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1.
Here, we examine soil-borne microbial biogeography as a function of the features that define an American Viticultural Area (AVA), a geographically delimited American wine grape-growing region, defined for its distinguishing features of climate, geology, soils, physical features (topography and water), and elevation. In doing so, we lay a foundation upon which to link the terroir of wine back to the soil-borne microbial communities. The objective of this study is to elucidate the hierarchy of drivers of soil bacterial community structure in wine grape vineyards in Napa Valley, California. We measured differences in the soil bacterial and archaeal community composition and diversity by sequencing the fourth variable region of the small subunit ribosomal RNA gene (16S V4 rDNA). Soil bacterial communities were structured with respect to soil properties and AVA, demonstrating the complexity of soil microbial biogeography at the landscape scale and within the single land-use type. Location and edaphic variables that distinguish AVAs were the strongest explanatory factors for soil microbial community structure. Notably, the relationship with TC and TN of the <53 μm and 53–250 μm soil fractions offers support for the role of bacterial community structure rather than individual taxa on fine soil organic matter content. We reason that AVA, climate, and topography each affect soil microbial communities through their suite of impacts on soil properties. The identification of distinctive soil microbial communities associated with a given AVA lends support to the idea that soil microbial communities form a key in linking wine terroir back to the biotic components of the soil environment, suggesting that the relationship between soil microbial communities and wine terroir should be examined further. 相似文献
2.
Soil properties and habitats determine the response of bacterial communities to agricultural wastewater irrigation 总被引:1,自引:0,他引:1
Sascha M. B. KRAUSE Anja B. DOHRMANN Osnat GILLOR Bent T. CHRISTENSEN Ines MERBACH Christoph C. TEBBE 《土壤圈》2020,30(1):146-158
Increasing temperatures and variability of precipitation events due to climate change will lead in the future to higher irrigation demands in agroecosystems.However,the use of secondary treated wasterwater(TWW)could have consequences for the receiving soil environment and its resident microbial communities.The objective of this study was to characterize the importance of soil properties and habitats to the response of soil bacteria and archaea to irrigation with TWW.Two agricultural soils with contrasting textures(loamy sand or silt loam)and,for each,three variants differing in soil organic carbon and nitrogen,as generated by long-term fertilization,were analyzed.For each of these six soils,prokaryotic communities from two habitats,i.e.,root-free bulk soil and the rhizosphere of developing cucumber plants in the greenhouse,were characterized.Communities were analyzed by the quantity and diversity of their polymerase chain reaction(PCR)-amplified 16S rRNA genes.To account for TWW-associated nutrient effects,potable water(PW)served as a control.Amplicon sequence analysis showed that prokaryotic communities mainly consisted of bacteria(99.8%).Upon irrigation,regardless of the water quality,prokaryotic diversity declined,p H increased,and no bacterial growth was detected in bulk soil.In contrast,the growth of cucumbers was stimulated by TWW,indicating that plants were the main beneficiaries.Moreover,strong responses were seen in the rhizosphere,suggesting an indirect effect of TWW by altered rhizodepositions.The main bacterial responders to TWW were Proteobacteria,Bacteroidetes,Actinobacteria,and Planctomycetes.Changes in bacterial communities due to TWW were less pronounced in all variants of the silt loam,indicating the importance of clay and soil organic carbon for buffering effects of TWW on soil bacterial communities.Hence,soil organic carbon and soil texture are important parameters that need to be considered when applying TWW in agriculture. 相似文献
