宁夏西吉县养牛场粪污和周边土壤重金属及细菌群落特征

为了解宁夏肉牛养殖场粪污和周边土壤中重金属及细菌群落状况,在宁夏最大的肉牛养殖区西吉县采集了不同养殖期(哺乳期、犊牛期、育成期、育肥前期和育肥后期)的牛粪、施用牛粪蔬菜地及养殖场周边不同距离土壤样品,以远离养殖场的荒地土壤为对照,测定了7种重金属(Cu、Zn、Pb、Cd、Cr、Hg、As)含量和细菌群落组成及多样性。结果表明: 1)牛粪中Cu、Zn、Cd、Pb和Hg含量较全国平均值低33.8%～95.8%,而As含量比全国平均值高94.7%。随着养殖期的推移,牛粪中各重金属含量变化趋势不完全相同,育肥前期Cu、Cd、Hg和Cr含量高于其他4个时期,育肥前期和育肥后期牛粪重金属综合污染指数较大。2)施用牛粪的土壤Cu、Zn和Hg含量显著高于对照土壤,Zn含量与养殖场周边土壤差异显著,其他元素无显著差异,所有土壤重金属污染指数均在安全范围内。3)随着养殖期的推移,牛粪细菌多样性指数无特定变化趋势。施用牛粪的土壤序列、分类单元、Chao1指数显著高于养殖场周边土壤。4)牛粪中厚壁菌门的相对丰度最大,其次为拟杆菌门和变形菌门;育成期厚壁菌门的丰度显著低于其他养殖期,其他各菌门的丰度在不同养殖期间无显著差异。养殖场的存在对其周边土壤细菌群落的影响不明显,但施用牛粪后土壤Gp6、芽单胞菌属、溶杆菌属和Subdivision3_genera_incertae_sedis的数量显著高于对照和养殖场周边土壤。5)牛粪中有机质、pH、电导率、全氮、全钾、Cd、As含量对细菌多样性和各组分丰度的影响较显著;养殖场周边土壤pH、全磷和Hg含量对细菌多样性和各组分丰度的影响较显著。整体来讲,牛粪和土壤的理化性质对细菌群落的影响比重金属更显著。研究结果可为当地肉牛养殖饲料和兽药种类的选择、用量及有机肥的科学利用提供参考。     

土壤中钾细菌的筛选及筛选底物加入量对其数量的影响

研究土壤中加入不同数量的钾长石粉后其解钾细菌数量的变化,同时初步筛选钾细菌,为进一步研究土壤中解钾细菌的分离、筛选及其鉴定提供参考。测试土壤中加入不同数量的钾长石粉后其解钾细菌数量,对结果进行比较分析;利用四苯硼钠法测试菌株解钾能力,并进行初步筛选。结果表明,按钾细菌数量由多到少的顺序,筛选底物加入量为0.2%0.1%0.4%空白对照;筛选菌株的解钾效率高于K01的共14株,高于K02的共9株。解钾效率最高的菌株5.15-2解钾效率为35.4%,较外购生产菌种K01高13倍,与本实验室保存菌种K02相比高3.6倍。     

酸性土壤中耐铝细菌的筛选鉴定及其耐铝能力分析

以含有1mmol／LAl3＋的s—LB培养基作为筛选培养基,从酸性土壤中分离到13株耐铝的细菌菌株,选取其中6株进行形态学分析,结果观察到这些菌株的菌体均呈杆状,其中1株为革兰阳性反应,其余5株为革兰阴性反应。以细菌通用引物扩增这些菌株的16SrDNA并测序,将得到的序列与GenBank中的序列进行BLAST比对,利用MEGA4．0软件,按照Neighbor-joining法构建系统进化树,这6个菌株分别与Enterobacter endosymbiont,Serratia marcescens ,Pantoea agglomerans ,Enterobacter aerogenes .Bacillus subtilis 和 Enterobacter asburiae的亲缘关系最近。将这些菌株接种到加有2mmol／LAl3＋、pH4．5的s—LB固体培养基上培养时,它们都能生长,说明这些菌株具有较好的耐铝能力,这些菌株为进一步研究细菌的耐铝机制提供了极好的材料。     

