北京市农田生态系统碳足迹及碳生态效率的年际变化研究  

Interannual Variations of the Carbon Footprint and Carbon Eco-efficiency in Agro-ecosystem of Beijing,China

作　　者：田志会[1,2,3] 马晓燕[1,2,3] 刘瑞涵[4] 

机构地区：[1]北京农学院园林学院,北京102206 [2]北京乡村景观规划设计工程技术研究中心,北京102206 [3]城乡生态环境北京实验室,北京102206 [4]北京农学院经管学院,北京102206

出　　处：《农业资源与环境学报》2015年第6期603-612,共10页Journal of Agricultural Resources and Environment

基　　金："粮经作物产业技术体系北京市创新团队"建设专项(BFCIC-13);北京市属高等学校创新团队建设与教师职业发展计划项目(IDHT20150503);科研基地建设科技创新平台项目(PXM2015_014207_000010);城乡生态环境北京实验室建设项目(PXM2015_014207_000014)

摘　　要：近年来,由于北京城市功能的疏解以及郊区城市化进程的加快,使北京市农田生态系统受到了较大的冲击。本文以北京农田生态系统作为研究对象,对2004—2012年农田生态系统的碳汇、碳源、碳足迹以及碳生态效率的年际变化进行了研究,以明确其在北京城市发展中的功能与地位,为北京市健康持续发展及产业布局提供理论依据。结果表明:北京农田生态系统碳汇总体呈增加趋势,年递增幅度为2.8%,年平均碳蓄积量为105.82万t,决定其碳汇功能的主要因素是粮食作物中玉米与小麦的经济产量及种植面积。北京农田生态系统的年均碳排放量为27.6万t,基本呈现逐年降低的趋势,年均递减1.3%,决定碳排放量的主要因素为农业化学品中氮素化肥的施用量。北京市农田生态系统年均碳足迹为5.71 hm2,呈逐年降低的趋势,年递减率为5.5%,处于碳生态盈余状态,但是由于近年北京市耕地面积的减少,碳生态盈余量呈下降趋势;北京农田生态系统的碳生态效率较高,年均为3.854 kg C·kg^(-1)CE,农业生产处于较高的持续状态。Suburban farmland ecosystems are known to be affected by intensive land use/cover change （LUCC） during the process of urbanization in Beijing. We investigated inter-annual changes in carbon sequestration, source, footprint, and eco-efficiency from 2004 to 2012 in the agro-ecosystem of suburban Beijing. Our findings indicated that： （ 1 ） Carbon sink increased 2.8 percent annually and the average annual carbon storage amount was 1 058 200 t, with food crops constituting the highest proportion at 80.4% of carbon storage in farmland ecosys- tems, of which maize contributed 68.5% as the largest constituent; （2） Carbon emission in the system showed a gradually decreasing trend, with agricultural chemicals as significant contributors. The annual average carbon emission was 276 000 tons in the Beijing farmland ecosystem, and decreased approximately 1.3 percent per year. The largest amount of carbon emissions came from agricultural chemicals at 85.4%, of which nitrogen fertilizer was the biggest contributor at 83.7%; （3） The carbon footprint also showed a decreasing trend along with an ecological surplus of carbon. The average carbon footprint was 5.71 hm^2 in the Beijing farmland ecosystem with decreasing rate at 5.5% annually; however, the carbon surplus showed a downward trend due to reduction in the amount of arable land; （4） Finally, the increasing carbon sink capacity led to higher carbon eeo-efficiency, with an annual average of 3.854 kg C·kg^-1 CE, carbon sequestration was greater than the amount of carbon released. In summary, the agro-ecosystem in suburban Beijing has sustained a relatively high carbon eco-efficiency, and agricultural production continues to have high sustainability potential.

关 键 词：北京市 农田生态系统 碳足迹 碳生态效率 碳源 碳汇 

分 类 号：X820.3[环境科学与工程—环境工程]