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秸秆与木本泥炭短期施用对潮土有机质及微生物群落组成和功能的影响*

2020-02-20赵文慧徐基胜张佳宝赵炳梓

土壤学报 2020年1期
关键词:泥炭群落秸秆

赵文慧,马 垒,徐基胜,谭 钧,张佳宝,赵炳梓†

秸秆与木本泥炭短期施用对潮土有机质及微生物群落组成和功能的影响*

赵文慧1,2,马 垒1,2,徐基胜1,谭 钧3,张佳宝1,赵炳梓1†

(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. 北京中向利丰科技有限公司,北京 100004)

直接添加富含腐殖物质的木本泥炭可快速提升土壤有机碳含量,但其与常规施用秸秆相比的效应如何尚不清楚。通过设置不添加物料(CK)、施用秸秆(R)、施用木本泥炭(MT)、秸秆还田和木本泥炭联合施用(RMT)四个田间试验处理,经过一季玉米生长后比较不同处理对玉米产量、土壤肥力、细菌群落组成和功能的影响。结果表明,R和RMT处理的地上生物量与CK无显著差异,而在玉米整个生育期的平均呼吸速率则分别较CK高40%和64%;MT处理的地上生物量较CK低10%,但MT和CK的平均呼吸速率无显著差异。另一方面,R处理的土壤有机质(SOM)含量与CK无显著差异,而MT和RMT处理的SOM含量则较CK分别高79%和56%。基于主成分分析和功能预测发现,与CK处理比,R处理分解利用新鲜秸秆的绿弯菌门、芽单胞菌门、节细菌属、指孢囊菌属和显著增多,而化能异养、需氧化能异养、尿素代谢功能显著降低;MT处理降解大分子有机物的土壤杆菌属纤维菌属、德沃斯氏菌属、农研丝杆菌属、类诺卡氏菌属和显著增多,需氧化能异养功能显著降低,纤维素代谢功能显著升高;而RMT处理与CK群落组成和功能类似。因此,在潮土区单独施用MT尽管能迅速提升SOM含量,但可能导致短期内作物产量降低,而R和MT联合施用在迅速提升SOM的同时可提高土壤呼吸,维持稳定的微生物群落和功能。

秸秆还田;木本泥炭;高通量测序;微生物群落;功能预测

土壤有机质是土壤肥力的重要指标,是影响黄淮海平原潮土区作物产量高低的决定性因子之一[1]。黄淮海平原典型潮土是由河流冲积物受地下水运动和耕作活动影响而形成,砂粒含量高、土壤结构差、土壤微生物活动强烈,使得土壤有机质含量低且难以积累[2]。因此,如何促进潮土土壤有机质积累是提升潮土生产力的关键所在[3]。

秸秆作为农业生产的主要副产品,含有丰富的有机碳,是一类重要的能直接利用的可再生生物资源,因此,秸秆还田是提高作物产量和土壤有机质的重要途径[4]。但利用秸秆还田提升土壤有机质通常需要冗长过程,在黄淮海平原潮土区,即使连续18 a配施化肥和秸秆,土壤有机质含量也仅有12.10 g·kg–1[5],不能达到当地高产区土壤有机质水平[6]。研究表明,小麦秸秆在黄潮土中一年后腐殖化系数为25.80%[7],因此,较低的秸秆腐殖化程度不利于土壤有机质快速累积。

木本泥炭是由木本植物残体在水分过多、通气不良、气温较低的沼泽环境中,经过长期累积而形成的一种不易分解、稳定的有机物堆积层。其具有有机质和腐殖酸含量高、纤维素丰富、疏松多孔、比表面积大、保水保肥能力强等优点[8]。腐殖物质是土壤有机质的重要组成部分[9],由于其表面含有羧基、酚羟基和醇羟基等含氧官能团,能够与土壤中养分离子发生相互作用,影响土壤养分吸附、释放[10]。腐殖物质也能与黏土矿物结合形成有机无机复合体,促进土壤团聚体的形成和稳定,对土壤物理化学及生物性状有重要影响[11]。木本泥炭施用还能够提高土壤碳库管理指数,提高土壤团聚体的稳定性[12]。有研究表明,土壤有机质含量与作物产量存在显著正相关关系[3],因而预测在土壤中直接施用木本泥炭可能会在短期内快速提升土壤有机质含量,从而有可能快速提高瘠薄潮土上作物的产量,但其效应如何、与直接秸秆还田相比是否具有优越性等问题尚不清楚。

