Pollen and charcoal analysis of a 5.3-m sediment core from
Aguada Petapilla, a peat bog, provides evidence of late Holocene
vegetation and fire history in the Copan Valley, Honduras. Low
concentration and preservation problems characterized the pollen
flora, but there are taxa present indicative of major agricultural
trends, including Zea mays. Microscopic charcoal fragments
are well represented and record continued burning in the region
since the lowest level of the core (5700 B.P. [3750 B.C.]).
Presence of Zea indicates that maize farming was initiated
by as early as 2300 B.C. Three peaks in charcoal-fragment frequencies
occur in periods centered approximately at 900 B.C., 400 B.C., and
A.D. 600. Fires in this relatively dry region of the southern Maya
Lowlands (whose mean annual rainfall is about 1,400 mm) could have
resulted from natural forest fires or human agricultural clearing at
any time in the Holocene. This contrasts with wetter areas of tropical
Central and South America (mean annual rainfall of about
2,500–4,000 mm) where significant climatic drying is required
to ignite primary tropical forest.