东北多年冻土对气候变化的响应

近地表面多年冻土对寒区生态系统的植被覆盖、水文条件、土地利用和工程建设具有重要影响，随着气候变化研究的广泛开展，区域冻土环境的变化也成为学者关心的重要议题。中国东北的多年冻土处于欧亚大陆多年冻土带的南缘，多年冻土不如以北地区发育，是十分脆弱的多年冻土。然而，多年冻土在东北寒区生态系统中却起着重要的作用。若东北多年冻土发生退缩，则有可能加速落叶松北移和湿地退缩的过程，也会对C的释放产生重要影响。因而探明现实气候条件下东北区域多年冻土的影响因子和发育状况以及未来气候条件下多年冻土的退缩趋势，将有助于促进东北寒区生态系统的冻土和其它学科研究，同时也可为寒区开发建设提供有意义的参考。 本研究从分析东北多年冻土的主要影响因子——气候、地形和土壤条件等入手，准确地掌握了多年冻土的发育状况，并以此为根据进行了景观尺度上多年冻土分布信息的提取和融深信息的研究。同时，在区域尺度上对多年冻土的现实分布和未来气候条件下多年冻土的可能分布状况进行了探讨。最终得到以下重要结论： （1）冻结数对东北多年冻土分布具有重要的指示作用 冻结数模型具有明确的物理意义，可以指示多年冻土的发生状况。研究中，利用地形、纬度等因子，结合气温和降水数据模拟了现实气候条件下东北地区的冻结数值；并依据冻结数模型的区划标准对东北多年冻土进行分区。结果表明，冻结数在指示多年冻土分布时具有重要作用。 （2）土壤含水量、地形坡度和群落因子对多年冻土具有重要影响 以大兴安岭呼中国家级自然保护区为例，调查了该区多年冻土活动层厚度，并利用多重对比分析和相关分析的统计方法，对多年冻土活动层的影响因子进行了分析。结果表明，多年冻土活动层厚度与多个环境因子之间存在着复杂的关系。其中，土壤表层含水量与活动层厚度具有极显著的负相关关系（P<0.001），其相关系数在0.90以上，说明含水量越高，活动层厚度越浅。地形坡度和活动层厚度的相关性也达到显著水平（相关系数为0.321，P=0.006），表明坡度越陡，活动层厚度越大。几乎每个样带的海拔与活动层厚度都有显著的相关性，但在整体研究区域内海拔与活动层厚度不存在相关性。这说明活动层厚度的变异仅在本研究的样带尺度上具有规律性，而在稍大尺度上这种规律性就消失了。对于不同的群落活动层厚度的多重对比分析表明，群落的差异对活动层厚度也有明显的影响，其中狭叶杜香-泥炭藓群落（Larix gmelini-Ledum palustre var. anqustum-sphagnum magellanicum）更有利于多年冻土的保存。 （3）景观尺度上的多年冻土分布状况 在景观尺度上，以呼中国家级自然保护区为研究区，应用神经网络方法，同时以土地覆盖、等效纬度、坡向和土壤湿度多种影响因子为数据源，对多年冻土分布信息进行提取。结果表明，考虑土地覆盖、等效纬度和土壤湿度的数据源组合可以获得高精度最高的多年冻土分布信息，分类精度可以达到89.0%，多年冻土面积占研究区面积百分比达到46.71%，为780.1 km2。 （4）景观尺度上多年冻土的融深状况 研究考虑了包括植被和等效纬度两个影响活动层厚度的重要因子，并将Stefan公式进行变形，简化为包含热量条件的等效纬度因子和植被条件的C因子的函数关系。最后应用该函数关系模拟了呼中自然保护区活动层厚度空间分布，模拟结果的精度为87.25%。在模拟结果中，面积和所占比例最大的活动层厚度为70-80 cm间的活动层厚度，所占面积达到341.4 km2 ，占整个研究区面积的20.43%。而面积最小的活动层厚度为30-40 cm间的活动层厚度，面积为0.02 km2 。通过群落与活动层厚度的空间分布对比发现，呼中自然保护区占最大比例的活动层（70-80 cm）所对应的植物群落主要为落叶松-丛桦-笃斯-藓类群落（Larix gmelini-Betula ovalifolia-Vaccini uliginosum-moss）。说明呼中自然保护区冻土湿地植被主要以该群落类型为主，演替处于中间阶段。 （5）区域尺度上多年冻土的分布状况 利用证据权重法，以可能影响多年冻土分布的气候、地形和土壤等因子作为数据源，对研究区在现实气候条件下的多年冻土分布进行预测，获得了多年冻土在现实气候条件下的分布概率等信息。结果表明，当分布概率大于0.17时，划分出的多年冻土的精度最高，为78.71 %。此时，多年冻土面积为2.03×104 km2 ，约占研究区总面积的1.76%。 （6）东北多年冻土分布对气候变化的响应 利用空间代时间的方法和Kappa指数，对证据权重法在预测未来气候变化条件下多年冻土分布的准确性进行了验证，结果表明，证据权重法预测气候变化条件下多年冻土的分布状况是可行的。 在CGCM3模拟的三种气候模式下，多年冻土在2050年和2100年都将发生明显的退缩。2050年，SRES A1、SRES A2和SRES B1三种气候情景下多年冻土的面积分别为786.38 km2，705.94 km2和1 028.81 km2。与现实气候下多年冻土的面积2.03×104 km2相比，多年冻土分别退缩了96.13%，96.53%和94.94%。而2100年的模拟结果表明，三种气候情景模式下，多年冻土已经全部退化。 （7）气候变化条件下东北多年冻土的分区变化 研究将冻结数等值图与2000年中国东北冻土分区图进行叠加，计算了不同多年冻土亚区的边界对应的冻结数值，建立了利用冻结数进行中国东北多年冻土分区的标准。根据冻结数指标确定的新的中国东北冻土分区与原中国东北冻土分区进行Kappa指数认证。结果表明，冻结数分区标准更适用于中国东北多年冻土的区划。 利用新的冻结数分区标准对CGCM3模拟的三种气候情景模式下的气候变化数据进行区划表明，三种气候模式下东北多年冻土区在21世纪都会有非常明显的退缩。2050年时冻土区缩减了37.7%-42.6%，2100年时缩减了62.5%-74.0%。同时，研究结果显示，东北多年冻土区域的退缩不仅发生在多年冻土区的南界，同时多年冻土的中心退缩也较为明显，即大片连续多年冻土亚区和大片连续—岛状多年冻土亚区的退缩最为剧烈。2050年时，三种气候情景下，大片连续多年冻土亚区将退缩88.8%以上；2100年时，SRES A2模式下，大片连续多年冻土亚区将完全消失。

不同水分管理下稻田CH<,4>和N<,2>O的排放及其微生物学过程

大量研究表明，农田水分状况发生变化对CH<,4>排放有重大影响，水稻生长期的晒田处理不仅有利于植株生长而且能增加CH<,4>氧化，减少CH<,4>生成.但近年来注意到有利于控制CH<,4>排放的水分管理措施往往会促进N<,2>O排放，而其机理及对大气净温室效应的影响报道甚少.该文对不同水分管理下CH<,4>和N<,2>O的排放进行了定量分析并对温室效应的贡献进行了估算;同时对二种气体排放的微生物学过程进行了研究，观测了相关微生物菌群数量及田间环境因子的变化，并对不同水分处理期间的土壤理化性质对CH<,4>和N<,2>O排放及微生物数量的影响作了进一步分析，为制定综合控制稻田CH<,4>和N<,2>O的排放措施提供了科学依据.

