CLIMATIC RECONSTRUCTION DURING THE MIDDLE PLEISTOCENE - A POLLEN RECORD FROM VALLO-DI-DIANO (SOUTHERN ITALY)

A long lacustrine sequence drilled in the Vallo di Diano paleolake (So uthern Italy) has yielded a continuous pollen record. Ar-40/Ar-39 dati ng at the base of the sequence and pollen data allow a precise chronol ogy to be proposed. Moreover, oxygen isotope data (delta(18)O) establi shed for the lacustrine succession are correlated with the marine isot ope stratigraphy. The pollen record covers the period between ca. 650 kyr BP and ca. 450 kyr BP, the deposit is considered as continuous and spans the isotope stages 16 to 13. A quantitative pollen study allowe d to reconstruct the palaeoclimates and to correlate the vegetational changes with two glacial-interglacial cycles of the Middle Pleistocene . Four climatic variables have been inferred: the annual precipitation , the annual temperature, the January temperature, and the July temper ature. The method used to reconstruct past climates from pollen data i s the ''Best Modern Analogue'' method. The two cold and arid intervals characterised by open vegetation are related to isotopic stages 16 an d 14. The alternating warm and humid intervals characterised by a well developed forest cor respond to isotopic stages 15 and 13. The climat ic data correlate well with the variations of the sea surface temperat ure recorded in the Atlantic Ocean at about the same latitudes. The re sults obtained from the Vallo di Diano pollen record represent one of the most detailed climatic reconstructions in southern Italy and give a contribution to the continent-ocean correlation during isotopic stag es 16 to 13 in Europe.