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- Phytoplankton in two tropical mangroves of São Tomé Island (Gulf of Guinea): A contribution towards sustainable management strategiesPublication . C. Brito, Ana; Silva, Teresa; Beltrán, Carolina; Chainho, Paula; de Lima, Ricardo F.Phytoplankton are important primary producers in tropical coastal lagoons, with a critical role in sustaining food webs. However, most studies conducted in tropical systems with high anthropogenic influence have focused only on biomass. Water samples were collected, for phytoplankton (pigments and microscopy) and other environmental parameters, from two mangrove lagoons in São Tomé Island. The highest nutrient concentrations were observed in the mangrove of Praia das Conchas, indicating stronger nutrient inputs in this catchment area. Bottom oxygen deficiency was observed in the mangrove of Malanza, which is likely to be associated with the existence of a bridge that constrains the water exchange with the sea. Pigment analyses showed that overall chlorophyll a concentrations were low, indicating low phytoplankton biomass. The highest values were found at Praia das Conchas. It is suggested that chlorophyll a can be used as an indicator of anthropogenic pressure in this tropical system. Microscopy reveales the presence of Dinophysis sp. and Ostreopsis sp. cells, which can be harmful even at low densities. Water quality could be improved by enhancing oxygen condition in Malanza and by monitoring the occurrence of algal blooms, with potential benefits for public health and tourism.
- Projeto “Estado atual da ostra portuguesa (Crassostrea angulata) no estuário do Sado, ameaças e oportunidades para a sua exploração como recurso – CRASSOSADO”Publication . Cabral, Henrique; Costa, José Lino; Chainho, Paula; Marques, Filipa; Portela, Teresa; Ruano, Francisco; Angélico, Maria Manuel; Lourenço, Helena; Brás de Oliveira, Paulo; Bandarra, Narcisa; Grade, Ana; Freitas, Rosa; Chiesa, Stefania; Moreira, Anthony; Pires, Adília; Fernandes, Maria de Jesus; Falcão, Cristina; Silva, CarlosO projeto CRASSOSADO nasceu do desafio lançado pelo ICNF - RNES às instituições científicas portuguesas com trabalhos de investigação recentes sobre as populações portuguesas de ostra, nomeadamente o MARE/FCUL, a Universidade de Aveiro/CESAM e o IPMA, tendo sido solicitado que se identificassem e estudassem os aspetos mais prementes para assegurar a conservação e a exploração sustentada deste recurso no estuário do Sado, sendo o seu financiamento assegurado pelo Grupo Portucel Soporcel ao abrigo do Protocolo celebrado em 2014, entre o ICNF e a Portucel, S.A., no âmbito das medidas de compensação previstas na Declaração de Impacte Ambiental do projeto “Nova fábrica de papel nas instalações de Setúbal da Portucel, S.A.”. Seguidamente é feita uma breve súmula sobre a evolução recente das populações selvagens e a exploração de ostra no estuário do Sado e discutidos os assuntos considerados prioritários para cumprir o desiderato de assegurar a conservação e a exploração sustentada deste recurso no sistema em análise, e ainda enunciados os objetivos específicos estabelecidos para o atingir. A ostra-portuguesa, Crassostrea angulata (Lamark), teve uma elevada importância comercial na Europa até finais de 1970, altura em que praticamente desapareceu devido a elevadas mortalidades (FAO, 2007). A ostra do Pacífico, Crassostrea gigas (Thunberg), foi introduzida para substituir a ostra portuguesa e é atualmente a espécie com produção maioritária na Europa. Durante as décadas de 1960 e 1970 e devido, sobretudo, a um forte aumento da poluição industrial, urbana e agropecuária das áreas envolventes dos estuários do Tejo e Sado, ao aparecimento de patologias graves nas suas populações e, por fim, a uma sobre exploração dos bancos naturais, assistiu-se à extinção/desaparecimento da ostra portuguesa no estuário do Tejo e ao fim da sua produção comercial no estuário do Sado. Esta situação foi generalizada em toda a Europa, no entanto, algumas populações de C. angulata, localizadas sobretudo no Sul de Europa, resistiram à mortalidade massiva da década de 1970, bem como à introdução de C. gigas (Batista, 2007). O estuário do Sado é um bom exemplo desta situação, onde a presença da espécie passou a ser vestigial, resumindo-se a pequenos bancos na zona do canal daquele estuário, onde subsistiram escassos hectares de bancos naturais. Contudo, nos últimos quinze anos tem-se assistido a uma recuperação assinalável das antigas ostreiras do Sado, verificando-se a sua expansão para as zonas da baía. A melhoria significativa das condições ambientais do meio terá sido a causa próxima daquela recuperação. De facto, no estuário do Mira, sistema relativamente bem preservado em termos ambientais, onde sempre existiram populações naturais da espécie, sem contudo terem sido objeto de uma exploração comercial consistente, os fenómenos de declínio e extinção das populações de C. angulata nunca se verificaram. Ultimamente tem-se assistido a uma forte pressão no sentido de reforçar a introdução da ostra do Pacífico, C. gigas, sobretudo no estuário do Sado, mas também no estuário do Mira, à semelhança do que aconteceu noutras zonas da costa portuguesa, nomeadamente na Ria Formosa e na Ria de Aveiro. Apesar disso, o conhecimento de base necessário para a tomada de decisões sobre o licenciamento destas introduções é ainda deficitário, em particular no que diz respeito ao estado atual das populações de C. angulata e às condições que influenciam o sucesso do recrutamento. Foi nesta perspetiva que se decidiu focar o presente estudo na análise de alguns aspetos ecológicos, como a distribuição e a reprodução, de alguns constrangimentos importantes para estes organismos, nomeadamente a sua patologia e contaminação por metais, e ainda das caraterísticas genéticas nas populações presentes no sistema.
