蒙古沙冬青AM真菌物种多样性与土壤因子的相关性

为了探明蒙古沙冬青(Ammopiptanthus mongolicus)根围AM真菌物种多样性年际变化规律以及土壤因子的生态功能,于2012年7月和2013年7月从宁夏银川、沙坡头和甘肃民勤3个样地分别从O～10,10～20,20～30,30～40,40～50 cm 5个土层对沙冬青根围土样进行采集,共分离鉴定出AM真菌5属36种,其中,球囊霉属Glomus 16种,无梗囊霉属Acaulospora 13种,管柄囊霉属Funneliformis 3种,盾巨孢囊霉属Scutellospora 3种,多孢囊霉属Diversispora 1种.不同样地和土壤深度,AM真菌种类组成、孢子密度和种丰度在年际间均有明显差异.相关性分析表明,孢子密度与土壤酸性磷酸酶和总球囊霉素显著正相关;种丰度与土壤脲酶、有机质和碱解氮显著正相关.主成分分析表明,土壤有机质、碱解氮、速效磷、速效钾、脲酶、碱性磷酸酶是影响AM真菌物种多样性的主要因子.研究结果说明,AM真菌物种多样性及其分布规律可以用作检测和评价荒漠环境土壤状况的生态指标.     

内蒙古农牧交错区沙蒿根围AM真菌物种多样性

2009年4月、7月和10月分别在内蒙古农牧交错区元上都、黑城子和大河乡样地采集沙蒿(Artemisia sphaerocephala)根围土壤样品,利用形态学和微形态学特征分离鉴定沙蒿根围AM真菌种类,研究了AM真菌物种多样性.共分离鉴定出AM真菌3属20种,其中盾巨孢囊霉属(Scutellospora)2种,无梗囊霉属(Acaulospora)4种,球囊霉属(Glomus)14种.3属AM真菌在3个样地均有分布.3个样地共同优势种是黑球囊霉(G.melanosporum)和网状球囊霉(G.reticulatum).AM真菌物种丰度、香浓-威纳指数和均匀度在时间上表现为4月<7月<10月,空间上表现为元上都<黑城子<大河乡.扫描电镜下不同属种孢子表面纹饰特征差异明显,可作为AM真菌分类的参考依据.     

毛乌素沙地沙柳根际AM真菌资源和空间分布

2006年10月,从毛乌素沙地4个自然生境下沙柳(Salix psammophila)根际0～10,10～20,20～30,30～40和40～50 cm 5个土层分别采集土壤样品,研究了沙柳根际AM真茵种类和空间分布.结果表明,在分离的4属12种AM真菌中,摩西球囊霉(Glomus mosseae)和缩球囊霉(Glomus constrictum)是优势种.AM真菌分布和定殖与样地生态条件和采样深度密切相关,易误巨孢囊霉(Gigaspora decipiens)只出现在米脂样地,网状球囊霉(Glomus reticulatum)等只出现在东胜样地,双网无梗囊霉(Acaulospora direticulatum)和黄色盾巨孢囊霉(Scutellospora armeniaca)只出现在榆林样地,卷曲球囊霉(Glomus convolutum)只出现在伊金霍洛旗中科院研究站样地.AM真菌孢子密度和总定殖率最大值都出现在东胜样地,孢子密度和菌丝、菌丝套定殖率的最大值都出现在0～20 cm土层.AM真菌孢子密度与土壤温度和速效P呈极显著正相关,泡囊定殖率与土壤温度和速效P呈极显著正相关,与土壤有机质呈显著负相关;丛枝定殖率与速效P呈极显著正相关;总定殖率与速效P呈正相关.可见,沙柳根际AM真菌分布和定殖具有明显的空间并质性,且与土壤速效P等土壤因子关系密切.     

用模糊聚类分析法对VA菌根真菌进化关系的初步探讨

选取１５个形态学特征,用模糊聚类分析法对ＶＡ菌根真菌的进化进行了初步研究,结果发现：ＶＡ菌根真菌的６个属可以聚为两大类群,无梗孢囊霉属（Ａｃａｕｌｏｓｐｏｒａ）和内养囊霉属（Ｅｎｔｒｏｐｈｏｓｐｏｒａ）是分化较早,两者平行进化的一个类群;球囊霉属（Ｇｌｏｍｕｓ）,硬囊霉属（Ｓｃｌｅｒｏｃｙｓｔｉｓ）,巨孢囊霉属（Ｇｉｇａｓｐｏｒａ）和盾巨孢囊霉属（Ｓｃｕｔｅｌｏｓｐｏｒａ）是起源于一个象球囊霉（Ｇｌｏｍｕｓｌｉｋｅ）的共同祖先的另一个类群,在这个类群中,球囊霉属与硬囊霉属之间的分化较晚,亲缘关系较近,巨囊霉属和盾巨孢囊霉属是平行进化的     

道地药材白芷根际AM真菌的生态学

2006年10月在河北省安国市的4个样地,从0~10、10~20、20~30和30~40 cm 4个土层采集白芷根际土样,系统研究白芷根际AM真菌空间分布和土壤因子之间的相关性.结果表明,白芷能与AM真菌形成良好的共生关系.白芷具有Paris型菌根.AM真菌不同结构定殖率和孢子密度与样地生态条件密切相关.AM真菌不同结构定殖率在齐村最高,孢子密度在郭北庄最高,采样深度对孢子密度和AM真菌定殖率有显著影响,在10~20 cm或20~30 cm土层出现最大孢子密度;AM真菌定殖率在0~10 cm或20~30 cm土层有最大值.总定殖率与土壤有机质呈显著正相关,孢子密度与土壤速效N呈显著正相关,土壤pH与AM真菌泡囊定殖率呈显著负相关.菌根定殖率与孢子密度之间没有显著相关性.土样中AM真菌有球囊霉属(Glomus)、无梗囊霉属(Acaulospora)和盾巨孢囊霉属(Scutellospora).     

