This thesis set out to investigate the influence of disturbance on the succession of the Krakatau islands (Rakata, Sertung, Panjang). The hierarchical model of succession by S. Pickett and colleagues (1987) was adopted as a research framework, and provided the basis for an alternative model of succession on Krakatau that focuses on processes rather than successional pathways. Investigations were conducted on (i) the meso-scale, and (ii) the patch-scale, (i) quantified the recent disturbance regime, and inter- and intra-island differences in diversity, (ii) compared sapling performance (growth, mortality and recruitment), and species compositional patterning in space and time for saplings and the seed bank with respect to island, gap size and severity of disturbance. Multivariate techniques were used, and amongst other attempts at characterising the light environment, hemispherical photography was employed. For the first time the effect of a continuous period of volcanic activity (1992-1995) of Anak Krakatau could be directly quantified and compared between Panjang and Sertung (ash-affected) and Rakata (receiving no ash). Increased rates of gap formation in the volcanically active period in comparison to the previous decade were found for all islands. This supports the disturbance-driven model of Whittaker and colleagues. However, an extension is required, because, contrary to expectation, Rakata also experienced more disturbance. This increase is argued to be a result of more severe weather conditions, and an increased number of earth tremors, during times of volcanic activity. The disturbance factors of extreme climatic events (e.g. ENSO events) and human impact are also proposed for inclusion in the alternative model. Drought associated with the 1994 El Niño is of relevance to short-term and potential long-term impact on regeneration dynamics and succession. Attention was drawn to the local human influence of pumice mining on the coastal forests. Supporting previous findings on the plot- and whole island scales, data from species presence/absence transects established that species richness and beta-diversity on the ash- affected islands was also lower on the meso-scale. Panjang's canopy composition is less uniform, and locally more species-rich than Sertung's. More evidence of the suggested decline of the mono-dominant species Neonauclea calycina and Timonius compressicaulis was gathered. The third dominant, Dysoxylum gaudichaudianum, is expanding in the lowlands of all islands. This is aided by its ability to regenerate in moderate shade, to grow rapidly in gap environments, and its tolerance of ash-fall, drought and herbivory. However, on Rakata, it is not expected to become generally mono-dominant because a considerable number of other potential canopy species are present. Sapling performance and species composition and its changes were in general strongly affected by ash-fall and drought. These factors tended to override effects of gap size and severity of disturbance. Advance regeneration, and the composition of the local forest type were identified as important factors influencing the composition of the early stages of gap-fill. The local forest type also seemed to contribute most to seed bank composition. As rarer species tended to have clumped distributions, and 'safe sites' for regeneration seemed not to be limiting, dispersal constraints were argued to be the most likely factors slowing diversification, unless further severe volcanic disturbance leads to successional set-back. The latter also strongly limits the predictability of succession on Krakatau.

[pt] Esta dissertação faz um estudo sobre a geração de efeitos visuais (VFX) a partir da captura de objetos em movimento como nuvens muito densas de pontos utilizando múltiplas câmeras RGB-D de baixo custo. Para este estudo, são utilizados um software comercial para renderização de partículas e alguns módulos já desenvolvidos pelo Departamento de P&D em VFX da TV Globo em parceria com o laboratório ICAD/VisionLab para a captura simultânea de múltiplas câmeras MS Kinect. No pipeline de produção proposto, um servidor sincroniza os disparos das várias câmeras, unifica as nuvens e gera um arquivo em formato padrão (PRP ou PLY). Este arquivo é, então, utilizado para a renderização de partículas volumétricas com adição de efeitos visuais utilizando o software Krakatoa MX para o 3DS Max. O objetivo é filmar cenas de maneira que o diretor possa posteriormente definir as cenas finais com qualquer trajetória de câmera e adicionar efeitos visuais. / [en] This dissertation is an investigation on the generation of visual effects (VFX) from the capture of moving objects as very dense point clouds using multiple low-cost RGB-D cameras. For this investigation, we use a commercial software for particle rendering and some modules already developed by the Department of VFX R&D of TV Globo in partnership with ICAD/VisionLab laboratory for the simultaneous capture of multiple MS Kinect cameras. In the proposed production pipeline, a server synchronizes the shooting of multiple cameras, unifies the clouds and generates a file in standard format (PRP or PLY). This file is then used for volumetric particle rendering with added visual effects using the Krakatoa MX software for 3DS Max. The goal is to shoot scenes in such a way that the film director can later define the final scenes with any camera path and adding visual effects.