233 resultados para northwestern Sichuan Province

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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Triplophysa lixianensis, a new nemacheiline loach species, is described from the Min Jiang of the upper Yangtze River drainage in Sichuan Province, South China. It can be separated from all other species of Triplophysa by having a unique combination of the following characters: posterior chamber of gas bladder greatly reduced or absent; caudal peduncle columnar with a roughly round cross- section at its beginning; anterior edge of lower jaw completely exposed or uncovered by lower lip; intestine short, forming a zigzag loop below stomach; dorsal- fin origin closer to caudal- fin base than to snout tip; pelvic fin inserted anterior to dorsal- fin origin; snout length 50.6 - 57.5 % of head length; eye diameter 12.3 15.4 % of head length; caudal peduncle length 25.1 - 27.1 % of standard length; anal fin with five branched rays; lower lip greatly furrowed with two thick lateral lobes; and body smooth or scaleless.

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除植被冠层的光合作用之外,土壤的呼吸作用是陆地生态系统碳收支中最大的通量。土壤呼吸即使发生较小的变化也能显著地减缓或加剧大气中CO2浓度的增加,从而明显影响到全球气候变化。土壤呼吸速率变化与否以及变化的方向可以反映生态系统对环境变化的敏感程度和响应模式。尽管如此,土壤呼吸仍是一个为人们了解不多的生态系统过程。 草地生态系统是陆地生态系统的一个重要组成部分。针对草地土壤呼吸进行野外实验研究和相应方法论的探讨将对区域乃至全球碳源汇性质的准确估算具有重要的科学意义。然而,近几年来关于草地土壤呼吸的主要研究工作都集中在温带草原和部分热带草原,而针对高寒草甸生态系统土壤呼吸的研究报道还很少。 2008年4月至2009年4月期间,我分别在2008年6、8、10、12月和2009年2月和4月分6次对川西北的典型高寒草甸群落的土壤呼吸进行观测,分析了不同类型高寒草甸群落土壤呼吸的季节变化特征以及环境因子和放牧模式对其影响。主要研究结果如下: 1)该地区高寒草甸生态系统在生长季(6月~8月)土壤呼吸速率较大(6.07~9.30μmolCO2¡m-2¡s-1 ) , 在非生长季( 12 月~ 2 月) 较小( 0.16 ~0.49μmolCO2¡m-2¡s-1 ) 。土壤CO2 年累积最大释放量为3963 ~ 5730gCO2¡m-2¡yr-1,其中,生长季土壤CO2的释放量占年总释放量的85%~90%。非生长季占10%~15%。非生长季所占比例略小于冬季积雪覆盖地区的冬季土壤呼吸占年土壤呼吸量的比例(14%~30%)。温度,尤其地温,是影响该地区高寒草甸生态系统土壤呼吸速率的最主要环境因子。土壤呼吸速率与地上生物量和土壤水分之间没有显著相关性,但是土壤含水量过大会导致土壤呼吸速率下降。 2)在观测期内,草丘区的土壤呼吸显著高于对照区的土壤呼吸,其最大土壤呼吸速率为16.77μmolCO2¡m-2¡s-1,土壤CO2 年累积最大释放量为8145gCO2¡m-2¡yr-1,是对照区的近2 倍。由于草丘在高寒草甸中占有较大的面积比例(近30%),因此,它将对高寒草甸生态系统的碳循环起着重要的作用。 3)放牧模式不仅可以影响高寒草甸群落的土壤CO2 排放,而且还可以改变土壤呼吸的温度敏感性(Q10)。本研究表明,在生长季有长期放牧活动干扰时将会增加土壤向大气中释放二氧化碳的速度,促使土壤碳库中碳的流失。禁牧样地的土壤呼吸速率在刚禁牧时先迅速增大,随着禁牧时间的延长土壤呼吸速率将会下降。此外,与其它放牧模式相比,冬季放牧将高寒草甸群落土壤呼吸速率在生长季达到最大值的时间明显向后推迟。不同放牧模式下高寒草甸群落土壤呼吸的Q10 值大小顺序为:禁牧一年群落>冬季放牧群落>禁牧三年群落>夏季放牧群落>自由放牧群落。 4)基于呼吸室技术的观测方法中,测量前的剪草处理可以明显改变该地区高寒草甸群落的土壤温度和土壤呼吸速率。在生长季,剪草处理将使土壤呼吸速率的瞬时响应增加90%左右。由于剪草处理明显增加了剪草样方白天的土壤温度,而土壤温度与土壤呼吸之间存在着极显著的指数相关关系,因而剪草处理导致土壤呼吸速率迅速增加。因此,在高寒地区基于呼吸室技术观测的土壤呼吸应当进行校正。 综上所述,川西北高寒草甸生态系统土壤呼吸速率在生长季较高,而在非生长季较低。土壤温度是影响该地区土壤呼吸的最主要环境因子。在实验观测期,草丘区土壤呼吸速率显著高于对照区的,是对照区土壤呼吸速率的近2倍。由于测量前的剪草处理可以明显改变待测点的土壤呼吸速率,因此,应对在高寒地区基于呼吸室技术观测的土壤呼吸进行校正。 Soil respiration is the second largest component (less than plant phtotosynthesis) of carbon dioxide flux between terrestrial ecosystems and the atmosphere. A minor change in soil respiration rate can significantly slow down or accelerate the increase of atmospheric CO2 concentration that is closely related to global climatic change. In turn, the change in the flux direction and rate of soil respiration may indicate the elasticity and stability of ecosystems to global changes and human disturbance. However, soil respiration is still an ecosystem process that has been poorly understood. Grassland ecosystem is an important component of the terrestrial ecosystem. Accurately estimating the CO2 flux from soil to atmosphere in situ is the key to evaluating the carbon resource and sink regionally or