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The richness and biomass distribution of mangrove macroalgae were evaluated along the main salinity gradient of the Paranaguá Bay subtropical estuarine complex in southern Brazil. We used a spatially hierarchical design to investigate the spatial scales that contributed most to the variation in richness and biomass within the association. A total of eighteen taxa of macroalgae and cyanobacteria were identified with nonlinear patterns of distribution. While richness correlated with the salinity gradient, algal biomass did not follow the predicted pattern. Conversely, most of the mangrove macroalgae distribution patterns were more related to small-scale processes than to salinity variation. These results indicated that even though coastal regions are exposed to large-scale environmental processes, the somewhat disregarded small-scale processes should be also considered to unravel patterns in biological distributions.

Los poliquetos (Annelida) son organismos en íntimo contacto con el sedimento donde viven y el agua sobrenadante. El estrés ambiental genera rápidas respuestas en estos organismos que se refleja en los individuos y sus poblaciones, por lo que se utilizan como indicadores biológicos de disturbios y de calidad ambiental. Los poliquetos han sido ampliamente utilizados en monitoreo ambiental y en bioensayos, y muchos estudios ecotoxicológicos se realizan con poliquetos. En casi todos los hábitats bentónicos estos organismos juegan un papel muy importante en la organización y estructura de las comunidades bentónicas y redes tróficas. Son un ítem fundamental en la alimentación de otros invertebrados y de aves migratorias y peces. Los poliquetos también tienen importancia económica para la industria farmacéutica, y de alimentos concentrados para especies marinas de cultivo (peces y crustáceos), en el campo médico y en la bioingeniería, además de la recreativa (acuarofilia, carnada) y por supuesto para el consumo humano. Varios de los índices de impacto ambiental y calidad ambiental existentes se basan en las características de tolerancia/sensibilidad de los organismos bentónicos, y muchos de ellos son poliquetos. Existen unos pocos trabajos de revisión de estos organismos como indicadores, pero todos en idioma inglés. Este trabajo muestra una actualización de los datos referidos a Latinoamérica y el Caribe, e incluye una amplia revisión bibliográfica.

Vulnerability of small-scale fishers in the north coast of Paraná State, Southern Brazil, has been increasing due to a decline in catches and general problems of access to and management of natural resources, associated with biodiversity conservation policies. The predicted effects of climate change will represent an additional source of disturbance on local livelihoods. This study aimed to describe vulnerability of fishers and their adaptation strategies to ongoing reductions in catches, considered an analogue of possible responses to expected effects of climate change, and to evaluate the influence of no-take protected areas on them. Interviews were applied to 213 households, in 9 villages from Guaraqueçaba, in the Paranaguá Estuarine Complex. Results show that vulnerability varies in different spatial levels, mainly due to differences in the reliance on fisheries as a source of income, and in distribution of physical and social capital. Protected areas, if not adequately managed, can have a double negative effect on more vulnerable households, by restricting their access to mangrove resources in the present, and by limiting the viability of their favoured adaptation strategy for the future. These results are potentially useful for the development of biodiversity conservation and fisheries management actions adequate to the local level, and that contribute to reduce inequality and build resilience of fishers and the coastal ecosystems they rely on, in a scenario of declining fisheries and climate change.

We used morphological data for a phylogenetic analysis of the genus Petaloptoctus (Maldanidae: Polychaeta). We found three most parsimonious phylogenetic trees with length = 37, CI = 0.89 and RI = 0.92. The genus Petaloproctus is monophyletic, and is supported by a strongly arched prostomium, pinnate capillary setae, and an anal cup with a reduced dorsal border. Our proposal for the systematisation of the subgroups of Petaloproctus is ((P. tenuis (P. terriculus + P. neoborealis)) (P. ornatus (((P. cirratus + P. dentatus) (P. macrodentatus (P. borealis (P. vallejoi n. sp. + P. socialis)))))). We also regard Nicomachinae as a monophyletic group with the following synapomorphies: prostomium short and arched; nuchal grooves short and curved; cephalic plate lost; anal pore opening on margin of anal plate. Monophyly of Micromaldane and Nicomache was also supported in the analysis. Petaloproctus vallejoi n. sp. has 19 setigerous and one asetigerous pre-anal segment. The prostomium is rounded, forming a keel with curved laterals. Nuchal grooves are short and deep, strongly curved outwards. Each neuropodium has one acicular spine on setigers 1-3. The pygidium has a large ventral border, and a reduced dorsal border. The anus is terminal, and close to the margin of the anal plate, surrounded by divergent folds.

