AnaliSi Polliniche Di Una Serie Stratigrafica Dei Sedimenti LacuStri Del PleiStocene Inferiore Nel Bacino Di Leonessa (Rieti- Italia Centrale)

Abstract

Pollen analysis of a stratigraphical sequence of the lower Pleistocene lacustrine sediments of the Leonessa basin (Rieti, Central Italy). — The Leonessa basin (Central Italy) is located at an average altitude of 900 metres above sea level. A stratigraphical sequence of some 200 metres reached by perforation of the sediments was investigated by a pollen analysis of various samples. From a chronological viewpoint, the forest whole discovered there, amongst which Cedrus, Carya, Tsuga, etc. has made' it possible to correlate the basin to others of northern and central Italy, attributed to the lower Pleistocene. The long period of forest history contained in the series examined (as shown in the diagram) represents a bioclimatological succession of a favourable and prosperous nature, excepting three periods of deteriorated climate, two of which particularly evident and conspicuous characterised by the wide diffusion of the Ephedra.