【摘要】 关税战直接影响农产品进口，本文聚焦植物油料进口，以2018年中美贸易摩擦为政策时间节点，利用2015-2024年联合国商品贸易数据，采用社会网络分析（SNA）与双重差分法（DID）相结合的方法，对美实施的关税反制政策实际效果展开评估，重点分析该政策在植物油料进口抑制、贸易转移与进口来源结构重构等方面的作用，通过构建进口贸易网络、识别政策净效应等角度，对政策作用进行系统解析。结果显示：政策实施后，中国对美植物油料进口依赖度显著下降13.7个百分点，美国市场份额由26%降至10%，表现出强烈的贸易抑制效应；植物油料进口结构发生明显贸易转移，巴西成为最大受益国，中国对其进口依赖度上升14.2个百分点，进口网络由“双核心依赖”结构转向以巴西为核心、多国协同的“紧凑高效”模式，系统提升进口供应网络韧性。基于上述结果，本研究从持续优化进口来源布局、加强国内油料产业支持和深化与重点国家合作三方面提出建议，为中国在复杂国际贸易环境中制定农业贸易政策提供实证依据。更多还原

【Abstract】 The tariff war directly affects import of agricultural products. This paper focuses on the import of vegetable oilseeds. Taking the Sino-US trade friction in 2018 as the policy time node, it uses the UN Comtrade Data from 2015 to 2024 and combines Social Network Analysis(SNA) with the Difference-in-Differences(DID) method to evaluate actual effect of the US tariff countermeasures policy. It mainly analyzes the role of this policy in suppressing import of vegetable oilseeds, trade diversion and reconstruction of import source structure. Through the construction of import trade network and the identification of net policy effect, the policy effect is systematically analyzed. Results show that after the policy implementation, China′s dependence on US import of vegetable oilseeds has significantly decreased by 13.7%. The US market share has dropped from 26% to 10%, demonstrating a strong trade suppression effect. There has been a significant trade diversion in the import structure of vegetable oilseeds, with Brazil becoming the biggest beneficiary. China′s dependence on its imports has increased by 14.2%, and the import network has shifted from a "dual-core" structure to a "compact and efficient" model centered on Brazil, systematically enhancing the resilience of the import supply network. Based on the above, this study proposes suggestions from 3 aspects: continuously optimizing the layout of import sources, strengthening domestic oilseed industry support, and deepening cooperation with key countries, providing important empirical evidence for China to formulate agricultural trade policies in a complex international trade environment.更多还原