Percorrer por autor "Rangel, Mafalda"
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- Análise custo viagem de roteiros subaquáticos (de Apneia) na Praia da Marinha (Algarve)Publication . Rangel, Mafalda; Dentinho, T. P.; Araújo, G.; Lopes, J.; Gonçalves, J. M. S.; Erzini, KarimPretendeu-se definir o valor da utilização recreativa de mergulho em apneia, em três roteiros implementados na Praia da Marinha, Algarve. Utilizou-se o método do custo de viagem para definir o valor de uso e os benefícios de recursos naturais utilizados para esta actividade de recreação. Validaram-se 115 inquéritos efectuados entre 15/07 a 15/9 de 2008, analisando-se os dados pelo modelo de regressão. Considerou-se como variável independente o número de mergulhos efectuados e como variável dependente os diversos custos, considerando o tempo dispendido na actividade ponderado por uma fracção do rendimento declarado. Concluiu-se que o excedente médio por mergulho é de 5,0 €, pelo que o valor de uso dos roteiros é de 600 €/ano, correspondente a um total de 30000 € admitindo uma taxa de desconto de 2% e a manutenção do recurso por muitos anos. Com uma capacidade de carga de 1.000 mergulhos por ano, a renda total do recurso por ano passa a ser de 5000 € e o valor económico total de 250000 €.
- Assessing the land-and seascape determinants of recreational diving: evidence for Portugal’s south coastPublication . Cardoso-Andrade, Mariana; Cruz-Jesus, Frederico; Rego, Francisco Castro; Rangel, Mafalda; Queiroga, HenriqueScuba diving is one of the most popular coastal recreational activities, and one of the few that are allowed in multiple-use marine protected areas. Nevertheless, like many other coastal activities, if in excess, it may harm coastal ecosystems and their sustainable use. This paper focuses on the seascape and landscape characteristics that are most associated with the existence of dive sites, aiming to identify other suitable locations along the coast to potentially reduce environmental pressure (e.g., overcrowding and physical damage) on the existing dive sites. Logistic regressions were employed to model the suitability for dive sites existence in the Portuguese south coast (Algarve), one of the most popular Summer destinations in mainland Europe. Results suggest that closeness to waterlines and piers and the presence of rock structures in the coastal strip are the most important attributes that positively influence dive sites’ existence, whereas the beach environment and the presence of muddy sediments are negatively associated with it. In this study, we suggest the application of a logistic model to find alternatives for the explored dive sites as a quick and easily applied coastal management tool. Moreover, we find it useful for the implementation of coastal conservation strategies extended to other coastal activities.
- Co-design of a marine protected area zoning and the lessons learned from itPublication . e Costa, Horta; Guimarães, M. Helena; Rangel, Mafalda; Ressurreição, Adriana; Monteiro, Pedro; Oliveira, Frederico; Bentes, Luis; Sales Henriques, Nuno; Sousa, Inês; Alexandre, Sofia; Pontes, João; Afonso, Carlos; Belackova, Adela; Marçalo, Ana; Cardoso-Andrade, Mariana; Correia, António José; Lobo, Vanda; Gonçalves, Emanuel J.; Pitta e Cunha, Tiago; Gonçalves, Jorge Manuel SantosMarine Protected Areas (MPAs) are a tool to safeguard marine natural systems, yet their effectiveness depends on how well they are integrated into the existing socioeconomic context. Stakeholder engagement in MPA design can contribute to increasing integration. This study focuses on the co-design of an MPA between researchers, public administration, the private sector, and non-governmental organizations. The proposed MPA is in Portugal and includes an area that is a hotspot for biodiversity and economic activities. This is the first MPA proposal in mainland Portugal co-designed using a participatory approach. This study highlights the steps of the zoning process and synthesizes the eight main lessons learned, useful for other cases, particularly for relatively small coastal MPAs with multiple socioeconomic activities. Three zoning proposals were developed and discussed within the participatory process. The proposals considered the best scientific and local knowledge available and were defined using ecological, socioeconomic, and shape-area guiding principles. In an iterative manner and following a participatory approach, compromises with stakeholders were achieved, and a final proposal, scientifically sound and socially accepted by most stakeholders, was delivered to the government. The final zoning plan will achieve ambitious conservation goals, including the largest fully protected area to be declared in mainland Portugal, while minimizing the impacts on the existing economic activities and promoting its sustainability. This process resulted in valuable lessons that may be applied elsewhere and guide future MPA implementation or rezoning of existing ones. These transdisciplinary and participatory processes can be time and resource-consuming but are vital for ensuring MPA effectiveness.
