The Late Desertification In The Central Sahara: Rise And Decline Of The Kingdom Of Garamantes
by
Mauro Cremaschi
CIRSA , CNR IDAP , Dipartimento di Scienze della Terra - Università di Milano Milan - Italy
Coauthors: Mario Liverani, Savino Di Lernia, Manuela Pelfini, Maurizio Santilli (CIRSA, CNR IDAP, Dipartimento di Scienze della Terra - Università di Milano Milan - Italy, CIRSA, Dipartimento di Scienze dell'Antichità - Università di Roma 'La Sapienza' - Roma - Italy)

The largest part of the central Sahara dried out at about 5000 years bp as an effect of the withdrawal of the SW monsoons to the present position . However, several areas escaped desertification for millennia, because of short periods of enhanced rainfall and due to the existence of hydrological reservoirs, not completely exhausted by increasing droughts. In these areas - the oases - thank to sustainable life conditions, Late Pastoral communities concentrated, giving rise to incipient forms of sedentism and to first examples of internal social hierarchy. The case of the kingdom of Garamantes in the palaeoasis of the wadi Tanezzuft is discussed on the base of recently discovered geological evidence and the dendroclimatical curve of the Cupressus dupreziana. Intensified rainfall during the ca. 2450 - 2250 bp interval can be correlated with the formative phase of the Garamantian polity. More interestingly, the progressive decline of rainfall in the ca. 2250 - 1950 bp period corresponds to a period when the Garamantian kingdom tried to react against increased aridity by setting up a new organisation and strategy, based on intensified horticulture, establishment of walled citadels, management and strategy of the long distance trade across the Sahara (with use of dromedaries). The final collapse of the Garamantian kingdom at 1600 years bp is coincident with the onset of hyperarid conditions (sharp decrease in tree ring growth in the dendroclimatical curve, aggradation of sand dunes ) which can considered the final outcome of desertification.

Date received: May 21, 2002

Copyright © 2002 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # caji-30.