制造业出口贸易隐含碳排放的计量与驱动机制研究——碳关税视角下的广东省证据

Measurement and Driving Mechanism of Embodied Carbon Emissions in Manufacturing Exports—Evidence from Guangdong Province in the Context of Carbon Tariffs

摘要: 欧盟碳边境调节机制自2026年起正式征收，出口导向型制造业省份面临的碳成本约束日益显性化。本文以广东省为例，利用2010~2023年26个制造业细分行业的面板数据，采用经进口中间品修正的单区域投入产出模型测算出口隐含碳排放，并以单位产出隐含碳(碳强度)为被解释变量，运用聚类稳健最小二乘、组内去均值、HAC稳健估计、一阶差分与两步系统广义矩估计五种方法识别其驱动机制。结果表明：全省出口隐含碳排放呈先降、后升、再趋稳的轨迹；外商直接投资对行业碳强度具有稳健的减排效应，支持“污染光环”假说，但该效应在2018年后趋于不显著；约54%的行业存在较强的碳锁定。情景模拟显示，在60美元/吨的基准税率下，全省出口隐含碳关税成本约为577.3亿元，相当于2023年规上工业利润的5.46%；按碳强度排序，黑色金属冶炼、建材、造纸与石油加工业受冲击最为敏感，而按利润侵蚀口径，纺织业承压最重。稳健性检验与敏感性分析表明，核心结论稳健。据此提出分梯队、分行业的低碳转型政策建议。

Abstract: The EU Carbon Border Adjustment Mechanism (CBAM) has officially entered into force for tariff collection as of 2026, rendering the carbon cost constraints confronting export-oriented manufacturing provinces increasingly tangible. Taking Guangdong Province as the research context, this paper employs panel data covering 26 disaggregated manufacturing sub-sectors over the period 2010~2023. A single-region input-output model adjusted for imported intermediate inputs is adopted to quantify the embodied carbon emissions in exports. Using embodied carbon per unit of output (i.e., carbon intensity) as the dependent variable, this study identifies its underlying driving mechanisms through five econometric specifications: cluster-robust ordinary least squares, within-group mean detrending, HAC robust estimation, first-differenced regression, and the two-step system generalized method of moments. The empirical results indicate that the trajectory of Guangdong’s total export embodied carbon emissions follows a three-phase pattern: an initial decline, a subsequent rise, and a final trend toward stabilization. Foreign direct investment exerts a robust emission-reduction effect on sectoral carbon intensity, which validates the “Pollution Halo Hypothesis”, whereas this mitigating effect becomes statistically insignificant after 2018. Approximately 54% of the sampled industries exhibit strong carbon lock-in effects. Scenario simulation reveals that under the benchmark carbon tariff rate of 60 USD per ton, the total CBAM-related cost for Guangdong’s export sector amounts to roughly 57.73 billion RMB, equivalent to 5.46% of the province’s industrial profits of enterprises above designated size in 2023. When ranked by carbon intensity, ferrous metal smelting, building materials, papermaking, and petroleum processing are the most vulnerable sectors to CBAM shocks, while the textile industry faces the severest pressure in terms of profit erosion. A battery of robustness checks and sensitivity analyses confirms the reliability of the core findings. This paper concludes with tiered, sector-specific policy recommendations to facilitate targeted low-carbon transition.