Life cycle assessment of organic and mineral fertilizers in a crop sequence of cauliflower and tomato

This study presents a life cycle assessment of a crop sequence of cauliflower and tomato that is subjected to three different fertilization treatments; the crops were cultivated in a Mediterranean region. The main objective of this study is the assessment of organic and mineral fertilizers that are applied to a crop sequence of tomato and cauliflower. Two allocation procedures that are based on the crop cultivation time and the degree of nitrogen mineralization were implemented to allocate the compost burden to the crops. The results indicated that the crops fertilized with home compost achieved the best environmental performance in all impact categories, regardless of the allocation methods, with the exception of marine eutrophication and terrestrial acidification. The comparison of the impact (kg eq. of pollutant/day) on the entire horticultural cycle with the individual crops indicates that cycle yielded the least amount of impact among the assessed categories. The crops that were fertilized with the home compost using the allocation method, which is based on the degree of nitrogen in the soil, exhibited the least impact value among all categories. However, the allocation procedure based on the cultivation duration was considered to be the better attributional method given the high degree of uncertainty in the nitrogen degradation. This uncertainty is related to the complex interactions among the variables to metabolize the following nutrients (i.e., nitrogen) of fertilizers: variety of crops, crop management, soil type, weather conditions and fertilizer.