globally. Despite of extensive studies on the temperate and tropic grasslands, the soil respiration of alpine meadows has not substantially been measured. In the current study, soil respiration was measured for an annual cycle from April, 2008 to April, 2009 for the alpine meadow in northwestern Sichuan Province of China to determine the seasonal variation of soil respiration for the typical plant communities. The results are shown as follows: 1) Large seasonal variation of soil respiration was observed in the alpine meadow. The rate of soil respiration was the greatest (6.07~9.30μmolCO2¡m-2¡s-1) in June and the smallest (0.16 ~ 0.49μmolCO2¡m-2¡s-1) occurred from December to February in the non-growing season. The total emission of soil CO2 was estimated as 3963~5730 gCO2¡m-2¡yr-1, 85%~90% of which was released during the growing season, and 10%~15% during the non-growing season which was slightly less than the ratio of winter and annual CO2 flux from soil. Temperature, particularly the soil temperature, was the major environmental factor regulating the soil respiration. Significant and positive relationships were not found between soil respiration and soil moisture and between soil respiration and plant above-ground biomass, but excessive soil water content would decrease in the rate of soil respiration. 2) The rate of soil respiration in grass hummock communities was up to 16.77μmolCO2¡m-2¡s-1, which was about twice as great as in the controls (communities located in low and even sites). Considering the large proportion (about 30% on average) of hummock area in the meadow, it can be concluded that the hummocks played an important role in the carbon cycling of the study ecosystem. 3) Grazing patterns affected the flux of CO2 emission and the temperature sensitivity of soil respiration (Q10) in the alpine meadow. Grazing during growing season increased the rate of soil respiration. The rate of soil respiration increased significantly immediately after the alpine meadow being fenced, but thereafter decreased. In addition, grazing in winter delayed the peak respiration rate relative to the non-grazing mode. The Q10 value was the largest in the non-grazed area for one year, and next came the area with grazing in winter, followed by the non-grazed area for three years, the area with grazing in summer, and the non-limited grazed area. 4) In the chamber-based techniques, clipping manipulation before each measurement increased the transient rate of soil respiration by about 90% in the summer of the alpine meadow. As increase in soil temperature at daytime in the clipped plots by clipping and the exponential relationship between soil respiration and temperature, clipping manipulation led to increase in the rate of soil respiration. This suggested that a correction should be done for the techniques if employed in alpine and cold regions. In summary, the rate of soil respiration in the alpine meadow was the greatest in June and the smallest occurred from ecember to February in the non-growing season. Soil temperature was the major environmental factor regulating the soil respiration. The rate of soil respiration in grass hummock communities was up to 16.77μmolCO2¡m-2¡s-1, which was about twice as great as in the controls. A correction should be done for the techniques if employed in alpine and cold regions, because of the effect of clipping manipulation on soil temperature and respiration.

