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- Potencial da Ilha de Porto Santo (Região Autónoma da Madeira) para a aquaculturaPublication . Almada, Emanuel José Faria; Maranhão, Paulo Jorge de SousaNos últimos 17 anos em Portugal houve um rápido aumento na produção e na Região Autónoma da Madeira (RAM) o cultivo tem vindo a ser explorado através de aquaculturas offshore, em jaulas costeiras. Devido ao crescimento deste sector, surge a necessidade de determinar novos locais de implementação de aquaculturas offshore. Esta necessidade exige uma avaliação de vários fatores: geográficos, meteorológicos, económicos e biológicos. Perante esta situação foi executado um estudo para avaliar a implementação da aquacultura offshore na Ilha de Porto Santo (IPS). Numa primeira fase foi efetuada uma análise de variáveis abióticas (correntes, ondas, marés vento e temperatura) na costa IPS, que permitiu a identificação de dois locais potencialmente viáveis, em relação à exposição destas variáveis. A situação de referência biológica foi determinada através de indicadores bióticos: avaliação da ictiofauna em 26 pontos da costa IPS, usando o método de transetos e a avaliação da macrofauna nos dois locais potencialmente viáveis, através de cores, recorrendo a mergulho com escafandro autónoma para recolha das amostras. A avaliação da macrofauna indicou uma baixa biodiversidade nos dois locais. Os registos da ictiofauna mostraram que as espécies Thalassoma pavo, Abudefduf luridus e Sparisoma cretense tiveram uma maior ocorrência, destacando as espécies S. cretense e Seriola sp., como as espécies mais abundantes com valor comercial e de consumo mais elevado. Posteriormente foi realizado um estudo socioeconómico através de duas metodologias: i) obtenção de orçamentos necessários para os transportes essenciais para o funcionamento de uma aquacultura e ii) questionários Delphi realizados à população local, restauração e governantes de modo a entender a opinião em relação à implementação em questão. Este estudo mostra que a Ilha do Porto Santo tem condições para a implementação de uma aquacultura offshore de forma viável, económica e ambiental.
- On the properties evolution of eco-material dedicated to manufacturing artificial reef via 3D printing: Long-term interactions of cementitious materials in the marine environmentPublication . Boukhelf, Fouad; Sebaibi, Nassim; Boutouil, Mohamed; Yoris-Nobile, Adrian I.; Blanco-Fernandez, Elena; Castro-Fresno, Daniel; Real-Gutierrez, Carlos; Herbert, Roger J.H.; Greenhill, Sam; Reis, Bianca; Franco, João N.; Borges, Maria Teresa; Pinto, Isabel Sousa; van der Linden, Pieter; Babé Gómez, Oscar; Meyer, Hugo Sainz; Almada, Emanuel; Stafford, Richard; Danet, Valentin; Lobo-Arteaga, Jorge; Tuaty Guerra, Miriam; Hall, Alice E.This paper deals with the evolution monitoring of biomass colonization and mechanical properties of 3D printed eco-materials/mortars immersed in the sea. Measurements of tensile strength, compressive strength, and Young’s modulus were determined on samples deployed along the Atlantic coast of Europe, in France, United Kingdom, Spain, and Portugal. The samples were manufactured using 3D printing, where six mix designs with a low environmental impact binder were used. These mortars were based on geopolymer and cementitious binders (Cement CEM III), in which sand is replaced by three types of recycled sand, including glass, seashell, and limestone by 30%, 50%, and 100% respectively. The colonization of concrete samples by micro/macro-organisms and their durability were also evaluated after 1, 3, 6, 12, and 24 months of immersion. The results showed that both biomass colonization and mechanical properties were better with CEM III compared to geopolymer-based compositions. Therefore, the mixed design optimized according to mechanical properties show that the use of CEM III should be preferred over these geopolymer binders in 3D printed concrete for artificial reef applications.