本研究通过田间试验,在河南封丘典型潮土区设置不添加物料(CK)、秸秆还田(R)、木本泥炭(MT)以及秸秆还田+木本泥炭(RMT)四个处理,其中,R和MT为等碳量施用。主要研究目的包括:(1)明确秸秆和木本泥炭等碳量单独施用条件下对作物产量和土壤肥力的影响;(2)明确秸秆和木本泥炭联合施用的叠加效应;(3)基于高通量分析明确不同处理对土壤细菌群落结构和组成的影响。旨在为潮土区土壤地力提升、作物增产提供理论依据和科学支持。

1 材料与方法

1.1 试验概况

试验地位于河南省封丘农田生态系统国家野外科学观测研究站内(35°00′N,114°24′E)。该地位于黄河北岸,属半干旱、半湿润的暖温带季风气候,年均气温13.9℃,年均降水量为605 mm,土壤类型为潮土,种植模式为冬小麦—夏玉米轮作。试验开始前耕层土壤基础化学性质为:pH 8.66,有机质5.76 g·kg–1,全氮0.55 g·kg–1,有效磷 6.51 mg·kg–1,速效钾96.92 mg·kg–1。

试验于2016年玉米季开始,共设4个处理:(1)不施用有机物料(CK);(2)秸秆还田(R);(3)木本泥炭(MT);(4)秸秆还田+木本泥炭(RMT)。每个处理3个重复,共12个小区,每个小区面积为6 m×8 m。玉米播种期为2016年6月10日,种植密度为每公顷67 000株,行距为60 cm,株距为25 cm。有机物料在玉米播种前施用,R和MT处理为等碳量施用,秸秆施用量为7 500 kg·hm–2,木本泥炭施用量为7 005 kg·hm–2;RMT处理秸秆施用量为7 500 kg·hm–2,木本泥炭施用量为7 005 kg·hm–2。4个处理化肥施用量相同,即N 225.0 kg·hm–2,P2O5134.4 kg·hm–2,K2O 120.0 kg·hm–2。氮肥用尿素(CO(NH2)2),磷肥用磷酸二铵((NH4)2HPO4),钾肥用硫酸钾(K2SO4),其中,40%氮肥作为基肥施入,60%作为追肥在玉米拔节期施入,磷钾肥均作为基肥施入。

供试玉米品种为登海605,购自山东登海种业股份有限公司。供试木本泥炭购自北京利丰公司,木本泥炭有机碳含量为482.8 g·kg–1,全氮、全磷和全钾含量分别为10.77 g·kg–1、0.77 g·kg–1和2.72 g·kg–1。秸秆为上季小麦秸秆,有机碳含量为450.9 g·kg–1,全氮、全磷和全钾含量分别为6.51 g·kg–1、0.51 g·kg–1和15.04 g·kg–1。

1.2 样品采集与分析

玉米籽粒和地上部生物量于玉米收获期测定,每个小区选择4 m2的面积,将果穗与茎秆分开晒干,测定籽粒产量和茎秆产量,地上部生物量为籽粒产量与茎秆产量之和。土壤样品于2016年9月玉米收获期采集。按照S采样法,每个小区使用直径5 cm的土钻采集5份0~20 cm土样,混合成一个样品。所有样品置于冰袋中运回实验室。去除植物根系和石块后过2 mm筛混匀,样品分为三部分,一部分风干后用于土壤理化性质的测定,一部分置于–20℃用于测定硝态氮含量,一部分置于–80℃用于土壤DNA提取。