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模拟干湿交替对水稻土古菌群落结构的影响 总被引:2,自引:0,他引:2
干湿交替是自然界普遍存在的现象,但长期以来由于技术的限制,复杂土壤中微生物对水分变化的响应规律仍不清楚。针对我国江苏常熟湖泊底泥发育的典型水稻土,在室内开展湿润-风干以及风干-湿润各三次循环,每次循环中湿润、风干状态各维持7d,利用微生物核糖体rRNA的通用引物进行PCR扩增,通过高通量测序分析土壤古菌多样性变化,同时结合实时荧光定量PCR技术,在DNA和RNA水平研究古菌数量对干湿交替过程的响应规律。结果表明:水稻土湿润-风干过程中,在DNA水平土壤古菌数量降幅约为149倍~468倍,而在RNA水平降幅最高仅为2.06倍;水稻土风干-湿润过程中,在DNA水平古菌数量增幅在147倍~360倍之间,而在RNA水平增幅最高仅为2.95倍。表明在干湿交替过程中,DNA水平的古菌16S rRNA基因数量变化远高于RNA水平。基于高通量测序多样性的结果表明,在DNA和RNA水平,湿润土壤3次风干、以及风干土壤3次加水湿润7d恢复后,土壤古菌群落结构均发生统计显著性改变。在微生物门、纲、目、科和属的不同分类水平下,水稻土古菌主要包括3、10、13、14、10种不同的类群,在RNA和DNA水平的结果基本一致。干湿交替导致部分古菌类群发生显著变化,其中在微生物分类学目水平发生显著变化的古菌最高达到6种,主要包括产甲烷古菌和氨氧化古菌,如Methanobacteriales、Methanosarcinales、Methanomicrobiales和Nitrososphaerales等。这些研究结果表明,反复的干湿交替并未显著改变水稻土中古菌的主要类群组成,古菌类群的绝对数量和相对丰度发生了一定程度的变化,但这些变化与微生物生理作用的联系仍需进一步研究;风干土壤中古菌RNA序列极可能来自于完整的古菌细胞,暗示了这些古菌细胞能够较好地适应水稻土中水分的剧烈变化,风干状态的土壤在一定程度也可用于土壤古菌群落组成研究。 相似文献
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Soil microbial communities in dryland ecosystems play important roles as root associates of the widely spaced plants and as the dominant members of biological soil crusts (biocrusts) colonizing the plant interspaces. We employed rRNA gene sequencing (bacterial 16S/fungal large subunit) and shotgun metagenomic sequencing to compare the microbial communities inhabiting the root zones of the dominant shrub, Larrea tridentata (creosote bush), and the interspace biocrusts in a Mojave desert shrubland within the Nevada Free Air CO2 Enrichment (FACE) experiment. Most of the numerically abundant bacteria and fungi were present in both the biocrusts and root zones, although the proportional abundance of those members differed significantly between habitats. Biocrust bacteria were predominantly Cyanobacteria while root zones harbored significantly more Actinobacteria and Proteobacteria. Pezizomycetes fungi dominated the biocrusts while Dothideomycetes were highest in root zones. Functional gene abundances in metagenome sequence datasets reflected the taxonomic differences noted in the 16S rRNA datasets. For example, functional categories related to photosynthesis, circadian clock proteins, and heterocyst-associated genes were enriched in the biocrusts, where populations of Cyanobacteria were larger. Genes related to potassium metabolism were also more abundant in the biocrusts, suggesting differences in nutrient cycling between biocrusts and root zones. Finally, ten years of elevated atmospheric CO2 did not result in large shifts in taxonomic composition of the bacterial or fungal communities or the functional gene inventories in the shotgun metagenomes. 相似文献
6.
Zhenhua Yu Xiaojing Hu Dan Wei Junjie Liu Baoku Zhou Jian Jin 《Archives of Agronomy and Soil Science》2019,65(10):1331-1340
The effects of chemical fertilizers on soil microbial communities have been well studied in a variety of terrestrial systems. However, the individual effects of N, P, and K fertilizers and their combinations (NP, NK, PK and NPK) on bacterial community structure in black soils have not been fully understood. In this study, we applied Illumina MiSeq sequencing and network analysis targeting 16S rRNA gene to comprehensively characterize the effects of 35 years of these inorganic fertilizers on community diversity and composition in the black soil. The results of α-diversity indices and principal coordinates analysis (PCoA) indicated that the N-addition treatments had larger effects than the others. The network analysis showed that the N fertilizer shifted the network structure, topological roles of individual OTUs and key bacterial populations, contributing to a simple network under the N-fertilizer treatments compared with non-N fertilizers treatments. These findings suggested that N fertilizer reduced the bacterial diversity and simplified the interactions among key bacterial members in Mollisol. The results of this study could provide basis for further researches balancing different N application levels, the bacterial community network and crop yield to maintain the ecosystem function and stability.
