河南省HIV21 新近感染者耐药基因研究

目的　了解河南省艾滋病病毒Ⅰ型( HIV21) 新近感染者的耐药情况。方法　2006 年8 月- 2007 年6 月,在河南省艾滋病自愿咨询(VCT) 检测点发现的未进行抗病毒治疗的HIV21 感染者,以酶联免疫吸附试验初筛、 蛋白印迹试验确认HIV21 感染,BED2CEIA 方法检测新近感染。检出的新近感染样品进行基因型耐药检测,提取 血浆中RNA ,套式聚合酶链反应(Nested2PCR) 扩增HIV21 pol 基因区,PCR 产物双脱氧法测序,所得序列与Los Alamos HIV 标准株序列比对,构建系统进化树分析亚型;利用Stanford HIVdb Drug Resistance Database 分析耐 药相关突变(DRM) 和耐药情况。结果　共检出HIV21 新近感染39 例,扩增测序有34 例新近感染样品分析成功。 亚型分析结果为B′亚型32 例(9411 %) ,CRF01_AE 重组亚型1 例(219 %) ,C 亚型1 例(219 %) 。未发现蛋白酶抑 制剂( PI) 主要DRM ,检测到10 例(2914 %) 存在PI 次要DRM;未发现核苷类逆转录酶抑制剂(NRTI) 的DRM;3 例(818 %) 存在非核苷类逆转录酶抑制剂(NNRTI) 的DRM。耐药分析显示,有2 例(519 %) 对NNRTI 类药物耐 药。结论　目前河南省HIV21 新近感染人群中耐药状况处于中等水平,有必要加强HIV21 的耐药监测。

西黑冠长臂猿（Nomascus concolor）栖息地与鸣叫特征分析

本研究重点对云南哀牢山、无量山、永德大雪山以及老挝 Nam Kan 保护区西黑冠 长臂猿(Nomascus concolor)的鸣叫特征进行了分析研究，以探讨长臂猿鸣叫个体特异性 的发生机制及其在地理种群区分或亚种地位划分中的意义；同时对哀牢山平河西黑冠长 臂猿栖息地乔木结构进行了样方调查，揭示西黑冠长臂猿高海拔栖息地的乔木结构特 征，为后续行为学研究提供基础生态数据。 研究表明，云南省哀牢山平河（N 24°20′09.5″, E 101°17′16.1″, 海拔2600m）的黑 长臂猿栖息地有乔木57 种隶属于23 科37 个属；木质藤本植物9 种隶属于6 科8 属。 优势科主要为杜鹃花科（Ericaceae）、木兰科（Magnoliaceae）、山茶科（Theaceae）和 壳斗科（Fagaceae）植物。乔木的多样性指数、均匀度指数在沟底明显降低，而乔木1 层和2 层所占的比例以及木质藤本的平均多度均随着坡位的下降而升高。与其他地区的 长臂猿相比，哀牢山黑长臂猿的活动高度较低（10—22m），果实性食物种类较少。 西黑冠长臂猿的雄性鸣叫包括Boom 音节、aa 音节、弱调节音节、强调节音节和 coda 音节，Boom 音节只是一单独的条带状音节，结构最简单也最稳定；aa 音节、弱调 节音节、强调节音节和coda 音节的稳定性则呈现出依次增大的趋势。强调节音节和coda 部分的稳定性在总体没有显著差异，但在某些变量上coda 音节比强调节音节有显著更 高的稳定性。在此基础上，重点基于对coda 音节的分析，发现同一地点不同群体的雄 性西黑冠长臂猿个体之间存在非常显著的鸣叫特异性，并且同一地点不同群体的雄性个 体之间鸣叫的差异，显著高于不同地点间雄性个体间鸣叫的差异。这一发现表明西黑冠 长臂猿很有可能在有意识地通过鸣叫声音的调节，来增加与邻近群体间鸣叫的差异性， 并依靠这一行为识别邻近群的成年个体和陌生个体或新成年的未配对个体，这对具领域 性、配对的长臂猿来说具有显著的生态适应意义。基于对西黑冠长臂猿所有4 个亚种雌 雄个体鸣叫的逐步判别分析，结果表明西黑冠长臂猿明显分为3 个类群：1) 指名亚种 （N. c. concolor）和景东亚种（N. c. jingdongensis）为同一类群；2)滇西亚种（N. c. furvogaster）类群；3)老挝亚种（N. c. lu）类群，综合我们及前人的研究结果，我们认 为老挝亚种与其它三个亚种之间很可能已经达到了亚种分化的水平，滇西亚种也是如 此，但其有效性还值得进一步研究和探讨，而指名亚种和景东亚种间可能还没有达到亚种分化的水平。

YidC/Oxa/Alb3超家族蛋白的起源演化研究

YidC/Oxa/Alb3超家族蛋白是重要的蛋白转运酶，分别负责将一些能量合成相关的蛋白质转运到细菌内膜、线粒体内膜和叶绿体类囊体膜。因为线粒体和叶绿体起源于内共生的细菌，所以真核细胞线粒体的Oxa和叶绿体的Alb3很容易像许多其它线粒体/叶绿体蛋白质一样被认为是起源于内共生细菌的同源物YidC。事实是否如此？我们基于已有的基因组数据库，对整个生物界中的众多古菌、真细菌和真核生物中YidC/Oxa/Alb3超家族的分布和分子系统发育关系进行了较全面、系统的调查分析，获得了如下主要结果： 1）YidC在古细菌中有所发现，但只零星分布于一些广古菌（Euryarchaeota）中；2）绝大多数真细菌只有一个YidC基因，但一些革兰氏阳性菌（芽胞杆菌、乳酸杆菌、放线菌和梭菌中的一些物种）已分化出两个YidC基因；3) 分子系统分析显示：线粒体Oxa、叶绿体Alb3和古菌YidC组成了3个独立的进化分枝，线粒体Oxa并未与蛋白菌序列聚在一起，叶绿体Alb3也未显示出与蓝细菌YidC有更近的亲缘关系；4）真菌、后生动物、绿藻和植物均具有两个Oxa（Oxa1和Oxa2）基因，这些真核生物的Oxa序列聚在两个独立的分开的进化枝上(Oxa1和Oxa2)；绿藻和植物中普遍具有两个Alb3基因。绿藻类生物的Alb3分布在两个独立的进化枝上，标记为Alb3.1和Alb3.2。植物Alb3序列也分布在两个不同的进化枝（Alb3.a和Alb3.b）上，并且它们一起和绿藻Alb3.1进化枝距离最近；结构域分析显示绿藻和植物中的Oxa2具有一个额外的C端TPR结构域；一些原生生物中Oxa和Alb3同源物的数目和在进化树上的聚类情况很特殊。 根据以上结果，我们认为：YidC亚家族蛋白在真细菌和一些广古菌中已起源；真核生物Oxa和Alb3基因有不同的原核起源，但它们的起源跟这两个细胞器的内共生起源事件无关；Oxa基因和Alb3基因在真核细胞进化早期即分别发生了古老的重复事件，因此现在绝大多数真核生物中均有两个Oxa和两个Alb3基因。但是后来在一些类群中，尤其是原生生物中，Oxa和Alb3基因发生了次生性丢失、新的复制或获得新的结构域编码片段，从而导致这些类群中这两种转运酶有丰富的多样性和不同的适应性。 最终，基于以上结果和结论，我们勾勒出了YidC/Oxa/Alb3超家族在整个生 I 物界中的进化路线图。

