Eco-Efficiency Assessment of Intensive Rice Production in Japan: Joint Application of Life Cycle Assessment and Data Envelopment Analysis

Kiyotaka Masuda

doi:10.3390/su11195368

Abstract

To promote sustainable agriculture worldwide, it is important to understand what constitutes eco-efficiency for rice, a staple food in many countries. This study examined whether expanding the scale of rice farming contributed to the improved eco-efficiency of intensive rice production in Japan. Both life cycle assessment (LCA) and data envelopment analysis (DEA) were used to measure comprehensively the eco-efficiency of rice production. A DEA window analysis technique with two DEA inputs (global warming and eutrophication from the LCA results) and one DEA output (weight-based rice yield) was applied to the statistical data for 2005–2011 categorized by the size of rice farms. The results indicate that expanding the size of rice farms is an effective way of improving the eco-efficiency of intensive rice production in Japan. The important factors for improving eco-efficiency are the implementation of economies of scale, reduced outsourcing of farm work, and savings in chemical fertilizers and pesticides. Expansion of the size of rice farms through the recent abolition of the rice production adjustment program will also contribute to improving the eco-efficiency of Japanese rice production.

Highlights

In recent decades, intensification of agriculture by various means including irrigation, fertilizers, pesticides, and mechanization has contributed to an increase in crop production but has caused harmful impacts such as global warming and eutrophication of terrestrial and aquatic environments [1,2].Sustainable intensification that can maintain high crop yields under acceptable environmental impacts is required to meet the growing demand for food [3]
Soil conditions and water regimes that are site-specific are not directly affected by an increase in the size of rice farms. Even with these limitations, the results of this analysis demonstrate that expansion of the size of rice farms is an effective way to improve the eco-efficiency of Japanese rice production
Life cycle assessment (LCA) and data envelopment analysis (DEA) methods were jointly applied to examine whether expansion of the size of rice farms contributed to improvement of the eco-efficiency of intensive rice production in Japan

Summary

Introduction

Sustainable intensification that can maintain high crop yields under acceptable environmental impacts is required to meet the growing demand for food [3]. Efficient nutrient and water use, good soil fertility management, improved disease and pest control, and environmentally friendly farming practices are effective ways to achieve sustainable intensification of crop production [3]. Because eco-efficiency can integrate both economic and environmental aspects of production [4], it is a useful index to evaluate sustainable intensification of crop production. Eco-efficiency is defined as a product or service value per unit of environmental impact such as energy consumption, materials consumption, and greenhouse gas emissions [4]. Life cycle assessment (LCA), which is a tool for analyzing the environmental impact of products at all stages in their life cycle (from the cradle to the grave) [5], is used to calculate the values assigned to the denominator of the eco-efficiency equation, represented as Product or service value Environmental impact [4]

Methods

Results

Discussion

Conclusion