雅鲁藏布江下游沿岸湿地建群种植物根际土壤细菌群落结构和多样性特征

了解雅鲁藏布江大峡谷沿岸不同植被根际土壤细菌群落结构和多样性特征对于揭示该区植被与土壤的相互作用具有重要科学意义。采用Illumina Miseq高通量测序技术,研究了雅鲁藏布江沿岸自然分布和生长的艾草Artemisia argyi H. Lév.&Vaniot、白刺花Sophora davidii(Franch)、八宝Hylotelephium erythrostictum(Miq.)H. Ohba、黄刺玫Rosa xanthina Lindl4种典型植被根际土壤细菌群落结构和多样性,并结合植物根际土壤养分含量进行相关性分析。雅鲁藏布江沿岸4种植物根际土壤中共有28门、84纲、156目、262科、599属土壤细菌,其中变形菌门、酸杆菌门、放线菌门是雅鲁藏布江岸边植物根际土壤的优势菌群,相对丰度较高,其次为拟杆菌门、芽单胞菌门、疣微菌门。在门水平上,4种植物根际土壤细菌的群落结构组成表现为黄刺玫和艾草相似,而八宝和另外三种植物相差较大。土壤细菌OTUs(操作分类单元)数和Chaol均以艾草为最高,其值分别是6695和8000.02,以白刺花为最低,其值分别是4563和5113....     

基于高通量测序的鄱阳湖典型湿地土壤细菌群落特征分析

采用高通量测序技术分析了鄱阳湖典型湿地土壤细菌群落特征。测序结果表明,不同植被土壤细菌群落丰度与多样性的排序相同:苔草带苔草-虉草带芦苇带泥滩带藜蒿带。沿湖面至坡地,空间位置相近的土壤细菌群落结构具有更大的相似性,苔草-虉草带、苔草带和芦苇带的细菌群落结构相近,泥滩带和藜蒿带的细菌群落结构差异较大。变形菌门(30.0%)是湿地土壤平均相对丰度最高的门,其次为酸杆菌门(16.7%)和绿弯菌门(16.5%);多数门分类细菌相对丰度沿湖面至坡地存在一定变化趋势。硝化螺菌属是第一大属分类水平细菌群落。在土壤化学指标中,与鄱阳湖湿地细菌群落相关性较大的是总磷、铵态氮和有机质含量。以上研究结果表明,鄱阳湖湿地不同植被土壤细菌群落具有结构性差异,但沿湖面至坡地存在规律性变化。     

新疆三个不同盐碱地区土壤沉积物中细菌多样性分析

运用高通量测序技术对新疆巴里坤湖、阿勒泰福海阿尔达乡盐湖、吐鲁番亚尔乃孜沟三个盐碱地区土壤沉积物的细菌进行序列测定和分析,发现三个不同盐碱土壤沉积物中菌落构成在门水平和属水平均存在差异,阿勒泰福海阿尔达乡盐湖土壤沉积物中物种总数最多且具有丰富的多样性,其次是巴里坤湖地区土壤沉积物,而吐鲁番地区土壤沉积物中物种总数和多样性最少,三个不同盐碱土壤沉积物中细菌的丰度、多样性差异有统计学意义(Z_(chao)=9.373,F_(shannon)=1 497.94,F_(Simpson)=159.46,P0.05)。门水平看三个不同盐碱地区土壤沉积物中共有的优势菌门为变形菌门(Proteobacteria),其次是拟杆菌门(Bacteroides),门水平上差异存在统计学意义(P0.05)。三个不同盐碱地区土壤沉积物共获得827个不同的菌属,巴里坤地区土壤沉积物气单胞菌属(Aeromonas)、热带小单胞菌属(Tropicimonas)丰度较高;阿勒泰地区是气单胞菌属丰度较高;吐鲁番地区优势菌群则是鞘氨醇单胞菌属(Sphingomonas)和柄杆菌属(Caulobacter),属水平上差异存在统计学意义(P0.05)。本研究得出三个不同盐碱地区土壤沉积物中细菌多样性在门水平和属水平细菌组成和丰度存均在差异,且具有不同的优势菌,为微生物资源开发利用及医药研发提供了前期研究基础。     

