Vegetation structure and edaphic factors in veredas reflect different conservation status in these threatened areas.

Abstract

Background: in Cerrado humid areas, veredas are considered as hygrophilous communities, marked by the presence of the Mauritia flexuosa palm tree emerging in the wetter zones. Changes in veredas ecosystems due to drought and changes in the water table, which represent important areas for biodiversity maintenance in the Brazilian cerrado, can lead to the emergence of new landscapes and ecosystems. Assuming that the veredas are changed in species composition due to anthropogenic factors, in this study, we evaluated the flora composition and described the current vegetation profile of two veredas under different disturbances levels that are located in the north of Minas Gerais State, Brazil. Results: altogether, 2,268 individuals of 91 species belonging to 36 families were recorded. Our results demonstrated that the studied veredas were floristically different in terms of the arboreous-shrubby species composition, richness, and diversity. Despite the hygrophilous forest formations and open areas in the two veredas present typical species from these environments (same species with high importance values), the drought in the water table caused an expansion of Cerrado species in the open areas and in the hygrophilous forest. Furthermore, in the hygrophilous forest there was an increase in the abundance of species that occur in less saturated soils. Conclusion: our results demonstrate that the studied veredas are changing in species composition due to anthropogenic factors which leads to the drought of these formations (water balance effect). These anthropogenic effects cause a modification with the expansion and increase in the abundance of typical species of other areas of Cerrado and resistant to less saturated soils, leading to the veredas collapse. Finally, future studies should investigate other veredas on a broader scale to detect changes in the water table that lead to a consequent change in vegetation structure. In this way, we will have support for the conscientious management and conservation of these areas that represent equilibrium places for the Cerrado biome.