Abbreviations: N: nitrogen fertilizer; P: phosphorus fertilizer; K: potassium fertilizer; NP: nitrogen and phosphorus fertilizers; NK: nitrogen and potassium fertilizers; PK: phosphorus and potassium fertilizers; NPK: phosphorus and potassium fertilizers; TC: total carbon; TN: total nitrogen; TP: total phosphorus; TK: total potassium; AP: available phosphorus; AK: available potassium; OTUs: operational taxonomic Units; ACE: abundance-based coverage estimator; Chao1: estimated OTU richness; PCoA: principal coordinates analysis 相似文献
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M. Salvador-Figueroa V. M. Ruíz-Valdiviezo M. A. Rogel-Hernandez F. A. Gutiérrez-Miceli C. I. Rincón-Molina L. Dendoveen 《Journal of plant nutrition》2016,39(10):1449-1459
A diazotrophic bacterial strain denominated 11B isolated from the rhizosphere of a banana plant (Musa spp.) was characterized morphologically, biochemically, and phylogenetically, whereas the symbiotic potential of the strain was assessed through tests of host range, interstrain nodulation competitiveness, and capacity to synthesize indole-3-acetic acid (IAA) and solubilize phosphate. Based on morphological and physiological–biochemical properties, as well as 16S ribosomal deoxyribonucleic acid (rDNA) sequence and phylogenetic analysis, the strain 11B belonged to the genus Rhizobium with 100.0% sequence similarity with Rhizobium tropici CAF440. The optimum growth temperature and pH for strain 11B are 28°C and 7.2, respectively. This strain was able to produce IAA, solubilize phosphate, and fix large amounts of nitrogen (N2) and form effective nodules on the legumes Acaciella angustissima, Gliricidia sepium, Leucaena leucocephala, Lysiloma acapulcensis, and Phaseolus vulgaris. The rhizobial strain 11B was used successfully as a biofertilizer in agriculturally important legumes, forest trees, and agroindustrial plants. 相似文献
9.
The diversity of endobacteria associated with ectomycorrhizas of Suillus variegatus and Tomentellopsis submollis, in two Corsican pine (Pinus nigra) stands was analysed by cultivation-dependent and cultivation-independent molecular methods. Denaturing gradient gel electrophoresis (DGGE) analysis revealed the cultivable endobacterial communities associated with S. variegatus were similar within the same stand. The most abundant cultivable bacterial species belonged to the genera Pseudomonas and Burkholderia. Cultivation-independent molecular analysis indicated that the structure of the endobacterial communities in ectomycorrhizas was consistent across all samples regardless of ECM fungal species or the pine stand from which the samples were collected. However, comparison between rDNA- and rRNA-derived DGGE gels showed that metabolically active endobacterial species were not always detected in rDNA-based profiles. Clone libraries constructed from rRNA molecules indicated that Pseudomonas and Burkholderia spp. were metabolically active bacteria. As some of the most abundant cultivable bacteria, including Bacillus/Paenibacillus spp., were not detected in cultivation-independent DGGE profiles, a combination of cultivation-dependent and -independent approaches provided a more complete assessment of the diversity of endobacteria associated with ectomycorrhizas. 相似文献
10.