不同重金属污染水平下生物结皮及下层土壤细菌群落的差异性分析

为了探究生物结皮及下层土壤细菌群落多样性及结构在不同重金属污染水平下的差异及其影响因素,以宁夏东部工矿区和封育草地内广泛分布的两类生物结皮为研究对象,采用高通量测序技术,分析结皮层(A层)和结皮下层(B层)土壤细菌群落结构和多样性差异。采用相关分析、冗余分析探讨两个生境生物结皮各层次细菌群落与土壤环境因子的关系。结果表明：(1)相较于封育区,工矿区2类生物结皮对源自大气降尘的重金属元素具有更显著的表层富集作用,并表现出显著的种间差异：苔藓结皮>藻结皮。污染负荷指数评价结果显示：工矿区生物结皮各层次重金属污染程度更高,且均表现为A层污染程度高于B层。(2)两个生境的优势细菌门组成基本一致,均为放线菌门、变形菌门、酸杆菌门。受生物结皮类型、重金属污染程度的影响,细菌群落结构差异显著,主要表现为：工矿区藻结皮A、B层的α多样性指数均大于封育区,而苔藓结皮A、B层的细菌多样性指数高于封育区,丰富度指数低于封育区。主坐标分析结果显示,不同生境的生物结皮细菌群落结构差异明显,而同一生境的生物结皮细菌群落结构相似。重金属As、Pb、土壤黏粒含量和pH是影响生物结皮细菌群落结构的主要土壤环境因子...     

香蕉假茎生物炭对根际土壤细菌丰度和群落结构的影响

【目的】将香蕉假茎生物炭施加到土壤,探讨香蕉假茎生物炭对香蕉根际土壤微生物的影响。【方法】以香蕉假茎生物炭(BPB)0、1%、2%、3%的质量比与土壤均匀混合。盆栽培养3个月后分离香蕉根际土壤。采用16S rRNA高通量测序技术对根际土壤细菌群落结构和丰度进行表征。【结果】提高BPB施用量可增加土壤有机质、有效钾、有效磷含量,提高土壤pH值,但降低有效氮浓度。在1%BPB样品中获得2278个OTUs,其显示细菌群落中的最大多样性。施加3%的BPB处理土壤,拟杆菌门、疣微菌门和厚壁菌门的相对丰度显著增加;放线菌门、酸杆菌门、芽单胞菌门明显减少。主成分分析发现,1%BPB和2%BPB处理的样本之间土壤细菌群落相似。【结论】施加不同比例BPB改变了根际土壤中细菌丰度和群落结构,且高比例添加改变更加明显。     

真菌性外耳道炎患者耳道环境菌群结构及多样性

本研究针对广东地区真菌性外耳道炎患者,采集健康对照组以及患病组外耳道分泌物,提取其总DNA,分析其微生物群落结构、多样性变化以及真菌与细菌之间的相关关系。结果显示,对于细菌而言,致病细菌不仅存在于患病组耳道,也存在于健康人群的耳道当中;对于真菌而言,虽然健康组也检出了真菌,但与细菌不同的是,患病组与健康组的真菌群落差异显著。健康组耳道真菌以担子菌门Basidiomycota为主,该类真菌并不是真菌性外耳道炎的致病菌,而在患病组中,子囊菌门Ascomycota的曲霉属Aspergillus占据绝对优势地位。曲霉是重要的致病菌,在10个患病组样本中,8个样本的曲霉属占比超过90%。此外,真菌与细菌之间,仅有极少数菌种的丰度变化存在正相关关系,多数细菌与真菌的丰度变化并不相关,这意味着在耳道环境中,真菌与细菌群落变化的依存关系不明显。总的来说,健康人群与患病人群的耳道环境均存在致病菌,致病菌的存在并不必然导致耳道炎症的发生,菌群变化只是炎症产生的前提。而曲霉在耳道的大量繁殖是真菌性外耳道炎发病的重要原因,维持一种不利于该菌繁殖的耳道环境,可能是预防真菌性外耳道炎发病的有效措施。     

