceans (ghost shrimps), and moderate to low levels in cephalopods, fishes, gastropods, echinoderms, sea turtles, seabirds, and cetaceans. Less rainy periods (winter-early spring) were associated with the highest incidence of DSTs and blooms of their producing algae P. lima and Dinophysis spp., mainly in the middle region of Paranaguá Bay and on the shallow continental platform adjacent to the estuarine mouth. However, certain HAB-forming species may be more successful in inner estuarine areas ( Prorocentrum cordatum) and during different periods, such as late summer—early fall ( Pseudo-nitzschia spp.). Continuous monitoring of harmful algae and toxins is therefore highly recommended to mitigate the effects of HABs in the entire estuary. (HABs quality toxincontaminated contaminated seafood damage andor or CEP, CEP , (CEP) Brazil 200 202 201 total 60 watersediment sediment 67 phycotoxincontaminated phycotoxin analyzed DSTs, (DSTs) Pseudonitzschia, Pseudonitzschia Pseudo nitzschia, nitzschia ASTs. ASTs . (ASTs) acid DST mussels, mussels (mussels oysters clams, clams clams) zooplankton suspensionfeeding suspension feeding ghost shrimps, shrimps shrimps) cephalopods fishes gastropods echinoderms turtles seabirds cetaceans winterearly winter early spring P spp spp. mouth However HABforming HAB forming cordatum summerearly summer spp.. spp.) estuary (CEP 20 6 (DSTs (ASTs 2

Resumo Contaminação por microplásticos (MPs) é um impacto bem estabelecido nos oceanos, embora sejam escassos enfoques combinando análises simultâneas dos componentes bióticos e abióticos. Este estudo foi direcionado para esta lacuna, demonstrando a ingestão de MPs por Atherinella brasiliensis (espécie de peixe) e comparando com a presença do contaminante na água e sedimento. Três praias de Ubatuba (exposta, calma e estuário abrigado) foram amostradas para os componentes peixe, água e sedimento durante o verão e o inverno. Dados ambientais evidenciaram diferenças espaciais e sazonais (ACP/ANOVA). A presença de partículas sintéticas (PSs) em peixes foi alta (~38%). Concentrações máximas ocorreram no estuário, para água (490 PSs/m³), e na praia exposta, para sedimento (62 PSs/50g). O formato fibra predominou em todos os componentes. Preferência dos peixes pela cor azul parece ocorrer. Relações estatísticas significativas foram determinadas para comprimento dos peixes e tamanho das PSs e entre concentrações de PSs na água e nos peixes. As identidades químicas (μ-FTIR spectra), polipropileno, polietileno, poliamida, poliéster e celulose/papelão predominaram. Influências da hidrodinâmica local (e.g., tamanhos das PSs) e da redução do turismo durante a epidemia de Covid-19 (e.g., menos PSs no verão) são discutidas. Este estudo confirma a contaminação por PSs (a maioria MPs) nas praias de Ubatuba, afetando os peixes através da ingestão direta na coluna d’água. Ações urgentes por parte das autoridades e mudanças de hábitos dos usuários locais são cruciais. (MPs oceanos abióticos lacuna espécie peixe exposta (exposta abrigado inverno ACP/ANOVA. ACPANOVA ACP/ANOVA . ACP ANOVA (ACP/ANOVA) (PSs ~38%. 38 ~38% (~38%) 490 (49 PSs/m³, PSsm³ PSsm PSs/m³ , m³ m PSs/m³) 62 (6 PSs/50g. PSs50g PSsg PSs/50g 50g g PSs/50g) ocorrer μFTIR μ FTIR spectra, spectra spectra) polipropileno polietileno poliamida celulosepapelão celulose papelão predominaram e.g., eg (e.g. Covid19 Covid 19 Covid-1 discutidas dágua. dágua d água. d’água cruciais (ACP/ANOVA 3 ~38 (~38% 49 (4 PSs/m 6 ( e.g. (e.g Covid1 1 Covid- ~3 (~38 4 e.g ~ (~3 (~

