Greenhouse gas(GHG)emissions and reactive nitrogen(Nr)releases are central environmental problems,which are closely linked to climate change,environmental ecology and crop production.Sustainable development of agricul...Greenhouse gas(GHG)emissions and reactive nitrogen(Nr)releases are central environmental problems,which are closely linked to climate change,environmental ecology and crop production.Sustainable development of agriculture plays an important role in GHG emissions and Nr loss.The life cycle assessment(LCA)method was used to calculate the product and farm carbon footprints(CFs)and nitrogen footprints(NFs)in rice,wheat and maize production in China based on farm survey data.The results pinpointed that the CFs of rice,wheat and maize were 0.87,0.30 and 0.24 kg/kg.Meanwhile,the computed NFs were 17.11,14.26 and 6.83 g/kg,respectively.Synthetic nitrogen fertilizer applications and methane(CH4)emissions were dominant CF sources,while ammonia(NH3)volatilization was the main NF contributor.Moreover,significant decreases in CF and NF by 20%–54%and 33%–61%,respectively,were found in large-size farms(>20 hm^(2))when compared to small-size farms(<0.7 hm^(2)).Furthermore,the significantly positive relationships between CF and NF indicated the potential for simultaneous mitigation in the regions with high agricultural inputs,like amounts of fertilizer.Based on our results,some effective solutions would be favorable toward mitigating climate change and eutrophication of the major cereal crop production in China,especially optimizing fertilizer use and farm machinery operation efficiencies,as well as developing large-size farms with intensive farming.展开更多
为改善传统N-Calculator模型的局限性,加强食物氮足迹核算结果与环境影响的联系,提高活性氮管理预见性,将N-Calculator模型与食物系统养分流动(Nutrient Flows in Food Chains,Environment and Resources Use,NUFER)模型进行耦合,以估...为改善传统N-Calculator模型的局限性,加强食物氮足迹核算结果与环境影响的联系,提高活性氮管理预见性,将N-Calculator模型与食物系统养分流动(Nutrient Flows in Food Chains,Environment and Resources Use,NUFER)模型进行耦合,以估算我国2001—2020年人均食物氮足迹,建立组合预测体系。结果显示:2001—2020年,我国人均食物氮足迹由16.04 kg N/a增至18.95 kg N/a;全国食物氮足迹由20.47 Mt N/a增至26.76 Mt N/a;居民饮食结构正由以植物源食物为主的低氮消费模式转向以动物源食物为主的高氮消费模式;食物生产过程产生的活性氮的最终归宿为大气(64.3%)、水体和深层土壤(35.7%);我国食物氮足迹与人均可支配收入、城市化率、动物源食物消费氮占比呈正相关性,与恩格尔系数呈负相关性;未来10 a我国人均食物氮足迹呈增长趋势,预测结果显示年均增幅为0.16 kg N/a。展开更多
基金supported by the Natural Science Foundation of Zhejiang Province,China(Grant No.LQ21C130002)the Engineering Science and Technology Development Strategy Consulting and Research Project of China(Grant No.Js2019-zd01)the Central Public-Interest Scientific Institution Basal Research Fund of China(Grant No.CPSIBRF-CNRRI-202130)。
文摘Greenhouse gas(GHG)emissions and reactive nitrogen(Nr)releases are central environmental problems,which are closely linked to climate change,environmental ecology and crop production.Sustainable development of agriculture plays an important role in GHG emissions and Nr loss.The life cycle assessment(LCA)method was used to calculate the product and farm carbon footprints(CFs)and nitrogen footprints(NFs)in rice,wheat and maize production in China based on farm survey data.The results pinpointed that the CFs of rice,wheat and maize were 0.87,0.30 and 0.24 kg/kg.Meanwhile,the computed NFs were 17.11,14.26 and 6.83 g/kg,respectively.Synthetic nitrogen fertilizer applications and methane(CH4)emissions were dominant CF sources,while ammonia(NH3)volatilization was the main NF contributor.Moreover,significant decreases in CF and NF by 20%–54%and 33%–61%,respectively,were found in large-size farms(>20 hm^(2))when compared to small-size farms(<0.7 hm^(2)).Furthermore,the significantly positive relationships between CF and NF indicated the potential for simultaneous mitigation in the regions with high agricultural inputs,like amounts of fertilizer.Based on our results,some effective solutions would be favorable toward mitigating climate change and eutrophication of the major cereal crop production in China,especially optimizing fertilizer use and farm machinery operation efficiencies,as well as developing large-size farms with intensive farming.
文摘为改善传统N-Calculator模型的局限性,加强食物氮足迹核算结果与环境影响的联系,提高活性氮管理预见性,将N-Calculator模型与食物系统养分流动(Nutrient Flows in Food Chains,Environment and Resources Use,NUFER)模型进行耦合,以估算我国2001—2020年人均食物氮足迹,建立组合预测体系。结果显示:2001—2020年,我国人均食物氮足迹由16.04 kg N/a增至18.95 kg N/a;全国食物氮足迹由20.47 Mt N/a增至26.76 Mt N/a;居民饮食结构正由以植物源食物为主的低氮消费模式转向以动物源食物为主的高氮消费模式;食物生产过程产生的活性氮的最终归宿为大气(64.3%)、水体和深层土壤(35.7%);我国食物氮足迹与人均可支配收入、城市化率、动物源食物消费氮占比呈正相关性,与恩格尔系数呈负相关性;未来10 a我国人均食物氮足迹呈增长趋势,预测结果显示年均增幅为0.16 kg N/a。