Photoluminescence studies of GaAs/AlGaAs single quantum well intermixed by Ga+ ion implantation

Ga(+)ion implantation followed by rapid thermal annealing (RTA) was used to enhance the interdiffusion in GaAs/AlGaAs single Quantum Wells(SQWs). The extent of intermixing was found to be dependent on the well depth, number of implanted ions and annealing time. A very fast interdiffusion process occurs at the initial annealing stage. After that, the enhanced diffusion coefficient goes back to the umimplanted value. We propose a two-step model to explain the diffusion process as a function of the annealing time : a fast diffusion process and a saturated diffusion process. The interdiffusion coefficient of the fast diffusion was found to be of well depth dependence and estimated to be in the range of 5.4x10(-16) similar to 1.5x10(-15)cm(2)s(-1). Copyright (C) 1996 Published by Elsevier Science Ltd

立方氮化硼薄膜制备与性质研究新进展

立方氮化硼（c-BN）具有优异的物理和化学性质,在力学、光学和电子学等方面有着广泛的应用前景.自上世纪80年代开始,低压沉积c-BN薄膜的研究迅速发展,到90年代中期达到高潮,随后进展缓慢,c-BN薄膜研究转入低潮.近年来,c-BN薄膜研究在几方面取得了突破,如获得与衬底粘附良好、厚度超过1μm的c-BN厚膜;成功实现了c-BN单晶薄膜的异质外延生长;此外,在c-BN薄膜力学性质和过渡层微结构研究方面也取得了进展.本文主要评述最近几年c-BN薄膜研究在以上几方面取得的最新进展.

GeSi/Si多层异质外延载流子浓度的分布

通过实验研究了一种与Ge_xSi_(1-x)合金表面具有良好电化学界面的电解液，利用电化学C-V方法研究了多层Ge_xSi_(1-x)/Si异质外延材料的载流子浓度纵向分布。实验结果表明

杉木人工林凋落物对土壤碳平衡的影响

土壤碳循环过程是目前全球碳源碳汇研究的核心，目前对土壤碳循环过程和机制的研究还十分缺乏。杉木人工林约占我国人工林面积的1/4，由于近几十年经营管理措施不当，土壤有机碳的下降已经成为不争的事实，极大地影响了杉木人工林生产力的可持续发展。本研究通过对杉木人工林土壤有机碳来源、分解和释放动态的区分量化，结合13C标记示踪试验，开展了杉木凋落物分解对土壤有机碳平衡影响的研究，为土壤碳平衡和转化机理及杉木人工林的可持续经营提供了可靠的理论依据。通过系统的研究，得出以下结论： ⑴估算了典型杉木人工林土壤碳的周转状况，研究发现典型杉木人工林土壤碳更新较慢。土壤碳年输入量、形成量、转化量、输出量和贮存量分别为2.79 t hm-2、1.58 t hm-2、2.04 t hm-2、4.57 t hm-2、113.21 t hm-2。其中在土壤碳年排放量中矿质土层呼吸、根呼吸、凋落物层呼吸碳分别占土壤碳总排放量的50.6%、26.0%、23.1%。 ⑵计算了凋落物分解对土壤碳平衡的贡献。不同器官凋落物在土壤中的矿化释放碳量和进入土壤碳库量均随着凋落物易分解性的增大而增大，并且各器官凋落物分解以CO2-C释放最多，以微生物量碳存在的量次之，以可溶性碳存在的量最少。年均温16.5 ℃条件下培养100天，分别来自于叶、枝、细根、粗根有机碳的13.81%、9.26%、5.74%、4.62%被矿化释放，占总CO2-C释放量的比例分别为43.7%、37.2%、31.9%、29.0%。同时不同器官凋落物依次有3.05%、3.26%、2.24%、1.84%存在于土壤微生物碳库，占总微生物量碳的比例分别为12.9%、14.3%、10.5%、8.8%；不同器官凋落物依次有0.62%、0.62%、0.31%、0.24%存在于可溶性有机碳库，占总可溶性有机碳的比例分别为3.99%、4.10%、2.13%、1.73%。 ⑶不同器官凋落物进入土壤对土壤碳排放的激发效应不同，叶、枝、细根、粗根加入土壤产生了正激发效应，激发率依次为6.6%、7.0%、2.2%、2.8%。并且土壤风干－湿润过程影响了凋落物在土壤中的分解和转化过程。土壤风干－湿润使起始矿化底物库增大，培养初期凋落物分解速率上升，同时土壤原有机碳矿化速率降低，微生物对凋落物碳的利用以及凋落物对可溶性有机碳的贡献下降。 ⑷凋落物碳在不同轻组密度组分中的分布不同，但各器官凋落物间无明显差异，均为中等密度自由轻组最多，其次为最小密度自由轻组，最少为闭蓄轻组。室外培养224天，结果表明叶、枝、细根、粗根凋落物在各密度组分中的分配情况为：<1.0 g cm-3自由轻组中16.5~19.1%，1.0~1.8 g cm-3自由轻组中56.8~65.2%，闭蓄轻组中残留5.7~6.9%，其余的9.9～21.0%被矿化损失。研究还表明，凋落物粉碎添加方式能改变其在土壤组分中的分布比例，倾向于向较重的密度组分中分布而被保护起来利于有机碳的积累。

