Browsing by Issue Date, starting with "2018-07"
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- Exploratory analysis of the productivity of carob tree (Ceratonia siliqua) orchards conducted under dry-farming conditionsPublication . Correia, Pedro José; Pestana, MaribelaIn Southern Portugal (Algarve), the occurrence of extreme climatic events has become more limiting to agriculture and forestry productivity. Severe or moderate drought during spring, summer, and autumn is common, with major implications on yield, farmers income, and on a long-term basis, land use. Facing this scenario, farmers rely on certain crops in order to obtain a complementary revenue, as an alternative to more intensive and high-demanding farming. One of these crops is carob tree, a multipurpose and industrial fruit tree species very well adapted to dry-farming conditions and very important to the sustainability of these fragile agroecosystems. The aim of this study is to analyse the fruit productivity during 30 years in two mature carob tree orchards grown in two contrasting soils: a fertile, calcareous soil and in a non-fertile soil. Based on this exploratory analysis, the gross income of farmers obtained from fruit selling in the regional market is discussed. Moreover, the possibility of using tree carbon sequestration as an ecosystem service shall be considered as a novel alternative in these depreciated agroecosystems.
- Effects of reallocating fishing effort from trawling to creels in a Norway lobster fisheryPublication . Eichert, Moritz; Campos, Aida; Fonseca, Paulo; Lopes, Pedro; Marques, Lino; Castro, MargaridaThe consequences of reallocating fishing effort from trawling to creels in an area off the West coast of Portugal for the operation of the trawl fleet, as well as on the population dynamics and the global catch value for a high valued species, the Norway lobster (Nephrops norvegicus) are evaluated. The results suggest that only small portions of the area of interest are used by the trawl fleet, opening the possibility for a trawl ban without major disruption of the trawling activity. Economic benefits are expected, since predictions two scenarios tested, heavy and moderate exploitation, indicate no loss of catch value with much lower operational costs. Social benefits to local communities can also be expected since a much lower investment is needed for creel fishing, making this fishery attractive to small local companies already operating in the region. The proposed ban is consistent with the ecosystem approach to fisheries management and the Common Fisheries Policy (CFP) where the transition towards more responsible fishing practices is encouraged.
- Marine forests of the Mediterranean-Atlantic Cystoseira tamariscifolia complex show a southern Iberian genetic hotspot and no reproductive isolation in parapatryPublication . Bermejo, Ricardo; Chefaoui, Rosa M.; Engelen, Aschwin H.; Buonomo, Roberto; Neiva, J.; Ferreira-Costa, Joana; Pearson, Gareth; Marba, Nuria; Duarte, Carlos M.; Airoldi, Laura; Hernandez, Ignacio; Guiry, Michael D.; Serrao, Ester A.Climate-driven range-shifts create evolutionary opportunities for allopatric divergence and subsequent contact, leading to genetic structuration and hybrid zones. We investigate how these processes influenced the evolution of a complex of three closely related Cystoseira spp., which are a key component of the Mediterranean-Atlantic seaweed forests that are undergoing population declines. The C. tamariscifolia complex, composed of C. tamariscifolia s.s., C. amentacea and C. mediterranea, have indistinct boundaries and natural hybridization is suspected. Our aims are to (1) infer the genetic structure and diversity of these species throughout their distribution ranges using microsatellite markers to identify ancient versus recent geographical populations, contact zones and reproductive barriers, and (2) hindcast past distributions using niche models to investigate the influence of past range shifts on genetic divergence at multiple spatial scales. Results supported a single, morphologically plastic species the genetic structure of which was incongruent with a priori species assignments. The low diversity and low singularity in northern European populations suggest recent colonization after the LGM. The southern Iberian genetic hotspot most likely results from the role of this area as a climatic refugium or a secondary contact zone between differentiated populations or both. We hypothesize that life-history traits (selfing, low dispersal) and prior colonization effects, rather than reproductive barriers, might explain the observed genetic discontinuities.
