SUMMARY
To evaluate environmental sustainability of complex systems, such as agricultural cultivation, it is necessary to adopt a systemic approach that considers all mass and energy flows that drive processes and that interlace, amplify, and influence each other. Emergy analysis, a thermodynamic-ecological methodology developed by Odum (1988), produces powerful indicators to evaluate process efficiency and to assess long-term sustainability. We performed a comparison among three cherry crops with different cultivation methods (traditional, biological and integrated) employing different inputs (natural and non-natural), in order to understand how agricultural systems should be developed in order to be economically successful with respect to the environment. Traditional methods using high quantities of non-natural inputs demonstrated unsustainability, while the integrated method of natural and purchased inputs turned out to be the best. The emergy approach demonstrated a powerful methodology to assess sustainability, and the indications obtained for cherry crops could be extrapolated to other types of cultivation.