Document Type : Original Article
Authors
Seed and Plant Improvement Institute, Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran
Abstract
Introduction: Life cycle assessment (LCA) is a methodology for assessing the environmental impacts associated with a product, process or activity, by identifying, quantifying and evaluating the resources consumed, and all emissions and wastes released into the environment. This study examined the environmental impacts for Maize production under Moghan climatic conditions by using LCA methodology.Materials and methods: The analysis considered the entire system, which was required to produce one ton of maize grain. For this purpose, a functional unit was assumed based on ISO14040 methods. It included the extraction of raw materials (e. g. fossil fuels and minerals), the production and transportation of farming inputs (e. g. fertilizers) and all agricultural operations in the field (e. g. tillage and harvest). In a first step, all emissions and the consumption of resources connected to the different processes were listed in a Life Cycle Inventory (LCI) and related to a common unit, which is one ton of grain. Next a Life Cycle Impact Assessment (LCIA) was done, in which the inventory data were aggregated into indicators for environmental effects, which included climate change (global warming), acidification and eutrophication (terrestrial and aquatic ecosystems), land use, phosphate resource depletion, potassium resource depletion and water resource depletion. After normalization and weighting of the indicator values it was possible to calculate summarizing indicators for resource depletion and environmental impacts.Results and discussion: The values for climate change (global warming), acidification and eutrophication (terrestrial and aquatic ecosystems), land use, phosphate resource depletion, potassium resource depletion and water resource depletion were etismated 0.04, 0.29, 0.50, 0.11, 0.03, 2.27, 0.75, 0.03 and 0.56, respectively. So, among environmental effect categories (EcoX) the highest environmental impacts were observed in eutrophication terrestrial and acidification categories and among resource deplation categories (RDI), the depletion of fossil resources had the greatest negative environmental impact for the maize production in Moghan region.Conclusion: It seems that management systems based on low input system including organic fertilizers and minimum tillage could be regarded as alternative management strategies to reduce problematic environmental impacts.
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