潮棕壤不同利用方式pH和Olsen-P的垂直变化特征 总被引:8,自引:3,他引:8
对潮棕壤4种土地利用方式经过14年后土壤pH和Olsen-P在0~150cm土体10个土层中的垂直分布情况进行的比较研究表明,不同利用方式下土壤pH和Olsen-P含量的剖面分布差异显著,说明不同利用方式对土壤pH和Olsen-P有较大影响。林地和撂荒地0~5cm土层pH分别为>7.0和6.5~7.0,玉米地0~20cm各土层土壤pH基本为6.0以下;20cm以下各土层中的pH,水稻田土壤呈微碱性,玉米地和撂荒地接近中性,林地呈微酸性。土体中Olsen-P平均含量为撂荒地>林地>水稻田>玉米地。水稻田和玉米地0~20cm的3个土层Olsen-P含量明显高于20~80cm的4个土层,表明耕地土壤由于施P肥而导致的P素表聚性;林地和撂荒地0~5cm土层的Olsen-P含量大大高于5~80cm的6个土层,这可能与林地和撂荒地的P素生物归还及基本不受人为扰动有关。4种土地利用方式下土壤各层次Olsen-P含量垂直分布的散点折线图呈现出较为相似的特征。80cm以下的3个土层Olsen-P含量接近或超过表层土壤,主要是受母质层相对较高的全P含量影响所致,也可能与地下水作用有关,不过具体原因还有待于进一步研究。 相似文献
11.
黄土高塬沟壑区退耕地土壤抗冲性及其与影响因素的关系 总被引:9,自引:2,他引:9
为了评价退耕地土壤抗冲性的变化,该文以黄土高塬沟壑区自然退耕农地为研究对象,通过径流小区冲刷法对不同覆盖度塬面退耕地(TAL,table-land abandoned land)和沟头退耕地(GAL,gully-head abandoned land)土壤抗冲性进行了研究。结果表明,1)与对照(Ⅰ)相比,TAL和GAL处理水稳性团聚体、根系密度和根系生物量均显著增加(P0.05),覆盖度大于0时,崩解速率显著减小44.87%~79.16%和33.79%~70.65%,有机质显著增加70.12%~222.70%和59.20%~194.88%,覆盖度最大时,土壤容重和渗透系数才显著减小和增大。2)TAL处理0覆盖度小区抗冲系数(AS,anti-scouribility)较对照无差异,其余覆盖度则显著增大2.31~7.57倍,GAL处理AS较对照显著增大0.99~7.12倍,覆盖度越大,根系提高土壤抗冲性能的效果越显著。3)TAL和GAL处理AS分别与容重、崩解速率、水稳性团聚体含量、渗透系数均呈极显著指数函数关系,与有机质含量、根系生物量及根系密度均呈极显著线性函数关系。水稳性团聚体是影响塬面和沟头退耕地土壤抗冲性的关键因子。结果可为研究区退耕还林还草工程生态功能评价及水土流失治理提供理论依据。 相似文献
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Community structure of methanogenic archaea in paddy field soil under double cropping (rice [Oryza sativa L.] and wheat [Triticum aestivum L.]) was studied by the denaturing gradient gel electrophoresis (DGGE) method. Soil samples under flooded and upland conditions were collected 7 and 6 times, respectively, from two paddy fields throughout a year, and two primer sets, 0357F-GC/0691R and newly designed 1106F-GC/1378R, were used for DGGE analysis. The 25 and 29 different bands were observed on the DGGE gels with the primers 0357F-GC/0691R and 1106F-GC/1378R, respectively. DGGE band patterns of the methanogenic archaeal community were stable throughout a year including the cultivation periods of rice under flooded conditions and of wheat under upland conditions. Cluster analysis and principal component analysis suggested that the difference in the soil type (sampling region) largely influenced the community structures of methanogenic archaea in paddy field soil, while the effects of sampling period and different fertilizer treatments on them were small. Most of the sequences obtained from the DGGE bands were closely related to Methanomicrobiales, Methanosarcinaceae, Methanosaetaceae and Rice cluster-I. 相似文献
13.