土壤氨基糖微生物转化过程与机理探讨

土壤氨基糖因其异源性和稳定性可用以指示微生物对土壤碳（C）氮循环的相对贡献。但由于氨基糖是微生物在土壤中长期残留的平衡结果，其数量变化无法准确反映在微生物作用下无机态氮（N）向氨基糖转化的动态过程和机制，从而使氨基糖对土壤氮内循环的指示作用受到限制。如果能够利用新的技术手段研究土壤氨基糖的微生物转化过程，将使土壤氮素内循环研究产生突破。同位素技术是研究土壤C，N转化过程的有效手段。但是研究特定化合物如氨基糖的微生物转化过程还需要新的技术支持，本研究首先建立了稳定同位素培养－气质联机技术测定土壤氨基糖同位素富集比例新方法。对于15N培养样品，由于氨基糖分子中只有一个N原子，15N富集比例可通过m/z（F+1）与F相对丰度的比值计算；对于13C培养样品，由于葡萄糖c整体掺入形成氨基糖c骨架，所以利用m／z（F＋n）与F相对丰度的比值计算13c在土壤氨基糖中的富集（n为质谱碎片中骨架C原子数）。同位素富集用原子百分超（APE）表示。EI和cI两种方式测得的APE有很好的同一性，且不受土壤基质的影响，表明方法的可靠性和广泛适用性。利用以上方法，进行了土壤样品的同位素培养与测定，以跟踪土壤氨基糖微生物合成动态，进行氨基糖的微生物转化与更新研究。主要结论如下：1．当以葡萄糖为碳源且每周施入底物时，NH4+和NO3-均可被微生物迅速同化并进行氨基糖的合成。但NO3-必须被还原成NH4＋才能被微生物利用，因而NO3．存在短暂的滞后期，之后被微生物快速利用。氨基葡萄糖（GluN）和胞壁酸（MurN）不同的同位素富集特征表明，N源形态对细菌增殖无显著影响，但真菌更倾向于利用NH4+。在NO3-培养中氨基糖的增量及微生物对C的截获均小于NH4＋。2．分别利用u一13c一glucose一NH4十和glLlcose一ISNH4＋进行样品培养时，同位素富集趋势相同，但APE（13C）大于APE（15N），这种差别反映了了土壤微生物利用C，N的时间特征及土壤有机质含量对C，N循环的影响。3．以gtucose-15NH4+为底物时，施入N素频率的改变也会影响微生物的活性。尤其是细菌的快速生长受到N素不足的限制，转而代之以细菌和真菌的持续的低速生长。微生物活性的降低减少了对有机c的截获。DCD的加入有效抑制了NH4+向NO3一的转化，但对氨基糖的合成无显著影响。4．土壤氨基糖反映的主要是土壤中已经死亡了的微生物的一种长期过程而产生的残留，同土壤微生物量无明显的相关性。但经外加底物培养后，氨基糖同位素富集比例的变化则来源于微生物的转化，因而与微生物量碳有直接的相关性。5．从原理上说，在氨基糖的微生物合成过程中，葡萄糖没有发生C骨架的断裂，而是直接转化成为氨基葡萄糖的骨架。但在复杂的土壤基质中，氨基葡萄糖的合成必然受到葡萄糖其他生物化学过程的影响。使少量葡萄糖经酵解后再次参与己糖胺的合成。以全取代葡萄糖为底物时，葡萄糖碳骨架的断裂与重排不影响13c同位素的富集。但对于单取代葡萄糖培养来说，必须要考虑因葡萄糖碳骨架断裂而产生的同位素的重新分配，Mass（F+1）和Mass（F+2）的丰度变化的总和真正代表了氨基葡萄糖的同位素富集。6．添加有机物料和N素进行土壤样品培养时，对外加氮素的同化远低于相应的葡萄糖培养。碳源尤其是能源不足限制了N的转化。微生物分解高C加的有机物料需吸收外加N源以满足自身生长需要。N素的加入频率影落响微生物对外加N素的利用。当加入的N不能满足微生物分解有机物料的需要，就会降低微生物对有机物料的分解速度，使无机N向氨基糖态N转化速度降低。应用稳定同位素技术，发现施到土壤中的无机氮素可被微生物快速转化成某种形态有机氮，这种有机态氮处于不断转化循环之中，构成土壤有效氮的暂存"过渡库"，其中氨基糖是重要成分之一。过渡库现象的发现为氮肥的有效利用提供了新的思路。根据土壤有效氮"过渡库"的模型，氮月巴高效利用调控实际上就是土壤氮素微生物转化过程的调控。提高土壤无机氮素向土壤有机氮的转化速率和转化强度可以有效减少无机氮在土壤中的积累，从而降低肥料和土壤氮素的硝化和反硝化损失，提高氮肥利用率。研究还发现，土壤有效氮"过渡库"容量与循环速率不仅取决于N源自身性质，碳源的可利用性显著影响施入土壤的N素微生物转化特征。只有适当提高可利用碳源即活性碳源的数量，才能提高氮素的微生物同化，土壤有效氮"过渡库"容量，从而减少氮素损失。

模拟酸雨对杉木、木荷根系生长影响的研究

本文系一年模拟酸雨试验的结果。研究表明：（1）.模拟酸雨加速了土壤中Ca++、Mg++的淋失，土壤开始酸化。当土壤PH值低于4.5(KC1浸提),盐基饱和度低于75%时,活性铝溶出;（2）.土壤PH大于或等3.0（KC1浸提），模拟酸雨PH高于或等于3.0时，未显著影响一年生杉木、木荷的根系生物量和根系伸长生长，但PH2.0的模拟酸雨显著抑制了杉木根系生长，尤以小根的生长受抑制最为严重，而木荷则未受明显影响；（3）.一年生杉木在土壤中活性铝含量达到30.2mg/100g土，Al:Ca���为4.9时，根系生长已受严重抑制；一年生木荷在土壤中活性铝含量为40.6mg/100g土，Al：Ca���为15.8时，根系生长开始受影响；（4）.一年生杉木和荷根系生长受到的影响可能由于土壤中铝的存在影响了根系对钙的吸收。

野桂花的化学成分研究

首次从野桂花（Osmanthus yunnanensis Fr. P. S. Green）地上部分95%乙醇提取物中通过色谱分离得到20个化合物, 其中化合物20为新化合物。基于波谱数据它们被鉴定为(E)-阿魏酸二十烷基酯(1)、β-谷甾醇(2)、羽扇豆醇(3)、齐墩果酸(4)、7-oxo-β-sitosterol(5)、乙酰齐墩果酸(6)、(6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside(7)、rotundioic acid(8)、地榆糖甙Ⅱ(9)、27-O-(E)-对羟基肉桂酰-28-齐墩果酸(10)、27-O-(Z)-对羟基肉桂酰-28-齐墩果酸(11)、hycandinic acid ester(12)、绿原酸丁酯(13)、4,5-二咖啡酰奎尼酸丁酯(14)、4,5-dihydroxyprenyl caffeate(15)、28-O-β-D-glucopyranosyl rotundioic acid (16)、4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada-glycoside C, 17)、 4-β-D-glucopyranosyloxy-5-hydroxy-prenyl caffeate (aohada-glycoside A, 18)、β-胡萝卜甙(19)以及3-[O-β-D-(6-O-咖啡酰吡喃葡萄糖)]-甲基-2-烯-γ-内酯 (20)。化合物13、14、15和17有较强的α-葡萄糖甙酶抑制活性。当浓度为1 mg/ml时，它们对α-葡萄糖甙酶的抑制分别为61.5%、95.5%、72.1%、62.6%，活性高于阿卡波糖。 综述了木犀属植物化学成分及1993年以来苯丙素甙类化合物活性研究进展。 Twenty compounds were isolated from the 95% ethanol extract of the aerial parts of Osmanthus yunnanensis Fr. P. S. Green by chromatography for the first time. On the basis of spectral data, they were identified as (E)-ferulic acid eicosyl ester (1), β-sitosterol (2), lupenol (3), oleanolic acid (4), 7-oxo-β-sitosterol (5), acetyloleanolic acid (6), (6′-O-palmitoyl)-sitosterol 3-O-β-D-glucoside (7), rotundioic acid (8), ziyu glycosideⅡ (9), 3β-hydroxy-27-p-(E)-coumaroyloxy-olean-12-en-28-oic acid (10), 3β-hydroxy-27-p-(Z)-coumaroyloxyolean-12-en-28-oic acid (11), hycandinic acid ester (12), chlorogenic acid butyl ester (13), 4,5-di-O-caffeoylquinic acid butyl ester (14), 4,5-dihydroxyprenyl caffeate (15), 28-O-β-D-glucopyranosyl rotundioic acid (16), 4-(6-O-caffeoyl-β-D-glucopyranosyloxy)-5-hydroxyprenyl caffeate (aohada- glycoside C, 17), 4-β-D-glucopyranosyloxy-5-hydroxyprenyl caffeate (aohada- glycoside A, 18), β-daucosterol(19) and 3-[O-β-D-(6-O-caffeoylglucopyranosyl)]- methyl-2-en-γ-lactone (20). Compound 20 is a new one. Compounds 13, 14, 15 and 17 inhibit α-glucosidase with corresponding inhibitory rate of 61.5%, 95.5%, 72.1% and 62.6% at a concentration of 1 mg/ml, higher than acarbose. The chemical studies on Osmanthus genus and bioactivities of phenylpropanoid glycosides were summarized.

