A NEW POLLEN SEQUENCE FROM A HIGHLAND PEATBOG (BURUNDI)

This paper presents the pollen analysis of a core, 11.5 m long, from a valley peatbog in the Burundi highlands, east of Lake Tanganyika. Nine radiocarbon dates provide a chronological frame of ca. > 32,500 to 3200 yr B.P. At the bottom of the fossil sequence, pollen spectra indicate that open grassland occurred at 2000 m altitude during the last Glacial period. The pollen diagram mostly documents the composition and history of the humid montane forest during the Holocene time. The forest starts at ca. 9500 B.P. extrapolated date, with maximum development maintained until 6000 yr B.P. Several forest decreases are documented since 4000 yr B.P., without any clear pollen indicator of anthropogenic activity. The most important one at ca. 3200 yr B.P., appears synchronous with an early date for the Iron Age in Burundi.