Spatial transmission mechanism of the water, energy and food nexus risks for the Guangdong-Hong Kong-Macao region of China

Water, energy and food (WEF) are closely intertwined. The complex interaction can form the nexus risk due to WEF scarcity. The WEF scarcity nexus risk can cause severe economic losses to adjacent regions through regional trade chains. Investigating the spatial transmission process can help understand regional vulnerability to the WEF scarcity nexus risk. Thus, this research proposes a systematic framework of the WEF scarcity nexus risk monetization method, ecological network analysis (ENA), entropy weight model (EWM) and technique for order preference by similarity to an ideal solution (TOPSIS) to analyze the generation, evolution, transmission and evaluation of WEF scarcity nexus risk. The aims are to intuitively show the harm of WEF scarcity nexus risk through risk monetization and quantitatively analyze WEF scarcity-induced risk spatial transmission. The results indicated that the water-energy-food (W-E-F) scarcity nexus risk was a critical factor restricting regional economic development. Resource-scarce regions/sectors transferred WEF scarcity nexus risk to certain neighboring partners through network trade to ensure local demands. Especially in highly resource-dependent regions (e.g., Guangdong-Hong Kong-Macao region), Hong Kong and Macao would transfer much of the local WEF scarcity nexus risk to Guangdong province, making potential economic losses in Guangdong more significant than local losses. Instead of considering Guangdong, Hong Kong and Macao as competitors, the WEF scarcity nexus risk could be reduced if the three regions worked in a coordinated pattern. Such cooperation has implications for optimizing the industrial structure and sustainable development goals for clean water, affordable energy and food security.