As a result of climate change (CC), French agriculture is already experiencing, and will continue to experience in the near future, situations of greater water stress. Increasing the resilience of agricultural systems, i.e. the ability of a system to maintain its current state but also its capacity to adapt in the face of systemic change, is one of the major levers for mitigating the effects of CC on agriculture. Irrigation, which is expanding in France, is destined to play a central and problematic role: it enables farms to be less economically vulnerable to drought episodes in the short term. In the long term, however, it could prove to be a maladaptation, creating new vulnerabilities on several scales. At farm level, it increases the dependence of agricultural production on water resources and may discourage the adoption of agro-ecological practices to adapt to CC. On a territorial scale, it may increase water consumption for agriculture in a context of increasing water stress due to CC. The aim of this thesis is therefore to understand how the expansion of irrigation in France affects the resilience of agricultural systems at these two scales, and which forms of regulation are most effective in ensuring sustainable irrigation and fair sharing of water resources. We'll be looking to see how irrigation affects the economic but also how it modifies (or not) agronomic practices. Finally, in two Mediterranean regions, we will examine the impact of irrigation on the dynamics of water resource sharing and the sustainability of water resource management.

Key words :  Irrigation, agroecology, adaptation, climate change, resilience