关键词: 碳限额与交易机制, 供应链竞争, 碳排放, 决策结构

Abstract: With the increasing severity of environmental problems， China has proposed to achieve carbon peak by 2030 and carbon neutrality by 2060, for which it has formulated a carbon cap-and-trade mechanism and officially launched the construction of a unified national carbon trading market in 2021. In this context, the control of carbon emissions by firms has been normalized, and exploring the impact of carbon cap-and-trade mechanism on supply chain competition decision-making is a realistic problem faced by firms nowadays. Therefore, based on the cap-and-trade mechanism, this paper considers the important factor of inter-chain competition in supply chains, and explores the optimal decision-making, structural choices, and policy design of supply chains to reduce emissions. This paper focuses on the decision-making problem of inter-chain competition in low-carbon supply chains under the carbon cap-and-trade mechanism. First, we construct a low-carbon chain-to-chain competition model. Under the cap-and-trade mechanism and the existence of supply chain competition, two low-carbon supply chains produce and sell heterogeneous and substitutable products, and compete in the same market, with each supply chain consisting of a manufacturer and a retailer. Vertically, the manufacturer is the dominant player in the Stackelberg game; horizontally, there is a Cournot game between the supply chains based on the supplied quantity. Under centralized decision making, each manufacturer and its retailer make joint decisions to maximize supply chain profit. Under decentralized decision-making, each manufacturer and its retailer make decisions independently, each considering its own profit maximization. The two decision-making structures of the supply chain are modeled and solved. We compare the advantages and disadvantages of the different decision-making approaches and the impact of inter-chain competition on the decision-making and profitability of the supply chain and its members. At the same time, theoretical and numerical analyses are carried out on the findings of the study, so as to understand more intuitively the changes of supply chain members’ decision-making and profits under inter-chain competition, and to further explore the choice of decision-making structures in the supply chain. Through the above research, the following conclusions are mainly drawn: First, the profits of supply chain and its members are negatively correlated with the intensity of competition. When the competition intensity is low, centralized decision-making is the dominant decision structure to achieve supply chain profit improvement, but when the competition is too intense, centralized decision-making can not improve the supply chain profit, and at this time, decentralized decision-making is the dominant decision structure. Second, the government’s increase in carbon quotas will improve the profits of each party and the supply chain, but it cannot influence the production and emission reduction decisions of the firms. Third, there can be a moderate carbon price in the carbon trading market, and a carbon price that is too high or too low will not be able to incentivize firms to minimize the carbon emissions of their products.

Key words: carbon cap and trade mechanism, supply chain competition, carbon emission, decision-making structure