Aspects of distribution of mimosoideae (Fabaceae) trees in the highlands of santa catarina, southern Brazil

Abstract

The Santa Catarina plateau, in southern Brazil, harbors the Deciduous Seasonal Forest and the Mixed Ombrophilous Forest, both subjected to intense human pressures, which may influence the distribution and conservation status of some species. This study aimed at comparing the distribution of tree species of Mimosoideae (Fabaceae) on this plateau, based on current data of the Floristic and Forest Inventory of Santa Catarina (IFFSC) and the collection of the Illustrated Flora of Santa Catarina (FIC), which records span the period of 1950 to 1970. The geographical distribution of 17 species of Mimosoideae was analyzed using binomial statistical test of two proportions, based on information from 221 and 124 sampling units of IFFSC and FIC, respectively. Maps of the current distribution of each species were prepared based on IFFSC’s information. Comparing current data with those from 1950-1970, we found that 29.41% of the species changed their distribution and 70.59% maintained their occurrence ratios. The analysis proved to be less accurate in relation to rare species of both vegetation types. Despite the different methods used in each sampling period, we considered that the statistical method minimized the differences, enabling to indicate changes in the distribution pattern of Mimosoideae species in the last decades.