Evaluation of environmental impacts for saffron agroecosystems of Khorasan based on nitrogen fertilizer by using Life Cycle Assessment (LCA)

Life cycle assessment (LCA) is a methodology to assess all environmental impacts associated within a product by a accounting and evaluating its resource consumption and emission to environment. This study evaluated the environmental impacts of saffron agroecosystems of Khorasan based on nitrogen levels by using life cycle assessment (LCA) methodology, mean corm weight and consumed inputs in saffron agroecosystems of Khorasan per one ha were defined during years of 1999 to 2013. Four steps including goal definition and scoping (D & S), inventory analysis (IA), life cycle impact assessment (LCIA) and integration &interpretation (I & I) were considered based on ISO (International Organization for Standardization) 14040 methods. Acidification, aquatic and terrestrial eutrophication and global warming were considered as three important impact categories. Functional unit of saffron agroecosystems was considered as one tone corm. The results showed that by increasing in nitrogen fertilizer level from 200 to more than 350 kg.ha-1 acidification and aquatic and terrestrial eutrophication impact categories enhanced up to 37, 36 and 37%, respectively. The highest global warming potential was computed with 1128.17 CO2 equiv./t corm for 350 kg N ha-1. The maximum eco-Index for saffron agroecosystems of Khorasan were calculated in 350 kg N ha-1 with 0.62 PO4 equiv./t corm and 0.12 CO2 equiv./t corm, respectively. Therefore, it can be concluded that applying of organic principles such as reduced tillage and organic fertilizer as sustainable approaches were considered for management of saffron agroecosystems.