钮子瓜和袋花忍冬的化学成分研究

钮子瓜（Zehneria maysorensis Arn.）是一种常用的中草药，其性味苦、凉，主要功效为清热利湿、散风止痛，主治膀胱炎、头痛。体外活性筛选实验表明，袋花忍冬（Lonicera saccata Rehd.）95%乙醇提取物的乙酸乙酯部分对血管紧张素转化酶显示较强的抑制活性。为明确钮子瓜的药用物质基础和袋花忍冬中具有ACE抑制活性的成分，首次对两个植物的成分进行了研究。 1. 从钮子瓜95%乙醇提取物中主要通过色谱方法首次分离了14个化合物，通过波谱方法鉴定为(2S,3S,4R,10E)-2-[(2R)-2-羟基二十四烷酰基氨基]-10-十八烷-1,3,4-三醇（1）、(2S,3S,4R)-2-二十四烷酰基氨基-十八烷-1,3,4-三醇 （2）、胡萝卜苷（3）、swertish （4）、苯甲酸（5）、水杨酸（6）、loliolide （7）、胸腺嘧啶（8）、尿嘧啶（9）、(23Z)-9,19-环阿尔廷-23-烯-3β,25-二醇（10）、(20S,22E,24R)-5α,8α-表二氧-麦角甾-6,22-二烯-3β-醇（11）、十六烷酸 1-甘油酯（12）、大豆脑苷Ⅰ（13）和(22E,24S)-24-甲基-5α-胆甾-7,22-二烯-3β,5α,6β-三醇（14）。其中化合物4为一黄酮碳苷，具有旋转异构现象，有止痛作用；化合物6具有抗炎、镇痛、减热的活性，它们可能是钮子瓜药用物质基础的一部分。 2. 从袋花忍冬95%乙醇提取物中首次分离并鉴定了16个已知化合物：胡萝卜苷（3）、(20S,22E,24R)-5α,8α-表二氧-麦角甾-6,22-二烯-3β-醇（11）、十六烷酸 1-甘油酯（12）、E-p-coumaryl behenate (15)、谷甾醇（16）、2,6-dihydroxyhumula-3(12), 7(13),9(E)-triene (17)、环阿尔廷-25-烯-3β,24ξ-二醇 (18)、二十四烷酸 (19)、2,4-二羟基-3,6-二甲基苯甲酸甲酯 (20)、乌苏酸 (21)、柚皮素 (22)、木犀草素 (23)、柏双黄酮（24）咖啡酸 (25)、洋芹素（26）和木犀草素-7-O-β-D-葡萄糖苷 (27)。其中木犀草素（23）和咖啡酸（25）含量较高，它们为抑制ACE活性的成分。 3．综述了黄酮碳苷的旋转异构现象。 Zehneria maysorensis is a folk medicine for the treatment of cystitis and headache. The ethyl acetate soluble fraction of the 95% ethanol extract of Lonicera saccata showed obvious ACE inhibitory activity in vitro. To reveal their active constitutents, they were subjected to chemically study. From the 95% ethanol extract of the whole plants of Zehneria maysroensis fourteen compounds were isolated for the first time. On the basis of spectral data and/or by comparison with authentic samples, they were characterized to be (2S,3S,4R,10E)-2-[(2R)-2-hydroxytetracosanoylamino]-10-octadecene-1,3,4-triol (1), (2S,3S,4R)-2-tetracosanoylamino-1,3,4-octadecanetriol (2), daucosterol (3), swertish (4), benzoic acid (5), salicylic acid (6), loliolide (7), thymine (8), uracil (9), (23Z)-9,19-cycloart-23-ene-3β,25-diol (10), (20S,22E,24R)-5α,8α-epidioxy-ergosta- 6,22-diene-3β-ol (11), 2,3-dihydroxypropyl hexadecoate (12), soya-cerebroside (13) and (22E,24S)-24-methyl-5α-cholesta-7,22-diene-3β,5α,6β-triol (14). Compound 4, a C-glycosylflavone, showed a very interesting rotational isomerism. Compounds 4 and 6 may be the active constituents of Zehneria maysorensis considering their sedative and anti-inflammation activity, respectively. From the whole plants of Lonicera saccata, sixteen compounds were isolated for the first time. On the basis of spectral data and/or by comparison with authentic samples, they were identified to be daucosterol (3), (20S,22E,24R)-5α,8α-epidioxy- ergosta-6,22-diene-3β-ol (11), 2,3-dihydroxypropyl hexadecoate (12), E-p-coumaryl behenate (15), β-sitosterol (16), 2,6-dihydroxyhumula-3(12),7(13),9(E)-triene (17), cycloart-25-ene-3β,24ξ-diol (18), tetracosanoic acid (19), methyl 2,4-dihydroxy- 3,6-dimethylbenzoate (20), ursolic acid (21), naringenin (22), luteolin (23), cupressuflavone (24), caffeic acid (25), apigenin (26) and luteolin-7-O-β-D- glucopyranoside (27). Luteolin (23) and caffeic acid (25) were the ACE inhibitory active constituents. Rotational isomerism for C-glycosylflavonoid was reviewed.

