Rice Cultivation Methods and Their Sustainability Aspects: Organic and Conventional Rice Production in Industrialized Tropical Monsoon Asia with a Dual Cropping System

Options to tackle the sustainability challenges faced in the production of rice, including global and local environmental perspectives, need to be discussed. Here, the global warming potential, water consumption and cumulative energy demand were analyzed using a life-cycle assessment to highlight the sustainability aspects of rice production in Taiwan, where a mixed organic and conventional rice production with a dual cropping system is practiced. The results show that the conventional farming method practiced in Houbi district contributes less to global warming and annual water consumption and consumes less energy than the organic method practiced in Luoshan village on a grain weight basis. It is also more lucrative for farmers because of the higher rice yield. Considering the yield ratio based on the data from two districts, the regional characteristics are more responsible for these differences. Giving up dual cropping to avail water to other sectors by fallowing during the second cropping season is preferable from the GHG emission and productivity perspectives. However, because water shortages usually occur in the first cropping season, it is more realistic to fallow during the first cropping season when domestic and other industrial users have the higher priority. The results presented here can serve as the foundation for exploring the possibilities of options, such as new biorefinery technologies and water allocation policies, in relation to influences on GHG emissions and the national self-sufficiency of rice.