摘要
农业是人类活动第二大温室气体排放来源,其低碳发展对全球粮食安全具有举足轻重的作用.本文利用联合国粮食及农业组织数据库,分析了全球245个国家或地区粮食系统土地利用变化、农产品生产活动和农产品生产前后3个阶段的主要温室气体(CO_(2)、CH_(4)和N_(2)O)排放的具体活动来源、经济体来源和日常食物温室气体排放量及温室气体排放强度特征.结果表明:①1990−2020年,粮食系统温室气体(GHGs)排放量增长了13.82%,人均GHGs排放量下降了22.92%,预计2050年全球粮食系统GHGs排放量为15.39×10^(9)~17.35×10^(9)t(以CO_(2)计).②粮食系统三部分活动−土地利用变化、农产品生产活动和农产品生产前后的GHGs排放量占比分别为45.82%、19.51%和34.67%,农产品生产前后阶段是30年间GHGs排放量增长的主要动力,其GHGs排放量翻倍,原因是粮食系统运输和消费过程中损失和浪费现象比较严重.③粮食系统中CO_(2)、CH_(4)和N_(2)O分别占全球GHGs的15.29%、10.43%和4.45%,其最大来源分别是森林净转换、肠道发酵以及留在牧场上的粪便.森林净转换排放的CO_(2)占粮食系统CO_(2)来源的37.03%,肠道发酵排放的CH_(4)占粮食系统CH_(4)来源的52.52%,留在牧场上的粪便排放的N_(2)O占粮食系统N_(2)O来源的33.35%.④粮食系统GHGs排放量前10位国家的排放总量超过全球245个国家或地区粮食系统GHGs排放量的1/2.⑤牛肉、大米和生牛乳是日常食物中GHGs排放量较大的3种食物,占整个粮食系统GHGs排放量的25.70%;反刍动物肉类的GHGs排放强度是其他食物的几十甚至上百倍.通过粮食系统GHGs来源特征的研究,提出以下几点建议:①提升农产品生产前后阶段管理水平,特别是改善粮食运输、加工环节管理,加强节约粮食宣传教育和废物管理水平,提倡垃圾分类,发展生物质能利用技术;②优化农业生产模式,控制畜牧业规模,增加种植业强度的同时,增强抑制反刍动物、水稻的CH_(4)排放和提高氮肥利用等技术的研发,减少化肥、农药和饲料的使用,通过有机农业、旋耕、轮作等方式,减少GHGs的排放;③推广低碳生活方式,多食用本地生产的食品、除大米外的谷物,少食用反刍动物肉类,以GHGs排放强度较低的鸡肉和猪肉为主要蛋白质补充源.要从技术研发、农业生产模式、农业生产效率、能源结构、废弃物管理和日常生活方式等方面全方位地降“碳”.
Agriculture is the second largest contributor to greenhouse gas(GHGs)emissions caused by human activities.Its low-carbon development plays a crucial role in ensuring global food security.This article using the data from the United Nations Food and Agriculture Organization to analyze the specific sources,economic aspects,and daily food-related greenhouse gas emissions and greenhouse gas intensity characteristics of major greenhouse gases(CO_(2),CH_(4)and N_(2)O)in the global food system.The results show that:(1)From 1990 to 2020,GHGs emissions from the food system increased by 13.82%,while per capita GHGs emissions decreased by 22.92%.It is estimated that the global food system GHGs emissions will be 15.39×10^(9)-17.35×10^(9)t CO_(2)eq in 2050.(2)Production before and after the food system is the primary driver for increased GHGs emissions.During the 30 years,the GHGs emissions from this part doubled,mainly due to the loss and waste during the transportation and consumption process in the food system.(3)CO_(2),CH_(4)and N_(2)O in the food system account for 15.29%,10.43%and 4.45%of global GHGs,respectively.The largest sources are forest net conversion,intestinal fermentation,and feces left in the pasture.The CO_(2)emissions from forest conversion account for 37.03%of the CO_(2)emissions from the food system,the CH_(4)emissions from intestinal fermentation account for 52.52%of the CH_(4)emissions from the food system,and the N_(2)O emissions from manure left on pasture account for 33.35%of the N_(2)O emissions from the food system.(4)The total greenhouse gas emissions from the top 10 countries in the food system exceed half of the global greenhouse gas emissions.(5)Beef,rice,and raw milk are three types of foods with significant greenhouse gas emissions among daily foods,accounting for 25.70%of the GHGs in the entire food system.The greenhouse gas intensity of meat from ruminant animals is tens or even hundreds of times that of other foods.Finally,the article proposes the following main recommendations:(1)Improve the management level in the pre-and post-production stages,especially improve grain transportation and processing management,strengthen the promotion of grain conservation and waste management,promote garbage classification,and develop biomass energy utilization technology.(2)Optimize agricultural production methods,control the scale of animal husbandry,increase planting intensity,enhance research and development of technologies to inhibit CH_(4)emissions from ruminants and rice,improve nitrogen fertilizer utilization,reduce the use of chemical fertilizers,pesticides,and feed,and reduce greenhouse gas emissions through organic agriculture,rotary tillage,and crop rotation.(3)Promote a low-carbon lifestyle,eat more locally produced food and grains other than rice,eat less meat from ruminant animals,and use chicken and pork with lower greenhouse gas intensity as the main sources of protein supplements.Carbon emission reduction should be comprehensive from the perspectives of technology research and development,agricultural production methos,agricultural production efficiency,energy structure,waste management,and daily lifestyle.This research provides valuable insights for ensuring global food security under the‘low-carbon’agricultural model.
作者
汤宏波
吕新华
李富山
赵素婷
TANG Hongbo;LÜXinhua;LI Fushan;ZHAO Suting(Hubei Key Laboratory of Big Data in Science and Technology,Wuhan Documentation and Information Center,Chinese Academy of Sciences,Wuhan 430079,China)
出处
《环境科学研究》
CAS
CSCD
北大核心
2023年第11期2031-2039,共9页
Research of Environmental Sciences
基金
中国科学院战略研究与决策支持系统建设专项课题(No.GHJ-ZLZX-2023-06)
中国科学院国际合作局出国专题研究项目阶段性成果(科际批字0034号)。
作者简介
汤宏波(1980-),男,贵州锦屏人,副研究员,硕士,主要从事绿色发展、碳排放研究,tanghb@mail.whlib.ac.cn.