有机质谱裂解规律及智能解析方法研究

本学位论文分为四个部分，第一部分报道了用串联质谱快速分析合成药物中的微量杂质成分以及分析中药材中的化学成分。第二部分报道了通过质谱和串联质谱发现并合成新型的PdPincer 催化剂，同时对其活性进行测试。第三部分为串联质谱自动解析软件的设计及应用。第四部分概述了应用在质谱中的各种碎裂方式。 第一部分首先总结了5-溴粉防己碱及其类似物的裂解规律，并以此为根据推测出2 个微量杂质的结构。随后针对无患子（Sapindus mukurossi Gatren.）中的皂苷成分，由ESI-QTOF 得到各个皂苷成份的高分辨质量数据进而得到其分子式，然后利用ESI-IT 电喷雾串联质谱对无患子总皂苷中各皂苷成分的结构进行进一步的鉴定。进而以同样的方式，先通过ESI-QTOF 得到黄山药（Dioscoreapanthaica���总皂苷中各个组分化合物的分子式，然后对已有的薯蓣皂苷标准品做串联质谱分析，以得到该类化合物的裂解规律并给出解析该类化合物的流程图。在此利用计算化学的方法讨论了离子的丰度与裂解活化能之间的关系。然后应用APCI-MS/MS 方法探讨了四对同分异构体和几个已知的化合物，并最后用液质联用对其进行确认，同时还给出了4 个未知化合物的可能结构。 第二部分报道通过质谱和串联质谱发现并合成新型的PdPincer 催化剂，同时对其活性进行测试。钯催化的交联反应是有机合成中C-C 键形成的最有效的方法，且硫脲是一类对空气和水都稳定的化合物，因此我们设计并合成了一系列的硫脲钯催化剂并得到了很好的催化活性。我们在对其中一类环状双硫脲化合物进行质谱实验的时候，在正离子模式下发现了反常的[M.H]+，通过串联质谱进一步确定了它是一种新型的PdPincer 结构。我们将其合成出来并通过X-ray 衍射实验确定了它的结构。同时测定其催化活性并与未形成pincer 的类似物进行比较发现该类化合物具有较宽的底物适用性。 第三部分为串联质谱自动解析软件的设计及应用。通过前面两部分的启示，独立设计开发了AuMass（1.0）。其算法是：先通过查找特殊的碎片离子，中性丢失或碎片离子质量差来确定某类化合物的骨架结构，然后利用该类化合物的自动解析流程来对其周边取代基进行确认。通过它快速地对白芍中的化学成分进行解析，并对未知的化合物进行了推测。为了增加它的解析能力，我又对其它类型的化合物裂解规律进行总结，并给出了自动解析流程。实践证明该软件具有相当好的应用价值。 第四部分综述了应用在质谱上的各类母离子的碎裂技术。这里包括了碰撞诱导裂解（CID）、光诱导碎裂（LID）、电子捕获裂解/电子转移裂解（ECD/ETD）、红外多光子解离（IRMPD）、黑体辐射解离（BIRD）和PQD 裂解技术。 This dissertation consists of four chapters. The first chapter reports the rapidanalysis of trace impurities from synthetical medicine and analysis of the chemicalconstitutents from Chinese herb medicines. The second chapter elaborates the studieson the discorvery and synthesis of new type of Pd Pincer catalyst by using MS andtandem MS together with the testing of its catalyst activity. The third chapter dwellson the designation and development of automatic tandem mass spectrometry analysissoftware. The last chapter presents a review on the dissociation technique of massspectrometry. The first chapter reports the rapid analysis of trace impurities from synthesismedicine and analysis of the chemical constitutents from Chinese herb medicines. The fission mechanism of 5-bromotetrandrine was obtained by analysis of the dissociationpathways of major product, by using which the possible structure of the two traceimpurties was assumed. There are lots of saponins in Sapindus mukurossi. Except forthe good spumescence and decontamination，it possesses the bioactivity of antigenand antitch. First of all, the high resolution mass information was obtained by ESI-QTOF. Hence the possible molecular formulars were acquired too. Then weconducted the further detection of the structures of its saponins by using ESI-ITtechnology. In the same manner, first the molecular formulars of every constituentfrom Dioscorea panthaica in total saponins were obtained by ESI-QTOF, and thenacquired the fission mechanism of this type of compounds by tandem massexperiment on a series of known and available saponins. In the same time, theanalysis flowchart was concluded. Here the relationship between the ion intensity andthe corresponding dissiociation activation energy was studied by computer chemistry.Then the four pairs of isomers were differentiated by APCI-MS/MS, as well as thecharacterization of known and unknown compounds. The assumption was confirmed by HPLC-MS/MS. Among them the possible structures of four unknown saponinswas presented. The second part was discovery and synthesis of a new type of Pd pincer catalystby MS and tandem MS. The coupling reaction catalyzed by Pd is the most effectivemethod in C-C formation in organic synthesis. Apart from that, thiourea is type ofcompounds that are stable to atmosphere and moisture. Hence we designed a series ofPd thiourea catalysts. Some of them show the excellent catalyst activity. The abnormalparent ion [M.H]+ was founded in positive ESI mode when we conduct some massspectrometry experiments on the bicyclical thiourea Pd complex. The structure wasproposed by mass and tandem mass spectrometry. Because it was a new type of pincer,we want to test its catalyst activity. So the Pd pincer was synthesized and the detailstructure was obtained by x-ray experiment. It shows the more fitness in catalysis ofSuzuki reaction by comparison with the analogue. The third chapter dwells on the design and development of automatic tandemmass spectrometry analysis software. Inspired by the former two chapters, theAuMass (version 1.0) was developed. Its algorithm is: first check the diagnostic ion,diagnostic neutral loss or diagnostic ions mass intervals in database to find out whatthe analyst’s skeleton belongs to, then identify the peripheral functional group by thecorresponding analysis flowchart. The chemical constituents of Paeonia lactiflorawere identified rapidly by using AuMass. To increase the analysis ability, the othertypes of compounds from Chinese herbs was concluded. Actually, the software isproven to have the much valuable application. The last chapter presented the review on the some kinds of fission technique ofmass spectrometry. It involves the collision induced dissociation (CID), laser induceddissociation (LID), electron capture dissociation/electron transfer dissociation(ECD/ETD), infrared multiple photons dissiociation, black body irraditiondissociation and PQD fission technique from Finnigan.

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.

中国沙棘(Hippophae rhamnoides subsp. sinensis)天然群体的遗传变异分析

近十年，植物群体遗传学的研究飞速发展，然而与海拔相关的植物群体遗传结构和遗传变异研究却相对较少。到目前为止，还不清楚遗传变异与海拔之间是否有一个通用的格局。在山区，各种生态因子，如温度、降水、降雪、紫外线辐射强度以及土壤成分都随海拔梯度急剧变化，造成了即使在一个小的空间区域，植被类型变化显著，这种高山环境的异质性和复杂性为我们研究植物群体遗传结构和分化提供了方便。沙棘(Hippophea)属于胡颓子科(Elaeagnaceae)为多年生落叶灌木或乔木，雌雄异株，天然种群分布极为广泛。中国沙棘(H. rhamnoides subsp. sinensis)是沙棘属植物中分布较广的一个亚种，种内形态变异非常丰富，加之其具有独特的繁育系统和广泛的生态地理分布，是研究沙棘属植物遗传变异和系统分化的理想材料。本文从1,800 m 到3,400 m 分5 个海拔梯度进行取样，用RAPD 和cpSSR 分子标记研究了卧龙自然保护区中国沙棘天然群体的遗传结构和遗传变异。5 个取样群体依次标记为A、B、C、D 和E，它们分别代表分布在海拔1,800，2,200，2,600，3,000 和3,400 m 的5 个天然群体。RAPD实验用11 条寡核苷酸引物，扩增得到151 个重复性好的位点，其中143 个多态位点，多态率达94.7%。在5 个沙棘群体中，总遗传多样性值(HT)为0.289，B群体内的遗传多样性值为0.315，这完全符合沙棘这种多年生、远交的木本植物具有高遗传变异的特性。5 个群体内遗传多样性随海拔升高呈低－高－低变异趋势，在2,200 m海拔处的B群体遗传多样性达最大值0.315，3,400 m海拔处的E群体则表现最小仅0.098。5 个群体间的遗传分化值GST＝0.406，也即是说有40.6%的遗传变异存在于群体间，1,800 m海拔处的A群体与其它群体的明显分离是造成群体间遗传分化大的原因。UPGMA聚类图和PCoA散点图进一步确证了5 个群体间的关系和所有个体间的关系。最后，经过Mantel检测，遗传距离与海拔表现了明显的相关性(r = 0.646, P = 0.011)。cpSSR 实验中，经过对24 对cpSSR 通用引物筛选，11 对引物能扩增出特异性条带，只有2 对引物(ccmp2 和ARCP4)呈现多态性。4 个等位基因共组合出4 种单倍型，单倍型Ⅰ出现在A 群体的所有个体和B 群体的8 个个体中，C、D、E 三个群体均不含有，而单倍型Ⅱ出现在C、D、E 三个群体的所有个体及B 群体的18 个个体中，A 群体不含有。另外两种单倍型Ⅲ和Ⅳ为稀有类型，仅B 群体中的4 个个体拥有。这种单倍型分布模式和TFPGA 群体聚类图揭示了，C、D、E 群体可能来源于同一祖先种，而A 群体却是由另一祖先种发展起来的，B 群体则兼具了这两种起源种的信息，这可能是因为在历史上的某一时期，在中国沙棘群体高山分化的过程中，B 群体处某个或者某些个体发生了基因突变，具备了适应高海拔环境的能力，产生了高海拔沙棘群体的祖先种。 In recent ten years, studies about population genetics of plants developed rapidly,whereas their genetic structure and genetic variation along altitudinal gradients have beenstudied relatively little. So far, it is uncleared whether there is a common pattern betweengenetic variation and altitudinal gradients. In the mountain environments, importantecological factors, e.g., temperature, rainfall, snowfall, ultraviolet radiation and soil substratesetc., change rapidly with altitudes, which cause the vegetation distribution varying typically,even on a small spatial scale. The mountain environments, which are heterogeneous andcomplex, facilitate and offer a good opportunity to characterize population genetic structureand population differentiation.The species of the genus Hippophae L. (Elaeagnaceae) are perennial deciduous shrubs ortrees, which are dioecious, wind-pollinated pioneer plants. The natural genus has a widedistribution extending from Northern Europe through Central Europe and Central Asia toChina. According to the latest taxonomy, the genus Hippophae is divided into six species and12 subspecies. The subspecies H. rhamnoides ssp. sinensis shows significant morphologicalvariations, large geographic range and dominantly outcrossing mating system. Thesecharacteristics of the subspecies are favourable to elucidate genetic variation and systemevolution. To estimate genetic variation and genetic structure of H. rhamnoides ssp. sinensisat different altitudes, we surveyed five natural populations in the Wolong Natural Reserve at altitudes ranging from 1,800 to 3,400 m above sea level (a.s.l.) using random amplifiedpolymorphic DNA markers (RAPDs) and cpSSR molecular methods. The five populations A,B, C, D, and E correspond to the altitudes 1,800, 2,200, 2,600, 3,000 and 3,400 m,respectively.Based on 11 decamer primers, a total of 151 reproducible DNA loci were yielded, ofwhich 143 were polymorphic and the percentage of polymorphic loci equaled 94.7%. Amongthe five populations investigated, the total gene diversity (HT) and gene diversity within population B equaled 0.289 and 0.315, respectively, which are modest for a subspecies of H.rhamnoides, which is an outcrossing, long-lived, woody plant. The amount of geneticvariation within populations varied from 0.098 within population E (3,400 m a.s.l.) to 0.315within population B (2,200 m a.s.l.). The coefficient of gene differentiation (GST) amongpopulations equaled 0.406 and revealed that 40.6% of the genetic variance existed amongpopulations and 59.4% within populations. The population A (1,800 m a.s.l.) differed greatlyfrom the other four populations, which contributes to high genetic differentiation. A UPGMAcluster analysis and principal coordinate analyses based on Nei's genetic distances furthercorroborated the relationships among the five populations and all the sampling individuals,respectively. Mantel tests detected a significant correlation between genetic distances andaltitudinal gradients (r = 0.646, P = 0.011).Eleven of the original 24 cpSSR primer pairs tested produced good PCR products, onlytwo (ccmp2 and ARCP4) of which were polymorphic. Four total length variants (alleles) werecombined resulting in 4 haplotypes. The haplotype was present in all individuals of Ⅰpopulation A and 8 individuals of populations B, the other three populations (C, D and Epopulations) did not share. The haplotype was present in all individuals of populations C, D Ⅱand E and 18 individuals of populations B, population A did not share. The other twohaplotypes and were rare haplotypes, which were only shared in 4 individuals of Ⅲ Ⅳpopulation B. The distribution of haplotypes and TFPGA population clustering map showedthat the populations C, D and E might be origined from one ancestor seed and population Amight be from another, whereas population B owned information of the two ancestor seeds. Itwas because that gene mutation within some individual or seed in the location of population Bwas likely to happen in the history of H. rhamnoides, which was the original ancestor of thehigh-altitude populations.