The study of interactions between minerals, organic matter (OM) and microorganisms is essential for the understanding of soil functions such as OM turnover. Here, we present an interdisciplinary approach using artificial soils to study the establishment of the microbial community and the formation of macro-aggregates as a function of the mineral composition by using artificial soils. The defined composition of a model system enables to directly relate the development of microbial communities and soil structure to the presence of specific constituents. Five different artificial soil compositions were produced with two types of clay minerals (illite, montmorillonite), metal oxides (ferrihydrite, boehmite) and charcoal incubated with sterile manure and a microbial community derived from a natural soil. We used the artificial soils to analyse the response of these model soil systems to additional sterile manure supply (after 562 days). The artificial soils were subjected to a prolonged incubation period of more than two years (842 days) in order to take temporally dynamic processes into account. In our model systems with varying mineralogy, we expected a changing microbial community composition and an effect on macro-aggregation after OM addition, as the input of fresh substrate will re-activate the artificial soils. The abundance and structure of 16S rRNA gene and internal transcribed spacer (ITS) fragments amplified from total community DNA were studied by quantitative real-time PCR (qPCR) and denaturing gradient gel electrophoresis (DGGE), respectively. The formation of macro-aggregates (>2 mm), the total organic carbon (OC) and nitrogen (N) contents, the OC and N contents in particle size fractions and the CO2 respiration were determined. The second manure input resulted in higher CO2 respiration rates, 16S rRNA gene and ITS copy numbers, indicating a stronger response of the microbial community in the matured soil-like system. The type of clay minerals was identified as the most important factor determining the composition of the bacterial communities established. The additional OM and longer incubation time led to a re-formation of macro-aggregates which was significantly higher when montmorillonite was present. Thus, the type of clay mineral was decisive for both microbial community composition as well as macro-aggregation, whereas the addition of other components had a minor effect. Even though different bacterial communities were established depending on the artificial soil composition, the amount and quality of the OM did not show significant differences supporting the concept of functional redundancy. 相似文献
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CHEN Xue-Ping ZHANG Xuan-Xuan ZHU Xi-E ZHANG Hui LIANG Xi LEI Yan-Ru HE Chi-Quan 《土壤圈》2016,26(1):108-119
Alnus trabeculosa, a rhizobia-nodulating tree, was introduced into the Chongxi tidal wetland in the Yangtze River estuary of China to increase the biodiversity of plants and restore tidal wetland functions. However, the effect of the introduced plant on soil bacterial communities and restoration outcomes remains unknown. In this study, the rhizosphere bacterial community structure and diversity were compared between Phragmites australis monospecific community and A. trabeculosa-P. australis mixed communities,aiming to assess whether A. trabeculosa influenced the rhizosphere bacterial communities of P. australis and to investigate whether different taxonomic groups within a soil community may respond similarly to the presence of an introduced exotic plant. Among the14 phylogenetic phyla detected, Proteobacteria and Acidobacteria were the dominant bacterial taxa in the rhizosphere. Phylogenetic analysis of the predominant Proteobacteria showed that the clones from the rhizosphere soils of A. trabeculosa and P. australis in A. trabeculosa-P. australis mixed communities were more diverse than those in the rhizosphere soil of P. australis in P. australis monospecific community. The rhizosphere community in the wetland potentially included active microbial community related to carbon, nitrogen, and sulfur cycling in the Yangtze River estuary. The rhizosphere soil of P. australis in A. trabeculosa-P. australis mixed communities exhibited the highest Shannon diversity index(H′) and Simpson diversity index(1/D)(H = 4.52, 1/D =253). Correspondence analyses revealed that the bacterial community structures were altered after A. trabeculosa was introduced. 相似文献
15.
