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浙江磐安种子植物区系的特征分析 总被引:5,自引:0,他引:5
磐安约有野生种子植物 1 44科 ,62 7属 ,1 2 98种 (包括种以下分类单位 )。其中世界成分的属 67个 ,占总属数的 1 0 .69% ,热带属 2 2 7个 ,占 36.2 0 % ,温带属 32 1个 ,占 5 1 .2 0 % ,中国特有属 1 2个 ,占 1 .91 %。磐安气候温暖湿润 ,植物种类丰富 ,古老、孑遗、珍稀植物多 ,单种属和少种属占有较大比重 ;优势科、优势属明显 ,优势科 34个 ,共含有 393属 ,776种 ,分别占总属数总种属的 62 .7% ,70 .3% ,优势属 1 0个 ,共含有 1 44种 ,分别占总属数总种数的 1 .6% ,1 1 .1 % ,其中樟科、壳斗科等是该区系的表征科 ;植物分布类型多样 ,地理成分复杂 ,温带成分和热带成分占优势 ,是亚热带分布的北缘 ,与世界各地有广泛的联系 相似文献
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江西木兰科植物的初步整理 总被引:3,自引:1,他引:2
通过野外采集及标本的整理鉴定, 确认江西产木兰科植物7 属22 种1 亚种, 其中3 种为江西特有种, 5 种为江西地理新分布。对各分类群进行了分类检索, 记载了其地理分布, 并列出凭证标本。 相似文献
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ELECTRON MICROSCOPIC STUDIES OF MITOSIS IN AMEBAE : II. The Giant Ameba Pelomyxa carolinensis
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Dividing nuclei from the giant ameba Pelomyxa carolinensis were fixed in osmium tetroxide solutions buffered with veronal acetate to pH 8.0. If divalent cations (0.002 M calcium, magnesium, or strontium as chlorides) were added to the fixation solution, fibrils that are 14 mµ in diameter and have a dense cortex are observed in the spindle. If the divalent ions were omitted, oriented particles of smaller size are present and fibrils are not obvious. The stages of mitosis were observed and spindle components compared. Fibrils fixed in the presence of calcium ions are not so well defined in early metaphase as later, but otherwise have the same diameter in the late metaphase, anaphase, and early telophase. Fibrils are surrounded by clouds of fine material except in early telophase, when they are formed into tight bundles lying in the cytoplasm unattached to nuclei. Metaphase and anaphase fibrils fixed without calcium ions are less well defined and are not observably different from each other. The observations are consistent with the concept that spindle fibrils are composed of polymerized, oriented protein molecules that are in equilibrium with and bathed in non-oriented molecules of the same protein. Partially formed spindle fibrils and ribosome-like particles were observed in the mixoplasm when the nuclear envelope had only small discontinuities. Remnants of the envelope are visible throughout division and are probably incorporated into the new envelope in the telophase. Ribosome-like particles are numerous in the metaphase and anaphase spindle but are not seen in the telophase nucleus, once the envelope is reestablished, or in the interphase nucleus. 相似文献
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广东深圳塘朗山郊野公园共有野生维管植物144科423属611种,分别占广东省维管植物280科1589属5737种的51.4%、26.7%和10.65%;其中蕨类省植物21科29属33种,裸子植物3科3属4种,被子植物120科391属574种,被子植物占绝对优势。国家重点保护野生植物共计7科7属7种,占广东省国家重点保护野生植物的10.9%;珍稀濒危植物有4科5属5种,占广东省珍稀濒危植物67种的7%。公园中经济植物可分为12类,分别是药用植物321种,用材树种65种,观赏植物60种,纤维植物41种,野生水果33种,油脂植物38种,饲料植物42种,鞣料植物42种,野菜植物25种,农药植物27种,芳香植物26种,淀粉植物23种,保健植物19种,染料植物13种,有毒植物10种,蜜源植物5种。 相似文献
