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MUS 800

Dissertação apresentada à Escola Superior de Educação do Instituto Politécnico de Castelo Branco para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Atividade Física - Motricidade Infantil.

Research Highlights: This study bridges a gap of knowledge about the maximum size–density trajectory for juvenile stands of maritime pine. The continuity of the trajectory along the development stages to maturity is assured with a straightforward approach providing support to determine optimum density along all the revolution periods for the species. Background and Objectives: Forest fire is a significant threat to forests in the Mediterranean regions, but also a natural disturbance that plays a vital role in the perpetuation of forest stands. In recent decades, there has been an increase of burnt area in maritime forests in Portugal, followed by an increased interest in managing the natural and usually abundant regeneration occurring after the fires. The gap in the knowledge of growth dynamics for juvenile stages, for these forest systems, currently constrains their correct management, for forest planning, particularly in determining the optimal densities. The study aims to identify the maximum attainable density trajectory at the early stages of development of the species that could support a non-empirical definition of silvicultural prescriptions and thinning decisions, along the revolution. Materials and Methods: A representative data set collected in stands regenerated after fire supports the analysis of the maximum size–density trajectory for the species. Results: The maximum size–density trajectory for the juvenile stands deviates from the expected trajectory defined in the self-thinning line published for the species. Significant deviation occurs at the lower end of the line, indicating the need for a reevaluation of the existing self-thinning line. We propose a new self-thinning model for the species that explicitly considers the behavior of size–density for juvenile stands. The new model assures a logical continuity for the trajectory from the young stages of development to maturity. Conclusions: The proposed model based on the maximum attainable size–density trajectory provides ecological-based support to define silvicultural guidelines for management of the species.

The present investigation intends to study if the importance and the difficulty of the game, if the pre-competitive anxiety (somatic and cognitive) and the levels of self-confidence in football were influenced by the competitive level (Under 12s and Seniors) and where the game took place (home / outside) and to verify the correlations between these variables. The sample was intentional and consisted of 85 male athletes, participants in the regional championship of «Under 12s» and Seniors. The «Under 12s» athletes (35) were aged between 11 and 12 years (M = 11.02 ± 0.37) and the Senior athletes (50) were aged between 18 and 35 years (M = 26.66 ± 4.41). The instrument used was the Competitive State Anxiety Inventory (CSAI-2) of Martens et al. (1990) and translated and validated into the Portuguese language by Raposo & Fernandes (2004). Regarding statistical procedures we tested the sample distribution through the Kolmogorov-Smirnov Test. For a normal distribution, we used the T-student parametric test for independent samples. Correlations between the variables were determined using the Pearson correlation coefficient, and we applied linear regression according to the variable’s importance and difficulty of the games for both age groups. We also applied an inferential method based on the magnitude of effects through d-Cohen and r-Cohen. We adopted a significance level of p dŠ 0.05. The results showed that, regardless of the competitive level (Under 12s or Seniors), athletes attributed high levels of importance and difficulty to games played both at home and outside. The levels of importance and difficulty of the games, as well as the levels of cognitive and somatic anxiety were higher in the Under 12s teams, although without significant differences compared to Seniors’ teams, whereas the levels of self-confidence were significantly higher in the Seniors’ teams. In both groups positive correlations were observed between the difficulty of the game and its importance, promoting these variables in general terms and in both levels an increase of anxiety and a decrease in self-confidence. The results were abounding that the importance and the difficulty of the games explain residually in the levels of Under 12s and Seniors the states of anxiety and selfconfidence.