ESTM - Artigos em revistas internacionais
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Browsing ESTM - Artigos em revistas internacionais by Field of Science and Technology (FOS) "Ciências Naturais::Ciências da Terra e do Ambiente"
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- 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.
- 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.
- Ridolfia segetum (L.) Moris (Apiaceae) from Portugal: A source of safe antioxidant and anti-inflammatory essential oilPublication . Cabral, C.; Poças Almeida, Juliana; Gonçalves, M.J.; Cavaleiro, C.; Cruz, M.T.; Salgueiro, L.Ridolfia segetum (L.) Moris essential oil was obtained by hydrodistillation and analysed by GC and GC-MS. The antioxidant properties were evaluated through the TBARS assay, and the in vitro anti-inflammatory activity was assessed through inhibition of NO production triggered by the Toll-like receptor 4 (TLR4) agonist, lipopolysaccharide (LPS), in mouse macrophages. Assessment of cell viability was made through a colorimetric assay using MTT on macrophages, keratinocytes, and hepatocytes. The main compounds are α-phellandrene (53.0-63.3%), terpinolene (11.9-8.6%), ß-phellandrene (5.5-6.0%), and dillapiol (1.9-8.0%). The oil demonstrated high antioxidant capacity in the concentrations tested (0.05-0.20. μL/mL) and significantly inhibited NO production without cytotoxicity in concentrations up to 1.25. μL/mL. The plants showed a high essential oil yield, which confers an industrial potential interest. Also, the high content of α-phellandrene (53.0-63.3%) makes it an important natural source of this compound. These results provide evidence of the therapeutic effects of this oil, and suggest that the anti-inflammatory activity in doses without cytotoxicity on mammalian cells, combined with its antioxidant potential and pleasant smell, could be of great value in the development of new phytopharmaceuticals.
- Sandy beach macrofaunal communities on the western coast of Portugal – Is there a steady structure under similar exposed conditions?Publication . Gonçalves, Sílvia C.; Anastácio, Pedro M.; Pardal, Miguel A.; Cardoso, Patrícia G.; Ferreira, Susana M.; Marques, João C.; Gonçalves, Sílvia; Ferreira, SusanaThe structure of macrofaunal communities at two similar exposed sandy beaches on the western coast of Portugal was monitored for approximately 18 months by sampling all the beach area, from the shoreline to the base of the dunes. The beaches' physical environment, as well as community density and composition, seasonal variations and the potential relationships between biological data and environmental parameters were studied. The two beaches had similar exposure to wave action, but differed in terms of sediment grain size, extent of the intertidal area, sediment moisture content and, especially, in the potential food availability in the form of allochthonous debris. Differences were observed with regard to the communities' structure, namely regarding composition and relative contribution of the dominant species. Seasonality, especially temperature variations, and the interaction between seasons and the beach zones (supralittoral vs. intertidal) also had a strong influence on communities: controlling dominant species' density and the horizontal distribution of the dominant species, and promoting a differential utilization of the beach by several resident macrofaunal animals. The present study allows the identification of key species in exposed sandy beaches of western Portugal and demonstrates that a steady community structure does not persist in the similarly exposed conditions observed, which may be mainly a response to distinct detritus subsidies, combined with differences in sediment grain size, sediment moisture content and extent of the intertidal area.
- Short-term impacts of air temperature on hospitalizations for mental disorders in LisbonPublication . Almendra, Ricardo; Loureiro, Adriana; Silva, Giovani; Santana, Paula; Vasconcelos, JoãoIndividuals with mental disorders are often susceptible to the effects of extreme ambient temperatures. The aim of this study is to assess the short-term impacts of daily mean temperature on hospitalizations for mental disorders in the Lisbon Metropolitan Area, Portugal. Methods: To assess the short-term impacts of daily mean temperature on hospitalizations for mental disorders (2008–2014), a quasi-Poisson generalized additive model combined with a distributed lag non-linear model was applied. The model was adjusted for day of the week, air pollution, relative humidity, time and seasonality. Results: The number of hospital admissions for mental disorder during the study period was 30,139. Hospital admissions increase significantly with high temperatures on day of exposure, at lag 0–1 and at lag 0–2.Women are more vulnerable than men, and there was no difference between the age groups studied. Conclusions: The exposure to high temperatures should be considered a significant risk factor for mental disorders; therefore, patient management services may need to be strengthened when extreme high temperature alerts are given