Legume–Durum Wheat Cropping Systems for Sustainable Agriculture: A Life Cycle Assessment Systematic Literature Review

Global sustainability challenges call for assessing the environmental impacts of agricultural production systems, which are crucial to meeting the nutritional demands of a growing global population. This study uses the PRISMA model and a checklist to provide a systematic literature review of LCA studies on durum wheat and legume cultivation; it highlights the impacts of monoculture cultivation with crop rotation on key environmental indicators. An analysis was conducted to examine the environmental burdens of these crops under conventional and organic systems and explored how using different functional units (mass- or area-based) influences the environmental outcomes. The results reveal that integrating legumes into crop rotations significantly enhances environmental sustainability by reducing reliance on synthetic nitrogen fertilizers through biological nitrogen fixation, resulting in substantial environmental benefits, reaching a reduction in GWP from 6 to 45% compared to monoculture durum wheat cultivation. Conventional agriculture achieves higher crop yields; however, its reliance on chemical inputs and substantial energy consumption results in greater overall environmental impact. Conversely, while organic farming has a lower impact per unit of land, its lower productivity results in higher emissions per unit of output.