Environmental impacts assessment of saffron agroecosystems using life cycle assessment methodology: (Case study: Torbat-e Heydarieh and Ghaen counties)

In order to assess the environmental impacts of saffron agroecosystems during the first to seventh years in the two counties of Ghaen and Torbat-e Heydariyeh as two important poles of saffron production at different levels of inputs and livestock manure (less than 100, 100-150 and more than 150 t.ha-1), a study by using life cycle assessment (LCA) was conducted in 2015. Based on ISO14044 method, LCA was computed in four steps including goal definition and scoping, inventory analysis, life cycle impact assessment (such as global warming, terrestrial eutrophication, aquatic eutrophication and acidification categories) and integration & interpretation. Functional unit was considered as one ton flower. The results showed that consumption of inputs such as fuel, livestock manure and chemical fertilizer in Torbat-e Heydariyeh was higher than Ghaen. The highest flower yield in Ghaen and Torbat-e Heydariyeh counties were obtained at the lowest levels of livestock manure (with 1.47 and 1.66 t.ha-1, respectively). The maximum value of aquatic eutrophication potential in Ghaen and Torbat-e Heydariyeh counties were related to the highest livestock manure level with 4.861 and 10.983 PO4 equiv./t flower, respectively. The highest of environmental indicator in the two counties of Ghaen and Torbat-e-Heydariyeh were calculated for the maximum livestock manure with 1.34 and 3.18 Ecox per one ton of flower. Considering the high levels of environmental impact of saffron agroecosystems especially in Torbat-e-Heydarieh, it is suggested to apply strategies such as intercropping, minimum tillage, and optimum levels of organic fertilizers.