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Geographic variation of Chevrier's field mouse (Apodemus chevrieri) (Milne-Edwards, 1868) (Muridae: Murinae) from southwestern China based on cranial morphometric variables. Zoological Studies 47(4): 393-401. A sample of 134 specimens of Apodemus chevrieri was investigated in the present study. Individuals were divided into male and female groups, and these were respectively subjected to multivariate analysis. Results indicated that 3 geographic populations of A. chevrieri inhabit southwestern China: a Sichuan population in western Sichuan Province; a northwestern Yunnan population ranging from northwestern Yunnan Province eastward to southern Sichuan Province; and a central Yunnan population in central Yunnan Province. In addition, a coefficient of difference analysis was performed among these 3 geographic populations. The results suggested that these 3 geographical populations of A. chevrieri belonged to 2 subspecies. Furthermore, we discuss the relationships of the subspecific differentiation of A. chevneri with changes in latitude in southwestern China.

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在千焦拍瓦高功率啁啾脉冲放大系统设计中,为了尽量消除增益窄化和增益饱和效应的影响,同时尽可能提高高功率激光输出脉冲信噪比参数,激光脉冲时空和光谱的整形问题备受关注.提出一种光谱整形新方法,利用特定结构的多层介质膜反射镜,可实现对大能量高功率啁啾脉冲钕玻璃放大系统中啁啾脉冲的光谱整形.研究结果表明,只要合理选择多层介质膜系的结构参数,可有效地控制其反射率分布,且在保证反射相位基本不变的条件下其调制度可超过60%.针对钕玻璃1053nm波长设计而成的光谱整形反射镜,反射带宽可达到196nm,色分辨率约为0.1nm,在几十纳米波长范围所对应的相位偏差小于12mrad,相当于λ/524,能够满足"神光Ⅱ"千焦拍瓦改造的技术指标要求.

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Tongjiang cattle are a local cattle population of Sichuan Province, China, numbering approximately half a million in 2005. They have long been grouped into the Bashan breed, although they have a unique breeding history and phenotypic characteristics, as w

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The authors thank the anonymous reviewer for helpful comments on the early version of the manuscript. This work was financially supported by the earmarked fund for Modern Agro-industry Technology Research System, the Science Fund for Young Scholars in Sichuan Province (Grant No: ZQ 026-017), and the National 863 Project of China (No. 2008AA101001).

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From 26 March to 2 August 2003, both the time budget and the diurnal rhythm of behavior of breeding Black-necked Cranes (Grus nigricollis) were studied at Ruoergai Wetlands National Natural Reserve, Sichuan Province, China. The breeding season was divided

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Pseudobagrus fui Miao is a valid bagrid species that can be separated from all its congeners in having 27-33 anal-fin rays. Among the species of Pseudobagrus, it forms part of a group of approximately 20 species putatively characterized by having a smooth anterior margin of the pectoral-fin spine and short maxillary barbels not extending to the base of the pectoral-fin spine. Pseudobagrus fui, together with P. nitidus and P. vachelli, can be differentiated from all other fork-tailed species of this group by having no fewer than 20 branched anal-fin rays, the posterior end of the anal-fin base posterior to the vertical through the posterior end of the adipose-fin base, and anal-fin base longer than the adipose-fin base. It further differs from P. nitidus in having a gas bladder without beaded lateral and posterior margins, and from P. vachelli in having short maxillary barbels not extending to the base of the pectoral-fin spine. Pseudobagrus fui is currently known from the main stream of the upper Yangtze River and its tributaries, the Min River, Jialing River, Tuo River, Wu River and Chishui River in Sichuan Province, Guizhou Province, and the Chongqing City. The identity and nomenclature of Pseudobagrus nitidus is also discussed.