干旱胁迫与施N条件下白刺花（Sophora davidii）幼苗生长及其适应机制

干旱环境常常由于多变的降水事件和贫瘠土壤的综合作用，表现出较低的生产力和较低的植被覆盖度。全球性的气候变暖和人类干扰必将使得干旱地区缺水现状越来越严竣。贫瘠土壤环境中已经很低的有效养分含量也将会随着干旱的扩大而越来越低。干旱与半干旱系统中不断加剧的水分与养分的缺失将严重限制植物的生长和植被的更新，必然会使得已经恶化的环境恶化速率的加快、恶化范围的加大。如何抑制这种趋势，逐步改善已经恶化的环境是现在和将来干旱系统管理者面临的主要关键问题。了解干旱系统本土植物对未来气候变化的适应机制，不仅是植物生态学研究的重要内容，也对人为调节干旱环境，改善干旱系统植被条件，提高植被覆盖度具有重要的实践意义。 本研究以干旱河谷优势灌木白刺花（Sophora davidii）为研究对象，通过两年大棚水分和施N控制实验和一个生长季野外施N半控制实验，从植物生长－生理－资源利用以及植物生长土壤环境特征入手，系统的研究了白刺花幼苗生长特性对干旱胁迫和施N的响应与适应机制，并试图探讨施N是否可调节干旱系统土壤环境，人工促进干旱条件下幼苗定居，最终贡献于促进植被更新实践。初步研究结论如下： 1）白刺花幼苗生长、生物量积累与分配以及水分利用效率对干旱胁迫和施N处理的适应白刺花幼苗株高、基径、叶片数目、叶面积、根长、生物量生产、相对含水量和水分利用效率随着干旱胁迫程度的增加而明显降低，但地下部分生物量比例和R/S随着干旱胁迫程度的增加而增加。轻度施N处理下幼苗株高、基径、叶片数目、叶片面积和生物量生产有所增加。但重度施N处理下这些生长指标表现出微弱甚至降低的趋势。严重干旱胁迫条件下，幼苗叶面积率、R/S、相对含水量和水分利用效率也以轻度施N处理为最高。 2）白刺花幼苗叶片光合生理特征对干旱胁迫和施N处理的适应叶片光合色素含量和叶片光合效率随着干旱胁迫程度的增加而显著降低，并且PS2系统在干旱胁迫条件下表现出一定程度的光损害。但是比叶面积随着干旱胁迫程度的增加而增加。在相对较好水分条件下幼苗净光合速率的降低可能是因为气孔限制作用，而严重干旱胁迫条件下非气孔限制可能是导致幼苗叶片光合速率下降的主要原因。叶片叶绿素含量、潜在光合能力、羧化效率、光合效率以及RUBP再生能力等在施N处理下得到提高，并因而改善干旱胁迫条件下光合能力和效率。虽然各荧光参数对施N处理并无显著的反应，但是干旱胁迫条件下qN和Fv/Fm在轻度施N处理下维持相对较高的水平，而两年连续处理后在严重干旱胁迫条件下幼苗叶片光合效率受到重度施N处理的抑制，并且Fv/Fm和qN也在重度施N处理下降低。 3）白刺花幼苗C、N和P积累以及N、P利用效率对干旱胁迫和施N处理的适应白刺花幼苗C、N和P的积累，P利用效率以及N和P吸收效率随干旱胁迫程度的增加而显著降低，C、N和P的分配格局也随之改变。在相同水分处理下，C、N和P的积累量、P利用效率以及N和P吸收效率在轻度施N处理下表现为较高的水平。然而，C、N和P的积累量和P利用效率在重度施N处理下不仅没有表现出显著的正效应，而且有降低的趋势。另外，在相同水分条件下白刺花幼苗N利用效率随着施N强度的增加而降低。 4）白刺花幼苗生长土壤化学与微生物特性对干旱胁迫和施N的适应白刺花幼苗生长土壤有机C、有效N和P含量也随干旱胁迫程度的增加而明显降低。干旱胁迫条件下土壤C/N、C/P、转化酶、脲酶和碱性磷酸酶活性的降低可能表明较低的N和P矿化速率。尽管微生物生物量C、N和P对一个生长季干旱胁迫处理无显著反应，但微生物生物量C和N在两年连续干旱胁迫后显著降低。土壤有机C和有效P含量在轻度施N处理下大于重度施N处理，但是有效N含量随着施N强度的增加而增加。微生物生物量C和N、碱性磷酸酶和转化酶活性也在轻度施N处理下有所增加。但是碱性磷酸酶活性在重度施N处理下降低。 5）野外条件下白刺花幼苗生长特征及生长土壤生化特性对施N的适应植物生长、生物生产量、C的固定、N、P等资源的吸收和积累、其它受限资源的利用效率（如P）在轻度施N处理下均有所增加，但N利用效率有所降低。幼苗生物生产量及C、N和P等资源的分配格局在轻度施N处理下也没有明显的改变。白刺花幼苗叶片数目、生物生产量和C、N、P的积累量在重度施N处理下虽然也相对于对照有所增加，但幼苗根系长度显著降低。生物量及资源（生物量、C、N、P）在重度施N处理下较多地分配给地上部分（主要是叶片）。另外，土壤有机C、全N和有效N含量随外源施N的增加而显著增加，土壤pH随之降低，但土壤全P含量并无显著反应。其中有机C含量和有效P含量以轻度施N处理最高。微生物生物量C、N和P在轻度施N处理下也显著增加，而微生物生物量C在重度施N处理下显著降低。同时，转化酶、脲酶、碱性磷酸酶和中性磷酸酶活性在施N处理下也明显的提高，但酸性磷酸酶和过氧化氢酶活性显著降低，其中碱性磷酸酶和中性磷酸酶活性以轻度施N处理最高。 综合分析表明，干旱河谷水分和N严重限制了白刺花幼苗的生长。施N不能完全改变干旱胁迫对白刺花幼苗的抑制的作用，但是由于施N增加土壤N有效性，改善土壤一系列生物与化学过程，幼苗的生长特性也对施N表现出强烈的反应，表现为植物结构与资源分配格局的改善，植物叶片光合能力与效率的提高，植物生长以及利用其他受限资源（如水分和P）的效率的增加，致使植物自身生长及其生长环境在干旱环境下得到改善。但是过度施N不仅不能起到改善干旱胁迫下植物生长环境、促进植物生长的作用，反而在土壤过程以及植物生长过程中加重干旱胁迫对植物的伤害。因此，建议在采用白刺花作为先锋种改善干旱河谷系统环境的实践中，可适当施加N以改善土壤环境，调节植物利用与分配资源的效率，促进植物定居，得到人工促进种群更新的目的。但在实践过程中也要避免过度施N。 Arid regions of the world are generally noted for their low primary productivity which is due to a combination of low, unpredictable water supply and low soil nutrient concentrations. The most serious effects of global climate change and human disturbances may well be those which related to increasing drought since drought stress has already been the principal constraint in plant growth. The decline in total rainfall and/or soil water availability expected for the next decades may turn out to be even more drastic under future warmer conditions. Nevertheless, water deficit is not the only limiting factor in arid and semiarid environments. Soils often suffer from nutrient (especially N and P) deficiencies in these ecosystems, which can also be worsened by climate change. How to improve the poor soil quality and enhance the vegetation coverage is always the problem facing ecosystem managers. The adaptive mechanisms of native plant to future climate change is always the focus in plant ecology, it also plays important roles in improving vegetation coverage by manual controlled programmes. Sophora davidii is a native perennial shrub of arid valleys, which is often predominant on eroded slopes and plays a vital role in retaining ecological stability in this region. It has been found that S. davidii was better adapted to dry environment than other shrubs, prompting its use for re-vegetation of arid lands. A two-years greenhouse experiment and a field experiment were conducted in order to understand the adaptation responses of Sophora davidii seedlings to different water and N conditions, and further explore if additional N supply as a modified role could enhance the adaptation ability of S. davidii seedlings to dry and infertile environment. Two-month old seedlings were subjected to a completely randome design with three water (80%, 40% and 20% water field capacity (FC)) and three N supply (N0: 0, Nl: 92 and Nh: 184 mg N kg-1 soil) regimes. Field experiment was arranged only by three N supplies in the dry valley. 1) The growth, biomass partitioning and water-use efficiency of Sophora davidii seedlings in respond to drought stress and N supply Seedlings height, basal diameter, leaf number, leaf area, root length, biomass production, relative water content (RWC) and WUE were decreased with increase of drought stress. An increase in below-ground biomass was observed indicating a higher root/shoot ratio (R/S) under drought stress conditions. Low N supply increased seedlings height, basal diameter, leaf number, leaf area, and biomass production, but decreased root length. In contrast, these growth characteristics showed little or negative effect to high N supply treatment. Leaf percentages increased with increase of N supply, but fine root percentages decreased. In addition, Low N supply rather than the other two N treatments increased leaf area ratio (LAR), leaf/fine root mass ratio (L/FR), R/S and RWC under severe drought stress (20%FC), even though these parameters could increase with the high N supply treatment under well-watered condition (80%FC). Moreover, Low N supply also increased WUE under three water conditions, but high N supply had little effect on WUE under drought stress conditions (40%FC and 20%FC). 