在玉米全生育期采用Li-6400土壤呼吸测定系统(LI-COR,美国)检测土壤呼吸,检测时间为晴朗无风天气的上午9:00-11:00。

1.3 土壤DNA提取及16S rRNA基因高通量测序

土壤DNA采用Fast DNA Spin Kit for Soil(MP Biomedicals,Santa Ana,CA,美国)试剂盒提取。每个样品称取0.50 g鲜土,按照说明书操作提取DNA。

选取细菌16S rRNA基因的V4~V5区进行高通量测序测定。PCR扩增采用特异性引物515F(5′-GTGCCAGCMGCCGCGGTAA-3′)/907R(5′-CC GTCAATTCMTTTRAGTTT-3′)。PCR扩增条件包括94℃ 5 min,90℃ 60 s,55℃ 60 s,72℃ 75 s,30个循环,之后72℃ 10 min。反应产物采用QIA quick PCR Purification kit(Qiagen)进行纯化。将不同样品的PCR扩增产物等摩尔混合后,采用Illumina公司MiSeq测序仪完成序列分析(委托上海派森诺生物科技股份有限公司测定)。

1.4 数据统计分析

高通量测序所得序列按照以下步骤进行分析[14]:(1)双端序列采用FLASH进行拼接;(2)使用Cutadapt软件切除引物;(3)采用QIIME(1.91)去除质量分数低于20、序列短于300 bp的低质量序列;(4)采用RDP数据库去除嵌合体;(5)得到的高质量序列采用Uparse软件,以97%相似度进行操作分类单元(Operation taxonomic unit,OTU)划分,采用Blast方法以Greengeens13.8数据库为比对进行注释。将未注释到门水平及注释为古菌的序列删除后,所有样品随机抽取11 000条序列进行后续分析。细菌香农指数(Shannon)和ACE指数在QIIME中计算。采用STAMP 2.1.3软件Welch’s-test进行属水平上的差异物种分析。采用FAPROTAX 数据库进行细菌功能预测。

使用SPSS 22.0软件中皮尔森(Pearson)双尾检验进行细菌功能与土壤性质相关性分析;平均值多重比较采用邓肯新复检验法(Duncan’s New Multiple Range Test)进行显著性检验(< 0.05)。采用单因素方差分析对不同处理全生育期内土壤呼吸速率平均值进行差异显著性检验。采用Microsoft Excel 2007和Origin 8.0软件进行数据处理和绘图。

2 结 果

2.1 不同物料处理下玉米籽粒产量和地上部生物量

图1a)表示玉米籽粒产量在四个处理间无显著差异,变动范围为8 840~9 742 kg·hm–2;从地上部生物量角度来看,CK、R、RMT处理间生物量类似,但MT处理的生物量较CK显著降低,降低了10%(图1b))。

注:CK、R、MT和RMT分别表示不添加有机物料、施用秸秆、施用木本泥炭、秸秆和木本泥炭联合施用;误差线表示标准差;不同字母表示处理间的显著差异(邓肯法,P<0.05)。下同Note:CK,R,MT,RMT stands for treatment of no organic material,straw,wood peat and straw coupled with wood peat,respectively; The error bars represent the standard deviation of the mean,different letters indicate significant differences between treatments(Duncan method,P<0.05). The same below

2.2 不同物料处理下土壤有机质和有效养分

由表1可见,与CK处理相比,玉米收获后R处理土壤有机质(SOM)无显著变化,而MT和RMT处理的SOM含量分别较CK增加79%和56%。土壤全氮在处理间无显著性差异,从而导致土壤碳氮比在不同处理间的变化趋势与SOM的变化趋势类似。有效磷含量为MT处理最高,较其他处理高39%~82%;硝态氮含量为MT与RMT处理间无显著差异,并较其他两个处理高44%~58%。

表1 不同处理下土壤理化性质

2.3 不同物料处理下玉米生育期土壤呼吸动态变化

图2表示,在玉米生育期,施用秸秆的RMT和R处理土壤呼吸速率在整个玉米生育期通常较不施用秸秆的MT和CK处理高。对全生育期的土壤呼吸速率平均值进行方差分析的结果表示,RMT和R处理分别较CK处理高64%和40%,而MT处理则与CK处理差异未达显著水平。

