ABSTRACT Chile has a relatively long history of monitoring and managing large-scale commercial fish stocks. However, many other small-scale fisheries, particularly those operating in estuaries, usually lack basic fisheries and biological information. International experience indicates that a monitoring system designed for large-scale stocks cannot simply be resized to address the complexity, relatively low total economic value, and the large number of actors and supply chains in small-scale fisheries. This article proposes a strategy to monitor data-poor fisheries operating in estuaries. The striped mullet (Mugil cephalus), locally known as "lisa", in the Rapel River, central Chile, was selected to establish a pilot monitoring program for small-scale fish resources. From May 2022 to May 2023, fisheries information, including fleet description, catch and effort data, and fish biological attributes such as length and weight, were collected and described for the first time in the region. Drawing insights from this case study, we propose developing a generic monitoring system tailored specifically for monitoring fish stocks in estuaries. This conceptualization is based on: i) change agents, who are individuals trained to work with both the social and biological dimensions of each coastal fish stock; ii) experienced fisheries scientists outside government agencies; and iii) local fishers’ knowledge to provide constant feedback for adapting temporal and spatial scales for monitoring. This monitoring scheme is cost-effective and can be efficiently replicated in other estuarine fisheries in Chile.

Abstract: The unplanned and fragmented urban development of cities has caused them to be responsible for most of the planet's unsustainable development. Urban sustainability emerges as a response to this imbalance. Throughout its history, Guayaquil has shown unplanned urban growth that has continuously degraded its natural resources, such as forests and estuaries. The present research aims to evaluate the level of sustainability resulting from such change at the neighborhood level in Guayaquil. The study analyzes urban indicators of six representative neighbourhoods of the city regarding socioeconomic and historical factors. Thus, indicators were analyzed with respect to form, diversity, mobility, and environmental quality. The methodology includes an analysis for selecting variables, a study of the neighbourhoods' morphology using geo-portal map and information gathering through field studies and data processing. The results allow inferring the variables' influence on the sustainability level of each analyzed neighbourhood and how density, diversity and environmental quality play a vital role in developing greater sustainability at the neighbourhood and city levels.

Resumen: El desarrollo urbano no planificado y fragmentado de las ciudades ha ocasionado que estas sean responsables de la mayor parte del desarrollo no sustentable del planeta. La sostenibilidad urbana surge como medida de respuesta ante esta descompensación. La ciudad de Guayaquil presenta a lo largo de su historia un crecimiento urbano no planificado que continuamente ha degradado sus recursos naturales, como bosques y esteros. La presente investigación tiene como objetivo evaluar el nivel de sostenibilidad resultante de tal crecimiento a nivel barrial en Guayaquil. El estudio analiza indicadores urbanos de seis barrios representativos de la ciudad en cuanto a factores socioeconómicos e históricos. Se analizaron indicadores con respecto a la forma, diversidad, movilidad y calidad ambiental. La metodología utilizada recoge un análisis para la selección de variables, estudio de la morfología de los barrios realizada por medio de mapas de geo portales, relevamiento de información a través de estudio de campo y procesamiento de datos. Los resultados permiten inferir la influencia de las variables en el nivel de sostenibilidad de cada uno de los barrios analizados y como la densidad, la diversidad y calidad ambiental desempeñan un papel primordial en el desarrollo de una mayor sostenibilidad a nivel barrial y de ciudad.

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.

