Explaining the change of virtual groundwater transfers from China's overexploited regions through full supply chains

Abstract

Groundwater is under increasing pressure in China with unsustainable abstraction threatening eco-environment system and sustainable development. Yet it is not clear how virtual groundwater transfer through inter-provincial and international trades contributes to distant groundwater overexploitation over a period of time. This analysis traces groundwater abstraction from overexploited regions of China incorporated in the complete supply chain to final consumption, and examines drivers for dynamic changes of virtual groundwater transfers between 2007 and 2017 using the structural decomposition analysis. Groundwater use in four overexploited regions (i.e. North China Plain, Northeast China, hinterland North China and Xinjiang) were 88–91 billion m3 (about 85%–88% of national groundwater withdrawal). Inter-provincial virtual groundwater transfer presented an increasing trend with its share of total groundwater withdrawal increased from 36.4% to 45.4%, indicating an increasing reliance of regional final consumption on groundwater use beyond province boundaries. Structural decomposition analysis revealed that increasing receipt of commodities from overexploited regions was a major contributor to increasing reliance on virtual groundwater. Improved water use efficiency and consumption structure offset increasing virtual groundwater transfers from overexploited regions. The understanding gained in this study can be used by water managers and policy makers to improve the governance and management of groundwater resources.