2.4 不同物料处理下土壤细菌群落组成

经过质量控制,总共得到173 793条高质量序列(每个样品序列数在11 544~20 507之间)。将所有样品序列均一化为11 000条后,以97%相似度与Greengeens数据库进行比对,总共得到841条基本分类单元(OTU)。图3a)表示,土壤细菌丰富度(ACE指数)在各处理间无显著性差异,说明各处理间细菌群落丰富度变化不显著。与CK处理相比,R和MT处理香农指数显著升高,说明细菌群落多样性较高,而RMT处理则对细菌多样性无显著影响(图3b))。

基于均一化后的OTU丰度进行主成分分析,前三轴总共解释了71%的总方差(图4a))。 CK处理与RMT处理距离相对较近,而与R和MT距离较远,处理间呈现一定的群落分异,说明与CK处理相比,R和MT处理对细菌群落组成的影响大于RMT处理,但多元方差分析(Adonis)发现并未达到显著水平。

注:折线图表示整个玉米生育期土壤呼吸速率的动态变化,柱状图表示整个玉米生育期土壤呼吸速率的平均值。Note:The dashed line represents dynamic change in soil respiration rate during the whole maize growth period,and the column mean of soil respiration rates during the whole maize growth period.

图3 不同处理土壤细菌丰富度与多样性

细菌16S rRNA高通量测序序列经物种注释后归属于20个门、66个纲、128个目、195个科和262个属(图4b))。优势菌门为放线菌门(Actinobacteria)、变形菌门(Proteobacteria)和绿弯菌门(Chloroflexi),相对丰度分别为34.07%、27.77%和11.75%。其余相对丰度大于1%的门分别为酸杆菌门(Acidobacteria,11.22%)、芽单胞菌门(Gemmatimonadetes,5.85%)、浮霉菌门(Planctomycetes,5.43%)、拟杆菌门(Bacteroidetes,2.86%)、厚壁菌门(Firmicutes,1.60%)和硝化螺旋菌门(Nitrospirae,1.26%)。单因素方差分析发现,与CK 处理相比,绿弯菌门和芽单胞菌门相对丰度在R处理中升高20.61%和20.05%(<0.05),而浮霉菌门相对丰度在R和MT处理分别降低了13.80%和8.73%(<0.05)。

图4 不同处理土壤细菌主成分分析(a))和门水平下微生物组成(b))

以CK处理为对照,在属水平上对R、MT和RMT处理进行差异物种分析,结果如图5。其中R处理中放线孢菌属()、厌氧粘细菌属()节细菌属()固氮弧菌属()指孢囊菌属()褐螺菌属()和杆状孢囊菌属()等8个属相对丰度显著升高,而壤霉菌属()微杆菌属()硝化杆菌属()和诺卡氏菌属()等四个属相对丰度显著降低;MT处理中土壤杆菌属()节螺藻属()固氮弧菌属()纤维菌属()德沃斯氏菌属()藤黄色单胞菌属()农研丝杆菌属()类诺卡氏菌属()和等9个属相对丰度显著升高,而出芽菌属()和硝化杆菌属()等2个属相对丰度显著降低;RMT处理物种组成与CK相似,仅有节细菌属()和农研丝杆菌属()2个属相对丰度显著升高,微杆菌属()和苍白杆菌属()2个属相对丰度显著降低。

图5 不同处理细菌属水平菌种差异

2.5 不同物料处理下土壤细菌功能预测

使用FAPROTAX 1.1对微生物群落进行功能预测,在一定程度上反映微生物群落功能。经分析,共获得37项功能分组,将该37项预测功能进行单因素方差分析,筛选出在处理间有显著差异的6项功能,包括化能异养(Chemoheterotrophy)、需氧化能异养(Aerobic chemoheterotrophy)、硝化功能(Nitrification)、硝酸盐还原功能(Nitrate reduction)、尿素代谢功能(Ureolysis)和纤维素代谢功能(Cellulolysis)。对上述6种功能中心化后进行聚类分析(图6),发现所有样品可以分为三组。其中,第一组包含R处理3个重复,第二组包含MT处理3个重复,第三组包括CK处理的3个重复和RMT处理的3个重复。与CK相比,R处理中化能异养、需氧化能异养、尿素代谢功能均显著降低;此外,R处理中硝化功能最高,较其他处理高22.06%~41.44%。MT处理中需氧化能异养、尿素代谢功能显著降低,而纤维素代谢功能则显著升高;CK与RMT处理间功能无显著性差异。