利用土壤定位采样分析了富阳市不同土地利用方式和土壤特征对全量和有效态Zn在土壤中累积的影响.分析结果表明,工业用地与农业用地中的全量和有效态Zn差异极显著,工业用地方式土壤全量和有效态Zn含量较高;在农用地方式中,菜地、旱地、水田和林地的全量Zn累积程度相近,但与果园和茶园差异显著;不同农业用地中的有效态Zn无显著差异.并对农业与工业用地方式下全量Zn、土壤特征与有效态Zn含量之间的相关关系进行了分析.结果表明,在农业用地中,全氮、有机质和pH对Zn全量影响显著,而全量、有效磷和速效钾对Zn有效态影响显著;在工业用地中,土壤理化性质对全量和有效态Zn含量无明显影响,有效态Zn含量只与全量Zn含量显著相关.基于Zn有效态的指示Kriging评价结果显示,富阳市有5.56%的土地和5.99%的耕地处在较高的Zn污染风险水平(>0.100). 相似文献
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In tropical, low‐fertility soils, crop yields are dependent on soil carbon, and cropping systems under no‐till can increase soil C stocks. Plant residues supplied by cover crops in no‐till systems may improve aggregate stability and soil carbon, which may be further increased with the introduction of a legume in the cropping system. This research studied the effects of cover crops in rotation with soybean under no‐till on soil carbon and nitrogen, in Botucatu, Brazil, for 3 yr. The cover crops were millet (Penninsetum americanum Leek), cober crop (Sorghum bicolor × Sorghum sudanense) and sunn hemp (Crotalaria juncea L.), grown in the spring. Fallow without cover crops was used as a control. Grain sorghum (Sorghum bicolor L. Moench) and soybean (Glycine max (L.) Merril) were grown in fall–winter and summer, respectively. Generally, cover crops increased soil carbon contents, but soil N was only increased by sunn hemp in the particulate organic C fraction. An increase in the labile carbon fraction in the topsoil layers was closely related to cover crop root development. Fallow in spring should not be recommended in degraded soils with lowcarbon stock. Labile‐fractioned soil organic carbon and total carbon levels are more efficiently increased by grasses than by legumes in the short term, and grasses cropped in spring increase soil C/N ratio. Conversely, the introduction of a legume (sunn hemp) maintained a more stable C/N ratio, that is around 10, which would be more effective in increasing soil C in the long term. 相似文献
17.
不同土地利用方式下土壤养分的分布及其与土壤颗粒组成关系 总被引:65,自引:9,他引:65
对四川紫色土区不同土地利用方式下土壤表层及剖面养分的分布特征及其与颗粒含量之间的关系进行了研究,结果表明:(1)林地、水田具有较高的土壤氮素和有机质(与旱地、果园、裸地均达到了显著差异),且林地剖面养分随土层深度的增加呈几何级数下降,但土壤磷素含量相对较低。(2)受施肥状况的影响,经济园林土壤磷素普遍偏高。(3)旱坡地的表层养分与底层养分含量差异不大,说明该区旱坡地土壤可能存在较大的养分流失与淋失现象,坡面径流、壤中径流携带的养分不容忽视。(4)土壤中大部分养分含量与土壤颗粒含量之间有一定的相关性,其中土壤全氮、碱解氮与粉粒(0.002~0.02mm)含量之间呈显著的正相关,与砂粒(0.02~2mm)含量之间呈极显著的负相关;土壤有机质与粉粒含量之间呈极显著的正相关,与砂粒含量之间呈极显著的负相关;而土壤全磷情况正好相反,与粉粒含量呈现极显著的负相关,与砂粒含量呈现极显著的正相关;只有碱解氮与粘粒(<0.002mm)含量之间的相关性达到了5%显著水平。 相似文献
18.