- Estudo sobre a Caraterização da Apanha de Isco nos Principais Sistemas Estuarinos Nacionais e Caraterização da Atividade de Importação de Isco Vivo, no âmbito do projeto PROMAR – “Isco Vivo: Anelídeos Poliquetas Como Isco Vivo Em Portugal: Gestão da Apanha, Importação e Cultivo”Publication . Costa, José Lino; Canning-Clode, João; Castro, João; Cancela Da Fonseca, Luís; Chainho, Paula; Fidalgo, Pedro; Sá, Erica; Alves, Ana Sofia; Castro, Nuno; Mirra, Carla; Cabral, SaraEste documento constitui o Relatório final relativo à prestação de serviços para elaboração de um estudo sobre a “Caraterização da Apanha de Isco nos Principais Sistemas Estuarinos Nacionais e Caraterização da Atividade de Importação de Isco Vivo”, no âmbito do projeto “ISCO VIVO: Anelídeos Poliquetas como Isco Vivo em Portugal: Gestão da Apanha, Importação e Cultivo”, financiado pelo Programa PROMAR, com o Instituto Politécnico de Leiria como instituição proponente. O presente relatório consiste na descrição dos trabalhos desenvolvidos entre novembro de 2014 e dezembro de 2015 para cumprir as tarefas previstas nesse estudo sobre a “Caraterização da Apanha de Isco nos Principais Sistemas Estuarinos Nacionais e Caraterização da Atividade de Importação de Isco Vivo”. Estas incluíam: a) Caraterização da apanha de isco nos principais sistemas estuarinos portugueses; b) Caraterização da atividade de importação de isco vivo em Portugal; c) Determinação do impacto potencial da importação de isco vivo no país. Apresentam-se no documento os principais resultados obtidos após a aplicação da metodologia prevista na proposta de trabalho, que incluiu a realização de amostragens (observações no terreno e realização de inquéritos) nos quatro principais sistemas estuarinos portugueses: Ria de Aveiro, estuário do Tejo, estuário do Sado e Ria Formosa.
- Assessing Ecosystem Services in Mangroves: Insights from São Tomé Island (Central Africa)Publication . Afonso, Filipa; Félix, Pedro M.; Chainho, Paula; Heumüller, Joshua; F. De Lima, Ricardo; Ribeiro, Filipe; Brito, Ana C.Mangroves are some of the most productive coastal systems on the planet and provide valuable ecosystem services (ES). They are especially important in threatened ecosystems and developing countries, where they are likely to have direct impacts on local communities. An approach based on ES allows assessing ecosystems across the domains of ecology, sociology and economy. This study focused on the evaluation of ES in mangroves and started by creating a comprehensive global list of mangrove ES based on the Millennium Ecosystem Assessment. These services were then quantified using the best available indicators for mangrove systems. The mangroves of Diogo Nunes, São João dos Angolares and Malanza, located in the São Tomé Island, were used to illustrate the challenges in applying ES indicators in this type of ecosystems. The obtained results confirmed that mangroves can provide important and diverse services. However, the high variability among mangrove systems affects their ability to deliver ES, requiring caution for the extrapolation across regions. This assessment emphasizes how the ES framework can be used as a tool to develop management plans that integrate conservation goals and human wellbeing.
