Browsing by Author "Cacabelos, Eva"
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- Do man-made habitats affect spatial patterns of mollusk abundance?Publication . Cacabelos, Eva; Martins, Gustavo M.; Sánchez, Rocío; Busquier, Laura; Mosquera, Rubén; Neto, Ana I.The fragmentation of natural habitats, together with its loss, is considered a major threat to biodiversity. Man-made habitats, e.g., seawalls and coastal defence structures, are a common feature causing the fragmentation on the shoreline of many urbanized coastal areas and will become more widespread in response to rising and stormier seas. Fragmentation can alter functional connectivity of habitats and determine the spatial distribution of organisms, since the movement and dispersal of individuals can be interrupted. However, ecological consequences of coastal defence structures have not been extensively studied and we know little about their effects in marine systems. One of the most important factors affecting the connectivity among fragments or patches is the ability of the organisms to disperse despite potential barriers. Spatial patterns of molluscs with planktonic larvae or direct development (non-planktotrophic larvae) has been compared before, but there is a growing interest to understand the role of the man-made habitats in determining the patterns of spatial abundances of marine organisms. This study was aimed at exploring the role of type of larval development (planktotrophic vs non-planktotrophic) on patterns of spatial variation of gastropods on rocky shores, elucidating the possible responsibility of habitat fragmentation in observed patterns (i.e. seawall presence). Strongly aggregated distribution patterns are supposed to be characteristic of organisms with direct development, while the existence of planktotrophic larvae could allow the homogeneous distribution of organisms with indirect development. We examined the distribution patterns of grazing molluscs with both planktotrophic (the gastropods Tectarius striatus and Melaraphe neritoides) and direct (e.g. Omalogyra atomus or Lasaea adansoni) development in continuous rocky shores, natural patches and fragments. Two natural rocky shores of each type (continuous rocky shores, natural patches and fragments), separated from each other by kms, were sampled. At the mid-intertidal level, the gastropods Tectarius striatus and Melaraphe neritoides were identified and quantified in situ in quadrats randomly deployed on the shore. Randomly replicates of seaweed turfs, composed mostly by articulated coralline algae, were collected in the chosen locations and target gastropods were sorted and quantified in the laboratory. We predict that organisms with planktotrophic development will be less affected by fragmentation because they have the ability to disperse among fragments.
- Dramatic changes in the structure of shallow-water marine benthic communities following the invasion by Rugulopteryx okamurae (Dictyotales, Ochrophyta) in Azores (NE Atlantic)Publication . Faria, João; Prestes, Afonso L.; Moreu, Ignacio; Cacabelos, Eva; Martins, Gustavo M.Biological invasions are considered one of the most important drivers of biodiversity loss. Here we use a before-after-control-impact (BACI) design to investigate the impact of Rugulopteryx okamurae on the structure of shallow-water marine benthic communities in São Miguel island, Azores. After its first appearance in 2019, R. okamurae has rapidly invaded much of the southern coast of the island, where it became the dominant algae. This was followed by significant changes in the structure of shallow-water marine benthic communities, with substantial losses of natural variability and species richness. Compared to before, there has been dramatic reductions in the abundances of articulated coralline algae, corticated algae and corticated foliose algae in invaded locations. These results highlight its highly invasive character, not seen with other, more well-known, invasive species. It remains to be investigated if its impacts persist throughout time and to quantify the functional consequences of such dramatic changes.
- Efeitos da urbanização nos ecossistemas costeirosPublication . Cacabelos, Eva[…]. Com o objetivo de analisar as implicações ecológicas resultantes da urbanização costeira e sugerir alternativas para minimizar alguns dos seus impactos, o grupo de Investigação Aquática Macaronésia (integrado no CIIMAR e composto por elementos do Departamento de Biologia da Universidade dos Açores) está a coordenar o projeto Estruturas urbanas: um fator de mudança na biodiversidade dos ecossistemas costeiros (http://www.bus-project.info/), financiado pela FCT e contando com a colaboração da Faculty of Science and Environment da Universidade de Plymouth. Este projeto, que teve inicio em Maio de 2013, está focado nos processos que influenciam as relações entre as espécies marinhas e o seu habitat. […].
