Published online by Cambridge University Press: 03 March 2015
Desert oases are undergoing rapid changes in response to environmental, economic and social pressures. The Wādī al-Hayāt, in the Libyan Fazzān, illustrates these changes and exemplifies some of the processes at work. Human activity in the area is dependent on groundwater extraction. Introduction of mechanical pumps and modern irrigation technology has enabled significant expansion of irrigated area, but environmental problems have arisen as a result. Geoarchaeological studies have demonstrated that groundwater levels have fallen over the latter half of the Holocene. Large decreases have occurred since 1970 as a result of abstraction for agricultural, domestic and industrial use. This study uses aerial photographs from 1958 and Landsat imagery from 1987, 1999 and 2000 to map changes in the area under irrigation in the Wādī al-Hayāt. We find a general southwards migration of oasis agriculture within the Wādī, as vegetation has died in the northern part of the Wādī and irrigation extended to the south. A significant amount of inter-annual change in vegetation cover is identified, indicating the need to account for seasonal cropping practices when monitoring for longer-term changes.