Diversidade, dinâmica de populações e capacidade de produção ictiológica numa laguna costeira: a Ria de Aveiro

Doutoramento em BiologiaA ictiofauna e as variáveis ambient ais (temperatura, salinidade, oxigénio dissolvido, pH, turbidez e profundidade) foram amostradas mensalmente, na Ria de Aveiro, durante dois anos, entre Novembro de 1998 e Novembro de 2000, em 9 locais de amostragem, com a “chincha”, uma rede de arrasto tradicionalmente usada na região. Foram capturados 41 681 indivíduos de 61 espécies, com uma biomassa total de 222 quilogramas de peso fresco. As famílias mais abundantes foram Mugilidae, Atherinidae, Moronidae e Clupeidae, das quais seis espécies dominantes representaram mais de 74% da abundância total de peixes. A riqueza específica foi estatisticamente mais elevada em 1999 do que em 2000, com um pico no Verão em ambos os anos. A diversidade e a regularidade foram significativamente mais elevadas em 1999 do que em 2000 com picos na Primavera e no Outono em ambos os anos. Espacialmente, os dois índices foram mais elevados nas regiões intermédias da laguna do que na embocadura. A temperatura foi o factor abiótico que mais influenciou a distribuição da abundância da comunidade íctica, a qual está mais relacionada com as migrações sazonais do que com as migrações espaciais. A salinidade foi o factor abiótico que mais influenciou a biomassa dos peixes, embora a temperatura também tivesse sido um factor importante a considerar. Durante o séc. XX, ocorreram na laguna 92 espécies distintas pertencentes a 38 famílias de Agnatha, Chondrichthyes e Osteichthyes. Este ecossistema tem sido fortemente afectado por influências antropogénicas. Verificou-se que 13 espécies referidas no início do século não ocorrem actualmente. A comunidade íctica é na maioria troficamente dependente de pequenos crustáceos pelágicos e bênticos e/ou de detritos, embora possam alimentar-se de forma oportunista de outras presas. Atherina boyeri e A. presbyter evidenciaram comportamentos e características biológicas fortemente distintos, tais como a distribuição da frequência de comprimentos e a relação comprimento-peso dos peixes e dos otólitos. A sobreposição da dieta foi apenas notória nos indivíduos mais velhos. A combinação de estratégias alimentares diferentes em cada espécie indicou uma reduzida competição interespecífica. A produção total anual de todas as espécies ícticas da laguna estimou-se em 90,3 t ou 2,1 g.m-2.ano-1 e 106,7 t ou 2,5 g.m-2.ano-1, no primeiro e segundo ano, respectivamente. Sardina pilchardus foi a espécie que mais contribuiu para a produção íctica total lagunar (estimou-se uma produção superior a 33% da produção íctica total). As capturas da pesca profissional atingiram cerca de 300 toneladas anuais, sendo três vezes superior à produção íctica lagunar estimada. Assim, é urgente uma gestão adequada das potencialidades naturais para assegurar a biodiversidade e recursos de pesca sustentáveis no futuro.The ichthyofauna and environmental variables (temperature, salinity, dissolved oxygen, pH, turbidity and depth) were sampled monthly over a 2-year period, from November 1998 to November 2000, at 9 sites of Ria de Aveiro, with “chincha”, a traditionally-used beach-seine-type net of the region. A total of 41,681 individuals from 61 species were collected, with a total biomass of 222 Kg wet weight. Mugilidae, Atherinidae, Moronidae and Clupeidae were the most abundant families. Six species were dominant and represented more than 74% of the total fish abundance. Species richness was statistically higher in 1999 than in 2000, with a peak in summer in both years. Diversity and evenness were significantly higher in 1999 than in 2000 with peaks in spring and autumn in both years. Spatially, both indices were higher at the intermediate regions than at the lagoon mouth. Temperature was found to be the most important abiotic factor affecting the abundance distribution of fish assemblage, which is more related to the seasonal migrations rather than to spatial migrations. Salinity was the most important abiotic factor affecting the fish biomass, with temperature also having a major influence. During the 20th century, 92 distinct species and 38 families of Agnatha, Chondrichthyes and Osteichthyes occurred during the period. This ecosystem has been affected by large-scale anthropogenic influences. A total of 13 species that occurred in the beginning of the century have recently disappeared. Fish is mostly dependent on small benthic and pelagic crustaceans and/or detritus, although they can feed opportunistically on other prey. Atherina boyeri and A. presbyter showed behaviour and biological features markedly distinct as length frequency distribution, and fish and otolith lengthweight relationships. The diet overlap was only evident on older individuals and the combination of different trophic strategies of each species indicates a reduced interspecific competition. The total annual production of all fish species in the lagoon was calculated at 90.3 tonnes or 2.1 g m-2 year-1 and 106.7 tonnes or 2.5 g m-2 year-1 in the first and second year, respectively. Sardina pilchardus was considered the most important fish species with respect to fish production processes in the whole lagoon, accounting for > 33% of the total fish production in both years. Professional fisheries reached about 300 tonnes in each year, which is three times higher than the estimated lagoon fish production. Thus, careful management of natural resources seems to be urgent to ensure the biodiversity and sustainable fish stocks in the future