ABSTRACT Overfishing, industrial fishing and climate change generate impacts that affect the marine fishery resource, the main source of income and food for coastal populations of artisanal fishers. The creation of conditions that increase the adaptive capacity of fishers will decrease their vulnerability to impacts. This research proposes to determine an Exclusive Zone for Artisanal Fishing-ZEPA as a strategy for sustainable management of fishery resources and climate adaptation for artisanal fishers in the study area. Marxan was used to identify three scenarios for the location of the ZEPA and participatory mapping was carried out with fishers to obtain the fourth scenario. High similarity was found between scenarios 2 and 4, which shows that the scientific (Marxan) and participatory (population) approaches coincide in the location of the ZEPA. The final ZEPA was located in the coastal marine zone of the municipalities of Tumaco and Francisco Pizarro, with a total area of 2,008 km2. Included important conservation targets for artisanal fisheries such as artisanal fishing grounds, ecosystems (mangroves, beaches and estuaries), areas of occurrence of species (seerfish, snappers, sea bass, piangua, marmoset shrimp) among others. More than 80 % of the fishers agreed that the strategy would help reduce their vulnerability to threats such as climatic phenomena, overfishing, pollution, among others. The contribution to climate change adaptation of the study area’s population is highlighted.

RESUMEN La sobrepesca, la pesca industrial y el cambio climático generan impactos que afectan al recurso pesquero marino, la principal fuente de ingreso y alimento de las poblaciones costeras de pescadores artesanales. La creación de condiciones que incrementen la capacidad de adaptación de los pescadores disminuirá su vulnerabilidad a los impactos. Esta investigación propone determinar una Zona Exclusiva de Pesca Artesanal-ZEPA como estrategia de manejo sostenible de los recursos pesqueros y de adaptación climática para los pescadores artesanales del área de estudio. Se utilizó el programa Marxan para identificar tres escenarios para la ubicación de la ZEPA y se realizó una cartografía participativa con pescadores para obtener el cuarto escenario. Se encontró similitud alta entre el escenario 2 y 4, lo que muestra que el enfoque científico (Marxan) y participativo (población) coinciden en la ubicación de ZEPA. La ZEPA definitiva se ubicó en la zona marino costera de los municipios de Tumaco y Francisco Pizarro, con un área total de 2 008 km2. Incluyó objetos de conservación importantes para la pesca artesanal como caladeros de pesca artesanal, ecosistemas (manglares, playas y estuarios), áreas de ocurrencia de especies (sierra, pargos, corvina, piangua, camarón tití), entre otros. Se identificó que más de 80 % de los pescadores estuvo de acuerdo en que la estrategia le aportaría a reducir su vulnerabilidad frente a amenazas como fenómenos climáticos, sobrepesca, contaminación, entre otros. Se resalta la contribución a la adaptación al cambio climático de la población del área de estudio.

ABSTRACT Abstract: Rhithropanopeus harrisii (Brachyura, Panopeidae) is a small euryhaline and eurythermal omnivorous crab native to the Northwest Atlantic. However, it has become an invasive species in various estuaries and coastal areas far from its original habitat, most likely due to intercontinental shipping. Once it establishes itself in one location, it can spread to neighboring regions via maritime currents. In 1982, this species was found in South America, specifically in Lagoa dos Patos, Brazil. In this study, we present the first record of R. harrisii larvae in Uruguay, located in the coastal marine zone of Laguna de Rocha, approximately 300 km south of Lagoa dos Patos. It was discovered during a study that involved 15 plankton samplings, conducted from February 2016 to February 2017. Notably, the observation of R. harrisii larvae was limited to the coastal zone during the summer and autumn of 2016 (February to April). All observed larvae were in the zoeal stage, and their abundance ranged from three to 185 individuals per 100 m3. The temperature and salinity values recorded during sampling surveys with the presence of R. harrisii ranged from 19 to 22.4 °C and 11.8-32.5 ppt, respectively. The discovery of the larval stage suggests that adults of this species may be reproducing in the eastern coastal zone of Uruguay or nearby regions. The area in which they are currently found could potentially serve as a biological corridor, facilitating their spread to other estuaries of great economic and ecological importance, such as the Río de la Plata, as well as other coastal lagoons and subestuaries in Uruguay and Argentina. Further monitoring studies are necessary to determine whether this species became established in the area. Potential ecological consequences in our region derived from its presence are herein discussed. Abstract Brachyura, Brachyura (Brachyura Panopeidae Atlantic However habitat shipping location currents 1982 America Patos Brazil R Rocha 30 1 samplings 201 2017 Notably April. April . April) 18 10 m3 m 224 22 4 22. C 11.832.5 118325 11.8 32.5 11 8 32 5 11.8-32. ppt respectively corridor importance Plata Argentina discussed 198 3 20 2 832 11.832. 11832 118 11. 325 32. 11.8-32 83 11.832 1183 11.8-3 11.83 11.8-

