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- Zooplankton distribution in a marine protected area: The Berlengas Natural Reserve, Western Coast of PortugalPublication . Mendes, Susana; Marques, Sónia Cotrim; Azeiteiro, Ulisses Miranda; Fernández-Gómez, Mª José; Galindo-Villardón, Mª Purificación; Maranhão, Paulo; Morgado, Fernando; Leandro, Sérgio MiguelZooplankton distribution in the Berlengas Natural Reserve (Portugal) was studied over a period of one year (February 2006 to February 2007). Monthly sampling was performed at 6 stations, differentiated according to depth and distance to the coastline. The aim of this study was to investigate the overall zooplankton variability through its different dimensions (space vs. time). The Partial Triadic Analysis (PTA) was used to study the spatial variability of the zooplankton community and its dynamics in time and the dynamic trajectories of the zooplankton species for each site. It was possible to distinguish a neritic-ocean gradient of the zooplankton composition and a temporal variability. Four distinct periods can be highlighted considering the distribution of the dates and the arrangement of the species: (i) the first one comprised August to November, (ii) the second one was related to June and July, (iii) the third one associated with spring (April and May) and, (iv) the latest one was related to winter (February, March and December 2006 and January and February 2007). The PTA method showed the similarities between the successive data tables and proved to be useful for investigating biotic structures and detecting spatial-temporal patterns in zooplankton distribution.
- Using biomarkers to address the impacts of pollution on limpets ( Patella depressa ) and their mechanisms to cope with stressPublication . Silva, Cátia S. E.; Novais, Sara C.; Simões, Tiago; Caramalho, Márcia; Gravato, Carlos; Rodrigues, Maria J.; Maranhão, Paulo; Lemos, Marco F. L.Contaminant discharges, derived from human activities, are major concerns as they exert a continuous ecological pressure on aquatic systems, causing in fact cascading community effects. Although with associated ecological and fitness costs, physiological and biochemical defense mechanisms may restore the organism’s internal balance. Several studies have pointed biomarkers as tools to assess contamination levels, and also to understand potential mechanisms to cope with stress. In the present study, the fitness costs of limpets Patella depressa located in two different contaminated sites and when transplanted into a different common environment – with no known historical contamination – were assessed through the measurement of oxidative stress, energy metabolism responses, and fatty acid profile changes. Integrated biomarker response index (IBR) revealed differences in responses between organisms of the different origin sites, with greater antioxidant and detoxification activities in the site with the higher contamination life-history (higher IBR index). Moreover, different abilities of this species to deal with the new environmental condition were also observed. After the transplant, and despite the differences in the initial profiles, response patterns became similar between both populations (similar IBR index), with organisms from the less contaminated site suffering a higher impact with a demarked increase in their detoxification and antioxidant defenses, as well as higher changes on fatty acid abundance/composition. Through an integrated biomarker profile analysis in a transplant context, this work provides a distinct insight on the mechanisms of response and tolerance to environmental stress, and fitness costs of this potential sentinel marine species in the context of environmental contamination changes.
- Maintenance of two-spotted goby, Gobiusculus flavescens (Fabricius, 1779) (Perciformes, Gobiidae), in captivity as a resource for ornamental fishkeepingPublication . Teles, Vera; Silva, Ana; Mendes, Susana; Maranhão, PauloThe survival and growth of semipelagic two-spotted goby (Gobiusculus flavescens) were investigated in the laboratory to appreciate the ability of this species to be kept in captivity as a resource for ornamental fishkeeping. The survival of individuals was tested under three temperatures (23°C, 25°C and 27°C) during 12 days. The growth of individuals was tested using two diets: Diet 1-“SERA ®vipan” + “SERA® discus granulat” and Diet 2-“Mysis and Artemia brine shrimp” (Ocean Nutrition®), at 21°C, during 5 weeks. The low death rate at 23°C (10%) can indicate some potential for this species to be used in ornamental aquariophilia. The diet consisting of Mysis sp. and Artemia sp. brine shrimp (Diet 2) appears to be well accepted be the fishes and promotes a good growth. The two-spotted goby proved to be a species very easy to handle and to maintain at the appropriate temperatures.
- Praias rochosas do litoral de Peniche: Livro de CampoPublication . Rodrigues, Inês; Mouga, Teresa; Maranhão, Paulo; Leandro, SérgioPeniche é uma cidade do litoral português, sendo a cidade mais ocidental da Europa continental, conhecida pelas excelentes condições para a prática do surf e do turismo de sol e mar. A cidade encontra-se implantada numa península, que em tempos foi uma ilha, repleta de escarpas rochosas e extensas praias arenosas, tanto a sul como a norte. Exibe um vasto património natural e paisagístico, fruto da grande diversidade geomorfológica que constitui a costa: dunas, arribas e recifes rochosos são alguns habitats marinhos característicos. De entre estes, as estruturas rochosas (falésias, afloramentos rochosos, plataformas, entre outros) exibem uma biodiversidade notável, sendo ideais para a observação de organismos marinhos, próprios das zonas litorais.
- Do mar para o prato: biologia, ilustração e gastronomiaPublication . Leandro, Sérgio Miguel; Maranhão, Paulo; Barraca, Catarina; Correia, Catarina; Borges, Patrícia; Alexandre, António; Salgado, PedroPara as comunidades dependentes da pesca, a gastronomia de mar assume especial relevo para o seu desenvolvimento económico, contribuindo para a promoção e atratividade do seu território e consequente garante de muitos postos de trabalho. Do mar ao prato - biologia, ilustração e gastronomia integra para cada recurso a biologia/ecologia, o perfil nutricional, a gastronomia tradicional e a gastronomia moderna, salteada com a arte da ilustração cientifica.
