秸秆还田与施肥方式对稻麦轮作土壤细菌和真菌群落结构与多样性的影响*

张翰林, 白娜玲, 郑宪清, 李双喜, 张娟琴, 张海韵, 周 胜, 孙会峰, 吕卫光**

秸秆还田与施肥方式对稻麦轮作土壤细菌和真菌群落结构与多样性的影响*

张翰林1,2, 白娜玲1,2, 郑宪清1,2, 李双喜1,2, 张娟琴1,2, 张海韵1,2, 周 胜1,3, 孙会峰1,3, 吕卫光1,2**

(1. 上海市农业科学院生态环境保护研究所/上海市设施园艺技术重点实验室/上海市农业环境保护监测站 上海 201403; 2. 农业部上海农业环境与耕地保育科学观测实验站 上海 201403; 3. 上海低碳农业工程技术研究中心 上海 201403)

为探索秸秆还田与施肥方式2种农田措施对水稻-小麦(稻麦)轮作土壤微生物群落的影响, 阐释其对土壤细菌和真菌群落结构和多样性的影响机制, 本研究通过7年稻麦轮作长期定位监测试验, 设置无肥空白(CK)、常规施肥(RT)、秸秆还田+常规施肥(RS)和秸秆还田+缓释肥(SS) 4个处理, 采用Illumina Miseq高通量测序技术, 分析土壤细菌和真菌群落结构和多样性, 探索影响微生物群落的主控环境因子。结果表明, SS作物产量在2016年和2017年分别比RT显著提高11.6%和8.2% (水稻)、4.8%和3.6% (小麦), 与RS无显著差异。相比RT, 秸秆还田处理显著降低了土壤pH, 提升了土壤有机碳和铵态氮含量; 与RS相比, SS处理提高了铵态氮含量。秸秆还田处理提升了真菌群落多样性, 但对细菌群落多样性无显著影响。SS与RS在细菌真菌群落多样性方面均无显著差异。相关性分析表明, 细菌群落多样性与土壤pH呈负相关, 与总氮含量呈正相关; 真菌群落多样性则与土壤有机碳含量显著正相关。NMDS分析表明, 施肥对于细菌群落结构影响较大(55.61%), 真菌群落结构则对秸秆还田响应更明显(26.94%)。与RT相比, 秸秆还田显著提升了细菌放线菌门、绿弯菌门、厚壁菌门的相对丰度, 同时显著提升了真菌中子囊菌门的相对丰度, 降低了担子菌门和接合菌门的相对丰度, 加强了土壤碳氮循环能力并抑制了病原菌。SS与RS相比, 仅提升了真菌中子囊菌门的相对丰度。综上, 秸秆还田配施缓释肥有助于维持或者提高土壤养分有效性、作物产量及细菌真菌群落多样性, 可以促进土壤碳氮循环。

土壤微生物; 群落结构; 土壤养分; 秸秆还田; 缓释肥; 高通量测序

土壤微生物在陆地生态系统中具有重要作用, 负责调节土壤养分的生物地球化学循环, 促进植物生长, 维持生态系统的稳定性[1]。细菌作为土壤中最丰富的微生物种之一, 在多种土壤生态过程中均起到重要的功能性作用, 如分解有机质和促进土壤养分矿化等[2]。真菌则是重要的分解者, 可以分解土壤中植物残体和纤维素、半纤维素、木质素等难降解有机物, 在降解过程中释放养分, 促进植物生长[3]。由于土壤中细菌、真菌群落对环境因素变化十分敏感, 土壤细菌和真菌群落多样性常常被认为是揭示土壤质量状况的重要指标。一般来说, 较高的细菌和真菌多样性表示土壤生态系统更加稳定和健康[4-5]。