The biogeography of Terebellidae (Polychaeta) using Parsimony Analysis of Endemism (PAE) is investigated and species and genera distribution in relation to coastal and continental shelf areas of endemism around the world is considered. Hierarchical patterns in PAE cladograms are identified by testing for congruence with patterns derived from cladistic biogeography and geological evidence. The PAE cladogram indicates that many of the extant terebellid worms from the current Southern Hemisphere (“Gondwanan clades”) have originated from Laurasian ancestors or, in the case of the clade formed by Brazilian, South Atlantic and Antarctic taxa, have descended directly from an ancestral lineage common to some Northern areas. The present analysis also shows a high level of endemism at the species level. Relationships of the areas differ slightly from previous biogeographical analyses applied to other polychaete families.

O arrastão de praia, que tem na tainha seu principal alvo, é uma das mais antigas formas de pesca aindapraticadas no litoral do Paraná. Este artigo aborda aspectos da gestão patrimonial dessa pescaria, comênfase sobre as causas de seu declínio, segundo a percepção dos próprios pescadores. A abordagem foietnoecológica, empregando observação direta, aprendizado vivenciado e entrevistas semiestruturadas com13 informantes especialistas. Estes não consideraram que a prática leve à sobre-exploração do recurso,mas mostraram um senso de conservação baseado em considerações econômicas. Uma mentalidadeconservacionista surgiu muito recentemente, em decorrência das constatações empíricas de redução daabundância de peixes. A inserção de novas tecnologias de pesca mais produtivas e rentáveis contribuiupara as mudanças nos regimes de acesso aos recursos (caracterizadas principalmente pelo desrespeitoàs regras informais de uso). Uma ruptura de valores fomentou a competição, que se reflete no aumentodo esforço de pesca, na preferência por práticas individuais, no uso de apetrechos considerados predatóriose na pesca em regiões e períodos proibidos, levando ao declínio da atividade. As característicasparticulares do arrastão de praia, de ser uma pesca coletiva, que desenvolve laços e valores sociaisimportantes para o espírito comunitário, como coletividade, colaboração, respeito às normas sociais,reunião e partilha, precisam ser incorporadas à agenda de preocupações dos órgãos gestores. Para tanto,é necessária a participação dos usuários no processo de gestão, o que também permitiria considerardevidamente a história dessa prática e a projeção de cenários que os pescadores mais velhos conseguemfazer, baseados em suas experiências e nas profundas mudanças socioambientais pelas quais passaram. A incorporação da dimensão simbólica ou não material de apropriação do recurso é, neste sentido, umacondição necessária à gestão sustentável da atividade.

Este relato avalia e apresenta alternativas para o atual modelo de controle e apropriação social dos manguezais da Baía de Paranaguá, com sugestões para o seu zoneamento e a eventual adoção de estratégias de gestão patrimonial. A sugestão básica é a de que a gestão dos manguezais regionais não deve ser confundida com conservação estrita, como sugerido pela legislação ambiental. New ways of managing brazilian mangroves: the Paranaguá Bay study case Abstract This report assesses and presents alternatives to the current control and social appropriation model of Paranaguá Bays mangroves, including zoning suggestions and the eventual adoption of ownership management strategies. The basic suggestion is that the management of the regional mangroves should not be mistaken with strict conservation, as suggested by environmental legislation.

A diversidade biológica vem deixando de ser tratada como conceito ecológico estrito nos últimos anos e assumindo as características de um verdadeiro recurso global, graças aos avanços da biologia molecular e da engenharia genética. Apesar disto, nao existem ainda boas estimativas da biodiversidade nem mesmo como grandeza taxonômica. Um caso particularmente evidente deste desconhecimento generalizado é dado pela própria biodiversidade marinha. Cerca de 200 mil espécies de plantas e animais marinhos sãoatualmente conhecidas, mas há estimativas, mais ou menos fundamentadas, de que a diversidade potencial possa variar de 500 mil a 5 milhoes de espécies. Este artigo tem por objetivo avaliar criticamente o conceito de biodiversidade, com ênfase no caso particular da biodiversidade marinha, juntamente com uma análise da atual disponibilidade de recursos humanos e materiais para o seu simples levantamento, .taxononuco.