2) Leaf gas exchange and fluorescence parameters of Sophora davidii seedlings in respond to drought stress and N supply Leaf area (LA), photosynthetic pigment contents, and photosynthetic efficiency were decreased with increase of drought stress, but specific leaf area (SLA) increased. Photodamage in photosystem 2 (PS2) was also observed under drought stress condition. The decreased net photosynthetic rate (PN) under relative well-watered water conditions might result from stomatal limitations, but the decreased PN under other hand, photosynthetic capacity by increasing LA, photosynthetic chlorophyll contents, Pnmax, CE, Jmax were increased with increase N supply, and photosynthetic efficiency was improved with N supply treatment under water deficit. Although N supply did a little in alleviating photodamages to PS2 caused by drought stress, low N supply enhanced qN and kept relative high Fv/Fm under drought stress condition. However, high N supply inhibited leaf photosynthetic efficiency, and declined Fv/Fm and qN under severe drought stress condition after two year continues drought stress and N supply. 3) Carbon accumulation, nitrogen and phosphorus use efficiency of Sophora davidii seedlings in respond to drought stress and N supply C, N and P accumulation, NUE , N and P uptake efficiency (NUtE and NUtE ) P N P were decreased with increase of drought stress regardless of N supply. On the other hand, the S. davidii seedlings exhibited strong responses to N supply, but the responses were inconsistent with the various N supply levels. Low N supply rather than the other two N treatments increased C, N and P accumulation, improved NUEP, NUtE and NUtE under corresponding water condition. In contrast, high N supply N P did few even depressed effects on C, N and P accumulation, and NUEP, although NUtEN and NUtEP could increase with high N supply under corresponding water conditions. Even so, a decrease of NUEN was observed with increase of N supply under corresponding water conditions. 4) Soil microbial and chemical characters in respond to drought stress and N supply The content of soil organic C, available N and P were decreased with increase of drought stress. Decreases in C/N and C/P, and invertase, urea and alkaline phosphatase activity were also observed under drought stress conditions, indicating a lower N and P mineralization rate. Although microbial biomass C, N and P showed slight responses to drought stress after one growth period treatment, microbial biomass C and N were also decreased with increase of drought stress after two year continuous treatment. The content of soil organic C and available P showed the stronger positive responses to low N supply than which to high N supply, although than the other two N treatments increased microbial biomass N and invertase activity under severe drought stress condition, even though invertase activity could increase with high N supply treatment under relative well-water conditions. Moreover, low N supply treatment also increased C/P and alkaline phosphatase activity which might result from higher P mineralization, but high N supply did negative effects on alkaline phosphatase activity. 5) The growth characteristics of Sophora davidii seedlings and soil microbial and chemical characters in respond to N supply under field condition Low N supply facilitated seedlings growth by increasing leaf number, basal diameter, root length, biomass production, C, N and P accumulation and absorption, and enhancing the use efficiency of other limited resources as P. Compared to control, however, low N supply did little effect on altering biomass, C, N and P portioning in seedlings components. On the contrary, high N supply treatment also increased leaf number, biomass and C, N and P accumulation relative to control, but significantly decreased root length, and altered more biomass and resources to above-ground, which strongly reduced the ability of absorbing water under drought condition, and thus which might deep the drought stress. In addition, N supply increased soil C, N and available N content, but declined pH and showed little effects on P content. Low N supply showed higher values of soil C and available P content. Low N supply also increased microbial biomass C, N and P, although high N supply decreased microbial biomass C. N supply significantly enhanced soil invertase, urea, alkaline and neutral phosphratase activity, while declined acid phosphratase and catalase activity. Low N supply exhibited higher alkaline and neutral phosphratase activity compared to the others. The results from this study indicated that both drought and N limited the growth of S. davidii seedlings and their biomass production. Regardless of N supply levels, drought stress dramatically reduced the seedlings growth and biomass production. Although plant growth parameters, including basal diameter, height, leaf number, and biomass and their components were observed to be positive responses to low N supply, N supply alone can not alter the diminishing tendency which is caused by drought. available N content increased with increase N supply. In addition, low N supply rather These findings imply that drought played a primary limitation role and N was only the secondary. Even so, appropriate N supply was seemed to enhance the ability that S. davidii seedlings adapted to the xeric and infertile environment by improving soil processes, stimulating plant growth, increasing recourses accumulation, enhancing use efficiency of other limited resources, and balancing biomass and resources partitioning. Appropriate N supply, therefore, would be recommended to improve S. davidii seedling establishment in this region, but excess N supply should be avoided.

