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1.
河南固始早石炭世杨山组植物群   总被引:2,自引:0,他引:2  
系统描述了扬山组植物18属25种,其中以石松类及种子蕨和真蕨纲为主,仅少数属楔叶纲;石松类中发现不少叶座较小,叶痕相对较大的鳞木类植物,颇似华夏植物群中的鳞木类;首次报道了我国发现的古芦木孢囊穗.据对植物群综合分析,杨山组的时代为早石炭世中晚期.  相似文献   

2.
河南固始早石炭世杨山组植物群   总被引:6,自引:0,他引:6  
吴秀元 《古生物学报》1992,31(5):564-584
系统描述了扬山组植物18属25种,其中以石松类及种子蕨和真蕨纲为主,仅少数属楔叶纲;石松类中发现不少叶座较小,叶痕相对较大的鳞木类植物,颇似华夏植物群中的鳞木类;首次报道了我国发现的古芦木孢囊穗.据对植物群综合分析,杨山组的时代为早石炭世中晚期.  相似文献   

3.
对甘肃华亭延安组植物化石进行了宏观形态和表皮构造分析,经鉴定共有24属49种。该植物群组成为:真蕨纲(28.6%)、银杏纲(38.8%)繁盛,松柏纲(16.3%)、楔叶纲(8.2%)和苏铁纲(4.1%)占一定比例,石松纲和种子蕨纲未见。与国内、外侏罗纪植物群或组合,特别是与我国北方中侏罗世11个研究较为系统的植物群进行了详细的对比和分析。结果表明,当前植物群明显具有中国北方Coniopteris-Phoenicopsis植物群早期组合的特点,其地质时代归为中侏罗世早期,大致相当于阿林期(Aalenian)至巴柔期(Bajocian)。华亭延安组化石植物以温暖湿润气候下繁盛的植物类型为主,兼具少数亚热带、热带气候下的植物成分,说明甘肃华亭地区中侏罗世为偏湿润的暖温带气候。  相似文献   

4.
为明确河北省石家庄市菜用大豆田节肢动物群落结构特点及其多样性,应用马来氏网,对该地区菜用大豆田的节肢动物进行采集及种类鉴定,并对其群落结构组成、主要类群发生动态进行研究。结果表明:石家庄市菜用大豆田中共诱集到各类节肢动物3纲11目94科255种6927头,其中唇足纲45头,弹尾纲31头,昆虫纲6851头。在昆虫纲中,数量从大到小顺序为:半翅目>双翅目>鞘翅目>缨翅目>鳞翅目>膜翅目>脉翅目>直翅目>蜻蜓目。主要类群包括叶蝉科、蚜科、蓟马科、夜蛾科、薪甲科、瓢甲科、蚜蝇科。叶蝉、蚜虫、蓟马、夜蛾和叶甲为优势害虫种群。蚜蝇、瓢虫为主要天敌。该地区菜用大豆田的节肢动物种类和个体数量均远多于其他地区大豆地块。多样性分析表明,石家庄市菜用大豆田的节肢动物群落结构多样性指数、均匀度指数和丰富度指数均较高,说明该地区节肢动物群落具有较高稳定性。  相似文献   

5.
本文对甘肃宝积山盆地中侏罗世植物群地质时代及植物区系进行了探讨,共统计植物大化石18属53种,主要包括银杏纲10属24种,真蕨纲5属22种,苏铁纲1属3种,松柏纲1属2种,楔叶纲1属2种。该植物群在组成特征上表现为银杏类、真蕨类植物繁盛,其他植物类群相对贫乏。基于该植物群特征与国内其他植物群的对比,提出其地质时代为中侏罗世Aalenian期–Bajocian期。通过哈曼、欧式距离、罗杰斯–塔尼莫特和索卡尔–施尼斯4种方法对宝积山盆地及中国北方其余11个中侏罗世植物群进行系统聚类分析,在此基础上进一步划分了中国北方植物区系。通过计算属、种相似性系数,探讨宝积山邻近植物区系间的亲缘关系,结果表明宝积山植物区系与同属西北地区的华亭植物区系关系较为亲近。  相似文献   