农作物秸秆是数量最大的农业可再生资源。随着我国生态农业的大力提倡, 农作物秸秆还田已成为农业资源循环利用的重要方式[6]。秸秆还田可以通过改变土壤理化性状, 直接或间接地影响土壤微生物群落。郭梨锦等[7]发现短期(2年)水稻(L.)、小麦(L.)秸秆还田显著提升了土壤细菌和真菌的生物量和多样性指数; 而Sun等[8]认为麦秸秆还田对土壤细菌群落的影响不大, 且细菌群落受pH影响较大; Chen等[9]采用磷脂脂肪酸(PLFA)的研究发现, 我国中东部3个水稻-小麦轮作地区中, 只有1个地点的秸秆还田显著增加了细菌多样性, 其余地点变化不显著; 萨如拉等[10]在砂壤土和中壤土的玉米(L.)田开展秸秆配施秸秆腐熟剂研究, 发现不同秸秆腐熟剂与土壤质地对真菌群落的影响并不相同。上述研究表明土壤细菌和真菌群落对秸秆还田的响应受土壤质地、理化性质、地理位置等多种因素影响, 因此加强秸秆还田在不同农业管理方式下对土壤微生物群落多样性影响的认识十分必要。

缓/控释肥料施用技术作为近年来农业部的一项主推技术, 可以有效降低施肥次数和减轻养分流失, 从而提高氮素利用率[11], 在华东地区已经逐步进行推广。Pan等[12]发现与常规化肥相比, 单独施用缓释肥并没有显著改变土壤细菌数量与多样性。而孙会峰等[13]的研究表明, 与秸秆还田+常规化肥对比, 秸秆还田配施缓释肥提高了水稻产量, 提升了氮素利用率, 具有良好的应用前景。但目前秸秆还田配施缓释肥对土壤微生物群落的影响还鲜有研究。本研究采用长期定位试验方式, 应用Illumina高通量测序技术, 考察比较水稻-小麦轮作秸秆还田配施常规施肥和缓释肥对土壤细菌和真菌群落结构和多样性的影响, 识别特殊细菌和真菌种类, 阐明影响微生物群落结构的主控环境因子, 以期为华东地区农田秸秆还田与施肥技术优化提供科学依据。

1 材料与方法

1.1 试验区概况

试验在上海低碳农业工程技术研究中心定位试验基地进行, 位于上海市奉贤区庄行镇(30°53′N, 121°23′E), 年平均气温15.7 ℃, 年降水量1162.0 mm, 全年无霜期225 d。土壤类型为砂壤土, 常年采用水稻-小麦两熟轮作制度。试验开始时部分土壤理化性质如下: pH 8.41, 有机碳(SOC) 8.71 g∙kg−1, 总氮(TN) 0.94 g∙kg−1, 总磷(TP) 0.98 g∙kg−1。

1.2 试验设计

试验自2011年水稻季开始至2017年水稻季结束。水稻试验品种为‘花优14’, 每年6月中旬进行人工插秧, 栽插行株距20 cm´25 cm, 11月上旬收获。小麦试验品种为‘扬麦12号’, 每年12月上旬播种, 行距16 cm, 5月下旬收获。设置常规施肥(RT)、秸秆还田+常规施肥(RS)、秸秆还田+缓释肥(SS)和不施肥对照(CK)共4个处理。每个处理设置3个重复, 所有重复均采用随机区组设计。每个长方形小区面积为60 m2, 四周用水泥垄和防渗膜隔开。试验所用肥料为普通尿素、树脂和硫磺双包膜尿素、过磷酸钙和硫酸钾。根据上海地区水稻和小麦的平均施肥量, 3个施肥处理均施用相同的纯量氮、磷、钾(水稻季分别为225 kg∙hm−2、112.5 kg∙hm−2和255 kg∙hm−2, 小麦季分别为180 kg∙hm−2、90 kg∙hm−2和204 kg∙hm−2)。RT和RS中氮肥按基肥、蘖肥、穗肥比例5∶3∶2施用, SS氮肥则作基肥一次性施入。在RS和SS中, 稻麦两季均在作物收获后, 将秸秆深翻还田, 翻耕深度约为10~15 cm, 还田量为秸秆产生量的1/2。秸秆的养分含量测定后计入总施肥量, 稻秸秆和麦秸秆的平均氮、磷、钾含量分别为3.3 g∙kg-1、1.9 g∙kg-1、13.5 g∙kg-1和3.8 g∙kg-1、2.4 g∙kg-1、18.4 g∙kg-1。