- Age and growth of a highly successful invasive species: the Manila clam Ruditapes philippinarum (Adams & Reeve, 1850) in the Tagus Estuary (Portugal)Publication . Moura, Paula; Garaulet, Lucía; Vasconcelos, Paulo; Chainho, Paula; Costa, José Lino; Gaspar, MiguelThe Manila clam Ruditapes philippinarum (Adams & Reeve, 1850) was introduced in several regions worldwide where it is permanently established. In Portuguese waters, the colonisation of the Tagus Estuary by this invasive species coincided with a significant decrease in abundance of the native Ruditapes decussatus (Linnaeus, 1758). This study aimed to estimate the age and growth of the Manila clam, to compare the growth performance between R. philippinarum and R. decussatus in several locations worldwide, and to ascertain whether the Manila clam’s growth patterns contributed to the extensive distribution of this invasive bivalve in the Tagus Estuary. The growth of R. philippinarum in the Tagus Estuary was described through the von Bertalanffy equation SLt=65.2[1−e-0.34(t+0.93)], corresponding to a phi-prime index (φ’) of 3.160 and an overall growth performance of 4.974. This growth performance is the second highest recorded for R. philippinarum worldwide and was much higher than that of R. decussatus from Portugal. This study confirmed that the Tagus Estuary presents near-ideal environmental conditions for growth of the Manila clam. R. philippinarum displayed clearly invasive behaviour, spreading widely and growing faster than the native R. decussatus, which certainly contributed to the decline of its populations in the Tagus Estuary.
- Ecological aspects and potential impacts of the non-native hydromedusa Blackfordia virginica in a temperate estuaryPublication . Marques, Filipa; Angélico, Maria Manuel; Costa, José Lino; Teodósio, Maria Alexandra; Presado, Patrícia; Fernandes, António; Chainho, Paula; Domingos, IsabelThe hydrozoan Blackfordia virginica has been reported over a wide geographical area, although it is mainly restricted to scattered records within estuarine areas of temperate and tropical regions. The aim of this study was to understand the spatial and temporal variability of an established population of this non-indigenous species on a temperate estuarine ecosystem, and its impacts over the plankton community. Sampling was conducted from 2011 to 2013 in the Mira estuary (Portugal) and higher densities were observed during the summer of 2013, with a maximum of 1689.3 medusae.m−3. Spatially, higher abundances of medusae were associated with sites of higher abundance of oyster shells and higher percentage of hard substrate in the river bed. Smaller jellyfish were sampled in the vicinity of these hard substrate locations, suggesting these might be habitats for polyp fixation. A higher potential predation impact on the copepod population along the estuary was estimated for the summer of 2013, with a median half life of 6.1 days.
- On the Atlantic blue crab (Callinectes sapidus Rathbun 1896) in southern European coastal waters: Time to turn a threat into a resource?Publication . Mancinelli, Giorgio; Chainho, Paula; Cilenti, Lucrezia; Falco, Silvia; Kapiris, Kostas; Katselis, George; Ribeiro, FilipeThe blue crab Callinectes sapidus is native to the coastal waters of the western Atlantic Ocean, and along the US coasts the species supports an important fishery. The crab was introduced to Europe at the beginning of the 20th century. To date, the species is considered invasive and it has been extensively recorded in southern European waters (SEW), where it is starting to penetrate the shellfish market. Here, an integrated management strategy is proposed for the blue crab in SEW, including the Mediterranean and Black Sea and the eastern Atlantic coasts of the Iberian Peninsula. Taking as introductory examples two case studies represented by the red king crab Paralithodes camtschaticus and the green crab Carcinus maenas, a framework of key issues is reviewed, considering the double nature of the species as invaders and shellfish products. A SWOT analysis is eventually presented for C. sapidus, in order to perform a state-of-the-art synthesis of the proposed scenario, highlighting the potential opportunities as well as the weaknesses related with the limited knowledge of the ecological and economic impact of the species in invaded habitats. The review is concluded by an appraisal of the current trends in global and European crustacean fisheries. The ongoing expansion of C. sapidus might represent a useful management case study, where the need to control an invasive species and mitigate its ecological impact can be harmonized with the opportunity to value it as a fishery resource.
