Characterization and Distribution of Pyrogenic Carbon in a Fraction of Archaeological Black Earth from Caxiuanã

AUTOR(ES)

Moraes, Milena Carvalho, Lemos, Vanda Porpino, Moraes, Dorsan Santos, Moraes, Cláudio Nery Lamarão

FONTE

J. Braz. Chem. Soc.

DATA DE PUBLICAÇÃO

2015-08

RESUMO

This study aims to determine the atomic ratio of O/C in an archaeological black earth (ABE) profile of the Ilha de Terra site, a region of Caxiuanã in the Pará State, Brazil, to determine the types of pyrogenic carbon (PyC) particles and to infer the source of biomass and burning temperature necessary to produce the PyC. The O/C ratios were monitored using scanning electron microscopy combined with energy dispersive spectroscopy (SEM/EDS). The results indicated atomic ratios for clay, silt and fine sand fractions that were between those registered for the PyC particles types: condensed combustion (CC) (0.09, 0.1, 0.13), charcoal (0.32, 0.31, 0.34) and char (0.43, 0.45, 0.52). CC is the predominant type of particle found because of the high firing temperature (> 350 °C), which is consistent with the probable biomass sources of wood, cellulose and lignin.

Documentos Relacionados

• Nutrients in Amazonian Black Earth from Caxiuanã Region
• Distribution and availability of copper, iron, manganese and zinc in the archaeological black earth profile from the Amazon region
• Black carbon contents and distribution in sediments from the southeastern Brazilian coast (Guanabara Bay)
• Pedogenesis in an Archaeological Dark Earth – Mulatto Earth Catena over Volcanic Rocks in Western Amazonia, Brazil
• Bacterial diversity of the 16S rRNA gene in pyrogenic black carbon of Anthropogenic Dark Earth from the Central and Oriental Amazon