The record of land use change and soil erosion in the late Holocene sediments of the Petit Lac d'Annecy,eastern France

Pollen, chemical and magnetic analysis of a 6 m core from the Petit Lac d'Annecy provides a record of land use change and soil erosion spanning the last 2000 years. Variations in the magnetic properties of the sediments, especially above 3 m in the core, can be linked to the history of soil inwash over the last 1000 years. These changes, together with parallel ones in element concentrations and pollen frequencies (both concentrations and percentages), can be interpreted by reference to the land use history in the catchment during medieval and post-medieval times. Peak deforestation and human impact on vegetation and soils is recorded from the eleventh to fourteenth centuries and again during the eighteenth century. The present study suggests that future detailed analyses of the laminated sediments of the lake could provide a precisely datable fine resolution environmental history of the lake and its drainage basin.