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1.
黑龙江鹤北地区维管束植物的区系分析   总被引:4,自引:0,他引:4  
张捷  胡秉坤  杨逢建  徐辉 《植物研究》2001,21(3):360-364
鹤北地区共有维管植物110 科, 412 属, 978 种, 其中蕨类植物有14 科18 属41 种, 裸子植物只有1 科4 属6 种, 被子植物有95 科390 属931 种。其植物区系成分特征为:(1)植物种类繁多;(2)区系成分丰富;(3)单属科和单种属较多;(4)存在许多孑遗种;(5)区系主要是北温带性质, 具有"南北混合型"特征。  相似文献   

2.
采用扫描电镜方法对中国藁本属20种及山芎属1种植物的果实表面微形态进行首次研究,并对其中15种进行果实解剖特征观察。结果表明:藁本属植物果实微形态在外果皮表面突起度、细胞轮廓、表面纹饰和表皮分泌物上表现出丰富的多样性;在果实解剖特征上,果棱形状、油管数目、胚乳形状等种间差异明显且稳定,而种内居群间无变异,可作为藁本属种间鉴定及种间关系探讨的重要参考性状。结合前人对伞形科其他类群果实微形态与解剖结构特征的研究及近年来分子系统学的证据,得出如下结论:(1)藁本属不是一个自然类群;(2)支持拟藁本属归入藁本属;(3)对藁本属部分种的系统位置和种间亲缘关系进行了讨论。  相似文献   

3.
中国飘拂草属植物果皮微形态   总被引:1,自引:0,他引:1  
利用扫描电子显微镜对国产莎草科飘拂草属4组18系42种1变种植物果皮微形态特征进行观察,并作了系统描述。研究表明,飘拂草属植物在纹饰类型,超微结构等方面存在着明显的种间差异,具有分类学意义。根据纹饰及微形态特征的不同,支持将褐鳞飘拂草和知风飘拂草各自作为独立的种。依照果皮纹饰的差异,飘拂草属可分为4种类型(1)瘤(疣)-网状复合纹饰;(2)瘤(疣)状纹饰;(3)网状纹饰;(4)脊-疣状复合纹饰。其中(1)和(3)类型的纹饰根据网脊曲直不同各自又可分为2个亚型。  相似文献   

4.
利用扫描电镜研究了中国萹蓄属(Polygonum) 13种、1变种、1变型植物的花粉形态.结果表明,中国萹蓄属植物的花粉粒为长球形或超长球形,具三孔沟,外壁纹饰可分为4种类型(1)花粉粒表面具细网状纹饰;(2)花粉粒表面具颗粒纹饰;(3)花粉粒表面仅两端具颗粒纹饰,其余部分光滑;(4)花粉粒表面仅沟间区两端肩部光滑,其余部分具颗粒纹饰.根据花粉形态类型,结合该属植物的习性、叶柄基部及花柄上关节的有无、花柱和柱头的数目以及瘦果形态等特征,参照前人的研究处理意见,将中国萹蓄属植物划分为4个组,即小灌木组section Fruticulosae (Boiss.) F.Z.Li et Y.T.Hou,stat.& comb.nov.、萹蓄组section Polygonum、丝茎萹蓄组section Pseudomollia Boiss.和铁马鞭组section Plebeia Tzvel..  相似文献   

5.
千佛山自然保护区种子植物区系特征研究   总被引:5,自引:0,他引:5  
在对千佛山自然保护区详细调查的基础上,对其种子植物的科、属分布区类型进行了统计分析。结果表明:(1)保护区内种子植物丰富,共153科767属2494种;(2)优势科、属明显;(3)区系起源古老;(4)种子植物地理成分复杂,吴征镒划分的中国种子植物属的15大分布类型在千佛山均有分布;(5)种子植物区系在科和属级水平上均显示出温带性质,温带分布属475属,占总属数的61.9%;(6)特有属、种丰富。  相似文献   

6.
资源冷杉是国家一级保护植物、中国特有种,呈极度濒危状态。采用样地调查法对江西南风面无人为干扰的原始森林资源冷杉所在群落特征进行研究,结果表明:调查群落共有维管植物68种,隶属34科47属; 含属种较多的科有杜鹃花科(2属8种)、山茶科(4属6种)、冬青科(1属6种)、樟科(2属5种)、壳斗科(3属4种),占总种数的42.0%; 热带性质的属共占非世界属总数的46.5%,温带性质的属共占48.8%,中国特有分布的属占4.7%; 古老的残遗属和亚热带山地的表征属占有极大的优势。群落乔木层可分为4层,第一亚层和第二亚层的优势种有资源冷杉、南方铁杉、南方红豆杉和多脉青冈等。调查的资源冷杉种群目前处于相对稳定的状态,所在群落是该地区的顶极群落。  相似文献   