2.6 细菌功能与土壤性质之间的关系

注:CH表示化能异养功能、ACH表示需氧化能异养功能、Ni表示硝化功能、NR表示硝酸盐还原功能、Ur表示尿素代谢功能、Cel表示纤维素代谢功能。下同Note:CH stands for chemoheterotrophy,ACH for aerobic chemoheterotrophy,Ni for nitrification,NR for nitrate reduction,Ur for ureolysis,and Cel for cellulolysis. The same below

表2 差异功能与土壤理化指标、细菌多样性及差异门之间的关系

注:Chl表示绿弯菌门、Gem表示芽单胞菌门、 Pla表示浮霉菌门、Y表示玉米产量;ns表示相关关系不显著(>0.05),*和**分别表示显著相关(<0.05)和极显著相关(<0.01)。Note:Chl stands for Chloroflexi,Gem for Gemmatimonadetes,and Pla for Planctomycetes,Y for maize yield;ns indicates no significant correlation,* and ** indicates significant correlation at 0.05 and 0.01 levels,respectively.

3 讨 论

3.1 不同物料添加对作物产量和土壤化学性质的影响

本研究结果表明,MT处理玉米地上部生物量在所有处理中最低(图1),一个可能的解释是木本泥炭富含大分子惰性有机质,微生物很难分解利用,养分难以释放,这与MT处理玉米生育期的土壤呼吸速率处于最低水平相一致(图2)。此外,由于木本泥炭具有较强的吸附能力,导致土壤中养分离子难以被作物吸收利用,从而导致产量降低[15]。同时,R和RMT处理玉米籽粒产量和地上生物量均与CK无显著差异。与前人的研究结果一致,长期秸秆还田可提高作物产量[16],而短期秸秆还田对作物产量无显著影响[17]。上述结果说明,在潮土中单独施用秸秆或秸秆和木本泥炭联合施用可在短期内维持玉米产量不变,甚至有增加的趋势,而单独施用木本泥炭则显著降低玉米产量。

3.2 不同物料添加对细菌丰富度和多样性的影响

不同处理土壤细菌丰富度间无显著性差异。R处理细菌多样性显著高于CK处理,与前人[20]的研究结果一致,这可能是由于秸秆的加入为土壤带来大量易利用有机质,促进土壤中丰富营养型微生物生长,从而导致多样性升高。关于施用木本泥炭对细菌多样性的研究鲜有报道,本研究结果表明,土壤加入微生物难以利用的木本泥炭后,细菌多样性同样显著高于CK处理。一个可能的解释是木本泥炭的加入有利于那些分解大分子有机物的贫瘠营养型微生物生长[20],导致多样性升高。有意思的是,RMT处理中细菌多样性与CK差异未达显著水平。物料的性质会影响微生物群落组成和多样性[18],当微生物易利用的秸秆和难利用的木本泥炭加入后,丰富营养型和贫瘠营养型细菌获取碳源能力和微生物群落功能与CK处理差异不显著(图6),导致细菌多样性维持在相似水平。与本结果类似,有研究[21]表明生物炭添加对土壤微生物多样性无显著影响。

