Abstract: Global warming has become an important obstacle to the sustainable development of the earth. The reduction of total and unit carbon emissions has become the core of national emission reduction mechanism design.Base on this, the carbon trading supply chain is composed of government, enterprises and consumers, in which consumers buy products based on their own low carbon preference, the government makes the quota and carbon guidance price based on the optimal principle of industrial social welfare, and enterprises are engaged in the production and sales under the constraints of emission reduction mechanisms. Through the establishment of a hybrid game model, the impact of the carbon emission reduction mechanismwas compares and analyzes, which considers the dual heterogeneity. The results show that the new emission reduction mechanism can better mobilize the participation enthusiasm of consumers and enterprises in the optimization of industrial social welfare, and achieve the two-way incentives of heterogeneous enterprises to reduce emissions. The key factors are the consumer low carbon preference and the unit carbon emission difference, which affect the scheme of implementation of the mechanism and the emission reduction performance. Consumers' low carbon preferences determine the industry's optimal carbon price and quota allocation rules, and affects corporate decision-making and product prices at both active and passive levels. The unit carbon emissions difference is an important factor affecting the direction of industry's emission reduction, enterprise profit and consumer's active payment. Strict division of unit carbon emissions is conducive to the improvement of emission reduction. The quota rate is an important factor in achieving emission reduction incentives, and the difference between the quota rate and the independent quota rate is one of the causes of fluctuations in carbon price. The research also shows that too low unit carbon emission difference is not suitable forthe division of enterprise heterogeneity, and the "carbon benefit incentive" should be weakened.

Key words: carbon trading, emission reduction preference, low carbon preference, unit carbon emissions, heterogeneity