A review of the rise and fall of ancient desert runoff agriculture in the Negev Highlands - A model for the southern Levant deserts

The rise and fall of desert agriculture in the southern Levant has been debated among scholars for the last 200 years, in the chronological, the socio-political and the environmental context. Based on c. 31 OSL ages of sediments from agricultural terraces in various sites in the Negev Highlands, the main phase of ancient desert agriculture was dated to between the 3 ^rd -4th centuries CE and the 10 ^th -11th centuries CE (Avni et al., 2013). Within this longue durée process of agricultural activities, no significant environmental or climatic change was observed coinciding with the Byzantine- Islamic transition in the 7th century CE. Our research, which focused on the natural processes that influenced the rise and fall of the Negev desert agriculture, found that the agricultural installations were sustainable for at least 700 years and parts of these agricultural constructions are still in use today. This long period of usage is a clear indication of their robust design and their good adaptation to the desert environment, despite possible short-term climatic fluctuations. However, continuous flooding, gulling, soil erosion and siltation required constant maintenance of agricultural systems by the local farmers. In addition, the political and economic changes that followed the Byzantine-Islamic transition triggered a gradual decrease in the economic value of the products of desert agriculture, followed by a disruption of the social-political balance between local farmers and herders. These made the desert runoff agriculture less viable, leading to its final demise after the 10th century CE. Therefore, a direct link between the rise and fall of desert runoff agriculture and the claimed climatic changes in the southern Levant seems unlikely.