牦牛的分类学地位及起源研究:mtDNA D-loop序列的分析

牦牛的起源与属级分类学地位至今仍然存在一定的争议.我们测定了家养牦牛和野生牦牛线粒体控制区(D-loop)序列,并以此构建牦牛和牛属、野牛属、水牛属以及非洲水牛属相关种的系统发育树.研究结果表明线粒体D-loop区与Cyt b基因序列在构建牛族的系统发育具有同样重要的价值.系统发育关系显示野牛属的灭绝种草原野牛与现存种美洲野牛先聚合为一单系群,然后再和牦牛形成一单系分支,表明牦牛与野牛属的草原野牛、美洲野牛亲缘关系最近,具有最近的共同祖先,而与牛属的其它亚洲物种亲缘关系较远.因此,本研究不支持将牦牛独立为牦牛属--Poephagus,牛属与野牛属在分类上也应合并为一个属.基于上述研究结果和化石证据,我们进一步对牦牛起源的历史背景进行了讨论,认为牦牛与野牛属的分化是由于第四纪气候变化在欧亚大陆发生的,野牛通过白令陆桥进入北美;冰期结束后,由于欧亚大陆其它地区温度升高,牦牛只能局限分布在较为寒冷的青藏高原;而野牛属在北美先后分化为草原野牛和美洲野牛,前者可能是后者的直接祖先.

唐古特大黄乙醇提取物的HPLC指纹图谱研究

用高效液相色谱法建立唐古特大黄乙醇提取物的指纹图谱分析方法.采用Phenomenex Kromasil C_(18)色谱柱(4.6mm×250mm, 5μm);甲醇 - 0.1% H_3PO_4为流动相,梯度洗脱,检测波长为270nm,以大黄酸为参照峰.结果共有18个共有峰.此法为有效地控制唐古特大黄乙醇提取物的质量提供了依据.

捕食风险对高原鼠兔行为的影响

我们在野外条件下利用赤狐的粪尿增加高原鼠兔的捕食风险，采用目标动物抽样法对高原鼠兔的5种行为进行观察，分析天敌动物气味增加与天敌动物数量增加对高原鼠兔行为影响的差异，探讨高原鼠兔对捕食风险的权衡能力及面对不同风险的行为决策。2001年，在捕食风险处理样方中观察雄性成体18只，雌性成体25只，雄性幼体35只和雌性幼体42只，在对照样方中观察雄性成体14只，雌性成体15只，雄性幼体22只和雌性幼体11只；2002年，在捕食风险处理样方中观察雄性成体7只，雌性成体12只，在对照样方中观察雄性成体8只，雌性成体15只。研究结果表明：增加赤狐的气味后，高原鼠兔通过改变行为策略以适应捕食风险的增加。当气味源刚放入后，与对照样方比较，高原鼠兔明显增加了观察和呜叫的频次，相应减少了取食的频次，且随着时间的推移，高原鼠兔并未对气味产生适应性。当天敌动物的数量增加后，赤狐气味的增加对高原鼠兔行为的影响较小，在捕食风险超出高原鼠兔的耐受范围时，高原鼠兔扩散。同时，高原鼠兔的行为在雌雄之间、成体与幼体之间没有明显的不同，雌雄个体、成幼体均采用相同的行为策略减小捕食风险。以上结果表明：捕食风险明显影响高原鼠兔的行为，高原鼠兔能够权衡捕食风险的大小，并依据风险水平的高低采用相应的行为策略，其行为调节符合捕食风险时间分配的假说。

Effect of Tannic Acid on the Growth and Survival of Root Vles (Micortus oeconomus)

