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Coastal ecosystems have ecological importance worldwide and require control and prevention measures to mitigate human pollution. The objective of this study was to perform a systematic review to provide a comprehensive overview of the global issue of coastal plastic pollution. 689 articles were eligible for qualitative synthesis and 31 were considered for quantitative analysis. There was an exponential increase in articles addressing coastal plastic pollution over the past 50 years. Studies were mainly carried out on beaches, and plastic bottles were the most found item, followed by cigarette butts. Polyethylene was the predominant plastic polymer, and white microplastic fragments stood out. China published most articles on the topic and Brazil had the highest number of sites sampled. Meta-analysis had significant effect sizes based on the reported data. These findings carry significant implications for environmental policies, waste management practices, and targeted awareness campaigns aimed at mitigating plastic pollution.

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In recent years, pelagic sargassum (S. fluitans and S. natans - henceforth sargassum) macroalgal blooms have become more frequent and larger with higher biomass in the Tropical Atlantic region. They have environmental and socio-economic impacts, particularly on coastal ecosystems, tourism, fisheries and aquaculture industries, and on public health. Despite these challenges, sargassum biomass has the potential to offer commercial opportunities in the blue economy, although, it is reliant on key chemical and physical characteristics of the sargassum for specific use. In this study, we aim to utilise remotely sensed spectral profiles to determine species/morphotypes at different decomposition stages and their biochemical composition to support monitoring and valorisation of sargassum. For this, we undertook dedicated field campaigns in Barbados and Ghana to collect, for the first time, in situ spectral measurements between 350 and 2500 nm using a Spectra Vista Corp (SVC) HR-1024i field spectrometer of pelagic sargassum stranded biomass. The spectral measurements were complemented by uncrewed aerial system surveys using a DJI Phantom 4 drone and a DJI P4 multispectral instrument. Using the ground and airborne datasets this research developed an operational framework for remote detection of beached sargassum; and created spectral profiles of species/morphotypes and decomposition maps to infer biochemical composition. We were able to identify some key spectral regions, including a consistent absorption feature (920-1080 nm) found in all of the sargassum morphotype spectral profiles; we also observed distinction between fresh and recently beached sargassum particularly around 900-1000 nm. This work can support pelagic sargassum management and contribute to effective utilisation of the sargassum biomass to ultimately alleviate some of the socio-economic impacts associated with this emerging environmental challenge.

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The Sepetiba Bay (Southeast Brazil) is a known Cd- and Zn-contaminated site that received spills of a large slag pile leachate from a Zn smelter. With important harbors, Sepetiba Bay demands periodic dredging operations which affect the mobility of the metals. The main goal of this work was to assess metal mobility in sediments and its associated toxicity in a fictive dredging area, to evaluate the risks of the operation. To achieve this goal, 18 superficial sediment samples were collected and characterized for pH and Eh. Sediments were analyzed for grain size, organic carbon, and total nitrogen, and metal mobility was evaluated with a sequential extraction procedure, proposed by the European Community Bureau of Reference (BCR). The results demonstrate that Cd and Zn are mainly associated with the exchangeable fraction (mean concentrations 1.4 mg kg-1 and 149.4 mg kg-1, respectively) and reducible fractions (mean concentrations 0.3 mg kg-1 and 65.5 mg kg-1, respectively), while Fe, Cr, Cu, Ni, and Al were associated with the residual fraction. Metals in the residual fraction are probably associated with the mineral lattice of the sediment and should not represent an environmental risk for the biota. The application of the enrichment factor and three risk assessment indexes (Risk Assessment Code, Risky Pollution Index, and Bioavailability Risk Assessment Index) show that the sediments are considerably enriched in metals that constitute a relevant risk for the sediment biota. In the case of dredging operations, Cd and Zn should be released to the overlying waters and be available to organisms, threatening the whole ecosystem. The proposed approach was shown to be much more precise than what is frequently presented in the Environmental Impact Assessments that only consider the threshold limits of the legislation.