- Community perceptions about mangrove ecosystem services and threatsPublication . Afonso, Filipa; Félix, Pedro M.; Chainho, Paula; Heumüller, Joshua; F. De Lima, Ricardo; Ribeiro, Filipe; Brito, Ana C.The Ecosystem Service Framework discloses the ecosystem’s benefits to society and provides support to preserve threatened systems while considering the economic and social dimensions of the communities more dependent on its resources. Mangroves provide important and valuable goods and services to communities, at different spatial and temporal scales. Nevertheless, over-exploitation of these resources can generate poverty traps, where rural households can no longer use the ecosystem as a source of food security or income. This study uses three communities that live in surrounding areas of mangroves from São Tomé Island (Diogo Nunes, Angolares, and Malanza) as a case study. The main aim was to evaluate locals’ perspectives about ecosystem use, threats, and conservation. Questionnaires were conducted among local populations and provided valuable information to identify the major beneficiaries of mangrove resources. These results also indicated that the services and threats identified locally are different from those identified in the literature. The importance of considering the impact of local values and traditions in the use of ecosystem resources was also highlighted by the obtained results since São Tomé residents do not acknowledge the existence of services that do not bring a direct benefit. The absence of awareness about mangroves and their threats can cause severe damages to the ecosystem’s health, requiring the implementation of specific awareness-raising policies among populations that interact with mangrove ecosystems.
- Non-indigenous species in Portuguese coastal areas, coastal lagoons, estuaries and islandsPublication . Chainho, Paula; Fernandes, António; Amorim, Ana; Ávila, Sérgio P.; Canning-Clode, João; Castro, João J.; Costa, Ana C.; Costa, José Lino; Cruz, Teresa; Gollasch, Stephan; Grazziotin-Soares, Clarissa; Melo, Ricardo; Micael, Joana; Parente, Manuela I.; Semedo, Jorge; Silva, Teresa; Sobral, Dinah; Sousa, Mónica; Torres, Paulo; Veloso, Vera; Costa, Maria JoséTrends in abundance, temporal occurrence and spatial distribution of marine and brackish non-indigenous species (NIS) are part of the indicators to assess the compliance of Good Environmental Status in the European Marine Strategy Framework Directive (EU-MSFD). European-wide regional and national databases for NIS will be useful for the implementation of the EU-MSFD but there are still spatial gaps for some regions and taxonomic groups. In 2009, Portugal was among the countries with the lowest reported numbers of NIS in Europe and a national online database on NIS was not available. This study provides an updated list of NIS registered in Portuguese coastal and estuarine waters, including mainland Portugal and the Azores and Madeira archipelagos. A list of 133 NIS was cataloged, most of which recorded in the last three decades, showing that this area of the North Atlantic is no less prone to introductions than neighboring areas. Most NIS reported in the current inventory are native in the Indo-Pacific region. Fouling and ballast water are the most likely introduction vectors of NIS in the studied area but shipping routes connecting to the NIS native regions are rare, indicating that most species are secondary introductions. The high number of NIS in the Azores and Madeira islands indicates that this ecosystem type seems to be more susceptible to invasions but these preliminary results might be biased by a higher number of studies and knowledge on the NIS occurrence on the islands.
- Trade of live bait in Portugal and risks of introduction of non-indigenous species associated to importationPublication . Sá, Erica; Fidalgo E Costa, Pedro; Cancela Da Fonseca, Luís; Alves, Ana; Castro, Nuno; Cabral, Sara; Chainho, Paula; Canning Clode, João; Melo, Pedro; Pombo, Ana; Costa, José LinoDifferent invertebrate groups are often exploited on sediment shores and mudflats, including polychaetes, sipunculids, bivalves and crustaceans. The commercial importance of polychaetes and sipunculids, that has increased in the early 2000's because of its use as a food source for the aquaculture sector and a growing demand of worms for use as sea angling bait, seems to be declining nowadays. In Portugal bait harvesting from natural populations became insufficient to meet market demands and as a result, polychaetes and sipunculids have been imported in recent years. Due to this it was important to know the ways of the live bait import to Portugal, and to assess the risk of introduction of non-indigenous species associated to that live bait trade. The origin and quantities of imported live bait were determined by examining the landing's records at Lisbon airport, from two periods: 2002-2003 and 2012-2015. Live worms imported to Portugal arrived almost exclusively from China, USA and Vietnam. Monthly import data and bait registers at fish auction landings were significantly correlated, showing that bait captures and imports are directly related to higher bait demand. In addition, the risk of live bait's importation as an introduction vector for non-indigenous species was evaluated by examining the bait boxes content. Five worm species were identified in bait boxes with foreign species: Glycera dibranchiata, Namalycastis rhodochorde, Perinereis cultrifera, Perinereis linea, and Sipunculus (Sipunculus) nudus. The examination of bait boxes in Portugal suggested that there is a low risk of associated hitchhiker species introduction and dissemination, mostly because of packaging procedures, which should be advised. The same is not true to the non-indigenous live bait species.
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