- Comprehensive characterization of the Algarve octopus, octopus vulgaris: nutritional aspects and quality indexes of lipidsPublication . Cabado, Ana G.; Costas, Celina; Sousa, David Baptista de; Pontes, João; Rangel, MafaldaThe common octopus (Octopus vulgaris) supports one of the most valuable small-scale fisheries in Portugal, particularly in the Algarve region, with substantial socioeconomic implications. This species holds significant potential for human consumption due to its low lipid content, favorable fatty acid profile, high-quality protein, and essential microelements. This study aimed to provide a comprehensive characterization of octopus specimens landed in two key Algarve fishing areas-Barlavento/Windward (Alvor Harbour) and Sotavento/Leeward (Fuzeta Harbour). We assessed their nutritional value, focusing on protein quality, lipid indexes, trace minerals, and essential vitamins, as well as overall safety and quality. All regulated contaminants and additional potential risks were also evaluated, yielding fully satisfactory safety results. The research was conducted within the framework of the European Sea2See project, which aims to enhance consumer trust and acceptance of sustainably harvested or farmed seafood in Europe. Our findings demonstrate that Algarve octopus is a nutritionally rich seafood product, promoting cardiovascular health and general well-being.
- Developing self-guided scuba dive routes in the Algarve (Portugal) and analysing visitors' perceptionsPublication . Rangel, Mafalda; Pita, C. B.; Gonçalves, J. M. S.; Oliveira, F.; Costa, C.; Erzini, KarimScuba diving allows for underwater visitation of cultural and natural resources. Underwater routes can be used as a tool for guided and supervised underwater visits. Two scuba diving routes were implemented in the Algarve (South of Portugal), the "B24" and "Poco" diving sites. The perceptions of scuba divers regarding several aspects of the routes and the existing support infrastructures were studied following a survey carried out through face-to-face interviews from 2008 to 2012. Divers profile and their perceptions were analysed using 246 valid questionnaires. Divers were mainly Portuguese, over 30 years old and with more than 12 years of formal education. Some of the support infrastructures did not achieve a "good" or "acceptable" grade. This should be carefully considered by diving operators and managers, because perceptions tend to circulate throughout the diving tourists. All features of interpretative slates were graded as highly satisfactory. Overall, diver satisfaction increased slightly after route implementation, with an average ranking of "good". These findings support the implementation of underwater routes as a way to promote diving activity, and to increase divers' environmental education and awareness. (C) 2013 Elsevier Ltd. All rights reserved.
- Development of a responsive fisheries management system for the Portuguese crustacean bottom trawl fishery: Lessons learntPublication . Silva, C.; Mendes, H.; Rangel, Mafalda; Wise, L.; Erzini, Karim; Borges, M. D.; Ballesteros, M.; Santiago, Jose Luis; Campos, Aida; Vioarsson, J.; Nielsen, K. NA prototype for a Responsive Fisheries Management System (RFMS) was developed in the context of the European FP7 project EcoFishMan and tested on the Portuguese crustacean trawl fishery. Building on Results Based Management principles, RFMS involves the definition of specific and measurable objectives for a fishery by the relevant authorities but allows resource users the freedom to find ways to achieve the objectives and to provide adequate documentation. Taking into account the main goals of the new Common Fisheries Policy, such as sustainable utilization of the resources, end of discards and unwanted catches, a management plan for the Portuguese crustacean trawl fishery was developed in cooperation with the fishing industry, following the process and design laid out in the RFMS concept. The plan considers biological, social and economic goals and assigns a responsibility for increased data collection to the resource users. The performance of the plan with regard to selected indicators was evaluated through simulations. In this paper the process towards a RFMS is described and the lessons learnt from the interaction with stakeholders in the development of an alternative management plan are discussed. (C) 2014 Elsevier Ltd. All rights reserved.
- Do fisher associations really represent their members’ needs and opinions? The case study of the octopus fishery in the Algarve (south Portugal)Publication . Rangel, Mafalda; Pita, Cristina; de Oliveira, Manuela Maria; Guimarães, Maria Helena; Rainha, Rita; Sonderblohm, Carlos; Monteiro, Pedro; Oliveira, Frederico; Ballesteros, Marta; Gonçalves, Jorge Manuel Santos; Pierce, Graham J.; Erzini, KarimFishers’ participation in the fishery management decision-making process is generally low, particularly in small-scale fisheries (SSF). Within the overarching goal of improving fisheries governance, fishers’ participation is crucial. Yet, how can fishers participate in the decision-making processes which affect their actions, and to what extent do fisher associations represent their interests? These questions were tackled by means of an empirical case study in the “Tertúlia do Polvo” project, focusing on the octopus SSF in the Algarve region (south Portugal), where the octopus fishery is managed top-down with sporadic participation of fishers. During the study (2014 and 2015), seven participatory workshops (tertúlias) were held, involving fisher associations, management authorities and researchers, to propose and discuss management measures for the fishery. Also, a face-to-face questionnaire survey (121 valid replies) was undertaken with local fishers to gauge their opinions about the management measures proposed during the workshops. Results show a strong agreement between the outcomes achieved during the workshops and the main concerns and possible solutions identified by fishers. Taking into consideration the difficulty in structuring and assuring a transparent and effective participation of fishers in the management of their activity, the results obtained are promising. In this study, the use of a participatory process (restricted to a small group of stakeholders) combined with consultation (targeting a sample of the fisher population) allowed the validation of the overall results obtained. Such a methodological approach can be tried in other fishing communities to implement efficient and effective collaborative management, contributing to improved fisheries governance.
