不同碳氮比有机肥对植烟黄壤氮素的影响

Effects Organic Manures with Different C-N ratio on Nitrogen in Tobacco-growing Yellow Soil

为了解不同有机肥碳氮比（C/N）对植烟黄壤氮素含量及形态的影响,采用田间试验方法,进行不同碳氮比有机肥（腐熟猪粪和秸秆）植烟土壤施肥试验。结果表明：不同碳氮比有机肥均对土壤氮素具有明显的缓释作用,但对氮素形态的影响差异较大,C/N越高,土壤氮含量降低越慢,C/N越低,土壤氮释放速度越慢;有机肥处理相对于纯化肥处理土壤全氮含量提高7.48%~14.97%,提高最多的是碳氮比为25∶1的猪粪＋秸秆;C/N为纯猪粪的处理施肥后30天铵态氮含量最高,达24.41mg/kg,30~120d时明显降低,表现为纯猪粪（12.8∶1）〉猪粪＋秸秆（25∶1）〉猪粪＋秸秆（15∶1）〉猪粪＋秸秆（35∶1）〉纯秸秆（67.3∶1）〉对照;在第30d,纯猪粪处理的植烟土壤硝态氮含量最高,纯秸秆处理的硝态氮含量最低,移栽后60d,处理间硝态氮含量差异显著,纯猪粪处理最高。

To explore the effects of organic manures with different C-N ratio on nitrogen in tobaccogrowing yellow soil,a field experiment was conducted to explore the fertilizing effects of organic manures with different C-N ratio（decomposed pig manure and straw）in tobacco-growing yellow soil.Results：Organic manures with various C-N ratio had obvious sustained-release effects on soil nitrogen,while the effects on nitrogen forms varied greatly.The higher the C-N ratio,the slower the decreasing of soil nitrogen content.The lower the C-N ratio,the slower the N release rate;The total nitrogen content of organic manure treatments enhanced by 7.48~14.97% compared with chemical fertilizer treatment,the treatment of pig manure＋straw（C-N 25∶1）enhanced the most;Ammonium nitrogen content of pure pig manure treatment reached the highest,24.41 mg/kg,after applying for 30 days,and significantly decreased during 30~120d,followed the sequence of pure pig manure（12.8∶1）pig manure ＋straw（25∶1）pig manure＋straw（15∶1）pig manure＋straw（35∶1）straw（67.3∶1）CK;On the 30 th later,nitrate nitrogen concentration of pure pig manure treatment reached the highest,while that of pure straw treatment reached the lowest.60 days later,nitrate nitrogen concentration of different treatments varied significantly and pure pig manure treatment was of the highest content.