Archaeopalynological evidence of activities and relationships of pre-colonial populations with the semiarid environment, Bahia, Brazil

Abstract

This study aimed to identify palynomorphs from sediments at the Gruta da Caixa d’Água archaeological site (Caetité, Bahia, Brazil), to obtain information about plant species represented in the archaeological records. The sediment samples were chemically treated following the techniques recommended for Quaternary pollen grains at the Laboratório de Estudos Palinológicos (LAEP), Campus VII of Universidade do Estado da Bahia. Permanent slides with the sediments samples were prepared for identification/counting of palynomorphs under light microscopy. Two samples were dated based on 14C, which 5,650-5,690 Cal yr BP at the 70-80 cm level and 520-540 Cal yr BP at the 20-30 cm level. 44 pollen types were identified in seven of the ten samples analyzed and most of them were related to the families Convolvulaceae, Rubiaceae and Convolvulaceae. A greater quantity of pollen grains was recorded in the more superficial sediments samples, while they were very reduced and/or absent in the basal layers. The pollen types were related to current representatives of the local flora, with a predominance of plants of herbaceous-shrub habit, indicative of secondary vegetation resulting from possible past human interference in the vegetation. The palynological results associated with the site’s archaeological remains contributed to broadening the understanding of the relationships between pre-colonial inhabitants and the Caatinga biome environment.

Keywords
Caetité; Archaeopalynology; Cave