life cycle assessment of paste production (case study: alborz province)

agriculture (mechanization), food industry and environment are the concepts that cannot be surveyed separately (because of their interaction). present research aimed to study tomato paste production by applying life cycle assessment. two functional unit of kg co2-eq/ kg tomato and kg co2-eq / kg paste was used. data were collected from one paste factory in alborz province and open-field tomato farms in alborz and east azerbaijan provinces. in order to evaluate the greenhouse gas effect, carbon footprint index was used. the average carbon foot print value of the paste production was 3.02 kg co2-eq / kg paste which the tomato production had the highest share in total emission. also, carbon foot print value of tomato production was 0.22 kg co2-eq/ kg tomato and the highest share belonged to material and energy use emission category. in this category, the most important inputs were electricity and chemical fertilizer. comparison of carbon foot print value between alborz and east azerbaijan provinces and between conventional and modern irrigation systems showed that the carbon foot print value in modern irrigation system in alborz province is less than the other ones. regression models between carbon footprint index and tomato cultivation area and yield was developed.