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1.
梧桐科植物在中国的地理分布   总被引:3,自引:0,他引:3  
徐颂军 《广西植物》2002,22(6):494-498-498
对中国梧桐科植物的地理分布进行研究 ,指出中国梧桐科植物的分布区 ,东起台湾的北部 (1 2 2°1 0′E) ,西至西藏的墨脱 (95°3 0′E ,2 9°2 0′N) ,北起河北的东陵和小五台山 (约 40°2 0′N) ,南达西沙群岛的永兴岛(约 1 6°1 0′N)。其分布范围主要在热带、亚热带 ,只有少数种类可分布到温带。主要根据《中国种子植物属的分布区类型》的划分原则 ,把中国梧桐科植物野生各属划分为 1 0个类型。且对中国梧桐科植物一些属的分布格局进行探讨。  相似文献   

2.
山东植物区系的演变和来源   总被引:1,自引:0,他引:1  
1 现代植物区系山东省位于我国东部、黄河下游 ,北濒渤海 ,东临黄海 ,地理范围介于北纬 34°2 3′~38°2 4′,东经 1 1 4°4 8′~ 1 2 2°4 3′之间。全省总面积为 1 5.72万 km2 ,占全国总面积的 1 .6%。属暖温带季风气候 ,沿海比较湿润 ,地带性植被主要是暖温带落叶阔叶林和松、栎类针阔叶混交林。山东省在中国植物区系的分区地位隶属于泛北极植物区、中国 -日本森林植物亚区、华北植物地区 [1 ]。据最近研究统计 ,现有野生维管植物 1 47科、61 4属 ,约 1 547种 (包括变种 ,下同 )。其中蕨类植物 2 4科 39属 1 0 5种 ,裸子植物 3科 3属 …  相似文献   

3.
广东阳春鹅凰嶂自然保护区种子植物区系研究   总被引:8,自引:1,他引:7       下载免费PDF全文
鹅凰嶂自然保护区位于广东省阳春市境内 (1 1 1°2 1′2 9″~ 1 1 1°3 6′0 3″E ,2 1°5 0′3 6″~ 2 1°5 8′40″N) ,为北热带地区。计有维管植物 2 1 0科 75 4属 1 5 80种 (包括亚种与变型 ) ,其中种子植物有 1 72科 681属 1 44 8种。研究分析和讨论了本区主要植被类型、种子植物区系及珍稀濒危植物 ,其种子植物区系特征是 :种类组成比较丰富 ,地理成分复杂 ,联系广泛 ,以热带成分占绝对优势 ,是典型的热带北缘区系性质 ;植被类型以山地雨林为主 ;区系起源古老 ,原始类群丰富 ;特有性比较高 ,珍稀濒危植物明显。建议对一些濒危物种采取有效的保护措施。  相似文献   

4.
黄山栎 ( Quercus stewardii)在植物分类学上属双子叶植物纲 ,壳斗科 ,栎属 ,为华东地区特有种。黄山栎群落为落叶阔叶林 ,分布海拔较高 ,是较典型的山地矮林 ,分布于浙江、福建、江西和安徽等省。有关黄山栎群落的研究不多 ,为了探讨该群落的特征和性质 ,以及群落的发育 ,我们对大别山天堂寨黄山栎群落进行初步调查 ,现将结果报道如下。1 自然概况金寨县的天堂寨为大别山第二主峰 ,位于皖鄂两省交界 ,约当北纬 31°1 0′~ 31°1 5′,东经 1 1 9°~1 2 0°,最高峰海拔 1 72 9m。该区地处华东亚热带气候区 ,年平均气温 1 2 .3°C。该区黄…  相似文献   

5.
江西井冈山蕨类植物研究   总被引:10,自引:0,他引:10  
井冈山地处中国南岭山地湘赣边境的罗霄山脉中段 ,北纬 2 6°2 2′~ 2 6°48′,东经 1 1 4°0 5′~ 1 1 4°2 3′。在植被分区上被认为是“中国亚热带常绿阔叶林区 ,东部 (湿润 )常绿阔叶亚地域的中亚热带南部亚地带”。该地植物种类繁多 ,区系成分复杂 ,保存着比较完整而古老的第三纪型的植物和森林生态系统 ,是许多古老植物种属的著名“避难所”〔1〕。笔者在多年野外调查和查阅标本及资料的基础上 ,系统分析了井冈山蕨类植物区系和生态分布特征。旨在为蕨类植物的研究、保护和开发利用提供理论依据。1  井冈山的蕨类植物区系地理成分…  相似文献   

6.
安徽枞阳湿地植被及植物资源的研究   总被引:9,自引:0,他引:9  
枞阳湿地地处安徽省长江干流中段北岸 ,大约北纬 30°39′~ 31°0 5′,东经 1 1 7°0 4′~1 1 7°44′。该区有 4种湿地类型 ,即湖泊湿地、长江二级河流湿地 ,江心洲及江滩湿地和库塘湿地等 ,其中湖泊湿地面积最大 ,约 2 1 3.6km2 。该湿地计有水生及湿生维管植物 1 0 1种 ,分属37科 67属。文中分析了湿地维管植物的生活型、生态习性、群丛特征及价值 ,提出了湿地资源保护和利用措施。  相似文献   