Este artigo apresenta uma síntese do atual conhecimento das marismas da Baía de Paranaguá, procurandoacentuar suas diferenças fisiográficas, fiorísticas e faunísticas em relaçao aos manguezais locais. Os usose formas de apropriação desses sistemas têm sido pouco estudados na região e seus recursos potenciaise suas funções ecológicas têm sido subestimados. Uma análise comparativa dos atributos estruturais efuncionais dos manguezais e marismas regionais acentua a necessidade de revisão da legislação ambientalespecífica.

DOI: 10.7147/GEO3.1120

Este artigo apresenta e discute o referencial conceitual de propostas voltadas para a formação e pesquisa na área do desenvolvimento e meio ambiente. São analisadas com maior detalhe as noções de desenvolvimento sustentável e de interdisciplinaridade, por constarem de todas as formas de expressão da demanda social ambientalista e da maioria dos cursos em Desenvolvimento e Meio Ambiente. Diversos programas de pós-graduação ou pesquisa de caráter interdisciplinar vêm sendo recentemente implantados no Brasil, tentando incorporar esta dualidade conceitual da sustentabilidade e da interdisciplinaridade às suas práticas e reflexões. Esta nova realidade acadêmica, surgida com a criação de cursos interdisciplinares, exige o desenvolvimento de formas de avaliação muito distintas daquelas até então usadas para a análise de programas de cunho disciplinar. O trabalho propõe formas de acompanhamento e avaliação de desempenho, mais coerentes e compatíveis com as estruturas e modos de funcionamento originados destes novos conceitos. Abstract We present and discuss the conceptual framework of research and formation in the realm of environmental and developmental issues. The widely used concepts of sustainable development and interdisciplinarity are critically analyzed. Many graduate programs, recently created in Brazil, have tried to incorporate both concepts to their planning and practice. To evaluate such interdisciplinary programs we need new procedures, which may widely differ from the current institutional model, originally planned for disciplinary courses. We propose alternate forms of evaluating the performance of such graduate programs which are more adequate and compatible with the newly created academic structures.

Petroleum biomarkers (hopanes, terpanes and steranes) are frequently assessed in estuarine sediments as tracers of oil input. In order to compare distinct patterns of hydrocarbon accumulation in mudflats, salt marsh and mangrove, sediments from two transects (control and impacted areas) were sampled in Paranaguá Bay, SW Atlantic. Concentrations of n -alkanes, polycyclic aromatic hydrocarbons (PAHs) and petroleum biomarkers (hopanes, terpanes and steranes) were determined, as well as bulk parameters (TOC, grain size and δ13C). N -alkanes concentrations were similar between control and impacted sites (respectively, 3.03 ± 1.20 μg g−1 and 4.11 ± 3.02 μg g−1) and reflected a high biogenic input. Conversely, PAHs and petroleum biomarker concentrations were three to six times higher in impacted site than the control site (respectively, 60.4 ± 23.3 ng g−1 and 22.0 ± 25.0 ng g−1 for PAHs and 197.7 ± 51.8 ng g−1 and 40.2 ± 32. ng g−1 for hopanes). Despite these differences, concentrations were lower than those reported for highly impacted areas worldwide. Diagnostic ratios and hydrocarbon parameters (e.g. total PAHs and total petroleum biomarkers) helped to distinguish human impact in the ecological zones, suggesting different sources and/or levels of weathering, confirmed by ANOVA tests. TOC played a fundamental role to the concentration of hydrocarbons, showing similar distributions along the transects. Petroleum biomarkers could clearly indicate the preferential sites of deposition and assign different levels of anthropic contamination by hydrocarbons, thus providing clear information about the chronic petroleum pollution in coastal sediments. Image 1 • Hydrocarbons assessed in mudflat, salt marsh and mangrove of a subtropical estuary. • Hydrocarbon levels varied in correlation to organic carbon and fine sediments. • PAHs and petroleum biomarkers in the impacted site were higher (3–6 fold). • N -alkanes reflected biogenic hydrocarbon input in control and impacted sites. • Petroleum biomarkers evidenced HCs contamination under a high biogenic background. Petroleum hydrocarbons are reliable molecular markers to assess low-level hydrocarbon contamination in salt marshes and mangroves, along the terrestrial-aquatic gradient. [ABSTRACT FROM AUTHOR]