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The type species of the cyprinid genus Sinilabeo was misidentified as Varicorhinus tungting, and the species under the generic name belong to Bangana and Linichthys. In order to make Sinilabeo available, its type species is fixed under Article 70.3.2 of the 1999 edition of the International Code of Zoological Nomenclature as S. hummeli, a new species herein described from the upper Yangtze River basin in Chongqing City and Sichuan Province, South China. A re-definition is provided for Sinilabeo. It resembles Qianlabeo in having an upper lip only present in the side of the upper jaw and uncovered by the rostral fold, but missing in the median part of the upper jaw that, instead, bears a thin, flexible, and cornified sheath, covered by the rostral fold, a character that can separate both from all other existing genera of Asian labeonins. However, Sinilabeo is distinguished from Qianlabeo in the presence of a rostral fold disconnected from the lower lip; a broadly interrupted postlabial groove only restricted to the side of the lower jaw; an upper lip, which is only present in the side of the upper separated from it by a groove; 9-10 branched dorsal-fin rays; two pairs of tiny maxillary barbels.

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景观边界是特定时空尺度下相对均质的景观之间所存在的异质性过渡带,作为景观的一个四维组分,边界动态直接反映景观变化,与基于斑块的研究相比,明确景观边界的生态意义是理解景观过程的一个新的切入点。边界效应是景观边界最显著特征之一,也是当前生态学领域的研究热点,但大部分研究集中在生态系统及其以下尺度,对大尺度上的研究涉及内容尚少。 本文以岷江上游地区为例,利用TM影像数据、林相图、土地利用图和野外实测数据,应用RS、GIS、SPSS、Fragstats等软件的数据处理、分析、运算功能,研究了景观边界网络格局的变化,并分析了与之相关的生态过程;研究了类型水平上森林景观的边界效应以及景观尺度上林农复合景观的边界网络效应。旨在揭示岷江上游景观格局的变化趋势及其驱动因子,以及林农复合景观格局的生态效应,从而为研究区土地利用提供科学参考。研究结果如下: (一)在岷江上游地区的13种景观边界类型中,建筑用地边界和农田边界是人工边界,同时也都是清晰边界;但林地、灌木林地、草地等自然景观之间的边界并不都是模糊边界。冰雪边界是典型的随季节变化的变动型边界,其它边界在年内的变化则相对稳定。 (二)在1974-2000年期间,由于人为干扰强度的加剧,岷江上游景观边界网络结构变得更加复杂,在早期以边界长度增加为主,网络连接度变大,在后期以边界数量和结点数量增加为主,网络连接度变小;森林景观与低坡位景观类型间的边界减少,森林下线上移;农田与林地的边界在早期增加,1986年后减少,而与灌木林地的边界持续增加;基于边界特征的格局分析表明,森林景观结构变得简单化,而农田、灌木林地、草地等景观类型的结构变得更加复杂。 在景观水平上,基于边界和结点特征的格局指数与对应的基于斑块特征的格局指数具有基本一致的变化趋势,但基于边界和结点特征的指数对格局的变化更灵敏,在类型水平上,基于结点的格局指数比基于边界的格局指数具有更大的灵敏性,而且前者能够反映出后者反映不出的格局信息。 (三)研究区的农田边界共有5种类型,分别是农田与林地、灌木林地、草地、水体、建筑用地之间的边界,总长6583.4km;其中林农边界长2473.7km,占37.6%,是除灌农边界(占农田边界总长度的44.9%)之外比例最大的农田边界类型,广泛分布在岷江干流及其支流的河谷中,海拔多在1000-3500m之间。 (1)多元线性回归分析结果表明,农田生物量的边界效应深度与海拔和坡度显著相关,与其它因子相关性不大;林地生物量的边界效应深度与海拔和坡向相关性较大,与其它因子相关性不大;林农边界对农田生物量产生正面效应,对林地生物量产生负面效应,且对农田的影响面积大于对林地的影响面积;根据回归方程计算边界效应的影响面积,2000年有14532hm2林地生物量受到林农边界网络的影响,占研究区林地面积的1.2%,有16659 hm2农田生物量受到林农边界网络的影响,占研究区农田面积的22.6%,由于边界位置、长度的变化,不同年间林农边界网络的生态效应也存在差异。 除了生物量,本文还研究了林农边界网络对林地和农田土壤水分和生物多样性的影响: (2)林农边界减少林地和农田边缘的土壤水分,岷江上游有2103 hm2农田和371 hm2林地其土壤水分受到林农边界效应的影响,分别占研究区农田面积的2.3%和林地面积的0.03%。生物多样性受林农边界网络影响的农田面积为4855 hm2,占研究区农田面积的5.37%;生物多样性受林农边界网络影响的林地面积为3401 hm2,占研究区林地面积的0.29%。 上述研究从景观边界网络的角度揭示了岷江上游近三十年的景观变化特征,在印证斑块类型所反映的景观变化特征的同时,还反映出传统格局研究方法反映不出的格局信息,为景观生态学中格局与过程研究提供了新思路,也丰富了边界效应的理论和案例研究,有关结论还可为高山峡谷区土地利用格局优化和实施退耕还林还草工程提供参考依据。

