Unidade de Investigação - MARE – Marine and Environmental Sciences Centre
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Browsing Unidade de Investigação - MARE – Marine and Environmental Sciences Centre by Field of Science and Technology (FOS) "Ciências Naturais::Ciências da Terra e do Ambiente"
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- Commentary: Macrofaunal key species as useful tools in management and assessment practices on sandy beachesPublication . Gonçalves, Sílvia; João C. MarquesSandy beaches are the most abundant coastal systems worldwide, representing approximately 3/4 of the worlds' coastlines. In the last decades, these sensitive and dynamic ecosystems have been a target of an increasing human pressure, associated with an unbridled urbanization of coastal areas, caused by the high human population growth, but also associated with recreational activities and tourism. Together with global climatic changes and coastal erosion, these processes lead to detrimental impacts and an environmental quality decline of sandy beach ecosystems, imposing an increasing need for adequate assessment and management practices. In the majority of sandy beaches, the macrofauna is a key element in ecosystem functioning, occupying a central position in the food webs. Some species exhibit abundant populations, representing the bulk of the macrofaunal communities and functioning as key species in these conditions. In this commentary we discuss the relevance and utility of macrofaunal key species as tools in beaches integrity assessment, planning of management practices and restoration projects. We start by exposing the reasons behind the selection and use of these organisms as potential tools in assessment and management practices of beaches. Several and alternative methodologies, at the population and at the community ecological levels of organization, are afterwards discussed and their advantages and drawbacks evaluated. Finally, the most relevant key species in worldwide sandy beaches, known in the literature, and with potential as assessment and management tools, are identified. Since several manmade disturbances (e.g., intense human and mechanical trampling, beach grooming with heavy mechanical equipment), and even natural disturbances (e.g., abnormal temperature regimes, frequency and intensity of storms) may cause variations in key species bioecology, with negative impacts perpetuated to the higher ecological levels, monitoring, assessment and management actions focused on this indicator species hold large potential in the fast changing scenario of nowadays, and should be encouraged.
- 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.
- The marine origin of drugsPublication . Horta, André; Alves, Celso; Pinteus, Susete; Pedrosa, RuiOutstanding research work has been done in the last 50 years, resulting in the increase of knowledge related to marine organisms as producers of high value-added biomolecules. This chapter highlights some of the main topics related with marine drug origin, with a particular emphasis on the unique marine chemical ecology environmental as critical conditions for marine drug production. Additionally, some of the most relevant marine drug success stories associated to their therapeutic use, or as research pharmacology tools, is also described, including marine toxin drugs (e.g. tetradotoxin, okadaic acid, Cytarabine, Eribulin mesylate and Ziconotide). The marine drug origin of the FDA-approved drugs, as well all the marine compounds under clinical trials evaluations (phases III, II and I), are the main targets of this chapter.
- 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.
- 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.
- Spatio-temporal structure of diatom assemblages in a temperate estuary. A STATICO analysisPublication . Mendes, Susana; Fernández-Gómez, Maria José; Resende, Paula; Pereira, Mário Jorge; Galindo-Villardón, Maria Purificación; Azeiteiro, Ulisses MirandaThis study examines the spatio-temporal structure of diatom assemblages in a temperate estuary (Ria de Aveiro, Western Portugal). Eighteen monthly surveys were conducted, from January 2002 to June 2003, at three sampling sites (at both high and low tide) along the estuarine salinity gradient. The relationship of diatom assemblages and environmental variables was analysed using the STATICO method, which has been designed for the simultaneous analysis of paired ecological tables. This method allowed examination of the stable part of the environment-diatom relationship, and also the variations of this relationship through time. The interstructure factor map showed that the relationship between the 11 environmental variables and the abundance of the 231 diatom species considered was strongest in the months May and September 2002 and January, February and May 2003. The stable part of the species-environment relationships mainly consisted of a combined phosphate, chlorophyll a and salinity gradient linked to a freshwater-marine species gradient. A more pronounced gradient was observed in January, February and May 2003. Diatom assemblages showed clear longitudinal patterns due to the presence of both marine and freshwater components. May and September 2002 had the least structured gradients with marine-estuarine species appearing in the freshwater side of the gradient. The most complete gradient in February 2003 could be considered, in terms of bio-ecological categories, as the most structured period of the year, with a combination of strong marine influence in the lower zone and freshwater influence in the upper. The best-structured gradients were during periods of a diatom bloom. Stable diatom assemblages (with a strong structure and a good fit between the diatoms and environment) are described and characterized. This study shows the efficiency of the STATICO analysis. The inclusion of space-time data analysis tools in ecological studies may therefore improve the knowledge of the dynamics of species-environmental assemblages.