Late-Glacial and Holocene vegetation history of Pavullo nel Frignano (Northern Apennines, Italy)

Abstract

Until recently, pollen-stratigraphic research in the Northern Apennines (Northern Italy) provided only generalized pollen diagrams that lacked reliable chronologies, and few records provided complete and detailed postglacial sequences equipped with radiocarbon dates. We present a new Late-Glacial and Holocene pollen sequence from Pavullo nel Frignano in the Emilian Apennines (Modena, Italy). The chronology relies on AMS-radiocarbon-dated samples of terrestrial plant origin. Our pollen record suggests that open Late-Glacial Pinus and Juniperus dominated woodlands were established at the site before 14,000 cal. BP. Thermophilous trees such as Quercus, Ulmus, and Tilia as well as Abies alba expanded already during the Late-Glacial (ca. 14,000–13,000 cal. BP), but did not form closed forests. After climate cooling of the Younger Dryas A. alba re-expanded at the onset of the Holocene at ca. 11,500 cal. BP and remained the dominant species until at ca. 6000–5500 cal. BP. The decline of A. alba was associated with a marked opening of forests, and the expansion of deciduous trees such as Fagus and Quercus. Vegetational composition did not change substantially during the past 5000 years, and cultivated tree taxa such as Juglans and Castanea played only a transient or marginal role. Although the vegetation history of Pavullo is consistent with previous investigations in the study area, comparison is hampered by the absence of other records from the same vegetational (colline) belt. Our pollen-inferred human-impact history is in agreement with archaeological evidence. In addition, our results suggest a rather close link between vegetational change in the Northern Apennines and the Southern Alps. Common features between these two climatically-similar regions are the initial expansion of thermophilous trees and Abies alba at ca. 13,000 cal. BP, the mid-Holocene collapse of A. alba (probably as a consequence of human disturbance) as well as the subsequent expansions of Quercus and Fagus.