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.

角蟾科（Megophryidae; Anura）蝌蚪的形态多样性和生态适应

角蟾科（Megophryidae）是以角蟾属（Megophrys Kuhl and Van Hasselt, 1822）为模式属而建立的，隶于无尾目（Anura），变凹型亚目（Anomocoela）。角蟾科包括2 亚科11 属142 种，分布于东洋界，从巴基斯坦、中国西部向东直到菲律宾和苏达群岛；中国有9 属75 种分布于华中和华南地区。角蟾科被认为是原始的两栖动物之一，其分类学、系统学、生态学、动物地理学的研究均深受中外科学家的瞩目。近年来，通过形态学、古生物学、细胞学、生态学、支序系统学的研究，角蟾科的分类与系统学研究取得了较大进展。与成体形态和分子系统学研究结果相比较，蝌蚪的研究存在更多的问题和挑战，尚需深入研究：（1）角蟾科蝌蚪的形态多样性分析；（2）角蟾科的系统发育关系与蝌蚪的演化，以及口漏斗的起源；（3）角蟾科蝌蚪表型分化与栖息环境和觅食行为的适应演化。针对上述问题，本文对角蟾科9 属30 种蝌蚪的形态特征，包括外部宏观形态和口器外部结构特征、口器内部显微结构、唇齿和角质颌的亚显微结构作了深入细致、多层次的比较研究；通过12s rRNA 和cytochrome b 基因构建最大简约树，采用贝叶斯系统发育进行分析，蝌蚪型的演化采用祖先性状的重建方法分析；得到如下结论：1）初步将角蟾科蝌蚪分为4 种类型；并且建立了2 种新的角蟾科蝌蚪类型。A 型：拟髭蟾型蝌蚪，该型蝌蚪包括拟髭蟾属、髭蟾属、齿蟾属和齿突蟾属的物种；B 型：新类型，掌突蟾型蝌蚪，该型蝌蚪在本文中包括掌突蟾属、小臂蟾属的物种；C 型：新类型，短腿蟾型蝌蚪，一种特化类型，该型蝌蚪在本文中仅包括短腿蟾属的物种；D 型：角蟾型蝌蚪，该型蝌蚪在本文中包括无耳蟾属、小口拟角蟾属和异角蟾属的物种。2）对角蟾科的分类进行了修订：（1）支持角蟾科两个亚科的分类系统；（2）角蟾亚科包括拟角蟾属、异角蟾属、无耳蟾属和短腿蟾属；该亚科形态差异小，系统学关系比较复杂，暂不作族级分类的再划分；（3）拟髭蟾亚科分为2 个族：拟髭蟾族，该族物种具有类型A 的蝌蚪，包括4 个属：拟髭蟾属、髭蟾属、齿蟾属、齿突蟾属；掌突蟾族，该族物种具有类型B 的蝌蚪，包括2 个属：掌突蟾属和小臂蟾属。3）结合分子系统进化关系探讨了4 种蝌蚪类型的演化。（1）角蟾科蝌蚪的最近共同祖先来自于一类具有拟髭蟾型蝌蚪性状的蝌蚪；（2）掌突蟾型蝌蚪和角蟾亚科的蝌蚪是由具有拟髭蟾型蝌蚪性状的祖先蝌蚪分别演化而来；（3）短腿蟾型蝌蚪是角蟾型蝌蚪的一种特化类型；（4）外群蝌蚪具有与拟髭蟾型蝌蚪相似的性状，进一步印证了类拟髭蟾型蝌蚪是角蟾科蝌蚪的最近共同祖先的假说；（5）具有口漏斗的蝌蚪类型是由不具口漏斗的蝌蚪类型演化而来，在角蟾科中口漏斗是一种衍生性状。4）分析了角蟾科四种蝌蚪类型与栖息环境的适应演化。（1）角蟾科蝌蚪的口部和体形的变化反映了该科蝌蚪由缓流向类似静水生境的回水凼的渐变式适应，角蟾科蝌蚪的形态显示了多方面的适应变化；（2）随着蝌蚪类型由A 向D的演化，当水速较大时，拟髭蟾型的蝌蚪营流水攀吸型生活方式；当水速递减时，掌突蟾型蝌蚪营流水附着型生活方式；当水速进一步递减时，具有较小口漏斗的短腿蟾型蝌蚪和具有大漏斗的角蟾型蝌蚪营流水浮泳型生活。角蟾科蝌蚪对于水流递减的适应演化说明蝌蚪的生态学适应是具有进化意义的；（3）蝌蚪口器内部结构的分化揭示了蝌蚪和食性的适应关系，蝌蚪以口部的唇齿与角质颌刮取或吞吸水中的物质，然后，通过口乳突有选择地过滤进入口腔中食物。拟髭蟾亚科蝌蚪的唇齿多而窄，唇齿间距宽，颌鞘粗而稀，反映了其植食性为主的特点；它们的舌前乳突一般为指状，在口腔入口处所占面积小，其机械过滤的作用很多被唇齿和角质颌分担了；而角蟾亚科的蝌蚪，其角质颌弱，其舌前乳突一般为匙状，几乎填满了口腔入口处，因此舌前乳突起了主要的机械过滤作用。The family Megophryidae is the largest and most diverse families inArchaeobatrachia, and most of its species occur in India, Pakistan, and eastward intoChina, Southeast Asia, Borneo and the Philippines to the Sunda Islands. Currently thefamily includes 142 species have been grouped into two subfamilies, Megophryinaeand Leptobrachiinae. The mountains of central and southern China are rich in speciesof Megophryidae, 75 species belong to 9 genera and two subfamilies.The family was supposed to be ideal materials of studies in many fields of biology,such as taxonomy, evolution, systematics, ecology, and biogeography. Recently, therehave a great development in taxonomy and systematics of megophryids throughstudied by morphology, paleontology, cytology, ecology, and cladistics. However,larvae of megophryids were generally unknown, although the tadpoles might be veryimportant for above studies.In this paper, we examined the evolutionary scenario of the tadpoles’ morphologyin the context of a phylogenetic framework. Our objectives are (1) to evaluate thedivergence of larval body shape and oral discs in the family Megophryidae, (2) toexplore the evolutionary trends of the larvae in megophryidae, and test if thefunnel-shaped oral disc is apomorphic, and (3) to explore the relationship of the larvalstructure, diet and microhabitat.We examined larval morphology of 30 megophryid species, the larval body shape,oral discs, the buccopharyngeal cavity, and jaw sheaths and denticles of the Chinesemegophryid frogs were re-examined. We constructed a phylogeny of the species on thebasis of published mitochondrial cytochrome b and 16S rRNA gene segments usingpartitioned Bayesian analyses. Furthermore, hypothetical changes of larval morphologywere inferred using parsimony principle on the phylogeny. The results showed that:1) Four tadpole types in Megophryidae. The larval morphological charactersseries in Chinese megophryids fall into four general categories according to the bodyshape and oral discs: (A) Leptobrachiini type, species from genera Leptobrachium,Oreolalax, Scutiger and, Vibrissaphora share this type of tadpoles. (B) Leptolalax type,species of genus Leptolalax have this type of tadpoles. (C) Brachytarsophrys type,species of the genus Brachytarsophrys have this type of tadpoles. (D) Megophryinitype, species of the genera Atympanophrys, Ophryophryne, and Xenophrys share this type of tadpoles. Of which B and C are two novel types.2）Taxonomic implications. The present study leads us to reconsider the generalclassification of tribes attributed to members of Megophryidae. More specifically,concerning the phylogenetic relationships and the two novel tadpole types describedherein, we propose a provisional taxonomy for the family but suggest that further taxasampling of other megophryids be performed to confirm this taxonomic change. TheMegophryidae is composed of two subfamilies (Leptobrachiinae and Megophryinae).The Leptobrachiinae was recogonized the two tribes: (1) tribe Leptobrachiini sensuDubois, corresponding to the tadpole of type A, including four genera, i.e.,Leptobrachium, Oreolalax, Scutiger and, Vibrissaphora; (2) tribe Leptolalaxini,corresponding to the tadpole of novel type B, including two genera, i.e., Leptolalaxand Leptobrachella. However, the relationships among the genera of Megophryinaewere largely unresolved, they recognized no monophyletic groups above the generalevel. A more thorough sampling will likely foster a better taxonomic solution.3) The larval evolutionary scenario in Megophryidae.Type A is characteristicof normal-mouthed with multiple tooth rows, representing the tadpole type of theMRCA of Chinese megophryids. Type B is characteristic of normal-mouthed withreduced tooth rows, prolonging labium, and integumetary glands. Type C ischaracteristic of no labial teeth and smaller umbeliform oral disc. Type D ischaracteristic of no labial teeth, enlarged umbeliform oral disc, representing the tadpoleof the MRCA of subfamily Megophryinae. A previous hypothesis, referring tofunnel-shaped oral discs as an apomorphy, is supported.4) The larval adaptation to habitats in Megophryidae. Tadpoles generallyadhere to substrates using their mouths, and the microhabitat that the tadpoles occupyreflects the degree of adhesion and oral complexity. The morphological changes inmegophryid tadpoles virtually allow a progressive adaptation to a changing habitatfrom faster water to slower water. Within the tadpoles of Type A to type D, the TOTbecomes smaller and smaller, and the oral disc orientates from anteroventral toumbelliform upturned, and eye position orientates from dorsal to lateral, and the trunkis more and more depressed and tail becomes relatively longer and slender. Within therunning water, the normal-mouthed with multiple tooth rows of Leptobrachiini tadpoles are correlated with lotic-suctorial, benthic feeders with anteroventral oraldisc and the largest body. With the water’s velocity decreasing, the lotic-adherentfeeders of Leptolalax tadpoles have tube-shaped labium with reduced tooth rows andintegumetary glands. And then, the smaller umbeliform in Brachytarsophrys tadpolesand the enlarged umbeliform oral disc in the Megophryini tadpoles are inhabitmicrohabitats of non-flowing backwaters of rivers, indicative of adaptive traits oflotic-neustonic surface feeders. The scheme of megophryid tadpoles andmicrohabitats provided the first clear evidence which congruent with the hypothesis ofAltig and Johnston (1989). The ecological divergence plays a general role in thedivergence and evolution of megophrid larvae. There is a definite correlation amongthe buccopharyngeal cavity, diet and feeding mechanisms, the tadpole graze orswallow the food particles, then through papillae which like a sieve and sort out foodparticles to the oesophagus. The tadpole of Leptobrachiinae possess multiple toothrows, wide intertooth distance as well as thick and sparse jaw sheath, these tadpolesinhabit bottom of the streams and graze on epiphyton or major detritus of organicmatter on the substrates, their prelingual papillae like single finger, the mechanicalpurpose of papillae served share in by tooth and jaw. The tadpoles of Megophryinaeoccur near the water surface of small streams and are the filter feeder, their dietincludes plankton and organic debris floating on the water surface, those tadpolepossess weak jaw, their prelingual papillae like spoon, the mechanical purpose ofpapillae served mostly for sieve.