在试验的最后一季水稻收获期(2017年11月5日)采集土壤样本。每个小区采用S型取样法随机采集5个土样(0~20 cm)并混合成1个样本。土样储存在低温保鲜袋中, 立即带回实验室。一部分样品风干后进行土壤理化性质测定, 另一部分则保存在-20 ℃下进行DNA提取和高通量测序分析。

1.3 测定项目与方法

高通量测序分析: 取0.5 g土样, 采用MoBio PowerSoil®DNA提取试剂盒(12888)提取土壤DNA。将纯化后的基因组DNA作为聚合酶链反应(PCR)的模板。细菌V3-V4区扩增引物采用515F (5′-GTGCCAGCMGCCGCGG-3′)/907R(5′-CCGTCAATTCMTTTRAGTTT-3′)[15], 真菌ITS1区段扩增引物采用ITS5(5′-GGAAGTAAAAGTCGTAACAAG G-3′)/ITS4(5′-TCCTCCGCTTATTGATATGC-3′)[16]。PCR采用25 µL反应体系: 10倍PCR buffer 5 µL (with MgCl2), dNTP 0.5 µL, 正向反向引物各0.5 µL, Tap酶0.25 µL (250 U), DNA模板1 µL, ddH2O补齐至25 µL。PCR反应策略: 98 ℃预变性3 min, 98 ℃15 s, 50 ℃30 s和72 ℃ 30 s, 分别进行25个(细菌)和35个(真菌)循环, 最后在72 ℃下延伸7 min。PCR产物用1.7%琼脂糖凝胶电泳检测后, 送至上海派森诺生物科技有限公司, 在Illumina MiSeq测序平台上进行高通量测序分析。获得原始序列后进行质量控制, 之后在97%序列相似性水平上聚类成可操作的分类单元(Operational Taxonomic Units, OTUs)。对照RDP和UNITE数据库进行分类注释, 获取对应的细菌和真菌分类学信息。

1.4 统计分析

采用Tukey’s-HSD单因素方差分析(ANOVA)对各处理间的理化指标差异显著性进行分析(SPSS 19.0)。细菌和真菌的丰富度和多样性采用Chao1和Shannon指数表征(Mothur, v 1.30.1)。采用非度量多维尺度分析(non-metric multidimensional scaling, NMDS)确定细菌和真菌的群落结构差异(R语言, v 3.0.2)。通过Galaxy在线分析平台(http://huttenhower.sph.harvard. edu/galaxy/), 应用LEfSe分析揭示导致细菌和真菌群落显著差异的物种。采用Pearson相关性分析法研究细菌和真菌多样性与环境因子之间的关联度。

2 结果与分析

2.1 秸秆还田与施肥方式对水稻-小麦轮作体系产量和土壤理化性质的影响

不同试验处理显著影响了水稻和小麦产量(图1)。SS的水稻产量在2016年和2017年分别为8.0 t∙hm−2、9.3 t∙hm−2, 小麦产量分别为5.4 t∙hm−2、5.8 t∙hm−2, 均显著高于RT, 分别高出11.6%和8.2% (水稻)、4.8%和3.6% (小麦); 与RS相比, 3年内稻麦产量均无显著差异。与RT相比, RS仅在2016年稻、麦产量显著升高, 分别高出9.3%和4.8%, 其余均无显著差异。

CK: 不施肥空白; RT: 常规施肥; RS: 秸秆还田+常规施肥; SS: 秸秆还田+缓释肥。不同小写字母表示同一年份不同处理间差异显著(0.05)。CK: no fertilizer; RT: conventional fertilization; RS: straw returning + conventional fertilization; SS: straw returning + slow-release fertilization. Different lowercase letters indicate significant differences among treatments in the same year at0.05.

表1 秸秆还田与施肥方式对水稻-小麦轮作土壤理化性质的影响

CK: 不施肥空白; RT: 常规施肥; RS: 秸秆还田+常规施肥; SS: 秸秆还田+缓释肥。表中数据为3个数值的平均值±标准误; 同列数据后不同字母表示处理间差异显著(<0.05)。CK: no fertilizer; RT: conventional fertilization; RS: straw returning + conventional fertilization; SS: straw returning + slow-release fertilization. Date in the table are mean±SE. Values followed by different letters in a column are significantly different (<0.05).

