Karst carbonate outcrops cover 2.8% of Brazil's land surface and occur in all biomes. These island-like areas hold a great biogeographical interest, especially due to the influence of historical climatic fluctuations in the fragmentation and expansion of the Seasonally Deciduous Forest in the Neotropic. Karst outcrops are also a major source of aquifers, and therefore of strategic importance for water and cement production. The karst landscapes can be classified into different dissolution patterns, which may or may not be covered by soil. The mantle of weathering is formed under humid climatic conditions and it is removed by mechanical erosion of the semi-arid phases. This research seeks to generate the baseline floristic data necessary to know the species composition of vascular plants on karst in Brazil; and also to evaluate how species composition on carbonate rocks outcrops in Brazil is influenced by dissolution histories and current climatic conditions. To do so we will target searches from species and the records will be conducted on Kew's herbarium and digital databases through key terms. In addition, we will use the literature review data and the results of the candidate's doctoral thesis. The records of occurrences of specimens will be cleaned and checked. For environmental data we will classify the entire Brazilian territory according to dissolution histories and current climatic conditions. The spatial framework will be 0.5 cells degree. Each cell will be classified according to dissolution histories and current total rainfall, mean temperature, and dry season lengths conditions. The floristic composition will be obtained by the relation of the different species that occurred within each grid cell. To understanding the cells similarity according to the species composition, our analyses will perform two methods of cluster analysis. To verify the relationship between species composition and dissolution histories and current climatic conditions, we will use linear models fitted by generalized least squares. Finally, the correlation between the variables will be verified using a Pearson test. Through the results, it is expected to evaluate how species composition on carbonate rocks outcrops in Brazil is influenced by dissolution histories and current climatic conditions; thereby, it will be possible to support the understanding of the control processes of the distribution of the cover of the vegetation types in the Neotropical region.
News published in Agência FAPESP Newsletter about the scholarship: