秸秆还田下不同追氮量对麦田土壤真菌群落结构和生态网络的影响  

Effects of Different Topdressing Nitrogen Rates on Soil Fungal Community Structure and Ecological Network in Wheat Field Under Crop Residue Retention

作　　者：靳海洋 闫雅倩 张德奇[1] 杨程[1] 岳俊芹[1] 李向东[1] 邵运辉[1] 方保停[1] 王汉芳[1] 秦峰[1] JIN Hai-yang;YAN Ya-qian;ZHANG De-qi;YANG Cheng;YUE Jun-qin;LI Xiang-dong;SHAO Yun-hui;FANG Bao-ting;WANG Han-fang;QIN Feng(Henan Province Engineering Research Center of Wheat Yield-Quality Simultaneous Improvement,Scientific Observing and Experimental Station of Crop Cultivation in Central Plain,Ministry of Agriculture and Rural Affairs,Wheat Research Institute,Henan Academy of Agricultural Sciences,Zhengzhou 450002,China;Co-construction State Key Laboratory of Wheat and Maize Crop Science,College of Agronomy,Henan Agricultural University,Zhengzhou 450002,China)

机构地区：[1]河南省农业科学院小麦研究所,农业农村部中原地区作物栽培科学观测实验站,河南省小麦产量-品质协同提升工程研究中心,郑州450002 [2]河南农业大学农学院,省部共建小麦玉米作物学国家重点实验室,郑州450002

出　　处：《环境科学》2023年第2期1085-1094,共10页Environmental Science

基　　金：中原科技创新领军人才计划项目(224200510028);国家重点研发计划项目(SQ2020YFF0426480);河南省现代农业产业技术体系建设专项(HARS-22-01-G5);河南省农业科学院科技创新团队项目。

摘　　要：秸秆还田和肥料施用是农田土壤养分输入的主要来源,秸秆还田条件下配合适宜的化肥施用量能够在环境友好的前提下为作物生产提供必要的营养.为明确秸秆还田条件下不同追氮量对麦田土壤真菌群落的影响,从土壤生态功能角度评估冬小麦氮肥管理措施的合理性.在秸秆全量还田基施氮肥150 kg·hm^(-2)基础上,多年定位设置5个追氮量(0、 37.5、 75、 112.5和150 kg·hm^(-2))处理,采用实时荧光定量PCR和高通量测序技术分析冬小麦成熟期土壤真菌群落丰度、多样性、结构和生态网络,探讨驱动土壤真菌群落变化的主要土壤理化因子.结果表明,和不追施氮肥和低追氮量处理相比,高追氮量处理增加了土壤全氮和无机氮含量,降低了土壤pH值、全磷、有效磷和速效钾含量.和不追施氮肥处理相比,追氮量37.5~150 kg·hm^(-2)处理显著增加了土壤真菌群落丰度(P<0.05),而追施氮肥各处理间差异未达显著水平(P>0.05).土壤真菌群落Heip指数和Shannon指数随追氮量的增加逐渐降低,追氮量150 kg·hm^(-2)处理的土壤真菌群落Sobs、 Heip和Shannon指数显著低于追氮量0~75 kg·hm^(-2)处理(P<0.05).主成分分析和相似性分析表明,不同追氮量处理的土壤真菌群落结构存在显著差异(P<0.05).随着追氮量的增加,土壤真菌群落生态网络边数和平均邻节数呈先增加再减少的趋势,追氮量37.5 kg·hm^(-2)处理的网络复杂度最高;和追氮量0~75 kg·hm^(-2)处理相比,追氮量112.5 kg·hm^(-2)和150 kg·hm^(-2)处理增加了土壤真菌群落生态网络的特征路径长度,降低了网络密度.随着追氮量的增加,土壤腐生营养型真菌的相对丰度逐渐增加,病理-腐生-共生营养型土壤真菌的相对丰度逐渐降低.冗余分析表明土壤pH值、全磷、无机氮、有效磷和速效钾含量是影响不同追氮量处理下麦田土壤真菌群落结构的主要土壤理化因子.综上所述,在秸秆还�Crop residue retention and fertilizer application are the main sources of soil nutrient input in fields.Crop residue retention combined with appropriate fertilizer application rates could provide necessary nutrients for crop production under the premise of environmentally friendly conditions.The aim of this study was to clarify the influence of different topdressing nitrogen rates on the soil fungal community in a wheat field under crop residue retention and to evaluate the rationality of nitrogen fertilizer management in winter wheat from the perspective of soil ecological function.On the basis of full straw retention and 150 kg·hm^(-2) basal nitrogen,treatments with five topdressing nitrogen rates(0,37.5,75,112.5,and 150 kg·hm^(-2)) were set up.The abundance,diversity,structure,and ecological network of soil fungal communities were analyzed using real-time fluorescence quantitative PCR and high-throughput sequencing,and the main soil physical and chemical factors driving the change in soil fungal communities were explored.The results showed that,compared with the no topdressing nitrogen and low topdressing nitrogen rate treatments,high topdressing nitrogen rate treatments increased soil total nitrogen and mineral nitrogen and decreased soil pH,total phosphorus,available phosphorus,and available potassium.Compared with the no topdressing nitrogen treatments,the 37.5-150 kg·hm^(-2) topdressing nitrogen treatments significantly increased soil fungal community abundance(P0.05).The Heip index and Shannon index of soil fungal communities decreased gradually with the increase in topdressing nitrogen rate,and the Sobs index,Heip index,and Shannon index of soil fungal communities in the treatment with 150 kg·hm^(-2) topdressing nitrogen were significantly lower than those of 0-75 kg·hm^(-2) topdressing nitrogen treatments(P<0.05).Principal component analysis and similarity analysis showed that there were significant differences in soil fungal community structure under different topdressing nitrogen rate treatments(

关 键 词：秸秆还田 氮肥 冬小麦 土壤 微生物群落 

分 类 号：X172[环境科学与工程—环境科学]