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 A migração de aves é um fenômeno que leva milhares de indivíduos a se deslocarem entre diferentes áreas de alimentação e reprodução, podendo esses movimentos ultrapassarem fronteiras geopolíticas. Este é um comportamento crucial para a sobrevivência de muitas espécies. No entanto, os impactos antrópicos estão afetando os habitats das espécies, contribuindo para o declínio populacional das aves. Diante disto, este estudo teve como objetivo analisar os distúrbios causados pelas atividades turísticas sobre as aves migratórias que visitam os estuários dos rios Cardoso e Camurupim, no litoral do estado do Piauí, e propor medidas para mitigar as perturbações sobre as aves. As amostragens foram realizadas em três pontos de observação, onde foram analisadas as alterações do comportamento das aves em repostas às atividades turísticas. Para isto, foram utilizados binóculos, câmera fotográfica e um telêmetro a laser para auxiliar na elaboração das zonas de impacto. Embora ocorram diversos tipos de atividades turísticas na região, as principais perturbações são causadas pelo kitesurf e turistas caminhando próximo às áreas de alimentação ou repouso das espécies. Calidris minutilla, Calidris pusilla, Calidris alba, Actitis macularius e Charadriius semipalmatus foram as espécies menos sensíveis aos distúrbios, reagindo com mais frequência dentro das zonas de impactos Z = 0-30m e Z = 30-60m, ao passo que as espécies Pluvialis squatarola, Numenius hudsonicus, Tringa melanoleuca, Calidris canutus, Limnodromus griseus e Pandion haliaetus apresentaram maiores distâncias de fuga. Os resultados deste estudo mostram que a presença de turistas caminhando e a prática do kitesurf são as principais atividades que impactam as aves migratórias na região, o que demonstra a necessidade de medidas para mitigar tais impactos. Com base nos resultados deste estudo, a criação de zonas de proteção mínima de 160m e 200m são indicadas para mitigar os distúrbios provocados pela aproximação de banhistas e kitesurfistas. reprodução geopolíticas entanto disto Camurupim Piauí observação isto binóculos impacto região minutilla pusilla alba 030m m 0 30m 3060m, 3060m 30 60m, 60m 30-60m squatarola hudsonicus melanoleuca canutus fuga kitesurfistas 3

Abstract The bird migration phenomenon makes thousands of individuals displace between different sites for feeding and breeding purposes. These displacements often make these birds cross geopolitical borders. This behavior is crucial for the survival of many species; however, anthropogenic impacts affect their habitats and contribute to bird-population decline. In light of the foregoing, the aims of the present study are to analyze disturbances caused by touristic activities over migratory birds who visit the estuaries of Cardoso and Camurupim rivers on the coast of Piauí State, and to suggest measures aimed at mitigating disturbances over birds. Samples were collected at three observation points to analyze changes in bird behavior, in response to touristic activities in these sites. Binoculars, a camera and a laser rangefinder were used to help drawing impact zones. Although several touristic activities are performed in the herein assessed region, the main disturbance in it is caused by both kitesurf practitioners and tourists who walk by these species’ feeding or resting zones. Calidris minutilla, Calidris pusilla, Calidris alba, Actitis macularius and Charadriius semipalmatus were the species least sensitive to disturbances, and they more often reacted to them within impact zones Z = 0-30m and Z = 30-60m, whereas species Pluvialis squatarola, Numenius hudsonicus, Tringa melanoleuca, Calidris canutus, Limnodromus griseus and Pandion haliaetus flee to distances. Based on the current results, kitesurfing and tourists walking by these sites account for the main impact on migratory birds in this region. This finding highlights the need of taking measures to mitigate such impacts. Accordingly, creating minimum protection zones to cover distances ranging from 160m to 200m radius is a recommendation to mitigate disturbances caused by bathers and kitesurf practitioners’ approaching. purposes borders however birdpopulation population decline foregoing State Binoculars region minutilla pusilla alba 030m m 0 30m 3060m, 3060m 30 60m, 60m 30-60m squatarola hudsonicus melanoleuca canutus results Accordingly approaching 3