珠穆朗玛峰北坡可培养石生细菌多样性及抗紫外辐射能力

【背景】珠穆朗玛峰地区具有寒冷低温、强辐射等极端环境条件,珠穆朗玛峰北坡石生微生物研究未见报道。【目的】针对珠穆朗玛峰北坡石生微生物开展研究,阐明珠穆朗玛峰北坡石生生境中可培养细菌多样性,开发珠穆朗玛峰北坡抗紫外辐射菌株资源。【方法】通过可培养法、16S rRNA基因序列分析方法以及紫外辐射筛选对珠穆朗玛峰北坡可培养石生细菌多样性以及抗紫外辐射能力进行研究。【结果】从珠穆朗玛峰北坡石生生境中共分离获得52株石生细菌,归类为放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)和拟杆菌门(Bacteroidetes),其中放线菌门和变形菌门为优势菌门,鞘脂单胞菌属、节杆菌属、链霉菌属为优势菌属,有2株菌为潜在新种。从已分离鉴定菌株中筛选出了2株抗紫外辐射能力较高的菌株,分别是芽孢杆菌属菌株ZFBP4009和链霉菌属菌株ZFBP1009。【结论】珠穆朗玛峰北坡石生环境蕴含多样性丰富的石生细菌,所分离菌株抗紫外辐射能力突出,为揭示相关极端环境下微生物的分布特征及极端环境微生物资源开发提供了数据支持及菌株资源。     

香蕉根际土壤解磷细菌的筛选、鉴定及解磷能力

【目的】以磷矿粉为难溶态磷,以期从香蕉根际土壤筛选出高效的解磷细菌。【方法】采用透明圈法和钼锑抗比色法分离筛选解磷细菌,通过形态学特征、生理生化试验结合16S rRNA基因序列分析及系统发育树比对鉴定其种属,并利用单因素试验方法研究不同碳源、氮源及C/N比值(40:1、20:1和8:1)对菌株溶解磷矿粉能力的影响。研究不同菌株解磷能力和培养介质pH值的变化关系。【结果】分离具有解磷能力的细菌8株,筛选出具有代表性的3个菌株B3-5-6、M-3-01和T1-4-01,初步鉴定菌株B3-5-6为嗜气芽孢杆菌(Bacillus aerophilus),M-3-01为虫内生沙雷氏菌(Serratia nematodiphila),T1-4-01为艾博丽肠杆菌(Enterobacter asburiae)。B3-5-6解磷能力与介质pH值之间存在线性负相关性(|r|=0.949 66>0.735),其相关性达到极显著水平;B3-5-6在碳源为蔗糖、氮源为(NH4)2SO4、C/N为40:1,M-3-01在碳源为葡萄糖、氮源为(NH4)2SO4、C/N为20:1,T1-4-01在碳源为乳糖、氮源为蛋白胨、C/N为20:1条件下解磷效果较好。解磷效果与初筛相比分别提高了1.12、1.17、2.55倍。【结论】不同的碳氮源、C/N值会直接影响磷细菌的解磷能力;筛选出一株解磷能力与培养介质pH之间存在着极显著相关性的细菌,其解磷机理有待进一步研究。     

抗草甘膦转基因大豆（RRS）对根际土壤细菌数量和多样性的影响

为深入研究种植抗草甘膦转基因大豆的黑土生态区根际土壤中细菌数量及多样性的变化,试验采用DGGE-cloning测序技术与传统培养相结合的方法,研究了抗草甘膦转基因大豆(RRS)对根际土壤细菌数量以及细菌群落多样性的影响.传统培养试验结果为RRS显著降低了土壤细菌的数量;DGGE图谱分析表明,RRS根际土壤细菌16SrDNA条带数、多样性指数及均匀度指数均要低于其他处理,聚类分析显示RRS带谱与RRS-S和Y-S差异较大,相似性分别为64%和64.4%;DGGE-cloning测序结果表明,在RRS处理中缺失条带1和条带12分别属于Uncultured bacterium和Nitrospira门Nitrospira属,其中条带1与其他切取条带最小遗传距离达0.4,与其他处理相比表现出弱势差异的条带2、4、5和条带11均属于Uncultured bacterium.研究表明,RRS不同程度上降低了根际土壤细菌的数量和细菌群落的多样性,并对根际土壤中Nitrospira属细菌有一定的抑制作用.     

