Food-energy-emission nexus of rice production in China

As the world's largest rice-producing country, China's energy and environmental performance related to rice production have attracted widespread attention. To achieve a sustainable rice production with low energy expenditure and environmental impacts, systematic assessments are required to examine the life cycle food-energy-emission nexus of rice production system on a national scale. This study employed energy analysis and systematic indicators to explore the interplay among productivity, energy inputs, and greenhouse gas emissions in China's rice production from 1998 to 2018. We found that energy inputs decreased by 11% during the study period, mainly due to the reduction of energy inputs from fertilizer, labor, and animal power. However, energy structure has become increasingly dependent on nonrenewable energy. Generally, net energy and energy use efficiency increased during the period from 1998 to 2013, implying a substantial increase in production efficiency from energy input. Meanwhile, global warming potential from rice production increased by 20% from 1998 to 2018, primarily due to increased methane emissions. Nevertheless, environmental loading intensity including yield- and net energy-scaled global warming potential of rice production showed a decreasing trend, accompanied by dramatic improvements in food production and energy efficiency, especially since 2013. Strategies for achieving energy-efficient and eco-friendly agriculture for China and other countries around the world with similar bio-physical background are discussed.