3.3 不同物料添加对微生物群落组成的影响

与前人的研究结果相同,放线菌门、变形菌门和绿弯菌门是该地区潮土的优势细菌[22]。主成分分析的结果表明,RMT处理与CK处理细菌群落组成相似,而R和MT处理与CK处理细菌群落组成差异较大。在门水平上,绿弯菌门和芽单胞菌门相对丰度在R处理中显著升高(图4b))。与本研究结果类似,Yu等[23]采用高通量测序方法发现,经过6 a连续秸秆还田后,土壤中绿弯菌门相对丰度显著高于秸秆移除处理。Wegner和Liesack[24]研究表明,绿弯菌门对还田秸秆半纤维素的降解具有重要作用。Navarro-Noya等[22]研究表明,芽单胞菌门在秸秆还田处理中显著升高,此外,芽单胞菌门可根据代谢需求调节对C和N的摄入量[25],表明其对不同土壤环境的广泛适应性。浮霉菌门相对丰度在R和MT处理中显著降低。研究表明浮霉菌门是一种贫瘠营养型细菌,参与土壤碳氮循环,在土壤有机质分解中具有重要作用,但生长速率慢[26]。R和MT处理中浮霉菌门相对丰度显著降低,可能与两处理中土壤细菌多样性显著提高,从而与生长较慢的浮霉菌门产生较强的竞争作用有关。

在属水平上,与CK处理相比,R处理中和等8个属相对丰度显著升高(图5)。其中和在秸秆分解中具有重要作用,能够分解纤维素、淀粉等[27-28]。而和等四个属相对丰度在R中显著降低。其中和均属于放线菌门,其在土壤有机质转化和溶磷方面具有重要作用[29-30],这与R处理土壤有效磷显著降低结果一致(表1)。MT处理中和等9个属相对丰度显著升高(图5)。其中和等6个属均具有分解纤维素、木质素、多环芳烃等大分子有机物的能力[31-32]。RMT处理与CK处理细菌属相对丰度变化不明显,其中,偏好高浓度碳环境的和相对丰度显著升高,而具有溶磷作用的和[33]相对丰度显著降低,这与RMT处理土壤有机质显著升高和有效磷较低结果一致(表1)。

以上结果说明,易利用的秸秆加入促进了土壤中秸秆降解细菌的生长,但分解土壤有机质的细菌相对丰度则显著降低,这种微生物群落变化也在一定程度上解释了R处理中较高的土壤呼吸速率以及较低的土壤有机质增加量;难利用木本泥炭的加入导致土壤中降解大分子有机物的贫瘠营养型细菌相对丰度显著升高,这与其较低的土壤呼吸速率及较高的土壤有机质增加量结果一致;而秸秆和木本泥炭混合施用则对细菌群落组成影响较小。

3.4 不同物料添加对微生物功能的影响

4 结 论

由于木本泥炭和秸秆两种有机物料本身性质的差异,造成了秸秆施用能够显著提高土壤呼吸,R和RMT处理在玉米整个生育期的平均呼吸速率分别提高40%和64%;而木本泥炭施用能够快速提高土壤有机质,MT和RMT处理土壤有机质分别升高79%和56%,但MT处理地上生物量降低10%。此外,在微生物群落结构和功能方面,主要表现为施用秸秆的R处理提高了土壤中降解秸秆的菌群,降低尿素代谢功能,而施用木本泥炭的MT处理提高了土壤中降解大分子有机物的菌群和尿素代谢功能,而二者配合施用对微生物群落和功能的影响不大。综合而言,在潮土区秸秆和木本泥炭施用对作物产量、土壤养分、微生物群落结构和功能影响不同,但二者配合施用有利于土壤肥力提升、维持稳定的微生物群落结构和功能,同时消除了单独施用木本泥炭产量降低的消极影响。

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Effect of Application of Straw and Wood Peat for a Short Period on Soil Organic Matter and Microbial Community in Composition and Function in Fluvo-aquic Soil

ZHAO Wenhui1, 2, MA Lei1, 2, XU Jisheng1, TAN Jun3, ZHANG Jiabao1, ZHAO Bingzi1†

(1. State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; 2. University of Chinese Academy of Sciences, Beijing 100049, China; 3. View Sino International Limited Company, Beijing 100004, China)

