A modeling framework to optimize asparagus growth and management

Crop production faces increasing pressure from population growth, rising food demand, climate change, and the need to reduce the environmental impact of agricultural practices. Applying ecological principles to the design and management of agricultural systems has contributed to the development of agroecology, a rapidly growing field with considerable potential to support more sustainable crop production. Mathematical models describing crop development and its interactions with environmental and management conditions can play a key role in addressing these challenges. This Master's thesis develops original modeling approaches for the optimal control of agronomic practices for Asparagus officinalis. Because asparagus is a perennial crop, management decisions must be considered over multi-year horizons while accounting for variations in climatic conditions and market demand. The thesis is organized into three chapters. The first chapter introduces a novel model of asparagus phenology and uses it to characterize the climatic suitability of asparagus cultivation in France under future climate scenarios. The second chapter presents a nonlinear, discrete-time, time-varying model describing white asparagus growth and reserve dynamics. The third chapter formulates optimal control problems addressing two important decisions faced by asparagus producers: determining the optimal time to end harvesting within a given season to maximize yield over several seasons, and regulating soil temperature through the use of plastic mulches.