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广西金钟山鸟类保护区鸟类多样性初步研究 总被引:7,自引:0,他引:7
本文共记录到金钟山鸟类274种,分别隶属于18目57科,其中陆生鸟类251种,水鸟23种;以留鸟为主,共157种;候鸟、旅鸟分别为104种、13种;东洋种为优势类群,共有171种,古北种和广布种分别为4种、27种。这些鸟类中有国家重点保护鸟类39种,中国特有种鸟类3种,列入世界自然保护联盟红皮书名录中的鸟类5种,列入中国濒危动物红皮书名录中的鸟类20种,列入CITES附录中的鸟类34种。本文还对金钟山鸟类保护区的5种不同生境类型的鸟类种类组成作了比较,结果表明灌丛+农田的鸟种多样性指数最高,为3.04;水域的鸟种多样性指数最低,为2.14。 相似文献
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Proposed new realignments in the angiosperms 总被引:1,自引:0,他引:1
Robert F. Thome 《Nordic Journal of Botany》1983,3(1):85-117
Our attempt at putatively phylogenetic classifications of Angiospermae, considering our vast ignorance of more than 120 million years of evolution of the class, must be very tentative and elastic to make full use of the new approaches and new data constantly being made available to us. Some of the realignments thus required in my system of classification are here explained. Among others, the Paeoniales are recognized and include Glaucidiaceae; various shifts of families are made within Thei–florae–Violiflorae–Malviflorae; Thymelaeaceae and Simmondsiaceae are transferred to Euphorbiales; Emblingiaceae, Gyrostemonaceae and Bataceae are added to Sapindineae; Fabineae, with Connaraceae, Surianaceae and Fabaceae, are transferred to Rutiflorae; Proteiflorae are placed near Rutiflorae, especially Fabineae; the largely Australasian–African Pittosporales are explained; Cornaceae are severely pruned; Haemodoraceae and Velloziaceae are transferred to Commelinales; Arecales, Cyclanthales and Pandanales are separated into unrelated superorders; and Typhiflorae are moved into closer proximity with Commeliniflorae. 相似文献
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ANDERS WAREN 《Zoologica scripta》1980,9(1-4):187-210
All species that have been described of the genera mentioned in the title are listed and their systematic position given. The species of Stilifer (with 11 species, including S. inflatus sp.n. and 5. concavus sp.n.) are parasites of starfishes. Scalenostoma (3 species) are parasites of stone corals. Thyca (with 8 species) is removed from Capulidae, and included in Eulimidae. T. hawaiiensis sp.n. is described. The species of Thyca are parasites of starfishes. The species of Mucronalia (including M. trilineata sp.n.) are probably parasites of ophiuroids and Echineulima (with 4–6 species, including E. ponderi sp.n.) are parasites of echinoids. All species are figured, their characteristics are given and their host species and distributions are listed. Keys are given to the species of each genus, except Mucronalia. The genera Stilimella Laseron and Hyperlia Pilsbry are synonymized with Scalenostoma and the genera Kiramodulus Kuroda, Granulithyca Habe and Bessomia Berry are considered subgenera of Thyca. 相似文献
