秸秆还田对玉米根际氨氧化微生物群落及红壤硝化潜势的影响  

Effects of straw returning on the ammonia-oxidizers and nitrification in the rhizosphere of maize in a red soil

作　　者：郑洁 程梦华 栾璐 孔培君 孙波[1] 蒋瑀霁[1] ZHENG Jie;CHENG Menghua;LUAN Lu;KONG Peijun;SUN Bo;JIANG Yuji(State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;University of Chinese Academy of Sciences,Beijing 100049,China;College of Life Science,Nanjing Normal University,Nanjing 210023,China)

机构地区：[1]土壤与农业可持续发展国家重点实验室(中国科学院南京土壤研究所),南京210008 [2]中国科学院大学,北京100049 [3]南京师范大学生命科学学院,南京210023

出　　处：《生态学报》2022年第12期5022-5033,共12页Acta Ecologica Sinica

基　　金：国家自然科学基金优秀青年基金项目(41922048);国家自然科学基金面上项目(42177298,41771297)。

摘　　要：为探讨酸性红壤根际氨氧化微生物群落以及硝化作用对不同秸秆还田处理的响应,基于中国科学院鹰潭红壤生态实验站设置的秸秆还田长期试验平台(9年),采用荧光定量PCR和高通量测序技术,研究不同秸秆还田处理(不施肥(CK);氮磷钾肥(NPK);氮磷钾肥+秸秆(NPKS);氮磷钾肥+秸秆猪粪配施(NPKSM);氮磷钾肥+秸秆生物炭(NPKB))下玉米根际土壤氨氧化古菌(ammonia⁃oxidizing archaea,AOA)和细菌(ammonia⁃oxidizing bacteria,AOB)丰度和群落结构的变化,揭示了秸秆还田对根际氨氧化微生物群落结构和硝化潜势(potential nitrification activity,PNA)的影响机制。结果发现:相比CK和NPK处理,秸秆还田显著提高了土壤养分含量和硝化潜势,其中有机碳(SOC)、全氮(TN)、全磷(TP)、速效磷(AP)、速效钾(AK)、硝态氮(NO^(-)_(3)⁃N)和铵态氮(NH^(+)_(4)⁃N)含量显著增加,NPKSM处理对土壤肥力提升效果最佳。AOA的硝化潜势显著高于AOB,表明AOA主导了土壤硝化作用。秸秆还田显著提高了AOA和AOB丰度,改变了群落组成,Shannon和Chao1指数均高于未添加秸秆的处理。SOC、TN和NH^(+)_(4)⁃N以及AOA和AOB多样性指数分别与PNA_(AOA)和PNA_(AOB)呈显著正相关。结构方程模型表明,NH^(+)_(4)⁃N和TN通过AOA丰度和AOB多样性间接影响PNA_(total)。研究结果表明,秸秆还田处理能够显著提高红壤肥力,增加红壤AOA和AOB数量和活性,从而促进红壤氮素转化过程,其中秸秆猪粪配施的提升效果最佳。In the present study,a 9⁃year field experiment was conducted to investigate the effects of straw returning on the rhizosphere ammonia⁃oxidizers and nitrification in a red soil.The field experiment included five treatments:no fertilizer,CK;chemical nitrogen,phosphorous and potassium fertilizer,NPK;NPK fertilizer and straw,NPKS;NPK fertilizer and straw combined with pig manure,NPKSM;NPK fertilizer and straw biochar,NPKB,which was located at the National Agro⁃Ecosystem Observation and Research Station in Yingtan.Here,the abundance and composition of ammonia⁃oxidizing archaea(AOA)and bacteria(AOB)in the rhizosphere of maize under different types of straw returning were examined by quantitative PCR and Illumina sequencing.The results found that the straw returning treatments significantly increased soil nutrient contents and potential nitrification activity(PNA)compared with the CK and NPK treatments,with the highest soil organic carbon(SOC),total nitrogen(TN),total phosphorus(TP),available phosphorus(AP),available potassium(AK),nitrate nitrogen(NO^(-)_(3)⁃N),ammonium nitrogen(NH^(+)_(4)⁃N)and PNA under the NPKSM treatments.AOA⁃specific PNA(PNA_(AOA))was significantly higher than AOB⁃specific PNA(PNA_(AOB)),which indicated that AOA dominated the nitrification in a red soil.The straw returning treatments presented significantly higher abundance and diversity(Shannon and Chao1 indices)of AOA and AOB community than the treatments without straw returning.Furthermore,the straw returning treatments significantly shaped the composition of AOA and AOB community.SOC,TN,NH^(+)_(4)⁃N,as well as AOA and AOB diversity were significantly correlated with PNA_(AOA)and PNA_(AOB),respectively.Structural equation modelling showed that NH^(+)_(4)⁃N and TN indirectly affected PNA_(total)through the AOA abundance and AOB diversity.The results indicated that straw returning treatments could improve the abundance and activities of AOA and AOB community,and consequently promoted the process of nitrogen transformation,with

关 键 词：秸秆还田处理 氨氧化古菌 氨氧化细菌 硝化潜势 红壤 

分 类 号：S154.3[农业科学—土壤学]