ESTM - Artigos em revistas internacionais
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Percorrer ESTM - Artigos em revistas internacionais por Domínios Científicos e Tecnológicos (FOS) "Ciências Naturais::Ciências da Terra e do Ambiente"
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- Destination Brand Experience: A Study Case in Touristic Context of the Peneda-Gerês National ParkPublication . Martins, Hugo; Carvalho, Paulo; Almeida, NunoBased on the scientific literature, this paper emphasises the destination brand experience (DBE) (multidimensional construct and second-order factor) in order to analyse the implications it plays regarding visitors’ satisfaction, their intentions to revisit and their intentions to recommend it. In terms of methodology, a confirmatory factor analysis was used to test the model and the research hypotheses. The sample was composed of 507 tourists who visited the Peneda-Gerês National Park in Northern Portugal. Results showed an acceptable fit. The items of each construct were very strong. Positive significant results were found for all the considered hypotheses, particularly regarding the association of sensory DBE and behavioural DBE (subdimensions of the DBE scale) with satisfaction. The sensory DBE and affective DBE subdimensions of the DBE scale were meaningfully associated with visitors’ intentions to recommend. Satisfaction was a strong mediator for sensory DBE impact on their intention to revisit and to recommend, and a less strong effect was found for satisfaction as a mediator for behavioural DBE impact on intentions to revisit and to recommend. The theoretical contribution of this study aimed to deepen the analysis of the DBE construct in its multidimensional aspect and its relationship with other constructs. The results are discussed in relation to their theoretical and practical relevance.
- Developmental Toxicity of Endocrine Disrupters Bisphenol A and Vinclozolin in a Terrestrial IsopodPublication . Lemos M.F.L.; van Gestel, C. A. M.; Soares, A. M. V. M.Studies of the effects of endocrine-disrupting compounds (EDCs) on invertebrates are still largely underrepresented. This work aims to fill this gap by assessing the effects of bisphenol A (BPA) and vinclozolin (Vz) on the terrestrial isopod Porcellio scaber (common rough woodlouse). Male adult and sexually undifferentiated juvenile woodlice were exposed to the toxicants. Effects on molting regime and growth were investigated independently for males and female woodlice after sexual differentiation. Both chemicals elicited developmental toxicity to P. scaber by causing overall decreased growth. Nevertheless, BPA induced molting, whereas Vz delayed it. Although the LC 50 values for juvenile and adult survival were fairly similar, juvenile woodlice showed an increased chronic sensitivity to both chemicals, and female woodlice were most the sensitive to BPA. We recommend the use of adults, juveniles, female, and male woodlice, as well as a large range of toxicant concentrations, to provide valuable information regarding differential dose responses, effects, and threshold values for EDCs.
- Extended producer responsibility: a differential fee model for promoting sustainable packagingPublication . Pires, Ana; Martinho, Graça; Rita Ribeiro; Mafalda Mota; Luís TeixeiraExtended producer responsibility in the European Union has been shown to be incapable of promoting environmentally friendly packaging, mainly because of the economic instrument used: the producer fee. To make the producer fee capable of both reflecting and influencing how packaging is produced, we propose a mathematical model for calculating a differential fee (the sustainable producer fee or SPF). The development of the model involves the following steps: the selection of sustainability criteria, the aggregation of criteria using multi-criteria decision making, the formulation of the SPF calculation, and the generation of a web-based interface for packers and product importers to calculate the differential fee applying to their own packaging.
- Feeding habits of Solea senegalensis in earthen ponds in Sado estuaryPublication . Castelo Branco, Maria Ana; Arruda, Marco A.; Gamito, SofiaThe senegale sole, Solea senegalensis Kaup, 1858, is a commercially valuable fish and it is beginning to be cultured in a semi-intensive way in fish farms in southern European countries. The present study was initiated to investigate the diet of S. senegalensis under semi-extensive conditions. The feeding habits of sole were studied in two earthen ponds of a fish farm in the Sado estuary. In one earthen pond, artificial fish ration was given. S. senegalensis feeds on few prey items, its diet is mainly composed of insect larvae (Chironomus salinarus) and polychaeta (Hediste diversicolor). The diet composition of this species suggests feeding specialization, by consuming mainly annelids and insect larvae and by avoiding other items, extremely abundant in the environment, such as gastropods. In the water reservoir where ration was given, some fish consumed simultaneously benthic organism together with ration. However, benthic organisms seem to be the most important component of S. senegalensis diet.
