Vegetation dynamics of southwestern Italy in the last 20,000 yr inferred from pollen analysis of a Tyrrhenian Sea core.

A continuous pollen record covering the last 28 kyr was obtained for core C106 collected in the Bay of Salerno, in the southern Tyrrhenian Basin. Seven radiocarbon datings and the recognition of two tephra layers (Y3 and Pompeii Pumice) provide a good chronological constraint. The clear climatic signal given by pollen spectra integrated by isotopic data, as well as comparison with other Mediterranean sites, allowed the Last Glacial, the Late Glacial and the Holocene periods to be distinguished in the core. In particular, the Last Glacial period is characterised by large amounts of herbaceous and steppe elements such as Artemisia. The beginning of the Late Glacial has been correlated with the first increase of deciduous Quercus and the reduction of steppe and herbaceous elements. The Younger Dryas event is recorded by oxygen isotops only while vegetation does not seem to change, as in other Mediterranean sites. The Holocene corresponds to rich deciduous and evergreen forests. The first features which could be interpreted as signs of human presence are represented by a few grains of Juglans, Castanea and cereal type while intensive olive cultivation and deforestation seem to fall within the Middle Ages.