Evaluation of Carbon Footprint for Saffron Production Systems in Khorasan Provinces

Carbon footprint (CF) is the total amount of greenhouse gas emissions per unit of farmlands. Since the used inputs have an important role in greenhouse gas emissions, CF as an ecological indicator have been extensively applied for assessing the environmental externalities in agroecosystems. This study was conducted to estimate the CF and carbon efficiency (CE) of saffron production systems in North Khorasan, Razavi Khorasan and South Khorasan provinces. Also, life cycle assessment analysis is calculated for quantifying the impact of saffron farming activity on the environment. Studied indices were global warming potential (GWP), acidification potential )AP) and eutrophication potential in terrestrial (UPT) and aquatic (UPA) sub-categories, N2Odirect, N2Oindirect, N2O emissions affected as volatilization and leaching, carbon inputs (Ci), carbon outputs (Co), CF and CE. The results revealed that the lowest GWP for saffron production systems was related to south Khorasan with 339.43 kg CO2 equiv./ one kg flower yield. The minimum environmental index (EcoX) was recorded for south Khorasan (0.039 EcoX/ one kg flower yield). N2O emissions in South Khorasan, Razavi Khorasan and North Khorasan provinces were estimated with 95974.51, 199674.4 and 344723 kg N2O per one ha, respectively. The largest N2O emissions affected as leaching and volatilization were calculated for North Khorasan province (with 1.21 and 24.23 kg N2O per one ha, respectively). The maximum Ci and Co were related to North Khorasan province with 117986.52 and 15135.56 kg C per one ha, respectively. The largest CF and CE were computed for North Khorasan and south Khorasan provinces with 7.8 and 0.18, respectively. It concluded that adoption on conservation and reduced tillages, N2- fixing pulses, cover crops and green manures in rotations with saffron and increased nitrogen use efficiency as ecological approaches can optimize the system performance while reducing environmental externalities and the carbon footprint of the crop cultivation. So, with relevant agro-environmental policies in saffron production systems along with the adoption of improved agronomical practices increasing flower yield with no cost the environment can be achieved effectively, efficiently and economically.