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本论文由四章组成。第一、二和三章分别报道了双花千里光、川芎和宽叶羌活的化学成分研究。从三种药用植物中共分离和鉴定了40 个化学成分,其中8个为新化合物。第四章概述了藳本属植物及日本川芎的化学成分研究进展。 第一章包括三个部分。第一部分报道双花千里光(Senecio dianthus Franch.)地上部分乙醇提取物的化学成分。采用正、反相硅胶柱层析等各种分离方法,从中共分离出8 个艾里莫酚型倍半萜内酯,其中5 个是新化合物,并且有1 个为首次发现的连接了含氮原子取代基的艾里莫酚型倍半萜内酯。它们的结构经MS、IR、NMR及X-单晶衍射等解析方法确定为2b-angeloyloxy-10b-hydroxyeremophil-7(11)-en-8a,12-olide (1)、6b-angeloyloxy-10b-hydroxyeremophil-7(11)-en-8a,12-olide (2)、2b-angeloyloxy-8b,10b- dihydroxyeremophil-7(11)-en-8a,12-olide (3)、2b-angeloyloxy-8a-hydroxyeremophil-7(11),9(10)-dien-8b,12-olide (4)和8b-amino-10b- hydroxyleremophil-7(11)-en-8a,12-olide (5)。这8 个倍半萜内酯经体外生物活性测试表明均具有通过抑制巨噬细胞增殖抵制破骨细胞增生的活性。第二部分对艾里莫酚型倍半萜内酯的质谱裂解规律进行了初步探讨。第三部分报道双花千里光茎、和叶花的挥发油成分分析。采用传统水蒸气蒸馏法分别提取了双花千里光茎、叶和花的挥发油,用气相色谱-质谱联用(GC-MS)技术分别分离鉴定了其化学成分,从茎、叶和花挥发油中各分离和鉴定出70、80 和73 种化学成分,分别占挥发油总量的91.2%、85.7%及93.4%。 第二章包括两个部分。第一部分报道川芎(Ligusticum chuanxiong Hort.)根茎乙醇提取物的化学成分。通过正、反相硅胶柱层析等分离纯化和MS、NMR及X-单晶衍射等解析方法,共分离鉴定了21 个化合物,结构类型分属于苯酞、二聚苯酞、香豆素和脂肪酸类。其中2 个为结构比较新颖的二聚苯酞类化合物:chuanxiongnolide A (19)和chuanxiongnolide B (20),化合物19 的结构经X-单晶衍射得到确证。第二部分报道川芎挥发油的化学成分。采用不同的提取方法(溶剂萃取法、水蒸气蒸馏法、CO2 超临界流体萃取法)提取川芎挥发油,同时采集不同产地(四川彭县、四川郫县、云南鹤庆)及不同品质(川芎、奶芎、苓子)的川芎产品,利用GC-MS 技术分离鉴定其挥发油的化学成分,计算各成分的相对含量,并对比分析其中的异同。 第三章报道宽叶羌活(Notopterygium forbesii Boiss.)根茎化学成分的分离纯化和结构鉴定。通过正、反相硅胶柱层析等分离纯化和MS、NMR 等解析方法,共分离鉴定了13 个化合物,结构类型分属于香豆素、二氢异香豆素、甾体和羧酸类。其中1 个新二氢异香豆素类成分鉴定为6-methoxy-hydrangenol (37)。 第四章概述了藳本属植物及日本川芎化学成分的研究进展。 This dissertation consisted of four chapters. The former three chaptersrespectively elaborated the phytochemical investigation of three herbal medicines:Senecio dianthus Franch., Ligusticum chuanxiong Hort. and Notopterygium forbesiiBoiss.. Forty compounds, including eight new ones, were isolated and identified byspectral and chemical evidence. The fourth chapter elaborated the study progress ofchemical constituents of Ligusticum genus and Cnidium offcinale. The first chapter consisted of three parts. The first part is about the chemicalconstituents of ethanol extraction and essential oils from the aerial parts of S. dianthu.Eight eremophilenolides were isolated and identified. Among them, five ones are newcompounds and one of them is a novel eremophilenolide attched with an amino