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Breakwater construction is common on different coasts, and by means of their structural complexity these built infrastructures can trap anthropogenic litter. We investigated the temporal persistence of anthropogenic litter in breakwaters, and how fast litter accumulates on them. We sampled anthropogenic litter in old (>10 years since construction) breakwaters and in a recently upgraded one (5 months) and on rocky shores located in a coastal conurbation, in central Chile (33°S). We found breakwaters had much higher litter densities than rocky habitats, and this pattern was persistent through time (~5 years). Also, a recently upgraded breakwater had similar composition and densities of litter items as older breakwaters. Therefore, litter accumulation on breakwaters is a very fast process related to their topographic structure and to the willingness of people to dispose of anthropogenic litter in the infrastructure. Redesigning the breakwater structure is required to reduce litter accumulation on the coast and their impacts.

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Ponta Negra beach is one of the main tourist destinations in the state of Rio Grande do Norte (Brazil), which is used by many tourists. This study aimed to perform a temporal analysis of the environmental quality of the beach related to coastal erosion, considering environmental and anthropic parameters at two different times, 10 years apart. The total length of the beach (3 km) was subdivided into 10 sections of approximately 300 m numbered 1-10, from south to north. Eight parameters were assessed based on an attribute scale ranging from the worst to the best possible quality (1-4) found in each section. The sum of the parameters was used to determine the final score. To determine the level of environmental quality, four conditions were considered (excellent, good, regular, and bad). Compared with the first sampling period, the results indicated that 50% of the beach showed reduction in environmental quality. The "excellent" condition, obtained in the first sampling period for two of the sections, was not repeated in the second period. Two situations were responsible for the decrease in beach quality over time: the erosive process that took place after 2012 and consequent reduction in vegetation cover and width of the beach environment. The current state of the beach and its gradual loss of quality over the years indicate an unpromising trend towards recovery. The methodology used in this study can be easily repeated in other locations with similar problems, generating data that can help in understanding local conditions.

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Seeding native species on pillars and platforms of marinas and harbors has been suggested to reduce space availability and prevent the colonization of exotic nuisance species, which are usually associated with coastal urbanization. The efficacy of seeding, however, has been tested mainly on the intertidal zone. To test how seeding native species in the subtidal zone affects the subsequent colonization and spread of exotic species and the community diversity, we deployed 10 PVC plates seeded with adults of the native sponge Mycale angulosa, 10 with the native ascidian Symplegma rubra, both covering about 6% of the available substrate, and 10 plates free of any intervention in a recreational marina from the Southwestern Atlantic Ocean. We then assessed the diversity and structure of the sessile community across treatments after eight months. Seeding the substrate with S. rubra resulted in no difference to unseeded communities, which were dominated by the exotic bryozoan Schizoporella errata (>66% of the substrate) and supported on average 16.9 ± 1.3 and 14.2 ± 2.0 morphospecies, respectively. However, seeding the substrate with M. angulosa resulted in a distinct community dominated by the seeded sponge (>97% of the substrate) and supporting only 3.2 ± 0.5 morphospecies. Besides, all 13 registered exotic species were reported from communities seeded with S. rubra, 11 from the unseeded communities, but only three were observed in those seeded with M. angulosa. While the consequences of the low diversity of the community seeded with M. angulosa must be addressed since poor communities are usually associated with low biotic resistance to invasion, seeding resulted in a high dominance of the native sponge, reducing the monopolization of resources by exotic species. These results suggest that seeding the substrate with native species should be implemented along with other interventions for managing artificial habitats in the coastal zone.

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Classification of beaches into morphodynamic states is a common approach in sandy beach studies, due to the influence of natural variables in ecological patterns and processes. The use of remote sensing for identifying beach type and monitoring changes has been commonly applied through multiple methods, which often involve expensive equipment and software processing of images. A previous study on the South African Coast developed a method to classify beaches using conditional tree inferences, based on beach morphological features estimated from public available satellite images, without the need for remote sensing processing, which allowed for a large-scale characterization. However, since the validation of this method has not been tested in other regions, its potential uses as a trans-scalar tool or dependence from local calibrations has not been evaluated. Here, we tested the validity of this method using a 200-km stretch of the Brazilian coast, encompassing a wide gradient of morphodynamic conditions. We also compared this locally derived model with the results that would be generated using the cut-off values established in the previous study. To this end, 87 beach sites were remotely assessed using an accessible software (i.e., Google Earth) and sampled for an in-situ environmental characterization and beach type classification. These sites were used to derive the predictive model of beach morphodynamics from the remotely assessed metrics, using conditional inference trees. An additional 77 beach sites, with a previously known morphodynamic type, were also remotely evaluated to test the model accuracy. Intertidal width and exposure degree were the only variables selected in the model to classify beach type, with an accuracy higher than 90% through different metrics of model validation. The only limitation was the inability in separating beach types in the reflective end of the morphodynamic continuum. Our results corroborated the usefulness of this method, highlighting the importance of a locally developed model, which substantially increased the accuracy. Although the use of more sophisticated remote sensing approaches should be preferred to assess coastal dynamics or detailed morphodynamic features (e.g., nearshore bars), the method used here provides an accessible and accurate approach to classify beach into major states at large spatial scales. As beach type can be used as a surrogate for biodiversity, environmental sensitivity and touristic preferences, the method may aid management in the identification of priority areas for conservation.

