Holocene palynological analysis of the Alto del Mercado county, Marinilla, Antioquia

Abstract

A palynological analysis was conducted in a stratigraphical section in the Alto del Mercado County in the Central Andes Cordillera (SE of Medellín, Antioquia, Colombia). In a column of 73 cm were studied 19 samples. Four palynological zones were established based on cluster analysis. These zones reflect changes in the plant assemblages associated to human disturbance and climatic variations. The comparison between biostratigraphy and cultural stratigraphy suggests an early human intervention in the area around (2480 ± 80 yr B.P.), where communities managed selectively the vegetation especially as a food resource. This is evidenced by the presence of cultivated species like Amaranthus sp. Later (790 ± 70 yr B.P.),the number of species of cultivable plants as well their abundance increased, including not only Amaranthus sp. but also Zea Mays and Phaseolus sp. This last event coincides with the maximum amount of cultural traces found in the section.