Vertical distribution of bacterial community diversity in the Greater Khingan Mountain permafrost region

Soil microorganisms are crucial contributors to the function of permafrost ecosystems, as well as the regulation of biogeochemical cycles. However, little is known about the distribution patterns and drivers of high‐latitude permafrost microbial communities subject to climate change and human activities. In this study, the vertical distribution patterns of soil bacterial communities in the Greater Khingan Mountain permafrost region were systematically analyzed via Illumina Miseq high‐throughput sequencing. Bacterial diversity in the active layer was significantly higher than in the permafrost layer. Principal coordinate analysis (PCoA) indicated that the bacterial community structure in the active layer and the permafrost layer was completely separated. Permutational multivariate analysis of variance (PERMANOVA) detected statistically significant differentiation across the different depths. The relative abundance of the dominant phyla Chloroflexi (17.92%–52.79%) and Actinobacteria (6.34%–34.52%) was significantly higher in the permafrost layer than in the active layer, whereas that of Acidobacteria (4.98%–38.82%) exhibited the opposite trend, and the abundance of Proteobacteria (2.49%–22.51%) generally decreased with depth. More importantly, the abundance of bacteria linked to human infectious diseases was significantly higher in the permafrost layer according to Tax4Fun prediction analysis. Redundancy analysis (RDA) showed that ammonium nitrogen (NH₄ ⁺‐N), total organic carbon (TOC), and total phosphorus (TP) were major factors affecting the bacterial community composition. Collectively, our findings provide insights into the soil bacterial vertical distribution patterns and major environmental drivers in high‐latitude permafrost regions, which is key to grasping the response of cold region ecosystem processes to global climate changes.     

小黑麦对石油污染盐碱土壤细菌群落与石油烃降解的影响

为了研究小黑麦对石油污染盐碱土壤中的细菌群落与石油烃降解率的影响,采用高通量测序技术,设置0 g/kg,1 g/kg和5 g/kg三个石油浓度,以未种植小黑麦的土壤作为对照,对6组不同处理的盐碱土壤样品的细菌群落结构及其多样性进行测定,并分析土壤中的石油烃降解率。结果表明:在土壤石油浓度为1 g/kg和5 g/kg时,小黑麦根际土壤中的石油烃降解率相较对照组分别提高了36.67%和33.20%。从6个土壤样品中分别获得21398—27899条测序序列。在石油污染土壤中,小黑麦根际土壤的细菌群落多样性和丰度均大于对照组的土壤。同时,在"门","纲","属"的分类水平上,小黑麦根际土壤细菌群落中的一些根际细菌的相对丰度增加了,主要包括变形菌门(Proteobacteria)、酸杆菌门(Acidobacteria)、γ-变形菌纲(Gammaproteobacteria)、烷烃降解菌科-未命名菌属(Alcanivoracaceae_norank)、黄单胞菌属(Xanthomonas)、亚硝化单胞菌-不可培养菌属(Nitrosomonadaceae_unculture)等。有一些相对丰度增加的根际细菌是以石油及石油分解物为碳源的微生物。本研究证明种植小黑麦改变了石油污染盐碱土壤根际土壤细菌群落结构组成和多样性,促进了降解石油微生物群落的构建,显著提高了盐碱土壤石油污染的降解效果。研究结果为石油污染盐碱土壤的植物修复奠定了理论基础。     

High‐throughput sequencing provides insight into manipulated soil fungal community structure and diversity during temperate forest restoration