Abstract Estuaries are unique coastal ecosystems that sustain and provide essential ecological services for mankind. Estuarine ecosystems include a variety of habitats with their own sediment-fauna dynamics, all of them globally undergoing alteration or threatened by human activities. Mangrove forests, saltmarshes, tidal flats and other confined estuarine systems are under increasing stress due to human activities leading to habitat and species loss. Combined changes in estuarine hydromorphology and in climate pose severe threats to estuarine ecosystems on a global scale. The ReBentos network is the first integrated attempt in Brazil to monitor estuarine changes in the long term to detect and assess the effects of global warming. This paper is an initial effort of ReBentos to review current knowledge on benthic estuarine ecology in Brazil. We herein present and synthesize all published work on Brazilian estuaries that has focused on the description of benthic communities and related ecological processes. We then use current data on Brazilian estuaries and present recommendations for future studies to address climate change effects, suggesting trends for possible future research and stressing the need for long-term datasets and international partnerships.

Intensive exploitation and transport of oil and derivatives are increasing the risk of coastal contamination by either dramatic disasters or diffuse sources. Tools for monitoring diffuse contamination, such as diesel oil that leaks from marine vessels are much needed. We experimentally tested the efficiency of antioxidant biomarkers as indicators of chronic exposure to diesel oil in a mudflat from the subtropical Bay of Paranaguá, in southern Brazil. We examined the effects of three successive diesel oil spills, with two weeks of recovery time between exposures, on the edible clam Anomalocardia flexuosa . Previous studies have highlighted its potential as a bioindicator species for diesel oil contamination in subtropical and tropical ecosystems. Endpoints measured in gill and digestive gland homogenates included the activity of antioxidant enzymes SOD, GPx, GST and levels of lipid peroxides. PAHs concentration in sediments and soft tissue were also quantified. GST and SOD were the most responsive biomarkers to the exposure. There were significant but non–cumulative departures from control levels in organisms from treated samples, which were, in all cases, more common 48 h after each experimental spill. Biomarker responses were more evident in the digestive gland than in gills. This work validated the short–term responsiveness of biomarkers as measures of repeated pulsed in situ exposure to low concentrations of diesel oil. For their routine implementation into monitoring programs for tropical estuaries our general recommendations are 1) to include several reference sites, 2) to analyze biomarker data using a logarithmic–scale and 3) to interpret deviations from “normal” activity as multiplicative interval differences. [ABSTRACT FROM AUTHOR]

Offshore petroleum exploration has increased the risks of oil spills in coastal tropical and subtropical habitats. Monitoring tools are needed to assess and protect environmental health. We determined baseline values of antioxidant biomarkers (CAT, SOD, GPx, GST, MDA) for five ecologically relevant species in a subtropical system in southern Brazil. Regional baseline levels are compared with literature data as a basis to eventually test their efficacy as post-spill monitoring tools. Differences in the antioxidant response among species, contamination, and seasons were tested using univariate and multivariate analyses. The bivalves Anomalocardia flexuosa and Crassostrea rhizophorae and the catfish Genidens genidens emerge as suitable sentinel species. Seasonality is the main factor accounting for biomarkers variability, and not background contamination level. However, interactions between season and contamination level are also significant, indicating that biomarkers respond to complex environmental settings, a fact that needs to be fully understood for designing proper monitoring programs. [ABSTRACT FROM AUTHOR]

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Highlights: [•] We evaluate the ecological status of four benthic sites in the port. [•] We use biological and chemical indicators located along a presumed environmental gradient. [•] High disturbance is reflected by low diversity and high AMBI values in inner sites. [•] Coprostanol seemed to derive from sea lions rather than from sewage outfalls. [ABSTRACT FROM AUTHOR]

We determined values of antioxidant biomarkers catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione S-transferase (GST) and malondialdehyde (MDA) in two bivalve species from a subtropical system in Brazil. Differences in the biomarkers activities measured in digestive glands and gills sampled at two seasons and in sites with different levels of contamination were tested using univariate and multivariate analyses. Seasonality was the main factor accounting for overall variability. Significant SOD and GPx activities and increased levels of lipid peroxides were detected in summer, while CAT activity was higher in winter. However, biomarkers respond to complex environmental settings as indicated by the significant interaction between season and contamination level. We propose A. flexuosa as a candidate for monitoring studies with sampling occurring at a yearly timescale, and using C. rhizophorae is better suited for designs that include both seasons. • Baseline levels for antioxidant enzymes are provided fortwotropical and subtropical bivalve species. • Seasonal and spatial variation in the biomarker response wasdescribed in bivalves'gills and digestive glands. • Multivariate approaches, such as redundancy analysis (RDA), are suggested for multi-species and multi-biomarker studies. • The multivariate antioxidant response was species-specific and strongly affected by seasonality. • A. flexuosa is an appropriate candidate for monitoring studies with sampling occurring at a yearly timescale. • C. rhizophorae is better suited for designs that include both seasons. [ABSTRACT FROM AUTHOR]

