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排序方式: 共有38条查询结果,搜索用时 15 毫秒
1.
云南高黎贡山荨麻科楼梯草属六新种   总被引:1,自引:0,他引:1  
描述了云南高黎贡山荨麻科楼梯草属6新种:三茎楼梯草、少叶楼梯草、指序楼梯草、片马楼梯草、茨开楼梯草和拟宽叶楼梯草。  相似文献   
2.
Halophilic archaeon A J6 was isolated and purified from the Altun Mountain National Nature Reserve of the Xinjiang Uygur Autonomous Region.Strain AJ6 is a Gram-negative rod whose size is 0.2-0.6 by 1.6-4.2 μm,wherein a few cells are globular.The optimum salt concentration for its growth is 20% NaC1 and 0.6% Mg2+,and the optimum pH is 6.0-7.0.Morphological,physiological,and biochemical characteristics of strain AJ6 were observed.The 16S rRNA encoding gene (16S rDNA)sequence of strain A J6 was amplified by PCR,and its nucteotide sequence was determined subsequently."Clustalw"and"PHYLIP"software bags were used to analyze the 16S rDNA sequence;the homology was compared,and then the phylogenetic tree was established.The results indicate that strain AJ6 is a novel species of the genus Natrinema.The GenBank accession number of the 16S rDNA sequences of strain AJ6 is AY277584.  相似文献   
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A ten-year multidisciplinary, multi-national and multi-institutional biodiversity inventory project in the Gaoligong Shan region of western Yunnan Province, China generated more than 35,000 specimens of the beetle (Coleoptera) family Carabidae. In this report, first of a planned series, we focus on diversity in tribe Zabrini. Our study of just over 1300 specimens of zabrine carabids from the project, all in genus Amara Bonelli, found a total of 13 species, all previously described, to occur in the study area, with none of them strictly endemic. We present a key for identification of adults of these species, as well as nomenclatural data, diagnoses, illustrations of dorsal habitus and male genitalia, and information about geographical, altitudinal and habitat distributions within the study area and overall geographical distribution for each species. Distributions of the species within the study area are compared, and broader geographical range patterns are characterized. We also discuss a possible role of the Gaoligong Shan region as one source area for the present-day fauna of the Himalaya and southern edge of the Qinghai-Xizang (Tibetan) Plateau.  相似文献   
5.
骨缘当归的化学成分   总被引:2,自引:0,他引:2  
骨缘当归Angellica cartilaginomarginata var.foliata Yuan et Shen,别名:山藁本、野芹菜(江苏),仅分布于江苏和浙江。在江苏镇江等地用干燥全草作山藁本入药,其化学成分未见报道。 样品采自江苏省句容县。将干根磨粉,提取物经中性氧化铝层析,根据色谱及光谱鉴定为两种脂肪酸、四种已知香豆素和一种植物甾醇即:正葵酸(n-capric acid)、月桂酸(lauric acid)、骨缘当归素(cartilaginomarginadin)、蝉翼素(pteryxin)、白花前胡素F(praeruptorin F)、佛手柑内酯(bergapten)及β-谷甾醇(β-sitosterol)。  相似文献   
6.
酸性矿山废水污染的水稻田土壤中重金属的微生物学效应   总被引:21,自引:1,他引:20  
采样调查了广东大宝山地区受酸性采矿废水长期污染的亚热带水稻田的土壤理化性质 ,重金属 Cu、Pb、Zn、Cd的全量及其 DTPA浸提量 ,以及微生物生物量及其呼吸活性等指标。利用主成分和逐步回归分析了影响土壤重金属的有效性及其微生物学效应的因素。结果表明 :土壤高含硫 ,强酸性 ,有机碳、全氮较低 ,4种金属的全量普遍超标。DTPA可提取态金属含量较高 ,不仅与其全量呈显著正相关 ,而且与土壤酸度和粘粒含量正相关 ,和 Mn含量负相关。过量的金属显著降低了土壤微生物生物量 C、N、微生物商、生物量 N/全 N比 ,并抑制了微生物呼吸强度和对有机碳的矿化率 ,导致了土壤 C/N比的升高。同时 ,金属对微生物群落及生理代谢指标 ,如微生物生物量 C/N比和代谢商的影响不显著。 DTPA可提取态金属 ,特别是 DTPA- Cu是导致微生物生物量和活性指标变化的主要因素。以有机碳 (或全氮 )为基数的复合微生物指标降低了土壤性质差异造成的干扰 ,较单一指标更能准确指示微生物对金属胁迫的反应。土壤硫没有对金属有效性和微生物指标产生明显影响 ,但其氧化过程可能引起酸化和金属离子的释放  相似文献   
7.
