Life cycle environmental impacts of saffron production in Iran

Saffron is regarded as an important crop in Iranian agricultural economics that needs to be investigated to produce the environmentally friendlier product. In the present study, saffron production as an important agricultural production system in Iran was evaluated thoroughly from an environmental point of view. Data were collected from saffron farmers in Southern Khorasan province of the country with face-to-face questionnaire method during cropping period of 2013-2014. The system boundary was considered from the production of raw input materials to the harvested saffron. In order to identify the main hotspot during cultivation, impact categories were considered using CML methodology and cumulative exergy demand (CExD) indicator. Based on the results, chemical fertilizers N and P were the main hotspots in abiotic depletion (AD), acidification (AC), global warming (GWP), and photochemical oxidation (PO) impact categories, while diesel fuel was the main hotspot in fresh water aquatic ecotoxicity (FE), marine aquatic ecotoxicity (ME), and terrestrial ecotoxicity (TE). Direct emission from diesel fuel combustion (saffron) was the main hotspot only in human toxicity (HT). The small farms had the highest amounts of AD, AC, EP, GWP, and PO indicators in comparison with the medium and large farms. Total CExD indicator for production of 1 kg saffron was 1894.23 MJ eq. Totally, large farms (bigger than 1 ha) had better environmental performance considering all the impact categories.