Spatial and temporal disparity of the in-use steel stock for China

The in-use steel stock is an important indicator of urban metabolism. However, there is a big gap in the in-use steel stock level among different regions because of diverse driving factors and the mechanism of how the factors act on the in-use steel stock. This strongly aggravated the difficulty of accounting in-use steel stock. To identify the comprehensive disparity, this paper took China's provinces as the empirical context and established a hybrid accounting model framework by considering the unique characteristics for the downstream steel-using sectors. The results show that China's per capita in-use steel stock have increased by 1.96 times from 2002–2016, reaching 3.65 ton/cap in 2016. Therein, the building sector always contributes more than 50 % of the increase. Based on the change of per capita in-use steel stock and socio-economic factors, Chinese provinces can be divided into three clusters. The driving factors have different effects on the per capita in-use steel stock in three types of provinces. For example, an increase of 1 % in the urbanization rate would increase the per capita in-use steel stock for the infrastructure sector by 0.55%ö2.69% in these three types of provinces. In addition, foreign direct investment, the aging population and per capita income are the main factors affecting the in-use steel stock. From 2021–2035, it would be the peak period of scrap production in the building sector. The government is suggested to implement fiscal preferential policies to achieve effective recycling of scrap.