Marine plastic debris provides a significant surface area for potential colonization by planktonic and benthic harmful microalgae and for the adsorption of their toxins. Furthermore, floating plastics may substantially expand the substrate area available for benthic algae in the ocean, intensifying the transfer of potent toxins through pelagic food webs. In this study, we quantify the available surface area of micro- and macroplastics in different oceanic regions and assess the potential role of floating plastics as vectors for the transfer of toxins from three widespread benthic dinoflagellates, Gambierdiscus spp., Ostreopsis cf. ovata and Prorocentrum lima. To avoid bias associated to the occurrence of benthic algae in deep waters, we selected only records from 0 to 100 m depths. We estimate that 26.8 × 10 10 cm 2 of plastic surface area is potentially available in surface waters of the global ocean, mostly in the size range of large microplastics (1.01-4.75 mm). Based on the distribution of floating plastics and the habitat suitability of the selected microalgal species, the plastic relative colonization risks will be greater in the Mediterranean Sea and in the subtropical and temperate western margins of the oceans, such as the North American and Asian eastern coasts and, to a lesser extent, southern Brazil and Australia. In places where the colonization of O. cf. ovata cells on floating plastic debris has been properly quantified, such as the Mediterranean and southern Brazil, we estimate a colonization potential of up to 2 × 10 6 cells km -2 of ocean surface during the regular occurrence period and up to 1.7 × 10 8 cells km -2 during massive blooms of this species. As plastic pollution and harmful benthic algal blooms have both increased substantially over the past decades, we suggest that their interactive effects can become a major and novel threat to marine ecosystems and human health., Competing Interests: Declaration of competing interest The authors declare no conflicts of interest., (Copyright © 2022 Elsevier B.V. All rights reserved.)

We evaluated the accumulation of okadaic acid (OA), a diarrhetic toxin, and the antioxidant responses in the marine annelid Laeonereis acuta exposed to the benthic toxigenic dinoflagellate Prorocentrum cf. lima. Nontoxic Tetraselmis sp. was used as a control diet. Living cells of the two algae were supplied as food to animals kept in agar medium for 72 h. To assess the significance of the observed effects, our experimental design treated the algal species (diet), algal cell densities, and exposure time as fixed factors. Responses of the organisms were assessed through oxidative stress biomarkers (glutathione-S-transferase [GST], catalase [CAT], reduced glutathione [GSH] and lipid peroxidation [LPO]). Toxin accumulation was measured by LC-MS/MS in whole-body homogenates after 12, 24 and 72 h of exposure. Worms exposed to the toxigenic dinoflagellate gradually accumulated OA, with toxin levels directly related to the cell density of Prorocentrum cf. lima. Worms fed with Prorocentrum cf. lima exhibited decreased CAT activity, increased LPO levels - both interactively affected by algal species and time - and decreased GSH levels, which were interactively affected by algal species and cell density. Higher LPO levels, along with the inhibition of CAT and GSH, clearly indicated an oxidative stress situation in worms exposed to the toxigenic dinoflagellate. Laeonereis acuta accumulated moderate OA levels and may act as a vector of OA to food webs in estuarine areas under high Prorocentrum cf. lima abundance., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Mangrove forests are highly productive and play a major role in global carbon cycling. Their carbon accumulation can be influenced through the consumption of nutrient-poor leaves and propagules by herbivore crabs. Anthropogenic nutrient input from sewage contamination is widespread in these often naturally nutrient-limited ecosystems. We hypothesised that sewage-mediated nutrient input to mangrove stands of Paranaguá Bay (southern Brazil), would alter the nutrient sources available for crabs, e.g. through microphytobenthos increase, and that this would reflect in their feeding behaviour. We predicted that propagules of Rhizophora mangle in contaminated stands would experience lower grazing pressure from their two main local consumers (Ucides cordatus and Goniopsis cruentata). We compared herbivory rates on R. mangle propagules in sewage contaminated and uncontaminated mangrove stands. We found that herbivory rates were significantly lower in contaminated than uncontaminated forests, but this pattern could not be clearly attributed to increased nutrient availability., (Copyright © 2016 Elsevier Ltd. All rights reserved.)