7.
王青锋  王玉国  潘明清   《广西植物》2000,20(1):27-31
莽山自然保护区位于湖南省宜章县境内 (2 4°52′0 0″~ 2 5°0 3′12″N,112°4 3′19″~ 113°0 0′10″E) ,属南岭支脉。作者对该地区水生维管束植物及其生境进行了考察 ,采集到水生沼生维管束植物30科 4 7属 6 7种 ,其中 30种为莽山地区新记录。在比较沼泽和湖泊水生植物群落结构特点的基础上 ,讨论了沼泽作为水生植物重要生境的意义 ,建议对作为珍稀濒危水生植物重要产地的长江以南山地沼泽采取有效的保护措施  相似文献   

8.
鄂东花马湖水生高等植物研究:Ⅰ.水生植物区系   总被引:3,自引:1,他引:2       下载免费PDF全文
花马湖位于北纬30°15′—30°18′、东经114°58′—115°1′,面积约27.5km~2。湖中分布82种2变种水生维管束植物,隶属于34科66属,其中资源植物众多。花马湖水生高等植物大型属少,小型属较多,单型属相对突出。区系地理成分以温带成分占优势,计34种,占全湖种类的40.48%。起源古老的成分也较多。通过与有关湖泊水生植物区系的比较,及区系成分的分析,说明花马湖水生植物区系具有从暖温带至中亚热带过渡的特点。  相似文献   

9.
青岛市地处山东半岛西南端 ,位于北纬 3 5°3 5′~3 7°0 9′、东经 1 1 9°3 1′~ 1 2 1°。由于濒临黄海 ,受海洋季风的影响 ,雨量充沛 ,温度适中 ,冬无严寒 ,夏无酷暑 ,年平均气温 1 2 2℃ ,最低月均温 -1 2℃ ,最高月均温 2 5℃ ,植物资源丰富 ,昆虫及海洋生物多 ,是东部沿海候鸟迁徙的主要停歇地。青岛鸟类保护环志站是中国大陆最早建立开展鸟类环志研究的站点之一。迄今已环志鸟类 5 8万只。在 1 3处环志点开展了鸟类迁徙环志研究 ,积累了一些资料。目前已查明境内有旅鸟 2 52种、冬候鸟 3 4种、夏候鸟 4 9种。1 环志点及工作方…  相似文献   

10.
西双版纳位于云南南部边缘,地理位置为北纬21°09′~22°36′、东经99°58′~101°50′之间。面积19690平方公里,该地地处热北缘,长期受热带季风控制,气候条件十分优越。植物资源极其丰富。在西双版纳海拔800米以下的地区,降雨量在1500毫米左右,年平均气温为20℃左右,相对湿度较大。植被分类划分为热带雨林和热带季雨林。多年生植物呈现出大都无冬季休眠  相似文献   

11.
New sulfur derivatives of phosphoramidite ligands were synthesized and the impact of the sulfur unit on the spectroscopic properties of their rhodium and iridium complexes was investigated. The new ligands Bn2NPSCH2CH2Sa(P-Sa) (Bn = benzyl, 4), Bn2NPSCHCHSa(CH2)3CaH2(P-Sa)(Ca-Sa) (6) and Bn2NP(4-XC6H4OMe)2 (X = S, 7a; X = O, 7b) were converted to the rhodium and iridium complexes trans-[Rh(CO)Cl(L)2] (L = 4, 6, 7), [RhCl(COD)(L)] (L = 4, 6, 7), [IrCl(COD)(7a)] and [IrCl2Cp∗(6)]. For comparison, some phosphoramidite complexes of these formulations also were synthesized. The new metal complexes were spectroscopically analyzed. For the carbonyl complexes, the νCO IR stretching frequencies were lower than for the corresponding phosphite and phosphoramidite ligands. The 1JPRh coupling constants for the rhodium complexes with the new ligands were also smaller than for the respective phosphoramidite and phosphite complexes. Finally, the 1JPSe coupling constants of the selenides of the new ligands were lower than those of the phosphoramidite ligands but higher than for PPh3. The spectroscopic data reveal that the new thio ligands 4, 6 and 7a are more electron donating than phosphites and phosphoramidites but less electron donating than PPh3.  相似文献   

12.
《环境昆虫学报》2014,(5):790-804
综述了白蚁螱客的主要种类、共生关系及相关机制的研究进展。白蚁螱客中,已报道的动物种类达170种。在与动物的共生关系中存在偏利共生(宾主共栖和异种共栖)、互利共生和无关共生三种;在与微生物的共生关系中,存在与内生菌(原生动物、细菌、真菌和放线菌)和外生菌(蚁巢伞菌等)间的互利关系。指出了白蚁与螱客研究中存在的问题,给出了解决方案,并提出了今后可能的研究热点或方向,为白蚁的综合利用(如纤维素酶)及今后研究物种间的协同进化提供了基础资料。  相似文献   

