中文摘要：

【目的】研究不同施肥措施对潮土玉米植株碳同化物积累与分配的影响,为合理施肥和作物增产提供科学依据。【方法】以长期定位试验为基础,在玉米成熟期进行取样分析,研究不同施肥下玉米植株及器官的碳含量、碳同化物分配比例及碳氮比。【结果】长期有机无机配施（NPKM,1.5NPKM）下植株碳含量平均约为464g·kg-1,比偏施氮肥（N）与偏施磷钾肥（PK）处理的碳含量提高了3%左右。PK处理的碳同化物在茎叶中的分配比例约为57%,比最低的N处理高出了73%;在根茬中,PK处理的碳同化物分配比例也最高,高出N处理约为7%。但在籽粒中,PK处理的碳同化物分配比例最低,为30%。茎叶、穗轴、根茬的碳氮比,以PK处理为最高,1.5NPKM处理最低,前者比后者分别高121%、105%和120%。所有施肥处理中,玉米地上部分固碳量为NPKM处理最高,比CK处理高7.2t·hm-2;地下部分固碳量则以NPK处理平衡施肥最高,比CK处理高0.3t·hm-2。【结论】NPK配施及有机-无机肥配施能有效提高玉米植株的固碳量,提高碳同化物在玉米植株籽粒和穗轴中的分配比例,从而降低碳同化物在茎叶和根茬中的分配比例及其C/N,对土壤培肥和碳固定具有双重作用,是可持续和环境友好型的施肥模式。

英文摘要：

【Objective】 Study on the assimilated carbon accumulation and distribution of maize under various fertilizer applications in fluvio-aquic soil,can not only provide a scientific basis for rational fertilization practices for increasing crop yield,but it also has important significance to the study of global carbon cycling.【Method】 Based on a long-term experiment,samplings from various organs of maize were taken at maturity stage to measure the biomass yield under various fertilization applications.Organic carbon content,carbon assimilate distribution proportion,and C/N ratio of maize and its various organs under different fertilization conditions were also analyzed.【Result】 The results showed that the averaged carbon content in maize was about 464 g·kg-1 under the long term combined application of fertilizers and organic manure（NPKM,1.5NPKM）.It was 3% higher than the applications of N and PK treatments.The carbon content of maize kernel was obviously improved in the NK treatment,which was about 3% higher than the control treatment.In all treatments,the distribution proportion of assimilated carbon biomass in stem and leaf of maize was about 57% in PK treatment,which was 73% higher than that of the N treatment.The distribution proportion of assimilated carbon biomass in crop stubble in the PK treatment was also the highest（about 7%）.The distribution proportion of assimilated carbon biomass in maize grain under the PK treatment was the lowest（30%）.The C/N ratio in maize stem and leaf,cob,and crop stubble was the highest in PK treatment whereas it was the lowest under the 1.5NPKM treatment.The C/N ratio in stem and leaf,cob,and crop stubble in PK treatment was 121%,105% and 120% higher than that in the 1.5NPKM treatment,respectively.In all fertilization treatments,the fixed carbon content in whole maize was the highest in NPKM treatment in above-ground parts of maize,and that was the highest in NPK balanced fertilization treatment in under-ground parts of maize.The fixed carbon content of maiz