7.
采用样方调查法,对中甸刺玫(Rosa praelucens)的群落特征进行分析。结果表明:(1)中甸刺玫群落中共有维管植物24科71属97种,其中,蕨类植物2科5属6种,裸子植物1科1属1种,被子植物21科65属90种;(2)群落垂直结构可分为乔木层、灌木层、草本层。乔木层及灌木层不发达,草本层较发达。根据Raunchier生活型谱划分,高位芽植物占优势(39.56%)。  相似文献   

8.
猕猴桃属9种植物的花粉形态研究   总被引:6,自引:0,他引:6  
本文利用扫描电镜和光学显微镜研究了猕猴桃属6种和3变种植物的花粉形态。本属花粉粒具三孔沟或三拟孔沟,外壁纹饰差异较大。可作为该属属下分组的重要依据之一。根据外壁纹饰,可将它们概括为4种类型:(1)皱块状表面具细条纹;(2)不规则的瘤状纹饰;(3)小沟状或小穿孔状;(4)较规则的瘤状纹饰类型。  相似文献   

9.
论中国软骨鱼类的地理分布和区系特征   总被引:2,自引:0,他引:2  
中国的软骨鱼类,就现时所知,共有127种、60属、28科,可归纳为如下14大类:(1)六鳃鲨类,有六鳃鲨1科3属3种;(2)虎鲨类,有虎鲨1科1属2种;(3)鼠鲨类,有锥齿鲨、鼠鲨、姥鲨、长尾鲨、须鲨和鲸鲨6科11属18种;(4)猫鲨类,有猫鲨、皱唇鲨、真鲨和双髻鲨4科19属43种;(5)角鲨类,只有角鲨1科2属4种;(6)锯鲨类,有锯鲨1科1属1种;(7)扁鲨类,有扁鲨1科1属2种;(8)锯鳐类,有锯鳐1科1属2种;(9)犁头鳐类,有犁头鳐和团扇鳐2科4属9种;(10)电鳐类,有电鳐和单鳍电鳐2科3属5种;(11)真鳐类,只真鳐1科1属7种;(12)魟类,有魟和燕魟2科5属17种;(13)鲼类,有鲼、鹞鲼、牛鼻鲼和蝠鲼4科6属12种;(14)银鲛类,只有银鲛1科2属2种。中国软骨鱼类的区系组成的特点以真鲨科、魟科和鲼科最为繁盛,其次是须鲨、猫鲨、长尾鲨和双髻鲨等科,但角鲨科、真鳐科和银鲛科的代表性则均较弱。中国软骨鱼类可分为暖水性种、暖温性种和冷温性种三种类型。暖水性种有74种,占中国软骨鱼类总数的59%;暖温性种有39种,占30%;冷温性种有14种,占11%。  相似文献   

10.
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   

11.
Comparative investigation of the inner surface of the needle cuticle of 36 species and 2 varieties of Abies under SEM has revealed that the characteristics of the intercellular flanges are rather distinct and four types can be distinguished: (1) Straight and developed single flange. This type is only represented by Abies bracteata D. Don. Morphologically, this species is also quite unique in the genus Abies and was once treated as a subgenus by Franco and Liu. Its special structure of the leaf cuticle observed here seems to support their treatment. (2) Double flanges. This type was first discovered in a leaf fossil of Abies from England. In modern plants of Abies, it is found only in the species from Central America. (3) Undeveloped single flange. This type is represented by a small group of Abies from the west and east coastal area of the Pacific Ocean. (4) Undulate and developed single flange. This type is represented by most of the species of Abies, including all the species in Europe and most species in Asia and North America. The flange types mentioned above seem to have some relationships with the geographical distribution of the species in the genus Abies, and their occurrence might have not been completely influenced by the habitats, hence the features of the intercellular flanges may provide good evidence for the subgeneric division of Abies. Based on our results and those from the previously published literature about the infrageneric treatments of Abies and the distribution of the fossils, we consider that western North America might be the diversity center of modern Abies. Florin once pointed out that the characters of the leaf cuticle in gymnosperms are of great significance for the generic andinfrageneric division. This viewpoint is strongly supported by our study on modern Abies.  相似文献   