2.2 秸秆还田与施肥方式对土壤细菌和真菌群落多样性的影响

各施肥处理的土壤细菌群落丰富度和多样性分别采用Chao1和Shannon指数表征, 结果显示其受施肥影响显著(表2)。3个施肥处理的细菌群落Chao1和Shannon范围分别为2760~2795和9.74~9.77, 均显著高于CK, 且彼此之间无显著差异; 各施肥处理土壤真菌群落多样性则是受秸秆还田影响显著, 2个秸秆还田处理的真菌群落Chao1和Shannon范围分别为630~631和6.48~6.51, 均显著高于RT和CK, 但SS和RS之间无显著差异, RT的真菌群落多样性指数最低, 但与CK之间无显著差异。

表2 秸秆还田与施肥方式对水稻-小麦轮作土壤细菌和真菌群落多样性指数(Chao1和Shannon)的影响

CK: 不施肥空白; RT: 常规施肥; RS: 秸秆还田+常规施肥; SS: 秸秆还田+缓释肥。表中数据为3个数值的平均值±标准误; 同列数据后不同字母表示处理间差异显著(<0.05)。CK: no fertilizer; RT: conventional fertilization; RS: straw returning + conventional fertilization; SS: straw returning + slow-release fertilization. Date in the table are mean ± SE. Values followed by different letters in a column are significantly different (<0.05).

2.3 秸秆还田与施肥方式对土壤细菌和真菌群落组成的影响

土壤细菌群落在门水平上的组成如图2a所示。水稻-小麦轮作土壤优势细菌门(相对丰度>10%)有变形菌门(Proteobacteria, 29.2%~33.9%)、绿弯菌门(Chloroflexi, 21.0%~27.2%)、放线菌门(Actinobacteria, 12.2%~16.4%)和酸杆菌门(Acidobacteria, 9.7%~12.5%), 其余相对丰度高于1%的细菌门还有拟杆菌门(Bacteroidetes, 2.5%~4.3%)、芽单胞菌门(Gemmatimonadetes, 3.0%~ 3.5%)、硝化螺旋菌门(Nitrospirae, 3.1%~3.3%)和厚壁菌门(Firmicutes, 1.9%~3.3%)。与RT相比, 2个秸秆还田处理(SS和RS)均提升了放线菌门、绿弯菌门和厚壁菌门的相对丰度, 分别平均提高30.2%、13.0%和63.5%。SS和RS之间各细菌门相对丰度均无显著差异。

土壤真菌群落在门水平上的组成(相对丰度>1%)如图2b所示。水稻-小麦轮作土壤主要有子囊菌门(Ascomycota, 51.0%~69.8%)、担子菌门(Basidiomycota, 11.9%~24.7%)、接合菌门(Zygomycota, 1.6%~12.7%)和球囊菌门(Glomeromycota, 5.0%~5.8%)。与RT相比, 2个秸秆还田处理(SS和RS)显著提升了子囊菌门的相对丰度, 平均提高32.3%, 并且降低了担子菌门和接合菌门的相对丰度, 分别平均减少46.8%和36.9%。与RS相比, SS仅在子囊菌门有提高, 其他真菌门相对丰度均无显著差异。

CK: 不施肥空白; RT: 常规施肥; RS: 秸秆还田+常规施肥; SS: 秸秆还田+缓释肥。CK: no fertilizer; RT: conventional fertilization; RS: straw returning + conventional fertilization; SS: straw returning + slow-release fertilization.