6.
刺镰蕨在早泥盆世是一种广布于世界的植物,尽管报道自许多地点,但远未完全地了解它,其主要原因是能育材料罕见。我们观察的标本采自贵州早泥盆世的丹林组。它显示具柄的孢子囊侧生于靠近叶腋的轴上,我们的标本近似球形的孢子囊和它的形态略小于雷诺的肾形孢子囊外,其它方面如:带状的营养轴上具有疏螺旋排列的镰刀状叶,具短柄的孢子囊侧生于轴上以及管胞具穿孔壁等性状与雷诺修订后的刺镰蕨完全一致。我们同意雷诺的观点,将镰蕨目升为纲,与工蕨纲和石松纲并列。它的系统位置是介于工蕨纲和石松纲之间。其下包含一目、一科三个属——镰蕨属、巴拉格瓦纳彻属和星木属。这种植物的生殖部分在中国尚属首次报道。  相似文献   

7.
本文对甘肃宝积山盆地中侏罗世植物群地质时代及植物区系进行了探讨, 共统计植物大化石 18 属 53 种, 主要包括银杏纲 10 属 24 种, 真蕨纲 5 属 22 种, 苏铁纲 1 属 3 种, 松柏纲 1 属 2 种, 楔叶纲 1 属 2 种。该植物群在组成特征上表现为银杏类、真蕨类植物繁盛, 其他植物类群相对贫乏。基于该植物群特征与国内其他植物群的对比, 提出其地质时代为中侏罗世 Aalenian 期–Bajocian 期。通过哈曼、欧式距离、罗杰斯–塔尼莫特和索卡尔–施尼斯 4 种方法对宝积山盆地及中国北方其余 11 个中侏罗世植物群进行系统聚类分析, 在此基础上进一步划分了中国北方植物区系。通过计算属、种相似性系数,探讨宝积山邻近植物区系间的亲缘关系, 结果表明宝积山植物区系与同属西北地区的华亭植物区系关系较为亲近。  相似文献   

8.
河南东南部早石炭世植物群   总被引:4,自引:0,他引:4  
研究了河南东南部商城和固始杨山组植物化石,共计11 属18 种。它们分属于石松纲、楔叶纲、真蕨纲、种子蕨纲、科达纲和裸子植物种子,其中以石松纲鳞木类植物占优势。杨山组植物群含有一些典型的早石炭世分子, 如 Archaeocalam ites scrobiculatus、Cardiopteridium spetsbergense、Rhodeopteridiumhsianghsiangense,它们在维宪期至纳缪尔早期地层是颇为常见的;然而这一植物群也含有某些华夏型的鳞木类植物,即Lepidodendron cf.aolungpylukense、L.shanyangense、L.cf.subrhom bicum 等。根据植物群的总体组成,杨山组植物群的地质时代属于早石炭世晚期,大致相当于维宪晚期至纳缪尔A期。当前植物群可以与甘肃东部、陕西山阳、华南和马来西亚西部等的一些同期植物群进行对比,对比结果表明与陕西山阳植物群最接近。此外,笔者还讨论了全球早石炭世晚期植物群的分布  相似文献   

9.
"前华夏植物群"一词由李星学等提出,原义指以西北地区下石炭统(臭牛沟组、靖远组为主)及华南相当地层中的植物总称。作者分析了当前古植物地理区划的有关理论,结合中国的具体情况,提出"前华夏植物群"的涵义不但可以代替欧美植物群中拟鳞木植物群(Lepidodendropsis flora),而且还可能包括自早志留世植物登陆以来至早石炭世,在中国大陆(或称华夏复合大陆)生长的、独立的植物群。文中以晚泥盆世—早石炭世的植物群中独特的科、属、种等地方性土著分子为例,以当前古植物地理区的有关理论为依据,认为"前华夏植物群区"可以从以往的"欧美植物群"或"拟鳞木植物群"区中单独划分出来成为独立的植物地理区。  相似文献   