The process of community assembly in fungal communities is poorly understood and may have important implications for restoration. However, there is a shortage of data describing fungal community composition at various stages of restoration. This study describes how microbial inoculation with field‐collected soils or a commercial inoculum influenced fungal communities during temperate tree restoration. We utilized Illumina Mi‐Seq sequencing technology to examine fungal community structure in the rhizosphere soils of trees at the conclusion of one growing season. Inoculation treatment was found to be a significant determinant of fungal community structure in one of our three experimental tree species (Liriodendron tulipifera). We also found a marginally significant influence of inoculation method on fungal community structure in the rhizosphere soils of Quercus rubra, an ectomycorrhizal tree species. Importantly, within these taxa, the use of commercial inocula, while failing to lead to detectable abundances of the inoculated taxa, strongly influenced the resulting fungal community structure after 4 months in the field, relative to control trees that received no such inoculation. We observed lower abundances of Hebeloma, a potentially important ectomycorrhizal genera, in Quercus trees receiving the commercial inoculum compared with control trees; thus, the commercial inoculum might have unexpected consequences for fungal community assembly. Such unintended legacy effects of soil inoculation should be considered in ecological restoration. Furthermore, by taking a time series approach to sampling, high‐throughput sequencing approaches could be used to test the principles of ecological assembly theory, including legacy effects of taxa no longer detectable in the community.     

黄河内蒙古段表层沉积物细菌多样性及群落结构类型

为掌握黄河内蒙古段表层沉积物微生物多样性、群落结构类型及其影响因素,采用高通量测序技术分析了6个采样点表层沉积物中的微生物多样性及群落结构。研究结果表明,黄河内蒙古段沉积物细菌丰度大小排序为乌拉特前旗(H3)老牛湾(H6)临河(H2)包头(H4)托县(H5)乌海(H1),微生物多样性排序为H6 H2 H5 H4 H3 H1,乌海沉积物中细菌丰度和微生物多样性都是最低的一个采样点。黄河内蒙古段表层沉积物中三大优势菌群分别为变形菌门(Proteobacteria,相对丰度32.39%)、绿弯菌门(Chloroflexi,13.25%)和拟杆菌门(Bacteroidetes,12.16%)。细菌群落丰度与环境因子之间的冗余分析结果显示,沉积物中总有机碳(TOC)、离子交换容量(CEC)和总磷(TP)、总氮(TN)等环境因子对黄河内蒙古段沉积物细菌群落分布影响较大,负相关系数分别为82.5%、80.1%、85.5%和85.2%;微生物多样性与环境理化因子相关性分析结果表明,黄河沉积物微生物多样性格局与对氮磷等营养物质的损耗有直接关系。     

紫茎泽兰入侵对土壤细菌的群落组成和多样性的影响

外来生物入侵可能对生物群落结构和生态系统功能产生多种影响, 但入侵植物与土壤微生物群落组成和多样性的关系尚不清楚。为了揭示外来植物紫茎泽兰(Eupatorium adenophorum)入侵对土壤化学性质和细菌群落组成及多样性的影响, 本研究利用第二代高通量测序技术, 比较了紫茎泽兰不同入侵程度的生境(本地植物群落、紫茎泽兰与本地植物混生群落、紫茎泽兰单优群落)土壤中细菌群落的差异。土壤化学性质分析表明, 土壤pH值、有机质、全N和全K随着紫茎泽兰的入侵而逐渐降低, 而土壤全P则在入侵程度最高的生境土壤中最高。通过测序共获得7,755个细菌OUT (operational taxonomic unit)。结果表明, 紫茎泽兰入侵对土壤的细菌多样性影响较小, ACE和Chao指数在3种不同生境间的差异不显著。细菌在紫茎泽兰与本地植物混生群落中的Shannon指数最低, 即细菌的多样性在中等入侵程度的生境最低。此外, 紫茎泽兰入侵改变了土壤细菌组成和结构, 酸杆菌门(Acidobacteria)和疣微菌门(Verrucomicrobia)的相对丰度, 从本地植物群落、混合群落到紫茎泽兰单优群落, 呈现出先增加后减少的趋势。可见, 紫茎泽兰入侵一定程度上改变了土壤微生物的多样性和群落结构, 并改变了土壤的化学性质。     