硝化抑制剂在我国棕壤和红壤上的应用效果研究

土壤类型、温度等条件是影响硝化抑制剂效果的重要因素，为了探讨几种国外报道的高效硝化抑制剂在我国棕壤和红壤上的适应情况，以及温度等条件对于施肥土壤中NO3--N的积累和硝化抑制剂效果的影响，进行了本研究。采用室内培养的方式，研究了ATC、DMPP和CMP（每种抑制剂在两种土壤上分别设两个浓度处理）在我国棕壤和红壤上的效果，与目前应用较多的DCD（0.5%、1.0%两个浓度处理）进行效果对比；研究了温度条件、添加C源及培养条件对土壤中NO3--N积累及CMP硝化抑制效果的影响。结果表明，土壤条件是影响NO3--N积累和所用四种硝化抑制剂（DMPP、CMP、ATC、DCD）抑制效果的一个显著因素，棕壤中氮素转化较快，硝化抑制剂表现出效果较早，在红壤中起效时间较晚，在两种土壤条件下，所用抑制剂都表现出了良好的效果，在60天内ATC、CMP和DMPP的效果与10倍用量的DCD效果类似，甚至好于DCD，在棕壤中同种抑制剂的两个浓度处理之间存在显著差异，但是在红壤几个处理之间没有表现出显著差异；温度条件也是影响NO3--N积累的一个显著因素，从计算硝化抑制率看出，在25℃和30℃下CMP表现出了高效，37℃下抑制率下降，效果变差；添加两个浓度的葡萄糖对于对照中NO3--N的积累以及硝化抑制剂的硝化抑制效果没有表现出显著作用；增加的一步预培养恢复了土壤中微生物的活性在短期内体现了出来，但是长期看对于NO3--N积累量、变化趋势以及硝化抑制率都没有表现出显著作用。

高浓度CO_2下红松和长白赤松土壤微生物活性研究

大气CO_2浓度升高已经成为全球生态坏境研究中的热点，木文主要研究了长白赤松和红松根际及非根际土壤微生物数量、生物量C、土壤酶活性以及根际／非根际细菌群落结构对高浓度CO_2的响应规律，得出的主要研究结论如下：（1）高浓度CO_2对红松和氏白赤松根际及非根际土壤细菌数量影响显著，而对真菌和放线菌数量的影响却不明显；（2）700μmol·mol~(-1) CO_2对红松和长白赤松土壤微生物生物量碳的影响较500μmolmol~(-1)CO_2显著，且主要表现为抑制效应；（3）对红松土壤酶活性来说，高浓度CO_2对蛋白酶、服酶、磷酸酶、过氧化氢酶、多酚氧化酶以及脱氢酶活性主要表现出了促进作用，而对淀粉酶和转化酶的活性主要是抑制作用；对长白赤松说，高浓度CO_2对脉酶、转化酶、淀粉酶、过氧化氢酶、多酚氧化酶以及脱氢酶活性主要表现出了显著的促进作用，而对蛋白酶和磷酸酶的活性却主要起着抑制作用。此外，土壤酶活性的月动态规律在不同程度上也受到了高浓度CO_2的影响；（4）红松和长白赤松土壤酶活性之间、土壤酶活性与微生物生物量C以及微生物数量之间的相关性受到了高浓度CO_2的影响，但不同浓度CO_2其影响规律也不同：（5）不同树种其土壤酶活性、微生物数量以及微生物生物量C对高浓度CO_2的响应规律不同，即土壤生化活性与所研究的树种有关；（6）大气CO_2浓度升高对红松和长白赤松根际和非根际土壤细菌群落结构产生了较大的影响，主要表现为部分新的物种的出现／或原有物种数量的丰富以及原有物种的消失或数量被削弱，但主要建群种却未发生改变，此外，细菌群落结构在700μmol·mol~(-1) CO_2条件和500μmol·mol~(-1) CO_2下的变化规律亦不同。

不同处理方式采伐剩余物的分解及其对森林更新的影响

采伐迹地上运走大径级的原木所剩下的枝桠物质是生态系统养分能量的来源；是动力，植物和微生物物栖息地。在本世纪五十年代就有人（A. A. Loman）对择伐和皆伐迹地上的枝桠进行了研究，用以比较它们树皮存留率的差异，但详细深入的研究是在八十年代以后，以R. L. Edmonds, C. E. Pertson为代表研究不同层次，不同径级研究枝桠的分解速率，我国在此领域的研究尚属空白。本文以长白山阔叶红松林带的四个树种：红松，白桦，落叶松，色木为对象探讨了它们枝桠的生物量，分解速率，分解过程中的养分动态以及枝桠堆对更新和火灾的影响。采伐后0-14后间，迹地上枝桠干重为31.96-9.60T/ha，通过对7个年代采伐迹地上枝桠堆面积估算后得知，枝桠堆平均占地为11.53%，以1CM直径累计值对应的枝桠堆的高度（Y：CM）为因变量，分解时间（X, yr）为自变量，则枝桠堆高度随时间变化的过程可以描述为：Y = 1.288 - 0.000889 X~2 r = -0.9896。本文以密度（Y: g/CM~3）随分解年令（X: yr）的变化来表示分解速率。四十年代样品用排水法求出来的密度与用园柱法求出的密度有如下相关关系：Y排 = 0.0129 +2.316 Y园，r = 0.94 Y表示密度（g/CM~3）。我们用单项指数模型描述分解速率：落叶松：Y = 0.4701 * exp (-0.01783 X) r = -0.927 色木: Y = 0.6742 * exp (-0.07824 X) r = -0.988 红松：Y = 0.5349 * exp (-0.03421 X) r = -0.927 桦树：Y = 0.5316 * exp (-0.1139 X) r = -0.992 红松树皮的分解模型近似于直线：Y = 0.5258 - 0.01133 X r = -0.984 落叶松，红松，色木，桦树的分解常数分别为：0.01783, 0.0.41, 0.0782, 0.1139。依此预测分解原密度的95%所需要的时间分别为：168年，87.6年，38.3年，26年。可以看出这四个树种分解从难到易的顺序为：落叶松 > 红松 > 色木 > 桦树。对枝桠密度的差民显著性检验可以说明：红松样品层次对分解的影响显著而径级对分解的影响仅在下层显著。随着分解的进行，样品的重量损失，我们也探讨了密度的降低与失重百分率之间的关系。桦树样品下层失重比上层快，说明淋溶作用对桦树样品失重的贡献不大。温湿度是影响分解的最主要的生态因子。枝桠堆上下层的湿度差异特别明显。分解时间越长，径级对含水量的影响越显著。水分含量（Y：%）随年代（X: yr）变化的趋势为：Y = 36.18 - 0.004337 X~2 (4-7cm径级）Y = 33.64 - 0.01097 X~2 (1-4cm径级） 温，湿度影响土壤动物及微生物种群分布及数量，进而影响到枝桠的分解速率，分解过程中元素动态变化是：C基本上恒定，全N含量趋于增高。径级对红松N的累积有影响。下层4-6cm径极累积最快，其次是上层4-6cm。层次的影响仅限于红松，除72年以外上层 > 下层。其它元素如P, Mg++， Ca++总的趋势是随分解过程而增加。土壤中的C元素含量受立地条件的影响，但是枝桠堆下面土壤C值高于对照。枝桠堆对森林更新和火灾均有影响。枝桠是林火的燃料，枝桠堆面积占采伐迹地的11.53%，这样减少更新面积。