Chang-Chai Ng Chen-Chin Chang Tseng-Wei Chen Yuan-Tay Shyu 《Soil biology & biochemistry》2006,38(2):342-348
Tufa is a carbonate sediment contains inorganic and organic substances such as algae, microorganism and invertebrate. Microbial diversity of tufa found in Taroko National Park was investigated using 16S rRNA cloning and fluorescent in situ hybridization (FISH). Eleven 16S rRNA phylotypes and 37 genus and group of bacteria were identified. Of total 381 clones isolated, proteobacteria occupied 25-30% whereas cyanobacteria dominated 16-28% in total microbial population in the three sites. Acidobacteria, agricultural soil bacterium, verrucomicrobia and firmicutes were, generally, distributed in the three sampling sites. Among the three sampling sites, Baiyang walkway is found to be the most diverse site in its tufa microbial composition, indicated by species richness plot and FISH. 相似文献
19.
Peter N. Holmsgaard Anders Norman Pernille H.B. Poulsen Waleed Abu Al-Soud Søren J. Sørensen 《Soil biology & biochemistry》2011,43(10):2152-2159
Nycodenz density centrifugation (NDC) is an isolation method that allows extraction of both culturable and unculturable bacterial cells from soil, to be used in further downstream analysis; however, to date there has been a lack of information concerning the efficiency of this method. The aim of this study was therefore to investigate the overall efficiency of NDC extractions from soil and to identify sampling bias, if any.Bacterial cells were extracted from three soil plots from the Danish CRUCIAL field trial using an already established NDC protocol. To evaluate all aspects of the NDC procedure, DNA was extracted directly from soil, from NDC-extracted cells, and from the soil pellets left after NDC. Bacterial diversity was assessed by PCR amplification of the V4-V6 regions of the 16S rRNA from the extracted DNA followed by sample-tagged amplicon-pyrosequencing using the 454 Genome Sequencer FLX system. Sequences were processed and analyzed using the Ribosomal Database Project’s (RDP) Pyrosequencing Pipeline tools.In this study, we show that extraction of bacteria from soil using NDC can result in significant biases in the form of either over- or underrepresentation of specific bacterial phyla commonly found in soil. Furthermore, rarefaction analysis, analysis of similarity, multidimensional scaling plots and analysis of variance showed that the diversity in the NDC-extracted sample was reduced significantly compared to both the original soil sample and the remaining NDC-pellet. To further study the soil diversity a mathematical model was employed to estimate how many sequences would be required in order to find 95% of all operational taxonomic units (OTUs) in the soil. The model estimated that the soil contains approximately 29,400 OTUs and that just 351,500 sequences are needed to cover 95% of the bacterial biodiversity, the equivalent of one full standard GS FLX run. 相似文献
20.
本研究通过对长期保存的土壤标本中甲烷氧化菌的复苏和富集培养,明确了活性甲烷氧化菌类群及其氧化甲烷潜力,同时分析了对长期干旱胁迫有较强抗逆性的甲烷氧化菌种类。研究主要针对自然风干保存83~87年的采集自福建龙岩荒地、江西南昌水田、四川华阳旱地、甘肃榆中林地、青海湟源和青海都兰牧场的6个土壤标本进行了高浓度甲烷条件下的微宇宙培养,利用气相色谱法测定了甲烷气体浓度动态变化情况以研究其甲烷氧化能力;在获得富集培养物后提取基因组DNA,利用16S rRNA和pmo A基因高通量测序分析了整体微生物和甲烷氧化菌的群落结构;同时,利用两种基因的长片段克隆测序对优势甲烷氧化菌序列进行了系统发育分析。结果显示:经过短暂的复苏,6例土壤档案样品均表现出强烈的甲烷氧化活性,前两代富集液甲烷氧化速率较慢,甲烷氧化速率仅为1.4~3.8μg/(mL·h),而第三代富集液的甲烷氧化速率达到了4.9~7.7μg/(mL·h)。其中,福建龙岩、江西南昌、青海都兰3个样品的富集物还可以将高浓度甲烷持续氧化到大气甲烷浓度(1.8μL/L)以下。高通量测序结果表明,6种富集物中甲烷氧化菌在细菌总量中的占比为39%~85%;... 相似文献