水产品贸易对土地利用、碳排放和生物多样性的影响

Impact of aquatic product trade on land use, carbon emissions and biodiversity

  • 摘要: 目前全球约37%的水产品进入国际贸易而非本地消费, 因此水产品贸易与全球资源和环境可持续性的联系日益密切。然而, 现有研究多集中于分析水产品替代畜禽产品导致的资源环境代价变化, 而针对水产品贸易与“资源-环境-生物多样性”影响的研究还较缺乏。本文利用环境足迹和全生命周期相结合的方法, 综述了水产品的贸易量、贸易品种与贸易国家的变化规律, 并依据贸易与资源及环境的关系, 分析了水产品贸易对土地利用、碳排放和生物多样性的影响。结果发现, 2020年水产品出口量较1976年增长了5倍, 且贸易增速呈现出“先快后稳”的趋势。水产品贸易国由欧洲南部扩大至全球范围。捕捞水产品, 如沙丁鱼、鳕鱼和金枪鱼是主要的贸易品种; 养殖水产品在总水产贸易产品中的比重快速增加, 由1976年的5%增加至2020年的25%。水产品贸易中养殖产品的增加影响全球土地利用变化、虚拟温室气体排放, 以及水生和陆地生态系统生物多样性。因此, 未来若要实现全球水产品可持续生产和消费, 需发达国家和发展中国家间共享水产品先进生产技术、优化贸易结构、调整贸易品种。例如, 在生产端优化养殖结构、技术和产业链, 在需求端减少对高资源环境代价品种的消费, 在贸易端限制高资源环境代价品种的交易。

     

    Abstract: Currently, the aquatic product trade plays an increasingly important role in global resources and the environment because 37% of global aquatic products are traded rather than consumed locally. Previous studies have mainly analyzed the resource and environmental costs caused by the substitution of aquatic products for livestock products. However, little is known about the impacts of aquatic product trade on the ‘resource-environment-biodiversity’ system. Here, a review was conducted using a combined method of environmental footprint and life-cycle assessment. This review focuses on (1) the changes in trade volume, trade species, and trade countries, and (2) the impact of the aquatic product trade on land use, greenhouse gas emissions (GHG), and biodiversity. The results showed that the export volume of aquatic products in 2020 increased five-fold compared with that in 1976, and the growth rate of trade followed a profile termed ‘fast and then stable’. The aquatic product trade has expanded from southern Europe to the rest of the world. The major trade species are capture products (including sardines, cod, and tuna). However, the share of aquaculture products in total aquatic trade products has increased linearly since 1976: from 5% in 1976 to 25% in 2020. The increase in the aquaculture product trade affects global land-use change, virtual GHG emissions, and biodiversity in aquatic and terrestrial systems. Therefore, to achieve the sustainability of global aquatic products in the future, it is necessary to share advanced production technologies, optimize trade structures, and adjust trade species globally. More specifically, producers should optimize aquaculture structure, technology, and the industrial chain, and consumers should reduce the consumption and trade of aquatic products with high resource and environmental costs.