Distributed Temperature Sensing System Based on Rayleigh Scattering BOTDA

A distributed temperature sensor based on Rayleigh scattering Brillouin optical time domain analysis (Rayleigh-BOTDA) is proposed in this paper. The sensor uses Rayleigh backscattering effect of microwave modulated pulse base sidebands as probe wave and a high sensitive photon counting detector for Brillouin signal intensity detection. Compared with a conventional BOTDA system, the Rayleigh-BOTDA effectively suppresses polarization-induced signal fluctuation resulting in improved signal intensity. The experimental scheme presented is simplified by using a single laser with one-end access. The temperature accuracy of the new sensing system was demonstrated as 1 degrees C on spatial resolution of 3 m.

糖原酸酯合成方法的研究以及二环糖胺的合成

在糖化学中，糖原酸酯是一类重要的合成中间体，广泛运用于1,2-反式糖苷的合成，尤其对于寡糖的立体选择性合成具有重要的价值。目前文献报道的制备糖原酸酯的方法大多存在对环境不友好的问题。本文对传统的糖原酸酯制备方法进行了改进，通过研究发现无机碱也能够有效地催化合成糖原酸酯。以溴代糖和醇（或糖基受体）为原料，在无机碱、四丁基溴化铵、乙腈的体系中，合成了一系列简单醇糖原酸酯和糖-糖原酸酯。 聚乙二醇及其衍生物作为有机反应的溶剂和催化剂在有机化学中有广泛的应用。本文阐述了一种以溴代糖和醇（或糖基受体）为原料，在无机碱和聚乙二醇二甲醚反应体系中合成糖原酸酯的方法。该方法中，聚乙二醇二甲醚即作为绿色溶剂又作为催化剂，反应条件温和、环保、高效。 糖胺是一类重要的糖苷酶抑制剂，已在糖尿病和其他代谢紊乱等疾病的治疗中发挥了极其重要的作用。本文提供了一种合成一类具有潜在的糖苷酶抑制活性、结构新颖的二环糖胺的途径。该合成思路是以1-叠氮基-2-C-乙酰甲基-3,4,6-三-O-苄基-2-脱氧-β-D-葡萄糖为原料，经二环糖亚胺中间体，通过二环糖亚胺还原或加成得到一类二环糖胺。 Sugar orthoesters as one of the most important intermediates in carbohydrate chemistry, are used extensively in the synthesis of sugar 1,2-trans-glycosides, especially oligosaccharide. These methods in the literature are mostly eco-unfriendly. Herein we described a modified protocol for the preparation of sugar orthoesters using inorganic base, by improving the conventional method. Our method involves the treatment of peracetylated or perbenzotlated glycosyl bromides with alcohols in the presence of a quaternary ammonium salt and an inorganic alkali in acetonitrile solvent, affording both simple sugar orthoesters and sugar-sugar orthoesters. Polyethylene glycol and their derivatives as solvents or catalysts play a significant role in the organic reaction. We developed a novel and environmentally benign methodology towards the synthesis of sugar orthoesters, which are prepared by the reaction of peracetylated or perbenzotlated glycosyl bromides and alcohols in the presence of dimethyl ether of polyethylene glycol as either the reaction medium or catalyst. Glycosylamines and pseudo-glycosylamines have been tested against various glycosidases, and applied to the treatment of diabetes and other metabolic disorders. We presented a route of the synthesis of a bicyclic glycosylamine as a potential glycosidases inhibitor with unique structure. Reduction of 2-C-acetlymethyl-β-glucopyranosyl azide derivative firstly produced a bicyclic glycosylimine intermediate, and subsequently the bicyclic glycosylamine and its derivatives would be prepared through the selective reduction or addition the C=N double bond of the bicyclic glycosylimine intermediate.

