Dynamic potassium flows analysis in China for 2010–2019

Abstract

China is the largest potassic fertilizer user, but with very limited potassium reserve. This study aims to present an accurate and dynamic potassium inventory from a life cycle perspective. The spatiotemporal features of the main anthropogenic potassium flows and stocks are uncovered by applying substance flow analysis (SFA). Results show that China's potassium demand had doubled and domestic extraction of potassium resources had increased by 44%, from 2.89 Mt in 2010 to 4.15 Mt in 2019, due to the increasing population and rapid agricultural development. In terms of potassium usage, regional disparity existed and the overall usage efficiency was low. A total of 63.18 megatons (Mt) potassium was discharged into local environment as wastes, and a surplus of 24.89 Mt potassium was kept in soil as stock during the study period. Scenarios analysis results show that the total potassium demand will reach 9.56 Mt, 10.34 Mt, 11.32 Mt, 9.09 Mt, and 9.80 Mt under SSP1, SSP2, SSP3, SSP4 and SSP5 scenarios, respectively. Such findings indicate that China's potassium reserve will be quickly depleted. Based upon these findings, several policy recommendations are raised, including sustainable potassium resource supply, the recycling of potassium resources, and advanced technologies to further improve potassium resource efficiency.