Avaliação em contextos de blended learning no ensino superior

Doutoramento em Educação - Supervisão e AvaliaçãoThe increasing complexity of the Information Society and the Bologna Declaration in the European context has led Higher Education (HE) institutions to revise their curricula courses, as far as the adoption of new strategies for teaching and learning as well as evaluation are concerned. It can also be emphasized that there has been a growing use of eLearning and of blended learning (bLearning) in HE, since these modes of training seem to be a very convenient option for lifelong learning. In this context, quality is taken as an essential goal in the development of the European Space for Education and Training, where HE institutions compete among themselves, and where evaluation is determinant as a promoter of this quality. Considering the problems summarized above, the research developed, based on four published scientific papers, intended to answer a set of research questions related to evaluation of bLearning contexts in HE. The study used diverse techniques and instruments (questionnaires, document analysis, and observation mediated technologies) spanning two methodological approaches: i) study of descriptive and exploratory nature and ii) case studies of bLearning modules. In the first approach an evaluation model for bLearning courses was developed, where we collected and analyzed, at a national level, the opinions of teachers with bLearning experience about the model dimensions. The case studies presented are post graduation curricular units, where bLearning teaching, learning and evaluation strategies were explored and evaluated, namely peer assessment. The main contributions of the first approach are: the process of questioning around the evaluation of bLearning courses, namely the quality assurance criteria for bLearning, as well as the model developed, providing a framework of theoretical, methodological and empirical elements that can be adapted in similar contexts. From the case studies emerged: the developed evaluation guidelines and the data collection instruments, in order to disseminate evaluation “best practices” that may be useful for other units in similar contexts. Regarding the recommendations about the evaluation of teaching of bLearning courses we emphasize: the use of versatile evaluation objects; the evaluation throughout the process and not just at the end; and the involvement of multiple evaluators, including students (whose feedback is essential to monitor the quality of teaching and learning). From the case studies we highlight: the need for discussion of evaluation frameworks to explore, and consequent increase in the transparency of the evaluation process; the increased interaction between groups; and the peer assessment as a strategy to promote active and autonomous learning. In addition to the contributions and recommendations for practice and research in the area of evaluation in bLearning contexts in HE, listed above, it also emerged from this study useful guidelines regarding educational evaluation in bLearning contexts, in order to improve the quality of teaching, learning and evaluation in such contexts.A complexidade crescente da Sociedade da Informação e a Declaração de Bolonha, no contexto