Evolution of the landscape of Madeira Island: long-term vegetation dynamics

The aim of this thesis was to evaluate historical change of the landscape of Madeira Island and to assess spatial and temporal vegetation dynamics. In current research diverse “retrospective techniques”, such as landscape repeat photography, dendrochronology, and research of historical records were used. These, combined with vegetation relevés, aimed to gather information about landscape change, disturbance history, and vegetation successional patterns. It was found that landscape change, throughout 125 years, was higher in the last five decades manly driven by farming abandonment, building growth and exotic vegetation coverage increase. Pristine vegetation was greatly destroyed since early settlement and by the end of the nineteenth century native vegetation was highly devastated due to recurrent antropogenic disturbances. These actions also helped to block plant succession and to modify floristical assemblages, affecting as well as species richness. In places with less hemeroby, although significant growth of vegetation of lower seral stages was detected, the vegetation of most mature stages headed towards unbalance between recovery and loss, being also very vulnerable to exotic species encroachment. Recovery by native vegetation also occurred in areas formerly occupied by exotic plants and agriculture but it was almost negligible. Vegetation recovery followed the successional model currently proposed, attesting the model itself. Yet, succession was slower than espected, due to lack of favourable conditions and to recurrent disturbances. Probable tempus of each seral stage was obtained by growth rates of woody taxa estimated through dendrochronology. The exotic trees which were the dominant trees in the past (Castanea sativa and Pinus pinaster) almost vanished. Eucalyptus globulus, the current main tree of the exotic forest is being replaced by other cover types as Acacia mearnsii. The latter, along with Arundo donax, Cytisus scoparius and Pittosporum undulatum are currently the exotic species with higher invasive behaviour. However, many other exotic species have also proved to be highly pervasive and came together with the ones referred above to prevent native vegetation regeneration, to diminish biological diversity, and to block early successional phases delaying native forest recovery.

Relação entre os setores de prática desportiva, as modalidades desportivas e o aproveitamento escolar

O propósito do estudo foi verificar se o setor desportivo escolar, federado ou ambos, e as modalidades desportivas, estão relacionados com as taxas de aproveitamento escolar dos jovens em idade escolar. O estudo envolveu uma amostra aleatória estratificada dos alunos pertencentes ao 3º ciclo e ensino secundário das escolas da ilha da Madeira, Portugal, num total de 2443 alunos (12.6%). Para a recolha de dados foi construído um questionário anónimo e individual de perguntas fechadas. Os resultados indicaram que não há diferenças entre os setores desportivos no que se refere às taxas de aproveitamento escolar. Já quanto às modalidades desportivas, verificou-se que a taxa de retenção difere significativamente entre o futebol/futsal e as restantes modalidades, sendo o futebol/futsal a contemplar as maiores taxas de reprovação, enquanto a ginástica e a natação estão mais associadas às de aprovação. É necessário desenvolver mais estudos para que se identifiquem as causas de insucesso escolar evidenciadas, particularmente no futebol/futsal.