秸秆直接还田与炭化还田对潮土硝化微生物的影响  

Effect of Straw Return, Directly or as Biochar, on Nitrifying Microbes in Fluvo-aquic Soil

作　　者：李培培[1] 仝昊天 韩燕来[1] 姜瑛[1] 吴传发[1] LI Peipei;TONG Haotian;HAN Yanlai;JIANG Ying;WU Chuanfa(College of Resources and Environmental Sciences,Henan Agricultural University,Zhengzhou 450002,China)

机构地区：[1]河南农业大学资源与环境学院

出　　处：《土壤学报》2019年第6期1471-1481,共11页Acta Pedologica Sinica

基　　金：国家重点研发项目(2017YFD0301103);国家自然科学基金项目(41401273)共同资助~~

摘　　要：为比较秸秆直接还田和炭化还田对黄淮海平原小麦/玉米轮作体系典型潮土硝化作用及硝化微生物群落的影响,设置4个处理:全量小麦秸秆还田(S)、全量秸秆炭化还田(B)、半量秸秆半量生物质炭还田(SB)和不进行秸秆或生物质炭还田的对照(CK),连续进行3 a田间试验。对小麦、玉米两个生长季土壤理化性质进行分析,用末端限制性片段长度多态性(Terminal-restriction length polymorphism,T-RFLP)技术和克隆文库技术对氨氧化古菌(Ammonia-oxidizing archaea,AOA)和氨氧化细菌(Ammonia-oxidizing bacteria,AOB)群落结构和多样性进行分析。结果表明,在小麦季,与S处理相比,B处理显著降低了土壤容重,提高了土壤pH、有机碳(SOC)和速效钾(AK)含量(P<0.05),但并未显著影响土壤水分、铵态氮(NH^+4-N)和硝态氮(NO^-3-N)含量;B和SB处理的硝化潜势(Potential nitrification rate,PNR)分别为0.58、0.49μg·h^-1·g^-1(以NO^-2计,下同),显著高于CK,与S处理(0.40μg·h^-1·g^-1)差异不显著。玉米季,B处理显著提高了土壤水分、SOC和AK(P<0.05),各处理玉米季的PNR整体低于小麦季,B处理最高(0.27μg·h^-1·g^-1),显著高于CK和S处理(P<0.05)。小麦季PNR分别与AK、NH^+4浓度和土壤容重显著相关(P<0.05),与AOA和AOB群落组成均无显著关系;玉米季PNR仅与理化因子SOC显著相关,但该季节PNR与AOB群落结构显著相关。冗余分析(RDA)表明,土壤SOC、容重、pH和AK是显著影响硝化微生物群落结构的主要因子,对AOA和AOB群落结构总变异的解释量分别为76.4%和75.5%。系统发育树分析表明,AOA大部分属于土壤古菌Group1.1b,AOB多属于亚硝化螺菌Nitrosospira簇3。综上,与秸秆直接还田相比,炭化还田提高土壤硝化活性,改善部分土壤理化性质,引起土壤硝化微生物群落结构变化。【Objective】Biochar has increasingly been used as soil amendment to increase soil carbon storage and improve soil chemical and biological properties.However,so far little has been found in the literature talking comparatively about effects of returning maize stalk,directly or as biochar on soil properties,nitrification and ammonia oxidizer communities.【Method】A 3-year field experiment was conducted in a field of typical fluvo-aquic soil under the wheat/maize rotation-system commons in the North China Plain.The field experiment was designed to have four treatments:Treatment S(application of straw);Treatment B(application of straw-derived biochar);Treatment SB(half straw and half straw-derived biochar)and Treatment CK(no straw or biochar applied).Soil samples were collected in the wheat and maize seasons for analysis of soil properties and community structure and diversity of,ammonia oxidizing archaea and bacteria with the terminal restriction fragment length polymorphism(T-RFLP)and clone library techniques.【Result】It was found that during the wheat season Treatment B significantly enhanced soil pH,soil organic carbon(SOC)and readily available potassium(AK),while decreasing soil bulk density,but did not affect the contents of total nitrogen(TN),NO^-3-N or soil,water as compared to Treatment S,and PNR in Treatments B and SB was measured to be 0.58 and 0.49μg·h^-1·g^-1,respectively,significantly higher than that in CK(0.22μg·h^-1·g^-1),but did not differ much from that in Treatment S(0.40μg·h^-1·g^-1).During the maize season,Treatment B significantly increased soil water content,SOC and AK,and PNR on the whole was relatively lower in the maize season than in the wheat season,regardless of treatment,and much higher in Treatment B(0.27μg·h^-1·g^-1)than in Treatments CK and S(P<0.05).During the wheat season,Potential nitrification rate(PNR)was closely related to AK,+4 NH and soil bulk density(P<0.05),but not so to ammonia-oxidizing archaea(AOA)and ammonia-oxidizing bacteria(AOB)community structure

关 键 词：砂质潮土 氨氧化细菌 氨氧化古菌 秸秆直接还田 秸秆炭化还田 硝化作用 

分 类 号：S147[农业科学—肥料学] S154[农业科学—农业基础科学]