【作者】 马福军；

【导师】 闫德飞；

【作者基本信息】 兰州大学 ， 古生物学与地层学， 2012， 硕士

【摘要】 在内蒙古自治区东乌珠穆沁旗的乌尼特煤田下白垩统巴彦花组下部含煤段保存有良好的植物化石分散角质层。将富含分散角质层的岩石样品自下而上分为6小层,并对各层内角质层进行分析。利用沈光隆等(1993)分散角质层的分类体系,划分出共计18种分散角质层类型,它们归属2大类,7类,12亚类。并以所研究的分散角质层材料为例,对沈光隆等(1993)的分类体系中的无气孔大类进行了补充,以表皮细胞形态特征为区分依据,建立了6个新的亚类。在此基础上,根据分散角质层微观构造,对各类型分散角质层的母体植物进行推测。结果表明：本文所讨论的分散角质层可能来自银杏纲的银杏属、拜拉属和茨康诺司基叶属,苏铁纲的侧羽叶属与似查米亚属,松柏纲的杉科。利用推断的分散角质层母体植物组合的总体特征,得知该区总体气候条件应属于温暖而潮湿的暖温带气候并具有季节性变化的特征。通过母体植物在各小层分布的差异性的研究,可以发现当时的古环境可能由温带向亚热带过渡的变化。最后,运用植物表皮气孔参数与大气CO2浓度呈负相关性关系,通过对岩石样品各小层分布较广泛的分散角质层具气孔大类六列气孔器类直壁亚类中的类型三的气孔参数进行统计,发现其气孔指数明显上升,可以推测在当时古C02浓度出现逐渐降低的变化趋势。更多还原

【Abstract】 This thesis deals with some dispersed cuticles, which were found in the Lower Cretaceous Bayanhua Formation of Wunite Coal Field in Inner Mongolia. The rock sample, which is rich in well-preserved dispersed cuticles, was divided into6successional layers. A total of18distinct forms dispersed cuticles,6without stomata and12with stomata, were recognized from the6layers. They are referable to12Subturma,7Turma,2Anteturma, accoding to the scheme of classification and nomenclature of dispersed cuticles proposed by Shen et al.(1993). Based on the shapes of the epidermal cells, the6forms without stomata can be described as6new Subturma, making some supplement for the Anteturma Estomatiferae in the classifying system of Shen et al.(1993). Ginkgo, Baiera, Czekanowskia, Zamites, Pterophyllum can be deduced as the parent plants of the corresponding dispersed cuticles according to the characteristics of the epidermal cells which have been known in fossil leaves. Basing on the assembling characteristics of the deducd parent plants, the climate in the sedimentary period of the Bayanhua Formation was probably a warm temperate with seasonal changes. The differences of the relative abundances of the deduced parent plants in each layer of the rock sample reveal that environment might change from temperate to subtropics at that time. As known, the negative relationships between atmospheric CO2concentration and leaf stomatal index (SI) have been proved. It shows that the changing trend of the atmospheric CO2was decreasing accompanying with the uplift of stomatal index of the Turma Hexastomatae Subturma Rectiseptae Type Three in the early Cretaceous Bayanhua Formation.更多还原