THE VEGETATIONAL HISTORY OF THE NORTHERN APENNINES, ITALY - INFORMATION FROM 3 NEW SEQUENCES AND A REVIEW OF REGIONAL VEGETATIONAL CHANGE

The results of pollen analysis and radiocarbon dating are presented fr om three northern Apennine sequences; Lago Padule in northern Tuscany and Lago Pratignano and Ospitale in the Emilia-Romagnan Apennines. Thi s is the first detailed pollen stratigraphic information from sites in Emilia-Romagna and north Tuscany and extends eastwards the area from which information on vegetational history is available. The sequence f rom Lago Padule is one of the most complete Holocene records known fro m the northern Apennine region. Lago Pratignano has the deepest sequen ce of organic sediments (1544 cm) and the fastest rates of sediment ac cumulation (up to 28 cm per 100 years) providing the highest resolutio n record for the mid to late Holocene periods in the region. High rate s of sedimentation have also occurred at Ospitale where organic sedime nts are 780 cm deep and began to form at approximately 5500 BP. The re cord from Lago Padule is compared with Holocene records from two nearb y sites and a series of Regional Pollen Assemblage Zones is defined fo r the eastern area of the northern Apennines. The main features of veg etational change identified are: (i) a 'pioneer' phase of rapid forest development during the early Holocene followed by the establishment o f an upper forest belt dominated by Abies, and a belt of mixed deciduo us forest at lower altitudes; (ii) the appearance and rapid expansion of Fagus between approximately 5200 BP and 2900 BP forming a mixed Abi es-Fagus association in the upper forest belt; and (iii) the overall r eduction of forest cover, and dominance of Fagus in the arboreal veget ation from around 2900 sp. The scheme of Regional PAZs for the eastern area is used as a framework for the review of pollen stratigraphic in formation and radiocarbon dates from other sites in the northern Apenn ine region. Characteristics of pollen records which can be identified in sequences from across the region are identified and the chronology of similar changes in pollen stratigraphy is examined. The scheme of f our regional PAZs for the Holocene period is shown to be valid for the entire northern Apennine region. The examination of a series of polle n records shows that Fagus appeared earlier in the western than the ea stern part of the region during the mid Holocene and became dominant i n the northern Apennine forests post 3000 sp. The impact of anthropoge nic activity and climatic change on the spread and development of Fagu s are discussed. The palynological evidence which is now available fro m the northern Apennines is compared with information for the region s hown in the 'European pollen maps' of Huntley & Birks (1983). This stu dy provides an updated review of the representation of different tree taxa in Holocene pollen records from the northern Apennines and illust rates the role of the northern Apennines as a refugium for trees durin g the Wurmian Lateglacial.