Reveal the inequality hidden in industry land use by integrating domestic trade and the industry efficiency.

Although industrial land accounts for a low percentage of the land surface, it can significantly affect the development of the economy and the environment. Unbalanced development makes industry efficiency differ vastly across China. Industry products embodied in domestic trade link the indirect use of industry inputs and outputs. Regional inequality needs to be more scientifically checked by comprehensively considering both trade and the efficiency, which may be determined by diverse indices. Accordingly, this study examined industrial land use among provinces and the efficiency, identified the embodied land, developed approaches to ascertain how industrial land use would change without domestic trade, and revealed the inequalities in industrial land by considering the trade. Results found that provinces along Chinas coastline usually have a highly industrialised area, and the developed regions usually have high efficiency. Guangdong, Henan, Jiangsu, Shanghai, Shandong, Liaoning, Anhui, Hebei, and Heilongjiang have high values in both industrial land serving external provinces and the reverse use in external provinces. Through domestic trade, China saved a total of 462 km of land to be converted into industrial land, which is mainly due to developed regions providing industrial land use to undeveloped regions with low efficiency. The inequality analysis shows that most provinces were in a moderate state. Heilongjiang, Gansu, and Guangxi have obvious disadvantages. Some suggestions have been made for harmonious industry development and enhanced efficiency, such as the implementation of efficiency and price-based land use policies, industry and energy structure optimisation, technological improvement, and appropriate compensation.