Abstract Microplastics (MPs) contamination is a well-established impact in oceans, but integrated approaches combining simultaneous analyzes of biotic and abiotic components are scarce. This study addresses this gap, demonstrating Atherinella brasiliensis (fish species) ingestion of MPs and comparing with the contaminant presence in water and sediment. Three Ubatuba beaches (exposed, calm and sheltered estuary) were surveyed for fish, water, and sediment components in summer and winter. Environmental data evidenced spatial and seasonal differences (PCA/ANOVA). Presence of synthetic particles (SPs) in fish was high (~38%). Maximum concentrations occurred in the estuary, for water (490 SPs/m³), and in the exposed beach, for sediment (62 SPs/50g). Fibers format predominated in all components. Fish preference for blue color seems to occur. Significant statistical relationships were determined for fish length and SPs size and between SPs concentrations in water and fish. The chemical identities (μ-FTIR spectra) polypropylene, polyethylene, polyamide, polyester, and cardboard/cellulose predominated. Influences of local hydrodynamics (e.g., SPs sizes) and reduction in tourism during Covid-19 epidemic (e.g.,less SPs in summer) are discussed. This study confirms environmental contamination by SPs (mostly MPs) in Ubatuba beaches, affecting fish through direct water column ingestion. Urgent actions from authorities and changes in local user’s habits are crucial. (MPs wellestablished well established oceans scarce gap species exposed, (exposed estuary winter PCA/ANOVA. PCAANOVA PCA/ANOVA . PCA ANOVA (PCA/ANOVA) (SPs ~38%. 38 ~38% (~38%) 490 (49 SPs/m³, SPsm³ SPsm SPs/m³ , m³ m SPs/m³) beach 62 (6 SPs/50g. SPs50g SPsg SPs/50g 50g g SPs/50g) occur μFTIR μ FTIR spectra polypropylene polyethylene polyamide polyester cardboardcellulose cardboard cellulose e.g., eg e (e.g. sizes Covid19 Covid 19 Covid-1 e.g.,less egless less discussed mostly users user s crucial (PCA/ANOVA 3 ~38 (~38% 49 (4 SPs/m 6 ( e.g. (e.g Covid1 1 Covid- ~3 (~38 4 e.g ~ (~3 (~

Marine pollution has become relevant for coastal conservation units and ecosystems of great ecological importance. This study validated analytical methods to investigate the occurrence of the emerging contaminants 17β-estradiol (E2), estrone (E1), estriol (E3), and 17α-ethinylestradiol (EE2) in surface waters and suspended particulate matter (SPM) from Guaratuba Bay, South Atlantic, Brazil. The analysis was performed by liquid chromatography coupled to a fluorescence detector (LC-FLD) after pre-concentration of surface water samples by solid phase extraction (SPE) or solid-liquid extraction for SPM samples. The recovery percentages were between 48 and 87%, and the coefficient of variation (CV) between 3 and 24% for SPM and from 64 to 107% (CV of 4 to 42%) for surface water. The method thus proved to be accurate and precise at the concentrations studied (ng g−1 and µg L−1). The concentration ranged from 10 to 177 ng L−1 in surface waters and from 392 to 4108 ng g−1 in SPM. E2, EE2, and E3 were found in SPM under different climatic conditions and population occupation. EE2 was determined in all sampling campaigns, especially in summer, when the number of tourists increases considerably. The presence of EE2 in the SPM of Guaratuba Bay warns for possible implications for the health of coastal environments. importance 17βestradiol βestradiol 17β estradiol β E2 E , (E2) E1, E1 (E1) E3, (E3) 17αethinylestradiol αethinylestradiol 17α ethinylestradiol α EE (EE2 (SPM Atlantic Brazil LCFLD LC FLD (LC-FLD preconcentration pre SPE (SPE solidliquid 87 87% CV 24 6 107 42% 42 g1 g 1 g− L−1. L1 L . L−1) 17 L− 39 410 occupation campaigns summer considerably environments (E2 (E1 (E3 (EE 8 2 41 (E

