Influência de gradientes ambientais na história evolutiva de comunidades arbóreas em diferentes escalas espaciais

Abstract

The study of the phylogenetic diversity (PD) of plant species and its relation with historical and ecological processes has been explored in recent decades. This approach adds knowledge about the evolutionary history of communities and aims to conserve the adaptive capacity of the species. Faced with high rates of deforestation and vegetation suppression, studies of this nature become essential, providing ways to prioritize conservation decisions. This thesis was divided into three chapters, the first being a bibliographical review of the topics that will be discussed in the second and third chapters. The second chapter deals with short-range relationships between environmental extremes linked to inselberg and flooded areas and the third chapter deals with rocky environments (inselbergs and rupicolous forests) on a large scale. The objective of this work was to understand the phylogenetic relationships in environmental gradients in short and large scale, with emphasis on environmental extremes characterized by excess and scarcity of water, as well as in rocky environments. The database used was composed of areas of NeoTropTree and surveys conducted at the Laboratory of Forest Ecology of the Federal University of Lavras. Among the analyzed areas there are evergreen, semideciduous and deciduous forests occurring in rocky outcrops, flooded, riparian, border and corridor environments. Sampling encompassed the Atlantic, Amazonian, Cerrado and Caatinga domains in eight South American countries. Among the main analyzes, we used community dynamics rates (recruitment, mortality, turnover and net change for number of individuals and gain, loss, turnover and net change in terms of basal area), PD (PD, .MPD and ses.MNTD) and beta PD. The results point to the existence of phylogenetic differentiation and temporal behavior among the communities in the environmental extremes analyzed in the second chapter, where it was concluded that only the inselberg can be characterized as stressful for the species that inhabit it. In the third chapter, we observed that there is phylogenetic niche conservatism in the analyzed rocky environments considering that areas with similar characteristics are grouped independently of their geographical position.