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Plastic is one of the most commonly found residues in the marine environment, which can cause several impacts. This study evaluated the interaction of marine litter with surf-zone trammel nets in Southern Brazil. Fifty fishing operations were sampled, where 4213 items were captured: 1500 discarded fish, 1384 fragments of marine litter, and 1329 utilized fishes. Plastics were the most abundant items (n = 1363), representing 98.4% of the registered marine litter, especially plastic bags (n = 1191). 94.5% of registered marine litter is considered as single-use waste. The interaction with marine litter can cause negative impacts to small-scale fisheries (e.g. economic and damage to fishing nets). We highlight the urgency in implementing actions for urban solid waste management and public policies to reduce single-use plastics and educational campaigns on the environmental theme.

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Cumulative and synergistic impacts from environmental pressures, particularly in low-lying tropical coastal regions, present challenges for the governance of ecosystems, which provide natural resource-based livelihoods for communities. Here, we seek to understand the relationship between responses to the impacts of El Niño and La Niña events and the vulnerability of mangrove-dependent communities in the Caribbean region of Colombia. Using two case study sites, we show how communities are impacted by, and undertake reactive short-term responses to, El Niño and La Niña events, and how such responses can affect their adaptive capacity to progressive environmental deterioration. We show that certain coping measures to climate variability currently deliver maladaptive outcomes, resulting in circumstances that could contribute to system 'lock-in' and engender undesirable ecological states, exacerbating future livelihood vulnerabilities. We highlight the significant role of social barriers on vulnerabilities within the region, including perceptions of state abandonment, mistrust and conflicts with authorities. Opportunities to reduce vulnerability include enhancing the communities' capacity to adopt more positive and preventative responses based on demonstrable experiential learning capacity. However, these will require close cooperation between formal and informal organisations at different levels, and the development of shared coherent adaptation strategies to manage the complexity of multiple interacting environmental and climatic pressures.

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Early detection and rapid response plans are a set of principles to reduce the establishment, spread and impact of invasive species and it is a critical step in management in marine ecosystems. Two potentially invasive ascidians attached to the hull of a recently sunk fishing vessel were early detected in Patagonia. With the aim of assisting in the management decision-making process during the early steps of a rapid response, we conducted several analyses through different approaches. First, we identified the species through classic taxonomical and genetic analyses. Then, we evaluated the regional and international shipping connectivity to study potential donor regions and finally, we used species distribution models (SDMs) to predict the potential distribution of these species. The potentially invasive ascidians were identified as Styela clava and Styela plicata, and this is the first record for both species in the Nuevo gulf, Patagonia Argentina. Both species have a widespread distribution around the world with strong ecological and economic impacts documented. Shipping traffic analysis suggested that S. plicata could have arrived by secondary spread from regional ports, while the arrival of S. clava was likely to be associated with international shipping traffic. Furthermore, the SDM predicted that S. clava has suitable coastal areas along the entire Southwestern Atlantic shoreline, where it is currently absent. On the contrary, the SDM predicted that further southward spread of S. plicata is unlikely, being limited by the minimum annual temperature. We discussed the different approaches, tools, and expertise integrated in this work in the light of the decision-making process for the early detection of marine invasive species in the Southwestern Atlantic. Moreover, we call attention to the increased creation of artificial habitats through the intentional sinking of ships and the potential consequences of these actions in the conservation of marine ecosystems.