LEfSe分析结果显示, 不同处理细菌群落(图3a)有5个存在显著差异的类群(LDA值>3)。其中与SS相关1项, 为植物栖居菌属(, 放线菌门); 与RT相关2项, 草杆菌科(Oxalobacteraceae, 变形菌门)和马赛菌属(, 变形菌门); 与CK相关2项, β-变形菌纲(Betaproteobacteria, 变形菌门)和亚硝化单胞菌目(Nitrosomonadales, 变形菌门)。真菌群落(图3b)中有7个存在显著差异的类群(LDA值>3)。其中与SS相关1项, 多孢囊霉目(Diversisporales, 球囊菌门); 与RS相关2项, 珊瑚菌属(, 担子菌门)和牛肝菌目(Boletales, 担子菌门); 与RT相关3项, 蛙粪霉目(Basidiobolales, 接合菌门)、蛙粪霉科(Basidiobolaceae, 接合菌门)和蛙粪霉属(, 接合菌门); 与CK相关1项, 弯孢霉属(, 子囊菌门)。

CK: 不施肥空白; RT: 常规施肥; RS: 秸秆还田+常规施肥; SS: 秸秆还田+缓释肥。CK: no fertilizer; RT: conventional fertilization; RS: straw returning + conventional fertilization; SS: straw returning + slow-release fertilization.

2.4 秸秆还田与施肥方式对土壤细菌和真菌群落结构的影响

通过NMDS分析可以发现, CK延X轴方向与其他3种施肥处理明确分离(图4a), 不施肥土壤细菌群落结构与其他3种施肥处理差异显著, 解释度为55.61%, 而3个施肥处理细菌群落结构之间则分离不明显, 说明施肥与否对细菌群落结构变化影响显著; 4个处理的真菌群落结构相比细菌群落结构分离趋势更加明显(图4b), 延X轴CK、RT与RS、SS明显分离, 解释度为26.94%, 说明真菌群落结构对于秸秆还田措施的相应更加显著, 而RS和SS之间的真菌群落结构差异不明显。

CK: 不施肥空白; RT: 常规施肥; RS: 秸秆还田+常规施肥; SS: 秸秆还田+缓释肥。CK: no fertilizer; RT: conventional fertilization; RS: straw returning + conventional fertilization; SS: straw returning + slow-release fertilization.

2.5 土壤细菌和真菌群落多样性与环境因子间的关联性

土壤细菌和真菌丰富度及多样性指数(Shannon和Chao1)与土壤性质的相关分析结果如表3所示。pH影响细菌群落多样性最显著, 与细菌多样性呈显著负相关(<0.01), 本研究中pH均高于8, 说明趋近中性的pH更有利于细菌群落的多样性; 同时细菌群落多样性还与TN呈显著正相关(<0.05), 氮素养分供应更易改变细菌群落多样性; 真菌群落多样性则仅与SOC呈显著正相关(<0.05), 与其他指标均无显著相关, 说明有机物的输入对于真菌群落多样性影响显著。

表3 水稻-小麦轮作土壤细菌和真菌多样性指数(Shannon和Chao1)与理化性质间的相关性分析

**和*分别表示<0.01和<0.05水平显著相关。** and * mean significant correlation at<0.01and<0.05 levels, respectively.

3 讨论与结论

本研究发现, 秸秆还田处理并未显著提升土壤细菌群落多样性, 与前人研究结果相似[8,21], 但同时也有一些研究认为秸秆还田可以显著提升细菌群落多样性。这可能与秸秆还田的年限因素有关, 如郭梨锦等[7]和周阳等[22]的研究均为短期秸秆还田(2年和1年), 对土壤细菌群落的促生作用明显, 而在秸秆还田年限超过3年时(本研究秸秆还田年限为7年)[8,21], 对于细菌群落多样性的影响则趋于不显著, 除此之外细菌群落也可能受土壤类型、气候条件和种植作物等多因素的综合影响。本研究中秸秆还田处理的真菌群落多样性均有显著提高, 一方面可能是由于纤维素、木质素等有机物随秸秆输入土壤, 刺激了真菌的生长[3]; 另一方面秸秆还田促进了土壤团聚体的形成, 为真菌的生长创造了良好的条件[23]。秸秆还田条件下, 配施常规化肥和缓释肥并没有对细菌和真菌群落多样性产生显著影响, 说明配施缓释肥与常规化肥一样可以维持土壤微生物群落多样性稳定。