- Peixes das Berlengas: Manual ilustrado da ictiofauna das BerlengasPublication . Costa, Telma; Mouga, Teresa; Maranhão, Paulo; Leandro, SérgioEste guia ilustrado, muito acessível mesmo para o leigo, apresenta, depois de uma nota introdutória sobre as Berlengas, um conjunto de informação de base simples e bem estruturada, que nos permite entender facilmente as principais características de cada grupo, seguindo-se, de forma concisa, a morfologia e a distribuição geográfica de cada espécie.
- The microalga Dunaliella and its applications: a reviewPublication . Barbosa, Miguel; Inácio, Leonardo Garcia; Afonso, Clélia; Maranhão, Pauloand industry. The high adaptability of Dunaliella to high salinity, as well as its fast growth and production of several metabolites have triggered interest. The attention of industry relates to its ability to synthesize several high-value compounds, such as β-carotene, lipids, glycerol, vitamins, and proteins. In addition, due to its tolerance to high salinity, contamination is reduced, and it can grow in open systems. Dunaliella salina can accumulate up to 25% dry weight in lipids and is the most efficient natural source of β-carotene. This review highlights the general characteristics of the genus, associated with its history, morphology, reproduction, occurrence, and taxonomy. The metabolic pathways for carotenoid and lipid synthesis are described. Relevant information on the most common strains is provided as well as the most widely used growth systems and conditions, and the expression systems under development. Applications of Dunaliella in several areas of the industry are also highlighted. Thus, this review can serve as a basis for future work and for the development of environmentally friendly, simple, and highly cost-effective production methods.
- Ecological features of a rocky intertidal community exposed to sewage effluentPublication . Conde, Anxo; Pacheco, Joana; Marques, Sónia Cotrim; Afonso, André S.; Leandro, Sérgio; Maranhão, PauloSewage is among the largest components of coastal pollution, showing a variable scale and size when causing an impact. In this study, temporal and spatial sewage-related gradients were identified using univariate and multivariate methods. Phosphates and nitrogen-based nutrients, except nitrate, were associated to sewage. Abundance and species richness decrease with distance from the sewage outfall while evenness increased. Filterfeeder bivalves and grazer crustaceans showed preference for the sewage discharge site. Gastropods were more abundant at an intermediate distance, likely reflecting primary production enhancement by sewage. Beta diversity was lower at the location and time with highest sewage loadings. The turnover component of beta diversity expressed as an absolute or proportional value was also useful to detect temporal and spatial sewagerelated gradients. Highly energetic hydrodynamics contributes to ameliorate sewage impacts, yet not enough to veil the effect of pollution in this study.
- Binomial transformation applied to presence-absence community dataPublication . Conde, Anxo; Leandro, Sérgio; Maranhão, Paulo; Domínguez, JorgeCommunity data is often transformed or standardized to meet the requirements and assumptions of multivariate analysis. While these methods are usually appropriate for abundance data, they are seldom applied to presence absence data. Here, a method of transforming a binary matrix using the binomial probability is described. Number of trials (n), number of successes (x) and probability of success (p) are necessary to compute the binomial probability. Successes were defined as the number of sites where the species occurrence can be considered; trials were equal and greater than the number of successes. The actual occurrence of each species along the gradient was considered the probability of success. The Mantel statistic associated with the binomially transformed distance matrix and the distance matrix based on binary data were used to choose an appropriate binomial transformation. The chosen binomial transformation gave greater value to species indicating habitat typologies. Binomially transformed data rendered results closer to expectations.
- Desenvolvimento de Paté de lapa, Patella spp. com adição de medronho, Arbutus unedoPublication . Ganhão, R.; Rodrigues, S.; Maranhão, P.Limpets Patella are gastropods molluscs with an increasing use in human food, being a popular food too much appreciated in several coastal regions of Portugal. According to the chain of seafood, the consumption of fishery products rich in polyunsaturated fatty acids, has replaced the products of terrestrial animals through the filleted products, restructured products and precooked products. Food oxidation is the most important cause in the deterioration of nutritional and sensory quality of fish products. So, in recent years, there has been an increasing utilization of natural antioxidants of vegetable origin (fruits and vegetables) in substitution of the synthetic antioxidants in the preparation of restructured products of animal origin (burgers, sausages and pâtés). In addition to this antioxidant effect, there is a beneficial relationship between the consumption of fruit and vegetable rich in phenolic compounds in the prevention of certain diseases. So, this project intends to produce and characterize physical-chemical properties, sensorial analysis and microbiological analysis in one pâté elaborate with limpets and with addition of arbutus wild fruit, as well as valorisation of these raw materials to providing the nutritional/functional and economic value to the development of an innovative product (pâté). Furthermore, we evaluated the oxidative stability of pâté in refrigeration for 90 days and its acceptability. Thus, we produced three types of innovative pâtés: I) Patella spp. pâté with BHT (PCON), II) Patella spp. pâté with 3% of the Arbutus unedo (PAU3) and III) Patella spp. pâté with 6% of the Arbutus unedo (PAU6). The results of the evaluation of oxidative stability (PAU6>PAU3>PCON) confirm the high performance of the Arbutus unedo extract rich in phenolic compounds as effective inhibitor in lipid oxidation of the Patella spp. pâté and with good sensory acceptability.