The objective of this study was to investigate the effects of tannic acid on the gworth and survival of small mammalian berbirvores. Measurements were conducted with weaned root voles fed with 3% or 6% tannic acid and 10% or 20% protein in their diets. The results indicated that the effect of tannic acid on growth rate of weaned root voles was greater when given a lower protein diet than a higher protein diet. After 20 d, with 10% protein diets, mean growth rates of the weaned voles fed with 3% or 6% tannic acid were -0.135 g/d and -0.25 g/d, respectively. When given 20% protein diet, mean growth rates of weaned root voles fed with 3% and 6% tannic acid for 20 d were 0.134 g/d and -0.116 g/d, respectively. Food utilization efficiencies of the voles fed with 3% and 6% tannic acid diets were significantly lower than that of the control diet at the level of 10% protein. When given the 20% protein diet, food utilization efficiencies of weaned voles fed with 6% tannic acid were significantly lower than that of the voles fed with 3% tannic acid diet or the control diet with the 10% protein diets, the average survival days of the weaned voles fed with 3% and 6% tannic acid diets decreased 26.23% and 49.36% compared to controls at the end of trial period, respectively. With 20% protein diets, the average survival of weaned voles given 6% tannic acid diet decreased 39.41% compared to controls at the end of trial period, although weaned voles given 3% tannic acid had a slight decrease of average survival days. The results of study suggested that tannins could substanitially affect the individual performance of weaned root voles.

Diurnal, seasonal and annual variation in net ecosystem CO2 exchange of an alpine shrubland on Qinghai-Tibetan plateau

Thus far, grassland ecosystem research has mainly been focused on low-lying grassland areas, whereas research on high-altitude grassland areas, especially on the carbon budget of remote areas like the Qinghai-Tibetan plateau is insufficient. To address this issue, flux of CO2 were measured over an alpine shrubland ecosystem (37 degrees 36'N, 101 degrees 18'E; 325 above sea level [a. s. l.]) on the Qinghai-Tibetan Plateau, China, for 2 years (2003 and 2004) with the eddy covariance method. The vegetation is dominated by formation Potentilla fruticosa L. The soil is Mol-Cryic Cambisols. To interpret the biotic and abiotic factors that modulate CO2 flux over the course of a year we decomposed net ecosystem CO2 exchange (NEE) into its constituent components, and ecosystem respiration (R-eco). Results showed that seasonal trends of annual total biomass and NEE followed closely the change in leaf area index. Integrated NEE were -58.5 and -75.5 g C m(-2), respectively, for the 2003 and 2004 years. Carbon uptake was mainly attributed from June, July, August, and September of the growing season. In July, NEE reached seasonal peaks of similar magnitude (4-5 g C m(-2) day(-1)) each of the 2 years. Also, the integrated night-time NEE reached comparable peak values (1.5-2 g C m(-2) day(-1)) in the 2 years of study. Despite the large difference in time between carbon uptake and release (carbon uptake time < release time), the alpine shrubland was carbon sink. This is probably because the ecosystem respiration at our site was confined significantly by low temperature and small biomass and large day/night temperature difference and usually soil moisture was not limiting factor for carbon uptake. In general, R-eco was an exponential function of soil temperature, but with season-dependent values of Q(10). The temperature-dependent respiration model failed immediately after rain events, when large pulses of R-eco were observed. Thus, for this alpine shrubland in Qinghai-Tibetan plateau, the timing of rain events had more impact than the total amount of precipitation on ecosystem R-eco and NEE.

Molecular phylogeny and biogeography of the Qinghai-Tibet Plateau endemic Nannoglottis (Asteraceae)