土壤细菌和真菌群落多样性与土壤性质息息相关。本研究发现细菌群落多样性与pH呈显著负相关, 与TN呈正相关, 这与前人研究结果相似[8,21]。pH被认为是微生物群落的指示性指标, 越趋近于中性越有利于细菌群落多样性[24]。土壤TN含量与施肥直接相关, 施肥可以直接提供大量氮素养分供给细菌群落的生长, 促进其多样性的增加[5]。本研究中, 真菌群落多样性与SOC呈正相关, 与何敏红等[25]的研究结果一致, 原因可能是真菌更易并可以更有效地利用有机质, 有机质的输入有利于真菌群落生长。

本研究结果显示, 与常规施肥处理相比, 秸秆还田显著提升了放线菌门、绿弯菌门和厚壁菌门的相对丰度。前人研究发现, 放线菌门在秸秆降解中起重要作用, 可以产生有效降解有机碳的活性酶, 加速秸秆等有机物的降解, 其丰度与微生物的作物秸秆分解能力呈正比[26-27]。绿弯菌门是一种广泛报道的异养寡养菌和兼性厌氧菌, 具有将大分子有机物降解至小分子有机物的能力, 对土壤pH十分敏感, 在中性pH下生长旺盛[28]。厚壁菌门同样在有机物分解中有重要意义, 可以促进纤维素的降解, 是一种碳循环促进菌[26,29]。上述分析表明, 秸秆还田通过有机物输入和改善土壤pH, 可以加速有机物分解和养分释放, 有效加强稻麦轮作土壤碳循环。在秸秆还田条件下缓释肥和常规施肥对于细菌群落影响不明显, 这与Wu等[20]的研究结果相似, 与常规施肥相比, 芹菜施用缓释肥并没有显著改变土壤微生物群落结构。

本研究中, 秸秆还田显著提升了真菌群落中子囊菌门的相对丰度, 降低了担子菌门和接合菌门的相对丰度。中子囊菌门是真菌群落中最丰富和最主要的门, 是土壤有机质(腐殖质、秸秆、枝条等)的主要分解者, 具有分解木质纤维素的重要能力, 在不同类型的农业土壤中广泛存在[30-31]。秸秆还田条件下, 配施缓释肥比常规施肥更能提高中子囊菌门的相对丰度, 其相对丰度增长有助于土壤碳氮循环能力的提升。担子菌门同样具有分解有木质纤维素的能力, 但属于寡养微生物, 适应相对贫瘠的营养环境[32], 其丰度与C/N呈反比[33], 担子菌门相对丰度的降低也说明了秸秆还田增加了土壤碳含量, 提高了C/N, 同时改善了土壤的营养状态, 增加了土壤养分的有效性。接合菌门主要包括寄生虫、小动物病原体和一些真菌[34], 秸秆还田能够降低接合菌门相对丰度说明其具有控制部分病原菌的能力。同时根据LEfSe分析结果, 常规施肥处理中蛙粪霉属显著高于其他处理, 该属是已知的人类病原菌[35]。这说明长期常规施肥会使稻麦轮作系统土壤病原菌数量提升, 而秸秆还田可以有效降低病原菌数量。

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Effects of straw returning and fertilization on soil bacterial and fungal community structures and diversities in rice-wheat rotation soil*

ZHANG Hanlin1,2, BAI Naling1,2, ZHENG Xianqing1,2, LI Shuangxi1,2, ZHANG Juanqin1,2, ZHANG Haiyun1,2, ZHOU Sheng1,3, SUN Huifeng1,3, LYU Weiguang1,2**

(1. Eco-environmental Protection Institute of Shanghai Academy of Agricultural Sciences / Shanghai Key Laboratory of Horticultural Technology / Environmental Protection Monitoring Station of Shanghai City, Shanghai 201403, China; 2. Agricultural Environment and Farmland Conservation Experiment Station of Ministry Agriculture, Shanghai 201403, China; 3. Shanghai Low Carbon Agriculture Engineering Technology Research Center, Shanghai 201403, China)