花椒的化感作用对凋落物分解的影响及机理研究

花椒（Zanthoxylum bungeanum）是川西干旱河谷地区重要的经济作物，化感作用是花椒连作障碍的重要原因之一。花椒凋落物分解是影响花椒林地土壤肥力及花椒产量的重要因素，因此系统研究花椒化感作用是否对花椒凋落物的分解产生影响可以为解决花椒连作障碍导致的产量下降等问题提供科学的理论依据。本文通过室内模拟实验研究了花椒凋落物的四个分解动态以及分解后凋落物浸提液对花椒林地土壤性质的影响；通过野外盆栽实验研究了花椒凋落物浸提液对花椒幼苗的生长、花椒凋落物的质量及土壤性质的影响。最终从生理生化角度揭示了花椒的化感作用对凋落物分解的影响机理，为深入解决花椒连作障碍问题、对花椒凋落物采取有效的人工措施提供了科学的理论依据。主要的研究结果如下： 1. 室内分解实验证明，花椒凋落物在分解的60 d 内分解速率呈现由大到小的变化趋势，并且凋落物分解呈现明显的毒性动态。凋落物在分解的10 d、30 d 时，分解速率较大，30 d 以后分解速率显著降低。凋落物分解的10 d 左右酚酸释放量最大，此时凋落物的毒性最大，凋落物分解到10 d 以后，酚酸释放量逐渐减少，凋落物的毒性也逐渐减小。 2. 四个分解动态的花椒凋落物浸提液对土壤化学性质产生了显著的影响。花椒凋落物在分解的60 d 内，其浸提液使土壤pH值均显著的增加。分解0 d 的凋落物浸提液显著的降低了土壤铵态氮的含量，抑制了纤维素分解菌的生长；分解60 d 的凋落物浸提液显著的降低了土壤酚酸含量，增加了土壤有效磷的含量；分解30 d 和60 d 的凋落物浸提液均显著的促进了好气性纤维素分解菌的生长。这说明花椒凋落物在分解过程中呈现出明显的毒性动态：凋落物分解的初期毒性作用较大，随着分解的继续进行特别是在分解的30 d 以后，其毒性作用慢慢降低。 3. 花椒凋落物浸提液对花椒幼苗表现出明显的化感作用。不同浓度的浸提液对花椒幼苗地上及地下生物量、叶面积均产生了显著的抑制作用，并且随着浸提液浓度的升高抑制作用加强。凋落物浸提液对叶片厚度的影响较小，只有Y1对叶片厚度的生长抑制作用显著。 4. 花椒的化感作用改变了凋落物的质量，并对凋落物分解产生了显著的影响。对花椒幼苗用不同浓度的凋落物浸提液进行处理，Y1使凋落物有机碳含量、木质素含量、C/N、木质素/氮显著降低，纤维素含量显著升高；Y3使凋落物有机碳含量、木质素含量、C/N、木质素/氮显著升高。花椒凋落物质量的改变显著的影响了凋落物的分解，凋落物的分解速率大小依次为：Y1（10.15 a-1）> Y2（8.71 a-1）> CK（6.41 a-1）> Y3（5.08 a-1）。 5. 花椒的化感作用改变了土壤性质，并对凋落物分解产生了显著的影响。对花椒幼苗用不同浓度的凋落物浸提液处理的同时，也改变了土壤性质。不同浓度的凋落物浸提液显著的升高了土壤pH值、有机碳含量。各种浓度的凋落物浸提液对土壤多酚氧化酶的活性均起到了显著的促进作用。凋落物浸提液Y1对土壤纤维素分解酶的活性、细菌和真菌的生长也具有显著的促进作用。土壤性质的改变显著的影响了凋落物的分解，凋落物的分解速率大小依次为：Y1（10.30 a-1）>Y2（9.60 a-1）>CK（6.41 a-1）>Y3（6.29 a-1）。 6. 不论是凋落物质量发生改变还是土壤性质发生改变，在凋落物分解的整个过程中，C元素始终处于单调净释放的状态，并且C释放量与分解速率成显著的正相关，即凋落物分解越快，凋落物C释放量越大。凋落物分解过程中，均出现了酚酸大量释放的情况，并与凋落物分解速率成显著正相关。凋落物分解后的木质素含量、木质素/氮均增加，并且随着浸提液浓度的升高，凋落物木质素含量、木质素/氮升高。 Zanthoxylum bungeanum is an important economic crop in dry valley of the Minjiang river (Sichuan, Southwest China), but allelopathy is one of the important reasons for its continuous cropping. Zanthoxylum bungeanum litter decomposition affects Zanthoxylum bungeanum soil fertility and its output. So systemically investigate if allelopathy affects litter decomposition could provide the scientific methods to solve the problem of output fall caused by the continuous cropping. In this paper, the releasing dynamics of phenolic acid during Zanthoxylum bungeanum litter decomposition (0, 10, 30 and 60 days) and the effects of its aqueous extract on soil chemical properties were investigated via the laboratory study. Effects of Zanthoxylum bungeanum litter aqueous extract on the growth of young Zanthoxylum bungeanum seedlings, litter qualities and the soil qualities were investigated via the field study. Finally, we open out the action manner of Zanthoxylum bungeanum allelopathic effect on the litter decomposition, and provide the theoretical basis to solve the Zanthoxylum bungeanum continuous cropping. The main results showed that: 1. The laboratory litter decomposition experiment showed a trend of decomposition rate from large to small and an occurrence of phytotoxicity with clear dynamic patterns during Zanthoxylum bungeanum litter decomposition. The litter decomposition rate was larger at the tenth and 30th day during 60-day litter decomposition and gradually decreased after 30 days of litter decompostion. The releasing quantity of the litter phenolic acid was the highest at the tenth day, and here, the litter toxicity was the biggest. The releasing quantity of the litter phenolic acid gradually decreased after 10 days of litter decomposition, so the phytotoxicity of litter was gradually decreased with the litter decomposition. 2. The Zanthoxylum bungeanum litter aqueous extract after four decomposition stages had significantly effect on the soil chemical qualities. The pH value in soil was significantly increased in litter aqueous extract of four decomposition stages. The NH+4-N concentration was significantly decreased in soil amended with litter aqueous extract of 10-day decomposition which inhibited the growth of Aerobic cellulose-decomposer. The growth of soil Aerobic cellulose-decomposer was promoted by the litter aqueous extract of 30-day decomposition. Available phosphorus concentration was significantly increased and phenolic acid content was significantly decreased in soil amended with litter aqueous extract of 60-day decomposition which promoted the growth of Aerobic cellulose-decomposer. The study results showed an occurrence of phytotoxicity with clear dynamic patterns during Zanthoxylum bungeanum litter decomposition. The phytotoxicity of litter was the largest at the initial stage, but the phytotoxicity gradually decreased with the litter decomposition, especially after 30 days of decomposition. 3. The field study indicated that the Zanthoxylum bungeanum litter aqueous extract had significant allelopathic effects on the growth of young seedlings.Different concentration aqueous extract had signinficant inhibiting effects on biomass and leaf area of young seedlings. The inhibiting effect on the biomass strengthened with the litter aqueous extract concentration augment. Litter aqueous extracts had less effect on the leaf thickness, and only Y1 had significant inhibiting effect on the leaf thickness. 4. The Zanthoxylum bungeanum allelopathy had significant effect on the litter qualities and the litter decomposition. Treating the young Zanthoxylum bungeanum seedlings with different concentration of litter aqueous extracts, the leaf litter organic C, lignin, C/N and lignin/N all decreased and the cellulose content increased under Y1 treatment. The leaf litter organic C, lignin, C/N and lignin/N all increased under Y3 treatment. So the litter decomposition was significant affectded by the litter qualities, and the litter decomposition rate was Y1(10.15 a-1)> Y2(8.71 a-1) > CK(6.41 a-1) > Y3(5.08 a-1). 5. The Zanthoxylum bungeanum allelopathy had significant effect on the soil qualities and the litter decomposition. Treating the young Zanthoxylum bungeanum seedlings with different concentration of litter aqueous extracts, also changed the soil qualities. Different concentration of litter aqueous extracts had significant effects on the soil pH and organic C content. Every concentration of litter aqueous extracts accelerated the soil Polyphenol Oxidase activity and Y1 accelerated the soil Cellulase activity, the number of soil bacteria and fungi. So the litter decomposition was significant affected by the soil qualities, and the litter decomposition rate was Y1(10.30 a-1) > Y2 (9.60 a-1) >CK(6.41 a-1)>Y3(6.29 a-1)。 6. Whether the litter or soil qualities changed, the litter C element at the state of release at all times during the litter decomposition, and the release quantity increased with the decomposition rate augment. Litter released plentiful total penolics content during decomposition, and the release quantity had the positive correlation with the litter decomposition rate. The litter lignin content and the lignin/N all increased with the litter aqueous extracts concentration augment after litter decomposition.