- Eco-touristic snorkelling routes at Marinha beach (Algarve): Environmental education and human impactsPublication . Rangel, Mafalda; Pita, C. B.; Gonçalves, J. M. S.; Oliveira, F.; Costa, C.; Erzini, KarimThe use of natural areas for underwater coastal marine activities such as snorkelling is growing, but the amount of ecological and socioeconomic data on these activities is scarce and relates mainly to coral reef areas. Three underwater self-guided routes were designed at Marinha Beach (Algarve, Portugal), based on scientific information, with in situ interpretation and guidance, as a way to enhance biodiversity awareness and, hence, reduce the probability of human impacts. The routes were implemented in two consecutive summer seasons and after each season, visual census techniques were used to describe flora composition and cover area (seaweeds and seagrasses) in order to understand patterns and evaluate human impacts. Snorkelers' opinions and perceptions about several issues related to the routes' environmental education role (e.g. role in enhancing biocliversity awareness) were investigated by questionnaire after the snorkelling activity. An inter-annual difference inflora assemblages was found, probably associated to natural variability, rather than snorkelers' impacts. Results indicate that, in fact, in situ education and interpretation can raise environmental awareness if properly addressed, resulting in a satisfactory way of engaging snorkelers in the protection and in the conservation of the visited environments, thereby preventing negative ecological impacts. (C) 2015 Elsevier Ltd. All rights reserved.
- Effects of different slipping methods on the mortality of sardine, Sardina pilchardus, after purse-seine capture off the Portuguese Southern coast (Algarve)Publication . Marçalo, Ana; Guerreiro, Pedro; Bentes, Luis; Rangel, Mafalda; Monteiro, Pedro; Oliveira, Frederico; Afonso, Carlos; Pousao-Ferreira, Pedro; Benoit, Hugues P.; Breen, Mike; Erzini, Karim; Gonçalves, Jorge Manuel SantosThe effects of two different slipping methods on the survival, physical and physiological response of sardines, Sardina pilchardus, captured in a purse-seine fishery were investigated in southern Portugal. Sardines were collected and transferred into holding tanks onboard a commercial fishing vessel after being captured, crowded and deliberately released using two slipping procedures: standard and modified. The standard slipping procedure aggregated fish at high densities and made them "roll over" the floatline, while the modified procedure aggregated the fish at moderate densities and enabled them to escape through an opening created by adding weights to the floatline. Both slipping methods were compared with minimally harmed non-slipped sardines (sardines collected from the loose pocket of the purse seine). Survival rates were monitored in captivity over 28 days using three replicates for each treatment. The estimated survival of sardines was 43.6% for the non-slipped fish, 44.7% for the modified slipping and 11.7% for the standard slipping treatments. Scale loss indicated the level of physical impact experienced, with dead fish from the non-slipped and modified slipping technique showing significantly lower scale loss than those fish from the standard slipping treatment within the same period. Of the physiological indicators of stress measured, cortisol, glucose, lactate and osmolality attained peak values during slipping and up to the first hours after introduction to captivity. This work indicates that although delayed mortality after release may be substantial, appropriately modified slipping techniques significantly enhance survival of slipped sardines.
- Engaging and legitimizing communities: co-designing a community-based marine protected areaPublication . Rangel, Mafalda; Horta e Costa, Barbara; Guimarães, Mª Helena; Ressurreição, Adriana; Monteiro, Pedro; Oliveira, Frederico; Bentes, Luis; Sales Henriques, Nuno; Sousa, Inês; Ferreira Alexandre, Teresa Sofia; Pontes, João; Afonso, Carlos; Belackova, Adela; Marçalo, Ana; Cardoso-Andrade, Mariana; Cortês, António; Correia, António José; Lobo, Vanda; Gonçalves, Emanuel J.; Cunha, Tiago Pitta e; Gonçalves, Jorge Manuel SantosMarine Protected Areas are increasingly used as tools to preserve marine habitats and biodiversity worldwide. Nonetheless, creating MPAs in densely populated multi-use coastal areas comes with intrinsic conflict potential, since protection and economic development are not always hand-in-hand and local users might disagree with the designation of such conservation tools. The use of inclusive and transparent participatory processes to co-design such MPAs can be seen as a way of protecting biodiversity while acknowledging the needs of local users and building conservation tools that fit both purposes. Here we describe a participatory process developed to codesign a Marine Protected Area of Community Interest in a biodiversity, fishing and tourism hotspot in the Algarve (southern Portugal) where the majority of involved stakeholders (96 %) endorsed the final MPA proposal. The methodology and tools used are described in detail, lessons learned are critically analysed and a roadmap to be used in other realities is provided. Evidences collected show that the approach developed allows conservation and economic activities to share the same ground and advocate for the same goals in preserving coastal marine habitats.
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