12.
13.
Comparative investigation on the inner surfaces of needle cuticle of Pinus was made for 17 species and two varieties under SEM. It is shown that the differences in protrusions and depressions of the internal cuticle surfaces of needles in the genus are not remarkable. However, the features of intercellular flanges are rather distinct and three types can be distinguished. They are: (1) Subgen. Strobus (Sweet) Rehd (except Sect. Parrya) is of the Pinus koraiensis type; (2) Subgen. Pinus is of the P. tabulaeformis type; (3) Sect. Parrya Mayr of Subgen. Strobus (Sweet) Rehd is of the P. bungeana type. The character may provide taxonomy of the genus Pinus with a new piece of evidence. Based on the features mentioned above, together with many others, such as wood anatomy, warts of wood tracheids, bark structure, needle anatomy and cuticle structure as well as karyotypic analysis in Pinus, the author considers that division of Pinus into two subgeuera is natural and that separation of Sect. Parrya Mayr from Subgen. Strobus (Sweet) Rehd. and thesubsequent establishment of the subgenus Parrya of its own are also reasonable.  相似文献   

14.
松科冷杉属植物的化石历史和现代分布   总被引:2,自引:0,他引:2  
冷杉是北半球阴暗针叶林的优势种和建群种,现全世界共有52种1亚种12变种,在北半球形成南欧、北美和东亚三个分布中心,这三个地区也是冷杉属化石最丰富的地区。在垂直分布上,冷杉集中分布于1000~2000m(15种)和2500~4000m(13种)两个海拔地段。在中国,冷杉植物呈南北间断分布,集中分布在横断山地区。冷杉属的特有现象和孑遗分布现象都十分突出,有7个种呈孑遗分布。根据冷杉属的地史分布和现代分布的研究并结合最新的系统演化资料,本文推测冷杉属于白垩世中期起源于北半球的中高纬度地区,始新世以后,随着全球气候的变冷,逐步向南迁移,由于喜马拉雅山脉、阿尔卑斯山、落基山脉抬升及东亚季风气候的出现以及第四纪冰期的影响而形成了现代间断的分布格局。冷杉与银杉、金钱松等其它松科植物的形成模式十分相似。  相似文献   

15.
The plants of the genus Abies are dominant and key species in dark conifer forest in the Northern Hemisphere. There are 52 species, 1 subspecies and 12 varities of genus Abies in the world. The history and modern distribution ofAbies were discussed at present paper. The genus has 3 modern distributional centers: South Europe, North America and East Asia. These areas are also rich in fossil records. The vertical distribution regions of Abies are from sea level to 4 700m, concentrated in 1 000 - 2 000 m (15 species ) and 2 500 - 4 000 m ( 13 species ). In China, the genus distributes in 20 provinces, especially abundant in the Hengduan Mountians. Meanwhile endemic and relic phenomea are obvious in this genus. There are 7 relical species with both limited individuals and limited distributed regions. Based on the fossil records and the newest phylogenetic data, the following hypothesis was proposed: Abies originated from the mid- and high altitude of the Northern Hemisphere in the Middle Cretaceous and it was dispersed forward to the south area in the Eocene due to global climate cooler down. The distribution of Abies was deeply impacted by geological events such as upleft of Himalaya, Alps, Rocky Mountains, the occurrence of Aisan Monsoon as well as Quaternary glaciers. Finally the currentdistribution pattern appeared at the Quaternary. The genus Abies has similar fossil history and modern distribution pattern with Cathaya and Pseudolarix.  相似文献   

16.
椴树属的地理分布   总被引:13,自引:0,他引:13  
椴树属Tilia是椴树科一个形态特殊且唯一的北温带分布属,分布于亚洲、欧洲和北美,构成典型的北温带分布格局,三个分离的分布区之间缺乏共有种。本文对各分布区的种类进行重新评价,确认全属25种。其中东亚17种,占68%,包含了现存种类各个演化阶段的类群,是现代分布中心;欧洲-西西伯利亚6种,属于木果组及壳果组;北美2种,均为木果组成员。化石分布与现代地理分布格局基本相似,但分布纬度较现代分布偏北,达到北纬80°附近,且还出现于现今无椴树分布的亚洲大陆腹地,北美西部椴树至第三纪末完全绝迹,而东部到第四纪才有化石记录。根据现代地理分布,结合化石证据、地质历史、气候变迁及形态演化推测,椴树属可能在白垩纪晚期起源于中国东部亚热带山地,至少到始新世之前已散布至欧洲和北美西部。渐新世之后的全球降温和更新世大冰期对椴树属现代地理分布格局的形成起着至关重要的作用。  相似文献   

