Comparação florística e diversidade das áreas core de savanas “cerrado” e disjunções do leste da Bahia, Brasil

Abstract

This paper aims to study the floristic of areas of Brazilian Savannas in state of Bahia and compares them to the physiognomies present in Coastal Plain in east of Bahia which are considered disjoint cerrado. The methodology of this work consisted of establish five sampling areas in the state of Bahia: 1) Savanna physiognomy in the west of Bahia; 2) In the Chapada Diamantina; 3) In the Coastal Plain; 4) Restinga in the northern littoral of Bahia; 5) Restinga in the southern littoral of Bahia. The sampling areas were performed using the point centered quarter method, being in each area were sampled 100 points 20m far between distributed in 10 transects with 10 points each, considering the degree of conservation in each study area. All woody individuals with DBH ≥ 3 cm closer to each point were sampled in that survey totaling 400 individuals per area. A sum of 2.000 individuals were sampled. The Shannon index (H') was used to estimate the diversity of each area. The Jaccard index of similarity (cluster method) was used to determine the floristic similarity between transects and study areas. Were sampled 78 species in the Western Savanna formations distributed in 31 families; estimated the diversity by the Shannon index H' = 3,61 to 3,93; 68 species in the Chapada Diamantina Savanna formations distributed in 30 families and estimated the diversity by the Shannon index between 3,49 to 3,45; 83 species in Coastal Plains distributed in 38 families wich estimated the diversity by H’ = 3,46 to 3,89; 73 and 69 species in the restingas in the Northern and Southern littoral distributed in 36 and 33 families; estimated the diversity by the Shannon index H'=3,61 to 3,97 and H’ = 3,68 to 3,85. Cluster analysis indicated that the floristic similarity found between coastal plain in the east of the State of Bahia and restinga formations (coast) indicating floristic relationship between the areas. The Savanna formations in the west of Bahia and Chapada Diamantina presented 30% of similarity. There by the analysis of this work showed more evident relationship of the floristic in Coastal Plains to the Atlantic forest physiognomy therefore these areas should be treated as Atlantic forest physiognomy related including all legal aspects of conservation and forest management provided by law nº 11.428/2006 and resolutions of CONAMA.