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The study evaluated the characteristics of marine litter disposed of by tourists on the Abaís beach (state of Sergipe, Brazil), during the dry (December/2017, January/2018, and February/2018) and rainy (May/2018, June/2018, and July/2018) months. Litter was collected on a Sunday of each month after the tourists left. The values of abundance (9.71 ± 2.03 items/m), weight (21.07 ± 16.04 g/m), volume (0.58 ± 0.25 L/m), richness (33 litter groups) and plastic percentage (75.07 ± 4.81%) were higher in the dry months compared to the rainy ones (2.01 ± 2.80 items/m; 5.08 ± 6.01 g/m; 0.17 ± 0.16 L/m; 22 litter groups; and 68.62 ± 5.98% of plastic, respectively). Considering the tourist importance of the Abaís beach to Sergipe state, it is crucial to develop effective cleaning actions, environmental awareness campaigns for tourists, residents and traders, as well as to establish restrictive public legal instruments to promote reduction, reuse, and recycling of the marine litter.

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As a result of the COVID-19 pandemic, there is an evident decrease in economic activity, especially in the tourism sector. On the southwest coast of the Buenos Aires Province (Argentina), coastal cities base their economy on 3S tourism. In this context, the analysis of social views is crucial for participatory coastal management. As well as the forecast of beach use areas in semi-diurnal mesotidal and low-slope beach conditions, wherein few hours the available beach can double or disappear. Therefore, our objective was to determine the beach's optimal use according to its tides, socio-environmental characteristics, and the perception of the interested parties about the 2020/2021 summer season in the pandemic context in Pehuén Co Beach. We employed camera images (January 2019 and 2020) to obtain the behaviour of normal, spring and neap tides, beach geomorphology, and daily and hourly beach use curves. Online surveys were also conducted with residents, second homeowners, and Pehuén Co visitors about their perception for the 2020/2021 summer season. With this analysis, we were able to divide the beach into four areas according to its potential carrying capacity. During low tide, users' maximum capacity on the beach, respecting sanitary distances, may be 6400 people. Meanwhile, at low tide, this number may rise to 34,000. This information is essential for coastal management after the COVID-19 irruption to ensure maximum efficiency in using the beach maintaining a safe social distance.

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Ports link world commerce via maritime routes, and dredging services are essential to establish and maintain these connections. However, one question is critical when dredging is being considered: where are the best places to do it? To try to answer this question, a Dredging Sensitivity Index (DSI) was developed as a management tool to be used in project planning steps. In order to diminish environmental damages and quality-of-life losses, DSI provides alternatives by identifying sensitivity areas. This new methodology quantifies impacts caused by the sediment removal step and points out favorable areas to dredge, with a simple map. Parameters such as fine-grain content (% < 63 µm), Acid Volatile Sulfides (AVS), Shannon-Wiener Index and fisheries, among others, were used to calculate the DSI. Formulas were used to weight and aggregate both, the parameters and the DSI itself. Sepetiba Bay was chosen to apply this methodology because of its relevant economic and environmental aspects. The methodology was applied to dredging situations, but it can be used to indicate areas for dredged material disposal, with a few modifications in the DSI formulas. A DSI map was a final result of this methodology, and showed that the northern portion of the bay, close to the littoral is a more sensitive area, where dredging should be avoided, or carried out very carefully. DSI is a very useful tool for reducing damages from dredging services, it contributes with zonation and it provides alternatives to decision-makers who manage these areas.

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Human interventions on coastal areas are always causing environmental impact; however, most of the times inventories of those interventions are possibly not well structured, and surely without a specific standard. The raw data presented shows an exhaustive and systematic revision of satellite images on 1700 km of the Caribbean coast of Colombia, where 2743 human interventions were identified. These interventions are classified in 38 categories in order to assess their environmental impact at a regional scale. The filtered data shows the environmental impact obtained for each category and the values allotted to each of the four parameters used for this evaluation. Moreover, the data is filtered for each of the five environmental coastal units in which the Caribbean coast of Colombia is divided by national regulations. Finally, the filtered and processed data shows the analysis done to obtain the graphical results of a previously paper (An evaluation of human interventions in the anthropogenically disturbed Caribbean Coast of Colombia [1]). Therefore, this dataset comprises three spreadsheets (xlsx) and two geographical files (kmz), which are ready to be used for any researcher, decision maker, land planner or practitioner interested in making further analysis on environmental impact assessment in coastal areas. Additionally, the dataset is carefully organised for educational exercises in such a manner that professors or lecturers can repeat the same steps in this study area or in their own, from the inventory to the final results.

