Institute of Geographic Sciences and Natural Resources Research , Chinese Academy of Sciences , 100101 Beijing , P. R. China.
SDU Life Cycle Engineering, Department of Chemical Engineering, Biotechnology, and Environmental Technology , University of Southern Denmark , 5230 Odense , Denmark.
Environ Sci Technol. 2019 May 7;53(9):5133-5142. doi: 10.1021/acs.est.8b06079. Epub 2019 Apr 10.
Meat production and consumption contribute significantly to environmental impacts such as greenhouse gas (GHG) emissions. These emissions can be reduced via various strategies ranging from production efficiency improvement to process optimization, food waste reduction, trade pattern change, and diet structure change. On the basis of a material flow analysis approach, we mapped the dry matter mass and energy balance of the meat (including beef, pork, and poultry) supply chain in Germany and discussed the emission reduction potential of different mitigation strategies in an integrated and mass-balance consistent framework. Our results reaffirmed the low energy conversion efficiency of the meat supply chain (among which beef was the least efficient) and the high GHG emissions at the meat production stage. While diet structure change (either reducing the meat consumption or substituting meat by edible offal) showed the highest emissions reduction potential, eliminating meat waste in retailing and consumption and byproducts generation in slaughtering and processing were found to have profound effect on emissions reduction as well. The rendering of meat byproducts and waste treatment were modeled in detail, adding up to a net environmental benefit of about 5% of the entire supply chain GHG emissions. The combined effects based on assumed high levels of changes of important mitigation strategies, in a rank order considering the level of difficulty of implementation, showed that the total emission could be reduced by 43% comparing to the current level, implying a tremendous opportunity for sustainably feeding the planet by 2050.
肉类生产和消费对环境影响（如温室气体排放）有重大贡献。可以通过各种策略来减少这些排放，包括提高生产效率、优化流程、减少食物浪费、改变贸易模式和调整饮食结构。本文采用物质流分析方法，描绘了德国肉类（包括牛肉、猪肉和家禽）供应链的干物质质量和能量平衡，并在综合和质量平衡一致的框架内讨论了不同缓解策略的减排潜力。研究结果证实了肉类供应链的能量转换效率低（其中牛肉的效率最低），且在肉类生产阶段温室气体排放高。饮食结构变化（减少肉类消费或用可食用的动物内脏代替肉类）显示出最大的减排潜力，而减少零售和消费中的肉类浪费以及屠宰和加工过程中的副产物生成也对减排有深远影响。本文详细模拟了肉类副产物的加工和废物处理，对整个供应链温室气体排放的净环境效益约为 5%。基于假设的重要缓解策略的高水平变化的综合影响，按照实施难度的级别进行排序，结果表明，与当前水平相比，总排放量可减少 43%，这意味着到 2050 年为养活地球提供可持续的机会巨大。
