Life cycle assessment (LCA) in crop production, case study: apples and grapes

Life Cycle Assessment (LCA) is a comprehensive assessment method that allows the estimation of cumulative environmental impacts from all life cycle stages of an activity. The destructive effects of agricultural development on the environment,environment are of a great importance. Insufficient attention to the pattern of consumption of production inputs in the agricultural sector as the main consumer of water in Iran can exacerbate environmental challenges. Misuse of inputs such as chemical fertilizers in order to increase agricultural productivity, pollutes water and soil resources. On the other hand, in environmental impact assessment studies, crops have received much more attention than horticultural crops, while horticultural crops have generally more water requirements.

As Iran as a semi-arid country is facing a water shortage crisis, in this study the evaluation of agricultural activities and grape and apple crops using ecological footprint method and life cycle assessment (LCA) as suitable solution for future plans are considered to reduce environmental pressures and meet consumption needs in order to achieve sustainable development goals. Input generation information of Simapro 9.0.0.49 software is used to analyze the environmental impact. Calculations were performed for a functional unit if 1 kg. Life cycle impact was assessed and categorized into 6 impact groups: cumulative energy demand, ecological footprint, water footprint, global warming potential, greenhouse gas protocol and Eco-indicator (including greenhouse gases, ozone layer, acidification, eutrophication, heavy metals, pesticide and energy resources).

According to the results, the water scarcity index based on water footprint for apples is about 1.7 times that of grapes. The ecological footprint of carbon in oxide and surface occupation for apple crop is 1.3 and 4.65 times that of grape crop, respectively. The potential for global warming, based on the accumulation of carbon dioxide, methane, and nitrogen oxides, is not significantly different between the two crops, and its value for apples is 1.3 times that of grapes. Greenhouse gas emissions and pesticide damages are 1.29 and 4.24 higher for apples, respectively, than for grapes. Consumption of energy sources for one functional unit of two apple and grape crops is 10.1 and 9.13 MJ LHV, respectively.