Degradação Ambiental das Zonas Litorais

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BUBBLE-NET : system to catch fish and the respective method of use

Fishing is a socio-economic activity of great relevance worldwide. However the environmental sustainability of the fishing gears is far from being effective. It is necessary to find more selective types of fishing to ensure sustainable catches of target species and also to protect other organisms accidentally caught with no commercial value. The answer to these problems arises, often, from the nature itself, as in the case of bubble net feeding, the feeding behavior of the humpback whale (Megaptera novaengliae). These whales trap the school of fish surrounding them with a wall of bubbles they send by the blowhole (Leighton et al, 2004) (Johson et al, 1984), (fig. 1). Thus, we are developing a device that mimics the whale behavior. This device presents large environmental benefits such as the reduction of bycatch, the absence of ghost fishing, clean capture, that is the absence of human handling, and sustainable yield by allowing the capture of the legal quantities and sizes. There are also economic advantages, such as the reduction of fishing gear, increased device lifetime and reduction of maintenance cost associated

In-vitro setting and multiplication of Pulicaria microcephala, an endemic species from Berlengas Island

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Ecotourism based on the observation of sea turtles: a sustainable solution for the touristic promotion of São Tomé and Príncipe

Wildlife-based ecotourism has been stated as an efficient tool to promote the conservation of endangered species and habitats. These activities also aim to create economic revenue for local communities. Likewise, ecotourism, intends to involve these communities in the management of the conservation programs and develop educational activities, either for children, locals, or tourists, in order to increase awareness about target species and habitats. This study addressed the recent ecotourism activities in the observation of sea turtles which are being developed in São Tomé and Príncipe. These charismatic marine reptiles are vulnerable or endangered due to human activities, such as meat and egg consumption, illegal trade, habitat loss, climatic change, pollution and fisheries bycatch. Therefore, ecotourism using flagship species, like sea turtle, establishes a sustainable alternative to destructive activities, promoting the country’s environmental, economic and social development, the three pillars of sustainability. In this context, the objective of this study is to know the potential of São Tomé and Príncipe as a turtle watching-based ecotourism destination. An exploratory analysis was carried out through two questionnaires (one focused to the Morro Peixe’s local community and another to the tourists that were engaged in turtle watching activities), in order to know the perception of the inhabitants and tourists regarding the programs and initiatives for the conservation of sea turtles. Despite the awareness that already exists among inhabitants regarding the conservation of sea turtles, the results showed that they do not straightforwardly accept the prohibition for the capture of sea turtles, but most of the population of Morro de Peixe is receptive to changes in the community regarding their protection. In fact, the population is beginning to recognize that tourism, due to the protection given to these endangered species, may become (in the medium term) a sustainable source of income. Regarding tourists’ profile, these are mostly Portuguese, with a high level of education and income. They are well informed about the need for sea turtle conservation and seek to carry out tourism activities that pursue this protection. In fact, this also demonstrates the potential the country has as a turtle watching-based ecotourism destination.info:eu-repo/semantics/publishedVersio

Conserving Endemic Plant Species in Oceanic Island’s Protected Areas

Oceanic islands are known for their high levels of plant diversity, due to disjunct geographical distribution that leads to speciation. The main factors contributing to genetic speciation includes the creation of a barrier within a previously widely distributed taxon and the limited dispersal of seeds, which favours genetic differentiation and, thus, fosters rapid speciation. Plant survival and population fitness vary according to environmental factors and to human interference. This chapter depicts the importance of oceanic islands as biodiversity hotspots, discusses the threats to which endemic plants on islands are exposed, namely climate change, invasive alien species, urbanisation, touristic activities, fire, changes in agriculture practices and collecting pressure. The best practices worldwide to protect endemic plant species in protected areas are also addressed, namely the implementation of prevention and mitigation actions, the programs executed to protect endemic species, and management plans to avoid future threats

Environmental limits of low salinity to Gracilaria gracilis development. Where do we draw the line?