Abstract Centropomus undecimalis and Centropomus ensifurus are a species belonging to the family Centropomidae, which has an important role in estuarine ecosystem. The present study aimed at comparing the otoliths shape of juveniles both species collected in in the lower São Francisco River (10°28′34.02″S, 36°24′27.02″W). In the laboratory, 52 otoliths were extracted, photographed, measured and the contour was analyzed by the wavelet method. The otolith contours varied between species (n = 28 C. ensiferus and n = 24 C. undecimalis). The Linear Discriminant Analysis correctly reclassified 92.3% of all otoliths among species. MANOVA also evidenced significant differences in contour between species (F = 3.73; p < 0.0001). The results suggest that C. ensiferus is adapted to enviroments with higher turbidity and the C. undecimalis tends to colonize environments with lower turbidity and spends more time in the water column. Centropomidae ecosystem 10°28′34.02″S, 10283402S S 10 34 02 (10°28′34.02″S 36°24′27.02″W. 36242702W W 36°24′27.02″W . 36 27 36°24′27.02″W) laboratory 5 extracted photographed method 2 C undecimalis. undecimalis) 923 92 3 92.3 F 3.73 373 73 0.0001. 00001 0.0001 0 0001 0.0001) column 10°28′34.02″S 1 9 92. 3.7 37 7 0000 0.000 000 3. 0.00 00 0.0 0.

Resumo Objetivo Comparar variáveis ambientais e descritores das assembleias de peixes (composição de espécies, riqueza, dominância e diversidade) entre lagoas costeiras do sistema do rio Tramandaí, sul do Brasil. Métodos Amostras de água e de peixes foram coletadas mensalmente de Abril de 2009 a Março de 2010 na zona litoral de seis lagoas, três ao norte e três ao sul do estuário de Tramandaí. Treze variáveis ambientais de qualidade da água foram mensuradas. As capturas de peixes foram realizadas por meio de redes de emalhe. Usamos abordagem multivariada para investigar variações espaciais nas variáveis abióticas e diversidade de peixes. Resultados As amostras das lagoas ao norte (Itapeva, Quadros e Malvas) foram relacionadas com maiores valores de turbidez e demanda bioquímica de oxigênio, enquanto as amostras das lagoas ao sul (Fortaleza, Rondinha e Barros) com maiores valores de dureza, sólidos totais dissolvidos, transparência, condutividade elétrica e salinidade. As assembleias de peixes foram similares em composição de espécies entre as lagoas. A riqueza foi superior nas lagoas ao sul quando o mesmo número de exemplares foi considerado. Ao norte, as assembleias mostraram dominância numérica de Psalidodon aff. fasciatus e Loricariichthys anus, e menor diversidade, enquanto ao sul as assembleias foram mais equitativas e diversas. Conclusões Concluímos que as lagoas costeiras estudadas diferem no padrão de variação de parâmetros abióticos, refletindo em diferenças na qualidade da água. A composição e riqueza de espécies são similares e refletem a origem biogeográfica comum e recente das lagoas. As assembleias de peixes em lagoas grandes e turvas apresentam maior dominância enquanto as assembleias de peixes em lagoas pequenas e claras são mais diversificadas. Esses resultados podem ser úteis no manejo costeiro que prioriza os estoques pesqueiros ou na proposição de modelos de assembleias de peixes em lagoas costeiras subtropicais. Tramandaí Brasil 200 201 mensuradas emalhe Itapeva, Itapeva (Itapeva Malvas oxigênio Fortaleza, Fortaleza (Fortaleza Barros dureza dissolvidos transparência salinidade considerado aff anus diversas abióticos diversificadas subtropicais 20 2

