Riqueza florística de um trecho de mata úmida no Planalto da Ibiapaba, Ceará, Brasil

Abstract

The aim of this research was to carry out a floristic study and biogeographical analysis of a stretch of sedimentary humid forest at Sítio Coqueiros (SCq), in the municipality of Ipu, Ceará. Collections were made between June 2017 and October 2022, comprising rainy and dry periods. The materials were georeferenced, herborized and incorporated into the HUVA Herbarium collection. The biogeographic relationships, based on floristic similarity data, were analyzed based on information published for other humid forests in the Caatinga Phytogeographic Domain. The SCq flora was represented by 363 species, 255 genera and 89 families, with Fabaceae being the most representative with 61 species. The tree component (93 spp.) was the richest in species. Of the species recorded, 79 are endemic to Brazil, of which 17 are restricted to the Northeast region. Three new occurrences were recorded for Ceará. The floristic composition includes floristic elements exclusive to the Caatinga Domain (17 spp.), the Amazon (6 spp.), the Atlantic Forest (5 spp.) and theCerrado (2 spp.). The biogeographical analyses indicated that the SCq showed greater similarity to the Ubajara National Park, corroborating that it is indeed a humid forest area, since its floristic composition showed a greater relationship withthat of other high-altitude wetlands in the Northeast region. The data emphasize the importance of conserving the sedimentary humid forests of the Ibiapaba, since they are areas of significant floristic richness and serve as refuges for many species, whose biogeographic relationships include elements of the Amazon and the Atlantic Forest.