Interpretação de texturas vegetais em fotografias aéreas para a indicação de sítios arqueológicos

Abstract

In the National Forest of Caxiuanã (Flona), located in the municipalities of Portel and Melgaço in Pará State, several sites with Terra Preta Arqueológica (TPA) were found, demonstrating that this region was intensely occupied by prehistoric populations. In a narrow strip of land on the left margin of the Caxiuanã Bay the following archaeological sites with TPA have been located: Forte, Ponta Alegre, Manduquinha, Cemitério and Itapucu. The soils with TPA have high natural fertility, in contrast to the Amazonian soils which are generally poor. These areas are known by the riverside dwellers, who use them for cultivation and/or dwelling, therefore their location in archeology is usually done through informants. The present work aims to verify the possibility of locating archeological sites based on the interpretation of the different types of plant textures found in aerial photographs. A total of 32 color aerial photographs were photographically interpreted, referring to a narrow strip of Flona, 20 photos at scale 1:20,000 and 12 photos at scale 1:5,000. The different texture patterns were also separated into fine, intermediate and coarse textures. Thus it was possible to identify and characterize three classes of vegetation formation: dense ombrophilous forest; open ombrophilous forest and shrubland, all with the constant presence of groups of palm trees. The photo interpretation did not provide conclusive data for site identification. However, the sites with the highest density of palm trees coincided with a large number of archaeological sites with TPA.