ABSTRACT This study evaluates the applicability and reliability of the ABC method as an indicator of the level of organic pollution in non-vegetated tidal flats in a subtropical estuary in southern Brazil. Following a hierarchical sampling design, the method was applied in two contaminated and two non-contaminated tidal flats near Paranaguá. It was conducted in three consecutive fortnights of a summer and a winter, aiming to analyze correlations between faunal responses and chemical indicators of contamination and spatio-temporal variability. Tidal flats closer to the city were classified as grossly contaminated. However, the responses on the non-contaminated area were highly heterogeneous, indicating that natural inputs of organic matter were confounded with pollution effects. In the AIC analysis applied to the W-statistics of the ABC curves, the best model showed correlations with some of the fecal steroids and total organic carbon. Contrary to expected, the ABC curves significantly varied at the smaller spatio-temporal scales due to the high local hydrodynamics and natural organic inputs. This suggests that the ABC method is indeed sensible to the contamination levels and can be used as an index of biotic quality. However, the method must be cautiously applied in estuaries subjected to natural organic enrichment. nonvegetated non vegetated Brazil design noncontaminated Paranaguá winter spatiotemporal spatio temporal variability However heterogeneous effects Wstatistics W statistics carbon expected quality enrichment

ABSTRACT Promoting inclusive and effective governance in regional estuaries offers an encompassing challenge within the scope of Policy analysis and its interactions within socioecological research. The integrated approach for both theoretical elements has not easily been improved, despite the increase in analytical frameworks in this theme. The Paranaguá Bay Zone (PBZ) in the state of Paraná, Brazil, is composed of a few cities, several large, protected areas, and traditional communities. On the one hand, the intensification of real estate pressures in a low demographic region is creating a wave of value conversion regarding the trends of the coastal gentrification phenomenon, notwithstanding the lower degree of intensity when compared to other Brazilian estuaries. On the other hand, it shows a lack of political representation and institutional action at the subnational level. This asymmetrical process is strongly related to historical land development and the controversial process of implementing protected areas and zoning tools. Promoting the economic rise of the territory has affected traditional communities and conservation management, requiring permanent improvement in the ability for community mobilization and juridical vigilance in the face of impacts related to such pressure. In the meantime, scholars have considered knowledge building, which brings up assessment issues on how the decision-making process has been operated and what gaps and asymmetries can be revealed for further resilience analyses. This study is an effort to approach the performance of participative governance of the estuary and is restricted to a preliminary assessment of the participative management committees designed by legislation under area-based attributions. This study is not aimed at exploring the belief systems of different social groups/stakeholders. Results have a great emphasis on methodological building and testing, which revealed the importance of imposing an inventory and hierarchy model on the multiple committees of governance and their sectorization across adjacent areas. Results also underline variables of interest and pilot indicators in the subject under analysis. Preliminary results point to the need for overcoming methodological challenges, and findings that are useful as first evidence in the comprehension of the low performance by different committees, which often operate without any regular, systematic, integrated, transparent, legitimate, and permanent agenda of Policy activities for the PBZ fisheries territory. Qualitative data and institutional memoirs should be available and categorized in government programs, whereas research efforts that look to better recognize the idiosyncrasies of community realities under the pressures of non-transparent economic drivers are much needed. improved theme (PBZ Paraná Brazil cities large hand phenomenon level tools pressure meantime decisionmaking decision making analyses areabased area based attributions groupsstakeholders groups stakeholders groups/stakeholders testing challenges regular systematic transparent legitimate programs nontransparent non needed