- Herbivory drives kelp recruits into ‘hiding’ in a warm ocean climatePublication . Franco, João N.; Wernberg, Thomas; Bertocci, Iacopo; Duarte, Pedro; Jacinto, David; Tuya, Fernando; Vasco Rodrigues, NunoAssessing effects of herbivory across broad gradients of varying ocean climate conditions and over small spatial scales is crucial for understanding its influence on primary producers. Effects of herbivory on the distribution and abundance of kelp recruits were examined experimentally at two regions under contrasting ocean climate. Specifically, the abundance and survivorship of kelp recruits and the abundance of macro-herbivores were compared between a 'cool' and a 'warm' region in northern and central Portugal, respectively. In each region, the abundance of kelp recruits and the intensity of grazing were compared between habitats of different topography within reefs (open reef vs. crevices). Compared to the 'warm' region, the abundance of kelp recruits was 3.9 times greater in the 'cool' region, where 85% of recruits were found in open reef habitats. In contrast, 87% of recruits in the 'warm' region were restricted to crevices. The 'warm' region had 140 times greater abundances of sea urchins, 45 times more herbi vorous fish and 4.1 times more grazing marks on kelp recruits than the 'cool' region. Grazing assays showed ca. 50 times higher rates of kelp biomass consumption, mainly by fishes, and zero survivorship of kelp recruits in the 'warm' relative to the 'cool' region. This study suggests both temperature and herbivores affect abundances of kelp recruits across latitudes, and demonstrates how herbivores affect their distribution at local scales, driving kelp recruits into 'hiding' in crevices under intense herbivory. Consequently, where net recruitment success is compromised by herbivory, the persistence of kelps will be contingent on availability of topographical refuges.
- Historical separation and present-day structure of common dolphinfish (Coryphaena hippurus) populations in the Atlantic Ocean and Mediterranean SeaPublication . Maggio, Teresa; Allegra, Alessandro; Andaloro, Franco; Barreiros, João Pedro; Battaglia, Pietro; Butler, Christopher M; Cuttitta, Angela; Fontes, Miguel Rodrigues Jorge; Freitas, Rui; Gatt, Mark; Karakulak, F Saadet; Macias, David; Nicosia, Aldo; Oxenford, Hazel A; Saber, Samar; Yildiz, Taner; Sinopoli, Mauro; Vasco Rodrigues, Nuno; Grant, W StewartThe common dolphinfish (Coryphaena hippurus) is an epipelagic, mid-trophic level, highly migratory species distributed throughout the world’s tropical and subtropical oceans in waters greater than 20C. Life-history variables, migratory behaviour, and genetic markers have been used to define major stocks in the central Atlantic Ocean and Mediterranean Sea. Here, we used the mitochondrial DNA gene NADH subunit 1 (688 bp) to test for differences between population groups. A total of 103 haplotypes were detected among 203 fish. Gene diversities in samples were large and similar among populations (mean h ¼ 0.932; range 0.894–0.987), but nucleotide diversities varied widely among samples (range p ¼ 0.004–0.034) and appear to reflect population histories. Principal component analysis revealed two large populations groups, and the analysis of molecular variation and pairwise values of UST resolved population structure within these groups. Populations in the eastern Atlantic and Mediterranean showed the largest amounts of divergence from one another (UCT ¼ 0.331). Adult movement and biophysical barriers to larval dispersal may explain contemporary differences between stocks, but the divergent populations in the Mediterranean Sea are likely due to isolations by cold temperature barriers during Pleistocene glaciations. The geographically large stock groupings require international cooperation in the harvest management and conservation of local dolphinfish population
- Mono-specific facies of Parazoanthus axinellae in Luiz Saldanha Marine ParkPublication . Gomes-Pereira, J.N.; Vasco-Rodrigues, N.; Afonso, A.; Albuquerque, M.; Berecibar, E.; Bernardes, L.; Calado, A.; Castanheira, A.; Tojeira, I.; Tempera, Fernando; Dias, F.C.; Santos, R.S.; Campos, A.S.We report the first mono-specific facies ofParazoanthus axinellaefrom the western Portuguese coast. The habitat was recorded using a MiniRov Observer on a large outcrop at ca. 55–60 m in the Luiz Saldanha Marine Park. A method to estimate the maximum uncertainty of the ROV position is illustrated and the occurrence of the facies is discussed.