Europeu, tem levado as instituições do Ensino Superior (ES) a rever os curricula dos seus cursos, preconizando-se a adoção de novas estratégias de ensino e de aprendizagem, bem como de avaliação. Realce-se também que tem havido uma crescente exploração do eLearning e do blended learning (bLearning) no ES, dado que estas modalidades de formação parecem constituir uma opção muito conveniente para a aprendizagem ao longo da vida. Neste contexto, a qualidade assume-se como meta imprescindível na construção do espaço Europeu da Educação e da Formação, onde as instituições do ES competirão, sendo determinante a avaliação como promotora dessa qualidade. Considerando a problemática acima sintetizada, a investigação desenvolvida, tendo por base quatro artigos científicos publicados, procurou dar resposta a um conjunto de questões de investigação relacionadas com a avaliação em contextos de bLearning no ES. Recorreu-se a técnicas e instrumentos diversificados (questionários, análise documental, observação mediada pelas tecnologias) abarcando duas abordagens metodológicas: i) estudo de natureza descritiva e exploratória e ii) estudos de caso relativos a módulos lecionados em bLearning. No primeiro desenvolveu-se um modelo de avaliação de cursos em bLearning, e recolheram-se e analisaram-se, a nível nacional, as perspetivas de docentes com experiência de ensino nesta modalidade, sobre as dimensões do modelo. Os estudos de caso apresentados dizem respeito a unidades curriculares de pós-graduação, onde foram exploradas e avaliadas estratégias de ensino, aprendizagem e avaliação em bLearning, nomeadamente a avaliação por pares. Como principais contributos do primeiro estudo destacam-se: o processo de questionamento em torno da avaliação de cursos em contexto de bLearning, nomeadamente sobre critérios de garantia de qualidade do bLearning, e o próprio modelo desenvolvido, fornecendo um quadro de elementos teóricos, metodológicos e empíricos que podem ser adaptados em contextos similares. Dos estudos de caso, salientam-se os referenciais de avaliação desenvolvidos e os instrumentos de recolha de dados, para além da disseminação de “boas práticas” de avaliação que poderão ser transversais e utilizáveis por outras unidades curriculares em contextos semelhantes.Como principais recomendações para a avaliação do ensino de cursos em regime de bLearning realçam-se: o uso de objetos de avaliação multifacetados; a avaliação ao longo do processo e não apenas no final; e o envolvimento de vários intervenientes, incluindo os estudantes (cujo feedback é essencial para monitorizar a qualidade do ensino e da aprendizagem). Quanto aos estudos de caso sublinha-se: a necessidade de discussão dos referenciais de avaliação a explorar, e consequente aumento da transparência do processo de avaliação; o incremento da interação entre os grupos; e a avaliação por pares como estratégia de promoção de uma aprendizagem ativa e autónoma. Para além dos contributos e recomendações para a prática e a investigação na área de avaliação em contextos de bLearning no ES, acima elencados, entende-se que emergem deste estudo orientações relevantes no que concerne à avaliação educacional em contextos de bLearning, com vista à melhoria da qualidade do ensino, da aprendizagem e da avaliação

