东北地区玉米种植系统碳足迹及氮足迹研究

Carbon Footprint and Nitrogen Footprint of Maize Planting System in Northeast China

以东北玉米产区为主要研究对象,研究了东北地区玉米种植系统的碳足迹与氮足迹,以实现降低该地区农业生产碳、氮排放的同时粮食平稳增产。基于生命周期法(LCA)研究了2019年东北地区玉米种植系统中产生的温室气体及活性氮排放量及构成因素,并结合调研数据分析不同省份间施氮量对碳、氮足迹的影响。结果表明:东北地区玉米种植系统单位面积、单位产量和单位净现值碳足迹均值分别为2953.8 kg/hm^(2),0.34 kg/kg和0.26 kg/元,单位面积、单位产量和单位净现值氮足迹均值分别为84.3 kg/hm^(2),9.6 kg/kg,0.01 kg/元;由于不同省份玉米生产条件差异,其碳足迹存在较大差别,单位面积碳足迹与单位产量碳足迹同步,表现为黑龙江省最高(3208.6 kg/hm^(2),0.37 kg/kg),吉林省居中(2930.2 kg/hm^(2),0.32 kg/kg),辽宁省最低(2722.8 kg/hm^(2),0.31 kg/kg);玉米生产的氮足迹为辽宁省最高(102.1 kg/hm^(2),12.1 kg/kg),吉林省最低(69.4 kg/hm^(2),7.5 kg/kg)。东北地区玉米生产碳足迹组成中占比最大的部分为肥料施用产生CO_(2)和N_(2)O,达76%,机械耗油导致的温室气体排放占13%,而氮足迹主要排放源为NH3挥发(40%)和硝态氮淋洗(51%)产生的氮排放。总体来看,优化氮肥投入及提高机械化生产率是降低农业生产的碳、氮排放的重要途径,而针对东北地区,不同的生态环境特点仍需因地制宜地制定减排措施,实现农业可持续发展。

Taking the maize production area in Northeast China as the main research object,carbon footprint and nitrogen footprint of maize planting system in Northeast China were studied to realize the reduction of carbon and nitrogen emissions of agricultural production,and the increment of stable grain yield.Based on life cycle analysis(LCA),we carried out research on greenhouse gas and active nitrogen emissions generated in maize planting system in Northeast China and their components in 2019.Combined with the survey data,we analyzed the impacts of nitrogen application rates on carbon and nitrogen footprints among different provinces.The results show that unit area,unit yield and unit net present value of carbon footprint average values of maize planting system in Northeast China are respectively 2953.8 kg/hm^(2),0.34 kg/kg and 0.26 kg/yuan.And unit area,unit yield and unit net present value of nitrogen footprint average values are respectively 84.3 kg/hm^(2),9.6 kg/kg and 0.01 kg/yuan.Due to differences in production conditions,carbon footprint of different provinces varies significantly,and carbon footprint per unit area is synchronized with carbon footprint per unit yield,the highest in Heilongjiang province(3208.6 kg/hm^(2),0.37 kg/kg),the middle in Jilin province(2930.2 kg/hm^(2),0.32 kg/kg),and the lowest in Liaoning province(2722.8 kg/hm^(2),0.31 kg/kg).Nitrogen footprint is the highest in Liaoning province(102.1 kg/hm^(2),12.1 kg/kg),and the lowest in Jilin province(69.4 kg/hm^(2),7.5 kg/kg).In the composition of carbon footprint of maize production in Northeast China,CO_(2)and N_(2)O generated by fertilizer application take the most proportion,reaching 76%,and greenhouse gas emissions caused by mechanical oil consumption account for 13%.The main emission sources of nitrogen footprint are NH3 volatilization(40%)and nitrate nitrogen leaching(51%).In general,optimizing nitrogen fertilizer input and improving mechanized productivity are important ways to reduce carbon and nitrogen emissions from agricultural production.For the Northeast area,different ecological environment characteristics still require tailored emission reduction measures to achieve sustainable agricultural development.