Fluvo-aquic soil is widely distributed in the North China Plain. The soil is very low in organic matter, which is hard accumulate therein. Maybe, this is the main cause preventing high crop yields. Application of extraneous organic materials (i.e. straw and woody peat) is a common agricultural strategy to improve soil organic matter (SOM) content in this agricultural region. However, so far only limited information is available in the literature about effects of applying crop straw and/or wood peat on crop yield and soil fertility, and it is not clear whether it is superior to direct straw returning to the field.In this study, a field experiment, designed to have four treatments, that is, CK(Do not apply any organic material, only chemical fertilizer), R (Chemical fertilizer and 7 500 kg·hm–2of straw), MT (Chemical fertilizer and 7 005 kg·hm–2of the wood peat), and RMT (Chemical fertilizer, 7 500 kg·hm–2of straw and 7 005 kg·hm–2of the wood peat) was conducted in a field of Fluvo-aquic soil in Fengqiu, Henan. Crop yield and soil fertility indices, such as SOM, total nitrogen (TN), available phosphorus (AP), nitrate (NO3-N) and carbon nitrogen ratio (C: N) of the soil were measured. High-throughput sequencing was employed to characterize diversity and composition of the bacterial community in the soil, FAPROTAX database was used in prediction of bacterial functions.Results show that there was no significant difference between Treatments R and RMT and CK in aboveground biomass, but Treatment R and RMT was 40% and 64% respectively, higher than CK in average respiration rate in the whole growth period of maize. However, Treatment MT was 10% lower than CK in aboveground biomass, and did not differ much in average respiratory rate. On the other hand, the treatments varied in effect on soil fertility. Compared with CK, Treatment R was 23.56% lower in AP, while Treatment MT was 79.30%, 39.12%, 43.63% and 86.50% higher, respectively, in SOM, AP, NO3-N and C: N. Through high-throughput sequencing and function prediction, it was found that the bacterial communities in Treatments R and MT differed significantly from that in CK in composition and function, while that in Treatment RMT was similar to that in CK, and the soil bacterial communities in Treatments R and MT were significantly higher than that in CK in diversity. Compared with CK, the relative abundances of Chloroflexi, Gemmatimonadetes,,andthat could decompose and utilize fresh straws were significantly increased in Treatment R, but the functions of Chemoheterotrophy, Aerobic chemoheterotrophy and Ureolysis were decreased, while in Treatment MT, the relative abundances of,,,,andthat could degrade macromolecular organics were significantly increased and the function of Cellulolysis was strengthened and that of Aerobic chemoheterotrophy was weakened. In addition, the predicted functions of the soil microbial communities in Treatments R and MT were significantly different from those in CK, but thoese in Treatment RMT were similar to those in CK. In addition, the predicted functions of the soil microbacterial communities in Treatments R and MT were significantly different from those in CK, while those in Treatment RMT were similar to those in CK.In conclusion, in the Fluvo-aquic soil area, although applying woody peat alone can rapidly increase SOM, it may lead to decrease in crop yield temporarily or in a short term, which may be relative to changes in the soil microbial community in composition and function, thus affecting nutrient recycling and transformation. Combined application of straw and woody peat is beneficial to building up of soil fertility, and maintaining the soil microbial community in structure and function.

Straw returning; Woody peat; High-throughput sequencing; Microbial community; Function prediction

S154.36

A

10.11766/trxb201811300537

赵文慧,马垒,徐基胜,谭钧,张佳宝,赵炳梓. 秸秆与木本泥炭短期施用对潮土有机质及微生物群落组成和功能的影响[J]. 土壤学报,2020,57(1);153–164.

ZHAO Wenhui,MA Lei,XU Jisheng,TAN Jun,ZHANG Jiabao,ZHAO Bingzi. Effect of Application of Straw and Wood Peat for a Short Period on Soil Organic Matter and Microbial Community in Composition and Function in Fluvo-aquic Soil [J]. Acta Pedologica Sinica,2020,57(1);153–164.

* 国家重点研发计划项目(2016YFD0300802)和现代农业产业技术体系建设专项资金(CARS-03)共同资助Supported by the National Key Research and Development Program of China(No. 2016YFD0300802)and the Earmarked Fund for China Agriculture Research System(No. CARS-03)

,E-mail:bzhao@issas.ac.cn

赵文慧(1993—),女,安徽亳州人,硕士研究生,主要从事土壤微生物研究。E-mail:whzhao@issas.ac.cn

2018–11–30;

2019–02–15;

2019–03–15

(责任编辑:陈荣府)

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