Etaghas: an unprecedented evidence for agricultural landuse in the hyperarid central Sahara

Rainfall in the hyperarid Central Sahara is unpredictable; but occasionally it may originate ephemeral ponds, which can stand for several weeks (e.g. Fantoli 1937, Davies and Gasse 1988; di Lernia et al. 2012). In the Tadrart Acacus massif (SW Libya), for instance, recent ethnographic interviews have disclosed the complexity of the social perception of rainfall and scarcity of water availability, highlighting the existence of unexpected subsistence strategies related to the systematic exploitation of limited water resources and deeply rooted in the local historical and possibly archaeological background (di Lernia et al., 2012). Among the many abilities accomplished by the local Tuareg people to preserve surface water and maximise benefits coming from occasional rainfalls, we discovered the possibility to cultivate small patches of the desert after the main rainfalls. This form of traditional cultivation, up to now only occasionally reported for a few Tuareg groups in Mali and Algeria (Nicolaisen and Nicolaisen 1997), is represented by the exploitation of these temporary ponds, locally called etaghas (Bourbon del Monte Santa Maria 1912). ... The etaghas are well-defined areas whose physiographic features make recession cultivation possible and allow people living in the Tadrart Acacus massif to obtain directly, today as in the past, occasional yields (di Lernia et al. 2012). Radiocarbon dating and the occurrence of a complex archaeological landscape surrounding the etaghas suggest that this subsistence practice dates back at least to early historical times. Finally, in a cultural landscape dominated by the oasis-desert vs. agriculture/pastoralism dichotomy, this kind of landuse offers new perspective in the interpretation of the Pastoral-Neolithic exploitation of the central Sahara.