本文選題：中國西南地區(qū)　切入點：晚二疊世　出處：《云南大學》2015年碩士論文　論文類型：學位論文

【摘要】：蘆木是晚古生代種類繁盛的大型木賊類植物的總稱,是石炭二疊紀最常見的植物化石之一,也是重要的成煤植物。目前歐美植物區(qū)蘆木類植物的研究已經(jīng)比較深入和全面,但華夏植物區(qū)蘆木類植物,特別是蘆木莖解剖結(jié)構(gòu)的研究還很少。我國西南地區(qū)貴州盤縣礦區(qū)和云南富源地區(qū)晚二疊世地層中產(chǎn)有豐富的、保存完好的蘆木莖干化石,為深入了解晚二疊世蘆木類植物的形態(tài)結(jié)構(gòu)、系統(tǒng)發(fā)育與演化提供了重要的化石材料。本論文利用國際上研究礦化植物化石廣泛采用的揭膜法和薄片法,對產(chǎn)自云貴地區(qū)晚二疊世地層中的大量蘆木莖礦化化石進行了詳細的研究,主要結(jié)果如下： 根據(jù)大量新發(fā)現(xiàn)的標本對已報道的蘆木莖筠連節(jié)莖木Arthropitys junlianensis進行了深入研究,并對其種征進行了修訂,修訂后的種征為：植物體為高大喬木,直徑可達300mm；莖中央存在一個中空的髓腔,在髓腔邊緣具有溶解性空腔；初生射線極快速尖滅,很短,最長達2mm；脊管小而明顯,呈卵圓形；在脊管(carinal canal)附近的髓邊緣中具有成團分布的黑色分泌細胞；木質(zhì)部束頂端鈍尖,寬約700μm(500gm-1000μm)；2到3圈卵圓形細胞環(huán)繞脊管；次生木質(zhì)部發(fā)達,厚可達100mm,由梯紋管胞構(gòu)成；次生射線窄,由1到2列薄壁細胞組成。 描述了一個相似種Arthropitys cf. A. yunnanensis。該種特征為：莖直徑超過100mm;莖中央存在一個中空的髓腔,初生射線寬度具有明顯收縮,從近髓處開始向外快速變窄,貫穿次生木質(zhì)部時很細,并有部分沒有貫穿次生木質(zhì)部；脊管明顯,呈卵圓形；2到4圈卵圓形細胞環(huán)繞脊管；次生木質(zhì)部發(fā)達,每個木質(zhì)部束頂端呈尖錐型,寬約1000μm-1500μm,由梯紋管胞構(gòu)成；次生射線細胞在橫切面徑向長為寬的1-2倍,弦切面為等徑的薄壁細胞；具發(fā)育的皮層,皮層內(nèi)有一圈葉痕排列,皮層寬度約5mm,分3層。 通過對已發(fā)現(xiàn)的我國西南地區(qū)晚二疊世3種蘆木莖特征的研究,發(fā)現(xiàn)3種蘆木莖的次生木質(zhì)部均較發(fā)育,說明它們均是較高大的喬木狀植物或小樹,個體數(shù)量較豐富,可能在當時植被中占據(jù)優(yōu)勢地位；地理分布范圍較廣,至少在整個西南地區(qū)都有分布；生活環(huán)境多樣,除生活于岸邊或水中外,還有可能生活于高地甚至山坡上；部分標本具有明顯的生長輪,表明在該時期該地區(qū)氣候出現(xiàn)了周期性季節(jié)變化,但并不穩(wěn)定。
[Abstract]:Reed is a general term for the late Paleozoic species of large scale cuttlefish. It is one of the most common plant fossils of the Permian period, and is also an important coal-forming plant. At present, the research on the rosewood species in Europe and the United States has been comparatively thorough and comprehensive. However, there are few studies on the anatomical structure of Reed stem in Huaxia plant area, especially the anatomic structure of Reed stem. In the late Permian strata of Panxian mining area and Fuyuan area of Yunnan Province in southwest China, there are abundant and well-preserved rosewood stem fossils. In order to understand the morphology and structure of the late Permian plants, phylogeny and phylogeny provide important fossil materials. In this paper, the thin-film method and the thin-film method, which are widely used to study mineralized plant fossils, are used in this paper. A large number of mineralized fossils from late Permian strata in Yungui area were studied in detail. The main results are as follows:. According to a large number of newly discovered specimens, the reported Arthropitys junlianensis was studied, and its species sign was revised. The revised species sign was that the plant was tall and tall. The diameter can reach 300 mm, there is a hollow medullary cavity in the center of stem, which has a dissolved cavity at the margin of the medullary cavity, the primary ray is very fast, very short, and the longest is up to 2 mm, the spinal canal is small and obvious, and it is oval. There are black secretory cells in the medullary margin near the spinal canal; the xylem bundles are obtuse at the tip of the xylem bundles, with 2 to 3 circles of oval cells around the spinal canal about 700 渭 m ~ 500gm-1000 渭 m wide; the secondary xylem is well developed, up to 100 mm thick, and is composed of trapezoids; the secondary rays are narrow. Consists of 1 to 2 rows of parenchyma cells. A similar species, Arthropitys cf. A. yunnanensis, is described. The characteristics are: the diameter of the stem is more than 100mm; there is a hollow cavity in the center of the stem, the width of the primary ray is obviously contracted, and the width of the primary ray shrinks rapidly from the near pulp to the outside, and it is very thin when it penetrates through the secondary xylem. Some of them did not penetrate the secondary xylem, the spinal canal was obviously oval, with 2 to 4 circles of oval cells surrounding the spinal canal, the secondary xylem was well developed, each xylem bundle was acicular at the top of each xylem bundle, and its width was about 1000 渭 m to 1500 渭 m, which was made up of trapezoid tracheids. The radial length of the secondary ray cells is 1-2 times as wide as the transverse plane, and the chord section is an equal-diameter parenchyma with a developed cortex, with a ring of leaf marks arranged in the cortex, the width of the cortex is about 5 mm, and the cortex is divided into three layers. Based on the study of the characteristics of the three species of Reed stems in the late Permian in southwest China, it is found that the secondary xylem of the three species are relatively developed, indicating that they are tall Arbor plants or small trees, and the individuals are rich in number. It is possible to occupy a dominant position in the vegetation at that time; the geographical distribution is relatively wide, at least in the whole southwest region, the living environment is diverse, in addition to living on the shore or in the water, it is possible to live on the high ground or even on the hillside; Some of the specimens had obvious growth rings which indicated that the climate of the region had periodic seasonal changes but was not stable during that period.
【學位授予單位】：云南大學
【學位級別】：碩士
【學位授予年份】：2015
【分類號】：Q914

【參考文獻】

相關(guān)期刊論文 前1條

1 馮卓;ZIEROLD Thorid;R銉BLER Ronny;;巨大的二疊紀木賊[J];科學通報;2012年18期

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本文編號：1584438