Two new species,Meconopsis muscicola and M.yaoshanensis(Papaveraceae),are described and characterized.Differences separating them from similar species are discussed and photos showing their diagnostic features are provided.  相似文献   
8.
Abstract: The secretive nature of snow leopards (Uncia uncia) makes them difficult to monitor, yet conservation efforts require accurate and precise methods to estimate abundance. We assessed accuracy of Snow Leopard Information Management System (SLIMS) sign surveys by comparing them with 4 methods for estimating snow leopard abundance: predator:prey biomass ratios, capture-recapture density estimation, photo-capture rate, and individual identification through genetic analysis. We recorded snow leopard sign during standardized surveys in the SaryChat Zapovednik, the Jangart hunting reserve, and the Tomur Strictly Protected Area, in the Tien Shan Mountains of Kyrgyzstan and China. During June-December 2005, adjusted sign averaged 46.3 (SaryChat), 94.6 (Jangart), and 150.8 (Tomur) occurrences/km. We used counts of ibex (Capra ibex) and argali (Ovis ammon) to estimate available prey biomass and subsequent potential snow leopard densities of 8.7 (SaryChat), 1.0 (Jangart), and 1.1 (Tomur) snow leopards/100 km2. Photo capture-recapture density estimates were 0.15 (n = 1 identified individual/1 photo), 0.87 (n = 4/13), and 0.74 (n = 5/6) individuals/100 km2 in SaryChat, Jangart, and Tomur, respectively. Photo-capture rates (photos/100 trap-nights) were 0.09 (SaryChat), 0.93 (Jangart), and 2.37 (Tomur). Genetic analysis of snow leopard fecal samples provided minimum population sizes of 3 (SaryChat), 5 (Jangart), and 9 (Tomur) snow leopards. These results suggest SLIMS sign surveys may be affected by observer bias and environmental variance. However, when such bias and variation are accounted for, sign surveys indicate relative abundances similar to photo rates and genetic individual identification results. Density or abundance estimates based on capture-recapture or ungulate biomass did not agree with other indices of abundance. Confidence in estimated densities, or even detection of significant changes in abundance of snow leopard, will require more effort and better documentation.  相似文献   
9.
湖南张家界天门山种子植物区系新资料   总被引:6,自引:0,他引:6  
基于对湖南省张家界市天门山国家森林公园种子植物标本的采集鉴定,报道了湖南省新记录13种2变种,隶属于11科15属。即小山飘风Sedum filipes Hemsl.、绿花石莲Sinocrassula indica(Decne.)Berger var.viridiflora K.T.Fu、扇叶虎耳草Scocifraga rufescens Balf.var.flabellifolia C.Y.Wu et J.T.Pan、滇池海棠Malus yunnanensis(Franch.)Schneid.、北枳棋Hovenia dulcis Thtmb.、橄榄槭Acer olivaceum W.P.Fang et P.L.Chiu、大叶柴胡Bupleurum longiradiaum Turcz.、重齿当归Angelica biserrata(R.H.Shan et C.Q.Yuan)C.Q.Yuan et R.H.Shan、羌活Notopterygium incisum T.T.Ting ex H.T.Chang、直瓣苣苔Ancylostemon sarasilia(Hemsl.)Craib、野丁香Leptodermis potanini Batalin、毛华菊Dendranthema vestitum(Hemsl.)Ling、长冠鼠尾草Salvia pleetranthoides Griff.、茖葱Allium victorialis Linn.、节根黄精Polygonatum nodosum Hua。其中羌活属和野丁香属为湖南分布新记录属。凭证标本均存放在中南林业科技大学树木标本室(CSFI)。  相似文献   
10.
Halophilic archaeon AJ6 was isolated and purified from the Altun Mountain National Nature Reserve of the Xinjiang Uygur Autonomous Region. Strain AJ6 is a Gram-negative rod whose size is 0.2–0.6 by 1.6–4.2 μm, wherein a few cells are globular. The optimum salt concentration for its growth is 20% NaCl and 0.6% Mg2+, and the optimum pH is 6.0–7.0. Morphological, physiological, and biochemical characteristics of strain AJ6 were observed. The 16S rRNA encoding gene (16S rDNA) sequence of strain AJ6 was amplified by PCR, and its nucleotide sequence was determined subsequently. “Clustalw” and “PHYLIP” software bags were used to analyze the 16S rDNA sequence; the homology was compared, and then the phylogenetic tree was established. The results indicate that strain AJ6 is a novel species of the genus Natrinema. The GenBank accession number of the 16S rDNA sequences of strain AJ6 is AY277584. Translated from Journal of Zhejiang University (Science Edition), 2005, 32(1) (in Chinese)  相似文献   
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