Holocene palaeoenvironmental evolution in the Sao Paulo State (Brazil), based on anthracology and soil δ13C analysis

This paper presents a reconstruction of the Holocene palaeoenvironmental evolution in the central Sao Paulo State (Brazil) based on anthracological analyses, in association with soil isotopic composition (delta(13)C) and radiocarbon dating from four sites. Anatomical identification of charcoal particles allows the reconstitution of past plant associations, and consequently of the vegetation and climate history. Rather precise interpretations may be achieved when associating anthracology and soil delta(13)C analysis. In the early Holocene, climate was dry and an open cerrado vegetation (savanna) covered most of this area. A cerradao (forested savanna) or a semideciduous forest existed in the. more humid localities. After 3500/3000 C-14 yr BP the climate was more humid, similar to the present, leading to the establishment of forested vegetation in all the studied sites. Comparison of these results with various palaeoenvironmental studies carried out in the Brazilian phytogeographical zone of cerrado and semideciduous forest suggests that at least its greater part presented a similar trend in the climatic evolution during the Holocene. This phytogeographical zone presented a dry climate during the early Holocene, then a more humid climate during the late Holocene. Climatic conditions similar to the present appeared from 5000 to 1000 yr BP, depending on the site.