- Factors limiting the establishment of canopy-forming algae on artificial structuresPublication . Cacabelos, Eva; Martins, Gustavo M.; Thompson, Richard C.; Prestes, Afonso L.; Azevedo, José M. N.; Neto, Ana I.Macroalgal canopies are important ecosystem engineers, contributing to coastal productivity and supporting a rich assemblage of associated flora and fauna. However, they are often absent from infrastructures such as coastal defences and there has been a worldwide decline in their distribution in urbanised coastal areas. The macroalga Fucus spiralis is the only high-shore canopy forming species present in the Azores. It is widely distributed in the archipelago but is never found on coastal infrastructures. Here we evaluate factors that may potentially limit its establishment on artificial structures. A number of observational and manipulative experiments were used to test the hypotheses that: (i) limited-dispersal ability limits the colonisation of new plants onto artificial structures, (ii) vertical substratum slope negatively influences the survivorship of recruits, and (iii) vertical substratum slope also negatively influences the survivorship and fitness of adults. Results showed that the limited dispersal from adult plants may be a more important factor than slope in limiting the species ability to colonise coastal infrastructures, since the vertical substratum slope does not affect its fitness or survivorship.
- Gastropods with different development modes respond differently to habitat fragmentationPublication . Cacabelos, Eva; Neto, Ana I.; Martins, Gustavo M.The role of the human-made structures in coastal ecosystems can determine the spatial distribution or patterns of spatial abundances of marine organisms. To contribute to the understanding of linkages between different components of habitats (i.e. natural and artificial structures), we explored the role of type of larval development (planktotrophic vs. non-planktotrophic) on patterns of spatial variation of gastropods on rocky shores, elucidating the possible responsibility of habitat fragmentation on their distribution. Obtained results suggest that habitat fragmentation affects differently the patterns of variability of species with different types of larval development. Namely, fragmentation caused by artificial structures mostly influence variability of species with non-planktotrophic development. Moreover, although abundance of the species with non-planktotrophic development varied at small spatial scales, suggesting that processes operating at this scale are likely the main drivers of their distribution, changes in species variability were not associated with differences in species abundance among habitats.
- Guia de boas práticas para a apanha de algas nos Açores : O projeto ASPAZOR e o caso-estudo de Asparagopsis spp.Publication . Faria, João; Navas Noguera, Daniel; Prestes, Afonso L.; Cacabelos, Eva; Moreu, Ignacio; Martins, Gustavo M.; Pereira, Leonel; Neto, Ana I.As macroalgas, sendo organismos fotossintéticos, são uma fonte de oxigénio e um recetor de dióxido de carbono. Elas fornecem habitat, refugio de predadores e um ambiente seguro para a desova e viveiro de muitas espécies. São ricas em minerais e vitaminas, proteínas, aminoácidos essenciais, ácidos gordos e fibras alimentares, e por isso usadas na alimentação humana. […]. A colheita manual deve ser favorecida à colheita mecânica. […].