All taxa endemic to the Qinghai-Tibet Plateau are hypothesized to have originated in situ or from immediately adjacent areas because of the relatively recent formation of the plateau since the Pliocene, followed by the large-scaled biota extinction and recession caused by the Quaternary ice sheet. However, identification of specific progenitors remains difficult for some endemics, especially some endemic genera. Nannoglottis, with about eight species endemic to this region, is one such genus. Past taxonomic treatments have suggested its relationships with four different tribes of Asteraceae. We intend to identify the closest relatives of Nannoglottis by evaluating the level of monophyly, tribal delimitation, and systematic position of the genus by using molecular data from ndhF gene, trnL-F, and ITS region sequences. We find that all sampled species of Nannoglottis are a well-defined monophyly. This supports all recent taxonomic treatments of Nannoglottis, in which all sampled species were placed in one broadly re-circumscribed genus. Nannoglottis is most closely related to the Astereae, but stands as an isolated genus as the first diverging lineage of the tribe, without close relatives. A tentative relationship was suggested for Nannoglottis and the next lineage of the tribe was based on the ITS topology, the "basal group," which consists of seven genera from the Southern Hemisphere. Such a relationship is supported by some commonly shared plesiomorphic morphological characters. Despite the very early divergence of Nannoglottis in the Astereae, the tribe must be regarded to have its origin in Southern Hemisphere rather than in Asia, because based on all morphological, molecular, biogeographical, and fossil data, the Asteraceae and its major lineages (tribes) are supposed to have originated in the former area. Long-distance dispersal using Southeast Asia as a steppingstone from Southern Hemisphere to the Qinghai-Tibet Plateau is the most likely explanation for this unusual biogeographic link of Nannoglottis. The 23-32-million-year divergence time between Nannoglottis and the other Astereae estimated by DNA sequences predated the formation of the plateau. This estimation is further favored by the fossil record of the Asteraceae and the possible time of origin of the Astereae. Nannoglottis seems to have reached the Qinghai-Tibet area in the Oligocene-Eocene and then re-diversified with the uplift of the plateau. The molecular infragenetic phylogeny of the genus identifies two distinct clades, which reject the earlier infrageneric classification based on the arrangement of the involucral bracts and the length of the ligules, but agree well with the habits and ecological preferences of its current species. The "alpine shrub" vs. "coniferous forest" divergence within Nannoglottis was estimated at about 3.4 million years ago when the plateau began its first large-scale uplifting and the coniferous vegetation began to appear. Most of the current species at the "coniferous forest" clade of the genus are estimated to have originated from 1.02 to 1.94 million years ago, when the second and third uprisings of the plateau occurred, the climate oscillated and the habitats were strongly changed. The assumed evolution, speciation diversity, and radiation of Nannoglottis based on molecular phylogeny and divergence times agree well with the known geological and paleobotanical histories of the Qinghai-Tibet Plateau. (C) 2002 Elsevier Science (USA). All rights reserved.

贵州区域农业生态环境综合评价

科学地评价贵州的农业生态环境, 可以为西部大开发中的区域发展战略提供理论依据。本文应用模糊综合评价方法, 通过对贵州各个区域的自然、社会、经济环境的系统研究, 对贵州各区域农业生态环境进行了客观评价, 从定量角度对各区农业生态环境加以探讨; 并对西部大开发中贵州农业生态环境保护提出了合理建议。

贵州赫章土法炼锌导致的重金属积累

贵州省赫章县的土法炼锌不仅导致植被的破坏，而且使附近土壤和溪流沉积物中重金属有不同程度的积累，土壤中w(Pb)达到37．24×lO^-6～30100×lO^-6，w(Zn)为162．23×lO^-6～31625×lO^6。，w(Cd)为O．50×lO^-6～113×lO^-6，大大超过了当地的土壤背景值；沉积物中w(Pb)达到325．00×lO^-6～21850×lO^-6，w(Zn)为1250．00×10^-6～30425×10^-6，w(Cd)为25×10^-6～97×10^-6。土壤和沉积物中Pb、Zn含量与Al2O3有极显著的正相关性；土壤中重金属Pb、压含量与A12O3有极显著的正相关性，而沉积物中Pb、压含量与Al2O3则没有相关性。土壤和沉积物中铁矿物(铁氧化物和氢氧化物)对重金属的强烈固定作用。连续提取法对化学形态研究表明，Pb、办在土壤中主要表现为铁锰氧化物结合态与残渣态，而在沉积物中则主要为碳酸盐结合态、残渣态和铁锰氧化物结合态。土壤中可交换态Pb、压所占的比例很小，但其绝对含量变化较大，w(Pb)从最低2．75×lO^-6到最高310．4l×l0^-6，w(Zn)4．94×lO^-6～321．10×lO^-6。沉积物中w(Pb)7．42×lO^-6～98．9l×lO^-6;w(zn))9．97×lO^-6～72．67×lO^-6。土壤中重金属Pb、压的有效性程度明显高于溪流沉积物，对生态环境的潜在危害更大.