Abstract Aim To compare abiotic variables and fish assemblage descriptors (species composition, richness, dominance and diversity) among coastal lagoons of the Tramandaí river system, southern Brazil. Methods Water and fish samples were taken monthly from April 2009 to March 2010 in the littoral zone of six coastal lagoons, three located at the north and three at the south of the Tramandai estuary. Thirteen environmental variables were measured. The fish assemblage samples were sampled with gillnets. We used multivariate analyses to investigate spatial variation in abiotic conditions and fish diversity. Results The samples at northern lagoons (Itapeva, Quadros and Malvas) were related to greater values of the turbidity and biochemical oxygen demand, while the southern lagoons (Fortaleza, Rondinha and Barros) were related to greater values of hardness, total dissolved solids, transparency, conductivity and salinity. The fish assemblages were similar in species composition. The species richness was higher in the southern lagoons when considering the same number of specimens. In the northern lagoons the assemblages were numerically dominated by Psalidodon aff. fasciatus and Loricariichthys anus and less diverse, while in southern lagoons were more equitable and diverse. Conclusions We concluded that the coastal lakes studied differ in the patterns of variation in abiotic parameters and this reflect in the water quality. Fish richness and species composition are similar, a likely result of the common and recent biogeographic origin of these lagoons. Fish assemblages in large and turbid lagoons present more dominance while the fish assemblages in small and clear lagoons are more diverse. These results may be useful for coastal management that prioritizes fish stocks or for proposing models of fish assemblages in subtropical coastal lagoons. diversity system Brazil 200 201 estuary measured gillnets Itapeva, Itapeva (Itapeva Malvas demand Fortaleza, Fortaleza (Fortaleza Barros hardness solids transparency salinity specimens aff diverse quality 20 2

Abstract The present study was carried out in the Muriá or Maripanema borehole estuary located in the Atlantic Coast sector of Salgado, Northern Brazil, with the objective of understanding the dynamics of the dissolved nutrients at the water-air interface and the mechanisms of their interaction with the abiotic and biotic parameters (chlorophyll a). This system is influenced by seasonality, which involves aspects of tidal regimes. For this, the spatial and temporal variability of dissolved inorganic nutrients was evaluated together with physical-chemical parameters through mixture diagrams, stoichiometric ratios, and Principal Component Analysis. Ammoniacal N was the most representative form of dissolved inorganic nitrogen in both seasons with maximum values around (~199 μM) subsidizing primary productivity, with a maximum chlorophyll value of (122 μg.m-3). The high level of N-ammonia was also associated with the release of domestic effluents, aquaculture and degradation of organic matter that occur in the mangrove areas along the Muriá borehole. Phosphate, among the dissolved nutrients, was the one that suffered the most neutralizing action, with low concentrations, so as not to offer signs of eutrophication. Silica concentrations were influenced by variations in tides and water flows. In general, the results obtained allowed an excessive intake of nutrients to be observed along the Muriá borehole, with fluctuations in their concentrations influenced by seasonality, tides and anthropic activities indicating a highly dynamic environment that directly influences the primary productivity of the region. Salgado Brazil waterair air a. . a) seasonality regimes this physicalchemical physical chemical diagrams ratios Analysis ~199 199 (~19 μM 122 (12 μg.m3. μgm3 μgm μg.m 3 μg m μg.m-3) Nammonia ammonia effluents Phosphate action eutrophication flows general region ~19 19 (~1 12 (1 m3 μg.m3 μg.m-3 ~1 1 (~ ( μg.m- ~

Resumo O presente estudo foi desenvolvido no estuário do furo do Muriá ou Maripanema, localizado no setor Costa Atlântica do Salgado, norte do Brasil, com o objetivo de conhecer a dinâmica dos nutrientes dissolvidos na interface água-ar e os mecanismos de interação desses nutrientes com os parâmetros abióticos e bióticos (clorofila a). Esse sistema sofre a influência da sazonalidade, que envolve aspectos dos regimes de marés. Para tal, foi avaliada a variabilidade espacial e temporal dos nutrientes inorgânicos dissolvidos em conjunto com os parâmetros físico-químicos por meio de diagramas de mistura, razões estequiométricas e análise de componentes principais. O N-amoniacal foi a forma mais representativa de nitrogênio inorgânico dissolvido em ambas as estações com valores máximos de ~199 μM, subsidiando a produtividade primária, com valor máximo de clorofila a de 122 μg.m-3. O elevado nível de N-amoniacal esteve associado também ao lançamento de efluentes domésticos, à aquicultura e à degradação da matéria orgânica que ocorrem nas áreas de manguezais ao longo do furo do Muriá. O fosfato, entre os nutrientes dissolvidos, foi o que mais sofreu ação neutralizadora, com baixas concentrações, de forma a não oferecer sinais de eutrofização. As concentrações de sílica sofreram influência das variações de marés e fluxos das águas. No geral, os resultados obtidos permitiram observar uma entrada excessiva de nutrientes ao longo do furo do Muriá, com oscilações em suas concentrações influenciadas pela sazonalidade, pelas marés e pelas atividades antrópicas, indicando um ambiente altamente dinâmico que influencia diretamente a produtividade primária da região. Maripanema Salgado Brasil águaar água ar a. . a) sazonalidade tal físicoquímicos físico químicos mistura principais Namoniacal N amoniacal 199 ~19 μM 12 μg.m3. μgm3 μgm μg.m 3. μg m 3 μg.m-3 domésticos fosfato neutralizadora eutrofização águas geral antrópicas região 19 ~1 1 m3 μg.m3 μg.m- ~