牦牛粪便对青藏高原东部高寒草甸土壤养分系统的影响

川西北高寒草甸位于青藏高原东部地区，是我国四大牧区之一，也是长江和黄河等江河源区的重要水源涵养功能区。近几十年来，大量牦牛粪便被牧民作为生物能源、肥料或者食用菌产业的原料而利用，为草原生态系统的养分平衡增加了生态风险。鉴于在青藏高原地区针对牦牛粪便的相关研究尚未见报道，本文从粪便和土壤养分相互变化趋势的角度出发，研究了粪便在夏秋两季的分解状况和粪便其下及其周围土壤的养分变化。通过此研究，将有助于了解牦牛粪便在自然状态下的分解速率以及粪便对土壤养分及土壤微生物生物量的影响，为粪便对草地土壤生态系统的贡献提供概念性认识，同时也为高寒草甸草地这种脆弱生态系统的可持续管理提供理论依据。 针对牦牛粪便自身养分释放及其对土壤在时间和空间尺度上的影响，本文通过模拟牛粪堆积，在不同时间和固定区域内对牛粪和土壤进行了夏秋两季的采样测定，分析了牛粪及土壤NO3--N、NH4+-N、速效K、无机P、有机C、全N 和全P 含量随时间的变化趋势。得到如下结果： 1. 在研究区域内，牛粪对草地生态系统具有较强的养分（N、P）贡献能力。据初步统计，其估值大致为氮素699~932 kg ha-1，P 素为110~147 kg ha-1。牛粪（湿重、干重）在夏秋季节的分解速率具有较大差异，夏季显著快于秋季。夏季牛粪湿重、干重在2 个月左右之后分别降为初期的14%和24%，而秋季同期分别降为35%和52%。牛粪养分（NO3--N、NH4+-N、速效K、无机P、有机C、全N 和全P）的分解速率在夏季也要显著快于秋季。秋季经过2 个月左右的分解之后，牛粪以上含量分别降至初始态的32%、60%、36%、64%、58%、63%和43%，远高于夏季的同期水平。 2. 在不同季节，牛粪周围的土壤养分（NO3--N、NH4+-N、速效K 和无机P）含量变化随时间改变呈现相同的趋势。但是，牛粪周围不同远近下土壤养分随时间的动态变化幅度略有不同。粪下土壤养分含量随时间变化波动较大，距粪便越远，随时间变化的变幅越为平缓。总体来说，在夏季由于粪便分解较快，对土壤养分的持续作用时间不及秋季，秋季粪便分解变慢，表现出养分的缓释特征。其次，牛粪对粪下土壤影响的持续时间也长于对周围土壤的作用时间。 3. 粪便对土壤养分（NO3--N、NH4+-N、速效K、无机P）影响的范围在不同季节具有差异。夏季要高于秋季，但对周围土壤养分影响的持续时间低于秋季。在夏季短期内，牛粪对土壤NO3--N 和速效K 含量的影响范围能够超过30cm，而对NH4+-N 和无机P 的影响范围则介于10cm 和30cm 之间。在2 个月左右之后，牛粪对周围土壤养分的影响能力基本消失。在秋季，牛粪对周围土壤养分影响范围难以达到30cm 处。粪便在夏季对其下土壤和周围土壤的有机C、全N 和全P 含量并无显著影响，但在秋季能显著增加其下土壤有机C、全N 和全P 含量。 4. 牛粪在秋季对土壤SMB-C、SMB-N 和SMB-P 含量的影响能够持续2 个月以上，由于秋冬季节牛粪分解缓慢，因此推断这种效应持续时间至少能够1 年左右。另一方面，牛粪在秋季对土壤SMB-C、SMB-N 和SMB-P 含量的影响范围主要集中在其下土壤，而周围的影响效应并不明显。 The grassland on the eastern fringe of Qinghai-Tibetan Plateau was one of the four greatest pasture zones in our country and the main water conservation function zones in the hesastream of Yangtse River and Huanghe river. Rencent years, lots of dung in this area was used as biological energy, fertilizer or material of fungoid growing, leading to high risk of nutrient banlance in grassland ecosystem. In view of the researches on the impact of yak dung in this area are relatively rare, the present study focused on the relationship of dung and soil nutrient transformation in sunmer and autumn, which could profoundly illuminate the mechanism of dung decomposition and the effect of dung on soil chemical properties and soil microbe biomass. The present study also contributed to a basic understand and provided scientific management in the high-frigid ecosystem. Decomposition of yak dung and its effect on soil chemical properties in eastern grassland of Qinghai-Tibetan Plateau were determined. The study simulated the real dung pats, took dung and soil samples at different time and fixed-point in summer and autumn. The samples were analysed for NO3--N, NH4+-N, available K, inorganic P, total organic C (TOC), total N (TN), total P (TP). It was concluded that: 1. In study area, the yak dung supplied to ecosystem substantial nutrient. It is estimated that the N contribution of dung was approximately 699~932 kg ha-1, P contribution was approximately 110~147 kg ha-1. The rate of yak decomposition was more rapid in summer than autumn, the wet and dry weight of yak decreased to 14% and 24% respectively after 2 months when dung excreted in summer, with 35% and 52% in autumn. The content of NO3--N、NH4+-N、available K、inorganic P、TOC、TN and TP in dung decomposed more rapid in summer too. After 2 months when dung excreted in autumn, the content of above nutrient decreased to 32%、60%、36%、64%、58%、63% and 43% respectively，which were significantly higher than summer. 2. The content of NO3--N、NH4+-N、available K and inorganic P in soil around dung had the same transformation trend in each season, whereas it was distinguishing at different gradient of distance from dung, the nutrient in soil below dung had the most significant change while the more far from dung, the less change in soil. It was concluded that the yak dung had prolong impacts on soil in autumn compared with summer, besides, it aslo showed that the yak dung had protract effect on soil below dung compared with soil around dung. 3. The yak dung had expansive impact on soil around dung in summer whereas had relatively short effect compared with autumn. In short-term at summer, there was a significant increase about the content of NO3--N and available K around 30cm radius from dung pat while the content of NH4+-N and inorganic P between 10cm to 30cm. After 2 months, the impact almost disappeared. In autumn, the effect was hard to reach 30cm. The yak dung had no significant effects on the content of TOC、TN and TP in soil below or around dung in summer whereas there was a obvious increase in soil below dung pat in autumn. 4. The duration of effect of yak dung on soil microbial biomass(SMB) C、N and P was at least 2 months, maybe even more than 1 year. On the other hand, the impact of dung on SMB-C、SMB-N and SMB-P mainly acted on soil below dung while no obious effect on soil around dung.