离子色谱-六极碰撞等离子质谱法同时测定水样的砷形态

经阴离子色谱柱分离,3 mmol/ L KH2PO42K2HPO4 (含3 %CH3OH改进剂) 的淋洗液等梯度淋洗,用六极碰撞等离子体质谱仪在线测定了三种砷形态。检出限分别为:As( Ⅴ) 0. 49μg/ L ,As ( Ⅲ) 0. 39μg/ L ,DMA 0. 16μg/L。重复性优于6. 0 % ,三日复现性优于6. 1 %。为了检验该方法的实际应用性,测定了贵阳市饮用水源阿哈湖的湖水及入湖河水中的砷形态,结果比较理想。

《陕西铜厂矿田构造成矿动力学》书评

该书以陕西勉(县)-略(阳)-阳(平关)地区铜厂铜金多金属矿田为例，在总结构造成矿动力学的理论和方法基础上，从成矿地质背景、矿床地球化学、矿田地质力学、矿田构造地球化学及矿田构造应力场等方面对研究区进行了系统地构造成矿动力学研究，根据所获研究成果对该区进行了隐伏矿定位预测。全书约35万字，共分7章，其中图¨6幅、表53个、照片62张。陈庆宣院士为该书作了序。

铜在水蒸气相中溶解的初步实验

近年来地质证据和少量的实验研究证实,相当量的铜可以在气相中迁移,人们认识到铜在气相中迁移是一种重要的地球化学过程,但目前关于铜在气相中溶解反应机理的研究还相当缺乏.本文通过溶解度法,在310～350℃,压力为4.2～10 MPa的条件范围内,实验研究了铜在不饱和水蒸气相中的溶解度.结果表明：水蒸气的存在大大增强了铜在气相中的溶解度;恒定温度下,铜在气相中的溶解度随着水蒸气压的增加而增大;气相中铜可能以水合物的形式存在,铜在气相中的溶解可由以下反应表述：CuClm^solid ＋nH2O^gas=CuClm·（H2O）n^gas（m=1,2）,其中水合数随着温度升高而下降,温度为310℃水合数n为～6,330℃为～5,350℃为～4.研究结果明确显示,气体溶剂H2O与铜之间的反应可大大增强铜在气相中的溶解和迁移能力。

渔塘坝硒矿床富硒硅质岩的成因

下二叠统茅口灰岩顶部含碳硅质岩段(P13m )是渔塘坝硒矿床的主要富Se层位, 具有水平层理和纹层理构造, 硅质岩平均含Se 1646 μg·g-1, 富含有机碳、Al2O3和SiO2, 而S含量较低, 除主要富集Se元素外, 其他如Mo, Cd, V, Co等也有较高富集. 稀土总量低, 轻稀土略显富集. 样品富集较重的Si同位素, δ 30Si值变化不大, 范围在1.1‰~1.2‰之间. 通过常量元素、微量元素、稀土元素以及Si同位素组成特征可以判断渔塘坝富硒硅质岩形成于浅海-半深海缺氧环境, 并主要受生物化学作用控制.