Abstract The construction of a data bank concerning metal and metalloid content of bioindicator fish from coastal areas is very important as it can help environmental managers in decision making. In natural conditions, the concentration of elements can be influenced by abiotic parameters such as water salinity. In this study, catfish Cathorops spixii were evaluated concerning the total arsenic (As) concentration in the muscle tissues of individuals subjected to different abiotic conditions in the Cananéia-Iguape Estuarine-Lagoon Complex (CIELC), which was recently included on the Ramsar list of wetlands of international importance. Seventy-four catfish were seasonally caught in the northern and southern regions of the CIELC and their hydrochemical parameters were obtained. C. spixii from the southern, best preserved, area showed arsenic concentrations around ten times higher than the maximum limit established for fish intended for human consumption. However, these high concentrations of arsenic could be associated with the abiotic parameters of the water, such as salinity variations, in this area. making study As (As CananéiaIguape Cananéia Iguape EstuarineLagoon Estuarine Lagoon CIELC, , (CIELC) importance Seventyfour Seventy four obtained C preserved consumption However variations (CIELC

Abstract The present study was carried out in the Muriá or Maripanema borehole estuary located in the Atlantic Coast sector of Salgado, Northern Brazil, with the objective of understanding the dynamics of the dissolved nutrients at the water-air interface and the mechanisms of their interaction with the abiotic and biotic parameters (chlorophyll a). This system is influenced by seasonality, which involves aspects of tidal regimes. For this, the spatial and temporal variability of dissolved inorganic nutrients was evaluated together with physical-chemical parameters through mixture diagrams, stoichiometric ratios, and Principal Component Analysis. Ammoniacal N was the most representative form of dissolved inorganic nitrogen in both seasons with maximum values around (~199 μM) subsidizing primary productivity, with a maximum chlorophyll value of (122 μg.m-3). The high level of N-ammonia was also associated with the release of domestic effluents, aquaculture and degradation of organic matter that occur in the mangrove areas along the Muriá borehole. Phosphate, among the dissolved nutrients, was the one that suffered the most neutralizing action, with low concentrations, so as not to offer signs of eutrophication. Silica concentrations were influenced by variations in tides and water flows. In general, the results obtained allowed an excessive intake of nutrients to be observed along the Muriá borehole, with fluctuations in their concentrations influenced by seasonality, tides and anthropic activities indicating a highly dynamic environment that directly influences the primary productivity of the region. Salgado Brazil waterair air a. . a) seasonality regimes this physicalchemical physical chemical diagrams ratios Analysis ~199 199 (~19 μM 122 (12 μg.m3. μgm3 μgm μg.m 3 μg m μg.m-3) Nammonia ammonia effluents Phosphate action eutrophication flows general region ~19 19 (~1 12 (1 m3 μg.m3 μg.m-3 ~1 1 (~ ( μg.m- ~

