The history of Holocene soil erosion in the Phlious Basin, NE Peloponnese, Greece, based on optical dating

Abstract

Anthropogenic induced soil erosion has occurred in the Mediterranean during historic and pre historic times, but precise timeframes for periods of past soil erosion are largely missing due to the lack of datable material and suitable dating methods. In this study, optical dating of colluvial sediments from the Phlious Basin, NE Peloponnese, Greece, was applied. The results show that soil erosion derived colluvium formed under a Mediterranean type climate can be successfully dated by optical stimulated luminescence (OSL), and a high-resolution chronology of Holocene soil erosion could be established. Colluvial formation occurred in the early Holocene, but increased distinctly in the seventh millennium, parallel with the onset of the Neolithic (the start of farming activities). Other periods of strong colluviation are the Middle and Late Bronze Age (second millennium), the Roman period (first century to sixth century) and the period since the sixteenth century. Rates of reduced colluviation occurred during the Chalcolithic to the Early Bronze Age (4500–2050 a) and the Early Iron Age (1065–725 a). Based on thin section analysis of the colluvial sediments, no traces of in-situ soil formation and thus no periods of landscape stability were detected for the Holocene. Results show that human activity is the dominant factor for Holocene landscape changes in the area studied.