The evolution of Saharan dust input on Lanzarote (Canary Islands) — influenced by human activity in the Northwest Sahara during the early Holocene?

Abstract

An overall Holocene increase of Saharan dust input to the Canary Islands and to the North Canary Basin is accompanied by a strong coarsening of Saharan dust in loess-like sediments deposited on Lanzarote from ~7—8 ka. No similar coarsening events are indicated in investigations of the sedimentological record for the last 180 ka, a period showing several dramatic climate changes. Therefore a mobilisation of Holocene dust by anthropogenic activity in the northwest Sahara east of the Canary Islands is assumed. Although scarce archaeological data from the coastal area of that region does not point to strong anthropogenic activity during the early Holocene, a high density of unexplored archaeological remains is reported from the coastal hinterlands in the Western Sahara. Thus, the hypothesis of early anthropogenic activity cannot be excluded.