不同有机肥替代20%化肥氮的稻田土壤有机氮组分积累特征
Accumulation Characteristics of Organic Nitrogen Fractions in Paddy Soil upon Replacement of 20%Chemical Nitrogen Fertilizer with Different Organic Fertilizers
刘华 1彭复细 2陈俊 2林娇 2周玉安 2Nader Saad 2张振华 2夏银行2
作者信息
- 1. 湖南省慈利县农业农村局,湖南 慈利 427200
- 2. 湖南农业大学资源学院,湖南 长沙 410128;岳麓山实验室,湖南 长沙 410128
- 折叠
摘要
为了探明不同有机肥等比例替代化肥下土壤有机氮各组分积累特征,依托长期施肥定位试验,以不施氮肥(CK)和施用化肥氮(NPK)为对照,检测分析了猪粪(PM)、商品有机肥(OM)和早稻紫云英+晚稻水稻秸秆(RMS)替代 20%化肥氮处理下土壤有机氮组分含量及其占全氮的比例.结果表明:全氮和有机氮组分含量在NPK和CK处理之间差异不明显;与NPK处理相比,有机肥替代化肥各处理的土壤全氮含量提高了5.2%～8.5%,尤其是PM处理;且3种有机肥替代化肥的酸解氨基酸氮、酸解铵态氮和酸解氨基糖氮的含量分别显著提高了11.0%～18.8%、10.8%～18.5%和16.7%～31.1%,其占全氮比例分别提高了4.4%～11.1%、2.1%～12.6%和7.5%～24.5%,增加了土壤速效氮含量,尤其是RMS处理;其原因可能是有机肥替代化肥不同程度地增加了微生物生物量碳氮,增强了氮转化相关酶活性,促进了难分解有机氮组分向易分解有机氮组分的转化.综上,有机肥等比例替代化肥均能有效提高土壤氮素积累和供应,其中猪粪更有利于氮素积累,秸秆更有利于增强氮素供应潜力.
Abstract
This study aims to unveil the accumulation characteristics of soil organic nitrogen(N)fractions upon replacement of chemical fertilizer with organic fertilizer at the same proportion based on a long-term fixed-location fertilization experiment.With no N fertilizer(CK)and chemical N fertilizer(NPK)as the control groups,we measured the content and proportions of organic N fractions in total N under three replacement treatments:pig manure replacing 20%chemical N fertilizer(PM),commercial organic fertilizer replacing 20%chemical N fertilizer(OM),and Chinese milk vetch in early rice and rice straw in late rice replacing 20%chemical N fertilizer(RMS).The results indicated that the content of total N and organic N fractions presented no significant differences between NPK and CK.Compared with NPK,the three replacement treatments increased soil total N content by 5.2%-8.5%,with the highest increase in the PM treatment.The three replacement treatments increased the content of acid-hydrolyzed amino acid N,acid-hydrolyzed ammonium N,and acid-hydrolyzed amino sugar N by 11.0%-18.8%,10.8%-18.5%,and 16.7%-31.1%,respectively.Meanwhile,the three treatments increased the proportions of the three organic N fractions above in total N by 4.4%-11.1%,2.1%-12.6%,and 7.5%-24.5%,respectively.The data suggested that the replacement treatments,especially RMS,increased the available N in soil.Possible causes of these results were that organic fertilizer replacing chemical fertilizer increased the contents of microbial biomass C and N,as well as the activity of N-related enzymes,and promoted the conversion of difficultly decomposable oragnic N fractions into easily decomposable organic N fractions.In summary,replacing chemical N fertilizer with different organic fertilizers at the same proportion can effectively increase the accumulation and supply of soil N.Pig manure and straw are conducive to N accumulation and supply,respectively.
关键词
等比例替代/有机氮组分/微生物生物量/酶活性/稻田土壤Key words
replacement at the same proportion/organic nitrogen fractions/microbial biomass/enzyme activity/paddy soil引用本文复制引用
出版年
2024
国家科技期刊平台
NSTL
万方数据