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采用同位素示踪和肠道离体灌流方法,研究了草鱼离体肠道对亮氨酸(Leu)、酪氨酸(Tyr)的吸收转运与利用。实验结果表明:当Leu浓度从1.0mmol/L增加到5.0mmol/L、10mmol/L时,肠道吸收转运的速度表现出“高浓度抑制”效应,运输到肠道外的比例为83%、66%和35%;合成肠道蛋白质的比例为2%、5%和13%;肠道组织内游离形式的比例为9%、28%和49%;其他形式的比例为6%、1%和3%。Tyr浓度从0.5mmol/L增加到1.5mmol/L、2.5mmol/L时,肠道对Tyr的吸收转运速度也随之增加,运输到肠道外的比例为52%、55%和55%;合成肠道蛋白质的比例为17%、15%和16%:肠道组织内游离形式的比例为7%、10%和16%;其他形式的比例为24%、20%和13%。肠道在吸收转运Leu和Tyr的同时,也利用它们合成蛋白质的和其他方面,Leu的吸收利用受灌流试验氨基酸浓度影响较大、而Tyr受影响较小;随着肠道内灌流的试验氨基酸浓度增加,吸收转运到肠道外的比例下降、留存于肠道内的比例增加,肠道合成的蛋白质绝对量也增加。
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桂西北典型喀斯特区生态服务价值的环境响应及其空间尺度特征 总被引:6,自引:0,他引:6
Study on ecosystem service values (ESVs) is the bridge of understanding ecosystem and economic decision-making. To investigate the response of ESVs to ambient environment and their spatial scales is an urgent work in the process of ecological restoration and sustainable development in southwest China. Based on the previous research results, the remote images, and weather data of 31 years (1975-2005), the response of ESVs to ambient environment and their spatial scales in a typical karst area of northwest Guangxi, China were evaluated with the method of empirical mode decomposition (EMD) in this paper. The results showed that ESVs had obvious variations with changes in elevation, rocky types and soil types, and had corresponding characteristics of spatial scales. The ESVs in middle and low elevation areas were higher, but they decreased due to human activities such as deforestation. The ESVs in peak-cluster depression areas were lower, and they would increase as influenced by policies such as returning farmland to forestland. The ESVs were influenced by rocky types, showing lower values but an increasing trend in the typical karst regions while higher values but a decreasing trend in non-karst regions. The average ESVs in the west part of the study region, which is not only the main nature reserve for rare wildlife species in Guangxi, but also one of the best preserved natural vegetation regions in China, were more than 15,000 RMB Yuan ha-1,. Comparatively, the ESVs were less than 10,000 Yuan ha-1 in the middle part of the region attributed to low vegetation coverage, serious peak-cluster depression and karst rocky desertification. After about 20 years, that is from 1985 to 2005, the ecosystem conditions had been improved and the ESVs had increased in the middle and eastern part of this study region. On the contrary, in most western part, which was dominated by subtropical evergreen broad-leaved forest, they had been worsened, and the balance values of ESVs were negative. As for the relationships of ESVs with rocky types and soil types, lime soil and red soil were the two main soil types that contributed to ESVs (The total contribution was above 60%, and it is 63.77%,64.37%,64.56%,64.91% respectively in the