南通沿海滩涂耐盐植物重金属抗性内生细菌的筛选及生物多样性

【目的】沿海滩涂耐盐植物重金属抗性内生细菌的筛选及其促生长潜在能力的研究有助于我们获得一些能够耐受并促进耐盐植物在被Cd2+、Pb2+、Hg2+、Cu2+,Zn2+等重金属离子污染的贫瘠的沿海滩涂上正常生长的菌株,达到既能够利用广袤的滩涂生物资源产生经济价值又能够净化生态环境的目的。【方法】以江苏南通沿海滩涂地区的4种耐盐植物为材料,采用稀释平板涂布法从中分离得到45株内生细菌,从中挑取23株代表性的菌株,对其进行抗重金属Cu2+、Pb2+、Cd2+、Zn2+,Hg2+的活性筛选;固氮、解磷、吲哚乙酸(IAA)的产生、1-氨基环丙烷-1-羧酸(ACC)脱氨酶活性等促生指标以及NaCl耐受能力的筛选。【结果】发现分离所得的大多数细菌能够耐受高浓度的Cu2+以及Pb2+,但是对Cd2+、Zn2+,Hg2+的耐受能力则较弱;26.1%的细菌具有固氮能力,21.7%的细菌具有解磷能力,60.9%的细菌能够产生IAA,39.1%的细菌含有ACC脱氨酶。对他们进行16S rRNA基因鉴定后发现,他们分属于芽胞杆菌属(Bacillus)、喜盐芽胞杆菌属(Halobacillus)、海洋芽胞杆菌属(Oceanobacillus)、微小杆菌属(Exiguobacterium)、沙雷氏菌属(Serratia)、短波单胞菌属(Brevundimonas)、弧菌属(Vibrio)、葡萄球菌属(Staphylococcus)共8个属,显示了丰富的多样性。其中菌株KLBMP 2432以及菌株KLBMP 2447为潜在的新种。【结论】沿海滩涂地区的耐盐植物内生细菌具有丰富多样的生物多样性以及促生长能力,且存在潜在的新种资源,并对重金属Cu2+,Pb2+具有较强的抗性。     

植被生化组分光谱模型抗土壤背景的能力

应用LOPEX'93(Leaf Optical Properties Experiment)数据,分析了统计回归模型在进行植被叶绿素和水分反演中抗土壤背景影响的能力,模型参数分别使用了:反射率及其变化形式、光谱位置变量、植被指数。在LOPEX'93数据库的植被波谱中分别加入10%—90%的实测土壤光谱信息,得到植被与土壤的混合光谱,并分析混合光谱对植被生化组分的响应。结果表明:应用反射率及其变化形式进行植被叶绿素反演时,以730nm和400nm组合的反射率和反射率倒数的对数为参数的模型具有最高的抗土壤背景能力,在土壤背景所占比例从低到高的变化过程中,以二者反射率组合为参数的模型与叶绿素的相关系数,始终保持在0.645附近,以二者反射率倒数的对数为参数的模型与植被叶绿素的相关系数保持在0.650附近;应用反射率及其变化形式进行植被含水量反演时,以1100,1170,1000,1040,1080nm组合的反射率为参数的模型以及以1170,960,1210,1090,1080,950,1220,1210nm反射率倒数的对数组合为参数的模型具有较高的稳定性,在土壤组分变化的过程中,以上模型与植被含水量的相关系数均稳定...     

解有机磷细菌对滇重楼根茎、须根及根际土壤重金属元素的影响CSCD

探究接种不同解有机磷细菌后滇重楼根茎、须根及根际土壤中重金属残留量的变化规律,为滇重楼人工种植过程中重金属污染修复提供参考。通过室内盆栽接种试验,研究了在灭菌土壤接种不同解有机磷细菌对滇重楼根茎、须根及根际土壤中汞(Hg)、镉(Cd)、铅(Pb)、铬(Cr)、砷(As)5种重金属残留量的影响。与对照组(CK组)相比,接种不同解有机磷细菌对滇重楼根茎及须根中5种重金属残留量影响各不相同,对重金属Pb的修复效果最明显,其中三种菌(Bacillus mycoides、B.wiedmannii、B.proteolyticus)混合处理组(S7组)对滇重楼重金属的修复效果最佳。此外,单项污染指数和内梅罗污染指数表明,除B.mycoides处理组的土壤存在污染风险以外,其余处理组均达到清洁水平。同时,5种重金属元素在滇重楼根茎和须根中的富集能力各不相同,富集系数最大为Cd,最小为Cr, S7组滇重楼根茎中的富集能力相对较小。相关性分析表明,滇重楼根茎和须根中的Hg和Pb元素呈显著正相关(P<0.05),相关系数分别为0.761、0.811。综上,接种解有机磷细菌能够有效降低滇重楼根茎及须根中Hg、Pb和Cr元素的含量,其中S7组接种处理的效果最佳。     

