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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.
- 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.
- Crustaceans from temperate sandy beaches: A possible route for management and conservation strategiesPublication . Gonçalves, Sílvia; Alvarado, VictorCrustaceans are important components of the macrofaunal communities of sandy beaches worldwide and may present a key role in the structure and function of these ecosystems in certain conditions. These animals represent the dominant faunal group in exposed beaches, where some crustacean species form abundant populations, especially in the supralittoral zone. In temperate latitudes, Talitrid amphipods, commonly known as sand hoppers, and Tylid isopods are often abundant elements in exposed sandy beaches although, due to their nature, Talitrids are the most conspicuous ones. Despite their clear ecological relevance as interface systems between the sea and land, sandy beaches also constitute unique and irreplaceable habitats for most of these Crustacean species. However, the intensification of human activities in coastal areas observed in the last decades, as well as the global climatic changes and coastal erosion occurring nowadays, have introduced several detrimental impacts threatening these ecosystems and their biota. In this commentary, the relevance of using Talitrid and Tylid crustaceans as ecological tools in management and conservation strategies for temperate sandy beaches is discussed. Also, the benefits of these strategies for the conservation of the unique habitats that beaches represent for these animals are highlighted. I start by explaining the ecological importance of Crustaceans in sandy beach ecosystems worldwide. The most abundant groups in temperate beaches and their main environmental stressors are afterwards presented. Finally, specific management and conservation strategies, employing Talitrids and Tylids as ecological indicators of environmental quality condition in beaches from temperate latitudes, are identified. © 2016 by Nova Science Publishers, Inc. All rights reserved.
- Rankings and sustainability in Portuguese higher education institutions: a descriptive analysisPublication . Aleixo, Ana Marta; Leal, Susana; Leal Filho, Walter; Mendes, Susana; Azeiteiro, UlissesThe issue of ranking in Higher Education Institutions (HEIs) has produced a growing body of literature at an international level that is focused on metaanalysis. However, there is still comparably little discussion on the subject of Higher Education (HE) in Portugal. This paper strives to fill this gap. This research was conducted using the Portuguese public HEIs websites and presents a critical review of HEIs rankings in Portugal. These are the types of Higher Education Institution (HEI) rankings that are concerned with the promotion of sustainable development rankings. The links between rankings and institutional commitment, advanced sustainability or the promotion of a positive image are discussed. This work results in the preliminary discussion of a proposal for an alternative ranking for Sustainable Development (SD) in HEIs. An alternative ranking would take the system and subsystem activities of HEIs into consideration, and would constitute a starting point for further discussion when it comes to the development of the ranking for sustainability in HEIs in responding to the issue of holistic and integrated sustainability in Portuguese public HEIs.
- The impact of conspicuous environmental changes on the spatial and temporal dynamics of Acartia tonsa and Acartia clausi: A decadal study in a temperate estuary (Mondego, Portugal)Publication . Marques, Joana C.; Primo, Ana L.; Falcão, Joana; Martinho, Filipe; Mendes, Susana; Azeiteiro, Ulisses M.; Pardal, Miguel A.This chapter aimed to identify the role of natural environmental factors in the distribution of the congeneric species Acartia tonsa and Acartia clausi in the Mondego estuary, central Iberian Peninsula, over the period 2003-2012. A. tonsa was the dominant species during the study period, representing 84% of the total abundance of Acartia. The distribution patterns of Acartia species revealed a spatial segregation along the estuary, with A. tonsa confined to upstream areas, while A. clausi was restricted downstream Both species showed seasonal variation, peaking during warmer months. Since 2007, A. tonsa exibithed yearly averages consistently above the long-term mean abundance. The results identified a clear effect of temperature warming on the ecosystem, favoring and accelerating the settlement of the non-indigenous species A. tonsa at an unexpectedly rapid rate. STATICO analysis revealed that 2007, 2010 and 2011 were years with strong temporal patterns, which best fitted the compromise analyses between Acartia abundance and environmental parameters. A. tonsa showed an overall positive relationship with temperature, salinity, and total suspended solids (TSS), while A. clausi presented a positive association with chlorophyll a. Local variability of freshwater flow was the dominant signal in the present time-series, and explained the observed dynamics in Acartia populations structure at shorter temporal scales. However, this effect could be masked by larger time-scale phenomena occurring simultaneously, such as a rise in water temperature, leading to a higher abundance of opportunistic tolerant-species, as A. tonsa. These results suggest that copepods living in highly dynamic ecosystems are prone to shifts in community equilibria that show complex, non-linear responses to climatic oscillations.
- Seaweeds as fish feed additivesPublication . Afonso, Clélia; Mouga, TeresaAquaculture is becoming increasingly important to feed the growing world population. Yet, the production of fish in aquaculture systems faces several challenges, namely the vulnerability to disease outbreaks, being this one of the major problems associated with this activity. Factors such as the high density of individuals in the tanks, frequent handling and changes in temperature, water quality, poor hygiene and poor nutritional status all contribute to raising stress levels and decreasing the welfare of fish, leading to adverse effects on animal health and welfare. With increasing demand for environment friendly aquaculture, the use of prophylactic compounds in aquaculture is now widely accepted. The naturally diversity of the chemical compounds existing in marine environments is demonstrated by several examples of compounds extracted from seaweeds that are already in commercial use. The effects and benefits for the health and well-being of aquaculture fish associated with the use of additives such as immune-stimulators, and antimicrobial and antioxidant compounds is nowadays of uttermost importance. The nutritional and prebiotic effects namely due to the presence of proteins, vitamins and minerals, polysaccharides, polyunsaturated fatty acids (PUFA) and polyphenols, will also be also addressed, as well as the toxicological and potential inhibition and detrimental effects in fish.