地史早期岩石中的铅锌演化--狼山-渣尔泰山中元古代铅锌成矿的物质基础

以中国内蒙古狼山一渣尔泰山中元古代SEDEX型铅．锌成矿带为例，研究了该区从太古代到中元古代地壳岩石的铅锌含量和变化关系以及与成矿的关系。研究发现，从早到晚，岩石SiO2和K2O含量升高，铅含量也与二者同步增加；FeO、MgO、CaO及Na20含量呈下降趋势，锌含量也同步降低。在太古代时，岩石的Zn／Pb比值一般〉8，中元古代时这一比值降低为2～4。矿石的Zn／Pb比值与基底岩石Zn／Pb比值具有很好的一致性。铅锌这种随时间的变化与中元古代铅的暴发性成矿及大规模铅锌共生矿床的形成是同步的，说明基底岩石中的铅和锌是该成矿带SEDEX矿床成矿的物质基础.

湘南瑶岗仙钨矿床成矿流体地球化学

瑶岗仙钨矿床位于湘东南后加里东隆起和湘、桂、粤北海西—印支坳陷带的交接部位，是南岭地区最典型的石英脉型钨矿床之一。为了深入研究瑶岗仙钨矿的成矿机制，本文在野外地质工作基础上，选取有代表性的样品，进行了氦、氩同位素以及碳、氧、硫稳定同位素研究，探讨了矿床成矿流体的来源，成岩成矿的关系，并初步讨论了矿床的成因模式。论文主要获得以下认识： （1）对瑶岗仙矿区不同硫化物中流体包裹体的氦、氩同位素系统测定表明，该矿床毒砂流体包裹体中3He/4He比值为0.58~2.60 Ra；黄铁矿和黄铜矿流体包裹体中3He/4He比值分别为0.41~1.26 Ra 和0.37~0.43 Ra，黑钨矿流体包裹体中氦同位素组成相对变化较大，其3He/4He比值为0.05~0.49 Ra，这些He同位素组成均明显高于地壳相应值；毒砂流体包裹体中的40Ar/36Ar变化范围在309.94~454.39；黄铁矿流体包裹体中的40Ar/36Ar变化范围在409.12~1822.31；黄铜矿和黑钨矿流体包裹体中的40Ar/36Ar变化范围分别为673~886和325~903，明显高于饱和大气雨水的40Ar/36Ar值。上述氦、氩同位素组成揭示瑶岗仙钨矿床中的成矿流体具有壳、幔两端元混合的特点。结合区域地质构造演化和成矿年代学的研究成果，本文认为瑶岗仙钨矿床的成矿流体是瑶岗仙花岗岩浆分异出的含有地幔He的岩浆流体与大气成因地下水二端元混合的产物。 （2）层解石和方解石的C、O同位素显示，该矿方解石的13CPDB和18OSMOW的变化范围为-2.2‰~ -7.0‰（均值为-4.8‰）和5.6‰~14.4‰（均值为11.3‰）；层解石的13CPDB和18OSMOW的变化范围为-5.5‰~ -6.3‰（均值为-5.8‰）和12.7‰~14.3‰（均值为13.8‰）；该矿方解石、层解石的C、O同位素组成与赣南西华山钨矿床非常类似。这些C、O同位素指示，该矿的成矿流体主要来自岩浆水，后期有少量大气降水的参与。 （3）对瑶岗仙矿区不同硫化物的硫同位素研究表明，该矿硫化物δ34S值的变化范围很窄，为-2.0‰~1.5‰之间，且具有明显的塔式分布。这些特征暗示，该矿的硫来源单一，主要来自岩浆。 （4）瑶岗仙花岗岩过去被视为典型的S型花岗岩，但本文研究发现该花岗岩普遍含有地幔He。结合区域构造背景的最新研究成果，本文认为，原来被认为“由地壳物质重熔形成的”瑶岗仙S型花岗岩体，实际上也是一种岩石圈伸展背景条件下壳幔相互作用的产物，地幔物质和能量的参与在该花岗岩的形成过程中发挥了重要作用。 （5）瑶岗仙钨矿床与矿区复式花岗岩体具有密切时空关系，而且该矿的主要成矿流体和成矿物质均来自矿区花岗岩，故两者亦应具成因联系。