Dissimilar responses of fungal and bacterial communities to soil transplantation simulating abrupt climate changes

Both fungi and bacteria play essential roles in regulating soil carbon cycling. To predict future carbon stability, it is imperative to understand their responses to environmental changes, which is subject to large uncertainty. As current global warming is causing range shifts toward higher latitudes, we conducted three reciprocal soil transplantation experiments over large transects in 2005 to simulate abrupt climate changes. Six years after soil transplantation, fungal biomass of transplanted soils showed a general pattern of changes from donor sites to destination, which were more obvious in bare fallow soils than in maize cropped soils. Strikingly, fungal community compositions were clustered by sites, demonstrating that fungi of transplanted soils acclimatized to the destination environment. Several fungal taxa displayed sharp changes in relative abundance, including Podospora, Chaetomium, Mortierella and Phialemonium. In contrast, bacterial communities remained largely unchanged. Consistent with the important role of fungi in affecting soil carbon cycling, 8.1%–10.0% of fungal genes encoding carbon‐decomposing enzymes were significantly (p < 0.01) increased as compared with those from bacteria (5.7%–8.4%). To explain these observations, we found that fungal occupancy across samples was mainly determined by annual average air temperature and rainfall, whereas bacterial occupancy was more closely related to soil conditions, which remained stable 6 years after soil transplantation. Together, these results demonstrate dissimilar response patterns and resource partitioning between fungi and bacteria, which may have considerable consequences for ecosystem‐scale carbon cycling.     

基于MiSeq高通量测序技术对3个孝感凤窝酒曲细菌多样性的评价

目的 对凤窝酒曲细菌多样性进行研究。方法 选取孝感地区3个凤窝酒曲作为研究对象,采用MiSeq高通量测序技术以16S rRNA为靶点,对其细菌菌群构成进行研究。结果 3个凤窝酒曲中发现9个优势核心属,其相对含量累计为78.15%,发现10个相对含量大于1.0%的分类操作单元,累计相对含量为60.62%。结论 3个凤窝酒曲共有大量的核心细菌菌群。     

毛竹入侵马尾松林的土壤菌群多样性变化

为揭示毛竹入侵邻域林分过程中对土壤细菌群落多样性变化的影响,以马尾松林为研究对象,采集纯毛竹林、竹针混交林和常绿针叶(马尾松)混交林3类样地的混合土样,基于高通量测序技术分析土壤细菌群落多样性和结构变化.结果表明: 研究期间共得到细菌类群39门88纲134目160科511属;在门的分类水平上,与竹针混交林、常绿针叶混交林相比,纯毛竹林酸杆菌门所占比例显著较低,而放线菌门、拟杆菌门、TM7和衣原体门所占比例较高;在属的分类水平上,相对于纯毛竹林,竹针混交林和常绿针叶混交林均有多属表现出所占比例显著上升或下降,单独出现在竹针混交林或常绿针叶混交林且所占比例在0.005%～0.1%的非优势属有130属;α多样性指数均表现为常绿针叶混交林>竹针混交林>纯竹林,且纯竹林与两者均有显著差异,而常绿针叶混交林和竹针混交林之间差异不显著.PCoA分析表明,毛竹入侵对土壤细菌的种群多样性和群落结构产生了影响;所占比例小于0.1%的非优势菌群门分类水平的百分比特征与土壤环境梯度(水溶性有机氮和硝态氮)之间有显著相关性,两者对毛竹入侵马尾松林后土壤细菌群落的非优势种群影响巨大,具有重要的参考价值.