A ictiofauna da ria de Aveiro: estrutura, dinâmica e populações

Mestrado em BiologiaO objectivo global deste trabalho consistiu em estudar aspectos da estrutura e dinâmica da ictiofauna da Ria de Aveiro, sistema lagunar estuarino com 43 km2 de extensão, em baixa-mar, que sofre influências dulçaquícolas e marinhas e fica situado entre 40º 30’-40º52’N and 8º35’-8º47W no litoral da costa Portuguesa. A ictiofauna foi capturada mensalmente, de Dezembro de 1996 a Novembro de 1997, em nove estações de amostragem dispersas pela laguna, com uma rede de pesca tradicional “chincha”. Foram também registados os seguintes parâmetros abióticos hidrológicos: temperatura, salinidade, oxigénio dissolvido e transparência. A temperatura variou entre 6,5 e 27,6ºC, a salinidade entre 0 e 41‰, o oxigénio dissolvido entre 1,2 e 11,4 mg.l-1 e a transparência entre 7,3 e 100,0%. A variação da salinidade e a transparência da água entre as estações de amostragem, assim como a variação da temperatura, salinidade e oxigénio dissolvido, ao longo dos meses, foram significativas. Foram capturados 14.598 exemplares pertencentes a 43 espécies de 21 famílias de Teleósteos. O número de espécies e densidade da ictiofauna foram mais elevados no Verão e nas estações mais perto da entrada da laguna, em especial na Barra e na Torreira, enquanto que a biomassa sofreu oscilações consideráveis ao longo dos meses e mostrou-se mais elevada nas estações mais afastadas da embocadura. As espécies marinhas sazonais foram as mais numerosas e registaram a maior biomassa e as categorias “marinha juvenil” e “estuarina residente” registaram o maior número de espécies. Mugilidae, Atherinidae e Clupeidae foram as famílias mais abundantes. Seis espécies representaram cerca de 74% da densidade total e cerca de 63% da biomassa total e ocorreram em todas as estações e em todos os meses. Pode-se concluir que a Ria de Aveiro, com elevada variação espacial e sazonal nos parâmetros abióticos, apresenta uma comunidade de peixes rica e representativa, comparada com lagunas costeiras estuarinas Europeias.The main aims of this work were to study some aspects of the structure and dynamics of the fish fauna in the Ria de Aveiro. This lagoon system (with 43 Km2 of area), which as both marine and fluvial influences, and is sited between 40º30’- 40º52’N and 8º35’-8º47’W in the coastal centre of Portugal. The ichthyofauna was sampled routinely during 12 months, between December 1996 and November 1997, at nine selected stations, with “chincha”, a traditionally-used, beach-seine-type net of the region. Abiotic parameters - temperature, salinity, dissolved oxygen and transparency - were recorded too. Temperature ranged between 6.5 and 27.6ºC, salinity between 0 and 41‰, dissolved oxygen between 1.2 and 11.4 mgl-1 and transparency between 7.3 and 100.0%. Significant differences were observed in salinity and transparency among stations and in temperature, salinity and dissolved oxygen in seasonal variation. Fourteen thousand five hundred and ninety eight specimens comprising 43 species of 21 Teleostae families were sampled. The number of species and density of fish fauna were highest in summer at stations near the lagoon entrance, specially in Barra and Torreira. The biomass considerably varied along the months and was highest in the extremes of the lagoon. Marine seasonal migratory species were most numerous and had the highest biomass, and the categories “marine juvenile” and “estuarine resident” had the highest number of species. Mugilidae, Atherinidae, Moronidae and Clupeidae were the most abundant families. Six species represented about 74% of the total fish density and 63% of total biomass and they occurred at all the stations in all the months. It was concluded that the Ria de Aveiro, with high seasonal and spatial abiotic variations, has a very rich and representative fish community compared with the European estuarine coastal lagoons

Academic Domains as Political Battlegrounds: A Global Enquiry by 99 Academics in the Fields of Education and Technology

This article theorizes the functional relationship between the human components (i.e., scholars) and nonhuman components (i.e., structural configurations) of academic domains. It is organized around the following question: in what ways have scholars formed and been formed by the structural configurations of their academic domain? The article uses as a case study the academic domain of education and technology to examine this question. Its authorship approach is innovative, with a worldwide collection of academics (99 authors) collaborating to address the proposed question based on their reflections on daily social and academic practices. This collaboration followed a three-round process of contributions via email. Analysis of these scholars’ reflective accounts was carried out, and a theoretical proposition was established from this analysis. The proposition is of a mutual (yet not necessarily balanced) power (and therefore political) relationship between the human and non-human constituents of an academic realm, with the two shaping one another. One implication of this proposition is that these non-human elements exist as political ‘actors’, just like their human counterparts, having ‘agency’ – which they exercise over humans. This turns academic domains into political (functional or dysfunctional) ‘battlefields’ wherein both humans and non-humans engage in political activities and actions that form the identity of the academic domain

