Flora of the Spix and Martius expedition in Piauí: a 200 year later parallel

Abstract

The floristic composition of a place can be changed by human actions, such as agricultural activities, farming, and construction and by natural factors, such as soil type, phenology, and fires. This study recorded the current flora of the region traveled by J. B. von Spix and C. F. P. von Martius in Piauí state, Brazil, comparing the data with species from the same region described in the Flora Brasiliensis. Data were collected in May 2019. A total of 157 species belonging to 113 genera and 36 families were catalogued. The presence of endemic species from the Caatinga and Cerrado biomes and the first occurrence of Chorchorus hirtus L. in the state were recorded. In the Flora Brasiliensis, 166 species, 107 genera, and 38 families were listed for Piauí. When comparing the species recorded in Flora Brasiliensis with the survey carried out in this study, 200 years later, at a family level, Fabaceae, Poaceae, and Malvaceae had the largest number of species, but the listed species did not show high correlation. It is believed that mainly environmental changes, such as reduction of areas with aquatic vegetation, growth of cities, and anthropogenic actions, such as deforestation in the area covered by the European researchers are reasons for the discrepancy in the listed flora.