- Phytoremediation of cadmium by the facultative halophyte plant Bolboschoenus maritimus (L.) Palla, at different salinitiesPublication . Santos, Márcia S. S.; Pedro, Carmen; Gonçalves, Sílvia; Ferreira, SusanaThe cadmium phytoremediation capacity of the halophyte plant Bolboschoenus maritimus (L.) Palla and the influence of water salinity were assessed in a greenhouse experiment, in order to better understand the bioremediation capacity of this plant. Three concentrations of cadmium (0, 50 and 100 μg l−1) and four salinity conditions (0, 5, 10 and 20) were chosen to evaluate the cadmium accumulation, in order to test these plants as a potential phytoremediation tool in brackish environments. The cadmium content in water and plants (underground organs, stems and leaves) was analysed with graphite furnace atomic absorption spectrometry. All the plants submitted to salinity 20 and in the three cadmium treatments died. The plants’ survival was highest in the lowest salinities, where highest growth and biomasses were also obtained. The plants presented more cadmium content in the rhizomes, followed by stems and even less in leaves. The salt stress of the plants interfered with their cadmium accumulation capacity. The highest cadmium accumulation in the rhizomes occurred at salinity 0, while the salinities 0 and 5 were the most adequate for stems and leaves. The experiment pointed out that B. maritimus represents a good possible intervenient for cadmium bioremediation in freshwater and low salinity brackish water environments, but its use is limited in the habitats of higher salinity. © 2015, Springer-Verlag Berlin Heidelberg.
- Planning forest recreation: environmental economic instruments and the public participationPublication . Oliveira, F.; Pintassilgo, P.; Mendes, I.; Silva, J. A.In Portugal there is a growing demand for natural areas that provide a wide range of outdoor recreation. This paper focuses on the particular case of the Mata Nacional de Leiria (Leiria National Forest). This is a pine tree forest with 11,000 hectares and eight centuries of history. It has always been a public forest with open access to everyone, a fact that contributes to different kinds of use and benefits (walking, cycling, picnics, collecting firewood, fruits and berries, and other recreation activities). The proximity to a major urban and industrial centre, on one hand, and to a very popular beach coast, on the other, makes this a resource that is widely used by both residents and visitors. In the future there is the possibility of implementing a set of actions to improve forest amenities and recreation, and later the emergence of environmental tourism activities and equipment. In this context, we want to know the economic valuation that actual users attach to these recreation improvements, but also realize their preferences and opinions regarding this project. For this purpose we designed, tested and applied a double bounded dichotomous choice contingent valuation questionnaire. The results presented in this paper focus on responses to attitudinal and follow-up questions. More than 70% of respondents have positively assessed the proposed improvements to the study area and about 40% enhanced their personal opinion on the type of interventions that they consider most appropriate. Answers focus the priority areas of intervention in the Mata Nacional de Leiria, the main concerns in its development, the type of actions that should (and should not) be implemented, respondents willingness to actively take part and, also, what the public authorities' role should be. At this stage, where Mata Nacional de Leiria is being considered in terms of future recreation and tourism offers, the results obtained provide important contributions and enhance the contingent valuation survey as a tool to support recreation planning, promoting public participation and the political decision-making process.
- Protein differential expression induced by endocrine disrupting compounds in a terrestrial isopodPublication . Lemos, Marco F. L.; Esteves, Ana Cristina; Samyn, Bart; Timperman, Isaak; van Beeumen, Jozef; Correia, António; van Gestel, Cornelis A. M.; Soares, Amadeu M. V. M.Endocrine disrupting compounds (EDCs) have been studied due to their impact on human health and increasing awareness of their impact on wildlife species. Studies concerning the organ-specific molecular effects of EDC in invertebrates are important to understand the mechanisms of action of this class of toxicants but are scarce in the literature. We have used a dose/response approach to unravel the protein expression in different organs of isopods exposed to bisphenol A (BPA) and vinclozolin (Vz) and assess their potential use as surrogate species. Male isopods were exposed to a range of Vz or of BPA concentrations. After animal dissection, proteins were extracted from gut, hepatopancreas and testes. Protein profiles were analysed by electrophoresis and differentially expressed proteins were identified by MALDI mass spectrometry. EDCs affected proteins involved in the energy metabolism (arginine kinase), proteins of the heat shock protein family (Hsp70 and GRP78) and most likely microtubule dynamics (tubulin). Different proteins expressed at different concentrations in different organs are indicative of the organ-specific effects of BPA and Vz. Additionally, several proteins were up-regulated at lower but not higher BPA or Vz concentrations, bringing new data to the non-monotonic response curve controversy. Furthermore, our findings suggest that some common responses to EDCs in both vertebrates and invertebrates may exist.
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