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1.
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  
郝朝运  刘鹏  吕思田 《广西植物》2004,24(6):497-502
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   

2.
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   

3.
4.
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   

5.
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   

6.
Proposed new realignments in the angiosperms   总被引:1,自引:0,他引:1  
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   

7.
Linear rank test statistics are applied to the problem of estimating a treatment effect if two sets of censored failure time data are compared and the distributions of the log-failure times of the two samples are assumed to differ only in location. Rank tests for this accelerated failure time model are reviewed and Hodges-Lehmann type estimates for the shift parameter are proposed. Properties of these estimates are investigated, computational aspects are discussed and an example is presented.  相似文献   

8.
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   

9.
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   

10.
本文记述了我国双翅目食蚜蝇科缩颜蚜蝇族6属23种,其中有5新种2新纪录属13新纪录种,列出了属、种检索表,并对新种进行了形态描述,同时,对此族的地理分布、区系及起源进行了初步探讨。  相似文献   

11.
芜湖发电厂灰渣场植被状况   总被引:3,自引:3,他引:0  
王友保  张莉  刘登义 《应用生态学报》2002,13(12):1671-1673
经实地考察发现,芜湖火力发电厂灰渣场自然定居的高等植物有30种,隶属于14个科29个属,主要包括菊科,禾本科和豆科,全部植物中,1,2年生草本植物18种,多年生草本植物9种,木本植物2种,影响植物分布的主要因素是灰渣的理化性质和灰渣场的自然改造程度。  相似文献   

12.
离体草鱼肠道对亮氨酸和酪氨酸的吸收与利用   总被引:2,自引:2,他引:0  
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。    相似文献   

13.
G. B. CORBET 《Mammal Review》1988,18(3):117-172
All species and higher taxa of Recent Erinaceidae are diagnosed, the character-states most useful in classification are tabulated and the most probable phylogenies presented. Four African species are included in the genus Atelerix. The desert-adapted Paraechinus is believed to be more closely related to Atelerix than to the convergent Hemiechinus. The ranges of all species are mapped, with emphasis upon areas of parapatry and sympatry. Marginal localities are listed if they are not derived from previously published maps. All nominal fossil species that have been allocated to Recent genera are listed. Ecological data relevant to the interpretations of species boundaries, e.g. relating to diet and habitat, are summarized, and the factors likely to determine the species boundaries are reviewed.  相似文献   

14.
15.
The morphology of the gills, with their blood supply have been described in Notopterus notopterus and Colisa fasciatus in some detail. Gills are curved and perforated on the dorsolateral and ventrolateral wall of the pharynx. The gills consist of 2 rows of filaments which are stacked one above the other to form a space. The gill filaments are smaller on both the ends and larger in middle. The gill filaments are of pink colour as they are supplied with blood. Gill rakers are large in size in Notopterus notopterus while they are small in Colisa fasciatus. 3 pairs of basibranchials are present in Notopterus notopterus which are covered by median membranous bony plate while 2 basibranchials are present in Colisa fasciatus. 3 pairs of hypobranchials are present in both fishes. 5 pairs of ceratobranchials are present in which Vth ceratobranchial bears teeth. 4 pairs of epibranchials are present. 3 pairs of pharyngobranchials are present in which the tip of the IVth pharyngobranchial bears minute teeth in Notopterus notopterus while in Colisa fasciatus IInd and IIIrd pharyngobranchial bear minute ones. One afferent branchial vessel is present in Notopterus notopterus and Colisa fasciatus in each gill like in other teleostean fishes. One efferent branchial vessel is present in each gill of Notopterus notopterus while in Colisa fasciatus 2 efferent are represented in each gill.  相似文献   

16.
何若天   《广西植物》1985,(4):381-388
对马尾松幼苗子叶和胚轴、甘蔗、小麦、烟草、黄花菜等幼叶及其原生质体的过氧化物酶同工酶(POI)分别作比较研究。观察到凡经纤维素酶处理的各植物组织POI酶带数均多于未经纤维素酶处理的组织的酶带数;除个别例外,后者一般又比无壁原生质体的酶带数多。此种差异随植株生长年龄而增大,表明植物组织内大部分POI主要存于质外体中。  相似文献   

17.
Two-dimensional dynamic modelling of human knee joint   总被引:1,自引:0,他引:1  
A mathematical dynamic model of the two-dimensional representation of the knee joint is presented. The profiles of the joint surfaces are determined from X-ray films and they are represented by polynomials. The joint ligaments are modelled as nonlinear elastic springs of realistic stiffness properties. Nonlinear equations of motion coupled with nonlinear constraint conditions are solved numerically. Time derivatives are approximated by Newmark difference formulae and the resulting nonlinear algebraic equations are solved employing the Newton-Raphson iteration scheme. Several dynamic loads are applied to the center of mass of the tibia and the ensuing motion is investigated. Numerical results on ligament forces, contact point locations between femur and tibia, and the orientation of tibia relative to femur are presented. The results are shown to be consistent with the anatomy of the knee joint.  相似文献   

18.
辽宁革螨的生态地理分布   总被引:1,自引:0,他引:1  
李维贤 《昆虫学报》1991,34(1):108-116
辽宁省已知的革螨46种,分属于5科19属.本文依据四个不同地理景观区内革螨的优势种、常见种和罕见种,对其生态地理分布作了讨论.(1)辽西低山丘陵及沿海平原区:本区共有革螨20种,其中仓鼠真厉螨、格氏血厉螨为优势种;塔山巨刺螨、长毛鞘厉螨为罕见种.(2)辽东山地及半岛丘陵区:本区共有革螨22种.半岛丘陵革螨优势种为仓鼠真厉螨、格氏血厉螨;辽东山地革螨优势种为耶氏厉螨与东方真厉螨.本区罕见种为赛氏血革螨、达呼尔血革螨、大连肪刺螨、三角血厉螨等.(3)辽河平原区:本区共有革螨20种.优势种为耶氏厉螨与厩真厉螨;乌苏里土厉螨为罕见种.(4)努鲁儿虎山脉北麓黄土丘陵台地及西辽河沙地区:本区共有革螨26种.优势种为东北血革螨、仓鼠真厉螨及格氏血厉螨.巨腹赫刺螨、鼬赫刺螨、拟小赫刺螨、半漠血厉螨、乌苏地厉螨、北野血革螨、楠本血革螨等为罕见种.  相似文献   

19.
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   

20.
新疆蝗总科区系研究   总被引:8,自引:0,他引:8  
新疆现有蝗虫157种,它们分别隶属于8科62属。在157种蝗虫中,古北种占绝对优势,有120种,其次为特有种,有35种,广布种甚少,仅2种。在古北种中,中亚种最多,其次为泛古北种,而欧洲西伯利亚种、地中海种和东北种均很少。在8个科中,泛古北种在网翅蝗科中占优势,中亚种在班翅蝗科中占优势,斑腿蝗科在蝗总科中是相当大的一个科,在我国也占有很大优势,但在新疆其属种数量却很少。  相似文献   

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