Straw returning and slow-release fertilizers are widely used in agriculture to reduce non-point source pollution and improve nitrogen use efficiency. However, there are few studies on the effect of straw return combined with slow-release fertilizers on the soil microbial community. This study determined how straw returning combined with fertilization affected the bacterial and fungal communities in rice-wheat rotation soil and the underlying mechanisms. Based on a seven-year rice-wheat rotation system monitoring experiment, four treatments were selected: no fertilizer (CK), regular chemical fertilization (RT), straw returning combined with chemical fertilization (RS), and straw returning combined with slow-release fertilizer (SS). The Illumina MiSeqplatform was used to evaluate the community structure and diversity of soil bacteria and fungi and to detect the primary environmental factors affecting the microbial community. The results showed that the SS rice and wheat yields in 2016 and 2017 were significantly higher than the RT yields (by 11.6% and 8.2% in rice, and 4.8% and 3.6% in wheat, respectively); there was no difference between SS and RS yields. Compared to RT, straw returning significantly decreased soil pH and increased soil organic carbon (SOC) and ammonium nitrogen (NH4+-N) contents; SS had more NH4+-N than RS. The fungal community diversity was higher with straw returning than with RT, but there was no difference in the bacterial community diversity among fertilization treatments; the bacterial and fungal community diversities were the same between RS and SS. Correlation analysis showed that the bacterial community diversity was negatively correlated with pH and positively correlated with soil total nitrogen content, while the fungal community diversity was positively correlated with SOC. Non-metric multidimensional scaling analysis showed that fertilization had a greater effect on the bacterial community structure (55.61%), and straw returning had a greater effect on the fungal community structure (26.94%). Proteobacteria, Chloroflexi, and Acidobacteria (in successive order) were the dominant phyla across all treatments, accounting for 66.07%–71.76% of the total bacterial sequence data. Ascomycota, Basidiomycota, and Zygomycota (in successive order) were the dominant phyla across all treatments, accounting for 88.05%–89.04% of the total fungal sequence data. Compared with RT, the treatments with straw returning significantly increased the relative abundance of Actinobacteria, Chloroflexi, and Firmicutesin the bacterial community, and significantly increased the relative abundance of Ascomycota and decreased the relative abundance of Basidiomycota and Zygomycotain thefungal community. Ecological function analysis of these bacterial and fungal communities showed that straw returning may enhance soil carbon and nitrogen cycling and inhibit pathogens. Compared with RS, SS only increased the relative abundance of Ascomycota in the fungal community; there were no other differences between the relative abundances of bacteria and fungi in RS and SS at the phylum level. Straw returning with slow-release fertilizers can help maintain or improve soil nutrient availability, crop yield, and the diversity of bacterial and fungal communities and can promote soil carbon and nitrogen cycling.

Soil microorganism; Community structure; Soil nutrient; Straw returning; Slow release fertilizer; High throughput sequencing

10.13930/j.cnki.cjea.200502

张翰林, 白娜玲, 郑宪清, 李双喜, 张娟琴, 张海韵, 周胜, 孙会峰, 吕卫光. 秸秆还田与施肥方式对稻麦轮作土壤细菌和真菌群落结构与多样性的影响[J]. 中国生态农业学报(中英文), 2021, 29(3): 531-539

ZHANG H L, BAI N L, ZHENG X Q, LI S X, ZHANG J Q, ZHANG H Y, ZHOU S, SUN H F, LYU W G. Effects of straw returning and fertilization on soil bacterial and fungal community structures and diversities in rice-wheat rotation soil[J]. Chinese Journal of Eco-Agriculture, 2021, 29(3): 531-539

S154.3

* 国家重点研发计划项目(2016YFD0200804)、上海市科技兴农推广项目[沪农科推字(2018)第4-14号]和上海市农业科学院卓越团队建设计划项目[农科创2017(A-03)]资助

吕卫光, 主要研究方向为农田生态。E-mail: lvweiguang@saas.sh.cn

张翰林, 主要研究方向为农田微生物驱动碳氮循环。E-mail: zhanghanlinchick@163.com

2020-06-26

2020-11-23

* This study was supported by the National Key Research and Development Program of China (2016YFD0200804), Shanghai Agriculture Applied Technology Development Program, China (T20180414) and the Outstanding Team Program of Shanghai Academy of Agricultural Sciences [Nongke Chuang 2017(A-03)].

, E-mail: lvweiguang@saas.sh.cn

Jun. 26, 2020;

Nov. 23, 2020