Rise and Fall of an Egyptian Oasis: Artesian Flow, Irrigation Soils, and Historical Agricultural Development in El‐Deir, Kharga Depression, Western Desert of Egypt

Abstract

International audienceThe present study examines the geoarchaeological history of an oasis in Kharga Depression in central Egypt. El-Deir is renowned for its Ptolemaic temple and Roman fortress on the road from former Hibis (Kharga) to the Nile Valley. During the survey, spring mounds and irrigation soils belonging to an ancient agricultural zone were discovered, and further documented by ceramics found on the site. Our methodology combines the geomorphological interpretation of landforms (especially yardangs) with ceramics and 14C-dated charcoal to distinguish and date former agricultural areas in El-Deir. The results show that the oasis experienced several phases of soil accretion and destruction through time. Playa sediments were deposited in the humid early Holocene and severely eroded by deflation before the onset of irrigated agriculture between Pharaonic and Persian times. Very fast vertical soil accretion occurred in the Ptolemaic period, but irrigation soils were later destroyed during the Roman period by a combination of wind deflation and flash floods (second to fourth century A.D.), suggesting a period of climate instability. The case of El-Deir invites reevaluation of constructive agencies for the development of irrigated land and destructive agencies as limiting factors for the sustainability of agricultural practices in late antiquity

Holocene large lake development and desiccation: Changing habitats in the Kharga Basin of the Egyptian Sahara

“…Many of these residues appear to be in the relicts of small drainage basins within the shores of an extensive earlier lake for example, the site named Treewater. At Qasr al‐Deir, Tallet et al (2012) and Bravard, Mostafa, Cargia, et al (2016) describe yardangs derived from spring mound deposits that incorporate Roman pottery. In the Dakhla Oasis, Bravard, Mostafa, Davoli, et al (2016) also described spring mounds that also captured sediment, in that case, accumulated from irrigation soils.…”

Cottoning on to Cotton (Gossypium spp.) in Arabia and Africa During Antiquity

“…In Dakhlah oasis, irrigation systems composed of wells and canals spread during the Ptolemaic period, before the visible emergence of cotton. In the Kharga oasis, a complex irrigation system was probably established in the northern region, at El-Deir, and generalised in the southern area in the 5 th century BC, which was further expanded and reconfigured during the Roman period (Chauveau 2005; Gonon et al 2005;Bravard et al 2016). At Madâ'in Sâlih, about one hundred wells were built during the Nabataean period (1 st century BC-1 st century AD) (Courbon 2008), before the arrival of cotton.…”

Mid‐Holocene environmental change and human occupation at Sai Island, Northern Sudan

“…Generally, as conditions became more arid and both surface and groundwater availability more uncertain, settlement in northern Africa concentrated in areas of more reliable water access. Reliable sources primarily took the form of artesian springs and associated playas in oasis settings (Bravard et al, 2016;Nicoll, 2001Nicoll, , 2004 as well as the Nile River and its regular seasonal floods (Williams, 2019). In areas with less permanent water sources, the movement of the ITCZ and the summer monsoon generally determined rainfall availability during the Holocene (Kropelin et al, 2008;Wendorf, Karlen, & Schild, 2007).…”