Combined Application of a Multi-Objective Genetic Algorithm and Life Cycle Assessment for Evaluating Environmentally Friendly Farming Practices in Japanese Rice Farms

Abstract

When organic practices may have negative environmental effects, understanding the trade-offs between the economic and environmental outcomes of organic agriculture is essential in its promotion. This paper examines whether organic rice was planted in Japanese rice farms using the combined application of a multi-objective genetic algorithm and life cycle assessment. A modeled farm with 30 hectares (ha) of paddy fields is constructed using information from an agricultural management handbook. The planted crops considered are environmentally friendly rice with reduced use of chemical fertilizers and synthetic pesticides, organic rice, conventional wheat, and conventional soybeans. A bio-economic farm model with both economic and environmental objectives is created. The Pareto-optimal solutions indicate that the planted area of organic rice is 2.3 ha, at best, in the modeled farm. The cultivation of organic rice is likely to be constrained compared with that of environmentally friendly rice, and even though it produces an increase in income, it does not necessarily exert positive effects on the environment. The findings suggest that when organic farming has negative impacts, countermeasures against problems that emerge through its practice should be included in the essential requirements for subsidization.