土壤学报2017，Vol.54Issue(6)：1547-1558,12.DOI:10.11766/trxb201706230077
不同轮作模式下氮肥用量对土壤有机氮组分的影响
Effects of Nitrogen Application Rate on Fractionation of Soil Organic Nitrogen Relative to Crop Rotation Mode
摘要
Abstract
A 3 a field experiment,consisting of 6 croppings,was conducted to investigate effects of N fertilizationon content and fractionation of soil organic N relative to N application rate and crop rotation mode,paddy/upland(rice/rapeseed,RR)rotation and upland(cotton/rapeseed,CR)rotation. Results show that after the 3 years of crop rotations cultivations,soil total N content in the 0~20 cm soil layer increased remarkably in plots more than 300 kg hm-2 in N input. Compared with CK(No N fertilization, N0-0),soil total N content increased by 13.6%~23.5% and 15.0%~23.0%,respectively,in the treatments 300 kg hm-2 and 375 kg hm-2 in N application rate under either RR or CR rotation. The increase in soil total acidolysable N content accounted for most of the increase in soil total N. Although no significant difference in soil total acidolysable N content was observed between plots under RR and CR rotations,fractionation of the soil acidolysable N varied between plots. The proportion of soil acidolysable ammonium N increased by 33.8% in the plots under RR rotation,much lower than that(53.9%)in the plots under CR rotation,but the increment of unidentified soil acidolysable N in proportion was higher in plots under RR rotation(36.0%) than that(16.6%)in the plots under CR rotation. To sum up,reasonable N fertilization may significantly increase soil organic N content. Fractionation of the soil organic N pool varies sharply between plots under RR and CR rotations. It is,therefore,of important significance to optimize N fertilization for high crop yield and high N utilization efficiency in the light of the characteristics of soil organic N transformation under different rotation systems.关键词
氮肥/水旱轮作/旱地轮作/全氮/土壤酸解态氮Key words
Nitrogen fertilizer/Paddy-upland rotation(RR)/Continuous upland rotation(CR)/Soil total N/Soil acidolysable nitrogen分类
农业科技引用本文复制引用
贾倩,廖世鹏,卜容燕,张萌,任涛,李小坤,丛日环,鲁剑巍..不同轮作模式下氮肥用量对土壤有机氮组分的影响[J].土壤学报,2017,54(6):1547-1558,12.基金项目
国家自然科学基金项目(41401324)和国家油菜产业技术体系建设专项(CARS-13)资助 Supported by the National Natural Science Foundation of China(No. 41401324)and the Earmarked Fund for China Agriculture Research System(No. CARS-13) （41401324）