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Environmental stressors such as sea-level rise, erosion, and increased storm frequency and intensity are exposing coastal properties to greater amounts of damage. Coastal habitats like beaches, dunes, seagrasses, and wetlands can help reduce exposure and property damage. Using InVEST's Coastal Vulnerability Model, an exposure index value was calculated for every 250 m2 segment along the coastline in Escambia and Santa Rosa counties in Florida, USA. Nineteen sea level-by-habitat management scenarios were evaluated for a suite of shoreline segments across multiple exposures that can be used to inform local decision making as part of larger strategies for coastal management. Overall, a rise in sea level and degradation of coastal habitats could decrease the number of lower exposed shoreline segments and increase the number of higher exposed shoreline segments. These results were used to identify changes in the amount of potential residential property damage among different scenarios. Under high sea levels, additional protection to coastal habitats could reduce the amount of residential property damage resulting from one tropical cyclone event by $50.4 million (2018 US dollars (USD)) (by the year 2050) and by $71.8 million (2018 USD) (by the year 2100) in Escambia and Santa Rosa counties. This research demonstrates the effects that habitat type/abundance and sea-level rise could have on vulnerable coastlines. The results of the modeled scenarios can be incorporated into several recent community resiliency planning initiatives in the region to develop more robust management plans and preparations for a changing environment.

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It is presented a systematic literature review of artificial reef research, including 620 studies throughout the world from 1962 to 2018. The primary focus of this study was to examine long-term trends in research, focusing on ecological and socioeconomic questions, and to develop new research directions for this field. From 1962 to the beginning of the 1990s, the United States and Japan were the main centers of artificial reef research. Subsequently, researchers in several other countries (particularly China, Australia, Italy, Brazil, and the United Kingdom) began to focus on this subject, resulting in an increase in the number of artificial reef studies. In general, publications about artificial reefs have concentrated on investigating the structure of populations and marine communities and evaluating new technical designs and materials to construct artificial habitats. The science of artificial reefs is responding to new challenges with an increase in more elaborate techniques, such as the use of remotely-operated submarines, organic indicators, isotopes, and molecular biology, while research that evaluates the socioeconomic aspects of artificial reefs is lacking. There are many aspects that deserve more research attention, such as the use of alternative inert materials, environmental impact assessment and mitigation, and analysis of conflicts with affected fisheries communities. The greater challenge is to overcome the apparent division between theory vs. application and to include robust management models of these artificial environments.

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We present an alternative approach for establishing in situ bioaccumulation assessment of methyl-Hg (MeHg), total-Hg, Cd, Pb and Zn in bivalve Anomalocardia brasiliana from four bays of Rio de Janeiro presenting varying degrees of eutrophication, acid volatile sulfides (2-55 µmol g-1), simultaneously extracted metals (SEM) and total metals (TM) in sediments. Using metal concentrations of composite samples from three size classes of bivalve and their incorporation rates (IR = metal concentration / total length), which depend on exposure time, we calculated asymptotic IR and respective consequent metal concentrations. Both IR and the metal concentration presented inverse relationships with total length (excepting MeHg) and bay contamination. Lead and zinc concentrations were above Brazilian legal criteria in the most anoxic and contaminated bay, suggesting significant metal bioavailability (SEM/TM between 8% and 63%).

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We investigated the relationship between the AMBI index and different contamination proxies in an urbanized bay in South America (SE Brazil), and the effect of (a) abundance data transformation and (b) exclusion of low-reliability sites (high SD; low N) on the index' performance. Poor ecological quality and opportunistic species were related to an increase in contaminants concentrations and mud content. Good ecological status and sensitive species (EG I) were mainly related to increased hydrodynamics. Data transformation caused minimal changes to the overall relationships, but exclusion of low-reliability sites improved the relationship between ecological groups and contamination proxies. Our results show that AMBI is robust in detecting effects of different contaminants in the area and reinforce the importance of the index as a tool for coastal management, but local joint efforts are needed to improve and adjust local species classification in ecological groups to improve the index' performance.

