Iranian Journal of Applied Ecology

In order to evaluate life cycle assessment (LCA) for rice agroecosystems based on mean of nitrogen fertilizer levels (less than 190, 190-200, 200-210, 210-220 and more than 220 kg N ha) during 1999-2012, an experiment was conducted. Four steps includung goal definition and scoping, inventory analysis, life cycle impact assessment and integration and interpretation were computed. Functional unit was considered as one tone paddy. Impact categories were acidification, eutrophication in aquatic and tresstrial ecosystems and global warming. The results showed that the highest paddy yield was obtained 5.35 t.ha^-1 in 190-200 kg N ha. The maximum aquatic eutrophication potential was computed for more than 220 kg N ha^-1 with 0.79 PO₄ equiv./t paddy. EcoX per one tone paddy and maximum environmental impacts was belonged to aquatic eutrophication (0.13 Eco-index per one tone paddy). It seems that system management including green manure, nitrogen fixing species and reduced tillage could be regarded to reduce problematic environmental impacts in rice production systems.