Life cycle assessment of soilless systems: a systematic literature review

Soilless systems imply the use of substrates instead of soil and delivering nutrients through liquid mixtures, leading to water and fertilizer reduction. In addition, being in a controlled-environment, harmful substances like pesticides are minimized. However, the complexity of these systems requires comprehensive assessments to avoid unintended negative environmental impacts. By conducting a systematic review of 46 Life Cycle Assessment (LCA) articles on soilless systems, this study examines methodological choices and assumptions made by LCA practitioners, shedding light on the strengths and limitations of current practices. Results show that mass-re lated functional units and cradle-to-gate system boundaries are predomi nant in the assessed studies, reflecting a focus on production stage, while distribution and consumption phases often receive less attention. Environ mental hotspots identified include energy consumption for irrigation and heating, nutrient solution, and structural materials. Notably, the impacts associated with macro-nutrients, as well as steel, aluminum, polyethylene from greenhouse structure, and non-renewable energy sources, have been found to be significant in terms of environmental impacts. The use of re cycled materials for infrastructure, the integration of renewable energy sources such as wind power or photovoltaic system, and the optimization of fertilizer or use of biofertilizer, may minimize the environmental impacts of soilless systems. By adopting a life cycle perspective and incorporating sustainable practices, soilless systems can play a vital role in achieving en vironmentally friendly and resource-efficient agriculture.