10.
内蒙草原不同植物功能群及物种对土壤微生物组成的影响   总被引:1,自引:0,他引:1  
为了分析不同植物群落组成对内蒙古典型草原土壤微生物群落组成的影响,本研究利用植物功能群剔除处理实验平台,采用荧光定量PCR(real-timePCR)和自动核糖体间隔区基因分析(automated ribosomal intergenic spacer analysis,ARISA)技术,对不同植物功能群组成的非根际土壤和常见物种的根际土壤中细菌和真菌的数量及群落结构进行了分析。结果表明,在非根际土壤中,不同植物功能群组成对细菌数量有显著影响,而对真菌数量及细菌和真菌的群落结构影响不明显;在根际土壤中,不同植物物种对细菌、真菌的数量都有显著影响。此外,聚类分析表明,不同物种的根际土中细菌和真菌的群落结构也有所不同,尤其以细菌的群落结构变化较为明显。研究结果表明不同植物物种可以通过根系影响土壤微生物群落组成。  相似文献   

11.
Noeggerathiales are a little known group of Carboniferous and Permian plants of uncertain systematic position that have been variously considered to be ferns, sphenopsids, progymnosperms, or a separate group. These heterosporous plants carry adaxial sporangia on leaf-like or disk-shaped sporophylls that form cones. Leaves are pinnate with a rather stiff appearance, and pinnules can be attached in either two or four rows. In the present report, we present the top of a noeggerathialean plant with leaves and strobili attached, Paratingia wudensis Wang, Pfefferkorn et Bek sp. nov., from an earliest Permian volcanic ash fall tuff in Inner Mongolia. The excellent preservation allows the reconstruction of the whole plant, the complex three-dimensional leaves with anisophyllous pinnules, the heterosporous strobili, and the spores in situ. The homology of leaves and strobili can be elucidated and contributes to an understanding of the debated taxonomic position of Noeggerathiales. The "anisophyllous" leaves carry pinnules arranged in four rows. The strobili are bisporangiate and have disk-shaped sporophylls, each with one ring of 10-14 adaxial sporangia around the strobilus axis. Megaspores have an equatorial bulge. This new species expands the known diversity of Noeggerathiales. It grew in a peat-forming forest, thus changing earlier interpretations of the growth of noeggerathialean plants with anisophyllous pinnules.  相似文献   

12.
Several isolated marattialean synangia and sporangia are reported from coal balls collected from Coal Seam No.1 (C605) in the uppermost Permian Wangjiazhai Formation in Guizhou Province, south-western China. The synangia are radially symmetrical with diameters between 0.8 and 1.2 mm and are 1.7 mm long, consisting of 3–4 elongate sporangia that are fused basally, free distally and possess a pointed apex. The outer-facing sporangial wall is 4–5 cells thick and conspicuously differentiated. Spores are trilete, have a granular ornamentation and are nearly round equatorially with a diameter of 55–60 µm. Comparisons with other anatomically preserved Palaeozoic marattialean synangia from the Euramerican and Cathaysian floras permit their assignment to the genus of Scolecopteris (Zenker) Millay. In this species the thick, outer-facing sporangial walls and large trilete spores are features consistent with those of the Oliveri Group within Scolecopteris , a group that has previously been considered primitive within this genus. Distinctions from all other previously recognized species within the Oliveri Group lead to the creation of a new species, S. guizhouensis sp. nov. This species is the youngest of the reported species of Scolecopteris recognized from the Euramerican and Cathaysian floras, and provides important evidence on the organization of marattialean ferns from the Upper Permian strata of south China.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 279–288.  相似文献   

13.
海南和台湾蕨类植物多样性及其大陆性特征   总被引:10,自引:1,他引:10  
海南和台湾是我国南部和东部两个最重要的大陆性岛屿,具有极为丰富的蕨类植物多样性。特有现象揭示着植物区系和植物多样性的历史,间断分布揭示着与邻近或相关植物区系的联系;特别是在岛屿地区,这种现象和意义尤其明显。海南有蕨类植物区系55科、135属、466种,其中特有种有32种,台湾蕨类植物区系57科、142属、599种,其中特有种达66种。在海南与台湾两地,有共有属104属,共有种仅有176种。台湾海峡出现始于晚白垩世,持续至第四纪;琼州海峡出现于早第四纪,因此,两地的特有现象远少于种子植物(台湾有801种,海南有501种),原因与蕨类植物具有更广的散布性相关,而且在被子植物中起重要作用的物种生物学障碍(机制)在蕨类是缺乏的;形态学的、生殖生物学特征导致蕨类植物具有较缓慢的物种演化历史和较低的灭绝率(Smith,1972)。海南和台湾蕨类植物区系的比较还表明,地理位置和海拔高度对植物区系的物种分化和物种多样性产生了极大的影响。  相似文献   