自养氨氧化混合种群特性和共存机理初步研究

组特殊自养氨氧化混合种群，表现：无机环境种群生长迅速、生物量高；在一个完全无机的自养生长环境中，不仅保持高氨氧化速率，并出现丰富的异养微生物种群；该种群置于异养、厌氧环境中，迅速表现出产氢特征。对于这样一个特殊的生态体系，研究其共生机理，以及联接这些种群之间的碳源和能源问题，将具有非常重要意义。我们拟从种群特征、细胞表面分泌产物、游离体系产物多糖、蛋白和脂肪酸方面开展研究。 第一部分，自养氨氧化混合种群的基本特征。采用氨氧化培养基，进行种群氨氧化特征研究；采用扫描电镜观察自养混合种群的微观特征；沉降、离心去除微生物种群，分析水相中的总有机碳、糖类等物质；利用LB培养基进行种群的分离、纯化，并采用DGGE手段对微生物种群结构进行分析。结果表明，接入菌种后（2/5000（V/V）），培养液中氨（200mg/L）在3－5天内快速降解；亚硝酸盐与氨氮变化呈负相关趋势，仅有少量硝酸盐含量（< 30mg/L）。氨氧化种群的生物量增长与氨氧化趋势一致，初始生物量7.75 mg/L(蛋白含量)，3-5天后生物量快速增长，并达到最高63.06 mg/L（蛋白含量）。电镜图片显示，种群外包裹一层粘液。离心除去菌体后，检测培养液总有机碳和糖的含量，同样表现出与生物量增长相似的特征，分别由初始的3.73、2.35 mg/L，3－5内天迅速增加，并分别达到最大值35.19、27.45 mg/L。经初步分离、纯化并对纯化菌株进行测序，获得了10株异养微生物分别为布鲁氏菌科苍白杆菌属、纤维单孢菌、类芽孢菌属、黄杆菌属、无色杆菌、鞘脂单胞菌、嗜麦芽寡养单胞菌、噬氢菌属、硫红球菌、假单胞菌；DGGE显示，约有20分条离带，我们对其中的两条优势条带进行切割回收测序，鉴定为欧洲亚硝化单胞菌（Nitrosomonas eur）。 第二部分：混合种群自养-异养菌共生的可能机制。在对微生物种群特征初步分析基础上，针对胞外糖类组分可能被微生物代谢分解，我们重点对微生物细胞蛋白质与糖类进行分析。采用超声结合RIPA裂解液裂解，SDS-PAGE电泳分析混合种群总蛋白种类，并通过氨基酸分析仪及红外光谱法分析氨基酸组成及蛋白红外特征。采用超声破碎结合反复冻融对细胞样品进行处理，提取液采用醇沉、Sevage脱氮白，凝胶过滤方法脱盐和分级分离。对提取物的糖分析包括：紫外扫描，红外光谱，核磁共振，单糖组成分析；扫描电镜观察菌群破裂现象。SDS-PAGE分析结果表明：氨氧化种群不同生长阶段都显示出42kD蛋白表达量很高，d4时42kD蛋白表达已经很强，4-7d内一直持续这种过量表达，直到d8后表达开始减弱。说明42kD蛋白可能与氨氧化密切相关。红外光谱分析显示：细胞提取物的特征峰分布在3427.42cm-1、1718.18 cm-1和1681.72 cm-1、1160.07和1086.74 cm-1，分别对应为OH、 C=O、C－O－C基团，表明具有蛋白的典型特征；氨基酸分析显示蛋白中的Gly,Asp,Ala,Glu含量相对较高。 提取物中胞外多糖分离谱图得到不均一组分，共得到6个收集峰；紫外扫描在201－213 nm处有多糖吸收峰，同样表明多糖成分不均一性；多糖红外光谱特征峰主要分别在3400.49 cm-1、2920.28 cm-1、1154.54和1087.52 cm-1，对应OH、－CH2－ or CH 、C－O－H or C－O－C等多糖特征基团；多糖提取物核磁共振1H d4.3～5.9之间出现强吸收峰，这是1H中，多糖存在的明显证据，1H NMR中，其中O-乙酰基的甲基上的氢信号为d1.1～1.3之间。糖肟全苯甲酸酯衍生物的HPLC测定中，得到单一的单糖峰，由于时间问题，还未进行更深入的试验；电镜图片显示，种群中的细胞有大量的破裂现象。 实验表明，自养氨氧化混合种群显示出快速的氨氧化速率，氨氧化过程生物量和有机质的增加明显。微生物种群包裹粘液层，并分离纯化出大量的异养菌；去除菌体后的游离培养液中存在有机质（包括多糖）说明无机自养生长体系中存在异养菌生长、繁殖的二次碳源；细胞提取物中蛋白条带数目多、种类丰富；细胞多糖提取物具有明显的多糖特征，以及单糖的存在。结合种群的显微特征和游离体系中的有机质的检测结果，我们认为，无机自养生长体系中，种群细胞生长过程中发生的破裂现象可能是导致大量的蛋白、多糖释放到游离胞外，并成为其他异养菌生长的碳源和氮源。这可能是自养体系中，大量异养菌共生的可能机制，至于是什么原因引起种群生长过程中产生的破裂现象，还有待下一步深入研究。 A group of mixed autotrophic ammonia oxidizing populations, having much biological characteristic tested by concerned personnel for pilot test: Performed rapid population growth and obtained high biomass in inorganic environment; Not only maintained a high rate of ammoxidation, promoted a wealth of heterotrophic microbial populations growth in a totally inorganic and autotrophic growth environment; Placed in heterotrophic and anaerobic environment,had the performance characteristics that could rapidly produce hydrogen.For such a special ecological system, Study its symbiotic mechanism and the connection between these populations of carbon and energy issues, will have a very important significance. We intended from the characteristics of the population, the secretion product of cell surface, free substance in the liquid medium like polysaccharide, protein and fatty acids carrying out research. Part I: The basic features of mixed autotrophic ammonia oxidizing populations . Use inorganic liquid medium, processed study for ammonia oxidation characteristics of the population; we used scanning electron microscopy to get micro-features of autotrophic ammonia oxidizing populations .The medium was carried out settlement and centrifugal then removed the microbial populations, after all of that we analysis the water phase for total organic carbon(TOC), carbohydrate and other substances; Solid ammonia oxidizing medium was adopted to separation and purification of population, DGGE means was for structure analysis of microbial population. The results showed that after the inoculum of bacteria (2 / 5000 (V / V)), ammonia in the culture medium (200 mg / L) was rapid degradation in 3-5 days; ammonia and nitrite have the negative correlation between changes in the trend, then only a small amount of nitrate content (<30mg / L). The biomass growth of ammoxidation population in line with the trend of ammonia oxidation, the initial volume of it was 7.75 mg / L (protein content), in 3-5 days upto 63.06 mg / L (protein content). Electron microscope image showed, the populations were wrapped in a layer of mucus, including the a large number ruptted micorbe , Centrifuge to remove bacteria, then detected the medium for total organic carbon and sugar content, result took on the same characteristics with biomass growth, that were from the initial 3.73、2.35 mg / L respectively, in 3-6 days achieved rapid increase in the maximum to 35.19、27.45 