Influência da flora das florestas Amazônica e Atlântica na vegetação do cerrado sensu stricto

Abstract

The contribution of Amazonian and Atlantic floras was analyzed in twelve localities in the cerrado biome. A total of 290 tree and shrub species were recorded in those localities. Of these, 41.1% occurred only in cerrado and are probably endemic, and 58.9% also occurred in Atlantic and/or Amazonian forest. For non-endemic species the contribution of Atlantic forest was greater (44.8%) than Amazonian ones (1.4%), with the remaining 12.7% species found in both forest biomes. The proportions of species with centers of distribution in Atlantic and Amazonian forest showed a slight decrease toward the center of cerrado biome. For the former, the distance explained only 30% of variation in proportions by a polynomial model fit to the data, and for the latter a significant linear model explained 78% of variations. The flora of Amazon forest and Atlantic forest showed a segregation with altitude. The proportions of species with centers of distribution in the Atlantic forest showed a slight increase with altitude, but a polynomial model explained only 18% of this variation. Inversely, there was a linear relationship between the proportions of species with centers of distribution in Amazonian forest and altitude that explained 31% of variation. The differences in contribution patterns of the Atlantic and Amazonian forest flora to the cerrado physiognomy is discussed with respect to climatic changes during the Quaternary and to differences in plant species tolerance to fire and low temperature in the cerrado biome.