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- Physiological potential of the chlorophyte Caulerpa prolifera for proliferation across the Mediterranean-Atlantic basins in a warmer oceanPublication . Olivé, Irene; E, Varela-Álvarez; Silva, João; Serrao, Ester; Santos, RuiOcean warming is altering the metabolic balances of organisms, favouring the expansion of thermo-tolerant individuals. The fast-growing macroalga Caulerpa prolifera is rapidly expanding in the Ria Formosa lagoon (Portugal), a connection area between Mediterranean and Atlantic basins. We investigated the metabolic capacity of C. prolifera to cope with ocean warming, to elucidate its expansion potential. The photosynthetic and respiratory plasticity of 4 populations of C. prolifera spread along the Mediterranean−Atlantic basins was assessed under a temperature range of 20 to 30°C. In addition, molecular markers were used to investigate the genetic identity of the strain found in Ria Formosa, which confirmed its Mediterranean origin. All examined populations showed large physiological thermo tolerance and metabolic plasticity to warming. The photosynthetic efficiency of C. prolifera improved by 50% with temperature, and the maximum photosynthetic production doubled along the temperature range tested. Respiration did not vary with temperature, whereas the metabolic quotient increased by more than 70%when temperature increased from 20 to 25−30°C. Minor differences in the photosynthetic descriptors were detected among populations, reflecting light- and dark-adapted physiology of Mediterranean and Atlantic populations, respectively. Our results show that all tested populations of C. prolifera have the physiological potential to cope with temperature increases up to 30°C, which indicates that ocean warming may contribute to the expansion of C. prolifera in the Mediterranean− Atlantic basins.
- Daily regulation of key metabolic pathways in two seagrasses under natural light conditionsPublication . Ruocco, Miriam; Barrote, Isabel; Hofman, Jan Dirk; Pes, Katia; Costa, Monya; Procaccini, Gabriele; Silva, João; Dattolo, EmanuelaThe circadian clock is an endogenous time-keeping mechanism that enables organisms to adapt to external environmental cycles. It produces rhythms of plant metabolism and physiology, and interacts with signaling pathways controlling daily and seasonal environmental responses through gene expression regulation. Downstream metabolic outputs, such as photosynthesis and sugar metabolism, besides being affected by the clock, can also contribute to the circadian timing itself. In marine plants, studies of circadian rhythms are still way behind in respect to terrestrial species, which strongly limits the understanding of how they coordinate their physiology and energetic metabolism with environmental signals at sea. Here, we provided a first description of daily timing of key core clock components and clock output pathways in two seagrass species, Cymodocea nodosa and Zostera marina (order Alismatales), cooccurring at the same geographic location, thus exposed to identical natural variations in photoperiod. Large differences were observed between species in the daily timing of accumulation of transcripts related to key metabolic pathways, such as photosynthesis and sucrose synthesis/transport, highlighting the importance of intrinsic biological, and likely ecological attributes of the species in determining the periodicity of functions. The two species exhibited a differential sensitivity to light-to-dark and dark-to-light transition times and could adopt different growth timing based on a differential strategy of resource allocation and mobilization throughout the day, possibly coordinated by the circadian clock. This behavior could potentially derive from divergent evolutionary adaptations of the species to their bio-geographical range of distributions.
- Causes and effects of wine tourism development in wineries: the perspective of institutional theoryPublication . Lavandoski, Joice; Pinto, Patrícia; Silva, João; Vargas-Sanchez, AlfonsoPurpose - This study aims to propose that the institutional environment exerts pressure on the behavior of wineries toward wine tourism development (WTD) and the effect of this influence confers legitimacy to the business of wine tourism.Design/methodology/approach - Structural equation modeling through partial least squares was applied to estimate and validate a model using data from a quantitative survey in the universe of 62 wineries with a wine tourism component along the Alentejo Wine Route in Portugal. The proposed model is based on institutional theory through an inter-organizational perspective of wineries.Findings - The results show that WTD coexists with a highly institutionalized environment, exerting distinctive mechanisms of external pressure together with the search for social legitimacy through actions and practices on the part of the involved wineries. However, the relationship between legitimacy and organizational performance in wineries with wine tourism is not validated.Research limitations/implications - The specific sample of the Alentejo wine companies does not allow the results to be generalized. Future studies should replicate the proposed research model using other geographic areas.Practical implications - The results are particularly interesting for managers of wineries and should be considered in the decision-making and strategic processes regarding wine tourism.Originality/value - The use of institutional theory in the wine tourism context is novel and original. This study fills a research gap by conducting an empirical investigation of wine tourism based on institutional theory, which allows the identification of exogenous factors that can influence and impose restrictions on the organizational behavior of winery companies toward wine tourism.
- Doutoramento Honoris Causa: Jafar JafariPublication . Águas, Paulo; Silva, João; Jafari, JafarO Professor Jafar Jafari é uma das mais fascinantes personalidades do nosso tempo no domínio dos Estudos Turísticos e é atualmente o mais respeitado académico a nível mundial, quer pelo mundo universitário, empresarial e por governos, quer por organizações mundiais, como a Organização Mundial do Turismo. Esta rara unanimidade é o resultado das suas excecionais qualidades humanas e profissionais, como professor de mérito, autor de artigos científicos de referência, editor associado a projetos de excelência, brilhante orador, consultor e construtor de redes para o estudo e transferência do conhecimento no Turismo.
- Tourists’ perceptions about the tourism in the Algarve: contributions for a sustainable tourism developmentPublication . Silva, João; Andraz, Jorge; Pereira, LN; Nunes, Rui Miguel da Cunha; Rijo, Ana RitaSince the construction of Faro Airport in 1965, the Algarve has developed into a mass tourism (Costa, 2005) and sun, sea and sand destination (Do Valle et al., 2012), becoming one of the most popular tourist destinations in Europe (Andraz & Rodrigues, 2016), and a crucial one for Portugal (Soler et al., 2019). The 5,412 square kilometre region has several features contributing to its atractiveness, such as mild weather conditions, over 3,000 hours of sunshine per annum and low rainfall (Visit Algarve, 2018). Natural areas occupy 70% of the 318 km Algarvian Coast and 37% of its territory consists of natural reservations, nature parks or protected landscape areas (Visit Algarve, 2018). The region hosts 31 of the 70 golf courses of Portugal and is a reputable golf destination, having received titles such as “Best Worldwide Golf Destination” by the International Association of Golf Tour Operator (IAGTO) on several occasions (Oliveira et al., 2019). The main source markets of the Algarve are domestic tourism and Europeans seeking a beach or golf holiday (Oliveira et al., 2019). With its high contribution to the GDP, the region strongly relies on tourism as a contributor to the economy (Do Valle et al., 2012).