8 resultados para Risco versus incerteza
em Universidade dos Açores - Portugal
Resumo:
Tese de Doutoramento, Geologia (Vulcanologia), 21 de Março de 2014, Universidade dos Açores.
Resumo:
Fishing decreases the biomass of target species via reduction in the numbers and/or size of individuals. In natural systems, the strength of biological interactions, including predator-prey dynamics, are often density or size-dependent. Hence, changes in the numbers or size of key taxa may be expected to influence biological interactions but their effects do not need to be identical. Here we compare the effects of biomass reduction in populations of the exploited limpet Patella candei. Biomass removal was experimentally achieved by either removing individuals (density reduction) or by replacing large by small individuals (size reduction), while controlling for total limpet biomass in a laboratory-based experiment. At the experiment’s termination, biomass reduction led to proportional changes in area grazed. However, there was no difference whether this was achieved via changes in density or in size. Furthermore, no discernible effects of treatments were evident on different components of the algal assemblage. A field survey also revealed that P. candei biomass explained a greater proportion in variation in the area free of algae than density alone. Our results suggest that loss of biomass in populations of P. candei has quantitatively and qualitatively similar effects on algal cover regardless of whether it is caused by an equivalent (biomass) reduction in the numbers or size of individuals.
Resumo:
In this paper, we present a comparison of richness patterns and floristic similarity for bryophytes in the five most important altitudinal habitat types in the Macaronesian islands. We evaluate the importance of different factors discussed in the literature in predicting species diversity applying the traditional island approach and within the framework of the new habitat approach, including area, isolation, climatic factors, geological age and human influence. From the analysis of patterns of bryophyte species distribution for selected habitats across islands and archipelagos, we specifically test the hypothesis that (i) floristic similarity is primarily determined by climatic factors, but not by geographical distance due to high dispersal ability in this species group and (ii) bryophyte richness is best predicted by area, but not by geological age of the habitat due to very low endemicity or speciation rate and high colonization rate.
Resumo:
Dissertação de Mestrado, Engenharia do Ambiente, 12 de Junho de 2014, Universidade dos Açores.
Resumo:
Na qualidade de Diretora Regional das Comunidades, fomos responsável pela redação dos artigos e coordenação da página "Comunidades Açorianas no Mundo", integrada no jornal Mundo Português, servindo a mesma para a divulgação das atividades realizadas pela Direção Regional Das Comunidades do Governo dos Açores.
Resumo:
Dissertação de Mestrado em Ambiente, Saúde e Segurança.
Resumo:
Tese de Doutoramento, Gestão Interdisciplinar da Paisagem, 11 Fevereiro de 2016, Universidade dos Açores.
Resumo:
Dissertação de Mestrado, Psicologia da Educação, especialidade de Contextos Comunitários, 23 Fevereiro de 2016, Universidade dos Açores.