半干旱黄土区植被恢复对土壤团聚体稳定性及抗侵蚀能力的影响

土壤水稳性团聚体强烈影响土壤过程和功能,是反映土壤质量和土壤抗侵蚀能力的重要指标。为探究半干旱黄土区植被恢复对土壤抗侵蚀能力的影响,以甘肃省定西市龙滩流域为研究区,选取3种恢复方式（天然荒草、自然恢复、人工恢复）7种植被类型（大针茅草地、长芒草草地、赖草草地、苜蓿草地、柠条灌丛、山杏林以及油松林）为研究对象,通过测定0-20 cm、20-40 cm和40-60 cm土壤水稳性团聚体,分析土壤团聚体组成、稳定性及抗侵蚀能力特征。结果表明：1）不同恢复方式不同植被类型间土壤水稳性团聚体稳定性差异显著（P<0.05）,自然恢复方式的土壤水稳性团聚体平均重量直径显著高于天然荒草和人工恢复方式,且7种植被类型土壤大团聚体质量百分比均在67.97%-90.12%之间;人工恢复方式土壤水稳性团聚体稳定性较差,其中油松林稳定性最差。2）土壤团聚体破坏率和土壤抗侵蚀能力均表现出自然恢复方式更有利于土壤结构稳定性的提高。3）土壤水稳性大团聚体含量越高,土壤团聚体越稳定,土壤结构稳定性就越好;平均重量直径与土壤可蚀性因子K值呈极显著性负相关（P<0.01）。本研究结果表明自然恢复方式能够显著提高土壤团聚体的稳定性,从而提升土壤的抗侵蚀能力,建议当地在未来植被恢复规划中采取自然恢复方式更有利于生态恢复的有效进行。     

Detection of heavy metal ion resistance genes in Gram-positive and Gram-negative bacteria isolated from a lead-contaminated site

Resistance to a range of heavy metal ions wasdetermined for lead-resistant and other bacteria whichhad been isolated from a battery-manufacturing sitecontaminated with high concentrations of lead. Several Gram-positive (belonging to the genera Arthrobacter and Corynebacterium) andGram-negative (Alcaligenes species) isolateswere resistant to lead, mercury, cadmium, cobalt,zinc and copper, although the levels of resistance tothe different metal ions were specific for eachisolate. Polymerase chain reaction, DNA-DNAhybridization and DNA sequencing were used to explorethe nature of genetic systems responsible for themetal resistance in eight of the isolates. SpecificDNA sequences could be amplified from the genomic DNAof all the isolates using primers for sections of themer (mercury resistance determinant on thetransposon Tn501) and pco (copperresistance determinant on the plasmid pRJ1004) geneticsystems. Positive hybridizations with mer andpco probes indicated that the amplified segmentswere highly homologous to these genes. Some of thePCR products were cloned and partially sequenced, andthe regions sequenced were highly homologous to theappropriate regions of the mer and pcodeterminants. These results demonstrate the widedistribution of mercury and copper resistance genes inboth Gram-positive and Gram-negative isolates obtainedfrom this lead-contaminated soil. In contrast, theczc (cobalt, zinc and cadmium resistance) andchr (chromate resistance) genes could not beamplified from DNAs of some isolates, indicating thelimited contribution, if any, of these genetic systemsto the metal ion resistance of these isolates.     

香根草对土壤中几种重金属离子富集能力的比较研究

用组织培养的香根草无菌苗作为试验材料,进行香根草对Cd、Cr、Pb和Ni四种重金属离子的富集能力比较试验,分别测定了香根草体内的重金属含量、香根草与重金属元素的相关性、香根草对重金属的富集系数和根系滞留率.结果表明：香根草对四种重金属离子都具有较高的富集能力.其中,香根草植物体中元素总含量表现为Ni＞Cr＞Pb＞Cd,在茎叶和根中的分含量,均表现为根＞茎叶;香根草与重金属元素的关系中,Cd的相关性最显著;富集系数与重金属浓度呈负相关,以Ni最为明显;从滞留率的角度来看,以Cr在香根草根系的滞留率最大,但对同一种重金属来说,随浓度的变化,香根草根系对它的滞留率却几乎是恒定的.     