- Elevated seawater temperatures decrease microbial diversity in the gut of mytilus coruscusPublication . Li, Yi-Feng; Yang, Na; Liang, Xiao; Yoshida, Asami; Osatomi, Kiyoshi; Power, Deborah; Batista, Frederico; Yang, Jin-LongThe gut microbial community is critical for the host immune system, and in recent years, it has been extensively studied in vertebrates using 'omic' technologies. In contrast, knowledge about how the interactions between water temperature and diet affect the gut microbiota of marine invertebrates that do not thermoregulate is much less studied. In the present study, the effect of elevated seawater temperature and diet (Isochrysis zhanjiangensis and Platymonas helgolandica var. tsingtaoensis) on the gut microbial community of the commercial mussel, Mytilus coruscus, was investigated. The 16S rRNA gene sequencing was used to characterize the microbial community in M. coruscus gut. The mortality of M. coruscus exposed to a high water temperature (31 degrees C) increased after 3 days and the diversity of the bacterial community in the gut of live M. coruscus was significantly reduced. For example, the abundance of Bacteroides (Bacteroidetes) and norank_Marinilabiaceae (Bacteroidetes) increased in the gut of M. coruscus fed I. zhanjiangensis. In M. coruscus fed P. helgolandica, the abundance of Arcobacter (Proteobacteria) and norank_Marinilabiaceae increased and the abundance of unclassified_Flavobacteriaceae (Bacteroidetes) decreased. The results obtained in the present study suggest that high temperatures favored the proliferation of opportunistic bacteria, including Bacteroides and Arcobacter, which may increase host susceptibility to disease. Microbial community composition of the gut in live M. coruscus was not impacted by the microalgal diet but it was modified in the group of mussels that died. The present study provides insight into the potential effects on the gut microbiome and mussel-bacteria interactions of rising seawater temperatures.
- Experimental test methodology to evaluate sound propagation paths between interior spaces of buildingsPublication . Gervásio, Nuno; Carreira, A. S.; Rosão, VitorWhen is detected in situ the existence of poor sound insulation, typically the non-compliance with the acoustic requirements of buildings, between two spaces – source and receiver - and if we want to solve the problem, it is necessary to know which sound paths most contribute to the difference of sound levels between these spaces. However, the classical sound insulation measurement does not make this distinction, it only provides the difference in sound levels. In order to overcome this difficulty, a new test methodology is proposed to estimate the sound propagation paths between building rooms, generated by sound sources located in the interior. The proposed methodology is based on the use of vibration measurements of structural elements (slabs) and non-structural elements (parti-tion walls) to estimate the sound field in the receiver space, together with sound measure-ments to estimate the sound field in the source space. With this alternative methodology to determine the sound insulation of a space, it is intended to obtain more rigorous results with respect to: i) determination of the contribution of each of the structural paths, in a certain sound isolation, in order to define the sound paths in which an acoustic rehabilita-tion intervention is most effective; ii) determining the possible existence of airborne paths that contribute to the reduction of sound insulation. In order to validate the proposed methodology, in situ sound insulation measurements were carried out, according to the applicable standards of ISO 16283 series, and vibration measurements of the separator el-ements (floor, ceiling, side walls) of interior spaces in existing buildings.
- Alguns aspetos da floração e vingamento do abacateiroPublication . Duarte, Amílcar; Lopes, Rosário; Furtado, José; Duarte, JoãoPara quem não conheça a planta, até pode parecer que o abacateiro não tem flores, porque estas são de reduzida dimensão (cerca de 1 cm de diâmetro, quando a flor está aberta) e pouco vistosas. A sua cor, entre o verde pálido e o amarelo, faz com que se possam confundir com os caules e as folhas. Porém, a floração do abacateiro é habitualmente abundante; uma árvore pode produzir mais de um milhão de flores. No caso das plantas cultivadas no Algarve, a quantidade de flores produzidas, geralmente, não constitui uma limitação para a obtenção de elevadas colheitas nesta espécie, mas o vingamento do fruto não é muito elevado e as produções são algo inferiores às obtidas em algumas outras zonas de produção. As flores do abacateiro estão agrupadas em inflorescências (panículas) situadas na zona terminal dos ramos. O conjunto das inflorescências de cada ramo pode ter várias centenas de flores, embora o número seja variável, dependendo da cultivar, das condições edafoclimáticas e da idade do ramo.
- Alimentação saudável, um guia para escolhas alimentares saudáveis e acertadasPublication . Edmundo, Sofia; Jardim, Conceição; Bôto, Joana Margarida; Braz, NídiaEste guia contém orientações para escolhas alimentares saudáveis e acertadas. Apresenta informação sobre como planear refeições, escolher os alimentos e as suas técnicas de confecção culinária mais saudáveis.