14.
Many genera and species of present-day aecial rusts on seed plants are derived directly or indirectly from a limited group of these pathogens on northern conifers, whereas conifer rusts are believed to have descended from their progenitors on ferns. It is worth noting that only the Pinaceae, Taxodiaceae and Cupressaceae serve as alternate hosts to an extensive rust flora on ferns and angiosperms which are distributed predominantly in the northern hemisphere. Numerous conifers in the southern hemisphere do not bear rusts, except a few endemic species on Araucariaceae in Malaysia and south central Chile.Such a disjunctive distribution of conifers and their specialized rusts is attributed now to extensive continental drift. Evidence indicates that the breakup of the primary land mass Pangaea into northern Laurasia and southern Gondwanaland, with successive splitting and drifting of these supercontinents, has also scattered ancient land faunas and floras.Plant Science Research Division, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Maryland. Plant Introduction Investigation Paper No. 29.  相似文献   

15.
王杰青  关崇  祝宁 《植物研究》2006,26(4):508-512
对城市绿地土壤种子库的组成、种群数量、空间分布和物种多样性进行了初步研究,结果表明:城市绿地土壤种子库存中共出现植物42种,其中在第一层中共出现植物1 477株,多样性指数为2.05,均匀度是0.58,最大的物种多样性指数是3.56,第二层的物种多样性指数,均匀度和最大物种多样性指数均比第一层要低,分别为1.94、0.56和3.47,植物种类也要少一些。城市绿地土壤种子库中种的丰富度、种子苗量、多样性指数均不如远郊区山地天然次生林。城市绿地土壤种子库中蕴藏着一些潜在种群,有些植物种可以用于城市绿化建设。  相似文献   

16.
报道了产于中国二叠纪煤核中的 3种具解剖构造的鳞木类叶 ,它们都具双木质部束 ,与似封印叶属 (Sigil lariopsisScott)特征一致。与该属已有种进行了对比 ,确认它们为 3个新种 :产于山西太原西山煤田太原组上部 7号煤层 (早二叠世早期 )煤核中的山西似封印叶 (Sigillariopsisshanxiensissp .nov .)和太原似封印叶 (S .taiyuanensissp .nov .)以及产于贵州水城矿区汪家寨组 1号煤层 (晚二叠世晚期 )煤核中的贵州似封印叶 (Sigillariopsisguizhouensissp .nov .)。根据煤核中共生的鳞木类植物其他器官以及欧美植物区鳞木类植物的研究资料推断 ,它们可能属于封印木属 (SigillariaBrongniart)的叶。在国外 (主要是欧美植物区 ) ,封印木属植物主要分布于石炭纪 ,见于二叠纪的封印木很少。华夏植物区的封印木属过去很少发现 ,其叶和生殖器官均未报道过。本文是首次报道华夏植物区具解剖构造的封印木属的叶 ,它们的发现不仅丰富了华夏植物区封印木属植物的内容 ,而且对于研究封印木属的演化以及华夏植物区与欧美植物区鳞木类植物之间的关系也具有重要的意义。  相似文献   

