Investigating energy balance and carbon footprint in saffron cultivation – a case study in Iran

Saffron is one of the most expensive agricultural crops in the world which needs to be clearly monitored in the view of energy balance and carbon footprint in the production stage. Iran is the leading countries in saffron production and now accounts for approximately 60% of the world total production. As the biggest producer of saffron, analyzing the energy and carbon balance would help to produce this crop more economically and environmentally friendly. In the present study, the saffron cultivation in Southern Khorasan, a province in the east of Iran was taken into consideration and this cultivation was evaluated in terms of energy balance and carbon footprint. The evaluation was performed based on the data derived from whole life cycle of this crop i.e., a 6 year period. The assessment of energy balance demonstrated that on average, the total input energy consumed was 99,236 MJ ha⁻¹. More specifically, the average of energy indices i.e. energy ratio, energy productivity, and net energy were calculated 0.0044, 0.0003 kg MJ⁻¹, and −98,818.5 MJ ha⁻¹, respectively. The results clearly revealed that Nitrogen based fertilizers, farmyard manure and Phosphor based fertilizers dominated the total energy consumption meaning that their consumption management need to be given a priority. The total greenhouse gas emissions in saffron production was calculated on 10,897 kg CO_2eq ha⁻¹ which showed a high degree of mismanagement in farm practices in the region meaning that without considerable reduction in saffron yield energy saving can be achieved.