野生油茶根围土壤的AM真菌多样性调查

为探明野生油茶根围土壤AM真菌的种类组成与多样性。对野生油茶根围土壤AM真菌进行分离与形态学鉴定,同时提取土壤DNA,进行高通量测序,通过形态学鉴定出3属6种AM真菌,分别为台湾硬囊霉、悬钩子硬囊霉、黄孢球囊霉、长孢球囊霉、蜜色无梗囊霉和柯氏无梗囊霉;通过高通量测序鉴定出球囊霉属、原囊霉属、近明囊霉属等6属42种AM真菌,其中有36个VT种; VTX00166和球囊霉属分别为野生油茶根围土壤AM真菌的优势种和优势属;与形态学鉴定相比,高通量测序能检测出更多的AM真菌种类。     

葛藤(Puerraria lobata)根际AM真菌生态学研究

2004年7月至12月每月中旬分别从0~10,10~20,20~30和30~40 cm土层采集根际土样,对陕西武功县葛藤根际AM真菌进行了系统的生态学研究.结果表明,AM真菌的分布和定殖与时间变化密切相关,菌根真菌的最高定殖率伴随有最大的孢子密度,最高值都出现在2004年11月.土壤pH值与泡囊定殖率呈极显著负相关.孢子密度与泡囊定殖率呈显著正相关,速效磷与泡囊定殖率呈显著负相关;碱解氮与孢子密度、总定殖率、泡囊、菌丝定殖率呈极显著负相关.在检测和评估土壤生态状况和植物形成菌根能力等方面,AM真菌孢子密度和不同结构定殖程度是十分有用的指标,尤其是泡囊定殖率可作为葛藤优化盐碱地状况的重要指标.土样中AM真菌多为球囊霉属(Glomus)种类,也有少数无梗囊霉属(Acaulospora)和盾巨孢囊霉属(Scutellospora)的种类.     

云南轿子山腋花杜鹃菌根多样性研究

以云南轿子山野生的腋花杜鹃为研究对象,利用石蜡切片、根系透明染色,观察腋花杜鹃菌根的解剖结构,检测菌根的侵染率及研究根系共生菌根真菌的形态多样性;采用形态鉴定的方法研究根际土壤AM真菌的物种多样性;采取形态学结合rDNA ITS序列测序方法,研究杜鹃植物根系共生真菌的物种多样性。结果表明:轿子山腋花杜鹃的菌根真菌具有3种类型:杜鹃花类菌根真菌(ERM)、丛枝菌根(AM)真菌及暗色有隔内生真菌(DSE);菌根侵染率与AMF孢子密度之间的相关性是0.884,呈显著的正相关关系;其中从土壤样品中分离鉴定出4属5种AMF孢子,分别为瑞氏无梗囊霉(Acaulospora rehmii),大巨孢囊霉(Gigaspora gigantea),布氏球囊霉(Glomus brohultii)和沙生球囊霉(Glomus arenarium),美丽盾巨孢囊霉(Scutellospora calospora);从腋花杜鹃中共分离出1株与杜鹃花类菌根真菌Cryptosporiopsis ericae,1株与根相关的真菌,2株菌根真菌共生真菌Dreschlera sp.,Periconia sp..     

河北峰峰矿区构树AM真菌物种多样性及生态适应性

为探究河北峰峰矿区构树(Broussonetia papyrifera)arbuscular mycorrhizal(AM)真菌物种多样性及其对污染环境的生态适应性,2016年10月从峰峰矿区义井镇、界城镇与峰峰镇样地采集构树根围0～20 cm和20～40 cm土层土壤样品,系统研究AM真菌种质资源、生态分布以及与土壤因子的相关性.共分离鉴定AM真菌8属43种,其中无梗囊霉属(Acaulospora)和球囊霉属(Glomus)为广谱生态型属,网状球囊霉(G.reticulatum)、稀有内养囊霉(Entrophospora infrequens)、凹坑球囊霉(G.multiforum)为广谱生态型种.义井镇AM真菌香农-威纳指数、均匀度和种丰度最高,界城镇最低.峰峰矿区重金属镉和锌含量超标.相关性分析可知,孢子密度与总球囊霉素极显著正相关,与土壤碱解氮显著正相关,与镉含量显著负相关,土壤总球囊霉素与有机碳显著正相关,与镉含量显著负相关.峰峰矿区构树部分地区部分AM真菌孢子具有颜色深、表面网纹间隔致密等生态适应性特征,有利于AM真菌在污染土壤中分布和活动.     

不同AM真菌对玉米生长的促生效应

在盆栽条件下对玉米接种5种不同AM真菌:地表球囊霉、光壁无梗囊霉、单孢球囊霉、根内球囊霉以及土著AM真菌,研究不同AM真菌对玉米的促生效应.结果显示不同AM真菌均能够成功侵染玉米根系,但对玉米生长的促生作用存在差异,除了单孢球囊霉外的4种AM菌剂均对玉米地上部分的生长产生显著的促进效应.对玉米地下生物量而言,只有土著AM真菌具有显著的促进效应,所有AM真菌菌剂均没有显著增加玉米的根长.从综合效应而言,根内球囊霉促生效应最显著,单孢球囊霉对玉米没有显著的促生效应.结果表明不同AM真菌对同一宿主植物促生效应不同,只有选择合适的AM真菌才能产生最佳的效果.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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