- A new signal of tropicalization in the Northeast Atlantic: the spread of the spotfin burrfish Chilomycterus reticulatus in Madeira Archipelago and its invasion riskPublication . Castro, Nuno; Schäfer, Susanne; Parretti, Paola; Monteiro, João Gama; Gizzi, Francesca; Chebaane, Sahar; Almada, Emanuel; Henriques, Filipe; Freitas, Mafalda; Vasco-Rodrigues, Nuno; Silva, Rodrigo; Radeta, Marko; Freitas, Rúben; Canning-Clode, JoãoCurrent trends in the global climate facilitate the displacement of numerous marine species from their native distribution ranges to higher latitudes when facing warming conditions. In this work, we analyzed occurrences of a circumtropical reef fish, the spotfin burrfish, Chilomycterus reticulatus (Linnaeus, 1958), in the Madeira Archipelago (NE Atlantic) between 1898 and 2021. In addition to available data sources, we performed an online survey to assess the distribution and presence of this species in the Madeira Archipelago, along with other relevant information, such as size class and year of the first sighting. In total, 28 valid participants responded to the online survey, georeferencing 119 C. reticulatus sightings and confirming its presence in all archipelago islands. The invasiveness of the species was screened using the Aquatic Species Invasiveness Screening Kit. Five assessments rated the fish as being of medium risk of establishing a local population and becoming invasive. Current temperature trends might have facilitated multiple sightings of this thermophilic species in the Madeira Archipelago. The present study indicates an increase in C. reticulatus sightings in the region. This underlines the need for updated comprehensive information on species diversity and distribution to support informed management and decisions. The spread of yet another thermophilic species in Madeiran waters provides further evidence of an ongoing tropicalization, emphasizing the need for monitoring programs and the potential of citizen science in complementing such programs.
- Artificial reefs in the North-East Atlantic area: Present situation, knowledge gaps and future perspectivesPublication . Reis, Bianca; van der Linden, Pieter; Pinto, Isabel Sousa; Almada, Emanuel; Borges, Maria Teresa; Hall, Alice E.; Stafford, Rick; Herbert, Roger J.H.; Lobo-Arteaga, Jorge; Gaudêncio, Maria José; Tuaty Guerra, Miriam; Ly, Océane; Georges, Valentin; Audo, Mariane; Sebaibi, Nassim; Boutouil, Mohamed; Blanco-Fernandez, Elena; Franco, Joao N.Artificial reefs have been deployed in multiple regions of the world for different purposes including habitat restoration and protection, biodiversity and fish stock enhancement, fisheries management and recreation. Artificial reefs can be a valuable tool for ecosystem protection and rehabilitation, helping mitigate the effects of anthropogenic impacts that we face today. However, knowledge on artificial reefs is unevenly distributed worldwide, with some regions having much more quality information available and published (e.g. European Mediterranean Sea area), while others, for instance the North-East Atlantic area, do not. Here, we provide a characterization of purposely built artificial reefs in North-East Atlantic area based on all available literature (i.e. research papers and reports), highlighting the needs and gaps that are vital for establishing future perspectives for artificial reef deployment and research. In the North-East Atlantic area, sixty-one purposely built artificial reefs have been deployed since 1970, mostly between the years 1990–2009, with Spain being the country with the highest number of artificial reefs. The most reported purpose for their deployment is fisheries productivity and habitat/species protection, although, most artificial reefs are multipurpose in order to maximise the benefits of a given financial investment. The majority of artificial reefs were submerged at < 50 m, mainly between 10 and 20 m of depth. The most used designs were cubic blocks and complex designs made by an array of combined shapes, which mostly consist of concrete (79%). From all the analysed data on artificial reefs, 67% of the cases reported surveys to assess biodiversity after the deployment. However, in 26% of those cases, data was not available. When data was available, only 31% of cases reported long-term biomonitoring surveys (3 years or more). Based upon these findings, we noticed a general lack of scientifically robust data, including records of species and abundance of both fish and invertebrates, as well as macroalgae, preventing an adequate determination of the best balance between shape, construction material and bio-colonization. Critiques and suggestions are discussed in the light of currently available data in order to perform more efficient research, evaluation and functioning of future artificial reefs.