- Touch-screen-guided task reveals a prosocial choice tendency by chimpanzees (Pan troglodytes)Publication . Mendonça, Renata S.; Dahl, Christoph D.; Carvalho, Susana; Matsuzawa, Tetsuro; Adachi, IkumaHumans help others even without direct benefit for themselves. However, the nature of altruistic (i.e., only the other benefits) and prosocial (i.e., self and other both benefit) behaviors in our closest living relative, the chimpanzee, remains controversial. To address this further, we developed a touch-screen-guided task that allowed us to increase the number of trials for a thorough test of chimpanzees' prosocial and altruistic tendencies. Mother-offspring dyads were tested in the same compartment; one was the actor while the other was the recipient. In Experiment 1, the actor chose among three options: prosocial, selfish (only the actor benefited) and altruistic. To better understand the nature of the chimpanzees' choices and to improve experimental control, we conducted two additional experiments. Experiment 2 consisted of two-option choices interspersed with three-option choices, and in Experiment 3 the two-option choice were blocked across all trials. The results of Experiment 1 clearly showed that chimpanzees acted prosocially in the touch-screen-guided task, choosing the prosocial option on an average of 79% of choices. Five out of the six chimpanzees showed the preference to act prosocially against chance level. The preference for the prosocial option persisted when conditions were changed in Experiments 2 and 3. When only selfish and altruistic options were available in Experiments 2 and 3, chimpanzees preferred the selfish option. These results suggest that (1) most individuals understood the nature of the task and modified their behavior according to the available options, (2) five out of the six chimpanzees chose to act prosocially when they had the option to, and (3) offspring counterbalanced between altruistic and selfish, when given those two options perhaps to avoid suffering repercussions from the mother.
- Digital culture – a state of the artPublication . Tavares, Mirian; Boto, SandraEscrever sobre Cultura Digital é, em última, e em primeira instância, escrever sobre a cultura em si mesma. Contemporaneamente os discursos que se produzem são sempre atravessados pelas tecnologias que geraram uma nova lógica para a produção, distribuição e consumo do conhecimento. Negar a omnipresença do digital é negar um facto tão simples como este: as ferramentas que usamos para produzir textos, ou imagens, são, na sua imensa maioria, digitais. O analógico tornou-se objeto de culto, ou de museu, sendo retomado, em novas vagas, motivado às vezes pelo saudosismo, por alguma vontade de resistência ou por necessidade gerada pela investigação. A ideia de cultura, no plural, remete-nos para a polissemia do termo e o sentido que o mesmo adquire através dos usos e dos costumes e, sobretudo, através da difusão pelos media. A cultura assume, paulatinamente, o lugar da civilização, deixando de ser apenas o substrato espiritual e intelectual que identificava um grupo, ou até uma nação, para se converter num bem material, ou num rótulo utilizado para se vender um produto, ou uma ideologia, qualquer que ela seja. O universo digital é recente, mas já bastante vasto e as discussões sobre ele estão a decorrer neste momento, apesar de sabermos que somente a distância temporal nos dará uma verdadeira perspetiva das marcas e do rasto que as criações alfanuméricas deixarão impressas, de forma indelével, na cultura.
- Assessing, quantifying and valuing the ecosystem services of coastal lagoonsPublication . Newton, Alice; Brito, Ana C.; Icely, John; Derolez, Valerie; Clara, Ines; Angus, Stewart; Schernewski, Gerald; Inacio, Miguel; Lillebo, Ana I.; Sousa, Ana I.; Bejaoui, Bechir; Solidoro, Cosimo; Tosic, Marko; Canedo-Arguelles, Miguel; Yamamuro, Masumi; Reizopoulou, Sofia; Tseng, Hsiao-Chun; Canu, Donata; Roselli, Leonilde; Maanan, Mohamed; Cristina, Sónia; Carolina Ruiz-Fernandez, Ana; de Lima, Ricardo F.; Kjerfve, Bjorn; Rubio-Cisneros, Nadia; Perez-Ruzafa, Angel; Marcos, Concepcion; Pastres, Roberto; Pranovi, Fabio; Snoussi, Maria; Turpie, Jane; Tuchkovenko, Yurii; Dyack, Brenda; Brookes, Justin; Povilanskas, Ramunas; Khokhlov, ValeriyThe natural conservation of coastal lagoons is important not only for their ecological importance, but also because of the valuable ecosystem services they provide for human welfare and wellbeing. Coastal lagoons are shallow semi-enclosed systems that support important habitats such as wetlands, mangroves, salt-marshes and seagrass meadows, as well as a rich biodiversity. Coastal lagoons are also complex social-ecological systems with ecosystem services that provide livelihoods, wellbeing and welfare to humans. This study assessed, quantified and valued the ecosystem services of 32 coastal lagoons. The main findings of the study are: (i) the definitions of ecosystem services are still not generally accepted; (ii) the quantification of ecosystem services is made in many different ways, using different units; (iii) the evaluation in monetary terms of some ecosystem service is problematic, often relying on non-monetary evaluation methods; (iv) when ecosystem services are valued in monetary terms, this may represent very different human benefits; and, (v) different aspects of climate change, including increasing temperature, sea-level rise and changes in rainfall patterns threaten the valuable ecosystem services of coastal lagoons.