- A guide for good harvesting practices of macroalgae in Azores (NE Atlantic) : The project ASPAZOR and the case study of Asparagopsis spp.Publication . Faria, João; Navas Noguera, Daniel; Prestes, Afonso L.; Cacabelos, Eva; Moreu, Ignacio; Martins, Gustavo M.; Pereira, Leonel; Neto, Ana I.Surely, most of the people at large have said or heard that seaweeds are only “plants of the sea”, which can be smelly when lying at the beach, without being aware of how important they are in the marine ecosystem (Mouritsen, 2013). Roughly, seaweeds, also known as macroalgae, are eukaryote, multicellular and macroscopic benthic algae, normally attached to firm substrata, mostly on rocky shores (Adams, 1994; Dawes, 1998; Rosas-Alquicira et al., 2012; Hurd et al., 2014). They are essentially found in the marine environment, although they may occur in brackish or even freshwater environments (Neto et al., 2005; Neto & Pinto, 2018). All seaweeds are algae, but not all algae are seaweeds, e.g. the microscopic algae, known as microalgae and/or phytoplankton (Mouritsen, 2013). Nevertheless, all seaweeds, at some point of their life cycle, are microscopic or unicellular, either as spores or as zygotes (Amsler & Searles, 1980; Lobban & Harrison, 1994). As with higher plants, they are oxygenic photosynthetic organisms, but here most algae cells contain the green pigment chlorophyll a that captures the needed sun’s energy for photosynthesis, the process of building energy-rich compounds (carbohydrates) from CO2 and the macro and micro nutrients available in the water (Mouritsen, 2013; Barsanti & Gualtieri, 2014; Neto & Pinto, 2018). Yet, they differ from plants in the determinant fact that they do not have true tissues, such as leaves, steams, roots or a transporting network, and neither produce flowers or seeds (Mouritsen, 2013; Neto & Pinto, 2018). Instead, they have an undifferentiated vegetative tissue called thallus, which is the plant body and may be simple or composed by a blade or frond (structure similar to a leaf) and a stipe or axis (similar to a stem). Some of them are attached to the substratum by a holdfast, whereas other use rhizoids or stolon-like structures (Neto et al., 2005). Moreover, seaweeds use simple reproductive structures to complete their life cycle by releasing gametes or spores into the environment (Barsanti & Gualtieri, 2014; Neto & Pinto, 2018). […].
- Impacte para o ecossistema e benefícios socioeconómicos da alga exótica Asparagopsis armata nos AçoresPublication . Cacabelos, Eva; Faria, João; Prestes, Afonso L.; Neto, Ana I.[…]. Desde novembro de 2016, o Subgrupo de Investigação em Ecologia Aquática Insular do Grupo de Biodiversidade dos Açores - Centro de Ecologia, Evolução e Alterações Ambientais (GBA/cE3c), com base na Universidade dos Açores, esta a desenvolver o projeto intitulado “Impacte ecossistemático e benefícios socioeconómicos de Asparagopsis armata nos Açores” (ASPAZOR, AÇORES-01-0145-FEDER-00060), financiado em 85% pelo FEDER e 15% pela ORAA, e aprovado pela Autoridade de Gestão do Programa Operacional AZORES 2020. A alga exótica A. armata e considerada como uma das espécies com maior potencial invasor nas aguas europeias, onde foi observada pela primeira vez em 1925, encontrando-se agora bem estabelecida na RAA. Aqui proliferam as duas fases do seu ciclo de vida, a fase produtora de gametas conhecida por A. armata e a fase produtora de esporos, anteriormente considerada como uma espécie distinta, Falkenbergia rufolanosa. Uma particularidade importante dos espécimes do género Asparagopsis e a produção de uma variedade de metabolitos com reconhecidas atividades antibacteriana, antimicrobiana, citotóxica e antioxidante, com aplicação em piscicultura, cosmética, e mesmo em medicina como alternativa a antibióticos convencionais. […].
- Limited effects of marine protected areas on the distribution of invasive species, despite positive effects on diversity in shallow-water marine communitiesPublication . Cacabelos, Eva; Martins, Gustavo M.; Faria, Joao; Prestes, Afonso L.; Costa, Tarso; Moreu Badia, Ignacio; Neto, Ana I.Marine protected areas (MPAs) can be an effective tool for the conservation and management of marine coastal habitats. MPAs have been shown to halt habitat degradation, enhance the biomass of exploited species and diversity in general. Yet, we still know little about its role in halting the spread of non-native species. In this study, we assessed the role of MPAs in the structure of shallow subtidal communities around Sao Miguel Island, in general, and particularly on distribution of the two species of genus Asparagopsis: A. armata and A. taxiformis. In the Azores, the former is a well-established invasive species, whereas the status of A. taxiformis is still questionable. Overall, there was a significant greater diversity in terms of both species richness and number of macroalgal functional groups within MPAs. However, when considering the relative abundance of the various macroalgal functional groups, or the assemblage as a whole (multivariate analysis), there was no significant difference between areas within and outside MPAs. The cover of A. taxiformis was significantly greater within MPAs but not its biomass, whereas no significant variation was observed for A. armata. Overall, results suggest that surveyed MPAs had a positive effect on the diversity of shallow-water macroalgal communities. However, they have a limited role on the distribution of both Asparagopsis spp. and negligible effects when considering the relative abundances of macroalgal functional groups.