东北高寒地区土壤动物和微生物的生态特征研究

东北高寒地区农田在作物生长期内土壤动物具有明显的季节特征。土壤微生物季节变化具有单一的峰值,其中细菌和放线菌的高峰值在7月份,真菌的高峰值在6月份,从土壤酶及理化性质对土壤动物和微生物影响的灰色分析表明,对土壤动物和微生物影响最大的是脲酶,pH值,含水量和速效磷,并建立了8个灰色数学模型[GM(0,5)],最小的为土壤水解氮,这表明了土壤中水和速效磷是该地区土壤生态稳定的主要因素,因此调整土壤水分供应状况和土壤磷肥输入对改善土壤质量和作物生产将是一个重要的策略,同时加强对脲酶对土壤氮素状况等相关因素的分析。     

Analysis of rhizobacterial communities in perennial Graminaceae from polluted water meadow soil, and screening of metal-resistant, potentially plant growth-promoting bacteria

This study investigates the impact of long-term heavy metal contamination on the culturable, heterotrophic, functional and genetic diversity of rhizobacterial communities of perennial grasses in water meadow soil. The culturable heterotrophic diversity was investigated by colony appearance on solid LB medium. Genetic diversity was measured as bands in denaturing gradient gel electrophoresis (DGGE) obtained directly from rhizosphere soil and rhizoplane DNA extracts, and from the corresponding culturable communities. In the two rhizospheric fractions the DGGE profiles of the direct DNA extracts were similar and stable among replicates, whereas in the enriched cultures the profiles of the fractions differed, but among the replicates they were similar. One hundred isolates were collected into 33 different operational taxonomic units by use of amplified internal transcribed spacers and into 19 heavy metal-resistant phenotypes. The phylogenetic position of strains belonging to 18 operational taxonomic units, representing more than 80% of the isolates, was determined by 16S rRNA gene sequencing. Several heavy metal-resistant strains were isolated from rhizoplane. Finally, metal-resistant rhizobacteria were tested for plant growth-promoting characteristics; some were found to contain 1-aminocyclopropane-1-carboxylic acid deaminase and/or to produce indole acetic acid and siderophores. Two strains resistant to cadmium and zinc, Pseudomonas tolaasii RP23 and Pseudomonas fluorescens RS9, had all three plant growth-promoting characteristics. Our findings suggest that bacteria can respond to soil metal contamination, and the described methodological approach appears promising for targeting potential plant growth-promoting rhizobacteria.     

Seasonal fluctuations in the population of denitrifying and N2-fixing bacteria in an acid soil of a Norway spruce forest

The seasonal fluctuations in the concentration of cultured denitrifying and N₂-fixing bacteria were followed in an ammonium fertilised and a control soil of a Norway spruce forest near Villingen/Black Forest from December 1994 to August 1998. The horizontal distribution of bacteria in three layers was determined by the MPN-method and by molecular probing (colony hybridisation) using specific 0.4–0.7 kb DNA probes for denitrification steps (narG, nirS, nirK and nosZ) and for N₂-fixation (nifH). The data showed that highest bacterial counts and higher numbers of denitrifying and N₂-fixing bacteria were generally detectable in the upper (= 5 cm) soil layer and that their amount decreased with soil depth. The concentration of these cultured bacteria showed seasonal fluctuations with highest numbers in autumn/winter/early spring and with low counts in summer. Denitrifying and N₂-fixing bacteria amounted to less than 10% of the total number of cultured bacteria determined by the MPN-method. Fertilisation with ammonium did not cause a shift in the population of these bacteria. These findings were corroborated by hybridisation experiments with genomic DNA isolated from the different layers. Strongest DNA–DNA hybridisation band intensities were obtained in the upper soil layer and their intensities decreased with soil depth. Soil samples from Villingen assayed in the laboratory produced N₂O (in dependence of nitrate and C₂H₂ added to the vessels) and utilised this gas with higher activities in the assays with the fertilised soil. It is concluded that molecular techniques can successfully be applied for assessing seasonal fluctuations of bacterial populations in soil. Relative abundance of denitrifying and N₂-fixing bacteria can be determined from experiments with DNA isolated from soils. Attempts to transform these results to the total population of soil bacteria on a single cell basis are faced with many uncertainties.     

