Abstract EN:

This thesis analyses the impact of irrigation on agricultural development in tunisia. It shows that if the irrigated crops sector has benefited from considerable material, financial, institutional and human means, it has not resulted in the development of the agricultural sector that was expected. This is notably true for public irrigation installations (ppi) created at great expense by the state but developed individually by the "fellahs". This situation can be explained by a partial development of irrigable land and a weak consumption of water available in dams and pumping stations. This thesis suggests a ppi problematic which shows that the state's technological approach does not coincide with the rationality of farmers involved in the tunisian hydro-agricultural project. In fact, the implementation of an irrigation policy and its success involves real changes in production systems, and even in the lifestyles of the "fellahs". However, these changes involve technical risks which the "fellahs" of the northern regions have not yet learned to manage, as well as economic and financial uncertainties for which they are not yet prepared. In this region of rainfed agriculture, conversion to irrigated systems appears to be slow, incomplete and highly variable, resulting in a real mosaic of production systems. This reality is far from corresponding to the technico-economic patterns promoted by extension workers but reflects the heterogeneity of the "fellah's" responses to the type of innovation which large irrigation systems constitue within an environment where water is not always a limiting factor for cereal production.