Résumé
In the governorate of Kebili in southern Tunisia, irrigated areas have developed considerably over the last 30 years. The traditional oasis system, based on three-level cultivation and complementarity between agriculture and livestock farming, has been undermined. Many farmers have limited their activities to date production, both in traditional oases and in the new irrigated areas. This article measures the influence of water availability and various factors related to farmers' orientations on their decision to implement ecologically intensive farming practices. The main practices studied are the cultivation of fruit trees under palm trees and the use of manure as a fertiliser. Fifty farmers, who obtained the management of agricultural land in the municipality of Jemna at the beginning of the 2000s, were surveyed. Water availability is a major factor facilitating ecologically intensive practices. These practices are also favoured by the fact that family income is primarily derived from the plot in the study area. Another important factor is the interest in sustainable farm management - as opposed to management aimed at short-term profitability. There are farmers in Kebili governorate who want to make farming an economic and a life project and who are willing to implement ecologically intensive farming practices. The decline in agrobiodiversity observed in the traditional oases of southern Tunisia is therefore not inevitable, if access to water is improved and if life projects based on agriculture are made more feasible.