Fractionation of heavy metals in contaminated soils surrounding non-ferrous metals smelting area in the North China Plain

Abstract

The accumulation of heavy metals in soil is a serious environmental problem. The risk of metals in soil is associated critically with their species. Operationally determined speciation analysis of Cr, Mn, Ni, Cu, Zn, Sb, Cd and Pb was carried out in the area of non-ferrous metals-smelting in the North China Plain, using inductively coupled plasma-mass spectroscopy after sequential chemical extraction. The average potential mobility fraction was calculated. The average potential mobility of the metals had the following order: Cd(44.7%) > Pb(29.6%) > Mn(14.8%) > Zn(12.5%) > Cu(5.9%) > Sb(5.0%) > Ni(2.1%) > Cr(0.8%). It is concluded that there is a distinct spatial heterogeneity in the concentration of heavy metals in the studied area. The results indicate that the polluting heavy metals, in particular Cd and Pb, have high potential mobility.     

Pollution and health risk assessment of heavy metals in urban soil in China

The pollution and potential health risk due to lifetime exposure to heavy metals in urban soil of China were evaluated, based on the urban soil samples collected from published papers from 2005 to 2014. The contamination levels were in the order of Cd > Hg > Cu > Zn > Pb >As > Ni > Cr, and Hg and Cd fell into the category of “moderately contaminated” to “heavily contaminated.” The non-carcinogenic risk for different populations varied greatly, among which children faced high risk, and then the adult female and adult male followed. The hazard index (non-carcinogenic risk) higher than 1.00 occurred in Shanghai, Gansu, Qinghai, Hunan, and Anhui, whereas most of those in northern and western China had low risks. For the carcinogenic risk, Anhui and Ningxia provinces had urban soils exceeding the safe reference (1 × 10^?6–1 × 10^?4). Qinghai and Gansu had high carcinogenic risks since their risk indexes were much closer to the reference, and the others were in low risk.     

重金属超富集植物及植物修复技术研究进展

植物修复技术（Phytoremediation)是近年来发展起来的一种主要用于清除土壤重金属污染的绿色生态技术,重金属超富集植物（hyperaccumulator)及植物修复技术是当前学术界研究的热点领域,目前虽已有Cd、Co、Cr、Cu、Mn、Ni、Pb、Zn等超富集植物发现的报道,但尚无一例报道来自于中国,中国具有广袤的国土面积、丰富的植物类型和多种（处）古老的矿山开采与冶炼场所,在中国开展超富集植物的寻找,研究与开发工作,将会有重要突破,并具有重要的理论与实践意义,本文拟就国内外在这一领域的研究进展作一简要综述。     

生物质炭添加对红壤性水稻土重金属有效性及土壤质量的影响

通过田间定位试验探讨了不同生物质炭添加量对红壤性水稻土理化性质、重金属有效性和土壤质量的影响。生物质炭于2017年水稻种植前一次性添加于耕作层(0～17cm),分别设置5个不同处理:CK:0 t·hm^-2,A10:10 t·hm^-2,A20:20 t·hm^-2,A30:30t·hm^-2和A40:40 t·hm^-2,经种植两季水稻后于2018年9月采集耕作层(0～17 cm)和犁底层(17～29 cm)土壤,计算土壤质量指数(SQI),评价土壤质量。结果表明:在耕作层(0～17 cm)和犁底层(17～29 cm),随着生物质炭添加量的增加,土壤容重逐渐降低;土壤孔隙度、pH值、有机质和可溶性有机碳含量增加,铵态氮和有效磷分别在添加量为20和30 t·hm^-2时达到最大值;土壤中脲酶、过氧化氢酶和蔗糖酶的活性降低;生物质炭能够降低有效态Cd、As和Pb的含量,在生物质炭添加量为40 t·hm^-2时最低;在土壤耕作层(0～17cm),有效态...     

黄河滩地和稻田土中铁还原菌、不产氧光合细菌分布机制

【目的】探讨沿黄流域土壤中铁还原菌(ferric reducing bacteria, Fe RB)、不产氧光合细菌(anoxygenic phototrophic bacteria, An PB)的分布机制。【方法】以沿黄流域(原阳段)为研究对象,采集黄河滩地和稻田土样,利用16Sr RNA基因高通量测序和实时荧光定量分析技术,结合统计学分析,揭示Fe RB、An PB菌群结构、丰度和主要环境影响因子。【结果】二者中的优势Fe RB在科(属)水平为Hydrogenophilaceae(Thiobacillus)、 Bacillaceae(Bacillus)、 Clostridiaceae、Rhodobactereace(Rhodobacter)、 Geobacteraceae(Geobacter),优势An PB为Rhodobactereace(Rhodobacter)、 Chloroflexaceae(Chloronema)、 Acetobacteraceae(Roseomonas)。An PB中Rhodobacteraceae与Fe RB中Bacillaceae、 Clostri...