Academic domains as political battlegrounds : A global enquiry by 99 academics in the fields of education and technology

Academic cognition and intelligence are ‘socially distributed’; instead of dwelling inside the single mind of an individual academic or a few academics, they are spread throughout the different minds of all academics. In this article, some mechanisms have been developed that systematically bring together these fragmented pieces of cognition and intelligence. These mechanisms jointly form a new authoring method called ‘crowd-authoring’, enabling an international crowd of academics to co-author a manuscript in an organized way. The article discusses this method, addressing the following question: What are the main mechanisms needed for a large collection of academics to collaborate on the authorship of an article? This question is addressed through a developmental endeavour wherein 101 academics of educational technology from around the world worked together in three rounds by email to compose a short article. Based on this endeavour, four mechanisms have been developed: a) a mechanism for finding a crowd of scholars; b) a mechanism for managing this crowd; c) a mechanism for analyzing the input of this crowd; and d) a scenario for software that helps automate the process of crowd-authoring. The recommendation is that crowd-authoring ought to win the attention of academic communities and funding agencies, because, given the well-connected nature of the contemporary age, the widely and commonly distributed status of academic intelligence and the increasing value of collective and democratic participation, large-scale multi-authored publications are the way forward for academic fields and wider academia in the 21st century.peerReviewe

Academic domains as political battlegrounds:A global enquiry by 99 academics in the fields of education and technology

This article theorizes the functional relationship between the human components (i.e., scholars) and non-human components (i.e., structural configurations) of academic domains. It is organized around the following question: in what ways have scholars formed and been formed by the structural configurations of their academic domain? The article uses as a case study the academic domain of education and technology to examine this question. Its authorship approach is innovative, with a worldwide collection of academics (99 authors) collaborating to address the proposed question based on their reflections on daily social and academic practices. This collaboration followed a three-round process of contributions via email. Analysis of these scholars’ reflective accounts was carried out, and a theoretical proposition was established from this analysis. The proposition is of a mutual (yet not necessarily balanced) power (and therefore political) relationship between the human and non-human constituents of an academic realm, with the two shaping one another. One implication of this proposition is that these non-human elements exist as political ‘actors’, just like their human counterparts, having ‘agency’ – which they exercise over humans. This turns academic domains into political (functional or dysfunctional) ‘battlefields’ wherein both humans and non-humans engage in political activities and actions that form the identity of the academic domain. For more information about the authorship approach, please see Al Lily AEA (2015) A crowd-authoring project on the scholarship of educational technology. Information Development. doi: 10.1177/0266666915622044.</p

Academic Domains As Political Battlegrounds: A Global Enquiry By 99 Academics in The Fields of Education and Technology

This article theorizes the functional relationship between the human components (i.e., scholars) and non-human components (i.e., structural configurations) of academic domains. It is organized around the following question: in what ways have scholars formed and been formed by the structural configurations of their academic domain? The article uses as a case study the academic domain of education and technology to examine this question. Its authorship approach is innovative, with a worldwide collection of academics (99 authors) collaborating to address the proposed question based on their reflections on daily social and academic practices. This collaboration followed a three-round process of contributions via email. Analysis of these scholars' reflective accounts was carried out, and a theoretical proposition was established from this analysis. The proposition is of a mutual (yet not necessarily balanced) power (and therefore political) relationship between the human and non-human constituents of an academic realm, with the two shaping one another. One implication of this proposition is that these non-human elements exist as political actors', just like their human counterparts, having agency' - which they exercise over humans. This turns academic domains into political (functional or dysfunctional) battlefields' wherein both humans and non-humans engage in political activities and actions that form the identity of the academic domain. For more information about the authorship approach, please see Al Lily AEA (2015) A crowd-authoring project on the scholarship of educational technology. Information Development. doi: 10.1177/0266666915622044.Wo