摘要
食物生产不仅依赖水资源,同时产生大量二氧化碳排放,这种资源环境影响存在于食物系统整个产业链。为促进食物系统节水降碳,本文构建了包含5大类共23种具体食物部门的混合生命周期评价模型,对各类食物系统的完全水资源消耗和二氧化碳排放进行了核算与比较。结果表明:(1)不同食物的水资源消耗和二氧化碳排放差异明显,动物性食物的平均水资源消耗和二氧化碳排放强度分别为植物性食物的1.9~15.0倍和1.9~2.7倍;(2)食物系统直接和间接水资源消耗占比较为接近,但二氧化碳排放主要源自上游产业链的间接排放,占比高达80.9%;(3)食物系统间接水资源消耗主要来自农业部门,而间接碳排放主要来自电力生产和供应业、基础化工原料制造业、非金属矿产品行业和交通运输业;(4)从营养元素供给看,动物性食物提供蛋白质和脂肪的资源环境影响高于植物性食物,蔬菜和主食分别在提供维生素C和碳水化合物上具有最小的环境成本。基于本文结果,食物系统节水应主要提高生产环节用水效率,而降碳则主要依靠上游产业减排,特别是发电和化肥生产等行业的协同节水减碳潜力。同时,本文结果也可为未来基于环境影响制定膳食指南提供数据支撑。
Food production not only depends on water resources, but also generates a large amount of CO_(2) emission. These environmental impacts exist in the entire industrial chain of the food system. In order to save water and reduce CO_(2) emissions in the food system, this research develops a hybrid LCA model that includes 5 categories and 23 specific food sectors. Then this research accounts and compares the total water consumption and CO_(2) emissions of food systems. The results show that: (1) The water consumption and CO_(2) emissions of different foods are significantly different. The water consumption intensity of animal food is 1.9-15 times that of plant food, and the CO_(2) emission intensity is 1.9-2.7 times that of plant food. (2) The direct and indirect consumption of water is close, but the CO_(2) emissions mainly come from of indirect CO_(2) emissions from the upstream industrial chain, which accounts for 80.9%. (3) Indirect water consumption in food system mainly comes from agricultural sector, while indirect CO_(2) emissions mainly come from the power production and supply sector, basic chemical raw material manufacturing sector, non-metallic mineral products sector and transportation sector. (4) From the perspective of nutrient supply, when considering protein and fat supply, the environmental impact of animal foods is higher than that of plant foods. Vegetables and staple food have the minimum environmental cost in providing vitamin-C and carbohydrate respectively. Based on the results of this paper, water conservation in the food system should mainly rely on the improvement of water use efficiency in the direct production process, and CO_(2) reduction should focus on the upstream sectors.Especially, it should be highlighted that there embodied synergistic potential for water conversion and CO_(2) emissions reduction in the power production sector and fertilizer production sector. At the same time, the results of this paper also provide supportive data for designing a more sustainable dietary guideline
作者
刘金良
王长波
杨子彦
庞明月
王思雨
LIU Jinliang;WANG Changbo;YANG Ziyan;PANG Mingyue;WANG Siyu(Nanjing University of Aeronautics and Astronautics College of Economics and Management,Nanjing,211106,China;Key Laboratory of Three Gorges Reservoir Region’s Eco-Environment,Ministry of Education,Chongqing University,Chongqing,400045,China)
出处
《中国环境管理》
CSSCI
2022年第6期88-99,共12页
Chinese Journal of Environmental Management
基金
教育部人文社会科学基金(22YJCZH184)
江苏省高校哲学社会科学研究重大项目(2022SJZD050)
国家自然科学基金国际(地区)合作与交流项目(72161147003)。