- Marine algal flora of Santa Maria Island, AzoresPublication . Neto, Ana I.; Parente, Manuela I.; Cacabelos, Eva; Costa, Ana C.; Botelho, Andrea Z.; Ballesteros, Enric; Monteiro, Sandra; Resendes, Roberto; Afonso, Pedro; Prestes, Afonso L.; Patarra, Rita F.; Álvaro, Nuno V.; Milla-Figueras, David; Neto, Raul M. A.; Azevedo, José M. N.; Moreu, IgnacioBACKGROUND: The algal flora of the Island of Santa Maria (eastern group of the Azores archipelago) has attracted interest of researchers on past occasions (Drouët 1866, Agardh 1870, Trelease 1897, Schmidt 1931, Ardré et al. 1974, Fralick and Hehre 1990, Neto et al. 1991, Morton and Britton 2000, Amen et al. 2005, Wallenstein and Neto 2006, Tittley et al. 2009, Wallenstein et al. 2009a, Wallenstein et al. 2010, Botelho et al. 2010, Torres et al. 2010, León-Cisneros et al. 2011, Martins et al. 2014, Micael et al. 2014, Rebelo et al. 2014, Ávila et al. 2015, Ávila et al. 2016, Machín-Sánchez et al. 2016, Uchman et al. 2016, Johnson et al. 2017, Parente et al. 2018). Nevertheless, the Island macroalgal flora is not well-known as published information reflects limited collections obtained in short-term visits by scientists. To overcome this, a thorough investigation, encompassing collections and presence data recording, was undertaken at both the littoral and sublittoral levels down to a depth of approximately 40 m, covering an area of approximately 64 km2. The resultant taxonomic records are listed in the present paper which also provides information on species ecology and occurrence around the Island, improving, thereby, the knowledge of the Azorean macroalgal flora at both local and regional scales. NEW INFORMATION: A total of 2329 specimens (including some taxa identified only to genus level) belonging to 261 taxa of macroalgae are registered, comprising 152 Rhodophyta, 43 Chlorophyta and 66 Ochrophyta (Phaeophyceae). Of these, 174 were identified to species level (102 Rhodophyta, 29 Chlorophyta and 43 Ochrophyta), encompassing 52 new records for the Island (30 Rhodophyta, 9 Chlorophyta and 13 Ochrophyta), 2 Macaronesian endemics (Laurencia viridis Gil-Rodríguez & Haroun; and Millerella tinerfensis (Seoane-Camba) S.M.Boo & J.M.Rico), 10 introduced (the Rhodophyta Acrothamnion preissii (Sonder) E.M.Wollaston, Antithamnion hubbsii E.Y.Dawson, Asparagopsis armata Harvey, Bonnemaisonia hamifera Hariot, Melanothamnus harveyi (Bailey) Díaz-Tapia & Maggs, Scinaia acuta M.J.Wynne and Symphyocladia marchantioides (Harvey) Falkenberg; the Chlorophyta Codium fragile subsp. fragile (Suringar) Hariot; and the Ochrophyta Hydroclathrus tilesii (Endlicher) Santiañez & M.J.Wynne, and Papenfussiella kuromo (Yendo) Inagaki) and 18 species of uncertain status (11 Rhodophyta, 3 Chlorophyta and 4 Ochrophyta).