Archaeobotanical records in an Amazonian shell mound: microalgae (Diatomacea,Bacillariophyta) as indicators of environmental changes

Abstract

Records of the conditions during the formation of archaeological sites were obtained from interdisciplinary investigations. In archaeobotany, diatoms are microalgae that can depict these previous conditions; when present in archaeological soils, they indicate the presence of watercourses near the site or may permit inferences about paleoenvironmental conditions. This study is the first to describe the diatom record throughout the entire anthracological column of a shell mound. Samples from the Porto da Mina Shell Mound (Quatipuru, Pará, Brazil) were analyzed along the sedimentary column. The diatoms found in the mound reinforce the notion that groups have been associated with the shell mound at the site for at least 210 years. The ecological inferences indicate that the settlement was in a geographically diverse environment, with fresh, brackish, and marine water entering. The inclusion of diatom analysis in the archaeological context represents an additional technique for environmental reconstruction studies.

Keywords
Algae; Holocene; Paleoecology; Shell mound