13.
Astrocytes transport the monocarboxylate acetate, but synaptosomes do not. The reason for this is unknown, because both preparations express monocarboxylate transporters (MCT). The transport and metabolism of lactate, another monocarboxylate, was examined in these two preparations, and the results were compared to those for acetate. Lactate transport is more rapid in astrocytes than in synaptosomes, but of lower affinity (Kms of 17 and 4 mM, respectively). Lactate (0.2 mM) is metabolized to CO2 more rapidly in synaptosomes than in astrocytes (rates of 0.37 and 0.07 nmol x mg protein(-1) x min(-1), respectively). The reason for this is unclear, but cellular differences in lactate dehydrogenase isotype expression may be involved. Acetate is metabolized to CO2 more rapidly in astrocytes than in synaptosomes (rates of 0.43 and 0.02 nmol x mg protein(-1) x min(-1), respectively). This is likely due to cellular differences in the expression of monocarboxylate transporter subtypes.  相似文献   

14.
15.
The first and second sessions of the Workshop focussed on the basics of ultrasound and infrasound, their applications in both industry and medicine, and metrology and protection standards for ultrasound applications.  相似文献   

16.
To elucidate accumulation of minerals in human iliac arteries with aging, the content of minerals was analyzed by inductively coupled plasma atomic emission spectrometry. Bilateral common, internal, and external iliac arteries of 16 men and 8 women, ranging ages from 65 to 93 yr, were examined. It was found that an extremely high accumulation of calcium and phosphorus occurred in the common iliac artery at old age, being higher than that of the internal and external iliac arteries. It should be noted that the accumulation of calcium and phosphorus is the highest in the common iliac artery among the human arteries examined to date. Regarding sexual differences, the content of calcium and phosphorus in the common and internal iliac arteries was higher in women than in men, whereas their content in the external iliac artery was lower in women than in men.  相似文献   

17.
In spite of the many studies on protein modifications by reactive species, knowledge about the products resulting from the oxidation of protein-aromatic residues, including protein-derived radicals and their stable products, remains limited. Here, we compared the oxidative modifications promoted by peroxynitrite and myeloperoxidase/hydrogen peroxide/nitrite in two model proteins, ribonuclease (6Tyr) and lysozyme (3Tyr/6Trp). The formation of protein-derived radicals and products was higher at pH 5.4 and 7.4 for myeloperoxidase and peroxynitrite, respectively. The main product was 3-nitro-Tyr for both proteins and oxidants. Lysozyme rendered similar yields of nitro-Trp, particularly when oxidized by peroxynitrite. Hydroxylated and dimerized products of Trp and Tyr were also produced, but in lower yields. Localization of the main modified residues indicates that peroxynitrite decomposes to radicals within the proteins behaving less specifically than myeloperoxidase. Nitrogen dioxide is emphasized as an important protein modifier.  相似文献   

18.
19.
The ability of partially purified human and guinea-pig haematogenous cell populations, when cultured in vitro, to metabolise arachidonic acid (AA) has been studied. Supernatants from 24 hour cell culture have been subjected to analysis for products of AA metabolism by gas chromatography with electron-capture detection.The cell types studied were human peripheral blood monocytes (both glass adherent and non-adherent), neutrophils, eosinophils and leukemic leucocytes; thoracic duct lymphocytes and lung alveolar macrophages. From the guinea-pig, induced and non-induced macrophage or neutrophil enriched peritoneal exudate populations, lymph node cells, peritoneal eosinophils and peripheral blood platelets were examined. Supernatants were assayed for the presence of PGE2, PGD2, PGF, TXB2 and 6-keto-PGF. In all types studied PGE2 and TXB2 were the major products formed. The identification of PGE2 and TXB2 was confirmed by GC/MS with multiple ion monitoring.The results have been compared with other reports and their possible significance discussed in relation to the proposed role of prostaglandins as mediators and modulators in immunopathology.  相似文献   

20.
A new series of antibacterial and antifungal triazine-derived mono- and di-substituted (symmetrical and unsymmetrical) Schiff-bases and their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by their elemental analyses, molar conductances, magnetic moments and IR and electronic spectral measurements. IR spectra indicated the ligands to act as tridentate towards divalent metal ions via a trazine-N, the azomethine-N and, indole-NH and deprotonated-O of salicylaldehyde. The magnetic moments and electronic spectral data suggest octahedral geometry for the Co(II), Ni(II) and Zn(II)complexes and square-pyramid for Cu(II) complexes. NMR spectral data of the ligands and their diamagnetic zinc(II) complexes well-define their proposed structures/geometries. Elemental analyses data of the ligands and metal complexes agree with their proposed structures/geometries. The synthesized ligands, along with their metal complexes were screened for their antibacterial activity against Escherichia coli, Bacillus subtillis, Shigella flexneri, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. The results of these studies show the metal complexes to be more antibacterial/antifungal against two or more species as compared to the uncomplexed Schiff-base ligands.  相似文献   

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