A trade policy could generate both economic and environmental impacts. This work is focused on the impacts of a bilateral trade policy on ballast water-mediated nonindigenous species (NIS) spread risk. Taking the hypothetical Sino-US trade restriction as an example, we integrate a computable general equilibrium model and a higher-order NIS spread risk assessment model to examine the impacts of bilateral trade policy on both the economy and NIS spread risks. We have two important findings. First, the Sino-US trade restriction would cause decreases in NIS spread risks to China and the US, as well as to three quarters of worldwide countries/regions. However, the rest one fourth would experience increased NIS spread risks. Second, the relationship between changes in exports and changes in NIS spread risks might not be directly proportional. This is observed with 46% of countries and regions that would see their exports increase but their NIS spread risks drop, with positive impacts on both their economies and environment under the Sino-US trade restriction. These results reveal both broader global impacts as well as the decoupled economic and ecological impacts of a bilateral trade policy. These broader impacts demonstrate the necessity for national governments, which are parties to bilateral agreements to give due consideration to the economic and environmental impacts on countries and regions outside of the agreement.

中文翻译：

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双边贸易政策对压载水介导的物种传播风险的全球影响：以中美贸易为例

贸易政策可以产生经济和环境影响。这项工作的重点是双边贸易政策对压载水介导的非本土物种 (NIS) 传播风险的影响。以假设的中美贸易限制为例，我们整合了一个可计算的一般均衡模型和一个高阶 NIS 利差风险评估模型来检验双边贸易政策对经济和 NIS 利差风险的影响。我们有两个重要发现。首先，中美贸易限制将导致中美两国以及全球四分之三国家/地区的 NIS 利差风险降低。但是，其余四分之一的 NIS 传播风险会增加。其次，出口变化与 NIS 利差风险变化之间的关系可能不成正比。46% 的国家和地区出口增加，但 NIS 利差风险下降，在中美贸易限制下对其经济和环境产生积极影响。这些结果揭示了双边贸易政策更广泛的全球影响以及脱钩的经济和生态影响。这些更广泛的影响表明，作为双边协议缔约方的国家政府有必要适当考虑对协议之外的国家和地区的经济和环境影响。这些结果揭示了双边贸易政策更广泛的全球影响以及脱钩的经济和生态影响。这些更广泛的影响表明，作为双边协议缔约方的国家政府有必要适当考虑对协议之外的国家和地区的经济和环境影响。这些结果揭示了双边贸易政策更广泛的全球影响以及脱钩的经济和生态影响。这些更广泛的影响表明，作为双边协议缔约方的国家政府有必要适当考虑对协议之外的国家和地区的经济和环境影响。