Research on the Optimization of Regional Sustainable Industrial Structure Considering Water–Energy–Food–Land–Carbon Constraints

In the context of climate warming and resource shortage, balancing the relationship between economy, resources and carbon emissions has become an important challenge for sustainable development, and industrial restructuring is an effective way to effectively solve the resource shortage crisis and alleviate carbon emissions. This paper proposes a cross-regional industrial structure optimization model, which aims to maximize the economic-environmental benefits, comprehensively considers the water–energy–food–land–carbon constraints, and formulates the investment allocation scheme of the regional industrial structure. This paper takes the Chengdu metropolitan area as an actual case to verify the effectiveness of the model, and then provides a decision-making basis for the development of low-carbon economy. The results show that the corresponding industrial investment under the values of 0, 0.01, 0.05 and 0.1 increases by 14.95%, 15.30%, 18.99% and 22.14%, respectively. Therefore, with full consideration of resource utilization and environmental protection, the overall proportion of industrial investment can be further increased and the high-quality growth of the regional economy can be promoted. After optimization, the average investment in the primary industry was 266.28 × 10⁸ yuan, the investment in the secondary industry was 11,761.10 × 10⁸ yuan, and the investment in the tertiary industry was 583.93 × 10⁸ yuan. The carbon emissions of the Chengdu metropolitan area were 2112.91 × 10⁴ t, a decrease of 9.73% compared with before the optimization. Among them, the carbon emissions generated by the non-metallic mineral products industry and the chemical raw materials and chemical products manufacturing industry contribute more to the total carbon emissions of the sector. Relevant departments should promote the improvement of production processes and equipment, adopt energy-saving technologies and high-efficiency equipment, reduce energy consumption, and reduce carbon emissions. The optimization model established in this paper can make full use of existing resources and reduce the impact of economic development on the environment, which is of great significance for achieving the goal of regional "carbon neutrality" and promoting the sustainable development of regional economy.