摘要
为了探索秸秆还田对不同深度土层土壤微生物多样性及群落构成.采用可培养方法、试剂盒酶活性测定方法和高通量测序技术,以 15 年秸秆还田定位试验土壤为研究对象,测定秸秆还田对小麦收获期 0～10、10～20 和 20～30 cm土层土壤微生物种群数量、酶活性以及细菌、真菌多样性和群落结构的影响.结果表明,长期秸秆还田增加了 3 个土层土壤酶活性和可培养微生物数量,0～10 cm土层的土壤脲酶、过氧化氢酶、蔗糖酶、碱性磷酸酶、纤维素酶活性以及细菌、真菌、氨化细菌、亚硝化细菌及纤维素降解菌的数量与对照差异显著(P<0.05);且秸秆还田的土壤酶活性和微生物数量效应随土壤深度的增加而降低.长期秸秆还田显著增加了 10～20 cm土层的细菌ACE指数、Chao1 指数、Shannon 指数等α多样性指数(P<0.05),改变了各土层土壤的细菌和真菌β多样性.另外,长期秸秆还田还改变了细菌和真菌的群落结构,且对细菌群落结构影响较大,0～10 cm土层中酸杆菌门(Acidobacteria)、变形菌门(Proteobacteria)、浮霉菌门(Planctomycetes)和Latesci-bacteria均显著增加(P<0.05).随着土壤深度的加深,细菌群落结构差异性越来越小.另外,秸秆还田能够使细菌群落间的相互作用连接更加紧密,但会降低真菌群落的稳定性.综上所述,长期秸秆还田对土壤酶活性、可培养微生物数量及细菌群落结构和多样性具有明显正向效应,且对土壤中细菌的积极影响更大.
Abstract
To explore the effects of straw returning on soil microbial diversity and community composition in different depths of soil layers,the effects of straw return on soil microbial population,enzyme activity,bacterial and fungal diversity,and community structure in 0-10,10-20,and 20-30 cm soil layers during the wheat harvest period were studied using cultivable methods,kit enzyme activity determination methods,and high-throughput sequencing techniques.The results showed that long-term straw returning increased soil enzyme activity and the number of cultivated microorganisms in all three soil layers.The activities of soil urease,catalase,sucrase,alkaline phosphatase,cellulase,as well as the number of bacteria,fungi,ammonifying bacteria,nitrobacteria,and cellulose degrading bacteria in 0-10 cm soil layers showed significant differences compared to the control(P<0.05).Moreover,the soil enzyme activity and microbial quantity effect of returning straw to the field decreased with the increase of soil depth.Long term straw returning significantly increased the α diversity index(P<0.05)of bacterial,namely ACE index,Chao1 index,Shannon index,etc.in the 10-20 cm soil layer,changed the β diversity of bacteria and fungi in each soil layer.In addition,long-term straw returning also changed the community structure of bacteria and fungi,and had a significant impact on the bacterial community structure.In the 0-10 cm soil layer,Acidobacteria,Proteobacteria,Planctomycotes,and Latescibacteria all significantly increased(P<0.05).As the soil depth deepened,the differences in bacterial community structure became smaller and smaller.In addition,returning straw to the field could make the interaction and connection between bacterial communities closer,but it reduced the stability of fungal communities.Long term straw returning to the field had a significant positive effect on soil enzyme activity,cultivable microbial quantity,bacterial community structure and diversity,and had a greater positive impact on bacteria in the soil.This study clarified the soil microecological effects of straw returning to the field,providing theoretical support for scientific straw returning to the field.
基金项目
国家重点研发计划(2021YFD1901004-5)
河北省农林科学院科技创新专项课题(2022KJCXZX-ZHS-10)
河北省现代农业产业技术体系(HBCT2021200208)
NETL
NSTL
万方数据