17.
A distinctive kind of anatomically preserved cardiocarpalean ovule is described from the Early Permian Taiyuan Formation of northern China. Ovules are small, have 180° rotational symmetry, and possess variably thick integuments with prominent secretory cavities that may be empty, filled with resinous materials and in several instances appear to contain animal coprolites. Comparisons show that (where known) these features conform to those of Callospermarion undulatum (Neely) Rothwell, to which they are assigned, previously only known from the Pennsylvanian of Euramerica. These fossils represent the first indisputable occurrence of the genus Callospermarion in the Early Permian Cathaysian floras, and show the presence of callistophytalean seed-ferns in this palaeofloristic realm for the first time. These data combined with results from previous investigations now support the Early Permian northern Cathaysian flora including the Taiyuan Formation having evolved from the Late Carboniferous and earliest Permian Euramerican flora, with which it shares far too many generic level similarities for these co-occurrences to be coincidental. Our hypothesis is therefore that the Early Permian flora of the northern Cathaysian realm represents the continued evolution of wetland Euramerican-type coal-swamp floras, and as such is likely to present a model for evolutionarily driven floral change as opposed to the climatically driven floral changes observed in the Euramerican flora after the demise of coal-swamp environments. The distribution of coprolites in and immediately around glandular cavities in this species suggests specialised syndromes of herbivory existed in Early Permian Cathaysian ecosystems, with herbivores preferentially selecting these areas of the ovule integument.  相似文献   

18.
报道了产于中国二叠纪煤核中的3种具解剖构造的鳞木类叶,它们都具双木质部束,与似封印叶属(Sigillariopsis Scott)特征一致.与该属已有种进行了对比,确认它们为3个新种:产于山西太原西山煤田太原组上部7号煤层(早二叠世早期)煤核中的山西似封印叶(Sigillariopsis shanxiensis sp. nov.)和太原似封印叶(S. taiyuanensis sp.nov.)以及产于贵州水城矿区汪家寨组1号煤层(晚二叠世晚期)煤核中的贵州似封印叶(Sigillariopsis guizhouensis sp.nov.).根据煤核中共生的鳞木类植物其他器官以及欧美植物区鳞木类植物的研究资料推断,它们可能属于封印木属(Sigillaria Brongniart)的叶.在国外(主要是欧美植物区),封印木属植物主要分布于石炭纪,见于二叠纪的封印木很少.华夏植物区的封印木属过去很少发现,其叶和生殖器官均未报道过.本文是首次报道华夏植物区具解剖构造的封印木属的叶,它们的发现不仅丰富了华夏植物区封印木属植物的内容,而且对于研究封印木属的演化以及华夏植物区与欧美植物区鳞木类植物之间的关系也具有重要的意义.  相似文献   

19.
The current level of understanding of the morphological variability of Pennsylvanian lyginopterid seed ferns is reviewed. This group of pteridosperms that ranges throughout the Carboniferous is represented by a heterogeneous assemblage of stems, leaves, ovules and pollen organs. Vegetative organs have been useful in tracing the origin of the eustele from a protostele, while the fern-like fronds appear to have had their origin from a non-planated branching system. The small radially symmetrical ovules, while exhibiting some diversity in the organization of integument, demonstrate little apparent alteration in pollen-receiving mechanisms and reproductive versatility. Lyginopterid pollen organs are synangiate and include both radial and bilateral forms. The stratigraphically earliest types are radial and borne upright on naked branches, while later forms are usually bilateral and typically associated with laminar foliage. Pollen is morphologically and structurally similar to the spores of many ferns, and probably germinated through the proximal suture. The apparent homogenous nature of lyginopterid seed ferns may indicate that relatively little evolution had taken place over a long geological time span. However, evidence from some compression floras suggests that far more diversity exists within the order in a non-swamp environment than had previously been thought. Current concepts about lyginopterid pteridosperms that have been developed from a small group of plants in a relatively homogeneous environment may need considerable revision as we learn more about the non-swamp inhabiting forms.  相似文献   

20.
A new species of the isoetalean leaf genus Lepidophylloides is described. This Guadalupian species from the Paraná Basin, Lepidophylloides corumbataensis, found as silicified microphylls in the Corumbataí Formation in the municipality of Piracicaba, São Paulo state, in southern Brazil, is the first species of the genus to be formally described for Brazil, and possibly the first for Gondwanaland. This is also the first time that surviving palisade tissue has been found in a species of Lepidophylloides. The new species is compared to known species and shown to be distinct from all previously described from Euramerican and Cathaysian floras. The organization of the xylem in arch-like or crescent-shaped bundles suggests a relation to Cathaysian species. The close association with Lycopodiopsis derbyi stems (which have true leaf scars and must have suffered leaf abscission) suggests that they are different organs from the same species.  相似文献   

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