four years of 1985, 1990, 2000 and 2005.). The variance contribution of intrinsic mode function (IMF) and trend (R) showed that there were obvious special sales for ESVs in this study area, and the main spatial scales were about 2.7 km, 5.5 km, and 11.6 km. The variance contribution ratio was 12.29%, 11.26%, 11.49% respectively, and the trend (R) was high (17.74%). In conclusion, this study indicated that ecosystem conditions in the typical karst area were improved owing to the application of rocky desertification control policies, such as ecological migration and returning farmland to forestland. Besides, the main spatial scales of ESVs in the study area were the interactions of terrain, physiognomy, land use / land cover and human activities. 相似文献
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峨眉山蕨类植物区系的初步研究 总被引:1,自引:1,他引:0
依据2004~2006年的野外调查和标本馆标本以及文献资料,初步分析了峨眉山蕨类植物区系的地理特征,结果表明:峨眉山共有蕨类植物46科110属425种,优势科为蹄盖蕨科、水龙骨科和鳞毛蕨科,共192种,占总种数45.2%,优势属为耳蕨属、鳞毛蕨属、凤尾蕨属和蹄盖蕨属等;在科、属的水平上,为热带分布型,以泛热带分布为主,而种的地理分布则以温带分布的中国特有和东亚成分占绝对优势,分别为36.5%和32.0%,揭示了峨眉山蕨类植物区系是以温带性质为主的亚热带类型,具有较强的热带亲缘;与大巴山关系密切,和云南哀牢山有一定的联系,而与秦岭、西藏和陕西天华山的关系较为疏远。 相似文献
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经调查粤东地区有中国珍稀濒危保护植物 2 7种 (含栽培种 ) ,分属于 2 4科 2 6属 ,占广东境内分布的中国珍稀濒危保护植物的 4 5 .8% ,占全国分布的 6 .9%。其中蕨类植物 1种 ,裸子植物 6种 ,被子植物 2 0种 ;确定为濒危植物的有 5种 ,稀有的 4种 ,渐危的 18种 ;被列为一级重点保护的 1种 ,二级重点保护的 7种 ,三级重点保护的 19种。有国家重点保护野生植物2 2种 (含栽培种 ) ,分属于 2 0科 2 0属 ,占全国重点保护野生植物的 8.3%。其中蕨类植物 5种 ,裸子植物 6种 ,被子植物 11种 ;被列为一级重点保护的 6种 ,二级重点保护的 16种。其国家保护植物资源具有种类丰富、古老性强、中国特有现象突出等特点。对其名录特点和利用价值也进行了分析 相似文献
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沙冬青冬季叶绿体的超微结构特征 总被引:2,自引:0,他引:2
韩善华 《分子细胞生物学报》1994,(4)
沙冬青在冬季的叶肉细胞中有丰富的叶绿体,经常聚集在一起,相互重叠,相互嵌合,有的还相互融合。大部分叶绿体为凸透镜形,多余叶绿体主要为V形、蝶形、连婴形和哑铃形。它们的被膜不光滑,常凹凸不平,甚至出现突起和内陷。类囊体十分发达,质体小球很多,但淀粉粒缺乏。大部分叶绿体形态结构正常,有的还在出芽和分裂。少数叶绿体与此不同,它们已经衰老,其中一些正在解体或已经解体。 相似文献
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中国东北地区木材腐朽菌的多样性(英文) 总被引:4,自引:7,他引:4
对中国东北地区木材腐朽菌资源研究进行了总结,给出了每种木材腐朽菌的寄主和在东北的分布。目前中国东北地区共记载木材腐朽菌504种,其中300种为多孔菌,204种为革菌,57种为林木病原菌,69种为药用菌。梨多年卧孔菌Perenniporia pyricola和北方赖特孔菌Wrightoporia borealis为新种,对它们进行了描述和绘图。对所有名称按最新命名法规(维也纳法规)进行了订正。 相似文献
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中国罗汉松属叶角质层微形态结构及其分类意义 总被引:1,自引:0,他引:1
利用扫描电镜对罗汉松属8种2变种植物叶角质层内外表面进行了细致观察。发现罗汉松属植物叶角质层结构具有许多相似特征,表皮细胞较为规则,长方形或多边形,边缘波状弯曲;气孔器排列成带状,长轴均与叶脉一致,气孔器具较为明显的气孔塞和伏罗林环,气孔器保卫细胞极延伸明显,通常具有2~4个副卫细胞、不具极副卫细胞。但罗汉松属叶角质层结构也具有明显的种间差异,镰叶罗汉松和洛杉矶罗汉松同其它种类差异最大,这两种植物叶两面均具气孔器,角质层内表面垂周壁直,角质层凸缘不明显;贺氏罗汉松最为显著的特征是近轴面和远轴面表皮细胞的垂周壁角质层厚且凸缘均极其发达;小叶罗汉松近轴面表皮细胞排列较为规则,多数为方形,长轴与叶脉垂直,垂周壁之间的角质层突起较为显著,延伸到皮下层;兰屿罗汉松近轴面表皮细胞排列较不规则,多边形,细胞的角端比较钝,没有棱角;大理罗汉松气孔带间隔较小,有时两条气孔带挤在一起,使副卫细胞紧连,近轴面表皮细胞较短,方形或长方形,垂周壁之间的角质层较不发达;海南罗汉松角质层气孔带间隔较宽,气孔器形状为阔椭圆形,近轴面表皮细胞均为细长方形;变种短叶罗汉松和狭叶罗汉松与罗汉松也具有明显差异,短叶罗汉松近轴面表皮细胞排列不规则,垂周壁深波状弯曲,凸缘极为明显,但原种罗汉松近轴面表皮细胞排列较为规则,垂周壁浅波状弯曲,凸缘不明显,而狭叶罗汉松近轴面表皮细胞方形或长方形,比罗汉松的表皮细胞短,垂周壁直或略弯曲,角质层极厚。这些角质层微形态特征差异可以作为罗汉松属内种类分类鉴定的依据。 相似文献