Resumen: Desde su fundación, el centro de Guayaquil se vio caracterizado por la presencia de dos asentamientos, la Ciudad Vieja y la Nueva, separados por esteros y terrenos baldíos. Los incendios destruyeron la ciudad, pero permitieron un nuevo trazado urbano que unió los sectores indicados. Estas áreas intermedias se mantuvieron con un desarrollo retardado que perdura hasta la actualidad. En este contexto, el análisis de tales sectores adquiere relevancia como medida de rescate de áreas deprimidas del centro. Para lograr este objetivo, se realiza una evaluación de la sostenibilidad en dos parroquias urbanas del centro, estableciendo propuestas de densificación para fortalecer la habitabilidad y recuperación urbana y social del sector. La metodología revisa normativas de edificación, un análisis morfológico-espacial de variables y una evaluación de caminabilidad. El estudio concluye con una reflexión crítica sobre los alcances y limitaciones del enfoque adoptado y la necesidad de integrar diversas propuestas y visiones para la revitalización del centro.

Abstract: Since its foundation, the center of Guayaquil has been characterized by the presence of two settlements, the Old and the New City, separated by estuaries and vacant lots. The fires destroyed the city, but allowed a new urban layout that linked the indicated sectors. These intermediate areas remained with a delayed development, which lasts until today. In this context, the analysis of such sectors acquires relevance, as a measure to rescue depressed areas of the center. To achieve this objective, a sustainability assessment is performed in two central urban parishes, establishing densification proposals to strengthen the habitability and urban and social recovery of the sector. The methodology reviews building regulations and includes a spatial-morphological analysis of variables and a walkability study. The study concludes with a critical reflection on the scope and limitations of the approach adopted and the need to integrate various proposals and visions for the revitalization of the center.

The City of Cape Town experienced a serious drought between 2016 and 2018 which led to severe water shortages and concerns for the environment. This study took advantage of a period of unprecedented levels of awareness about water security in order to investigate households' willingness to pay (WTP) for reliable water supply and their WTP to avoid environmental damages in securing this supply. Increasing the supply of water from dams and groundwater will ultimately impact on aquatic ecosystems, but alternatives are more expensive. We surveyed 248 households from 105 suburbs and used contingent valuation methods to investigate WTP for both secure and less damaging or 'greener' ways of supplying water. Depending on income level, households were willing to pay 63-127% more for their normal levels of consumption in order to have security of supply, and a further 35-68% more to ensure its environmental sustainability. Based on the relationship between WTP for 7 income categories, the overall WTP for secure water supply under non-drought conditions amounted to some 2.8 billion ZAR/year, which is about 90% higher than pre-drought revenues. Aggregate WTP for securing this supply using options that ensured the protection of the region's rivers and estuaries was 3.3 billion ZAR. These results have an important bearing on water investment and pricing decisions over the longer term.

Knowledge about the diversity of coastal amphipods in the eastern tropical Pacific, including the Pacific coast of Colombia, is scarce. We characterized amphipod diversity in Bahía Málaga (intertidal and subtidal rocky shores, and sandy beaches) and Bahía Buenaventura (intertidal rocky shores, mangrove roots, and sandy beaches), two important estuaries in the central Pacific coast of Colombia. Sixteen species in eleven families were found; Hourstonius baciroa, Leptocheirus rhizophorae, Leucothoe alata, Elasmopus ocoroni, Melita bousfieldi, and Neomegamphopus heardi represent new records for Colombia.

El conocimiento acerca de la diversidad de los anfípodos costeros en el Pacífico Oriental Tropical, incluyendo las costas del Pacífico de Colombia, es escaso. Por esto, caracterizamos la diversidad de anfípodos en Bahía Málaga (costas rocosas intermareales y submareales, playas arenosas) y Bahía Buenaventura (costa rocosa intermareal, raíces de manglares, playas arenosas), dos estuarios importantes de la costa central del Pacífico de Colombia. Se encontraron 16 especies en once familias, de las cuales Hourstonius baciroa, Leptocheirus rhizophorae, Leucothoe alata, Elasmopus ocoroni, Melita bousfieldi y Neomegamphopus heardi representan nuevos registros para Colombia.

