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Plant diversity and vegetation of the Andean Páramo

Plant diversity and vegetation of the Andean Páramo
Gwendolyn Peyre

2015

Faculty of Biology, University of Barcelona, 08193 Bellaterra, Barcelona, SPAIN.
AND
Institute of Bioscience, Aarhus University, 8000 Aarhus C, DENMARK.

ABSTRACT

The páramo is a high mountain ecosystem that includes all natural habitats located between the montane treeline and the permanent snowline in the humid northern Andes. Given its recent origin and continental insularity among tropical lowlands, the páramo evolved as a biodiversity hotspot, with a vascular flora of more than 3400 species and high endemism. Moreover, the páramo provides many ecosystem services for human populations, essentially water supply and carbon storage. Anthropogenic activities, mostly agriculture and burning-grazing practices, as well as climate change are major threats for the páramo’s integrity. Consequently, further scientific research and conservation strategies must be oriented towards this unique region. Botanical and ecological knowledge on the páramo is extensive but geographically heterogeneous. Moreover, most research studies and management strategies are carried out at local to national scale and given the vast extension of the páramo, regional studies are also needed. The principal limitation for regional páramo studies is the lack of a substantial source of good quality botanical data covering the entire region and freely accessible. To meet the needs for a regional data source, we created VegPáramo, a floristic and vegetation database containing 3000 vegetation plots sampled with the phytosociological method throughout the páramo region and proceeding from the existing literature and our fieldwork (Chapter 1). We made VegPáramo accessible online through a webportal, www.vegparamo.com, from which the data can be freely consulted and downloaded. We then used the VegPáramo data to conduct a regional vegetation classification of the páramo (Chapter 2). We used a clustering technique and classified the region into 17 clusters, 14 representing natural phytogeographical units of one or several plant communities and 3 artificial ensembles. We characterized the 17 clusters and calculated the alpha diversity and beta diversity to highlight species richness and floristic similarities. Our last study focused on the plant diversity patterns in the páramo region (Chapter 3). We used the VegPáramo data and our classification results to estimate and compare plant diversity at local and regional scale in the altitudinal belts of the páramo. We evaluated the importance of the environment as driver of species richness using regression models. Finally, we modeled the predicted species richness in the páramo region and highlighted biodiversity hotspots. Our project contributes to a better understanding of the páramo biogeography and makes primarily suggestions for conservation. We believe further research should focus on the climate change impacts on the páramo flora and vegetation.