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Protecção ambiental e informação financeira : os impactos, os riscos e a sua divulgação em direcção a um desenvolvimento sustentável

Com a presente comunicação, os autores pretendem sintetizar os principais danos ambientais provocados pela acção do homem, de forma isolada ou através das unidades económicas, evidenciando a responsabilização dos agentes e os programas da União Europeia (UE) quanto às questões ambientais

In vitro evaluation of the antibacterial and antioxidant activities of extracts of Gracilaria gracilis with a view into its potential use as an additive in fish feed

Fish in aquaculture systems are subject to several stressors that inhibit the immune response and potentiate the development of disease and increased mortality. The inclusion of additives in the fish diet, namely seaweeds or their extracts, that are natural sources of bioactive compounds can be an important tool for promoting the health and well-being of these animals. The present study aims at the development of sustainable and effective methodologies for the extraction of bioactive compounds of the red seaweed Gracilaria gracilis, exploring its antibacterial and antioxidant potential and considering its potential use as an additive for functional fish feeds. The yield of the extraction methods was evaluated upon the use of sequential solid–liquid extraction techniques with ethanol and water as solvents, different extraction temperatures (room temperature: 40ºC and 70ºC), and extraction time. The results demonstrated that the adoption extraction times of 30 min. at 40ºC provided higher yields. We also evaluated the antioxidant capacity and the antibacterial properties of the obtained extracts against different strains that cause fish diseases by disk diffusion and broth microdilution methods. The antioxidant activity was determined by the DPPH reducing capacity method and quantification of total polyphenols content (TPC).With these results, we can establish extraction procedures that allow the future use of G. gracilis extracts, with antibacterial and antioxidant effects in a safe and effective way.info:eu-repo/semantics/publishedVersio

New insights on the sporulation, germination, and nutritional profile of Gracilaria gracilis (Rhodophyta) grown under controlled conditions

The red seaweed Gracilaria gracilis is a widely cultivated species known for its high agar content. It is also an important source of proteins, minerals, and vitamins. The chemical profile of seaweed depends on the cultivation methods used and the growing conditions to which they are exposed. Thus, two independent methods of sporulation and germination were tested upon Gracilaria gracilis grown in controlled conditions. During the tests, different substrates, culture media and incubation times were tested to induce cystocarp maturation. The results showed that cystocarp maturation and spore release were successful, with a visible volume increase and format change in the protruding cystocarps. Furthermore, the process of maturation to germination was accomplished, fulfilling the complete life cycle. In parallel, the nutritional profile of the biomass obtained was evaluated and compared with the nutritional values of biomass collected from the environment. Results showed no significant differences between wild specimens and cultivated ones in organic matter, ash content, lipid content, carbohydrates, or phycocolloid content. The present work, therefore, presents two simple alternative methods with potential applications in start-ups aimed at the cultivation of seaweed. Through these methods, it is possible to obtain biomass with nutritional characteristics similar to those obtained in the wild.info:eu-repo/semantics/publishedVersio

Effects of different drying conditions on the rehydration ratio and water holding capacity properties in three different species of algae Ulva lactuca, Codium vermilara and Codium tomentosum

Over the last years, algae have been increasingly used in Human food due their rich chemical and nutritional composition, particularly the high supply of essential nutrients to the human body such as protein and dietary fiber. Dietary fiber can be divided into two different types: soluble and insoluble. The characteristics of soluble dietary fiber are related to some physical and chemical properties such as rehydration ratio and water holding capacity and are important in assigning the functional and organoleptic properties and in preventing some human pathologies such as cardiovascular disease and obesity. The present study aimed to investigate the influence of different drying conditions on the rehydration ratio and water holding capacity of three green algae, Codium vermilara, Codium tomentosum and Ulva lactuca. The methods used for the determination of water retention capacity and rehydration ratio were similar to those used in previous studies (Susuki, T. et al., 1996). The algae were processed in a tray dryer and the drying conditions were: Temperature: 30ºC and 40ºC; Relative Humidity: 28%47% ; air velocity 1,9 m/s. In this work, it was concluded that higher drying temperature conditions originate lower rehydration ratio and consequent lower water holding capacity possibly due to a higher physical damage in the algae tissues. It was also observed that both Codium species have higher values for these two parameters than Ulva lactuca, under the same rehydration conditions