17.
杜鹃属植物的分类历来都十分重视叶片表皮特征的分类学价值,无论是在各亚属之间还是在种及种下等级的划分中都很强调此类特征的作用。贵州省位于世界现代杜鹃分布中心边缘及向东部散布的过渡地带,省内自然分布的杜鹃种类资源丰富而又独具特色,包括很多尚未深入研究的特有类群。为进一步研究贵州杜鹃属植物的属下系统分类关系,该文对自然分布于贵州的30种杜鹃进行了叶背显微形态特征研究,其中有28种的叶背表皮特征为首次报道。研究材料全部来自采于贵州西北部百里杜鹃自然保护区内的杜鹃属植物,包括杜鹃亚属4种、糙叶杜鹃亚属1种、常绿杜鹃亚属22种、马银花亚属1种及映山红亚属2种,共计30种。研究方法为取成熟叶片处理后在JSM-6490型扫描电镜下对叶背表皮进行观测。叶背鳞片类型的划分方法参照前人工作。结果表明:这30种杜鹃叶片叶背表皮形态特征在电子显微镜下表现出明显的多样性,如有鳞类杜鹃具有鳞片而其他类群则无,叶表面有或无表皮毛,表皮毛排列稀疏或密生,气孔器未见或偶见,散生于乳突状或非乳突状突起之间,或角质层增厚气孔器下陷,内、外拱盖表面粗糙或光滑,气孔器周围有或无间断的条形突起,突起呈环状或羽状等,但在同一亚属或亚组中又呈现出或多或少的一致性。研究讨论表明,叶背表皮显微形态特征在杜鹃属植物的属下系统分类中具有重要的研究价值。  相似文献   

18.
The extant woody family Altingiaceae, consisting of only one genus Liquidambar L. with ca. 15 species, demonstrates a typical disjunctive distribution among East Asia, North America, and the Mediterranean. However, the fossil record throughout the Cenozoic indicates that Altingiaceae was once widespread in the Northern Hemisphere. After studying the abundant Altingiaceae fossil leaf collections, we revised the easily-confused fossil leaves and corrected the misidentifications. Consequently, we proposed an evolutionary history of Altingiaceae leaf morphology in consulting the modern leaf characteristics. It is revealed that the trilobated leaf morphology is the ancestral character state, whereas both the pentalobated and the undivided, pinnate-veined lineages evolved separately. The latter diverged from the trilobated ancestor in South China in Eocene. The lobed and undivided lineages represent the deciduous and evergreen, respectively. An extensive fossil database of Altingiaceae was built to reconstruct its biogeographical history. We reconfirmed that Altingiaceae developed into a temperate and a subtropical-tropical patterns and migrated across both the Bering and North Atlantic land bridges since Cretaceous, independently. It was widespread in the early Neogene of North America and Eurasia, and became extinct in the high latitude triggered by the global cooling and aridification. The modern disjunctive distribution was finally formed, with southeast Asia as its modern diversity center. This study provides new fossil evidence for understanding the morphology and biogeography of the family Altingiaceae.  相似文献   

19.
? Premise of the Study: Calocedrus is among the genera with a typical eastern Asian-western North American disjunct distribution today. The origin of its modern distribution pattern can be better understood by examining its fossil record. ? Methods: The present article reports for the first time a new fossil species of this genus based on compressed material from the Oligocene Ningming Formation of Guangxi, South China, in its present major distribution area in eastern Asia. ? Key Results: Calocedrus huashanensis sp. nov. is most similar to the two extant eastern Asian species, C. macrolepis and C. formosana, in gross morphology of foliage shoots and bears a close resemblance to the latter in cuticle structure. It shows a general similarity to the North American fossil representatives of the genus in alternately branched foliage shoots but is clearly different from the European Paleogene species characterized by oppositely branched leafy shoots. ? Conclusions: This discovery provides new evidence for the floristic exchange of this genus between eastern Asia and North America before the Oligocene (most likely in the Eocene), presumably via the Bering land bridge. The flattened leafy shoots and dimorphic leaves with thin cuticle, open stomatal pits, and shallowly sunken guard cells of the present fossils suggest a rather humid climate during the Oligocene in the Ningming area, South China.  相似文献   

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