mg / L respectively. After initial separation、 purification ,then processed sequencing to strains purified and got the result that there were 10 heterotrophic microorganisms : Brucella Branch pale bacillus, Cellu lomonas, Bacillus species category, a Flavobacterium, colorless Bacteria, Aeromonas sheath fat, little support maltophilia Aeromonas, macrophages species hydrogen, sulphur-MI, Pseudomonas bacteria spores; DGGE display, there were 20 separation bands approximately. Part II: Mixed populations that autotrophic - heterotrophic bacteria symbiotic mechanism. On the basis of preliminary analysis of microbial population characteristics, aiming at extracellular carbohydrate components might be decomposition by microbial, we focused on microbial cell protein and carbohydrate analysis. Using ultrasound combined with RIPA lysis cracking the cells, SDS-PAGE electrophoresis analysis the total protein species of the population, and through the amino acid analyzer studied the compositions of amino acid and infrared spectroscopy analysis of a protein infrared characteristics. Using ultrasound combined with repeatedly freezing and thawing to treated the cell sample, then took the means that alcohol precipitation, deproteinization by Sevage, gel filtration aimed at desalination and grade separation to deal with the lysates . The extraction of sugar analysis included: UV scanning, IR, NMR, single-sugar composition analysis. SDS-PAGE analysis showed that: 42 kD protein expression was very high at different growth stages of mixed autotrophic ammonia oxidizing populations , on the fourth day, 42 kD protein expression had been very strong, 4-7d, it had continued this excessive expression, then started to weaken after 7 days. 42 kD protein that might be closely associated with ammonia oxidation. Infrared spectral analysis showed that: cell extracts with the characteristic that the peak distribution in 3427.42 cm-1、1718.18 cm-1 and 1681.72 cm-1、1160.07 cm-1 and 1086.74 cm-1 corresponding to OH、C = O、C-O-C Groups which had the typical characteristics of protein; and analysis showed that amino acids including Gly, Asp, Ala, Glu ,the content in the protein is relatively high. Exopolysaccharide in the extracts had the separation map that it was uneven, received a total of six collection peaks by the detection mode of phenol-sulphruic acid method ; ultraviolet scan in the 201-213 nm department had polysaccharide absorbing peak, the same ingredients that polysaccharide heterogeneity; infrared polysaccharide spectral characteristics of the main peak at 3400.49 cm-1, 2920.28 cm-1, 1154.54 and 1087.52 cm-1, corresponding OH,-CH2-or CH, C-O-H or C-O-C;and other characteristics of polysaccharide group; 1H NMR of polysaccharide extract appeared absorption peak between d4.3 ~5.9, which is the apparent evidence of polysaccharide, In 1H NMR, the hydrogen signal of one of O-acetyl was between 1.1 to 1.3. The determination of Sugar oxime whole benzoate derivatives by HPLC, there was a single-sugar peak, as a matter of time, yet more in-depth test. Summary: Mixed autotrophic ammonia oxidizing populations show us that it had the ability in ammonia oxidizing and it was great, organic matter and biomass increased significantly in the process of ammonia oxidation. Microbial populations was wrapped up slime layer, the phenomenon of cell breakdown obviously, and there were a lot of separation and purification of the heterotrophic bacteria; a lot of organic matter (including polysaccharides)remined in the medium that removal of cell indicated the inorganic system existed secondary carbon sources that could be used by the heterotrophic bacteria ; there were a large number proteins bands of cell extract, rich variety; cell extracts of polysaccharide had obvious characteristics of polysaccharide, and the existence evidence of single-sugar. Combined population of microscopic characteristics and free of organic matter in the test results, we believe that the health of inorganic system, population growth occurred in the course of the breakdown of the phenomenon is likely to lead to a lot of protein and polysaccharide released into the extracellular free, And other heterotrophic bacteria use them to the growth as carbon and nitrogen. This may be autotrophic system, the large number of heterotrophic bacteria symbiotic mechanism.