Resumo O presente estudo foi desenvolvido no estuário do furo do Muriá ou Maripanema, localizado no setor Costa Atlântica do Salgado, norte do Brasil, com o objetivo de conhecer a dinâmica dos nutrientes dissolvidos na interface água-ar e os mecanismos de interação desses nutrientes com os parâmetros abióticos e bióticos (clorofila a). Esse sistema sofre a influência da sazonalidade, que envolve aspectos dos regimes de marés. Para tal, foi avaliada a variabilidade espacial e temporal dos nutrientes inorgânicos dissolvidos em conjunto com os parâmetros físico-químicos por meio de diagramas de mistura, razões estequiométricas e análise de componentes principais. O N-amoniacal foi a forma mais representativa de nitrogênio inorgânico dissolvido em ambas as estações com valores máximos de ~199 μM, subsidiando a produtividade primária, com valor máximo de clorofila a de 122 μg.m-3. O elevado nível de N-amoniacal esteve associado também ao lançamento de efluentes domésticos, à aquicultura e à degradação da matéria orgânica que ocorrem nas áreas de manguezais ao longo do furo do Muriá. O fosfato, entre os nutrientes dissolvidos, foi o que mais sofreu ação neutralizadora, com baixas concentrações, de forma a não oferecer sinais de eutrofização. As concentrações de sílica sofreram influência das variações de marés e fluxos das águas. No geral, os resultados obtidos permitiram observar uma entrada excessiva de nutrientes ao longo do furo do Muriá, com oscilações em suas concentrações influenciadas pela sazonalidade, pelas marés e pelas atividades antrópicas, indicando um ambiente altamente dinâmico que influencia diretamente a produtividade primária da região. Maripanema Salgado Brasil águaar água ar a. . a) sazonalidade tal físicoquímicos físico químicos mistura principais Namoniacal N amoniacal 199 ~19 μM 12 μg.m3. μgm3 μgm μg.m 3. μg m 3 μg.m-3 domésticos fosfato neutralizadora eutrofização águas geral antrópicas região 19 ~1 1 m3 μg.m3 μg.m- ~

EVALUATING DIRECT AND INDIRECT pCO2 MEASUREMENTS IN ESTUARINE ENVIRONMENTS. Estuaries are dynamic systems globally characterized as sources of CO2 to the atmosphere. However, they present large spatial-temporal variability in both pCO2 and FCO2. Increased CO2 emissions turns imperative to obtain continuous and accurate measurements of pCO2 in air and water to monitor FCO2 in these sensitive and complex environments. Currently, direct measurements of pCO2 and estimates of FCO2 in estuarine regions are still scarce and frequently the indirect pCO2 estimates are used that consists of measurements from at least two other parameters of the carbonate system: total alkalinity, dissolved inorganic carbon or pH. In this work, we evaluated recent direct and indirect measurements of pCO2 in the Jaguaribe River estuary-CE. This study provides a critical analysis of the data obtained through the two main methods mostly used to estimate pCO2, presenting the challenges towards greater consistency in obtaining data for a better understanding of the carbonate system in estuarine waters. We highlight the potential for continuous pCO2 measurements and long-term monitoring in coastal environments, contributing to improve knowledge of regional CO2 exchanges and to elucidate the role of estuaries in the global carbon cycle. pCO ENVIRONMENTS CO atmosphere However spatialtemporal spatial temporal FCO environments Currently alkalinity pH work estuaryCE. estuaryCE estuary CE. CE estuary-CE waters longterm long term cycle

Plastic pollution is causing worldwide concern, especially after evidence that the various types of plastic degrade into particles of smaller sizes; known as micro- and nanoplastics. The origin of the plastics in the environment is related to human actions. The objective of this review is to describe the main routes of microplastic input in the Amazonian rivers and how local environmental characteristics can affect the transformation of plastics into microplastics until their absorption by aquatic organisms. The current situation regarding the presence of microplastic particles in freshwater is analyzed considering the environmental dynamics of the region, and focuses on rivers, estuaries and sediments, their effects on organisms, especially on fish, followed by the transportation of microplastic particles to the sea. Amapá, Amazonas, Pará and Mato-Grosso are the states of the Brazilian Amazon with scientific reports on the characterization of microplastic particles in sediment, water, and fish. These studies are local and descriptive and most of them highlight the characterization of microplastics. There is a need for field research in the various microregions of the Amazon, as well as actions to mitigate the damage, including to riverine populations, that is caused by these pollutants in the region. concern sizes micro nanoplastics organisms region sediments fish sea Amapá Amazonas MatoGrosso Mato Grosso sediment water damage populations