链霉菌S227抗耐药菌活性成分的研究

本论文以从四川峨嵋山森林土壤中分离筛选获得的一株产抗耐药性活性化合物的链霉菌S227为材料，对发酵液中活性物质的分离纯化及抗耐药性活性进行了研究。 建立了抗耐药性活性的定性、定量检测方法。建立的管蝶法活性定量检测的标准回归方程为：D=4.8229Ln(C)+3.6326 R=0.9972 ；纸片法活性定量检测的标准回归方程为：D=5.5Ln(C)-12.794 R=0.999。 根据建立的样品活性的检测方法，测定了发酵液的初始活性。实验证明活性物质的温度、pH稳定性好。 通过活性的定性、定量追踪方法，分别利用等体积的石油醚、乙酸乙酯、正丁醇在不同的pH梯度下萃取，确定了pH3条件下正丁醇能最大程度的萃取活性物质，说明活性物质极性很大。对正丁醇萃取相经过两次硅胶柱层析及薄层层析分离得到具有抗耐药菌活性的纯化样品S227-4。 经过核磁共振氢谱、碳谱数据分析初步确定S227-4为四聚糖，通过糖的水解实验初步确定S227-4由葡萄糖和半乳糖组成。 纸片法活性检测表明S227-4具有抗耐药菌活性。采用MIC测定法对该样品抗耐药活性进行研究。在证明该样品本身不具有抗菌活性的基础上，以临床分离的耐药性金黄色葡萄球菌为指示菌，考察了该样品与抗生素联合使用时对耐药菌抗生素MIC（最小抑菌浓度）值的影响，结果表明在不影响菌体生长的浓度条件下，该样品能明显降低多株耐药菌对多种抗生素的MIC值，不同程度地恢复所测试耐药菌对相应抗生素的敏感性。如S227-4与青霉素钠联用可以使S. aureus 12352的MIC降低8倍，而与红霉素联用可以使S. aureus 12334的MIC降低128倍。 The purification process and the activity of the anti bacterial drug resistance compounds produced by Streptomyces S227 isolated from the forest soil sample of the Mountain E’MEI in Sichuan Province were studied in this thesis. Quantitative and qualitative activity assay methods of the active compounds were established. The regression equation of the tube method was D=4.8229Ln(C)+3.6326, R=0.9972. The regression equation of the paper method was D=5.5Ln(C)-12.794, R=0.999. According to the established activity assay method, the incipient activity of the broth was evaluated. And it was proved that the stability of the active compounds was good. By quantitative and qualitative activity tracing method, petroleum ether, ethyl acetate and butanol were used to extract the active compounds at different pH. The result showed that butanol was the most effective agent for active component recovery at pH3. From the butanol extraction a purified sample, S227-4, was isolated by silica gel column chromatography and thin-layer chromatography . S227-4 was proved to be a tetra- saccharide by 1H-NMR and 13C-NMR. And its monosaccharides include glucose and galactose by hydrolysate analysis. The anti-drug resistant activity of S227-4 was tested in vitro by MICs assay using different drug resistant Staphylococcus aureus strains isolated clinically. The sample itself showed no anti-microbial activity in growth inhibitory experiment, but when it was used together with different antibiotics, it could remarkably decrease the MICs of different clinically isolated drug-resistant bacterial strains to these antibiotics. For example, when S227-4 was used with penicillin, the MIC of S. aureus 12352 decreased 8 times compared with that when penicillin was used alone. Meanwhile when it was used with erythromycin the MIC of S. aureus 12334 deceased 128 times compared with erythromycin alone.

Non-commutative oscillator with Kepler-type dynamical symmetry

A 3-dimensional non-commutative oscillator with no mass term but with an appropriate momentum-dependent potential admits a conserved Runge-Lenz vector, derived from the dual description in momentum space. The trajectories lie on ellipses. The dynamical symmetry allows for an algebraic determination of the bound-state spectrum and extends to o(4,2). (c) 2010 Elsevier B.V. All rights reserved.