Climate change and topography as drivers of Latin American biome dynamics

This thesis focuses on Latin America. It uses paleobotanic data which are indicative of past vegetation and climate change on the basis of relationships between fossils left by the modern vegetation and modern environmental conditions. For the first time, palynological data is analyzed spatially in a Geographic Information System (GIS) and linked to climate change and the processes ('climate modes') that are driving these changes. Finally, long pollen records are used as source of information to derive the spatial dynamics of mountain ecosystems during the last million years of Pleistocene. On the basis of a newly developed concept of the relationship between the mountain profile and the fragmentation of the páramo ecosystem under a constantly changing climate, for the first time it was qualitatively defined where the páramo ecosystem had often become fragmented or even completely disappeared, while determining quantitatively how much time of Pleistocene corridors existed between different parts of the archipelago of páramo islands, or if connections were discontinued. The latter has major consequences for the species in mountainous areas and plays an important role in explaining current patterns of biodiversity.