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Ocean thermal energy conversion (OTEC) is a form of power generation, which exploits the temperature difference between warm surface seawater and cold deep seawater. Suitable conditions for OTEC occur in deep warm seas, especially the Caribbean, the Red Sea and parts of the Indo-Pacific Ocean. The continuous power provided by this renewable power source makes a useful contribution to a renewable energy mix because of the intermittence of the other major renewable power sources, i.e. solar or wind power. Industrial-scale OTEC power plants have simply not been built. However, recent innovations and greater political awareness of power transition to renewable energy sources have strengthened the support for such power plants and, after preliminary studies in the Reunion Island (Indian Ocean), the Martinique Island (West Indies) has been selected for the development of the first full-size OTEC power plant in the world, to be a showcase for testing and demonstration. An OTEC plant, even if the energy produced is cheap, calls for high initial capital investment. However, this technology is of interest mainly in tropical areas where funding is limited. The cost of innovations to create an operational OTEC plant has to be amortized, and this technology remains expensive. This paper will discuss the heuristic, technical and socio-economic limits and consequences of deploying an OTEC plant in Martinique to highlight respectively the impact of the OTEC plant on the environment the impact of the environment on the OTEC plant. After defining OTEC, we will describe the different constraints relating to the setting up of the first operational-scale plant worldwide. This includes the investigations performed (reporting declassified data), the political context and the local acceptance of the project. We will then provide an overview of the processes involved in the OTEC plant and discuss the feasibility of future OTEC installations. We will also list the extensive marine investigations required prior to installation and the dangers of setting up OTEC plants in inappropriate locations.

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Estuários possuem relevante importância ecológica na zona costeira, abrigando comunidades bentônicas de expressivo papel na produtividade secundária. Efeitos de atividades antrópicas nestes ecossistemas podem ser evidenciados por meio de programas de monitoramento ambiental, os quais são aprimorados a partir da utilização de poliquetas, organismos susceptíveis a distúrbios. O conhecimento da distribuição destes invertebrados em planícies lamosas, incluindo seus padrões de zonação, se mostra fundamental para a elaboração de delineamentos amostrais eficientes. Desta forma, o presente trabalho objetivou investigar o padrão de zonação de três famílias de poliquetas (Nereididae, Spionidae e Capitellidae) em planícies lamosas do complexo portuário-estuarino de Santos (SP). Os organismos foram coletados em três zonas nas planícies lamosas: franja do infralitoral (ZI), porção intermediária do mesolitoral (ZM) e a franja do supralitoral (ZS). Os resultados evidenciaram um padrão de zonação, considerando as famílias Nereididae e Capitellidae, sendo que as assembleias variam seus padrões ao longo do tempo. Foi observado que a zona predominante destes organismos corresponde às porções superior e média da planície (ZS e ZM), sendo os mesmos encontrados em baixas densidades na porção inferior (ZI). Apenas a Família Spionidae não apresentou nenhum padrão de zonação, sendo sua distribuição variável ao longo do tempo. Nesse sentido, a presente contribuição traz evidências de que programas de monitoramento com coletas focadas na porção inferior das planícies lamosas podem não englobar satisfatoriamente as assembleias de Nereididae e Capitellidae. Tal fato deve ser considerado visando não comprometer a identificação precisa das variações nas comunidades macrobentônicas e, consequentemente, dos impactos antrópicos na região.(AU)

Estuaries have significant ecological importance in the coastal zone, sheltering macrobenthic communities with expressive role in secondary productivity. Effects of human activities in these ecosystems can be evidenced through environmental monitoring programs, which are improved by the use of polychaetes, organisms susceptible to variations. The knowledge about these invertebrates distribution in muddy flats, including their zonation patterns, is essential for the development of efficient sample designs. Thus, this study aimed to investigate the zonation pattern of three polychaetes families (Nereididae, Spionidae and Capitellidae) in muddy flats of Santos (SP) Port-estuarine complex. The organisms were collected in three areas in muddy flats: infratidal fringe (ZI), mesotidal intermediate portion (ZM) and supratidal fringe (ZS). The results showed a zonation pattern, considering the Nereididae and Capitellidae families. Assemblies vary their patterns over time. It was observed that the predominant area of these organisms correspond upper and middle of the flats (ZS and ZM), and they are found in low densities in the lower portion (ZI). Only the family Spionidae did not show any zonation pattern and its distribution was variable over time. In this sense, the present contribution brings evidences that monitoring programs focusing on sampling in the lower portion of muddy flats do not include satisfactorily the Nereididae and Capitellidae assemblies. This fact must be considered in order not to compromise the accurate identification of variations in the macrobenthic community and, consequently, of human impacts in the region.(AU)

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