ABSTRACT Iphigenia brasiliensis is a bivalve mollusk exploited as a shellfish and subsistence resource on the Brazilian coast, mainly in the north and northeast regions. Genetic (allozyme electrophoresis revealed eight gene loci) and morphological variations (multivariate morphometry of valves used 13 linear measurements of traditional and 19 Fourier coefficients of geometric morphometry) were studied, considering the geographic (445 km of the southwest tropical Atlantic), environmental (mangroves and channels of communication with the sea of three estuaries in the state of Rio de Janeiro), and temporal dimensions (over two years). I. brasiliensis showed high levels of genetic variation (the average number of alleles per locus ranged from 2.8 to 3.4, and the average heterozygosity ranged from 0.441 to 0.675). Bayesian analysis of population partitioning showed that the highest LnP(D) value was achieved for K = 3. These results indicated mixed ancestry, possibly oscillations in the dispersion dynamics among the different sampling groups, and temporal oscillations in the population sizes due to the anthropogenic influence on the studied estuaries. The results of morphological variation, inferred by the PERMANOVA from the Fourier analysis, indicated that a similar influence might occur in valves (also, the discriminant analysis showed that different groups could be consistently identified). In this sense, the studied populations may be organized in a dynamic of metapopulations. Finally, these are the first data on morphological and genetic variation of the species in the latitudinal, environmental, and temporal dimensions studied simultaneously, thus providing relevant information for the exploration, management, and conservation of this commercially important species.

Resumo Estuários recebem entradas diárias de elementos químicos, que podem impactar a qualidade de água e do sedimento, assim como a saúde da biota. Além do sedimento, moluscos bivalves têm sido utilizados no monitoramento químico desses sistemas. Neste estudo investigou-se a presença e os teores de As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb e Zn no sedimento superficial e em bivalves (Crassostrea gasar, C. rhizophorae e Mytella guyanensis) de estuários do sul / extremo sul do estado da Bahia, Nordeste do Brasil. As amostras foram avaliadas por espectrometria de emissão óptica de plasma indutivamente acoplado (ICP-OES, Varian 710). Exceto Cd, todos os demais elementos foram encontrados nas amostras, sendo que Co foi exclusivo no sedimento. Os estuários equivalentes às estações amostrais #1 - Valença, #2 - Taperoá, #3 - Ilhéus e #4 - Belmonte mostraram níveis de metais compatíveis com os estabelecidos pela legislação brasileira, porém, a #5 - Santa Cruz Cabrália, além da presença de As, apresentou alto nível de Pb e de Cu em C. gasar, o que foi atribuído aos impactos por atividades náuticas nesse local.

Abstract Estuaries receive daily inputs of chemical elements which can impact the quality of water and sediment, as well as the health of biota. In addition to the sediment, bivalve mollusks have been used in the chemical monitoring of these systems. This study investigated the presence and contents of As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in superficial sediment and in bivalves (Crassostrea gasar, C. rhizophorae and Mytella guyanensis) from estuaries in the south / extreme south of Bahia State, northeast Brazil. The samples were evaluated with inductively coupled plasma optical emission spectrometry (ICP-OES, Varian 710). Except for Cd, all other elements were found in the samples, being that Co was exclusive in the sediment. The estuaries equivalent to sampling stations #1 - Valença, #2 - Taperoá, #3 - Ilhéus and #4 - Belmonte showed levels of metals compatibles with those established by the Brazilian legislation, however, the #5 - Santa Cruz Cabrália, in addition to the presence of As, presented a high level of Pb and Cu in C. gasar, which was attributed to the impacts of nautical activities in that locality.

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- ~