Modern agricultural intensification is one of the biggest causes of damage to archaeological sites in the al-Jufra. Table 1 shows how the modern cultivated area has increased since the 1970s, encroaching on areas of ancient activity. Cultivation was mapped using Landsat images to generate unsupervised classifications for the period 1975–2011.
Table 1: Vegetated areas (ha) calculated based on a SAVI (Soil Adjusted Vegetation Index) algorithm applied to multispectral Landsat images.
||Vegetated area (ha)
||increase from previous image
|| 60 %
|| 16 %
|| 17 %
A large area of nineteen channels south of Waddan can still be identified in modern satellite imagery, some ending in a small group of buildings and gardens, showing where the area of irrigation and settlement was located (see Figure 2). These flow northwards, extracting from a location of more accessible groundwater, and following the natural gradient of the landscape. Some of them have more than one branch, suggesting that attempts were made to increase the amount of flow into the main channel. The system is likely evidence of some of the earliest oasis settlement and agriculture in the central Sahara. However, these are imminently at risk of destruction because of their proximity to modern cultivation. Fields immediately to the north have caused the majority of the ancient fields and settlements associated with the foggaras to be destroyed. Most recently, a layout of new field boundaries representing a significant new agricultural area has been constructed over the channels themselves (Figure 3). Once the new fields are brought into cultivation, they will be levelled and the foggaras removed.New fields have damaged areas of ancient cultivation and settlement, removing many traces of foggara irrigation systems. Dating to the 1st–5th centuries AD, foggaras are subterranean canals which collect groundwater (or in some cases spring water) and transport it to the fields. They are identifiable in satellite images as lines of spoil mounds which are the visible part of the access shafts above the underground tunnel. An area of foggaras south of Hun could be mapped using a 1972 Corona image, but only a few short segments of the tunnels now remain.