Ecological relationships of global construction industries in sustainable economic and energy development

Value-added trade has increased rapidly in recent decades in the context of globalisation. This paper aims to measure the energy embodied in the value-added trade and the ecological relationships in the networks of the international construction industries. A hybrid method which combines ecological network analysis and the input–output method has been adopted. The direct energy intensities in most countries ranged from 0 to 3.0 trillion joules per million US$ and the dominant relationships were control and exploitation in the selected 15 years. For the construction sector, the negative relationships were dominant at 63.9% in Australia and 79.19% in China. The ratio of positive relationships increased from 24.3% to 31.5%, while the ratio of negative relationships declined from 75.7% to 68.5% over the 15 years. The mutualism index ranged from 0.72 to 0.98 over the 15 years, maintaining a value less than 1. In contrast, the synergism index had an increase of 12.2 over the 15 years. The results indicate that both direct energy intensity and the value-added ratio are important factors in relation to the energy embodied in value-added trade. Sectoral influence on the national industrial system has been interpreted in this paper to stimulate further research.