Research on the Sustainable Development of Natural-Social-Economic Systems Based on the Emergy Accounting Method-A Case Study of Liyang in China

Coordinating the relationship between resources, environmental protection, and economic development is essential for regional sustainable development. Various frameworks and models for quantifying the sustainable development of regional natural-social-economic systems have been produced. This paper focused on measuring regional sustainable development from the perspective of sustainable consumption and production. The study improved the emergy sustainable indices and the evaluation system commonly used in the method of emergy accounting by introducing input and output emergy into the emergy flows. Then, we proposed new subsystem sustainable indexes for evaluating and analyzing the sustainable development trend of the complex natural-social-economic system in Liyang from 2005 to 2020 by adopting the entropy weight method. The results showed that Liyang was generally in a state of sustainable development, with good social sustainability. The economic and natural sustainability indexes were low, which might cause unsustainable risks in the future. From the input structure and production efficiency perspective, the secondary industry with the highest emergy output has a meager net output rate. In contrast, the tertiary industry has a higher net output rate (NOR) and better output efficiency, which should be the core industry in the region's future development. From the perspective of environmental impact and resource and environmental carrying capacity, the natural contribution rate and environmental carrying rate should be improved and the waste emergy rate necessary to be reduced. This study hopes to provide implications for formulating regional land use, industrial planning, and sustainable development policies.