基于碳足迹角度的中国小麦生产可持续性评价

Assessment of wheat production sustainability in China based on carbon footprint analysis

为探究我国小麦生产碳足迹的时空动态,分析小麦生产的可持续性,本研究基于2005—2014年中国小麦生产的农资投入及产量数据,系统分析我国小麦生产的碳足迹、净碳吸收量与可持续性指数的变化。结果表明,2005—2014年,我国小麦生产系统表现为碳汇,小麦生产过程中化肥施用所造成的碳足迹最大,占总碳足迹的比例为55.25%~64.77%。2005—2014年随着小麦产量的提高,我国小麦生产的净碳吸收量逐年上升,生产过程中产生的温室气体排放对环境的影响逐年降低,可持续性指数逐年升高。小麦生产的碳足迹、净碳吸收量及可持续性指数与小麦产量之间存在着显著的相关性,每公顷小麦产量提高1 000kg,碳足迹增加434.20kg/hm^2(R^2=0.328,P<0.05),净碳吸收总量增加3.56×10~7 t(R^2=0.663,P<0.01),可持续性指数增加0.50(R^2=0.949,P<0.01)。分析小麦生产可持续性指数时间和空间上的动态变化发现,不同省份年际间差异显著,河北、安徽和湖北等省份小麦生产可持续性指数呈现出逐年上升的趋势,黑龙江、新疆和云南呈现逐年下降的趋势。采取合理的农作措施培肥土壤,提高地力,合理减少化肥使用,提高灌溉效率,提高小麦生产的可持续性,有利于应对和缓解气候变化。

To explore the temporal and spatial dynamics of carbon footprint and analysis the sustainability of wheat production in China.A study was conducted to assess the carbon footprint（CF）and sustainability index of wheat production in China using statistical data from 2005-2014.The result showed that wheat field was a sink of carbon.Among the inventories,the input of fertilizer emitted the most greenhouse gases（GHGs）of wheat production occupied about 55.25%-64.77% of the total CF.Additionally,significant increases in net carbon sequestration and sustainability index were observed with increases in wheat production from 2005 to 2014.Furthermore net carbon sequestration,CF per area,and sustainability index could be enhanced by 3.56×10^7 t（R^2=0.663,P〈0.01）434.2 kg/hm^2（R^2=0.328,P〈0.05）and 0.50（R^2=0.949,P〈0.01）respectively when wheat production increased every 1 000 kg.Therefore,improving wheat production could promote the carbon sink capacity of wheat filed.Obvious spatial differences of sustainability index in China indicated a rising trend in Hebei,Anhui,Hubei and Shanxi provinces,and a moderating trend in Heilongjiang,Xinjiang,Yunnan.The environmental impacts from GHG emission onwheat production were alleviated recent years.Strategies were put forwarded to enhance soil fertility and sustaining agriculture in wheat production,including proper use of agricultural materials（i.e.,irrigation and chemical fertilizer inputs）for wheat production in China,which could make a certain contribution to energy saving and emission reduction,and consequently enhance sustainability and mitigate climate change.