group.The structures of the new compounds were identified as 2b-angeloyloxy-10b-hydroxyeremophil-7(11)-en-8a,12-olide (1),6b-angeloyloxy-10b-hydroxyeremophil-7(11)-en-8a,12-olide (2),2b-angeloyloxy-8b,10b-dihydroxyeremophil-7(11)-en-8a,12-olide (3),2b-angeloyloxy-8a-hydroxyeremophil-7(11),9(10)-dien-8b,12-olide (4) and8b-amino-10b-hydroxyeremophil-7(11)-en-8a,12-olide (5) by spectral evidence andX-ray crystallography analysis. All the compounds were evaluated for theiranti-osteoclstogenesis activity using a proliferation inhibit assay with microphagecells. The second part elementarily discussed the characteristic fragmentation oferemophilenolides isolated from S. dianthus in ESI-MS.The latter part is about thechemical constituents of essential oil extracted from stems, leaves and flowers of S.dianthus with steam distillation. By the GC-MS analysis, 70, 80 and 73 compoundswere respectively isolated and identified which accounted for more than 91.2%, 85.7% and 93.4% of total essential oil. The second chapter, including two parts, is about the the chemical constituents ofethanol extraction and essential oils from rhizomes of L. chuanxion. In the first part, twenty-one compounds were isolated and iedntified. Two ones are novel dimericphthalides and the structures were suggested as chuanxiongnolide A (19) andchuanxiongnolide B (20) by spectral evidence and confirmed by X-raycrystallography analysis. In the second part, the samples were collected from differentextract techniques (solvent extraction, steam distillation and supercriticalfluid extraction), different habitats (Peng and Pi counties, Sichuan province; Heqing,Yunnan province) and different qualities (Chuanxiong, Naixiong and Lingzi). Thechemical constituents of essential oil from L. chuanxiong were analyzed by GC-MS and were compared each other. The third chapter is about the chemical constituents of rhizomas of N. forbesii,which belongs to a endemic genus of China. Thirteen compounds were isolated andidentified. One of them is a new dihydroisocoumarin and the structure was identifiedas 6-methoxy-hydrangenol (37) by spectral evidence. The fourth chapter is a review on study progress of chemical constituents ofLigusticum species and Cnidium offcinale.