Impact of climate change on groundwater and the extinction of ancient \u201cFoggara\u201d and springs systems in arid lands in North Africa: a case study in Gafsa basin (Central of Tunisia)

Abstract

The rising increase in groundwater abstraction to serve the industrial sector and to fulfill the agricultural and domestic needs, coupled with severe drought periods during the past decades, leads to a growing deficit of water. The drawdown of piezometric levels and progressing degradation of water quality are the main consequences of such intensive exploitation. In this connection, the present study emphasizes the major effects of groundwater resource overexploitation in Southern Tunisia, and it evaluates its impacts on the ancient mkayel “Foggara” system. Although it is crucial role in various aspects of modern society, especially in Gafsa basin (“El Guettar region”, central of Tunisia), this system is facing an increasing abandonment with the introduction of new technologies in response to the irrational exploitation. The mkayel are particularly susceptible to impairment by groundwater withdrawals with modern wells and pumps. In arid regions, the proper conservation and maintenance of the mkayel systems constitute promising alternatives for sustainable water management and for supporting economic development. In the past few decades, we witness a gradual disappearance of these galleries by an average loss of a dozen of mkayels per year for over half of a century expressed by a significant drop in the discharge of the 800 functional mkayels, enough to irrigate 450 ha, from 1000 l/s in 1900, 200 l/s in 1960, and 5 l/s in 1975 to 0 l/s in 2011 related to technical, social, and environmental causes. Despite the continuous extinction of mkayels, many Arabic countries still consider it as an important system of water transfer.