- Conserving endemic plant species in oceanic island s protected areasPublication . Mouga, Teresa; Suratman M. N.,Oceanic islands are known for their high levels of plant diversity, due to disjunct geographical distribution that leads to speciation. The main factors contributing to genetic speciation includes the creation of a barrier within a previously widely distributed taxon and the limited dispersal of seeds, which favours genetic differentiation and, thus, fosters rapid speciation. Plant survival and population fitness vary according to environmental factors and to human interference. This chapter depicts the importance of oceanic islands as biodiversity hotspots, discusses the threats to which endemic plants on islands are exposed, namely climate change, invasive alien species, urbanisation, touristic activities, fire, changes in agriculture practices and collecting pressure. The best practices worldwide to protect endemic plant species in protected areas are also addressed, namely the implementation of prevention and mitigation actions, the programs executed to protect endemic species, and management plans to avoid future threats.
- Storage Procedures Influence the Antioxidant Capacity of Bee PollenPublication . Orvalho, Telma; Vaz, Daniela C.; Campos, Maria; Santos Ribeiro, VâniaBee products, including bee pollen, are known for their therapeutic and nutritional properties due to the presence of several nutrients (essential lipids and amino acids, fat-soluble and water-soluble vitamins and bioelements) as well as natural antioxidants, such as flavonoids (e.g.: kaempferol, quercetin, and isorhamnetin), phenolic acids (chlorogenic acid) and catechins. Therefore, given its health beneficial properties, bee pollen is considered a valuable dietary supplement to the human diet, being currently marketed, and used as a food supplement. Nonetheless, the chemical and antioxidant properties of pollen can be altered by several factors, such as improper storage, type of sample handling and processing and sample ageing. Thus, we have evaluated the influence of different processing and conservation methods (freeze-drying, drying, and freezing) in the amount of total phenolics and antioxidant capacity present in 1-year samples, submitted to the different storing procedures. Total phenolic content (TPC) was estimated spectrophotometrically by using the Folin-Ciocalteu method and nuclear magnetic resonance spectroscopy (1H NMR); while the antioxidant capacity (AC) was determined by the ABTS (2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) and DPPH (2,2-Diphenyl-1-picrylhydrazyl) methods, that measure radical scavenging activities. Different solvent extraction procedures (ethanol and acetone based) were also applied to the several samples prior to analysis. The results showed that the antioxidant activity and total phenolics reduce considerably after one year of storage, especially when bee-pollen is submitted to freezing procedures.
- Aprendizagem ativa aplicada às aulas teóricas da UC de Botânica MarinhaPublication . Mouga, TeresaÉ consensual que a inovação pedagógica desempenha um papel fundamental na formação dos estudantes, especialmente nas áreas STEM, crucial para os preparar para os desafios do século XXI. Nesse sentido, foi desenvolvido um projeto de aprendizagem ativa na UC de Botânica Marinha, da licenciatura em Biologia Marinha. A aplicação destas metodologias demonstrou resultados significativos em relação ao desempenho dos estudantes, diferenças de género e satisfação dos estudantes. Os resultados apontam para uma diferença marcante no desempenho académico entre rapazes e raparigas, com as raparigas obtendo consistentemente melhores resultados, mas a introdução destas novas metodologias teve um impacto positivo no desempenho geral dos estudantes, com uma notável melhoria na participação dos rapazes nos testes. Os estudantes fizeram uma apreciação global das aulas, mostrando uma ligeira preferência pelas aulas expositivas em relação às aulas invertidas. No entanto, ambas as abordagens são consideradas úteis e compreensíveis, indicando que a combinação de diferentes métodos pedagógicos pode ser benéfica para atender às diversas necessidades e estilos de aprendizagem dos estudantes. Finalmente, destaca-se a popularidade do escape-room como uma atividade de aprendizagem, evidenciando que abordagens criativas e envolventes podem aumentar a motivação dos estudantes e o seu interesse pelo conteúdo.
- Oxidative Stability of Sunflower Oil Enriched with Fig Tree Leaves Bioactive Compounds at Frying TemperaturePublication . Pinteus, Susete; Neves, Marta; Tecelão, Carla; Silva, Susana; Cruz, Alexandra; Bernardino, Susana; Mendes, Vasco; Vaz, Daniela; Campos, Maria Jorge; Santos Ribeiro, VâniaThe pressure imposed by the increase of world’s population and climate change makes it imperative to find sustainable strategies to optimize food resources and decrease waste production based on circular economy principles. This work evaluated the potential of fig tree leaves to reduce the oxidation of sunflower oil when exposed to frying temperatures. The bioactive compounds extracted directly from fig tree leaves were incorporated into the oil at a ratio of 12.5% (m/m), with the assistance of ultrasounds. The supplemented oil was characterized in terms of its total phenolic content (TPC), which was determined using the Folin-Ciocalteu method, and its antioxidant capacity, which was evaluated using both the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) assay and the ferric reduction antioxidant power (FRAP) assay. Also, the color of the oil and the oxidation products (K232 and K270) were analyzed. Supplementing the oil with fig tree leaves resulted in a higher antioxidant capacity compared to the control, as demonstrated by the DPPH assay (5128 ± 466 vs. 1106 ± 407 µM Trolox eq/kg oil), as well as lower levels of primary and secondary oxidation products. The results suggest that fig tree leaves can be a valuable source of antioxidant compounds with the capacity to improve the nutritional value and oxidative stability of sunflower oil under frying temperatures.