Eco-efficiency assessment of material use: The case of phosphorus fertilizer usage in Japan's rice sector

Abstract

To raise the eco-efficiency of the economy, it is important to not only investigate the eco-efficiency of specific products but also to ascertain whether the resources are used effectively throughout the life cycle. In this paper, we address eco-efficiency of agricultural use of phosphorus in Japan in the years 2005, 2010, and 2011. The increase in revenue from crops due to the use of phosphorus-based fertilizer is considered. The method used allows us to isolate the impact of a single nutrient and to convert this to a monetary value. For impact assessment of P resource use, we combine life-cycle inventory (LCI) data with LIME 2 (Life-cycle Impact Assessment Method based on Endpoint modeling) method. The most significant environment impact of the phosphorus chemical fertilizer life cycle is found to be on climate change by high chemical fertilizer. In 2005, provided service of phosphorus resource use was estimated as the highest while value added service of phosphorus increased, resulting in an uptick in eco-efficiency. During the study period, the lowest eco-efficiency of P resource use resulted in 2011. The results from this study, and the methods used, should be of great interest to industry, the research community, and policy makers concerned with resource efficiency.